한국철도학회:학술대회논문집 (Proceedings of the KSR Conference) (Proceedings of the KSR Conference)
한국철도학회 (The Korean Society for Railway)
- 반년간
과학기술표준분류
- 기계 > 자동차/철도차량
- 건설/교통 > 철도교통기술
한국철도학회 2007년도 추계학술대회 논문집
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An electric motor unit (EMU) is manufactured from a large number of components and parts which are made of extensive raw materials. In emits much environmental load throughout its entire life cycle, having both complicated and elaborated system and long period of life time. Therefore, it is necessary to investigate the methodologies and tools to analyze the environmental performance of EMUs throughout their life cycle. RACE (Rail Assessment for Clean Environment) developed in this study is the software that can analyze the environmental impacts and eco-efficiency of EMUs, which are new concepts proposed for sustainable development. It has database for main components as well as principal materials contained in EMUs. Manufacturers and operators can use it to assess the life-cycle environmental impacts of EMU and support their decision making. RACE can also be used as a tool for environmental communication between manufacturers and operators.
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The objective of this research is to comparative LCA(life cycle assessment) between two different model of Electric Motor Unit(EMU).the environmental impact of Aluminum body Electric Motor Unit(EMU) and Stainless Steel(STS) body Electric Motor Unit(EMU). LCA process consists of four steps which are goal, scope definition, life cycle impact analysis(LCIA) and life cycle interpretation. ISO 14044 provides the LCA standard method which can be conducted by using comparative LCA. From the research it is foung that the Aluminium Body Electric Motor Unit (EMU) is 3.6ton heaver than Stainless Steel(STS) body Electric Motor Unit(EMU). The system boundary of both Electric Motor Unit (EMU) are same life span and travel same distance. These both Electric Motor Unit (EMU) has same kind of environmental impact which is maximum Ozone Depletion(OD). During using period of these two models, the Aluminium Body Electric Motor Unit(EMU) has more global warming(GW) effect but Stainless Steel(STS) body Electric Motor Unit(EMU) has more Ozone Depletion(OD) effect. The above result is obtained by using LCA software PASS verson 3.1.3.
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Ecodesign is specific process integrating environmental aspect as a cost, quality, function into the stage of product development. Ecodesign is one of importance elements for sustainable development, a lot of company and institute have been tried to integrate environmental aspect into the stage of product development. But there's almost no endeavor to improve environmental aspects of electrical moto unit in korea. In this research, LCA was conducted for identifying environmental key issue of EMU. Also EQFD was conducted for analysis of stakeholder requirements. Combining each results from LCA and EQFD by using environmental strategy. Advancing to measure, task from environmental strategy. Finally, EMU was redesigned and we took ecology profile of redesigned EMU including eco-efficiency.
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In recent, a great number of electric motor units (EMUs) have been disused in Korea according as its legal duration is 25 years. Generally, the disused EMUs are disposed by selling original form or scrapping for junk. Until now, any efficient disposal system for disused EMUs has not existed. The purpose of this study was to develop the recycling process for the FRP used as an interior panel of EMU. This process was to manufacture a product mixing binders, fillers and the powdered FRP. The characteristics of a product were changed with the mixing ratio of the powdered FRP. The optimal ratio of the powdered FRP was from 10 % to 15 % (w/w). In the future, the application of this process can enhance the efficiency of resource recycling and decrease the cost of waste treatment in the EMU industry.
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Industry faces a considerable challenge to meet the high demand for reduced impacts and improved environmental performance. With this current stream, railway industry launched a systematic scheme for environmental friendly EMU and its system. An assessment tool which evaluate the environmental impacts of the product through its entire life cycle has been developed. The next step to environmentally sound and sustainable product design, shortly ECODESIGN has come to be essential and necessary as well. Ecodesign requires to identify possible stakeholder requirements first. The paper illustrates way how to define stakeholder requirements in terms of environment and shows approach linking stakeholder requirements to environmental parameters.
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In Korean Electric Motor Unit(EMU) industry, the government should lead and drive the development of the product-oriented fundamental technologies(for example, Life Cycle Assessment, Environmental Labelling, Ecodesign, Eco-efficiency etc.) for the EMU. International Railway Union(UIC) establish UIC code 345: Environmental specification and it is based on using the product-oriented fundamental technologies. And also many foreign railway related companies already shown their environmental performance using the product-oriented fundamental technologies So, in Korean situation, it is important that let the EMU industrial player understand the importance of the product-oriented fundamental technology for the EMU and clarify who drive the development of the product-oriented fundamental technology for the EMU and what the type of driving forces.
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Structural integrity of railway vehicles should last for a long period against various and continuous fatigue loadings, and the carbody structures of railway vehicle are manufactured by applying multiform welding types for each material. Since the most of cracks are occurred and proceeded at the vicinity of welding area during the lifetime of carbody structure, the fatigue strength evaluation for welding area of carbody structure should have been carried out. Rotem Company has evaluated lifetime and fatigue strength of carbody structure according to the fatigue analysis based on the international standard and/or inner-official regulation. This study introduces the fatigue analysis method that we have evaluated and calculated the damages for the welding areas of carbody structure under various fatigue loading conditions using cumulative fatigue damage rule(Miner's rule) to verify whether the cumulative damage does exceed unity. This study contains the fatigue test of specimens to derive stress-life relations(S-N curve), sub-modeling analysis and the calculation of cumulative damages under fatigue loading. The fatigue analysis verifies the welding area shall be capable of withstanding under fatigue loading, identifies how critical area shall be selected and presents the principles to be used for design verification.
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A contact patch between the wheel and the rail supports the train body and a traction power comes from it when rolling stocks run on the railroad. Friction force between the wheel and rail makes the train move on the rail. Whenever the train runs on the rail, the wheels and rails wear down by frictions inevitably. So it must be shaped by the lathe or changed for the safety train operation and the comfortable ride. Until now, many measures were carried out in order to prevent a wear and tear of the wheels. For example loop line railway in Kun Ja depot and Ji Chuk depot. This document reports the wheel changing data taken by maintenances department for the period before and after 1996 in the 1.2.3.4 lines in Seoul metro.
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Pantograph of the electric train is the important part receiving current by adhereing contact wire. Wearing rate of pantograph or contact wire is changed by the type of pantograph and material of adhering part. In special, the weather influences the relative wearing rate and wearing type of pantograph Slider and Contact wire with steep wearing in arc and life cycle of pantograph slider. Presently, the weather causes side-wearing and over-wearing of pantograph slide installed in electric train. So it is difficult to manage and operate the electric train. Although the quality of slide using in line4 vehicle was finished the test in line 2 vehicle experimentally, it has to apply after pantograph is installed in some electric trains and check the influence in it and contact wire. It is because line4 section is very different from line2 section. Experimental application is the sequence to certify the safety and abrasion resistance importantly by enlarging experimental application with increase of the experimental electric train. The lenth of line4 in Seoul Metro is 71.5[km]. It is long section. The line is mixed DC 1,500[V] section and AC 25,000[V] section. It has underground section of 41.5[km] and ground section of 30[km]. Ground section is about 42% and receives much influence in the rain during the rainy season. After experimental application we found that this pantograph slide has twice as much abrasion resistance despite a little deviation and found the occurrence probability of arc and side-wearing is decreased considerably.
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RIMS(Rolling Stock Information Maintenance System) was installed in structure which it can analyze the data base in need of credibility maintenance. So it could accumulate real data without repulsion of working spot. Information system was installed not following to system but following to working spot. The development of RIMS project was started from March 29, 2001 and it has been operating from October 12, 2004 in Chang-dong Car depot for light maintenance in charge subway line4. So substantial data base was accumulated for three years. This study calculated all RAMS data by analyzing data base accumulated in RIMS and used in dada base about credibility maintenance and found investigation of propriety, expectation of the life cycle cost, the improvement plan on credibility of sorts of cars and formation about the cycle of repairing and maintenance. This got MKBSF MKBF and MTBF about devices and sorts of line4 Rolling Stocks for it.
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Welding is the most commonly used method to produce bogie and carbody of Electrical Multiple Units(EMU), because it increases the strength and lowers the weight of EMU. Since bogies are constantly exposed to repeated reacting load during acceleration and deceleration, it is also true that crack normally occurs at welding parts. In this study, we have investigated the fatigue strength of SS400 on welded parts in order to find efficiency of treatment after welding by shot peening and Post-Weld heat treatment(PWHT) with butt welded specimens. The results of fatigue test indicate that the measurement of base material specimen is 236MPa, welded specimen is 132MPa and the specimen of PWHT is 107MPa approximately. We concluded that the measurement of welded specimen and PWHT is approximately 44 and 54 percents lower than the base material specimen, respectively. Another finding is that the peened specimen is approximately 23 and 61 percents higher than the base material specimen in terms of the fatigue in strength of specimens.
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The surface of railway wheel tread in wheel-rail system can not be free from wear because of various circumstance such as railway condition, maintenance condition, weather condition, characteristics of wheel surface's geometrical shape, and vehicle suspension's structural characteristics etc. Therefore, the research on wear reduction and maintenance method are very important to ensure the safety of railway vehicle, to improve car comfort and to decrease maintenance cost. In this study, the wear rates of railway wheel have been periodically measured in terms of the running distance of Electrical Multiple Unit which have been currently operated and the microstructure transformation of wheel tread using replication method have been performed. The results show that the relations between the flange wear and tread microstructure are depended on running distance and it will supply basic data on wheel maintenance.
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본 연구에서는 국내 철도차량에 적용되는 제륜자에 대해 차륜마모, 제동성능, 차량성능 측면에서 조사되어지고 평가되어진다. 국내의 제륜자 특성 및 형상이 비교, 평가되어지며 국내 철도 차량에 적합한 특성 및 형상을 추천하고자 한다.
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Sound transmission characteristics are investigated on the corrugated steel and aluminium extruded panels used for railway vehicles. Sewell-Sharp-Cremer(SSC) model, equivalent orthotropic plate model and equivalent mass law are applied to predict the sound transmission loss. The predicted values of the sound transmission loss are compared with the measured values. The reliability and the limitation of the prediction models are investigated. For the corrugated panels and honeycomb panels, the coincidence and local resonance severely deteriorate the sound insulation performance around the corresponding frequency bands. The result of the study shows that the equivalent orthotropic plate model and the SSC model can be used as good prediction models, if the coincidence frequency or local resonance frequency is correctly applied.
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There are the high-speed train of two types in Korea, KTX and KHST(Korean High Speed Train). The characteristics of interior noise appear differently because the car bodies of the trains are designed with the different materials. In this study, we measure the interior noise for KTX and KHST. The experimental results show that the interior noise of KTX is equal to KHST in open territory and tunnel and interior noise in tunnel with concreted track increase about
$3{\sim}4dB(A)$ compared to tunnel with ballasted track. We also know that interior noise level of KHST is higher then KTX in range of high frequency (above 630Hz). -
The traction motor for High Speed Train is being required reliability and stability for high-speed operation. And also required low noise level, high performance, compact size owing to the space and weight limitation for attaching to train, etc. As a result of requiring the low noise level and high power capacity, it is adopted forced-air-ventilation insead of self-ventilation that is generally used on electric multiple unit. Traction motor is cooled by cooling air through the air-ventilation hole. When the traction motor is operated with forced-air-ventilation, there is some abnormal noise in the specific RPM. This paper is dealing with the method to reduce the resonance phenomena by adopting the rotor blade.
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Noise pollution from a high speed train has been a serious social issue nowadays. Especially when a train speed exceeds 300km/hr, an aerodynamic noise level has been known to be increased based on 4-6th power laws. In this paper, a simple approach to evaluate the sensitivity effect on noise due to the speed change has been examination.
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In this paper, the equations of motion by which the natural vibration of rotating thick ring can be analyzed accurately are presented. These equations are derived from the theory of finite deformation and the principle of virtual work. The effects of variation in curvature across the ring cross-section can be considered in these equations. The ring models are called as thick ring model and thin ring model respectively as the effects of variation in curvature are considered or neglected. The radial displacement of ring which is rotating at constant angular velocity is determined by a non-linear equation derived from the principle of virtual work. The equations of the in-plane and out-of-plane vibrations at disturbed state are also formulated from the principle of virtual work. They can be expressed as the combination of the radial displacement at the steady state and the disturbed displacements about the steady state. The natural vibrations of rings with different thickness are analyzed by using the presented ring models and 3-dimensional finite element method to verify accuracy of the presented equations of motion. Its results are compared and discussed.
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The noises which occurs from the rolling stock can be divided largely into three classes and they are Rolling noise, Traction noise and Aerodynamic noise. In the event of braking the rolling stock which enter into the station, Brake shoes cause Fraction noise (braking noise) and excessive braking noise makes passengers and operators uncomfortable. This study is to reduce squeal noise and minimize displeasure by measuring the braking noise and defining the major noise sources and noise mechanism
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To predict the fire and smoke hazards of rail car with a evacuation model is essential for achieving life safety of all passengers in the event of fire. Currently, more than 30 different evacuation models are available and expected increasing demand in high population density areas as a metro train station. This paper includes brief history of evacuation models and review some key factors of design egress scenario, these are pre-movement time, egress route, location of fire, overturned carriage, and configuration of rail car. Applying the egress model for rail passenger car, users need to confirm the model's ability of physiological, psychological responses effecting to pre-movement time of individual or crowd unit, representation of complexity of carriage layout, and evaluation of effects of smoke.
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When constructing a high-speed railroad, the reduction of the distance between track centers and the width of track bed may bring about the effect of cost savings. When, however, considering the influence that the increase of wind pressure due to the change of the distance between track centers may have on the stability of train operation, extensive technical review and overall studies need to be performed before the distance between track centers is determined. Therefore, in this study, the impact that the increase in wind pressure due to the change of aerodynamic phenomena with the change of the distance between track centers may have on two trains passing by each other was predicted, and the stability of train operation was analyzed in order to review the distance between track centers suitable to Honam HSR trains. In this study, we estimated the aerodynamical effects by the results of the real train experiments.
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The service running of driverless rail vehicle has been required by various social and commercial issue. Currently, the new domestic line between Bu-san and Gim-hae is plan to be provided the LRV(Light Rail Vehicle) with driverless operation firstly in domestic service. These driverless vehicle have some major properties to make it lower the operating and maintenance cost, however on the other side, it unavoidably raise some potential hazard to make it lower the passenger safety because it is hard to take care immediately in emergency state during vehicle running. Therefore it is highly requested that we should consider various conditions at design stage to manufacture and operate the safest vehicle. Therefore, in this paper, we will survey the design concept of vehicle interior facilities based on the previous experience, (1) The difference of interior facilities between normal and driverless vehicle, (2) design and operational concept of passenger side door function to find out best application for domestic line driverless vehicle.
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RIMS(Rolling Stock Information Maintenance System) was installed in structure which it can analyze the data base in need of credibility maintenance. So it could accumulate real data without repulsion of working spot. Information system was installed not following to system but following to working spot. The development of RIMS project was started from March 29, 2001 and it has been operating from October 12, 2004 in Chang-dong Car depot for light maintenance in charge subway line4. So substantial data base was accumulated for three years. This study calculated all RAMS data by analyzing data base accumulated in RIMS and used in dada base about credibility maintenance and found investigation of propriety, expectation of the life cycle cost, the improvement plan on credibility of sorts of cars and formation about the cycle of repairing and maintenance. This got MKBSF MKBF and MTBF about devices and sorts of line4 Rolling Stocks for it.
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It is important to manage internal and external interfaces in a system integration. As there are many of related multi-disciplinary engineers and high level complexity in big and complex project, it is difficult that carrying out interfaces management by consistent method. We study the method that represent efficiently system interfaces by matrix structure. And we suggest the way to identify system interfaces and trace interfaces between components using Interface Analysis Matrix and Interface Control Document.
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한국철도공사는 고속철도의 운행을 계기로 선진철도 정비방법의 습득과 더불어 기존차량에 대한 검수주기 및 방법에 대한 과학적이고 체계적인 시행을 위해 철도차량 RCM적용에 관한 연구를 시행 중이다. 그 동안 철도차량의 부품과 시스템에 대한 기술의 발전이 급속히 이루어지고 있는 것에 비해 정비방법의 발전은 상대적으로 느렸다고 할 수 있다. 이에 한국철도공사에서는 부품과 시스템의 기술발전에 앞서는 정비방법의 적용은 물론이고 차량의 기술적 발전을 리드할 수 있는 정비체계를 구축하고자 노력하고 있다. 고속차량인 KTX를 제외한 기존차량은 전동차, 전기기관차, 디젤기관차, 디젤동차, 객차, 화차 등으로 구분하여 운행되고 있다. 그 중 객차, 화차를 포함한 기존차종에 현행 시행되고 있는 검수 주기 및 방법을 분석하여 개선방향을 찾아 최적의 차량정비 주기 및 방법을 적용하고자 한다.
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For ensuing rolling stock safety, it is necessary that safety management should be made systematically through its whole life cycle. That is to say, safety management activities for every steps of rolling stock life cycle should be defined, and the roles of managers such as executor, assessor, and certificator should be shared clearly. This paper defines the safety management activities based on IEC 62278, analyzing foreign and domestic safety regulation systems, and suggests the reformed safety management system for rolling stock in Korea
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The purpose of Railroad Vehicles License Management in accordance with the Railroad Safety Law is to improve the quality of railroad safety. And the train simulators come into use for training of train operation and testing to issue Railroad Vehicles License. So, It is very important that the simulators for the Railroad Vehicles License Test require to work correctly, to measure driver's operation quality in numerical system and to ensure the justice of license test. In fact, nobody can guarantee that the simulators are feasible performance to use in license test. The simulator for train driver license test can be used effectively for studying of needed performance and quality to test new driver's skill. This study hopefully provides the base for improving the quality of the simulator for train driver's license test and contributes furthermore to improve the simulator development technology and railroad safety.
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경부고속열차(KTX) 제어시스템은 차량컴퓨터(OBCS), 차상신호제어장치(ATC), 견인제동추진장치(MBU), 운전자고장안내지원장치(TECA), 유무선통신장치(MDT), 보조전원제어장치(ABU), 공조장치(HVAC), 객차활주제어장치(TRAE), 도착지표시장치(PID), 객실안전및객실편의설비동작표시장치(FDTR) 등이 차량컴퓨터를 마스터로 그 외 하부제어장치들은 슬레이브로 다양한 시리얼라인을 매체로 상호 제어한다. 이런 다양한 시리얼링크라인의 물리적 구조와 상호 데이터 전송구조를 분석하기 위해, 시리얼라인 분석기를 다양한 방법으로 사용한다. 시리얼라인 분석기를 사용하기 위해서는 사전에 고속열차에 대한 전문 기술과 장비사용에 대한 경험이 필요하다. 공간과 환경이 어려운 여건에서, 고속열차정비에 근무하면서, 하부장치 시리얼라인 데이터 수집과정에서 얻은 물리적 접속방법과 통신데이타 분석에 대한 기본 구조를 제시하여, 관련 업무에 종사하는 분에게 도움이 되고자 한다. 또 한 향후 독자적으로 개발 된 고속열차 시운전과정에서 필요한 고속열차 진단업무에 도움이 되고자 한다.
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Nowadays, with urban railway vehicles, refrigeration has been used for a long time as an air conditioner including a heating apparatus and a ventilator. Regarding saveenergy, there are lots of researches continually on the refrigeration field to reduce the parts' weight, improve the parts' efficiency and make good looking design of air conditioners. Moreover, we are able to see the recent achievement of the researches. As a result, through this research we improve the quality of inner air with the urban railway system and make a domestic HVAC system by technical development of high capacity air conditioner and the principal parts.
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This paper is reviewed RAM(Reliability, Availability and Maintainability) data table utilized for RAM data management to Urban Maglev Transit. As railway systems become more complex, the RAM requirements are reinforced to ensure that a design meets Reliability, Availability, Maintainability criteria. Therefore, it needs the efficient management for RAM data of railway system to meet RAM target. At this study, RAM data management format is suggested to ensure reliability and maintainability based on acquired experience for overseas rolling stock. This RAM data table and FMECA(Failure Mode Effect Criticality Analysis) table are useful to the calculation of MTBF(Mean Time Between Failure), MTBSF(Mean Time Between Service Failure) and Maintainability. Also, this RAM management table will be efficient to improve the RAM evaluation to Urban Maglev Transit.
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Radio frequency identification, or RFID, is a generic term for technologies that use radio wave to automatically identify people or objects. UHF RFID technology is used for everything from tracking goods within their supply chain, working in process and for other applications. If RFID is applied in wheel scanner that is a important equipment to measure a diameter, width, height of wheel, efficiency in maintenance will be improved because of checking data in real-time. In domestic technology, capacity of wheel scanner technology as well as RFID are less good than foreign goods there a up to current day a point of read range, anti-collision, a tolerance. Therefore, sturdy on the development of wheel scanner using RFID technology to measure wheel in maintenance of rolling stock was carried out in this paper.
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IEC 62278 presents a process to implement a consistent approach to the management of reliability for railway applications. A reliability program has to be established at the outset of a project in order to manage reliability activities effectively through the life cycle. The first step of the reliability program is to evaluate reliability requirements and targets based on the system specifications. The system specifications are derived from the customer's needs. The way in which the system requirements reflect the customer's needs is strongly dependent on the characteristics of the product. In general the customer of commercial trains presents the system requirements from their needs. However, the relation between the customer and supplier is equivocal for a project to development a prototype train, and the reliability program should be different from that of an usual commercial project. This paper deals with a process to manage reliability activities for the development of a protype train based on the experiences obtained from the development of the Korea High-Speed Train: Hanvit-350.
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The Diesel Multiple Units (DMU) is a successful mass transportation system, that is being, continuously, on demand by train operators and railway authorities around the globe. One of its advantages is the fact that a diesel engine, along with the correct propulsion and control equipment. This paper describes a study on the Power Pack developed for Ireland DMU to help comprehensive concept of Diesel Propulsion System.
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Nowadays, with urban railway vehicles, refrigeration has been used for a long time as an air conditioner including a heating apparatus and a ventilator. Regarding saveenergy, there are lots of researches continually on the refrigeration field to reduce the parts' weight, improve the parts' efficiency and make good looking design of air conditioners. Moreover, we are able to see the recent achievement of the researches. As a result, through this research we will improve the quality of inner air with the urban railway system and make a domestic HVAC system by technical development of high capacity air conditioner and the principal parts.
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In order to solve the problem of traffic holdups and environmental pollution(contamination), several metropolises are operating the subway and many local government plans hereafter the light rail vehicle operation and it is in the process of preparing. This point of time, it need to evaluate the comfortable characteristic of the seat which is closely connected with passenger and it should be reflected to the product design through the data analysis. The methods of the comfortable characteristic evaluation should be considered to various methods from physical factor to psychological factor. Among these, the most universal and possible quantitative measurement estimate through 'Body pressure measurement system'. From this paper, it was measured the body pressure of the subway seat which is in the process of operating in a domestic and it will be compared and analyzed the material & seat shape, so we evaluated the comfortable characteristic of the short-distance transportation railway vehicle. It was operated the man and woman who belongs in standard shape of Korean, we compared and analyzed the Peak position where the body pressure is visible and body pressure spread out.
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The KTX, which have opened the revenue service in April 2004, is operating in Kyoung-Bu high-speed line and electrified conventional Ho-Nam line, and the more the electrification are enlarged, the more the requirement of operating of high speed train would be increased. In this paper, the result of test run and evaluation on the suitability of operating high speed train in electrified conventional line between Dae-jeon and East Dae-gu was reviewed. Evaluation and analysis was executed in specific categories, such as operation & running performance of the train considering vibration characteristics based on UIC 518, ride comfort and current collection, and response sensitivity of ATS device for signalling from track facility. The result of this running test was evaluated and considered as a good practice for revenue operation of high speed train in electrified conventional line between Dae-jeon and Dae-gu.
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Steering systems are classified as FWS(front-wheel steering), RWS(rear-wheel steering) and AWS(all-wheel steering) according to steering position. AWS is effective to reduce turning radius and platform length because all wheels are steered. Although various rear wheel control logics for AWS were developed, these are applied to four wheel steering cars. Therefore new control logics must be developed to apply articulated vehicles. In the present study, it is suggested how to control the real wheels based on the virtual rigid axles and also how to set it to minimize the turning radius.
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The electric train in the first line subway runs faster in the block from Suwon to Cheonan than the general block. The faster run results in the deterioration of ride quality due to the increase of noise and vibration. To reduce the noise and vibration of the electric train, a running test of the electric train was performed in the block from Suwon to Cheonan. The experimental results show that the sources of the noise and vibration basically comes from the irregularity of the railroad track and the connection part between car body and bogie. The possible countermeasure of the high speed electric train can be the reinforcement of the center pivot to have more flexibility and the frequent maintenance of electric train.
