• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2010년도 춘계학술대회 논문집
• /
• pp.664-670
• /
• 2010

The study on mechanical behavior of the structure at the site includes experimental method and numerical analysis method. Experimental method is categorized into true-scale test and laboratory model test. A laboratory model test is to monitor the failure mechanism with a model simulated similar with a real ground so as to identify the quantitative result, while a true-scale model test is the approach which enables to identify the potential problems that may occur with a simulated construction situation similar with a real site circumstance. Thus this study was intended to carry out the experimental test of non open-cut excavation by pipe roof method which is mostly common in domestic sites. as well as was aimed at identifying the ground behavior occurred during pipe penetration using laboratory model test. Appropriate reduced-scale model was selected, taking into account of domestic geological characteristics and operation characteristics of traditional and high-speed rail trains and the qualitative evaluation of displacement was carried out based on a certain ground loss volume depending on excavation after categorizing trackbed settlement pattern by depth of top soil.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2010년도 춘계학술대회 논문집
• /
• pp.2319-2344
• /
• 2010

Accumulated deficits resulting from managing the Korean Railroad and debts from the construction of the KTX (Korea Train Express which is a high-speed rail system) have left the Korean Railroad faced with great troubles. Since it changed into a public corporation Korail on January 1st, 2005, the Korea Railroad has been making unceasing efforts to overcome the troubles and improve its management. However, even these efforts haven't worked in the face of the improved conditions of other transportation methods such as better networks of land roads and air ways. The Korea Railroad had its revenue from its railway transportation limited, and has tried to expand its business to non-transportational areas. In some metropolitan cities, the Korea Railroad made investments in real estate by constructing station buildings based on private money. Yet, in small and medium size cities, the Korea Railroad has little particular strategic projects for business development. Recently certain small and medium size regional cities began to plan on business developments for the ex-railway land, and some small towns have developed real estate on the ex-railway land. Nevertheless, there have been no systematic case studies to classify these real estate developments.

• 동력기계공학회지
• /
• 제17권2호
• /
• pp.38-45
• /
• 2013

In this study, for carrying out the spray and combustion experiment using a Common Rail Direct Injection(CRDI) system, the controller was fabricated to drive a high speed camera, a injector and a laser beam sequentially at a low cost. CB280 module of one-chip micro processer was used for the controller. In order to confirm responsibility and utility of the controller, the current drive performance, the spray behavior and the injection rate were tested and analyzed under various experimental conditions. As this research results, we found that the fabricated controller was able to control the devices for the spray experiment precisely with the input value in program and it had the dynamic load responsibility and repetition. Also, we found that the injection rates of our experimental results were higher than those of others at the same injection pressure and the controller connected with the laser system and the data acquisition system had validity for carrying out the spray visualization experiment.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1579-1580
• /
• 2015

철도차량의 동력원은 화석연료를 사용하던 디젤차량에서 최근 고속전철 및 도시철도차량, 경량전철 등 전기를 주 동력원으로 사용되고 있다. 철도차량에 전기를 공급하는 시스템은 일반적으로 개활지 등 지상구간에 적용되고 있는 가공전차선 방식과 지하구간, 터널 등에 적용되고 있는 강체가선방식 그리고 경량전철 등에 채용되고 있는 제 3궤조방식이 있다. 최근에는 일반적으로 지하구간의 가선시스템에 적용되던 T-Bar방식의 강체가선 방식에서 탈피하여 고속주행이 가능한 R-Bar방식의 강체가선 방식에 대한 연구가 많이 이루어지고 있다. 최근까지 지하구간의 터널구조에서 강체전차선로를 급전시스템으로 채택할 경우 열차의 최고속도는 국내의 경우 90km/h, 국외의 경우 160km/h를 넘지 못하는 실정이었다. 그러나 이를 극복한 제품이 개발되어 열차운행 최고속도를 200~250km/h까지 향상시킬 수 있게 되었다. 본 논문에서는 최근 설계속도 250km/h 급 R-bar방식 강체전차선로 인터페이스를 위한 이선현상 모의 시뮬레이터 개념 설계에 관한 연구를 수행하였다. 이를 위해 집전성능과 관계가 있는 전기철도차량 이선현상 요인 및 영향 분석하였으며 강체전차선로 운행에 따른 이선 등으로 인한 영향을 고찰하기 위해 이선 현상 모의 시뮬레이터 개념 설계에 대한 연구를 수행하였다.