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This paper describes the variation of the critical speed of an urban railway vehicle according to the change of suspension characteristics. Suspensions of a railway vehicle are composed of primary and secondary suspensions. Generally, main focus of the stability analysis has been the primary suspension. However, secondary suspension has large effects on the stability as well as the ride quality of a vehicle. In this paper, stability of an urban railway vehicle is discussed in relation to the variation of characteristics of both primary and secondary suspension. For this, modal analysis is carried out using a linear dynamic model of a half vehicle and a polynomial fit for Kalker's creep coefficients. Stability along with change of the effective conicity of a wheel is also investigated.
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Floating floors, which are mainly used for reducing interior noise levels of railway vehicle, are known to be superior to single structure in respect to sound transmission loss and vibration reduction performances. The stiffness of isolator is one of the important design variables in floating floors. From modal tests, modal properties of underframe, top floor and isolators are derived. They are used as input parameters for predicting structure-borne noise using AUTOSEA.
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To develop the most effect maintenance system of urban MAGLEV train which is being developed based on system engineering, logistics belong to special system engineering were applied to maintenance system and Integrated Logistic Supports (ILS) were employed to tailor every step of MAGLEV project. Since ILS had not been applied to domestic train project, the followings were studied to validate ILS: 1) case studies on maintenance procedures at home and abroad, 2) overview of standardized process of ILS, 3) Comparison and analysis of relationship between RAMS and ILS, 4) Application of ILS to MAGLEV maintenance system and other domestic train system.
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Generally railway vehicle runs on the rail with endless interaction between wheel and rail. Irregularity of rail causes the periodic motion of the vehicle. In association with this motion, the design of vehicle would be carried out in order to avoid the resonance between car-body and bogie. It may be seen that the first vertical bending mode of car-body contributes considerably to the vertical ride comfort level. In this paper to know the effect of the car-body first vertical bending mode on vertical ride comfort, the mode has been considered with dynamic model. I-DEAS program was used to get the car-body first vertical bending mode and VAMPIRE program was used to analyze ride comfort index(Wz) with FE interface file.
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The riding comfort and the durability of train are effected by the rail irregularities such as track gauge, superelevation, alignment, longitudinal level, twist, cant and cross level. Inspection and estimation of irregularities are very important to maintain the rail condition. Generally, the EM120 has been utilized to measure the rail irregularities once a month in Korea. However, the EM120 can be operated at night time only, because the inspection speed of EM120 is much slower than the speed of high-speed trains. Also, the EM120 is too slow to inspect effectively for the whole commercial line. Therefore, we have mounted the track inspection system on the High-Speed Rolling Stock 350 eXperimental (HSR350X) and measured the rail irregularities to confirm the condition of a rail while running 300km/h. In this paper, the track inspection system mounted on HSR350X is mainly considered, and the measured results through test run are introduced.
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A bi-modal tram has been developed to offer an advanced transportation service compared with existing vehicles. The All-Wheel-Steering system is applied to the bi-modal tram to satisfy the required steering performance because the bi-modal tram has extended length and articulated mechanism. An ECU for the steering system is essential to steer wheels on 2nd and 3rd axles by the specific AWS algorithm with the prescribed driving condition. The Hardware-In-the-Loop Simulation(HILS) system is planned for the purpose of evaluating the steering system of the bi-modal tram. There are kinematic links with the hydraulic actuator to steer wheels on each 2nd and 3rd axles and also same steering mechanism as the actual vehicle is in the HILS system. Controlling the movement of hydraulic actuator which reflects the lateral steering reaction force on each wheel is the key to realize the HILS system, but the reaction force is continuously changed according to various driving conditions. Therefore, the simulation through the multi-body dynamics model is used to obtain the required forces.
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The irregularities in the guideways used in the Maglev transportation system that result from surface roughness and deflection of guideway have strong effects on the dynamic characteristics of Maglev vehicles, because the electromagnetic suspension of Maglev vehicles strongly interacts with the guideway. For this reason, a numerical prediction of air gap responses to these irregularities is desirable to improve aspects of running performance, such as stability and passenger comfort, while minimizing aesthetic impact and construction cost. This paper presents a procedure to predict the air gap response which is a criteria for stability, and investigates the responses with the goal of attaining higher travel speeds in the urban Maglev vehicle UTM-01 utilizing electromagnetic suspension.
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Roller rigs have been built widely to study and evaluate the dynamic behaviors of railway vehicles, and they have particularly been applied to the development and routine maintenance of high-speed trains. However, there is no roller rig for routine maintenances of high speed train in Korea, although high speed train is running on the lines. Therefore, it is very important issue to check and evaluate the dynamic responses of high speed train after several years of operation. This paper presents a study on the conceptual design and dynamic model to develop the roller rig for the routine maintenances of high speed trains. The roller rig has two independent electronic motor and maximum speed of 350km/h, which can simulate running on straight and curved track. CATIA V5 was used to design the 3D geometrical models and ADAMS was used to verify and analyze the dynamic behaviors of roller rig.
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The performance of the railway bogie is classified into the stability and the steering performance. Testing for the bogie stability is conducted on the roller rig. But testing for the bogie steering performance on test facility is very difficult, so the testing for the vehicle curving performance is conducted on the real curve track. And it is desirable to test on the full scale test rig, but it caused many problems relating to test costs, test time. To overcome these problems, the small scale test rig is actively used in the field of bogie stability. Thus, in this paper, we have studied the scale track to test the bogie steering performance. For this, we designed the 1/5 scale test track equivalent to radius 200 curve and confirmed the validity of the testing for the bogie steering performance on the scale curve track through the testing using 1/5 scale bogie.
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The running safety of rolling stock is assessed by derailment coefficient. It requires lots of preparatory time, expenditure and high measurement technique to measure derailment coefficient. If derailment coefficient could be measured when track or vehicle is maintained, safety will be improved. The measurement and assessment of running safety is necessary for safety especially for the vehicles newly developed and started service. Therefore measurement of derailment coefficient is most important thing to secure running safety. In this paper, we examined new assessment method which could estimate derailment coefficient by measuring vibration acceleration and displacement of vehicle operating at actual track irrespective of time and place. The new method could be used effectively as a mean confirming running safety.
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고속철도는 일반철도와는 달리 터널구간에서 여러 가지 공기역학적인 문제가 발생한다. 개활지와 비교하여 크기가 매우 작은 터널에서 고속으로 운행하는 열차는 큰 공기저항을 받게 되어 주행 안정성이 떨어지고, 터널 내의 급격한 압력변동으로 객차 내 승객의 이명감 발생, 터널출구에서의 소음공해 등 일반철도에서는 예상치 못했던 문제를 유발시킨다. 이 같은 문제점을 해결하기 위하여 본 고에서는 공기압의 특성 분석에 대하여 소개하고자 한다. 수치시뮬레이션을 통해 이명감 기준을 만족하는 최적의 단면을 검토하였다. 또한, 경부고속철도를 운행하는 열차에서 객차내 압력을 측정하였고, 화신5터널에서 터널내 압력 및 터널출구에서의 미기압을 측정하였다. 동시에 열차주행 모형실험을 수행하여 수치시뮬레이션의 입력조건으로 사용된 각종 매개변수 등의 적정성을 비교 검증하였다.
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This paper is about the examination and selection of the special method applied to the railway tunnel which will lie under the road. Moreover, the road was constructed on the weak ground. Eventually, we select DSM, considering geological condition, stability during construction of the railway tunnel, and economic efficiency. The 3D-analysis, performed with PENTAGON-3D and MIDAS CIVIL-3D, shows that allowable standards are all satisfied. In the design of the railroad tunnel under the road at low depth, this paper will give useful data for the selection of the tunneling method.
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The research which it sees will confront to the coating with paint material and a coating with paint public law application of the river bridge and it will present it will sleep and it will execute, it will reach and a comparison - an analysis from the research which it tries to respect middle of special environment the polyurethane system which is a method coating with paint system and fluorine resin system, against a ceramic system it executed more an objectivity and rational fundamental data. With research method against each coating with paint evening sunlight a research investigation material and structure, it separated with spatial-temporal characteristic and economic viewpoint it executed. When considering overview from material viewpoint, fluorine resin system ceramic system polyurethane system pure with it is judged with the fact that it is excellent. There is a possibility of saying that the coefficient of friction of the fluorine resin system which uses the weapon quality zinc end coating compound ever so hard and polyurethane system is excellent ceramic system than from structure viewpoint. That fluorine resin system = polyurethane system ceramic system pure with it is excellent, it is judged from spatial-temporal characteristic viewpoint. It measures but it considered an internal troubles year grudge in the standard which becomes disturbance the place where it executes the market the expectation life person of the general bridge against 100 years the result fluorine resin system polyurethane system ceramic system which compares a materials unit cost pure with it appeared.
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It is essential to reduce track maintenance costs and to extend the periodic replacements of continuous welded rails based on accumulated passing tonnage. As recently train load decrease and rail joints wear down less, the periodic replacements of continuous welded rails can be extended. There are many kinds of rail damage like squat, head-check and corrugation. These can be taken nondestructive or naked eye test. So the periodic replacements of continuous welded rails based on accumulated passing tonnage were examine with focusing on a crack of rail bottom of continuous welded rail. Therefore, this study measure dynamic response of track by metro train load, it compute impact coefficient and track spring coefficient for estimating a condition of actual track system. Also, it is converted the measured stress waveform into stress frequency histogram by the rain-flow counting methods, and then the equivalence of stress is calculated. As apply s-n curve of a new welded rail, accumulated fatigue damage ratio of laid rail and remaining service lives is estimated. This study suggest a plan of the periodic replacements of continuous welded rails based on accumulated passing tonnage classified by the types of track system.
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Foundation settlements(settlements at the embankment surface and ground) has been evaluating to satisfy the strict allowable residual settlement level from the start of the construction of Gyungbu high speed railway. This is because both embankment and ground settlement could be important to minimize the residual settlement after the construction of concrete track. Ground settlement is caused by the increase of effective stress resulting from embankment. The causes of embankment settlement could be come from different sources, for example, the increase of effective stress, rainfall, creep behaviors. Based on the field measured data, this paper analysed the settlement of ground and embankment settlement. The biggest settlement at the embankment surface was 9.7mm during 246days at the STA 000k922.5. The calculated settlement of embankment itself was 8.6mm at the same places. These results conclude that the compressive settlement of embankment could not negligible.
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This paper describes a study to determine proper escape way interval for the design phase of single bored double track tunnel. Among many methods which determine escape way interval, we choose a QRA(Quantitative Risk Analysis) method. But a different method must be chosen differ from other country because of special design situation of Korea. So, it is necessary to develop a method which considers a special design condition of Korea. Because fire accidents of railway tunnel are a rare event, simulated situation can be produced by CFD simulation and evacuation analysis simulation. However, it is generally difficult to estimate of fatalities from these methods, so a concept of FED is introduced to estimate of fatalities. Quantification process provides effective results for practical design stage and the result were employed in design.
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The importance of maintenance of rail surface defects is increasing more according to the KTX operation. That is because during high speed operation of rolling stock, rail surface defects may cause shortened fatigue life of rail, acceleration of track degradation and reduced ride comfort. The paper was intended to study the establishment of rail grinding criteria of high-speed railway lines considering the KTX operation circumstances. For this, the specimens of UIC 60 rail on Kyeong-Bu high-speed operation lines were collected and they were analyzed for metallographic structure and tested for the hardness. By analyzing the test results to the factors affecting the RCF causing the defects of rail surface, the study suggested the rail grinding criteria of the domestic high speed railway lines. As the factors affecting RCF, passing tonnage, running speed and track condition are considered.
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Due to the transportability problems, long rail shall be from base rail unit, which is normally 100m for regular rail and 300m for high speed rail. After these rail units are transported from the fabricator to the site, the field weld would be performed.axial stresses in the long rail is mainly from the temperature differences at various locations the long rail. Also the gaps between each welds cause secondary axial stresses in the rail. In addition to these, re-welds the fractured rails, rail buckling, irregular rail vibration, rail twist also result innonuniform axial stresses in the rail. To obtain the rail buckling stability, the rail stresses shall be released due to the resetting of CWR. Traditionally two resetting of CWR methods have been applied, the one is rail heater and the other is rail tenser. these methods, the latter has been recommended because it has less limitation in the rail length and it is easier to minimized the force differences. But even in this method, the calculation is cumbersome and is not easy to find out the rail stress distribution itself.refined methodsxial stress resetting in the long rail is studied and this study be easily applied in the real construction. From this approach, more rational rail maintenance system can be expected.
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LRT(Light Railway Train), which is a intermediate system of train and bus, is arose for the solution of subway construction cost and the transportation capacity of bus. LRT was introduced in 1980's. About 30 local governments are plan to introduce LRT or constructing LRT, at present. AGT(Automated Guide-way Transit) system, which is a kind of LRT, is operated without driver. Rubber wheeled AGT system can reduce the noise and vibration compare to steel wheeled AGT, so it is estimated as ideal transportation system for urban area. And live loads at bridge are classified as the static load of vehicle and the dynamic wheel contact load which is occurred from the interaction of bridge and vehicle vibration, and the surface roughness. In the case of AGT system, the dynamic increment factor of bridge is greater than the normal train bridge and roadway bridge, because, the weight of AGT vehicle is more light that the train of truck. The exact method for dynamic increment factor is experiment. But this method is needed much money and time, moreover, this method cannot be adopted in design. Therefore, a simulation program for the interaction of AGT bridge, vehicle and surface roughness was developed, in this study. And the program was verified by experiment. As a result, the accuracy of the simulation program can be verified.
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Form the application of long rail system the non-ballast steel plate bridges, fatigue strength increase and rail noise reduction can be expected. This is mainly form the reduction of the rail impact at the rail joint locations which already made to behave together from welds. In the high speed rail, application of long rail system is essential because without long rail system, the required serviceability level can not be achieved. But even with this long rail systems, the thermal expansion from the girder can not be absorbed in the normal bearing systems, and these expansion cause between girder and rail. Also unexpected rail buckling and fracture through rail thermal tension may happen. It was found through numerical analysis and field measurement that these problems can be avoided by semi-fixed bearing system. In this study, the benefits of non-ballast plate bridge through long rail system, especially at the point of girder stability, girder stiffness increase and bearing maintenance will be reviewed.
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To analyze dynamic and long-term behavior of high speed rail system, and seismic measurements been installed at the various locations in the high speed rail system. Among these, 76 measurements were installed Chunan and Deajeon, and 80 measurements between Kwangmyung and Chunan. From these 156 measurements, real time data are continuously corrected and be sent to the main monitoring system to be used further analysis. These two systems were installed by different institution, and so there are not only basic differences in the system itself, but system running methods and data collecting/transferring methodology. There has been systematic difficulties due to these differences. This study shows the whole steps of high speed rail data monitoring systems include measurement equipment itself and data collecting/transferring system. study will proposed a more effective methods for collecting. This study also discuss the real time analysis method which can be used for future high speed rail monitoring system.
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The track and rail surface geometry is of prime importance on the requirement for track dynamic stiffness, particularly for the speed of 350 km/h, for which both the requirement for fatigue and tensile strength limits require a lower stiffness than 100 kN/mm, which is near the value for ballasted track. However, the track quality has been considered as being the same for 350 km/h as that for 300 km/h, and based on ballasted track, and the track geometry may be kept in better condition with a slab track(probably more similar to the medium quality track geometry of ballasted track). In conclusion, under the condition that the track geometry quality provided by the concrete slab system is fairly good, and that the required maintenance is applied to the rail surface, there would be no safety risk if the fastening system point stiffness reaches 160 kN/mm for 300 km/h operation, and 110 N/mm at 350 km/h.
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Any track system needs major changes of its components during its life. The most economical solution is, if possible, to make all components reach their life limit during the major track rehabilitation operation. Usually, the rail does a role as the driving component for the objective: its life-time is equivalent to around 500 million tons of traffic on high speed lines. On the KTX line with 110 trains per day, this would correspond to around 16 years, which is probably too long for the elastic pads of a concrete slab track. The most economical solution should be to change them at an intermediate step of 8 years, without changing the rail, and then to change both the rail and elastic pad at 16 years intervals (some rail changes on the South East TGV line in France began 15 years after service opening at 260 km/h, but recent rails have better characteristics).
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Korean trains pass many mountain areas, so the volume of structures like bridge and tunnel has large part of railway lines. Train speed-up naturally needs a straight line in railway, then structures are increasing, and this influences passenger's comfort and the safety of operation, and it needs more track maintenance. The stiffness of bridge and tunnel is higher than the soil in the roadbed in spite of dynamic difference in vibration and displacement. Differences in stiffness have more dynamic effects and increase the deformation and destruction in the track and roadbed. This study will measure periodically to structure's approaches which have very fast track irregularity and analyze dynamic differences and track irregularity near structure's approaches, so realize the cause of track irregularity of structure's approaches and use basic data for reasonably strengthening method of structure's approaches.
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AGT system is a kind of light railway train. AGT system use of concrete track and rubber tire, so it can be reduce the noise and vibration, compare to the normal train system. And, the dynamic responses of normal bridge are influenced by the dynamic characteristics of bridge, the speed of vehicle and the surface roughness of railway. But the AGT system bridge is influenced not only the above facts but also the guiderail unevenness, because, AGT vehicle steered by guiderail. So, in this study, optimized service condition is suggested for the design and operation of AGT system, by the means of experimental study. The experiments are executed for PSC bridge with length of 30m, at the AGT test line in Kyongsan. The test results are compared and investigated according to the prominence. In the test result, the guiderail prominence influenced on the dynamic response of bridge. It shows a increase as compared with no guiderail prominence in the dynamic response value acceleration, displacement, stain.
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Recently, the continuous welded rail(CWR) track has been used for less maintenance of the High-speed railway tracks. In case of CWR track, track buckling has always been an unpredictable event under the high compressive stress in rail. The behavior and stress state of CWR track is manily influenced by its thermal variations, and it is important to understand seasonal variations of rail temperature and stress to predict the track stability. This paper describes the in-site measurement for the rail temperature and rail stress, and the correlation between the rail temperature and stress was examined.
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From the research which it sees verification of the whole interpretation and local interpretation of the durability steel deck bridge a static test and it produces the test body which it sells with character and it executes smallness pul lek detailed interpretation it leads and the appropriate characteristic of smallness pul lek detailed interpretation and to sleep a nominal stress price and it compares it judges it does. The stress quality from each structure region which it follows in load stock location it analyzes and from the hazard which evaluates, the objective region the length rib and the bottom grater weld zone, the length rib and width rib connection department and the width rib with the father it divided. It investigated the stress distribution of the test body from these objective location, FEM interpretation it led and the conduct against each structure state tax it analyzed. General conduct the load stock location the floor plate is located in the center with interpretation price together symmetry characteristic to seem, it cannot be like that it cannot there is one actual test price. Like this reason the length rib and width rib connection actually production even production characteristic security it is a day when it is impossible with the curvature junction department which it blows, it follows in examination body deferment condition and form feed with the fact that it is visible a big difference even with error of some it becomes. Consequently for a data and the research which are more accurate it is judged with the fact that the effort which is prudent will be necessary.
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The Steel deck a structural analysis in head plate form change the objective bridge which it sells it accomplished a detailed structural analysis from the research which it sees and Bulk-head plate it accomplished. The length rib where the fatigue crack which is considerable generally occurs, width rib connection department and the length rib side, the width rib side it compares principal stress in the object and it does to sleep. It applied the grudge element model which it describes consequently after words and a load and a boundary condition and it executed it compared a static test and principal stress. It grasped the stress conduct of the The Steel deck petal which it follows in hand weaving rib affix location and the affix location to sleep in order to analyze a same location Bulk-head the head and comparison considered. From the detailed section which is reinforced with the stress investigation result hand weaving rib of the location which is weak in structural analysis result fatigue crack of form star reinforcement details basic form and Bulk-head the form which is reinforced with the head plate compared to principal stress investigation hour it is judged at the section which separates most.
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The selection of the support system is an important design parameter in design and construction of the tunnel using the new Australian tunnel method. It is a common practice to select the support based on the rock mass grade, in which the rock mass is classified into five rock groups. The method is applicable if the characteristics of the rock mass are uniform in the vertical direction. However, such case is seldom encountered in practice and not applicable when the properties vary along the vertical direction. This study performs comprehensive three dimensional finite difference analyses to investigate the ground deformation pattern for cases in which the rock mass properties change in the vertical direction of the tunnel axis. The numerically calculated displacements at the tunnel crown show that the displacement is highly dependent on the stiffness contrast of the rock masses. The results strongly indicate the need to select the support type
$0.5{\sim}1.0D$ (vertical direction) on the rock mass boundary. The paper proposes a new guideline for selecting the support type based the results of the analyses. -
기존 노선의 속도향상에 따른 궤도 유지보수비의 절감을 위하여 여러 철도 선진국에서는 다양한 형태의 궤도를 고안하여 사용하고 있지만 현재까지 우리나라의 경우 대부분의 선로는 자갈도상이다. 그러나 현재 국철 및 지하철의 경우 장기사용에 따라 자갈도상기능이 급격히 저하되고 연간 증가되고 있는 열차운행 통과톤수로 인하여 장 단기적인 궤도유지관리에 문제점이 발생하고 있다. 또한 자갈도상 궤도는 자갈마모, 궤도틀림 및 균일하지 않은 궤도지지 강성 등의 문제점으로 인하여 막대한 유지보수 비용이 사용되고 있다. 철도교량상 자갈도상 궤도는 교량과 궤도의 상호작용으로 인하여 자갈도상의 노후화 진전속도가 일반 토노반 및 지하, 터널구간보다 빠르며 이러한 궤도의 노후화는 열차하중의 동적 충격하중을 증폭시켜 궤도 및 교량의 부담력을 증가시키게 된다. 또한 교량상 자갈도상 궤도가 노후되어 하중분산 및 진동감쇠 등과 같은 정상적인 자갈도상 궤도로서의 역할을 수행하지 못하게 된다면 교량이 부담하는 정, 동적하중의 영향이 더욱 가중되고 이는 교량의 거동특성에 영향을 미치게 된다. 따라서 적정 수준의 궤도상태를 유지함으로써 궤도의 적정탄성력을 확보하고 이를 통해 교량의 동적하중부담을 저감시키는 것이 중요하다. 그러나 현행 철도교량 설계 시 적용하는 궤도의 영향은 고정하중으로만 고려되어, 이러한 자갈도상 궤도의 탄성거동 영향이 반영되지 못하는 실정이다. 따라서, 본 연구에서는 철도교량의 동적거동 특성을 감안한 교량상 자갈도상 궤도의 탄성력을 추정하고자 공용중인 철도교량 및 자갈도상궤도에 대한 현장측정 및 해석을 통하여 실교량의 동적응답특성을 유발하는 운행선 자갈도상 궤도의 탄성력을 추정하고, 자갈도상궤도의 탄성력변화가 철도교량의 동적거동에 미치는 영향을 검토하였다. 그 발현이 미약하거나 나타나지 않았다. 이상의 결과를 종합하여 FS-s2, FS-s5, FS-s18 및 Fs-s22 유전자들은 대부분이 기능이 거의 알려져 있지 않는 것들로 기능력의 변화 과정에서 중요한 역할을 할 것으로 생각되나 앞으로 보완 연구를 통하여 각 각의 유전자들의 보다 정확한 기능을 이해하는 것이 필요 할 것으로 사료된다.led sealant의 사용이 바람직하다고 생각된다. 그러나 미세누출에 있어 교합력을 고려한 실험이나 장기간의 임상실험이 필요할 것이다.5).vac/PE필름은 장기저장시 사용이 좋을 것으로 사료된다. 2) 질소가스 및 탄산가스투과도 각각
$61.6{\mu}PVDC/PE/Al-vac/CPS\;12.5,\;59.8>96.9{\mu}PE/PVDC/PE\;7.1,\;42.0>79.3{\mu}ET/PVDC/L-LDPE\;6.4,\;34.2>72.2{\mu}PET/PVDC/PE/Al-vac/PE\;0.74,\;4.2cc/m^2.24hr{\cdot}atm$ 으로 가장 우수한 PET/PVDC/PE/Al-vac/PE 복합필름이 장기저장용으로 이용이 좋을 것으로 사료된다.태발생을 연구하는데 기초적인 자료로 활용될 수 있을 것으로 사료된다. 조사한 결과 유의확률이 0.05 이하인 수치들은 Hb과 Albumin, K, Na간, Neutrophil과 Leukocyte간이었고 상관계 수치는$0.370{\sim}0.442$ 사이로 나타났다. 유의확률 0.01이하로 조사된 수치는 Cholesterol과 ALT간, LDH와 Platelet, Creatinine간, Platelet와 BUN간, Na와 K수치간 이었으며 상관계수는$0.531{\sim}0.866$ 사이로 나타났다. 5. 농양 -
The ballast, one of a track components, plays an essential role as intermedium in transmitting train traffic-load to subgrade safely, and deterioration of ballast caused by cumulative load effects growth of track irregularity. Especially in the case of Gyeongbu high-speed railway, the deteriorating speed of ballast by dynamic vibration is faster than conventional line because KTX is longer than normal trains in length and it's velocity is very fast with high speed of 300km/h as well. In addition, ballast is a nonlinear material contrary to ordinary metal which has homogeneous property and this property of ballast may cause transformation of ballast. Therefore the theoretical modeling of ballast is quite complicated and it is hard to ensure the reliability of the result. The objective of this paper is to examine the availability of GPR(Ground Penetrating Radar) in estimating the thickness and the degree of deterioration of ballast. First, We figured out the principle of GPR which is the technique of evaluating the condition of ballast and then analyzed data which were measured at Gyeongbu high-speed railway where KTX is running now.
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Database are developed to control measured settlement data under construction in Gyungbu High Speed Railway from Daegu to Busan. This means that data having different type at different site could be managed in a unified way. The database includes algorithm to evaluate embankment settlement with settlement data at the surface of embankment and ground settlement data. And also, it has a function to analyse the causes of large settlement over allowable level and high settlement speed based on the log data, embankment specification, physical characteristics of embankment materials.
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Concrete track will be constructed in Gyungbu High Speed Railway II(GHSR II) stage construction site from Daegu to Busan. Concrete track is supported by substructure consisting of the original ground and embankment and does not allow the settlement of track because of its structural type. The embankment is composed of rock and soil mixture and settlement is feasible. So management of settlement of embankment is key point in successful construction of the concrete track. Compaction management of mixed fill materials is important in minimizing the settlement of embankment. In this study, in order to assess the compaction characteristics of mixed fill materials, large laboratory compaction tests were conducted. Mixed fill materials were obtained from two construction sites in GHSR II construction site. Modeled mixed fill materials having different rock type, fine content, maximum particle diameter, and moisture contents were prepared. From the test results, compaction characteristics of mixed fill materials were analysed.
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Rubber wheeled AGT(Automated Guide-way Transit) system is a prominence transportation system for urban area, because of its low construction cost and management, low noise and vibration and fine exterior view. AGT system uses concrete tracks. Concrete can be easily damaged by the impact, change of temperature and external loads. The fault of concrete track is harmful not only to riding quality but also to bridge. Therefore, in this study, the effects of railway prominence to the bridge are surveyed by experimental method. The experiment was executed for PSC bridge at AGT test line in Kyungsan. And the test results for 5mm, 10mm prominence and without prominence are compared and investigated, according to the vehicle speed.
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곡선부 열차주행시 궤도에 작용하는 횡압은 궤도 변형과 차량손상 및 유지보수 비용 증가를 초래하며 특히 곡선부 레일의 편마모 및 열화손상에 직접적인 영향을 미친다. 그러나 국내외적으로 이러한 레일손상에 미치는 여러요인에 대한 기존의 연구는 선형, 차량조건, 운전속도 및 운전습관 등에 집중되어 있으며 궤도구조의 특성(탄성력, 유지관리 등)에 관한 것은 간과하고 있는 실정이다. 또한 자갈도상 궤도구조에서 도상 횡저항력이라 부르는 궤도의 횡탄성이 콘크리트 궤도에서는 특별히 없기 때문에 일반적으로 콘크리트 궤도구조가 자갈도상 궤도보다 마모로 인한 레일 교체주기가 약 2배 짧은 것으로 기존의 연구결과 나타났으며, 국내 콘크리트 궤도 설계 및 운영 실적 검토결과 콘크리트 궤도의 궤도탄성력이 자갈도상보다 부족하여 레일 및 궤도손상을 가중 시키고 있는 것으로 나타났다. 일반적으로 콘크리트 궤도는 자갈도상 궤도에 비해 궤도의 탄성조정이 유리하며 유럽의 경우 콘크리트 궤도 설계 시 자갈도상의 수직 탄성력 범위와 동등이상의 성능확보를 권고하고 있으나 국내외적으로 궤도의 횡탄성에 대한 검토는 미약한 수준이다. 따라서 본 연구에서는 운행선 궤도에서의 현장측정 및 유지관리실적 분석을 통해 공용중인 자갈도상 및 콘크리트 궤도의 동적거동 특성을 파악하여 운행선 궤도의 탄성력을 유추하고 궤도시스템별 궤도 탄성력과 레일 손상과의 상관관계 및 곡선부 레일 손상에 미치는 궤도 횡탄성의 영향을 실험적으로 입증하여 콘크리트 궤도의 적정 탄성 수준 및 자갈도상 궤도의 도상탄성 확보의 중요성을 제시하고자 한다.고리즘 보다 DNA 염기 서열 배치에 있어서 효율적임을 확인하였다.첨의 폐쇄를 유도할 수 있었고 이런 점을 이용 외과적 술식을 피할 수 있었다. 2군 사이에는 통계학적 차이가 없었다(p>0.05). 4. 치은면에서
$Oraseal^{(R)}$ 을 이용하여 수복한 3군이 1, 2군보다 통계학적으로 더 낮은 미세누출 정도를 보였다(p<0.05).하였다. 생징후의 경우 각 군 모두 정상범위 내에서 안정된 양상을 보였으나, 개구기 삽입이나 국소마취 단계에서 발생하는 자극에 대한 말초 동맥혈 산소포화도와 심박수의 반응정도가 I군에 비해 II군에서 낮게 나타났다(p<0.05). 임상적으로 바람직한 행동양상(Q : Quiet)의 비율이 III군에 비해 II군에서 높게 나타났으며(p<0.05), II군과 I군간에는 유의한 차이를 보이지 않았다 (p>0.05). 본 실험에서 시도한 두 가지 진정요법이 비교적 높은 임상적 치료 성공률(II군 : 97.14%, III군 : 88.57%)을 보여 만족할 만한 결과를 나타낸 것으로 평가되었다.tosan film보다 큰 수증기 투과도를 보였다.적으로 유의한 차이를 보이지 않았다.y tissue layer thinning은 3 군모두에서 관찰되었고 항암 3 일군이 가장 심하게 나타났다. 이상의 실험결과를 보면 술전 항암제투여가 초기에 시행한 경우에는 조직의 치유에 초기 5 일정도까지는 영향을 미치나 7 일이 지나면 정상범주로 회복함을 알수 있었고 실험결과 항암제 투여후 3 일째 피판 형성한 군에서 피판치유가 늦어진 것으로 관찰되어 인체에서 -
After rapid running is begun in domestic, problem by the train gust that was not considered at existent train running appeared. If the High-Speed railway business speed rises by 350km/h in the future, is going to become more big problem. This study conducts an experiment that measure in local about KTX train beside Gyeong-Bu High speed railroad track about aerodynamics effect that happen by passage of train and analyzed. In case KTX II runs with the 350km/h speed, forecasted effect that get in the simple vertical surfaces parallel to tracks according to distance from rail center. Compared construction size with structural analysis in case do not consider with case that consider the train gust about sound proof walls representatively. As a result, proposed wind load standard that apply at sound proof walls design.
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The objective of this paper is to suggest a characteristics of Noise and the Noise Prediction Model and the appropriate Noise Impact Mitigation Method for a elevated railway bridges construction. The characteristics on noises are investigated and evaluated according to a type of railway bridges such as steel, concrete and steel/concrete compound bridges, a types of train, a distance and height from railways. The noise prediction study has been made by the evaluation of differences between model values and in-situ measurement, around the railways. For the noise prediction, the Mithra program and the electronic properties of noises have been adopted.
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본 논문은 도시철도공사 시 하저통과구간의 지반투수저하공법에 대한 연구결과이다. 본 연구에서는 하저지반의 투수저하공법들 중 특히 주입공법에 대하여 연구의 초점을 두었다. 이에 따라 하저지반 투수저하를 위하여 적용되고 있는 기존주입공법들의 이론적 배경과 시공방법들을 문헌과 시공사례자료 등을 고찰하여 비교 분석하였다. 이와 같이 다양한 고찰을 통하여 주입공법들을 하저통과 도시철도터널 안전시공 측면에서 평가하였다. 또한 분석 결과로부터 하저지반에서 장단기적으로 안전하게 지반수리거동을 도모하기위한 주입공법의 설계기법에 대하여 제시하였다. 이와 같이 하저지반 투수저하주입공법들의 평가결과를 근거로 하저통과 터널공사 시 안전시공과 완공 후 터널구조물의 장기적인 안전유지관리 측면에서 적용성이 양호하다고 판단되는 N.D.S(Natural Durable Stabilizer)공법과 S.M.I(Space-Multi- Injection Grouting) 공법을 제시하였다. 그러나 이 두공법의 실질적인 시공효과를 평가하기위하여 OO지역에 건설예정인 하저통과 도시철도터널공사구간에서 시험시공을 실시하였다. 시험시공기간 중에는 실내 및 현장에서 지반투수특성시험을 실시하여 시공전후의 지반의 투수성저하효과를 평가하였으며, 두공법의 시험시공결과는 이론적인 배경과 함께 비교 분석하였다. 결론적으로 S.M.I공법의 경우 N.D.S공법보다 투수성 저하효과가 큰 것으로 나타났다. 즉, 주입공법에 있어서 시멘트 무기질계 재료보다는 비 알카리성 실리카 졸계가 투수저하 효과를 더 크게 할 수 있을 것으로 판단되었다. 끝으로 본 연구결과로부터 특히 철도터널설계시 하저지반의 투수저하 증대를 위한 주입공법 설계기술발전에 공헌 할 것이다. 값을 가지며 표준 편차가 작았다 PR와
$SpO_2$ 는 두 그룹 모두 정상범위내의 값을 보였다. 점막하 주사를 이용한 Midazolam의 추가 투여는 안전성을 크게 침해하지 않는 범위 내에서 진정 깊이를 깊게 해주며 안정적인 진정을 이루게 함으로써 보다 바람직한 진정을 유도해 줄 수 있는 것으로 사료된다.보이지 않았다.tag의 표면에 형성된 뚜렷한 측부 가지들도 발견되었다.}60cm$에 위치시켜 표면선량의 over dose나 under dose의 발생 방지를 위한 주의가 반드시 필요하겠다.군의 전단결합강도가 가장 낮았다.본에서 III군에 비해 크기가 큰 기포가 더욱 많이 관찰되었다.e의 약동학은 cimetidine에 의해 유의한 차이를 보였으며 CYP1A2유전자형에 따른 영향은 관찰할 수 없었다. CYP1A2유전자형에 따른 생체내 대사능을 관찰하는 실험이 향후 이루어 져야 할 것으로 사료된다.san film보다 큰 수증기 투과도를 보였다.적으로 유의한 차이를 보이지 않았다.y tissue layer thinning은 3 군모두에서 관찰되었고 항암 3 일군이 가장 심하게 나타났다. 이상의 실험결과를 보면 술전 항암제투여가 초기에 시행한 경우에는 조직의 치유에 초기 5 일정도까지는 영향을 미치나 7 일이 지나면 정상범주로 회복함을 알수 있었고 실험결과 항암제 투여후 3 일째 피판 형성한 군에서 피판치유가 늦어진 것으로 관찰되어 인체에서 항암 투여후 수술시기는 인체면역계가 회복하는 시기를 3주이상 경과후 적어도 4주째 수술시기를 정하는 것이 유리하리라 생각되었다.한 복합레진은 개발의 초기단계이며, 물성의 증가를 위한 연구가 필요할 것으로 사료된다.또 다른 약물인 glyc -
Walking passenger injury accidents in and around stations have increased in recent years, and passengers are now more aware of being able to claim compensation for such accidents. Therefore, it is anticipated that station managers and owners will need to take measures to improve the condition of walking areas so that performance objectives are met an the compensation paid for passenger accidents is limited. The aim of this study covers the following: accidents statics and contributory factors, station flooring and footway material, guidance for flooring, and test methods for slipperiness and surface profile.
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The construction of concrete slab track system is increased because the system has advantages which are maintenance free and so on, the other side, the system has weak points such as increase of the cost of the early stage construction and noise levels. Currently, concrete slab track systems has been designed for Gyungbu high speed line stage 2 and Honam high speed line. For those tracks, noise absorbing blocks are considered. Therefore, test methods and proper criteria for structural performance and reduction efficiency of noise absorbing blocks are required. The aim of this study is to provide provisons for installing acoustic-absorptive block on slab tracks.
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The paper presents an application of the model to a practical problem of train-induced vibrations. The aim of this study is to vertify for performance of isolators which was developed in KRRI supported floating slab track. Laboratory tests on developed isolations show that the energy dissipation, under cyclic loading of constant amplitude, can be suitably represented by a combination of a viscous and a hysteretic damping. Also, other tests for structural performance are carried out, such as elastic material test, compression test and so on. The specimen,
$400{\times}400{\times}300mm$ , is placed between two stiff steel plates designed to uniformly distribute the compression stress on the surface. -
As the volume of traffic in southern part of the republic of Korea grew, expansion of transportation was required. In that purpose, the railway between Samnangjin and Gwangyang is being extended to a double-track line. This construction includes Nakdong bridge located across Nakdong river. This truss bridge is constructed in incremental launching method (ILM) and composed of two sections, straight line and curved one. Bridge construction in the method goes with the shift of roller supports which results in the change of structural system. To accomplish safe construction, the measurement during the whole launching stages. The locations of member in severe condition and the corresponding response values were estimated through the preliminary construction stage analysis. Based on the analysis, the measurement during construction was planned. Several sensors and measurement devices were installed at appropriate locations. During the whole launching stages, the measurement was performed and the corresponding data were monitored and stored in real time. The comparison of the responses from the analysis and the measurement showed no indication of yielding of the structural members. Consequently, the construction of Nakdong bridge was concluded to be relevant.
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The subway concrete box structure can`t establish expansion joint because of animal power delivery of the subway rail. In this case, As increase of structure volume, it is subjected to cause temperature crack. The temperature crack due to the heat of hydration classified a nonstructural crack. but it has a bad effect on durability of concrete structures. especially, in case of a subway concrete box structure, when a water-proof facilities is beaked on an outer-wall, the water leakage occurs through a penetration crack generated from a wall of the concrete structure too. This paper, for the subway concrete box structure, examined a condition of temperature crack occurrence by a heat of hydration concerned external temperature from analysing by a three dimensional finite element method.
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This paper presents the methods which estimate the influence of ground subsidence and the stability of buildings by tunnel excavation in urban area. First, we study the behaviour of ground subsidence using neural network and numerical method. And we analyze the characteristic of both methods. Using the both methods, we evaluate the stability of buildings by subway tunnel excavation and we compare the results of the neural network and numerical analysis.
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Greater expansion and more frequent operation of the railroad transportation system anticipated due to its characteristics including low cost, safety and mass transportation. Recently, effects on the railway structures due to expansion of newly constructed road, construction of subway, city gas pipeline, communication network, electric power network and construction of other railway underground crossing in accordance with urban planning and organization has influenced safe operation of trains. Accordingly, standard for selection of construction method that will enable construction of more economical and rational subway underground crossing structures by preventing problems occurring at the time of above construction works and accidents in safe operation of trains due to construction in advance is definitively necessary. Although there are numerous construction methods that can be applied at the time of construction of railway underground crossing, there are much difficulties in selection of appropriate construction method that considers characteristics of each construction method on non-excavation type construction method, train operation plan of number of operational routes and on-site circumstances. Therefore, this research aims to present rational standard for selection of construction method for such, and standard for slowdown speed and interception of train when passing the areas of slowdown in sectors under construction.
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Onboard ATC performs the train speed ristriction function by receiving the speed limit on sections of track from wayside ATC. Onboard ATC can protect passenger from collision and derailment, and so on. So, the high level of safety and reliability for Onboard ATC is required, and by this reason, it is also required to improve the safety of Onboard ATC by applying the result of safety analysis on the Onboard ATC into its design and developing from the concept definition to the detailed desing phase. The paper introduces, when developing Onboard ATC, the safety improvement of Onboard ATC can be accomplished by applying system requirements from Risk Analysis into software and hardware.
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Several cases of foreign to basis much researches for old line speed elevation of internal railroad consist. Examine about improvement and development of consisting signal system in internal. Examine about establishment of suitable examination and formality creation for road test and road test plan in domestic environment. Effective application of skill development work and examination for technique security and road test planning should be established. Studied about examination of internal old line speed elevation business and road test direction that progress current.
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In the past decades, complain about ground vibration and noise induced by pile driving has been quickly increased. Because of that, auger The role of train has expanded as mass transportation according to the increase of train passenger. The train operation personnel are more emphasis on the safety of train operation due to the increase of train's role. The reason is that the train transports many people daily. So, if there is natural disaster, such as earthquake, flood, high temperature, and so on, it will become disaster. Therefore, this paper introduces and proposes wayside detection system, which can be helpful for the safety assurance of train operation.
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도시 대중교통을 주도하는 도시철도에서의 중요한 기능인 신호 연동장치의 주요 논리 회로 중 가장 취약한 3, 4호선의 소형 (Non-Vital) 계전기를 성능이 향상된 전자연동장치(PLC)로 개량함으로서 사전 장애 발생요인을 제거, 열차 안전운행 확보는 물론 설비의 현대화로 업무 향상에 기여하고 신호설비 유지 보수의 합리화 및 효율화를 기할 수 있도록 신호설비의 기능개선 및 발전 방안이 되도록 하였다. 특히 고장 발생 빈도를 낮추기 위한 방안과 설비 보완 및 신설 등 종합적이고 실현 가능한 설비를 구현하고자 하였으며, 기존의 노후된 신호시설이나 교체 예정인 신호 설비들을 효율적으로 개량하기 위한 방안으로 신호 관련기술기준과 표준을 바탕으로 신호시스템의 합리적 발전에 일익을 담당코자 하였다.
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Communications Based Train Control(CBTC) is a continuous, automatic train control system utilizing high-resolution, train location determination independent of track circuits; continuous, high capacity, bi-directional train-to-wayside data communications; and trainborne and wayside processors capable of implementing vital functions. In this paper, we present a basic design of CBTC system based on ERTMS/ETCS specifications. The basic design is composed of system requirements analysis, system functional analysis, system architectural design, sub-system requirements analysis, sub-system functional analysis. Each deliverable has been produced according to a development process based on UML/SysML.
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Bimodal Tram is the newly developed vehicle for both the tracked way and the public road. Its operation system has some characteristics including BIS(bus information system)/BMS(bus management system) based on ITS(intelligent Transportation system) which is used presently in public transportation operation system. One of them is more accurate vehicle fleet control based on both magnetic maker position reference system and GPS(global positioning system) and the other is automatic vehicle control for emergency situations by the Bimodal Tram operation system which will be performed by the unified control and operation center. This paper has investigated the requirements and functional definitions necessary to construct the unified control and operation center for Bimodal Tram operation system which will be more efficient and secure public transportation system than the conventional ones.
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Computers are increasingly being introduced into safety and reliability critical systems. The safe and reliable operation of these systems cannot be taken for granted. Malfunctions of these systems can have potentially catastrophic consequences and they have already been involved in serious accidents. Software fault prevention, fault tolerance, fault removal and fault forecasting are the techniques to be used, implemented and verified for embedded software in critical systems as the contributors to safety and reliability of the software. To use them when developing a software product, a relationship must be established between them and the development processes, the methods and techniques to be used to develop software, as well as with the different product architectures. Railroad signaling system software is a safety-critical embedded software with realtime and high reliability requirements. The primary purpose of the safety management is to prevent the loss of lives or physical damages arising from potential hazards in the railroad signaling system. This study provides a systematic approach to analysis of potential hazards for their management during the system life cycle to assure the identification and definition of the most appropriate hazards.
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Although the up-to-date(high) technique is developing and automating in many fields, the center of the all fields is closely connected with the human resource. Also, the railway driver is required to have both high technique and high level of mental work. Therefore, this research will grasp the types of the railway driver groups through railway driver's task stress analyze(JCQ and Job Content Questionnaire), and then analyze the human errors which the types can occur. Finally, this research will propose the way to reduce the human errors.
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Since the railroad accidents due to the human error occupy considerable proportion among the railroad accidents, it is necessary to study the propriety of the physical examination system for the railroad workers. Our government is promoting some systematic supplementation for railroad safety on the basis of the Railroad Safety Act. In this paper, we perform a comparative analysis of domestic and foreign physical examination systems for railroad workers. We also compare the physical examination system for public officials with that for railroad workers. Then we consult expert opinions of the Korean Society of Occupational and Environmental Medicine. Through the comparative analysis, we provide useful information that is needed to amend the physical examination system.
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철도수송현장에는 인적오류에 의한 사고가 대부분이며 그중 직접 열차를 조종하는 기관사의 신호 확인 결여, 제동취급 불량, 억측운전, 타성에 젖은 불안전한 습관 등이 사고의 원인되어 사고가 발생되며 판단과 조치미숙으로 병발사고로 이어진다. 우리는 10년간 운전사고 통계분석으로 사고유형과 발생 비율을 조사하고 철도원들의 인적오류로 인한 국내외 사례를 분석하고 대구지하철 화재사고와 서울도시철도 7호선 화재사고를 비교분석을 하며 일반철도와 지하철 1인 승무로 인한 문제점을 찾고자 한다. 또 철도사고를 방지하기 위해서는 이론과 기능이 겸비된 우수한 인력을 양성해야 하는 가운데 철도기관사 양성 시스템과 다른 나라 양성제도와 법과 규정을 비교하고 사상사고로 인한 직업병과 그 대책을 찾기로 한다. 결론으로 사고원인은 인간에게 있으며 교육 및 인사시스템에 많은 문제점이 발견되어 직군과 직렬의 개방이 필요하며 다양한 인적자원을 적의적소에 배치하여 1차적 인적오류를 차단하고 직업병 발병과 처리를 조기에 해결할 수 있으며 철도 접근성이 없는 일반인 공채보다 직원가운데 기관사를 양성하는 교육시스템 전환과 지하철 열차화재나 차량고장사고로 처리를 위해 선진국처럼 2인 승무를 대체할 제도적 법제화와 1인 2기 인사시스템 개선이 필요하다.
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It is recommended that reasonable and well-organized standards of the locomotive's requalification system, as it stands, should be established through comparing with foreign of the country for verifying it's propriety. The purpose of this study is to develop the process of locomotive's requalification system for reducing human errors which has been founded as important cause in railway accidents and safety. Therefore, some effective alternatives suggested in this study may be used as basic data for supporting the Korean railway safety law.
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In this paper we introduce the Failure Management System for AREX's Signalling System which is applied by RAMS management. The corrective action report is classified into 3 group, scheduled maintenance, non-scheduled maintenance and the reported failure maintenance. The scheduled maintenance is for the failure detected by periodic inspection and it is concerned as the Preventive Maintenance. The reported failure maintenance is for the failure reported by non-maintenance staff and non-scheduled maintenance includes all corrective action except the works of the previous 2 group. RAMS analysis is based on the FRACAS data connected with the corrective action reports. AREX computerize the all process by the Facility Management System of Integrated Information System.
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The importance of reliability and safety, recently, shows a tendency to increases in railway system constructions and projects. At the point of view of safety, especially, the railway authority proposes an establishment of the safety case that is the documented demonstration that products comply with the specific safety requirements in railway industry. In case of reliability activities, there is no systematic documented demonstration in the railway industry. At this circumstance, this study presents the establishment of Reliability, Availability and Maintainability Case for railway system based on the MoD(Ministry of Defence) 00-42. This RAM Case will support that systems and products produced from suppliers or manufacturers meet the specific RAM requirements during the system life cycle(i.e, from design to operation & maintenance) through systematic process and evidences. Also, it is expected that railway system operations will be managed and supported from reliability activities in accordance with RAM Case.
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This Paper introduced a proper time evaluation for railway emergency response staffs using the Therblig Analysis. We defines what Activities the emergency response staffs should take when the fire occurs on the railway. This has been possible through the development of the scenario that is focused on the fire accident and it also has been driven to minimize the spread and damage of the accident. Gilbreth's Therblig Analysis has been used here to derive the reasonable time that would take for the emergency response staffs to respond to the fire accident on the railway system. We developed Emergency Response Scenario against Accidents and defined the Activity of the main Action for Emergency Response staffs.
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The purpose of this paper is to analyze cost-effectiveness of a train simulators. The cost-effectiveness of training program is assessed by multiplying transfer effectiveness ration(TER) by training cost ration(TCR). If their product is less than one, the program is not cost effective. Even if a program is not cost effective, however, safety considerations may be important to consider.
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In this study proposes training & education improvement of domestic railway by intensively benchmarking MIL-STD training & education manual. Through this MIL-STD-1397D & Railway Safety Good Practice in Training, we composed 3 steps of training & education, that proposes to specific process.
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This paper is described the System of effective RAMS Management established for AREX Railway System. This system for AREX's E&M system contains FRACAS(Failure Reporting, Analysis and Corrective Action Plan) and computation of RAMS indices. This procedure is applying to improve the Reliability, Availability, Maintainability and Safety for railway system in operation stage. Furthermore, this system would be a basis of RCM(Reliability Centred Maintenance).