• 한국소음진동공학회논문집
• /
• 제14권10호
• /
• pp.962-967
• /
• 2004

A bogie is the device that connects a car body and wheel sets of a rail vehicle. It is the critical component that determine:; the running safety, The bogie consists of a frame, suspensions, brakes and wheel sets. Various analyses including a numerical simulation using a finite element method, a static load test, a fatigue test, ai)d r running test should be carried out to design the bogie. However cracks have been found at some end beams of the bogies mounted on the freight cars running with the high speed. The cracks of the end beam results in deterioration of the brake performance an the running safety, A new design has been suggested to solve this problem by ROTEM company and it's performance has been tested in this paper. Numerical simulations and dynamic tests are carried out to figure out the causes of cracks in the conventional bogie, and the vibrational characteristics of the improved bogie are compared with those of the conventional one.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 추계학술대회 논문집
• /
• pp.812-817
• /
• 2004

Recently drastic improvement of railway technology has been accompanied by the construction of very high-speed tracks. It should be noticed that Continuously Welded Rail(CWR) has played significant role in technical development of railway and that installation of CWR is now being scheduled on existing lines as well as newly-built lines. In general, interaction between CWR and bridge deck takes place on bridge section and additional axial force and displacement is to be developed owing to temperature and braking/acceleration forces. This interaction is known to be mainly governed by span organizations and arrangements of foot bearings. In common practice, movable bearing is stationed and designed on the assumption that it is not able to transfer the horizontal force of upper decks. However, it is well known that horizontal resistance is developed in movable bearings due to friction and that friction coefficient of movable bearing is ranged from 0.03 to 0.20 depending on the material of bearings and magnitude of reactions. Therefore, it is easily reasoned out that friction of movable bearing can influence the mutual behavior of CWR and bridge decks. Suggested in this study is to investigate the validity and efficiency of friction effect of movable bearings in controlling the axial force and displacement of CWR on continuous railway bridges.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 추계학술대회 논문집
• /
• pp.250-257
• /
• 2004

Typical railway systems are composed of the various sub-systems, such as tracks, structures, electricity supplying systems, signal systems and vehicles. The roles of the sub-systems are clarified in the railway regulations in terms of their whole life cycle, as like design, operation and disposal stages. The regulations express clearly the basic specifications and requirements that need to accomplish their own performance and also state the standards and procedures for the normal operations and emergency conditions. In this paper the current railway regulation systems are analyzed and average revision periods are presented as the results of the analysis on revision history of railway safety regulations. This paper also presents the requirements for national safety standards based on Railway Safety Act and the necessity of application of system computer aided system engineering (CASE) tool for the improvement of legislation tasks. By exemplifying the cases of high speed rail system and Japanese cases that had developed softwares for supporing regulation revision management, the methodologies was studied for reconstruction of railway safety regulation system. As the results, it was presented such as the considerations for actual implementation and systematic safety regulation revision.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 추계학술대회 논문집
• /
• pp.1229-1234
• /
• 2005

Since the 20th century, the business of railway was invaded by the invention of airplanes and vehicles in the field of the transportation of passenger and commercial products, however, in the 21st century, the fervent development of a high speed railway made possible the huge capacity of transporting passengers and commercial freight, so the railway industry is facing a new era of railway revolution. The 200 years old railway tradition includes the history of railway bridges built in areas of river, valley and metropolitan region and in that, the number of constructions of railway bridges that is composed of cable-stayed bridges is increasing as one of the most optimal bridges considering the quality of materials and the span of continuous-welded long rail. Thanks to the minimized effects of the fixed load on the stiffening girder section by delivering the fixed load which is applied to the pylon with the composition of elastic supporting points by using cables and the effective structural system that can throughly resist extra loads in addition to fixed load, the long-extended span of a bridge becomes possible. In this structural system, the load that is applied to the stiffening girder section forms a now pattern and in the process of these load delivery, there will be a necessity to examine the concentration of stress occurred in the cable-anchor system of the cable.

• 한국철도학회논문집
• /
• 제16권2호
• /
• pp.117-121
• /
• 2013

철도선로구간의 노후도는 궤도, 노반, 교량, 터널 등 요소시설의 노후도로 결정되며 궤도의 선형 또한 선로구간 노후도에 영향을 준다. 본 논문에서는 계층구조분석(analytic hierarchy process: AHP)과 자료포락분석(data envelopment analysis: DEA)을 활용하여 선로구간의 노후도를 평가하는 방법을 제시한다. AHP는 다수의 전문가들이 평가하는 각 요소시설의 중요도를 체계적으로 파악할 수 있도록 해준다. 요소시설에 대한 중요도는 전문가에 따라 달라질 수 있다. DEA는 선로구간 요소시설의 중요도 가중치 범위를 체계적으로 반영하여 선로구간의 노후도를 평가할 수 있도록 해준다.

• 한국분무공학회지
• /
• 제16권3호
• /
• pp.134-139
• /
• 2011

Recent research has focused on engine combustion technology as well as application of after-treatment in order to comply with emission regulation. However, it is much more efficient way to control emissions from engine itself and furthermore research on engine control will provide the direction of after-treatment technology in future. Furthermore, emission standard regulation for passenger diesel vehicles has been stringent compared to others and nano-particles will be included in EURO6 regulation in Europe and similar emission standard will be introduced in Korea. A 3.0 liter high speed diesel engine equipped with by CRDI system of 160MPa injection pressure, and an intake/exhaust system of V type 6 cylinder turbo-intercooler was applied. The injection duration and injection quantity, pilot injection types which are related to CRDI and air/fuel ratio control applied by EVGT were changed simultaneously. Standard experiment procedure constituted dilution apparatus and CPC system to collect nano-particles and these test results were compared with regulated materials of CO, HC, NOx and investigated their relations and characteristics of nano-particles.