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Recently the assurance of railroad safety is very important issue in KOREA because there are lots of changes in the railroad industries. The Railway Safety Act was established in order to cope with these changes effectively and prevent the railroad transportation accidents. According to this law, Korea Transportation Safety Authority (KOTSA) has been entrusted with 'Integrated Railroad Safety Audit (IRSA)' and has implemented the safety audit to the railroad operation agencies such as Korea Railroad (KORAIL) and the railroad facility management organization such as the Korea Rail Network Authority (KR Network). The target of IRSA is to establish the effective rail safety management system and to raise the safety level of the railroad operation and facility agencies by checking synthetically their performance of safety duties with sincerity according to the Railway Safety Act. The purpose of this paper is to improve the efficiency of IRSA by the comparative research between IRSA and other similar safety audit system. To study the efficiency of IRSA, we investigated the rail safety audit systems of EU system specially France, England where the big changes have happened for the rail operation concepts and Japan where government entity control the railroad safety. The international standards of Occupational Health & Safety Assessment Series (OHSAS 18001), Quality Management System (ISO 9001) and Guidelines for Quality and/or Environmental Management Systems Auditing (ISO 19011) are investigated.
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Urban transit is a large scale complex system which combines rolling stocks, power supply, signal communications, tracks & stations. Therefore standardization is very important because it is difficult to find causes when failures or accidents occur. The standardization of urban transit increases safety and economical efficiency, and also gives passengers convenient and comfortable feeling. We, Korea Railroad Research Institute(KRRI), had finished the 1st phase study of urban transit standardization from '95 to '06. And 2nd phase study on rolling stock, information & communication, subway station has been performed from July '07. In this paper, we introduce what we study on urban transits standardization during coming 5 years. We expect our study will contribute to increase the efficiency of urban transit.
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고속철도 정차역은 시설현황, 정차역의 위치, 주변 토지이용 등 역세권 주변의 개발 정도에 따라 정차역에서 유발 및 유입되는 통행량에 큰 차이를 보이게 되며, 역과 역세권이 잘 발달된 정차역은 유동인구가 상당히 많음에 따라 특별구역(시설물)으로 정의되어질 수 있다. 이러한 특별구역은 많은 통행량을 발생시키는 토지이용 구역으로서 대학교, 공항, 대형쇼핑몰 등이 해당되어 왔으며 고속철도의 이용자가 증가함에 따라 정차역이 지역 내 통행수요에 미치는 영향을 고려하였을 때 특별구역으로 정의 될 필요가 있다. 지역내 교통처리 계획 및 연계교통계획 수립을 위해 특별구역에 대한 통행수요추정은 예전부터 상당한 관심이 요구되어 왔다. 그러나 전통적인 4단계 모형의 통행발생 및 분포 모형으로는 이러한 특별구역의 통행수요를 예측하는데 한계가 있으므로 개인별 통행행태를 고려할 수 있는 새로운 분석방법인 활동기반모형(Activity-Based Travel Demand Model)의 적용이 필요하다. 이에 본 연구에서는 고속철도 정차 역의 교통수요추정을 위해 활동기반 모형의 적용방안에 대하여 소개하며 향후, 적용가능성에 대하여 제시하도록 한다.
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Recently, with increasing interested in improvement of operational reliability and the systematic maintenance activities, the RCM analysis has been applied and tried to lots of applicable industries. This study covers applying the probability of failure cause to FMEA, and proposes an analytical method for this. Also, the measures of quantitative classification for the result of failure cause probability are addressed. Based on the field data, this thesis presents an identification for causes and characteristics of failure, and reviews them periodically from the above methodologies. As using FMEA applied the probability of failure cause, we in the future can look forward to improvement of efficiency for failure diagnosis & inspection, and reliability.
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Revenue management is a new approach method to solve the problem of supply and demand, and one of fields which is diffused quickly at the service enterprise to use perishable-asset like the transportation business. It is based on multiple fare policy that discount charge reservation should be received if the benefit value of current discount fare is more than expected profit of the normal fare reservation it will be able to occur in future when suitable goods is sold to the customers at discount fare, at the time they want, and at assigned seat by controlling supply and demand from market. In this research, I will review on initial operation case for special class goods that the seat which is limited is assigned at some of train and portion of KTX for demand dispersion and new demand creation at peak time, put a limit in purchase conditions, and provides discounted fare. I will also try to find implication for strategic operation.
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Korean railroad has been accomplished the structural change through separating of facilities and operation of railroad in 2004. The existent government organization was transformed into the public, this caused problem of renovation of railroad management. Korean railroad has been the integrated management of passenger and freight. As putting the passenger service as a priority, freight transportation have fallen behind and not attained good sales results. Restructuring in Korean railroad would bring about considerable improvement, but still not come out of the deficit operation. To find a way out of this situation, there needs to make renovation and extend new enterprise. However, to operate the railway freight transportation more competitively, make up situation that can possess competitive power fundamentally. From this perspective, the purpose of this study is to analyze the necessity for separated operation of passenger and freight railway transportation. By doing this can expect to obtain the competition power of railway freight transportation, and is a help to build up the independent management system of railway freight transportation and secure competitive high position about other transportation systems especially road.
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With the advent of 21st century, the economic and cultural value of the tourism became more important than ever. And many countries have been aware of the importance of it and trying to promote it. In the railway industry, the sightseeing train is the most crucial element. It can be used as a means of transportation for the tourism or can be the objective of the tourism itself. The sightseeing train can contribute to improve the level of the national leisure life, to fill the cultural gap among the regions, to make foreign exchanges, or to accelerate cultural exchanges among countries. So, I would like to present some guidelines on the development of the sightseeing train through the research on the sorts, the designs and the services of the sightseeing trains operated in Korea or other countries.
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Life cycle costing is one of the most effective cost approaches when we choose a solution from series of alternative so the least long-term cost ownership is achieved. Life cycle costing in railway industry has been focused on the prediction of investment for railway vehicles. But in today, the life cycle cost, LCC, prediction on the aspect of operation and maintenance cost through whole life cycle is highly necessary. In this paper, we present a strategy for the development of life cycle cost estimation software on the aspect of maintenance strategies of railway vehicle. For this purpose, we suggested a structure of LCC software based on the UNIFE LCC model. And we developed a pilot version of software to evaluate the LCC model that we suggested for railway vehicle. We performed LCC analysis on the brake module of metro vehicle in case study and concluded that the software and model developed in this research could enough to support engineers in choosing better cost effective solutions from many alternatives.
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Most operational organization and railway authority which conduct scheduled maintenance(SM) have carried out the preventive maintenance(PM) based on the information provided from supplier and manufacturer of railway system. However these activities are far away from reality and low the efficiency, it is because an appropriate methods for system selection didn't take into account for improving maintenance efficiency. Therefore, the current SM tasks and maintenance activities lead to lots of spend on the cost and time. To solve the above problem, this thesis presents new approach methodology. This proposes the criteria for reliability centered maintenance(RCM) system selection through level of quantification of each parameter, i.e, frequency, severity and maintenance cost, etc. To do this, the field operation data and information of maintenance cost are essential. As applying this methodology, we can look forward to improving efficiency of PM/SM, and reducing cost.
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The annual power cost for Seoul metro operations is about 65.5 billion won, of which rail motors account for 60% among total power consumptions. It is expected that the power consumption would increase because of global warming, future high electric equipments demands, etc. To reduce these consumptions, it is necessary to analyze the transportation demands of passengers, arrange the power-saving driving environments, respond flexible vehicles service, and improve how to drive vehicles. These method to reduce power consumption for rail motors can lead to improve the Seoul metro management. In this research, the improvement plan is derived by collecting and analyzing the data for total 33 power consumptions factors, screening top 10 factors by priority and impact, establishing each hypothesis to execute correlation and recursion analyses. As a result of 4 items research among top 10 affected factors, the power consumption for rail motors in 2006 is effectively reduced; the power usage is down with 13,870 kwh, from 531,539 kwh to 517,669 kwh, and the cost is down with 1,026 million won, from 39, 334 million won to 38,308 million won.
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Rotem Company has designed and manufactured bogie for Diesel Multiple Unit (DMU) according to the European standard UIC615-4, which si normally used for designing bogie frame. Because the countries located in Middle East do not have their own regulations for bogie design, most of running bogies in Middle East are designed by using European standard UIC615-4. UIC615-4 specifies the loads that bogie frame should withstand, indicates the way of material data to be used and the principles to be during verification by analysis and test. The bogie frame depends on the load conditions and magnitudes which are subjected to during service and characteristics of materials they are manufactured from. From the above reason, Rotem Company has performed Finite Element Analysis and load tests on the bogie frame according to UIC615-4. This research contains the results obtained by the analysis and the load tests. Also, this research verifies that the bogie frame has a static strength and fatigue strength. The analysis is carried out using I-DEAS 12 NX Series and specially designed test jigs and equipment are used for the load tests.
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The floor structure of railway vehicles consists of plywood, rubber, and wood keystone plate which affects on the comfort of passengers. Its structural characteristics has been investigated experimentally and numerically for samples of beam and plate structure, and the real floor structure in this paper. The material properties of etch part measured directly by experiments. The deformation and stress distribution of the sample beams for 6 different joints were sought experimentally and calculated using a commercial software. The numerical calculation shows that the effect of friction and clearance between joints is crucial. The DMU/EMU plates were also experimented and compared for different loading conditions. The structural characteristics of the whole floor structure were calculated numerically. The results show that the method of joint between plywoods is an important factor to decide the strength of the floor structure of railway vehicles.
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As the South Korean rolling stock industry is developing designs for full compliance with the European Standards, it is fitting to take a look at these two core standards. The paper presents an overview of the load cases and structural requirements developed in Europe for the design of safe and compatible rolling stock vehicles. These load cases and structural requirements have been compiled into two standards namely EN12663 and EN15227. Standard EN12663 was developed as a reference design requirements standard. The work was mandated and sponsored by the European Committee for Standardization and Standard issuing National Institutions. EN12663 specifies a series of proof and fatigue load cases for European rolling stock regulations compliant vehicle designs. As EN12663 does not address the crashworthiness issue, a dedicated crashworthiness standard, EN15227, was therefore developed in a similar manner through industry wide consultations managed by a Trans-European working group of experienced engineers and specialists. In both standards, the vehicle and/or trains are grouped into categories reflecting the vehicle types and/or their indented operational function. EN15227, developed to complement EN12663, addresses the "passive" crashworthiness capability of the vehicles and trains. EN15227 specifies reference crash scenarios similar to those found in the Technical Specification for Interoperability (TSI) of high speed trains operating in Europe. The overview also touches on a general comparison with the corresponding British Group Standard (GM/RT2100) and also the UIC leaflet based load cases. The exercise is extended to pertinent design load cases specified by the Federal Railroad Administration (FRA) in the US.
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Mechanical and thermal analysis properties of carbon fiber/epoxy composite for train carbody were evaluated by varying with environmental factors such as ultraviolet, temperature, and moisture. Accelerated environmental aging tester was utilized for this study. Testing temperature was set to
$80^{\circ}C$ and ultraviolet was obtained through xenon-arc lamp. To consider moisture, water sprayed on specimen for 18 minutes every 2 hour. All the specimens were made of CF1263/Epoxy composite. Mechanical properties such as tensile, bending, and shear properties were evaluated through a material testing system. Also, thermal analysis properties such as storage shear modulus, loss shear modulus, and tan${\delta}$ were measured through dynamic mechanical analyzer. Finally surfaces of the composite exposed to environmental factors were examined using a scanning electron microscope. From experimental results, those properties of CF1263/Epoxy composite were shown to be slightly decreased due to environmental factors. -
In this paper, stress analyses using shell and solid elements on weld zone of railway bogie frame were performed. To calculate stress distribution on weld zone, a coupling model using shell and solid elements was suggested. For this purpose, we performed specimen analyses on T-type solid and shell model of T-type panels which were modeled using shell elements, solid elements and coupled elements, respectively. The result showed that the stress concentration at weld zone was occurred in solid model, but it didn't occur in shell model. And the stress distribution of coupled model was similar to that of solid model. Also, we applied the coupled modeling method on the analysis on weld zone of bogie frame. The stress distribution of coupled model showed much higher compared to that of shell only model. Therefore, the coupled model method is highly recommended for the stress analysis in weld zone of bogie frame.
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Recently it is a tendency that Diesel rolling stock is committing in the commuter's train route of the suburb for solving commuting traffic congestion. It has advantage which expense of diesel rolling stock is relatively cheaper than electric rail car or high-speed train. In addition, it can be using the exist route without large-scale facility investment. Because of this advantage, the demand of diesel rolling stock occupy regular portion from overseas railway car market. GM/RT 2100 specifies the loads vehicle bodies shall be capable of withstanding, identifies how material data shall be used and presents the principles to be used for design verification by analysis. Therefore, in order to fulfill the structural requirements, Rotem Company has carried out Finite Element Analysis (FEA) to verify whether the carbody structure has enough strength to withstand the loads specified by GM/RT 2100. This research contains the results obtained by the analysis. The analysis was carried out using I-DEAS 12 NX Series
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It is known that bogie frame must have sufficient stiffness for car body and passenger weight and transfer traction and braking force, and as of today most studies and verifications are restricted to static and fatigue analysis for force acted on bogie frame. Bogie frame is mounted with equipments to control the signal, traction and so on, this equipment's behavior is subjected to vibration mode occurs on running condition. If the resonance occurs on this equipment, the possibility of crack occurrence on bracket connected with equipment and bogie frame will be increased. In this paper, the method of vibration strength verification for bracket attached on bogie frame will be introduced by using frequency response method.
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The durability of carbon/epoxy composites under salt water environment was investigated through salt water spray tester. Salt water environment was obtained through salt spray and salt immersion. 5% NaCl solution was used for salt water as natural salt water. Mechanical test was performed to obtain tensile properties, flexural properties, and shear properties of carbon/epoxy composite over 12 months under salt water environment. Dynamic mechanical analyzer was used to investigate thermal analysis properties such storage modulus, loss modulus, and tan
${\delta}$ . Also FT/IR test was conducted to investigate a change in chemical structure. According to the results, mechanical properties were found to be slowly degraded as a function of exposure times. Regarding to thermal analysis properties, storage modulus was insensitive to exposure times, but loss modulus was shown to be slightly decreased. Although the shape and location of peak in FT/IR were not much changed, the intensity of peak in FT/IR was affected on exposure times. We also found that salt water immersion was more severe to the durability of carbon/epoxy composite rather than salt water spray. -
The rolling stock which is used the most frequently by public transportation has to secure reliability and safety. In these, vibration is the important factor which causes of serious problem of rolling stock. By the way, rolling stocks vibration test specific activity that is using translating JIS standard is serious mistake, but it is actuality that is used until present more than ten years. Study wishes to analyze problem of standard of domestic rolling stocks and present countermeasure.
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The levitation system of Maglev is composed with electro-magnet, power supplier, controller and sensor. The complex interactions between above subcomponents define the characteristics of electromagnetic suspension of the vehicle. In this study, to understand the influence of controller on the running performance of Maglev, the new controller based on LQ theory will be designed and be simulated with simplified vehicle model. Then the influence of controller on the characteristics of electromagnetic suspension will be reviewed through comparison with existing control algorithm of our prototype vehicle.
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전동차 자동검사 장치의 하나인 판타그라프 습판마모 자동측정 시스템은 첨단 기술인 머신비젼 기법을 이용하여 습판체의 마모상태를 검수자의 육안검사 없이 마모량과 교체시점 등을 판단하는 시스템이다. 본 논문에서는 우천시 빗물로 인한 노이즈(Noise)가 영상에 입력되어 판타그라프 습판의 에지(Edge)를 검출하는데 영향을 미쳐 신뢰성을 저하시키는 요인이 된다. 이러한 노이즈 제거를 위해 평활화(Smoothing) 처리로서 필터링 기법을 적용한 평균 마스크(Averaging mask), 중간값 필터(Median filter) 기법을 사용하여 문제점 등을 확인하고, 머신비젼 기술에서 사용되는 영상측정에 있어 에지 추출(Edge Detection)이 노이즈의 영향을 받지 않고 안정된 결과를 획득할 수 있도록 유도하고자 한다.
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The KTX train which brings April 2004 high-speed railroad commerce operation time is operated currently Kyungbu line Seoul-Gwangmyeong-Daejeon-Dongdaegu-Pusan and Honam line Youngsan-Gwangmyeong-Seodaejeon-Kwangju/Mokpo. The high-speed railroad opening to traffic after KTX train interior noise follows in railway line quality change and it is changing together. From the research which it sees until opening to traffic after present time of the KTX vehicle it executed an interior noise quality change from Kyungbu line.
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Faults of rotating parts of a train normally generate unexpected frequency band or impulsive sound[1] which has a period when it moves with a constant speed. The former can be detected by the moving frame acoustic holography method, which visualizes sound field that is generated by a moving and emitting pure tone or band limited noise source. We have attempted to apply the method to the latter case: the periodic impulsive sound which generate different signal compared with what can be measured by the band limited noise. The signal to noise ratio which determines the success of early fault detection must also be studied with the impulsive and moving signal. This research shows how the problems related with these issues can be resolved. The main idea is that periodic impulsive signal can be expressed by infinite set of discrete pure tones. This enables us to obtain lots of holograms that visualize periodic impulsive sound field including noise by using the moving frame acoustic holography method. Therefore holograms can be averaged to improve the signal to noise ratio until having reliable information that exhibits where the impulsive sources are. Theory and experiment by using the miniature vehicle are described [Work supported by BK21 & KRRI].
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In this paper, the possibility of time reversal phenomenon was investigated in damage detection of structure. In conventional lamb wave techniques, damage is identified by comparing the measured data (baseline signals) and the current data. But this method can lead to high false signal in the intact condition of structures due to environmental conditions of the structures. So in this studying, we investigate the possibility of damage detection in the aluminum plate using the time reversal phenomenon of lamb waves.
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Electromagnetic suspension, the suspension system used for Maglev trains, is now being applied to urban and inter-city transportation systems, offering environmental benefits. This suspension system is actively controlled to stabilize the suspended vehicle as it runs over an elevated guideway, which, for various reasons, may have deviations in its height. For this reason, frequency responses of the suspension to height deviations must be predicted in the system design cycle. The equations of motion of the electromagnetic suspension employing the 5 state feedback control law are derived for frequency analysis. The results of this paper could be used to determine design requirements for the urban Maglev transportation system currently under development in Korea.
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In this paper, the vibration of a rotating shaft with a thin rigid disk is considered. It is assumed that the shaft has uniform, circular cross-section. Based on the Timoshenko-beam theory, the transverse displacements and slops in two lateral directions, the axial displacement, and the torsional deformation are considered. A spectral element model is developed by using the variation method for the vibration analysis of the rotating shaft with a thin rigid disk, which is modeled by two shaft elements and a thin rigid disk element. The result of vibration analysis by finite element method is compared to the result of this research.
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This paper concerns dynamics of a wheel-axle set on a tangent track which was already published in a book titled "Dynamics of Railway Vehicle Systems" authored by Garg and Dukkipati [1], pointing out several missing terms and erroneous parts in the derived expressions on the conventional governing equations of motion. It is indicated that the x-direction components of normal forces at left and right wheel-rail contact points in the equilibrium axis were missed. Another point is that in deriving the creepages the disturbed velocity components in both x and y directions in the equilibrium axis should not be disregarded in the first term of the numerators. When considering the creepage in the y direction in the body coordinate system, the second term of lateral velocity at the contact point also cannot be neglected. Besides, the hyper-assumptions in the final expressions of vertical components of normal forces at left and right wheel-rail contact points have been recovered in reaching the final stage of analytical model development. Finally it is noteworthy that the process of applying creep theory is deemed to contain a little bit inconsistencies and ambiguities to be clear.
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It is found that there are many serious errors in deriving the existing governing equations of motion for a wheel-axle set negotiating an arbitrarily changing radius curve by Vijay K. Garg and Rao V. Dukkipati. Among other things, despite the hypothesis on arbitrarily changing radius of curve, there had been no taking a time derivative of the radius R in the first half of the derivation. Even if the D'lambert force arising from the centrifugal acceleration of vehicle body or bogie was appropriately taken into account while calculating cant deficiency, it is unnecessarily duplicated in the force vectors of governing equations. The graphical model given in Fig. 5.15 is not enough to follow those developed expressions from both physical and structural points of view. Besides, there are some blunders in assigning plus or minus sign not to be regarded as simple typographic ones and similar mistakes are committed in deriving creep force expressions as in the case of a wheel-axle set on a tangent track.
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To assess the derailment safety of the Samaeul Train, We developed a fleet analysis model and carried out sensitivity analysis of the variables related to derailment factors with ADAMS/Rail computing analysis method. Depending on the variation of the running speed in curve section, derailment coefficient and wheel load reduction rate are high at right side wheels in slow running speed section and low at left side wheel in high running speed. According to decreasing the radius of curve, derailment coefficient and wheel load decreasing rate are increased. Derailment coefficient is proportional to transition curve length and wheel load decreasing rate is constant. Cant value rising causes wheel load deduction rate rising.
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In this study, it is offering a numerical method which assesses running safety of the freight car loaded CWR when passing through on the conventional railway by additional lateral load. It is suggested based on the numerical reviews of the safety against derailment after seeking the derailment coefficient estimated by wheel load-lateral force equation in the section that curve radius is small
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Two major parameters, i.e. carbon dioxide (
$CO_2$ ) and particulate matters smaller than$10{\mu}m\;(PM_{10})$ , were selected as the index pollutants in managing indoor air quality. The former pollutant,$CO_2$ , is the index that shows the ventilation status and is exhaled by passengers when they breathe in train or subway. It is generally known that high$CO_2$ concentration in the vehicle may be decreased by insufficient air-tightening vehicle bodies and the air is ventilated when vehicles stop at the station and doors open. However, there is no established proof or quantitatively identified data on how much the$CO_2$ concentration is reduced when ventilation is done while doors are opened. In this study,$CO_2$ concentrations were measured in 6 lines of Korail and one line of Seoul Metro subway linesand a theoretical approach was takento predict the changing trend of$CO_2$ concentrations during the operation of vehicle by using$CO_2$ dilution factor through natural ventilation. As a result, the change could be quantified and it was found that app. 35% of indoor$CO_2$ was removed through natural ventilation. -
There have been worldwide efforts to develop environmental-friendly transportation systems, which aim to solve the environmental issues such as pollution with the traffic congestion in downtown. For some developed countries, environmental indicators to estimate their environmental performances as well as eco-design technologies in the field of transportation have been already secured. In Korea, however, relatively fundamental studies which are insufficient to calculate quantitatively the environmental impacts have been performed. In this study, the life cycle assessment was introduced as one of methodologies to evaluate environmental performance and reduce environmental impacts of a bimodal tram system throughout its entire life cycle, including design, manufacture, operation and disuse steps.
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Seoul Metro has operated the air cooling equipment established in a machine room of a station building to improve our services focused on our customers who use Seoul Metro during the summer season. However, a new set of problems has arisen with the cooling tower to support a heat exchange of cooling water. One of them is loss of efficiency in the air conditioner. The leading cause of this problem is that we use an underground type of the cooling tower. As the machine room of a station building is located in the underground of inner city because of the nature of the subway, it is difficult to establish the cooling tower on the ground. The underground structure of the No.
$1{\sim}4$ subway line is unsuitable for the location requirements of the underground type of the one because it has a limited space to set up the air cooling equipment, for example, the cooling tower and a ventilating opening. As a result of such an unfavorable condition, the cooling tower doesn't work efficiently and the warmth of cooling water because of insufficiency of a heat exchange and a refrigerator's technical obstacle such as a high-temperature and a high-pressure has arisen. Accordingly, the efficiency of the air conditioning is getting lower and lower. Another problem is too wasteful with water. Each station uses the water over 30 tons every day with waterworks to replenish the cooling tower such as a evaporation, a scattering and a distribution of water. Nevertheless, the more an air conditioner increase, the more the use of water supply increase. For this reason, we can't help wasting an enormous amount of water and discharging the congelation of a low temperature(about$15^{\circ}C$ ) occurred in a heat exchanger inside an air conditioner. The purpose of this study is to analyze the utility of congealing water to improve efficiency of the air cooling equipment and save energy as a supplementary water for the cooling tower. -
The input data for the interior material of the train is one of the key points for enhancing the accuracy of fire simulation. In this study, we investigated the Fire Test Methods for the Fire Dynamic Simulator modeling for railroad passenger trains. We should get the thermal inputs such as ignition temperature, conductivity, specific heat, vaporization heat, effective heat release. With the simple conduction model for cone-calorimeter test, they could get more than HRR. Kinds of methodology were introduced for better thermal data for real material.
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It was intended in this study to seek for the measures to utilize the USN technique, which has high usability due to low price and low power consumption, in air quality monitoring. As a method, the sensors of temperature, humidity, particulate matters (PM10), and carbon dioxide (
$CO_2$ ) were installed in the self-manufactured sensor nodes; the nodes were installed in the waiting rooms and platforms of a subway station and the measurements were collected at real time with use of a computer which micro gateway was built in. Collected data was to be processed by the statistics program installed in the computer; the collected data is to be used in managing the air quality of stations after transmission to the ventilation system of ventilation chambers. -
The particulate matters emitted by diesel locomotives cause serious air pollution in stations and railroad. There have been various attempt to reduce the air pollution from diesel bus or trucks. However, the air pollution from the diesel locomotives has been out of control because there has not any adaptable technology. In this study, a diesel particulate filter was developed and applied to the diesel locomotives. A 3,000 horsepower large-scale locomotive and a 1,500 horsepower middle-scale locomotive were used for the test of the filter. The particulate matter emissions before and after the treatment was monitored by a scanning mobility particle sizer and a dust monitor. As a result, it was observed that the particulate matters could be successfully removed from the emission gases by using the filter.
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Thermal cracks are among the key factors that control the quality of a brake disk. Thermal cracks may shorten the lifetime of the disc and increase brake noise. Therefore, high heat-resistant brake disk materials are needed. In this study, three kinds of disk material were tested. They are composed of C, Si, Mn, P, S, Cu, Cr, Mo, and Ni. For the three materials, tensile tests, hardness measurement, metallurgical structure analysis, image analyzer analysis, etc were carried out. And friction tests were performed by a small scale dynamometer.
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The brake system of train must posses the large braking effort in order to stop the train safely within the limited traveling distance. But, the excessive braking effort has been deteriorated the ride comfort due to high level of deceleration and jerk, and sometimes occurred the skid, because the applied braking force exceeds the allowable adhesive force. This skid causes not only to increase the stopping distance but also to deteriorate the safety of train and damage the rail surface by wheel flat. In the present paper, the braking force for disc brake of Korea High Speed Train (HSR350x) was measured through on-line test and the adhesion force was estimated by using the analytic model in the skid condition. Also, we have discussed the relationship between the actual disc brake force and the adhesion force in real skid condition.
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To reduce the cost and the time of transport in Eurasian railroad networks such as TKR(Trans-Korea Railway), TCR(Trans-China Railway) and TSR(Trans-Siberia Railway) owing to the problem of different track gauges (narrow/standard/broad gauge), it is important to develop the gauge - adjustable wheelset system to adapt easily to these gauges. Moreover, this system accomplishes periodically a conversion operation from the gauge variable segment between different gauge. Gauge adjustable compression coil spring during conversion process accomplishes repetitively a central role for operation mechanism between flange and locking part. Therefore, to assure the safety of the gauge-adjustment wheelset system, it is necessary to stress analysis of the optimized spring in the system. In this study, it was performed to optimal design of the spring for stress analysis by using the genetic algorithm.
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Recently, a double deck train is considered as the one of solutions for efficient and comfortable railroad transportation systems on busy lines without any big investment on existing railroad infra-structures in many countries. However, prior to the operations of double deck trains on existing lines, careful investigations should be performed since the double deck trains have big cross sections, high mass centers and no enough spaces for mounting electric equipments. In this paper, several operational cases of double deck trains in other countries have been reviewed for preparing double deck train operations in Korea.
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We studied on the characteristics of many kinds of tank cars carrying hazard materials and performed structural strength evaluation for tank of asphalt tank car using finite element analysis. We analyzed the tank strength according to JIS E 7102(Design Method for Tanks of Tank Cars). It was found that the maximum stress obtained at the area supported by the saddle is much lower than the yield stress and the criteria of JIS E 7102.
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When vehicles running, vertical force and lateral force act except load of vehicles to rail and wheel. This force happens by complex motion at running. If mark vertical force by P and lateral force by Q, derailment coefficient displays Q/P, most important indicator pointer of running safety judgment. If Q is grown than P from derailment coefficient, than arrived to derailment because wheel climb or jumps over rail. Wheel climb derailment among kind of derailment is when attack angle is +, wheel and rail strike and flange rides to rail. This derailment occurs much in curved line and occurs in low speed. In this study, occurred when running at low speed on curved line, analyze cause of derailment and presented the countermeasure plan.
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In this paper, we studied the optimized design of roof structure to be separable roof structure. Also, the design have to satisfy with the GM/RT 2100' missile protection tests to verify the safety of railway vehicle structure. The separable roof structure design could have easier assembly process than whole roof structure in case of the interior outfitting and so on. Optimized design have to have as good as whole roof structure about results from the structure analysis. We studied separable roof structure to be optimized along with GM/RT 2100. The separable roof structure showed that the results have the same level of structure analysis
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Recently, a theoretically-sound design approach, using an elastic multilayer model, is attempted in trackbed designs for the construction of high speed railways and new lines of conventional railways. In the elastic multilayer model, the stress-dependent resilient modulus(
$E_R$ ) is an important input parameter, that is, reflects substructure performance under repeated traffic loading. However, the evaluation method for resilient modulus using repeated loading triaxial test is not fully developed for practical purpose, because of costly equipment and the significantly fluctuated values depending on the testing equipment and laboratory personnel. In this study, the paper will present an indirect method to estimate the resilient modulus using dynamic properties. The resilient modulus of crushed stone, which is the typical material of sub-ballast, was calculated with the measured dynamic properties and the range of stress level of the sub-ballast, and approximated with the power model combined with bulk and deviatoric stresses. The resilient modulus of coarse grained material decreases with increasing deviatoric stress at a confining pressure, and increases with increasing bulk stress. Sandy soil(SM classified from Unified Soil Classification System) of subgrade was also evaluated and best fitted with the power model of deviatoric stress only. -
The objective is to compare with economic evaluation and to analysis the LCC for prestressed concrete used on rail bridge. A new style concrete bridge is difficult to estimate a history for maintenance cost reliably. For the reason, we introduce a analogical interpretation by similar bridge style in order to estimate a appropriate maintenance profile. The proposed method is usefully supplied to estimating the LCC for bridge which is difficult to determine the maintenance cost.
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Internal and external railway management corporations are using the periodic replacement criteria of rail by accumulated passing tonnage and wear to maintain rails for servicing. However, internal the periodic replacement criteria of continuous welded rail(CWR) by accumulated passing tonnage is the one(50kg/m-5 million gross tonnage, 60kg/m-6 million gross tonnage) presented in Japan before. It was estimated with the fatigue life about 50kg N rail joints applied diesel train load but it wasn't applied to current conditions of track; elimination of rail joint, using the concrete slab track and operation of light train load and effect of welding, manufacturing technique, grinding of rail. Therefore, in this study, it was investigated the types of damage and cause in welded rails and examined standards and information resources. Also, this study presents preliminary data to revise the periodic replacement criteria of CWR by current accumulated passing tonnage in bending test of laid welded rail and a survey of track maintenance history of Seoul metro.
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In high-speed line, at some part of the track which rubber ballast-mat installed, track irregularity grew rapidly and affected riding comfort and train running stability. It is urgently requested to establish counter-measures which can be applied to track under operation. To do this, it is very important to analysis the origin of that phenomenon before. Track support stiffness is an essential factor for evaluating track condition. Sudden changes of support stiffness along track occur instability of train and bad riding comfort. Preventing sudden changes of track support stiffness is a key technique in high-speed track maintenance. Besides the sudden changes, the magnitude itself also significantly affects track and train. Low stiffness of ballast-mat makes ballast acceleration area wider. And it may accelerate track irregularity growth. So, the stiffness should be limited. To calculate track stiffness, measuring load and displacement on track is needed. In this study, the behavior of the track which rubber ballast-mat installed was measured and analyzed to understand the origin of rapid growth of it.
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The structural analysis model for estimate of load carrying capacity of railway bridge on service line is important to determine safety of bridges in service, we need to take response of bridge exactly, applying analysis model similar to the real railway bridge most. Track structure which is to distribute loads and decrease vibrations occurred from running train is constructed on the railway bridges. And it is important factor which should be considered to understand exact dynamic and static responses of bridge. But track structure is currently classified as a none structural members in the structural analysis model for estimating load carrying capacity of railway bridge and not considered in analysis model. That's the reason it is difficult to understand exact behavior of bridges. Therefore, the major objective of this study is to develop an analytical track-bridge model which is similar to real railway bridges considering track structure for safety assessment of railway bridge on service line to be effectively done.
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In designing the high-speed railroad track, it is important to utilize appropriate track components to maintain uniform stiffness and ensure track alignment within the tolerance set for that system. In this regard, continuous welded rails (CWRs) were introduced to the Korean railways. Yet the installation of CWRs can result in an adverse impact due to the track/structure interaction on bridge sections yielding variations in the stiffness at the expansion joints. It may also impose additional axial force, generate excessive stress or deflection on track, and loosen the ballast at the ends as a bridge deck contracts or expands owing to a thermally-induced dynamic response. The risk is even greater in a long bridge deck, resulting in track longitudinal irregularities, deteriorating passenger's comfort, and increasing maintenance efforts. This study evaluates the performance of ZLR and their impact on track longitudinal irregularities through the track measuring results on a test section installed the ZLR in order to minimize the thermally-induced responses and the maintenance efforts for the high speed railway bridges.
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3차원 국토환경의 디지털기반의 가시화는 국토계획 및 통신설비계획, 철도건설, 건축, 입체적인 도시공간정보시스템 구현, 안전 및 방재 등에서 많은 필요와 그 중요성이 크게 부각되고 있다. 현재 국가지리정보 사업으로 완성된 2차원적인 지도정보와 시설정보를 3차원의 도시공간으로 재현하기 위하여 기존의 등고선을 이용한 DEM 방식은 많은 한계를 가지고 있으며, 특히, 철도와 같은 노선 폭이 좁고 길이가 길어서 궤적 관리가 어려운 작은 구조물의 경우에는 그 고도모델이 무시되기 쉬우므로, 레이져 측량기술을 이용한 공간대상물에 대한 높은 정확도 취득이 크게 필요한 실정이다. 최근에는 레이져 측량기술과 GPS를 결합한 고밀도 고정도의 높이 값을 얻을 수 있는 LiDAR Data의 획득으로 그러한 한계를 극복하고 있는 추세이다. 비교적 LiDAR 관련 연구가 활발한 해외 선진기술을 연구하고 우리 실정에 적합한 3차원 지형 및 철도시설의 분석이 가능하도록 데이터의 생성기법 및 알고리즘을 개발하여 3차원 공간에서의 최적의 노선관리가 가능하도록 하였다. 이를 위하여 LiDAR Data를 중심으로 하는 높이 값을 DEM으로 변환하고, 디지털 영상의 매칭 및 정확도 평가 등을 통한 벡터와 래스터의 실시간 통합 및 전환으로 장거리 노선에서의 3차원 철도 모델의 생성을 통한 추적관리가 가능하도록 하였다.
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Recently the urban railroad which is under plan and construction in domestic is under consideration Light Rail Transit mostly with the alternative against excess of working expenses of Midium Rail Transit(subway), inefficient transportation problem etc. It come to a conclusion that the application of the light rail transit is proper from reserve feasibility study and approval process of Master plan in Daegu urban railroad Line No.3 Based on hereupon, carried out the detail investigation for optimum system selection which suitable for Daegu urban circumstance in process of master plan can satisfy the working expenses decided in national expenditure support project.
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Recently, the development of the paved track is required as a low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The important factors of paved track are stability and applicability. To be based on this subject, Cement Mortar Pouring(CMP) paved track is developed. CMP paved track is a kind of ballast reinforced track using the prepacked concrete technique. The most important thing to design the paved track is to optimize the track structure considering various conditions. In this study, the CMP track is constructed(30m) on a test line and the track performance tested by running train to evaluation the capability and workability. The track performance are tested to confirm the vibration acceleration of the car body, wheel and track, accumulated settlement, track irregularity and crack of surface.
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An active application of concrete track is being expected for the future construction of Korean railroad. For the successful concrete track construction and design in earthwork areas, the residual settlement should be reasonably estimated using the proper method. The concrete track is extremely vulnerable to the damage of residual settlement. However, at the transition areas such as bridge approach, differential settlement will likely occur due to difference of stiffness, poor drainage and poor ground treatment. The maintenance is very difficult for excessive settlement on existing line, it is need to constrain the residual settlement in step of design. In this paper, it is performed the determination of the allowable residual settlement through various study to understand the residual settlement behavior of concrete track roadbed.
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In 1st Phase Kyeong-Bu High-Speed Line, to lessen the impact in the transition zone between concrete slab track(in tunnel) and ballasted track(on embankment), the ballast bonding method has been adopted. However, in this area, in the beginning of the operation, unsupported sleepers are found, and the track deterioration and damage of concrete sleepers have occurred. In this paper, the status and causes of unsupported sleepers are discussed and several repair measures are proposed.
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As it recently appears that Life Cycle Cost Analysis may be considered as new methodology for economic valuation of infrastructure many researches have been made to assess LCC(Life Cycle Cost) of each facility based on a reasonable methods. In general, LCC is composed of construction cost and expected maintenance repair cost. And especially, maintenance repair cost must be estimated to enhance the reliability through systematic and reasonable methods. However in Korea, because high speed railway steel bridges are recently constructed no direct statistical data are available for the account of the maintenance cost and then their maintenance characteristics are not linear yet. Therefore, the approach proposed in the paper utilizes a theoretical determination and degradation of the corrosion and fatigue of the bridges based on Rahgozar et al.(2006)'s model on fatigue notch factor considering into the corrosion to incorporate the corrosion effect into the fatigue strength reduction model. And then, the corresponding probability of failure is calculated in terms of the reliability index using S-N curve to formulate the fatigue limit state. Therefore, this paper proposes the minimum Life Cycle Cost through optimum maintenance plan analysis of high-speed railway steel bridges under construction. Finally, this paper reviews the proposed model in oder to confirm the applicability and feasibility by appling it to high speed railway steel bridges under construction
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건설교통부는 2007. 1. 1 (2009.12. 신구좌표병행) 세계측지계 전면 시행 방침에 따라 철도측량의 내실화 그리고 기술력 제고를 위하여 호남고속철도건설 사업수행에 요구되는 수치지도를 항공측량을 통해 제작하였으며 이와 함께 철도기준점(GPS 정밀 3등기준점)측량을 실시하여 보다 정밀한 철도 중심선형 좌표값 과 수준값을 획득할 수 있었다. 국토지리정보원은 측지좌표계로의 변환을 위해 국가좌표변환계수 및 왜곡량 모델을 고시하였다. 이러한 좌표변환은 공통기준점(Common Point)의 성과 및 망구성의 강도(strength), 기준점밀도 등에 의해 결정된다. 호남고속철도의 경우 좌표변환을 위해 공통기준점을 새로히 설치하지 않고 중심측량 및 종횡단측량을 위해 이미 구축된 철도기준점을 공통기준점으로 가정하여 변환을 실시하고자 한다. 따라서 본 논문은 남북축으로 계획된 호남고속철도 사례를 통해 현재의 계획노선을 선형 중심축으로 가정하고 철도기준점을 이용한 좌표변환을 실시후 결과에 대한 분석을 통해 변환가능성 여부를 판단하고자 한다. 좌표변환 실시 후 분석결과 Y축 왜곡량 값이 최소 21cm에서 최대 40cm까지 완만한 직선축으로 감소함을 확인할 수 있었고, X축은
$14cm{\sim}29cm$ 의 왜곡량을 보였으며 이러한 왜곡량을 보정한 결과 좌표간 편차량이$6mm{\sim}9mm$ 로 국토지리정보원의 세계측지계 변환지침에 에 따른 허용오차 및 지적경계측량 허용오차인 10cm를 만족시켰다. 따라서 철도기준점을 공통기준점(Common Point)으로 이용한 철도중심선형의 좌표변환이 가능함을 알 수 있었다.<0.05), 부착치은의 폭경에서는 유치 초기와 그 계승영구치 최종값사이에 통계적으로 유의성 있는 차이가 나타나지 않았다. 5. 점막치은 문제 발현 빈도는 남녀에 상관없이 유치열은 상하악 제 1유구치가, 영구치열은 상하악 모두 제 1소구치가 최고치를 나타냈으며 유치에서보다 그 대응 계승영구치에서 그 빈도가 더욱 높게 나타났다. 연령증가에 따라 점막치은 문제의 발현 빈도는 유치열, 영구치열에서 모두 감소하였으나, 하악 제1유구치, 하악 영구 견치, 제1, 제2소구치의 경우 연령의 증가와 상관없이 비슷하게 유지되거나 증가하는 경향을 보였다.합필름에서 PET/PVDC/Al-vac/PE필름은 장기저장시 사용이 좋을 것으로 사료된다. 2) 질소가스 및 탄산가스투과도 각각$61.6{\mu}PVDC/PE/Al-vac/CPS\;12.5,\;59.8>96.9{\mu}PE/PVDC/PE\;7.1,\;42.0>79.3{\mu}ET/PVDC/L-LDPE\;6.4,\;34.2>72.2{\mu}PET/PVDC/PE/Al-vac/PE\;0.74,\;4.2cc/m^2.24hr{\cdot}atm$ 으로 가장 우수한 PET/PVDC/PE/Al-vac/PE 복합필름이 장기저장용으로 이용이 좋을 것으로 사료된다.태발생을 연구하는데 기초적인 자료로 활용될 수 있을 것으로 사료된다. 조사한 결과 유의확률이 0.05 이하인 수치들은 Hb과 Albumin, K, Na간, Neutrophil과 Leukocyte간이었고 상관계 수치는$0.370{\sim}0.442$ 사이로 나타났다. 유의확률 0.01이하로 조사된 수치는 Cholesterol과 ALT간, LD -
Anemometers to examine the characteristics of the natural wind in the vicinity of the railway track has been installed in two spots, one at the Cheon-Asan station of the Seoul-Busan high-speed line, and the other at the Daechon station of the Changhang conventional railway line in 2006 to examine the characteristics of the natural wind around the railway track to estimate the actual wind speed acting on the train and to develop the wind gust model consisting with the Korean climate condition. The measured data shows that the instant wind velocity frequently exceeds the velocity of train speed restriction, 20m/s, and the actual wind velocities measured in the vicinity of the track are larger than the that measured by the Korean Meteorological Administration(KMA) because the anemometers are installed on the highly-elevated bridges.
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Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of civil infrastructure is rapidly growing unprecedentedly in civil engineering practice. Accordingly, it is expected that the life-cycle cost in the 21st century will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, so far, most researches in Koreahave only focused on roadway bridges, which are not applicable to railway bridges. Thus, this paper presents the formulation models and methods for uncertainty-based LCCA for railroad bridges consideringboth objective statistical data available in the agency database of railroad bridges management and subjective data obtained form interviews with experts of the railway agency, which are used to anew uncertainty-based expected maintenance/repair costs including lifetime indirect costs. For reliable assessment of the life-cycle maintenance/repair costs, statistical analysis considering maintenance history data and survey data including the subjective judgments of railway experts on maintenance/management of railroad bridges, are performed to categorize critical maintenance items and associated expected costs and uncertainty-based deterioration models are developed. Finally, the formulation for simulation-based LCC analysis of railway bridges with uncertainty-based deterioration models are applied to the design-decision problem, which is to select an optimal bridge type having minimum Life-Cycle cost among various railway bridges types such as steel plate girder bridge, and prestressed concrete girder bridge in the basic design phase.
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Open-Steel-Plate-Girder railway bridges, in general, have plain concrete gravity pier without piles at foundations. Such piers are vulnerable to be overturned against braking forces and ground shakings during an earthquake. Thus, this study suggests a strengthening method using earth anchors to improve the resistance of plain concrete gravity piers to the overturn of themselves. Also, a filed test was performed for the as-built and the strengthened pier and the test results were compared to assess the strengthening effect. The earth anchors increased the ultimated capacity for the pier's overturn. Finally, a FE analysis was conducted using nonlinear elements for soil to understand the distribution of the soil stresses for the as-built and the strengthened pier.
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모노레일시스템은 차량외관의 친밀성, 교량 상하부의 슬림한 구조, 저렴한 공사비, 짧은 시공기간 등 미관, 경제성, 시공성에서 다양한 장점이 인정되어 시가지 경량전철의 유력한 대안으로서 여러도시에서 검토 및 제안되고 있다. 또한, 최근에 대구시에서는 도시철도3호선의 시스템으로 모노레일을 채택하여 기본설계를 진행하고 있다. 이러한 국내의 추세에 맞추어 본 고에서는, 해외사례와 현재 수행중인 대구도시철도 기본설계를 중심으로 하여, 모노레일교량의 계획 및 설계에 관한 주요사항을 소개하였다. 먼저, 해외의 모노레일 교량 사례를 분석하였으며, 대구도시철도3호선 기본설계에서 적용하고 있는 주요설계기준을 소개하였다. 또한, 과좌형 모노레일의 대표적인 구조형식인 PSC궤도빔과 강궤도빔에 대하여 계획, 설계 및 제작 방법을 개괄적으로 설명하였다. 본 고의 내용이 모노레일 교량의 계획 및 설계에 관심이 있는 기술자들에게 도움이 되기를 기대한다.
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The vertical forces in rail fasteners at areas of bridge transitions near the embankment and on the pier will occur due to different deformations of adjoining bridges caused by the trainloads, the settlement of supports, and the temperature gradients. The up-lifting forces is not large problem in the blast track because the elasticity of blast and rail pad buffs up-lifting effect. But, it is likely to be difficult to ensure the serviceability of the railway and the safety of the fastener in the end in that concrete slab track consist of rail, fastener, and track in a single body, delivering directly the up-lifting force to the fastener if the deck is bended because of various load cases, such as the end rotation of the overhang due to the vertical load, the bending of pier due to acceleration/braking force and temperature deviation, the settlement of embankment and pier, the temperature deviation of up-down deck and front-back pier, and the rail deformation due to wheel loads. The analysis of the rail fastener is made to verify the superposed tension forces in the rail fastener due to various load cases, temperature gradients and settlement of supports. The potential critical fasteners with the highest uplift forces are the fastener adjacent to the civil joint. The main influence factors are the geometry of the bridge such as, the beneath length of overhang, relative position of bridge bearing and fastener, deflection of bridge and the vertical spring stiffness of the fastener.
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In construction of high speed railway, the fan shape is limited to achieve reduction of required travel time and concrete railway which has structural stability and induces small maintenance cost with allowable ground settlement is recently applied. So construction of concrete railway on soft ground in which considerable ground settlement occurs increases and settlement management in soft ground section is required. Field monitoring on ground movement and integrated geotechnical information system which manages construction, design, and field monitoring data are essential for settlement management of concrete railway subgrade. Site investigation data are also required due to future repair work. Therefore in this study, integrated geotechnical information system for construction and maintenance of concrete railway is developed. The developed system consists of a database and an application program. The database contains site investigation, construction, design, and field monitoring data throughout a railway. Application program performs various functions on managing and utilizing information in the database with graphic visualization of output. And by providing integrating information with comprehensible visual displays, the applicability and effectiveness of the developed system for construction and maintenance management were confirmed.
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In the past decades, complain about ground vibration and noise induced by pile driving has been quickly increased. Because of that, auger drilled piling methods have frequently used specially in urban area. However, the present auger drilled piling methods induce inevitable ground disturbance as well as a certain degree of vibration and noise due to the final hammering. For these reasons, a new auger drilled piling method is required to be developed. This paper introduces PDT(Pulse Discharge Technology) piling method and presents the characteristics of bearing capacity. The PDT piling method is to install in-situ piles using electric power so called Pulse. The pile installed by PDT appears to be able to develop shaft and end bearing capacity efficiently. This paper introduces PDT(Pulse Discharge Technology) piling method, which is the 512nd new construction technology. The PDT piling method is to install in-situ piles using electrical power so called Pulse power. The pulse power is physical value that indicates the energy change per unit time(dE/dt). Since the pulse power is to push ground, using the pulse power is enable a hole to be expanded as well as the ground to be improved by compaction. Therefore, The pile installed by PDT appears to be able to develop shaft and end bearing capacity efficiently. In this study, couples of pile loading tests were carried out to figure out whether or not the PDT piling method is applicable to constructions like rail road facility. As a result, it was concluded that the PDT piling technique meet the requirements for such a rail road related construction.
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Urban flooding with surcharges in sewer system was investigated because of unexpected torrential storm events these days, causing significant amounts of human and economic damages. Although there are limitations in forecasting and preventing natural disasters, integrated urban flooding management system using the SWMM(Storm Water Management Model) engine and Web technology will be an effective tool in securing safety in operating rubber-tired transportation system. In this study, the study area, located in Chuncheon, Kangwon province, was selected to evaluate the applicability of the SWMM model in forecasting urban flooding due to surcharges in sewer system The catchment are 21.10 ha in size and the average slope is 2% in lower flat areas. Information of subcatchment, conjunctions, and conduits was used as the SWMM interface to model surface runoff generation, water distribution through the sewer system and amount of water overflow. Through this study, the applicability of the SWMM for urban flooding forecasting was investigated and probability distribution of storm events module was developed to facilitate urban flooding prediction with forecasted rainfall amounts. In addition, this result can be used to the establishment of disaster management system for rainfall safety of rubber-tired tram in the future.
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In this paper some sets of numerical simulations for passenger evacuation in a fire occurred underground station under various smoke-control ventilation modes. Passenger evacuation flows are calculated by EXODUS program. As input data for EXODUS program, distributions of temparature, smoke and toxicity due to fire in the underground station are evaluated by Fire Dyanamic Simulator (FDS).
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Under various tunnel fires, smoke average temperature and volume flow rate in a tunnel fire are calculated. To obtain realistic results, enthalpy of smoke which composites combustion gases and entrainment air is calculated from curvefit polynomials by temperature.
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Since KHSL 2nd phase was adapted as a main track design, the interests of concrete slab track system have been gradually increased in the division of rail track engineering and many engineering companies have been trying to adapt a concrete slab track system at this moment. Advantages of this system proved in advanced country, japan and Germany etc. are excellent maintenance, track stability and increasing of buckling resistance This developed turnout is same with the KHSR 1st phase's design and applications rules, components and signaling system since it observes KTX specification. Comparing it with the former turnout, High-elasticity pad, lubrication-free roller slide plate and Rheda2000 PC sleeper are only different. The purpose of this study is the development of high speed turnout on concrete slab track and its application on site. Now these studies are going to show the verification and confidence about the interface between ballast-track and concrete slab track by finding and solving the possible problems when it is installed on site and to make these turnouts applied perfectly and completely on concrete slab track. Its first trial construction in korea had been successfully completed at Sangju-station on July 20th ,2007 thanks to KORAIL and KR. Hereunder Sampyo E&C trys to introduce all of turnout technologies on concrete slab track system with Rheda 2000 sleeper
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철도의 토양오염은 크게 총석유계탄화수소(total petroleum hydrocarbon, TPH)에 의한 오염과 중금속류에 의한 오염으로 구분할 수 있다. 이중 TPH 오염은 디젤과 윤활유에 의해서 발생한다. 본 연구에서는 철도 윤활유 유래 오염토양을 정화하기 위해 토양세척방법, 화학적 산화법, 초음파 추출법의 타당성을 연구하였다. 디젤 유래 오염 토양의 토양세척에 많이 사용되는 비이온성 계면활성제는 윤활유 유래 오염 토양의 정화에는 효과적이지 않았다. 다양한 종류의 알코올과 계면활성제를 함께 사용한 경우, 계면활성제만 사용한 경우보다 효과적이었다. 따라서 TPH 오염 철도 토양의 TPH의 오염원에 따라 다른 방법을 적용하는 것이 정화효율을 높일 수 있다.
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철도에서 유래한 중금속 오염 토양을 정화하기 위해 세척방법의 타당성을 연구하였다. 유기산과 무기산을 사용하여 중금속 세척효율을 비교한 결과 무기산이 유기산보다 우수한 효과를 나타내었다. 일반적으로 세척효율이 우수하다고 알려진 ethylene diamine tetraacetic acid (EDTA)는 본 오염 토양의 세척에는 효과적이지 않았다. 무기산 중에는 HCl이 제일 우수한 효과를 보였으나, 세척효율은 0.5 M 에서도 30% 수준이었다. 특히 Zn와 Ni의 제거율이 다른 중금속에 비해 낮았다. 이는 Zn 와 Ni의 토양오염공정시험방법 상의 분석법이 왕수 추출에 의한 전함량이기 때문에 더 낮은 것으로 사료된다. 다른 중금속은 비교적 높은 70% 이상의 세척효율을 얻을 수 있었다. 결과적으로 단순한 세척공법은 중금속 유래 철도오염 토양을 처리하는데 적합하지 않다.
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An active application of concrete track is being expected for the future constructions of Korea railroad. For the successful construction and design in embankment section, the roadbed behavior should be reasonably estimated using the proper analysis method. In this research, behaviors of reinforced roadbed constructed with the determined stiffness and thickness at embankment section were estimated through various design parameters and numerical analysis. A three dimensional finite element method was employed to determine the proper reinforced roadbed thickness at embankment section. The displacement and vertical stress caused by train loading were estimated and compared with the field test results. The bearing characteristics of concrete track roadbed were presented. Moreover, the method to determine thickness of reinforced roadbed was proposed.
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Urban transit or subway stations generally service for a long period of several decades. And, the urban transit or subway is public transportation which lots of people takes every day. During the service time, they are inevitably damaged from environmental corrosion, material aging, fatigue, and the coupling effects with long-term loads and extreme loads. The included damage accumulates and performance degenerates due to the above factors. They would inevitably reduce the resisting capacity of station against the disaster; even they result in collapse with the structural failure under extreme loads. And, if disaster such as earthquake, fire, etc. happens, it causes huge property damage and threatens the human lives. Because of these above reasons, the intelligent health surveillance system should be researched and developed for ensuring the safety of station. In this paper, the research plans of the intelligent health surveillance system of urban transit station are presented. And also, the development or establishment directions of this system are suggested.
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This project of total city plan is developed for the area of DONGDAEGU station in the field of new city-core which is adapted for a forefront city and rational restructuring of the city space and improving for balanced growth according to the first phase operation of Korean high speed line and its complete construction to BUSAN. Bring a new heart of this city of the area of DONGDAEGU station which is a gateway to DAEGU city so that the area contrives a new creation of the city space, balanced developing and activation of a region economy. Deliberate for plan of private capital for harmonious to develop a territory of station therefore it raises an emblem of DAEGU city and activates an economy of the city according to the new trend of the condition of transportation integrated administration of a large regionand new development of DONGDAEGU station.
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철도교량의 경우 교면방수 시공 후 방진매트, 궤도자갈 및 침목부설, 레일 설치 등의 후속공정이 뒤따르고, 시공 및 경제적인 여건으로 인해 위의 공정이 연속적으로 시행되지 못하고 일정 구간 단위로 후속공정이 이루어지는 특수성을 갖고 있다. 이로 인해 교면방수 시공 이후 표면의 노출이 장기화 되는 것이 불가피한 실정으로, 시간 경과에 따른 열화현상으로 인해 발수재의 분해 및 용출이 발생하여 방수시공 초기의 침투깊이를 유지하지 못하고 있는 경우가 많다. 이처럼, 철도교량이 갖고 있는 시공적인 특수성과 궤도자갈이 부설되지 않고 영구적으로 표면이 노출되는 부분을 고려한다면 표면의 장기적인 노출에도 방수성능이 저하되지 않는 내구성을 갖고 있는 방수공법을 선택하는 것이 무엇보다 중요하다고 할 수 있다. 본 연구의 목적은 장기간 표면노출에 따른 열화현상을 방지하는 열화억제형 방수공법(DRA방수공법)에 대하여 시험시공을 통한 객관적인 분석 결과를 도출하고, DRA 방수 공법의 KNOW-HOW를 습득하는 것으로, 이를 통하여 철도교량의 교면방수 열화현상으로 인해 발생하는 하자를 방지하여 잦은 보수와 보강으로 인한 경제적 손실을 최소화하고 현장에서의 시공관계자들이 방수공법을 선정하는데 따른 합리적인 판단 기준을 제공하는데 있다.
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The cement-asphalt mortar is a mixture of cement and asphalt emulsion, and is utilized as a underpouring materials for the railway track which is used to fill under slab panel space so as to provide a stabilized track support and a tool for reduction of noise and vibration. To increase the workability of grouting, this study investigates the effect of temperature on cement-asphalt mortar by analyzing its physical and mechanical properties before/after hardening according to the temperature (10, 15, 20, 25,
$30^{\circ}C$ ). According to the test results, it is found that as for the physical property of fresh cement-asphalt mortar the more mixture temperature become higher or lower, the more fluidity become worse. But by increasing reducing agent amount and its unit quantity, the required fluidity is met. The compressive strength as physical property of hardened cement-asphalt mortar become lower when temperature is lower but taking it by and large the physical properties of cement-asphalt mortar before/after hardening aren't so affected by temperature and well satisfy the requirement. And it has proved that rate of expansion and freezing and thawing resistance aren't affected by temperature. -
The purpose of a railway track is to provide a smooth surface for safe and economical train transportation. The performance of the track results from a complex interaction of the track and subgrade components in response to train loading and environmental actions. In the past, the role of subgrade as the track foundation were not recognized adequately. There are insufficient information and inadequate methods for subgrade design, assessment and improvement. This situation has survived for a long time largely because a subgrade defect can often be adjusted by adding more ballast under the ties or applying more frequent track maintenance. Therefore, the application of reinforced roadbed technology will be expected to increase in the future. The reinforced roadbed thickness is set depending on subgrade reaction modulus(
$K_{30}$ ) in the condition of upper subgrade through PBT in both conventional railroad and KTX railroads. As train velocity (V), train passing tonnage (N), and train axial load (P) are not considered in design, the roadbed thickness could be overestimated (or underestimated). Therefore, in this study has proposed a determination method of reinforced roadbed thickness using design chart made by resilience modulus and properties of earthwork materials. -
Recently, the high speed railway comes into the spotlight as the important and convenient traffic infrastructure. In Korea, Kyung-Bu high speed train service began in about 400km section at 2004, and the Ho-Nam high speed railway will be constructed by 2017. The high speed train will run with a design maximum speed of 300-350km/hr. Since the trains are operated at high speed, the differential settlement of subgrade under the rail is able to cause a fatal disaster. Therefore, the differential settlement of the embankment must be controlled with the greatest care. Furthermore, the characteristics and causes of settlements which occurred under construction and post-construction should be investigated. A considerable number of studies have been conducted on the settlement of the natural ground over the past several decades. But little attention has been given to the compression settlement of the embankment. The long-term settlement of compacted fills embankments is greatly influenced by the post-construction wetting. This is called 'hydro collapse' or 'wetting collapse'. In spite of little study for this wetting collapse problem, it has been recognized that the compressibility of compacted sands, gravels and rockfills exhibit low compressibility at low pressures, but there can be significant compression at high pressures due to grain crushing by several researchers(Marachi et al. 1969, Nobari and Duncan 1972, Noorany et al. 1994, Houston et al. 1993, Wu 2004). The characteristics of compression of fill materials depend on a number of factors such as soil/rock type, as-compacted moisture, density, stress level and wetting condition. Because of the complexity of these factors, it is not easy to predict quantitatively the amount of compression without extensive tests. Therefore, in this research I carried out the wetting collapse tests, with focusing in various soil/rock type, stress levels, wetting condition more closely.
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It is very important to evaluate the reliable deformational characteristics of soils not only in the analysis of geotechnical structures under working stress conditions as foundation in railroad or road system but also for the soil dynamic problems. Different testing techniques are likely to have different testing conditions as strain amplitude, stress level, loading frequency and number of loading cycles. The deformational characteristics of soils can be affected by these variables. In this paper, the effects on modulus of soils subjected to cyclic load were investigated. For the evaluation of deformational characteristics of soils subjected cyclic load, various testing such as TS, RC, TX, and FFRC tests were performed. It was shown that the modulus evaluated by various testing methods are comparable to each other fairly well when the effects of these factors were properly taken into account. For reliable evaluation, therefore, those effects on the modulus need to be considered, and measured values should be effectively adjusted to actual conditions where the soil is working.
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Recently, precast concrete tracks are replacing ballast track for efficient and economic maintenance of track. Precast concrete railroad tracks are manufactured in factory, and transported to railroad construction site for installation. Therefore, quality of precast concrete track itself should be sufficiently good. On the contrary to the convenient manufacturing of precast concrete track, the installation of a precast concrete track requires careful steps. Typically, a precast concrete track is placed on an approximately 15-cm thick lean concrete layer. A mortar is filled between lean concrete layer and precast concrete track to adjust the sloping angle of a precast concrete track for a safe train operation at a curvy section. Then, the use of filled mortarproduces a void underneath a precast concrete track, which is harmful to structural safety of a precast concrete track undercyclic loading. Therefore, it is essential to make sure that there is no void left beneath a precast concrete track after mortar filling. In the continuous resonance method, the amplitude of frequency response measured using an instrumented hammer and an accelerometer is plotted against a pseudo-depth, which is half of the wave velocity divided by frequency. The frequency response functions are measured at consecutive measurement locations, 6-cm interval between measurement points, and then combined together to generate a 2-D plot of frequency response. The sections with strong reflections or large amplitude of frequency response are suspicious areas with internal voids and unfilled areas. The 2-D frequency response plot was efficient in locating problematic sections just by examining the color shade of a visualized plot in 2-D format. Some of the problematic sections were drilled to make a visual inspection of mortar filling. The visual image of interface between mortar and precast concrete track was verified using the validity of the continuous resonance technique adopted in this research.
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In this study, Among various rail track systems, Ballast and concrete track system of Seoul-Busan High-speed Line was adopted to quantify the amount of environment load through the LCA technique. It was intended to compare the results of both track systems through investigating life cycle inventory and gathering the material and energy flows of each track system. With applying the LCA technique to railway infrastructure, which simple maintenance was considered in the past, fundamental technology can be established for the sustainable development in the railway construction industry.
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This study is on the fire resistance evaluation method, expecially on the toxicity of smoke gases generated from the fire, of materials for railway car and structures. Until now, Although international standard related to the quantifying evaluation method of smoke gas is provided but the specific procedure is not contained. On this reason, Test results of toxicity show deviation with the different technique being applied. For now, In advanced railway country, various instrument, like ion chromatography and etc., is used but FT-IR is recommended due to its lots of advantages. while FT-IR has a lot of strong points but still has some problems like water vapor interferences. In this paper, To improve credibility and repeatability of FT-IR it contains some technical solutions in quantifying the 8 toxic components.
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Proposed herein is a shape design of a different rail support block with existing ones for the commercialization of the urban maglev. The rail support for existing test lines adopts monoblock steel sleeper, whereas an individual support system has been proposed to achieve an additional cost savings and to provide an emergency exit. Also, to enhance the easiness of installation and the repairability, alignment adjusting methods suitable for the new design have been devised.
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For the commercialization of the urban maglev, an articulated turnout which consists of several segments of turnout girders and where switching is done by rotating those segments is under development. In this paper, to determine the alignment of this articulated turnout, the requirements for the alignement are analyzed. Requirements include: those for the levitation control and for the ride comfort. For the levitation control, rail joint width should be limited to a certain value, and for the ride comfort, the lateral acceleration and the time derivative of the lateral acceleration satisfy a guideline. According to these requirements, the alignment criteria are discussed.
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본 연구는 미기압파 해석에 필요한 각종계수의 도출 및 해석결과의 신뢰성을 검증하기 위한 목적이 있다. 본 실험에 사용된 터널 주행 열차모형 실험 장치는 1/60축척으로 제작 되었으며, 열차는 KTX 차량 모델의 제원에 맞추어 10량 1편성으로 제작된 모형을 사용하였다. 터널의 다면적은
$107.9m^3$ 와$95.1m^3$ 를 적용하고, 터널연장은 1km, 0.78km, 0.5km를 적용하였고, 열차속도는 275, 300, 325, 350km/h로 변화시켜 실험 하였다. 실험 장치는 유압발사 시스템으로 열차모델 유압 발사기터널모델 제동장치로 구성된다. 모형열차의 속도는 터널입구 전방 및 출구 부 갱구에서 각각 1.2m지점에서 설치한 속도 감지기에 의해서 측정되며, 터널 내부의 압력변동은 압력센서를 터널의 입구, 중앙, 출구부에 설치하여 연속적으로 측정 하였다. 측정결과 터널입구에서 발생한 압력파의 압력기울기는 터널을 전파하면서 비선형효과에 의해서 증가하거나 확산작용에 의해서 압력기울기가 감소하는 것을 알 수 있었고, 미기압파 저감 대책을 위해 터널입구에 종류별 각각 설치하여 출구부에서 발생되는 미기압파를 비교분석하여보았다. -
본 연구는 플랫폼 스크린도어가 설치된 역사에서 화재시 스크린도어에 의한 효과와 화재에 대한 방재연구를 체계적으로 진행하기 위한 기초연구이다. 본문에는 스크린 도어의 종류와 특징에 대하여 기술하였다. 본 연구의 대상이 되는 스크린 도어에는 완전밀폐형이 설치된 역사를 대상으로 하였으며 승강장 종류는 섬식 승강장이다. 스크린 도어가 설치된 역사의 화재유동 전산수치모사에 화재전용 CFD code를 이용하여 수행하였다. 플랫폼 스크린도어의 영향을 분석하기 위하여 스크린도어가 설치된 경우와 설치되지 않은 경우를 해석 하였다. 또한 화원의 위치는 승강장과 선로부에 있는 경우로 나누었다. 화원의 성장시나리오는 Ultrafast model로 하였으며, 화원크기는 10MW로 하였다. 해석결과 플랫폼 스크린도어가 설치된 경우는 화원의 위치가 승강장에 있을 때 온도 및 연기의 전파가 주 탈출구인 계단에까지 4분 이내로 전파된다. 선로부에 있을 때는 스크린 도어에 의해 열, 연기 전파의 차단 효과가 있었다.
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2003년 대구 지하철(중앙역) 화재 사건 당시의 화재 유동 및 승객 피난 시뮬레이션을 수행하였다. 화재 발생 첫 지점은 중앙역 지하 3층 객차 내부이며, 지하 3층과 지하 2층의 화재 및 연기 유동을 FLUENT 6.2를 이용하여 수치해석 하였다. 화재 객차 및 승강장에서의 이산화탄소 및 온도분포를 예측하였으며, 수치해석을 통하여 구해진 data는 승객 피난 시뮬레이션(EXODUS)의 입력 인자로 사용되었다. 수치해석에서 가장 높은 온도는 1500K로 조사되었다. EXODUS를 이용하여 지하 3층에서 지하1층까지 승객 피난 시뮬레이션이 수행되었으며, 총 피난 승객은 1000명으로 가정하였다. 이중 640명은 객차 내부에, 360명은 승강장에 존재하는 것으로 하고 계산을 수행하였다. 피난 시뮬레이션 결과 135명이 사망하였으며 이는 대구 화재 사고결과에 비교적 근접하는 수치이다. 또한 평균 피난 시간은 10분 19초로 조사가 되었다.
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본 연구에서는 실제역사화재 사고인 대구지하철화재사고를 참고하여 화재시뮬레이터의 경계조건으로 시뮬레이션을 수행 하였다. 화재시뮬레이션의 경우는 총 지하 3층의 역사 중 사망자가 가장 많이 발생한 지하3층 역사와 지하2층 대합실까지 모델링하여 시뮬레이션을 실시하였다. 화재시뮬레이터는 CFAST와 FLUENT를 이용하여 수행하였으며, CFAST의 경우는 총 29개의 Zone으로, 지하3층 역사 18개, 지하2층 역사 11개로 나누어 시뮬레이션 하였다. FLUENT의 경우는 총24개의 Zone으로 나누었으며, 지하승강장의 경우는 CFAST의 Zone과 동일하게 설정하였다. 2개의 시뮬레이터에서 나온 결과값들을 비교하여 지하역사 화재시 적용가능성 여부를 연구하였으며, 피난시뮬레이션인 EXODUS를 이용하여 각각의 화재시뮬레이션의 결과를 EXODUS의 HAZARD 경계조건으로 하여 피난 시뮬레이션을 진행 하였다. 화재영향의 적용은 CFAST의 경우 EXODUS로 자동적으로 화재 DATA가 Lode 되는 방식으로 하였으며, FLUENT의 경우는 화재시뮬레이션 OUT DATA값들이 EXODUS와 호환이 어려우므로 직접 결과값들을 수식으로 변환하여 EXODUS HAZARD에 적용하여 승객피난시뮬레이션을 수행하였다. 또한 이를 실제 대구지하철화재사고와 비교분석하였다.
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Seoul Metro continuously converted the standard rail into continuous welded rail since the later part of 1990's, and currently, most of the sectors of the Seoul Metro are continuous welded rails. As the continuous welded rail is inhibited by the contraction and expansion force of the rail as well as rail-bed, this force is stored as the internal stress of the rail with the exception of portion of the both ends of the continuous welded rail. If the contraction and expansion of the rail is restricted, the internal stress, that is, the force in the direction of the axis, is proportional to the cross-sectional area of the rail. Therefore, with regards to the temperature changes, the internal stress changes in accordance with the type of rail, bolting apparatus, railroad tie and rail-bed. As such, the rail temperature becomes important data in securing the gap at the adjoining section of the rail in the standard rail section, and to determine the setting temperature for the continuous welded rail. In addition, it becomes basic data for maintenance of the track. Accordingly, this thesis introduces cases of installation of rail temperature detector in order to prevent and manage track defectiveness due to increase in rail temperature, and to utilize as basic data at the time of various construction and maintenance. Furthermore, this thesis aims to assist maintenance of track through systematic temperature management in the future by looking into means of its utilization.
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고속철도 교량은 고속주행 열차의 차축 주기하중 효과와 교량 고유의 동적특성에 의한 동적 증폭 효과로 인하여 구조물의 안전성에 영향을 받는다. 그리고 교량의 과도한 변형으로 인하여 차륜과 레일의 접촉력 감소, 궤도틀림 등의 윤중 변동이 일어나 열차의 주행안전성 및 승차감을 저해할 수 있다. 이러한 궤도 안전성을 확보하기 위하여 동적거동에 대한 교량상판수준의 수직가속도 제한, 차륜-레일간의 접촉과 열차주행 안전성 확보를 위한 상판 면틀림 제한, 단부 회전각 변위 제한, 차량하중에 의한 교량의 수직 처짐 제한을 반드시 만족시켜야 하며, 필수적으로 공진에 대한 검토도 이루어져야 한다. 신설되는 호남고속철도에서는 기존의 경부고속철도와 다른 콘크리트 도상을 적용하고, 궤도간격, 설계열차하중 등이 변경되어 적용되므로 새로운 동적안정성 요구조건을 적용하게 된다. 본 연구에서는 콘크리트교량에 비해 진동특성이 취약한 것으로 알려진 강합성 거더 고속철도 교량의 동적거동 분석을 수행하였다.
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철도에서 접속구간은 교량과 토공 또는 터널과 토공 사이의 노반상태가 변화하는 구간이나 궤도구조형식이 변화하는 구간을 말한다. 이들 구간에서는 궤도지지강성이 갑작스럽게 변화함으로써 레일변위가 급하게 변화하여 차량의 이상 진동 및 충격윤중이 발생한다. 열차의 진동은 차량의 주행안정성 및 승차감을 저하시키고 충격윤중은 노반의 침하 및 궤도재료의 열화, 손상을 가속시키는 결과를 초래한다. 자갈도상 궤도구조에서의 접속구간은 노반강성이 차이가 생기는 교량경계부와 터널경계부가 가장 보편적인 천이접속형태이며 특히 교량부와 토공부는 각각 일정한 고유의 탄성을 가지고 있어 서로 큰 강성차를 가진다. 교량부와 토공부의 강성차로 인해 궤도에서 발생하는 탄성변위량이 일치하지 않기 때문에 동적윤중은 하부구조의 과도한 변위를 유발시킬 수 있는 큰 충격하중을 발생시키고 이러한 과하중은 토공부의 궤도구성품의 손상을 유발하게 된다. 따라서 현재 국내에서는 접속구간 설계 시 구간별 노반 및 궤도강성차를 줄여 전체적으로 궤도지지강성 변화를 완화시키고, 토공구간의 소성침하 방지와 접속부에 부정적 영향을 주는 노반구조물의 비이상적 거동발생을 방지할 수 있는 규정을 제정하여 이를 바탕으로 설계하고 있으나 실제 운행선에서 발생하는 접속부 궤도의 동적거동을 감안한 설계지침은 아직 미약한 실정이다. 따라서 본 연구에서는 노반강성별 접속부 궤도의 동적거동 특성을 파악하고 노반구조물과 궤도구조의 상호관계를 입증하기 위해 노반강성별 접속부 궤도의 동적응답을 측정하고 측정 및 이론식을 이용한 접속부 궤도의 탄성력 및 궤도부담력을 산출하여 운행선 접속부 궤도의 동적거동을 감안한 설계지침 개발을 위한 기초자료를 제시하고자 한다.F-1^{(R)}$,
$Helioseale^{(R)}$ 에 brush tip을 적용한 경우보다 많이 발생하였다(p<0.05). 3. 기포의 평균 단면적은 Teethmate$F-1^{(R)}$ 가 다른 군에 비해 큰 값을 보였다(p<0.05). 4.$Clinpro^{(R)}$ 와 적용 tip을 달리한$Helioseal^{(R)}$ 의 경우 기포의 발생 빈도, 평균 개수, 평균 단면적 모두 유의차를 보이지 않았다(p>0.05).닌, 집이나 학교와 같은 일상의 생활공간이기 때문에 단순한 주의만으로도 외상의 발생을 예방할 수 있을 것으로 사료된다. 보이지 않았다 (p>0.05). 본 실험에서 시도한 두 가지 진정요법이 비교적 높은 임상적 치료 성공률(II군 : 97.14%, III군 : 88.57%)을 보여 만족할 만한 결과를 나타낸 것으로 평가되었다.tosan film보다 큰 수증기 투과도를 보였다.적으로 유의한 차이를 보이지 않았다.y tissue layer thinning은 3 군모두에서 관찰되었고 항암 3 일군이 가장 심하게 나타났다. 이상의 실험결과를 보면 술전 항암제투여가 초기에 시행한 경우에는 조직의 치유에 초기 5 일정도까지는 영향을 미치나 7 일이 지나면 정상범주로 회복함을 알수 있었고 실험결과 항암제 투여후 3 일째 피판 형성한 군에서 피판치유가 늦어진 것으로 관찰되어 인체에서 항암 투여후 수술시기는 인체면역계가 회복하는 시기를 3주이상 경과후 적어도 4주째 수술시기를 정하는 것이 유리하리라 생각되었다.한 복합레진은 개발의 초기단계이며, 물성의 증가를 위한 연구가 필요할 것으로 사료된다.또 -
The ballast gravels are often contaminated by various pollutants, like diesel fuel, lubricants, and heavy metals. Especially, the gravels near the switching are apt to be polluted by the lubricant. Because this lubricant can pollute the soil of track, the contaminated ballast gravels should be cleaned immediately. In this study, a physical desorption method was used to remove the oil contaminants from the surface of the ballast gravels. Thermosetting resin was used as a media for physical remediation of ballast gravels. The total petroleum hydrocarbon of the gravels was monitored over time. In addition, scanning electron microscopic images were obtained to observe the removal of the oily pollutants from the surface of the gravels.
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By the examination of data collected by long-term measuring system on high-speed railway bridges, it has been known that the atmospheric temperature may affect the responses of maximum deflection and acceleration of bridge deck. Collected data show a tendency by seasonal factor to that, by the decrease of temperature, the response of acceleration of bridge deck increases, and the response of deflection decreases. To trace the cause of this tendency, parametric analysis on the stiffness of bridge bearing and track ballast has been performed, and the in-site measurement has been achieved in high-speed railway line to understand seasonal influences.
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Characteristics of the stress on Continuous Welded Rail(CWR) were investigated to apply to design procedure for railway bridge design. Actions due to change in temperature, braking/traction and bending of the deck were considered in this interaction analysis between CWR and bridge deck. The bridge parameters such as static arrangement of the deck and support stiffness were taken into consideration to examine the influence of the parameters on the additional rail stress. The final results of this study, which include the displacement as well as the stress will be presented in the form of the design chart in future.
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There is growing interest in CBTC(Communication Based Train Control) system in accordance with the development of the communication technologies. The CBTC system, which adopts the moving block, has advantages such as headway and installation cost reduction compared with the existing system with fixed block. For the moving block system, it is required to locate the trains in real-time. Based on EPLRS(Enhanced Position Location Reporting System) technology, the train position can be provided only through the communication between radios. This paper introduces EPLRS based train detection method and verifies its effect by instance.
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This study examined EM compatibility between noise from electric railway and signal of ILS in the case that an AC double track system is located about 1km far from end zone of runway at the airport. ILS is the most major equipment to help give airplane route during the landing.
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The Train Networks has a goal which requires the fast and correct data communication for distributable equipment systems. For this, in 1999, some train makers had established the standard TCN(IEC61375-1) for the inter-operating between equipment systems. Recently, TCN is being used in EU, China and the requirement to use it is growing up by many other countries more and more. The TCN was adopted at Korea High-speed Train with first in Korea, and Rotem Company finished the design of TCMS with TCN network for Istanbul EMU and KTX-2 Train and tests them. TCN(Train Communication Networks) defines the set of communication vehicle buses and train buses. The MVB(Multifunction Vehicle Bus) defines the data communication interface of equipment located in a vehicle and the WTB(Wire Train Bus) defines the data communication interface between vehicles. This paper examines whether the result of on-board test is satisfied with the IEC61375-1(International Electrotechnical Commission 61375-1) which is the international standard of TCN and introduce the results.
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One of the most important targets of transportation is to transport human and commodities to the destination safely. Railway has low risk, compared with land, ocean and flight route and it assures high security as well as high speed driving, since it runs on regular track. However, train accident may result in tragic accident due to small carelessness, so special event recorder is preferably used in order for clarity of responsibility in case of accident, maintenance of signal device and defect analysis. JRU(Juridical Recorder Unit) for ATC/ATS/ATP can be more advanced event recorder. Event recorder of KTX-I which is running now is installed one by one on each leading car and last car, and operation plan of event recorder in case of single trainset is suggested. But regarding train operation of multi-coupled trainset operation such as KTX-II, more detailed study is required for event recorder revitalization and record data process method. Therefore, this research aims at operation plan used in existing event recorder, and suggests effective operation and management plan of event recorder in multi-coupled trainset such as new High Speed Train.
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This paper describes the detection algorithm which can distinguish series arcing signal from voltage harmonics or noises produced by the operation of non-linear loads. A high pass filter with the cutoff frequency of 3 kHz is designed and it can attenuate power frequency signal to 80 dB. Series arcing phenomena is simulated to an incandescent lamp controlled by a dimmer. From the experimental results, it is confirmed that the amplitude of the filter output voltage varies at random during series arcing but the signal generated by non-linear loads appears on a regular basis. We proposed a series arcing detection algorithm using the chaotic nature of voltage signal.
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Standard Gate Turn Off (GTO) Thyristor drive technology results in inhomogeneous turn-on and turn-off transients which in turn needs costly dv/dt and di/dt snubber circuits. Added to this GTO is bulky in size, needs external cooling, slower switching time etc. The development of high voltage Insulated Gate Bipolar Transistor (IGBT) have given new device advantage in the areas where they compete with conventional GTO technology. Indian Railway has developed first IGBT based traction converter and was commissioned in November 2006. Some of the supremacy of IGBT are smaller in size, no external cooling is required, built in power supply which enhances reliability, lower switching losses which leads to higher efficiency, reduced gate drive, high frequency operation in real time etc. These advantages are highlighted along with IGBT Traction system in operation.
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Induction motors are the main driving force of electric vehicles and operated by pulse width modulation (PWM) inverters in speed control. Contrary to full-voltage operation of induction motors, inverter-fed induction motors (IFM) generates transient overvoltages up to 10 kV/us and transient overvoltages accelerate the deterioration of winding insulation. We investigated transient overvoltages produced by the operation of IFM and analyzed its peak value and dv/dt depending on power cable length and operation frequency. The experimental results showed that transient overvoltages measured at the motor terminal increased with the cable length between inverter and motor.
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MAGLEV(Magnetic Levitation) with Middle-low speed be classified as a kind of LRT(Light Rail Transit) in KOREA. Also this vehicle has adopted LIM propulsion method. The MAGLEV has adopted LIM type in operational or developing model in the world. The power rail of LIM is very similar with the 3th rail of LRT in the functional property but the structure and shape of power rail is different with that. WE have to search the optimal power rail system for Korean MAGLEV vehicle. In this paper, we suggest the conceptual design and direction of design for power rail of Korean MAGLEV developing.
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Protective equipments have a very important protection role in power accident on catenary line. These equipments are installed on electrical pole. The poles have complicated with many bands(moveable bracket, branch wire anchor, shield wire, etc). So we have improved bands and installed bands on pole to test technical condition. The Result has showed effectiveness due to fixed position change of fault protective wire and to improve band shape. For example, reduction of band made cost, simplification of installing, correct position of protective wire and shield wire.
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In this paper, the conventional linear induction motor(LIM) used in propelling the MAGLEV in Korea is redesigned in order to reduce its weight. The specifications of the newly designed model for base speed, acceleration, rated thrust and maximum output is respectively 45km/h, 4.0km/h/sec, 5,200[N] and 65 [kW]. Weight reduction effect of the LIM according to the change of pole number from 8 to 6 is shown. Equivalent circuit analysis considering end effect and finite element method are used for the analysis of the redesigned model. Finally the weight reduction ratio of the newly designed LIM to the conventional model, thrust, attraction force, line current, temperature rise, flux density distribution are presented.
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State estimation is to estimate the values of the states that minimize the error between the real states and the measured states, which are usually hampered by noise. It exploits the redundant data and the equality constraints achieved from the power systems. In the electric railway feeding systems, especially, the measured states may have significant level of noise in comparison with the commercial power systems. Since the meters - the sources of the data that include vehicles - are distributed in the long distance along the railroad, they are vulnerable to the signal interference. In this paper we have studied the application of state estimation method to the AT feeding systems and shown that this method can increase the reliability of the measured data.
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In the respect of energy saving and reusing, it is necessary to reduce greenhouse gases emission and to enhance the operation efficiency in electric railway system. Recently, as the power electronics technologies are advanced, some countries have focused on the regenerative inverter to use regeneration energy on each line. When the electric tractions are stopped or slowed down, it is useful to supply the surplus energy to the power source by regenerative system, which increases its energy efficiency. Also, the generated energy can be supply to other tractions or equipments inside traction. Thus, it may help reduce construction cost of additional power plants. The purpose of this study is to describe the development status of the regenerative inverter system which suppress extra DC-line voltage and regenerate the energy instead of using a resister.
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It is important to evaluate the power quality at a substation when a test train is running. Especially, the Korea Electric Power Company(KEPCO) restrict the power quality generated from the electrical train within limited value. So, this paper represents the results of the power quality test when Hanvit 350 is running at the KTX high speed line and the assessment.
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철도시스템은 열차견인을 위한 고전압시스템, 열차제어를 위한 저전압시스템을 사용하며, 철도를 구성하는 시스템이 지형적으로 광범위하게 분포되어 있다. 철도시스템에서 전차선의 지락에 의한 과대한 고장전류, 낙뢰 등에 의한 이상 고전압이 발생되어 사람의 사상 및 기기의 고장이 발생할 수 있는데, 지락에 의한 고장전류, 낙뢰에 의한 고전압으로부터 기기를 보호하기 위해서 접지를 설치한다. 각 시스템에 대한 단독접지를 하는 경우에는 기기 상호가 폐회로가 형성되어 이상전류가 흐르게 되어 기기를 정상적으로 작동시키지 못하는 경우가 있다. 따라서 이러한 해결책으로 등전위 접지시스템을 채용한다. 이러한 등전위 접지시스템은 매우 낮은 접지저항을 확보하여야 한다. 본 논문에서는 철도시스템에서 기존의 단독접지시스템에서 현재의 공통접지시스템으로의 변화 및 두 시스템의 시뮬레이션 비교분석과 앞으로의 새로운 접지시스템에 대한 방향에 대해 제시하였다.
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In this paper, the power simulation is used for the prediction of regenerative energy and examination of install location of regenerative inverter for DC railway system. The power simulation was composed to train performance simulation(TPS) and power flow simulation. We performed the power simulation for Seoul subway line 5 and 7, calculation of regenerative energy and examination of substations where regenerative inverter is installed.
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KORAIL is one of the biggest consumer in electric power market so it is necessary to investigate power consumption pattern and optimize power rates. This paper presents simulation program for electric power rates define program based on billing system database. Base on the substation annual power usage DB data, the characteristic of the substation power consumption are investigated and effective electrical billing system are compared each other. Through this program it is verified that we can save more then several hundred million won for a year. Also electric train air condition power consumption was measured to figure the method how to reduce peak energy consumption.
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In this paper, a unified regenerative inverter system for railway with DC line voltage simulator is proposed. In order to determine the operation characteristics of the regenerative inverter, the DC line voltage simulator is proposed. The DC line voltage simulator, which is based on the AC-DC PWM converter, varies the DC voltage according to the fluctuating voltage which is measured in the actual DC line. The suitable operating point of the regenerative inverter can be estimated from the simulation result. The regenerative inverter operates two modes. When the DC line voltage exceed the operating point, already set up, it works as regenerative inverter to return the excessive power of DC line to the grid. When the DC line voltage is under the operating point, it works as active power filter to compensate harmonic currents. In this paper, the control algorithm of the DC line voltage simulator and that of the regenerative inverter is proposed.
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Electric Power cable is the apparatus that receives electric power from the Korea Electric Power Corporation and supplies electric power to electric train and annex facilities of each railway station. With substantial ripple effect during power blackout accidents, such power blackout accidents must be coped with by discriminating the status of insulation deterioration of electric power cable in advance. Discrimination of insulation deterioration of the electric power cable is normally executed while the power is disconnected and it is very difficult to discover, at early stage, the insulation deterioration of the power cable in operational state since the duration of inspection is limited. This research aims to consider method of diagnosing the insulation deterioration of electric power cable in On-Line state rather than diagnosis in Off-Line state in order to secure reliability of power supply by reducing duration of power blackout (accidental blackout and blackout during works) and by seeking reduction in equipment and manpower used in diagnosis of deterioration through prevention of the accident itself prior to occurrence through early restoration of accident due to insulation deterioration of the electric power cable and assessment of performance of the cable under operation.
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Failure Mode, Effects, and Criticality Analysis (FMECA) is an extension of FMEA which includes a criticality analysis. The criticality analysis is used to chart the probability of failure modes against the severity of their consequences. The result highlights failure modes with relatively high probability and severity of consequences, allowing remedial effort to be directed where it will produce the greatest value. However, there are several limitations. Measuring severity of failure consequences is subjective and linguistic. Since The result of FMECA only gives qualitative and quantitative informations, it should be re-analysed to prioritize critical units. Fuzzy set theory has been introduced by Lotfi A. Zadeh (1965). It has extended the classical set theory dramatically. Based on fuzzy set theory, fuzzy logic has been developed employing human reasoning process. IF-THEN fuzzy rule based assessment approach can model the expert's decision logic appropriately. Fault tree analysis (FTA) is one of most common fault modeling techniques. It is widely used in many fields practically. In this paper, a simple fault tree analysis is proposed to measure the severity of components. Fuzzy rule based assessment method interprets linguistic variables for determination of critical unit priorities. An rail-way transforming system is analysed to describe the proposed method.
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The most critical function of the Communication Based Train Control system is wayside and on-board Radio communication. Radio communication must be safely made without errors. The standards for CBTC has not been established yet, and research on Radio communication systems for use in Train control systems adopting CBTC system such as the magnetic levitation train must continue. This paper will discuss the characteristics of Radio communication technology currently used domestically such as GSM-R, IEEE 802.11, TETRA, MESH, and WiMAX/WiBro, and will investigate the potential possibility of applying them to Train control systems.
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지하철은 대중교통 수단으로서 서울을 비롯한 도시에서는 없어서 안 되는 교통수단으로 자리 잡고 있어 이용하는 계층이 다양하게 구성되어 있다. 이러한 고객의 정보 제공 요구에 부응하기 위하여 다양한 정보표출과 정보통신 서비스 제공을 할 수 있도록 종합관제센터 및 역사에 광통신망이 설치 운용되고 있으며, 통신망 서비스 의존도가 약 95%를 차지함에 따라 안정적 운용은 필수적이다. 본 논문은 광통신망 구축 후 실질적 시스템 운영의 초기단계에서 유지보수 업무를 수행하면서 도출된 기술사항과 경보메시지 분석에 의한 효율적 운용방안을 기술한 것으로서, 현장에서 필요한 실질적 전문기술과 효율적 시스템 운영방식 공유와 동종 기관간의 운영노하우 상호 정보교류를 촉진 시키고자 한다. 도시철도에서의 광통신망은 열차운행을 위한 각종 제어망과 Data망을 수용하고 있어 전문적이고 효율적인 운영방안 정립이 필요함에 따라, 본 논문은 광통신시스템 효율적 운용과 전문조직 구성에 대하여 제시하였다.
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Seoul Metro has been constructing the screen doors on the platforms to provide safe and comfort environments. The screen doors of each station are configured so that they can be operated in automatic mode in connection with ATC/ATO through the integrated control panel in the station control room and in manual mode through the control panel of the station control room and crew control panel. These systems have been implemented with different data communication protocols between systems, HMI configuration, and so on due to ordering processes, implementation time and diverse suppliers, and manufactured to be operated within single station. Seoul Metro has been planning to implement the integrated control system to secure seamless train operation and safety and to have a fast response system against emergency situations such as PSD failure and fire, by implementing the system that is able to collectively manage, monitor and control the operation status and equipment conditions of PSD on to the integrated control center. This paper has studied a scheme to reduce the budget for the future facility constructions by standardizing the data format for data communication with the integrated station control panel and using the open standard protocols, in order to secure consistency of operation, system expansion and maintenance with unified and standardized control items.
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A surveillance system is used many industrial places, and public places to monitor the present situation. Most of the existing surveillance system is composed of the monitors and a lot of cameras that are installed each place to be monitored. The system is usually using the CCTV, closed circuit television, system that is a passive surveillance system. Urban transit operation corporations use the passive surveillance system to monitor the situation of the passengers, and the status of the important facilities. However the officers or operators cannot monitor all of the situation or status constantly, and cannot respond to emergency. In this paper, we propose a sensor network-based intelligent surveillance system to solve these problems. The proposed system is composed of a lot of intelligent sensors that can determine the present status and integrated processor units to detect more precisely events using the information from the sensors. The sensors and the integrated processor are connected by communication network. The proposed system can be installed and used without a lot of change of the existing facilities such as the enormous communication bandwidth increase.
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Urban railway system that leads the urban public transportation enables the passengers to use the subway system safely and conveniently by indicating the destination of, status of approach of and other information on train through Train Destination Equipment(TDE), which is one of the important passenger services. The existing system is composed of Host Station Equipment(HSE) and operator panel that receives necessary input on train information from Total Traffic Control System(TTC), Local Station Equipment(LSE) that controls Train Destination Indicator(TDI) installed at each station, and Train Destination Indicator that ultimately displays train information to the passengers using the train system. This study aims to realize stabilized and reliable announcement system for destination of train by considering processing procedure and method of expression of inputted information of the existing system of notification of announcement of destination of train that can be applied in the RFID, which is the base technology of USN for which service expansion is easy, and to realize system that considers interface with USN and expandability with other facilities in the future.
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In the more and more continues traffic difficulty which comes to be serious it is for solve, in order to like this used plan for new town light train automatic fare collection system, the city development which is balance and the passenger whom it uses, in consequence of the fact that recently believer instruction, the automatic fare collection system the reverse which is convenient is used in the scripture season which is embossed with means it introduces it operates and a manpower with the scientific service control which leads the electric computer anger of passenger service improvement and accounting and statistical business it reduces, the use is convenient and the possibility facility of operating efficiently in rational plan in order to be, description below for the service automation equipment where the efficiency improves it is. Service automation equipment uses a scripture season to be the first boundary gate of the passenger, there must be a place where it uses a service automation facility and in order to be convenient, it considers the moving area and a wait of the reverse station passenger moving area and the space where, must secure the automatic fare collection system which it follows in automation of facility and the service operation of the reverse station which is ticket sale, the collection of tickets back the passenger is convenient and in order it will be able to use, must do and must consider, must arrange the efficient characteristic of the maintenance civil official services.
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A prototype high-speed train system, Hanvit-350, has been developed in Korea since 1996. The train has reached the maximum speed of 352.4km/h during a test run on December 2004. It is presently undergoing various tests to stabilize its performance and to secure reliability. Until now, around 420 runs have been conducted and accumulates 190,000km trial run. The test database management program is developed using existing analysis program, LabVIEW and database program, Microsoft-SQL. The test database management program is used to analysis of test results and will be used to find out the correlation characteristics between parameters.
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Establishing the remote monitoring system of the moving test train is the important issue for the railway systems that provide comfort travel to the passengers. But it is not easy to transmit train's test data to remote site because the train runs tunnels. This paper represent the development results of Hanvit 350 remote monitoring system using wireless data communication system which is installed in the test train. This system can provide both correct positions of unstable track and train's running status such as speed, kilopost and acceleration.
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Energy saving is an important topic for each heavy user of the power system, including railway operators. Therefore, four strategy of train operations studied that maximum speed reduction, reduced acceleration rate, anticipatory coasting, and saw-tooth coasting for energy saving. The Simulation model of the study used to investigate the performance of a railway system, and it was used to study the effect of energy saving strategies for the train operation. The Study investigate train operation strategy for energy saving, investigate the effect of strategy, and find the energy optimization of acceleration, coasting, braking section used Run-Curve simulator from train data.
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LIMs propelling the MAGLEV which has been developed in Korea have 3-series and 2-parallel connection, so that 6 LIMs per one vehicle are fed by one inverter. Thrust performance of the parallel-operated LIMs can be different from each other because of variant magnetic air gaps and electrical impedance. The thrust difference between the parallel LIMs cause a twist force on the vehicle. This paper proposes an algorithm to measure thrust of the parallel-operated LIMs. The method uses a digital signal processor(TMS320F2812), voltage and current sensors. As a result, thrust, flux and currents of the parallel-operated small LIMs which are manufactured in our laboratory are monitored by the developed measurement system.
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In the case of Linear induction motor(LIM), numerical analysis method like Finite Element Method(FEM) has been mainly used to analyze the travelling magnetic field problem which includes the velocity-induced electromotive force. If the problem including the velocity-induced electromotive force is analyzed by FEM using Galerkin method, the solution can be oscillated according to Peclet Number, which is determined by conductivity, permeability, moving velocity and size of mesh. Consequently, the accuracy of the solution can be low and the Loops of flux can be occurred at the secondary back-iron. These loops of flux occurred at the secondary back-iron does not exist physically, but it can be occurred in the analysis. In this case, the loops of flux can be generally removed by using Up-Wind method which is impossible to apply a conventional S/W tool(Maxwell 2D). Therefore, in this paper, authors examined the Loops of flux occurred at the secondary back-iron of LIM according to variations of Peclet Number, and analyzed whether these loops of flux affect on the thrust force characteristics of LIM or not.
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This paper presents a characteristics of linear induction motor considering airgap variation for railway transit in order to achieve high performance of the vehicle. The operating principle of a LIM(Linear induction motor) is identical to a rotary induction motor. Space-time variant magnetic fields are generated by the primary part across the airgap and induce the electro-motive force(EMF) in the secondary part, a conducting sheet. This EMF generates the eddy currents, which interact with the airgap flux and so produce the thrust force known as Loren's force. Even though the operating principal is exactly same as a rotary motor, the linear motor has a finite length of the primary or secondary parts and it causes static and dynamic end-effect which is the discontinuous airgap flux phenomenon. This end-effect causes the deterioration of the system performance, especially in high-speed operation. Another problem is that construction tolerance restricts the minimum airgap in order to prevent a collision between the primary part and the secondary reaction plate. More over, as the airgap length is getting smaller, the attraction force between the primary part and secondary parts is getting larger dramatically and the attraction force would be another friction against propulsion. Therefore, it is necessary to figure out the characteristics of linear induction motor considering airgap variation in order to achieve high performance of the vehicle. The dynamic model of LIM taking into account end-effects is derived. Then the modified mechanical load equation considering the effect of the attraction and thrust force according to the airgap variation is analyzed. The simulation results are presented to show the effect of the LIM according to the airgap variation.
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Recently, embedded systems role as control systems instead of mechanical control systems in many parts of vehicles. In cases that embedded systems are used controling the electric signal, it is important to secure the reliability of a software within embedded systems. In this paper, the test platform for securing the reliability and real-time characteristic of the embedded system that controls electric signal of All Wheel Steering Control System in a Bi-modal tram is proposed. The platform is built on a HIL (Hardware In the Loop) architecture. Through the HIL platform, various vehicle conditions, driver activities and environment conditions can be successfully tested without actual driving, hence improving the reliability of the embedded system for the All Wheel Steering Control System.
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Power Car PC1 and PC2 of Korean high speed train have a auxiliary block which consists of two PWM converter respectively. If a auxiliary block happens a critical failure, the other supplies power to full load of train. In this case, a stability of auxiliary block reduces by a increasing load. For increasing a stability of auxiliary block and train system, a auxiliary block consists of two group four PWM converter which operates simultaneously. If a group of a auxiliary block happens a critical failure, the other supplies power to load of a auxiliary block. This paper describes a method for simultaneous movement of auxiliary block which consists of two group four PWM converter.
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The Five Days Work System started to be lately introduced among Korean companies is causing much interests in diverse aspects. This theme of '5 days work' seems like a hot issue both for academian and for practitioner in the respect that it incurred a great change and impact in worker's life. The purpose of this article is to depict the pattern and the effect incurred by '5 days work system', focusing on the female workers in railroad-related organizations. To attain this purpose, several aspects of current '5 days work system' and its effects both on work life and on family life are surveyed through questionaire and analyzed by SPSS. And some implications will be supposed. in based on the cognitive response of employees.
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Subway station is installed with equipment of deficient ventilation and air purification in need of routine activity for users because projectors didn't have recognition of the importance of prevention equipment on disasters in subway stations. So if the accident in Deagu is occurred again, we can't prevent it. And it is urgently necessary to improve antique subway station for the safety and service to citizens because users were increased far more. Improvement of subway station has to be modernized the backward and antique subway station and maintained and developed by the center of traffic to give the social contribution with management of social facilities. And subway station has to be made conveniently so that everyone may use the station with one-stop system including sales, business, service equipment. This study will show the improvement plan of problem in underground space and situation of metropolitan-train history to improve metropolitan-train station .we will study a traffic line and equipment relocation of underground space considering safety by choosing the improved station and problems of the underground station in seoul. And then we will study the improvement plan of air purification and sound isolation to upgrade service in citizens.
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고속철도 서비스 수혜지역의 확대 요구에도 불구하고, 현재 국가 철도망 관련 상위계획 상에서 제시된 장래 국가 철도망은 수송애로구간 및 수송수요 분석에 의한 개략적인 노선계획이라 할 수 있으며, 합리적이고 장기적인 국가 고속철도망 구축방향은 마련되어 있지 않은 상황이다. 더욱이 기존 철도망의 투자우선순위 평가항목은 경제적 타당성 및 수송수요 규모 등으로 대표되는 투자 효율성, 기존 철도망과 연계될 수 있는 네트워크 연결성, 정책적 타당성으로 획일화 되어 있으며, 이중 대부분의 철도망 계획에 가장 큰 영향을 미치는 항목은 B/C 비율로 대표되는 투자 효율성 측면이라 할 수 있다. 이에 본 연구는 우리나라의 중장기적 고속철도망 계획과 투자우선순위를 전통적인 평가기법에서 벗어나 지속가능한 교통(sustainable transportation)의 관점에서 이를 분석할 수 있는 방법론을 제안하는데 그 목적이 있다. 본 연구는 먼저 지속가능한 교통에 대한 정의를 내리고, 이를 측정할 수 있는 지속가능한 교통 지표를 교통 효과성 지표, 환경지표, 경제지표 및 사회지표로 제시한 다음 지속가능한 고속철도망 평가를 위한 목표와 성과 척도를 선정하였다. 그리고 지속가능한 교통의 관점에서 우리나라 고속철도망의 계획과 투자우선순위를 분석할 수 있는 다원-속성 효용이론(multi-attribute utility theory)을 이용한 다원-기준 의사결정방법론을 제안하였다.
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This study propose a model for railway safety evaluation with which the safety of whole railway system can be evaluated. The evaluation model is to generate a safety index which quantitatively represent the degree of railway safety. Safety index is proposed a function of three indexes; an accident index, safety management index, and safety culture index. This paper describes the first result from the study on the safety target which will be a key starting point toward the development of safety evaluation model. It is recommended that the safety target be composed of several sub-targets that are apportioned to constituent components. It is concluded that the classification of safety target influence on deciding components or attributes that constitute each sub-indexes; an accident index, safety management index, and safety culture index. Based on this study, a railway safety evaluation model will be developed in the next study.
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In light of the growing traffic congestion problem and congestion cost, the container transport by railway has to be increased. The freight transport by railway can have decided advantages over trucks in terms of energy efficiency, emissions and cost for certain freight movements, just as transportation in the metropolitan region can have great advantages over driving truck. But the freight transport by truck should gain significant mobility benefits from a freight railway system. Thus, the DMT(Dual Mode Trailer) transport system which is coupled railway transport advantages with load transport advantages has been developed and used in the european countries. The DMT transport will therefore serve the areas required by transport organizers. This paper describes the various DMT transport systems and its strength and weakness.
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This paper presents an criterion of revenue and cost allotment on the basis of the activity based costing system for a loss-making railroad lines, and presents some ways for effective cost reductions focused on expensive resources and consumption
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Urban has been operating Korail and the local autonomous entity in Korea. Over 70 LRTs will be constructed in the future, but it is hard to manage them due to structural deficit from construction debt, so Public finance plays a very important role in order to overcome a deficit. Therefore, it is necessary to plan detailed analysis and planned system about the expenditure of the amount which is borrowed from country and local government and business income from railroad companies like government grants, PSO. This research wishes to grasp the problem and present model about reasonable and efficient financial program, analyzing about increasing import and expenses of Urban.
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This study is to estimate economic benefits of Standardization R&D of Urban Rail System. Benefit was to be realized through standardization of main areas such as train vehicle, railway, power system, and signal system. To derive and calculate the quantitative benefit, the sources of economic impact was divided into three dimensions -operational cost savings, import substitution, and safety effects. Economic effect of the standardization was categorized based on a modified BSC model. Economic benefits from time and labor savings are converted into cost savings. Import substitution and investment multiplier effect have a positive impact in addition to cost savings. The estimation of the standardization R&D of Urban Rail System was conservatively estimated 370 billion Won. Cost effectiveness of standardized safety system was conservatively translated into economic benefit in this analysis. This study provides a practical guide to economic evaluation of the various railway R&D projects.
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The purpose of this study is to analyze traits of transport goods by Rail. Now, many kinds of shipper transports their goods by the Rail. but Rail transport system did not satisfied their requirements. In order to analyze shippers desire, make a marketing strategy for more efficient rail transportation system, make up a questionnaire on transport by rail and analyze by using AHP method.
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According to the result of recent studies, it was revealed that the error of safety-related personnel still plays a significant role in the accidents and/or incidents of a railway system. Accordingly, in order to reduce as well as prevent human errors, it is necessary to: (1) identify the root cause of accidents/incidents, and (2) conduct a research that can provide a systematic as well as an effective way to deal with the identified human errors. To this end, it is essential to suggest appropriate countermeasures based on the result of a task load analysis, which can soundly reduce a high level of the task load put on safety-related personnel. In the light of this concern, about the tasks of railway traffic signallers, a detailed task analysis was conducted in this study. After that, the associated task load scores were quantified by NASA-TLX technique that is one of the most well-known subjective workload measurement techniques. As a result, a set of significant tasks that could put a high task load on railway traffic signallers was identified.
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차량운용문제 혹은 열차반복문제는 수송계획, 열차운행계획에서 작성된 열차운행시각에 기초하여 편성유형 또는 차종에 따라 주어진 제약조건(선회조건, 검수조건, 기지복귀조건 등)을 반영하여 최적의 차량운용 다이아, 운용순서를 구성하는 문제이다. 일반적으로 이 문제는 집합분할(Set Partition)문제로 모델링하여 열생성(Column Generation) 기법을 사용하여 제약조건에 맞는 운용을 생성하였다. 하지만, 본 연구에서는 지하철과 같이 열차운행의 빈도는 높고 물리적 네트웍은 간단하며 시종착역의 수가 적을 경우 많은 대안 경로(Alternative Routing)들이 생성되는 특징 및 일반 철도와는 다른 역에서의 공간적 제약에 따른 차량 선회 제약을 고려하여 차량운용수를 최소화할 수 있는 지하철 차량운용 문제에 대한 수학적인 모델을 제시하고자 한다. 먼저, 차량선회제약만을 고려하여 최소비용 흐름 모형으로 네트워크 모형을 구성하였다. 최소비용 흐름 모형을 결과로 생성된 운용을 바탕으로 각 운용의 운행거리를 정규화(Normalize)하는 휴리스틱 기법을 제안하였다. 또한, 이 방법론을 실제와 유사한 지하철 열차 스케줄에 적용하였고 약 14%의 차량소요 감소 및 최대 영업거리 약 11%, 표준영업거리편차 약 5% 감소를 통하여 본 연구결과의 유용성을 확인하였다.
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The newly established high speed railway station may function not only just as a traffic convergence but also as an energizing force with multiple roles in the context of municipal environment. As a result, the development of high speed railway station zone will be considered as great opportunities as well to enhance quality of life of the neighboring inhabitants, as to develop new footholds for the inner-municipal growth and mobilization. The main purpose of this article is to offer guidelines about the effects of development of the high speed railway station zone seen from multiple aspects of municipal lifes and functions. To attain this purpose, the definition of high speed railway station zone, its characteristics, and its roles will be handled with the case of advanced countries such as Japan and France. And some lessons will be proposed based on them.
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This study intended to identify the problems of the railroad which are raised as one of the 21C next-generation but to define the direction for the absence of the national policy and examine the competitiveness of railway transportation which is a Green Network with low environmental destruction and high energy efficiency as the continuable means of transportation for the 21st century with superiority to energy crisis caused by high oil price, conclusion of the Kyoto Protocol for worsened air pollution, and reduced cost of traffic jam.
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급격한 변화환경에 직면하고 있는 조직이 이 같은 상황에 능동적으로 대처하면서 조직의 효과성을 증대시키기 위해서는 시장의 변화는 물론이고 조직의 급속한 성장에 부합할 수 있도록 조직의 비전(Vision), 미션(Mission), 가치(Value)를 바탕으로 도출된 경영전략을 토대로 효율적인 경영시스템을 구축할 필요가 있다. 이런 맥락에서 '과거-현재-미래' 라는 시간적 차이(Gap)를 극복하고 효율적 관리체계와 구성원의 직무만족도 및 몰입도 증진을 모색하는 과정에서 적지 않은 업체들이 목표에 의한 관리 시스템(MBO)을 도입하는 경향이 있었다. 본 연구는 철도 관련 조직에서 도입, 운영되고 있는 목표관리제(MBO)가 해당 조직에 어떤 영향을 주는지에 대한 분석을 행하는데 목적을 두었다. 이를 위해 목표에 의한 관리 시스템 도입, 활용하고 있는 철도 관련 조직을 대상으로 목표관리제도와 관련한 다양한 측면의 의견과 만족도를 측정하기 위해 설문조사를 행하였고, 회수된 설문지를 토대로 SPSS 통계 분석을 수행했다. 그리고 이 같은 분석을 토대로 조직의 목표관리제 운영이 효과성을 얻기 위해서는 어떤 요소를 고려해야 하는지에 관한 시사점을 도출하였다.
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This paper suggests a new Level of Service (LOS) for a pedestrian facility in a transportation transfer center. They include the road, stair, and waiting place for a pedestrian. A current situation of several pedestrian facility was surveyed for the existing transportation transfer center at both Seoul and Pusan metropolitan cities. A new LOS was developed based on the output according to foreign criteria as well as an interview of pedestrians for their satisfaction.
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Since July in 2004, starting with urban bus reorganization of Seoul metropolitan government, the change of the public transportation which integrates the urban bus and the subway of the metropolis are being continued. But the integration of such bus and the subway is staying to only a fare system mainly, and the guidance system of the subway and the bus has not changed. So we propose the concept of the new guidance system following public transportation change tendency. At first we introduce the new information system which can guide city railroad and bus altogether, and we propose new system which can guide divided by the trunk line and the branch line instead of bus and subway. Last high-functional guidance system which can give passengers tip and hint for various and effective usage of public transportation in more complicated city transit network is introduced. This new guidance system can increase competitiveness of public transportation system and stretch transportation share of it. And that guidance system is high-class contents that all public transportation business can utilize, so it can originate new industry. In conclusion, this new innovative guidance system is important field that government, local administration and public transportation business must be concerned and develop.
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The purpose of this study is to analyze human safety culture of the railway driver in domestic railway industry. This study proposes safety culture improvement of domestic railway by intensively comparing railway safety system overseas to reinforce domestic railway safety. Domestic railways well known the well-organized railway safety culture has brought up safety issues on their process of private management. With this process, also, domestic safety culture is requested by increasing sense of the safety for general public. This study expects Korean railways to become a well-organized that as removing insecure factors of domestic railway based on result comparing and analyzing the manual, factors and requirements of guideline for internal and external safety culture.
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The objectives of this paper are to introduce the PI(Public Involvement) in railway project and case study about public participation in decision making process for Ko-Yang light rail line development, besides to emphasize the importance of information considering the difference of resident location, regional character and so on are investigated before and after public participation. As the results, it was clarified about PI activities styles that consensus is not achieved in Ko-Yang public participation, the psychological factor such as the knowledge and satisfaction, receptivity about light rail project strongly is affected to making decision.
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Recently, started to apply a strategy of selection and concentration in the construction and transportation R&D for the effective utilization of limited R&D resources. The department of construction and transportation planned the construction and transportation R&D innovative road map by the future 10 years technical requirement under the first year on the innovation of the construction and transportation technology from last year. The innovative road map which is a strategic and long term master plan integrated a construction and transportation suggested a vision as value createar for a improvement of living quality in the future. And made a specific goal that is the seventh construction technology level and the fifth transportation technology level in the world. The department of construction and transportation is planning a mid- long range planing of the construction and transportation R&D as following measurement of innovative road map. KICTEP and KISTEP planned a mid- long range R&D planing of the transportation system, logistics, aviation, railway for the last year. Introducing a methodology used a mid- long range plan and main results of the future railway R&D plan. And suggesting a politic comments for the effectively propelling railway R&D projects.
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In this study, we have studied rail infrastructure related to emergency action to manage the risk when emergency caused by faults of facility or rail vehicle during operation happens. Especially we have compared the effect of emergency action with examining the structure of vehicle, tunnel, bridge and access road, etc which are related to emergency action. Also, we have tried to analyze effects of radio and communication equipment, lifesaving and refuge which could be used for rolling stock, station, control room, tunnel, bridge and etc, and we have presented the way of reporting the emergency to the train driver or crew, control room, outside networks which could be used by passengers in vehicle, station, railroad line. Based on these, we have analyzed the conduct of emergency action in length of time when emergency happens in railway and high-speed railway, and studied the method of which passengers could be guided safely and escape from the scene of the accident.
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Since standardization project is composed of complicate system, such as vehicle, signal, electric power and railway, how to build management system of the project has influence on the success of the project for the first stage of the project. The computer system design tool supports to carry out requirement analysis, DB construction, and history and follow-up management efficiently. Therefore, the aim of this study is to investigate the method to optimize schema using computer system design tool.
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The purpose of research will establish the foundation to enhance the skills of Railway Color Design in the future by accurately analysing the Railway Color characteristics. The emotion and demnds of times influences trend of Railway Color Design, the contents of this research also reflects trend in society and culture. The research contains the history of Railway Design and advance research of Railway Color trend especially influenced by society and culture in the from the 1960's to the year 2005. The study is based on the concept of Railway Color Design. it analyzed the related current of society, culture and Railway Color. Collected Railway Color samples(Railway 46 images) were studied by using visual sensation. The Munsell Color System was used as references. This research analyzed railway introduced as railway models by top 4 nation (United Kingdom, Germany, France, Japan) and Korea in the past years(1960-2005) for their Railway Color Design trend by Munsell Color System. Although the Railway industry has rapidly risen according to life style in society and culture, there has been a lack of organized data for Railway Color Planing. this research on the basis will offer the significant information for Railway Color Design.
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The purpose of this paper describes the changes of TGV & ICE series' nose shape by increasing train speed and according to the periodical characteristics. As the speed increases, the length of the nose shape trends to lengthen longer. But the nose shape length does not increase as speed improves by optimized nose shape to reduce aerodynamic drag and micro-pressure wave in tunnels. TGV & ICE series' nose shape can be classified into Advanced paraboloid type, Shape-nosed type, Organic double-edged type and Flat-nosed type by the advance research(the changes of Shinkansen vehicle' nose shape) of high speed railway. Because it trends to be diversified and characterized more and more. This paper analyzed and introduced as TGV & ICE series' nose shape by top 2 nation (Germany, France) and high speed railway in the past years(1980-2007) for their railway design trends by new positioning(Advance research).
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As the preservation law of soil environment has reinforced, several soil remediation projects have been performing for railroad sites. One of the main sources of soil contamination is the leakage of diesel from locomotives or underground storage tank. Also, the lubricant used to maintain turnouts causes railroad soil contamination. The purpose of this study was to develop the analysis and the remediation method for lubricant-contaminated soil. The lubricant in the contaminated soil was analyzed qualitatively and quantitatively by TLC (Thin Layer Chromatography) and GC (Gas Chromatography), respectively. The organic pollutants were removed from the soil using microorganisms degrading lubricant. Hereafter it will be necessary to apply this bioremediation method in the railroad field.
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According to the Railroad Safety Act and section 42 of the Enforcement Ordinance, railway operators should conduct railway safety training regularly(6 or 3 hours per three months). But Overall Railroad Safety Audit conducted 2006 pointed out nonfulfillment of a regulations on railway worker's safety training to each of every 4 railway operators, which proved that the training management had not carried out properly. E-learning is used in various fields with development of Internet and IT technologies. It might be a good alternative tool for railway workers who is in shift working of the company 24 hours a day. Because it is difficult to collect those employees for training, e-learning could overcome obstacles of time and distance. In order to find out suitable e-learning model to railway sector, e-learning system for railway safety training has been researched through investigating e-learning technology and present railway safety training condition.
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지하철 초기 도입 후 한국형 표준전동차 생산단계까지 눈부신 발전을 하였으나 철도법을 알지 못하거나 관계자이 아닌 기술자가 전동차 디자인을 하여 아쉬운 점이 남는다. 앞으로 도입하는 첨단기술과 열정으로 이룬 전기동차(이하 전동차), 수십 대의 전동차를 동시에 여객 영업운전은 안전운행을 위한 열차운영내규에 맞추어야 하는 등 까다로운 점이 있고, 이것에 대한 면밀한 검토가 있어야 한다. 기존 전동차는 자동차처럼 메이커에 따라 비슷한 것과 종류와 특성이 조금씩 다르고, 그중 가장 보유량수가 많고, 높은 비중을 차지하고 있는 영국에서 기술 도입하여 대우에서 만든 GEC전동차의 전동차 순기능 대책강화방안을 논하고자 한다.
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Railway systems are one of the best mass transit systems and many people have prevented incidents/accidents and reduced fatalities remarkably. Especially we have tried analyzing and finding the measures to prevent catastrophic accidents like train collision, derailment and fire because of their severities. It is important to assess the safety performances of railway systems like crash-worthiness analysis, body, derailment affecting factor analysis and so on for reducing and finding out the reasonable causes of disastrous accidents. In this paper the refined top-level system requirements to build-up national infra for assessing railway safety performance and the procedures and methodology for reviewing, verifying and validating infra requirements are explained. Basically the authors have used system engineering processes to analyze and verify the requirements and installation procedures and have tried maximizing the practicality of the various safety assessment systems.
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The inspection periods for the metro EMU maintenances vary variously according to the countries and railway operators. And the inspection systems vary according to the safety, economical, technical aspects, and also the social environments like passengers and maintenance qualities, etc. Also, in economic point of view, maintenance requires the man power, facilities, equipments, purchasing of parts and the loss of not being in revenue service during the maintenance period. Recently, there is a tendency that the inspection periods are extended gradually owing to the increased reliabilities of the equipments and parts of EMUs. Even if it is the EMUs that are already be in service, once the inspection method is innovated, the inspection time can be reduced. The inspection management innovation scheme includes such methods as the complete module to module replacement when trouble shooting a faulty parts before putting the EMU back to revenue service, the replacements of parts in complete set unit for the heavy maintenance, the establishments of exchange periods for the wasting parts, modernization of inspection equipments, introduction of RAMS for the reliability improvement and computerization of EMU maintenance management, etc. I think it is possible to optimize the inspection scopes and periods per parts and equipments by the introduction of RAMS.
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To establish the national railway safety system, the railway total safety technology development project has been promoted by Ministry of Construction and Transportation (MOCT) since August 2004. The project has producted successful results in many areas of railway safety, however, it is required that the research field should be re-examined to meet the aim of the project. To do that, the precedence of the investment of research resources should be reviewed and determined. The risk of serious railway accidents such as train collision, derailment and level crossing accidents are estimated. From the estimation result and the statistics on the railway accidents over fast few years, the risk factors of railway accidents can be calculated.
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The Yongsan International Business District development work is a 20 billion$ project to raise facilities for national business, trade, residence, and culture. The project site is
$566,800m^2$ and it covers the railroad maintenance center and Dongbuichon-dong. Developing railroad station region used to be done by private investment. However, problems existed; simple function as a massive selling market, traffic jam caused by massive market users, inadequacy to transfer to other transportations, interruption of the pedestrian way and separation of zone of life by the station. To solve this problem it is important to consider developing cases of other countries and devise a plan that is applicable to our circumstances. In the study, we compared our station development case with foreign station development cases and analyze the element for the plan what we should consider in our station development. In addition, The results of the study can be used as a preliminary data in the future planning the Yongsan International Business District development. -
With a land area of 910,768 sq. km, population estimate of 150 million people and GDP-growth rate of 6.9% per annum (2006 est), the centrality of effective public transportation in Nigeria is readily seen. In this regard, rail transportation offers much potential because of its relative safety, reliability, lower cost to the users and being singularly capable of transforming the national economy through mass movement of people, goods and services. Within this context, the demand for an effective railway system, and the enormous potentials for profitable investment in rail infrastructure in Nigeria, is indisputable. Beginning with the history, the paper discusses the main problems of Nigeria's railway transport system; and then makes policy suggestions, after considering the potentials of rebuilding the rail infrastructure. The necessity of this work is premised on the fact that there is a significant gap in critical knowledge about Nigeria's railway transport system.
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Starting her business operation on January 5 2007, Taiwan High Speed Rail (THSR) shapes a new time-space frame for Taiwan western corridor, where more than 90% of national population lives around and more than 95% gross domestic product created from. Comparing with the four-hour traveling time by highway before 2007, THSR reduces the time required to one and half hours from Taipei to Kaohsiung. It will not only benefit the communication along the island from north to south, but also change the location advantages/disadvantages for all cities in these regions. Therefore, this paper establishes a spatial computable general equilibrium model (SCGE Model) to simulate the economic effect of High Speed Rail (HSR). This SCGE model divides Taiwan economy into fifteen geographic regions and thirteen industries. Each region has three sectors: household sector, transportation sector, and industries sector. Following the behavior function of economic theories, the general equilibrium can be achieved simultaneously. Thus, gross regional product (GRP), capital formation, employment income and welfare/utility level can be all observed by calculating the different economic result between cases with-/ without-HSR. Besides, this model presents the social welfare benefit from HSR operation, the polarization phenomenon among regions and within certain region, unbalance distribution of welfare along the HSR line, and industries development divergence among regions etc. These major findings should be useful for regional development policy making.
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Substantive provisions of the concept of an estimation and safety of complex technical systems are envisaged. New problems are assume orientation to use of the formalized methods of an estimation of residual resources of reliability of objects, and also development of other methodological base in creation of complex technical systems that is connected with detailed elaboration of attention to a safety at all stages of creation of systems: from designing until operation. In this connection existing large objects should be provided by the developed systems of engineering monitoring and diagnostics.
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Features of procedures of dynamic synthesis are considered at use of various interpretations or models of processes in mechanical oscillatory systems. Methodological bases for research of the wave processes develop, allowing receiving some features of distribution of indignations. Authors offer scientifically-methodical bases for the decisions received analytical by.
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The wheelsets are one of most important component: damages in wheel tread and press fitted axle are a significant cost for railway industry. Since failure in railway wheelset can cause a disaster, regular inspection of defects in wheels and axles are mandatory. Ultrasonic testing, acoustic emission and eddy current testing method and so on regularly check railway wheelset in service. However, it is difficult to use this method because of its high viscosity and because its sensitivity is affected by temperature. Also, due to noise echoes it is difficult to detect defects initiation clearly with ultrasonic testing. It is necessary to develop a non-destructive technique that is superior to conventional NDT techniques in order to ensure the safety of railway wheelset. In the present paper, the new NDT technique is applied to the detection of surface defects for railway wheelset. To detect the defects for railway wheelset, the sensor for defect detection is optimized and the tests are carried out with respect to surface and internal defects each other. The results show that the surface crack depth of 1.5 mm in press fitted axle and internal crack in wheel could be detected by using the new method. The ICFPD method is useful to detect the defect that initiated in the tread of railway wheelset.
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Switch rail is a very important part on the railway track, which not only accounts for the safety of the passing trains but also greatly influences the speed of the train. The higher the speed and the loads of the train the more it demands on the properties of the switch rail. Research shows that the higher mechanical properties of switch rail the longer the service life. Induction heat treatment is a good way of improving the mechanical properties of metallic materials. But the switch rail's section area changes gradually across the lengthways, which is difficult for induction heating especially for the small section. And the mechanical property of small section of the switch rail is the most important for its service life. The induction heat treatment used past always brings the low hardness on small section which can cause low service life of switch for wearing, or too high hardness because of martensite microstructure which can cause the shelling or even breaking of the switch rail. To prolong the service life of switch rail by higher mechanical properties, we researched the improved induction heat treatment for switch rail by adjusting speed of heating, and adopting compressed air cooling. The results showed that switch rail obtain almost the same high hardness across the length way after the improved induction heat treatment, which is very helpful to extend the service life of switch rail.
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This research attempts to examine the effects of import penetration in an industry on the firms' decision of business diversification and provide an integrative framework including the determinants and results of the business diversification. The research results are as follows. First, the import penetration doesn't affect the degree of business diversification. Second, the more profitable their core business industry, the lower the degree of business diversification against the import penetration. In addition, both technology-related assets and marketing-related assets are necessary for business diversification when faced with the import penetration. Finally, the inverted U-shaped relationship is supported between the degree of business diversification and firm performance.