• Title/Summary/Keyword: heavy traffic

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Basic Study on Damaged Area Types and Improvement Idea of the National Park (국립공원의 훼손지 유형과 개선방안에 대한 기초적 연구)

  • Yeom, Sung-Jin
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1405-1415
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    • 2015
  • This study is conducted to determine the damage, distinguish the types and identify the restoration by that type for 13 Korea national parks out of 21. There are 21 Korea national parks are in Korea covering 6.67% of the country or $6,656km^2$ ($3,902km^2$ on land and $2,754km^2$ in the sea) currently since the area around Jirisan ($440km^2$) was designated as the first Korea national parks in 1967. With the cancellation of entrance admission on Korea national parks since 2007, annual visitors to the Korea national parks have grown from 37 millions in 2008 to 46 millions by 2013 and continue to grow due to numerous leisure activities, alpine activities and social changes. As such, Korea national parks are natural resource with high value to be conserved and are attracting significant attention as recreational spaces for people at the same time. On the other hand, there have been issues of soil erosions or disturbed vegetation due to increased number of visitor to the national parks. Korea national parks area damage to its type and damage characteristics to analyse the 13 Korea national parks out of 21 on July 2012 March, Korea national parks over the subjects of the National Park from damaged area status Survey analysis by the Korea National Park Service. As a result, 203 million units in the 16 Korea national parks damaged land of the reform package during ecological trail (including non-regular hiking trails) 153 (77.66%), damaged valleys 20(9.14%) independent damaged area, 13 disconnected ecological axis(7.61%), closed trail(2.03%) (3.55%), and line type damage(like a non-regular hiking trails) appears to be a high ratio. Korea national parks damaged land of the results identified, by contrast ratio and the annual number of visitors Bukhansan national park(49.26%), Gyeongju national park(23.65%) damaged land rates, such as Seorasan national park(4.93%), Songnisan national park (4.43 %), Gyeryongsan national park(3.45%), and the annual number of visitors be similar result. The National Park Service has been reporting on damages and restorations but damages and their types have not been established yet. Damages have been generally studied and categorized on hiking trails due caused by heavy traffic on them but the reports were limited on hiking trails only. Since damage to the Korea national parks are not limited on the hiking trails, it is necessary to determine damages in various aspects. Thus, in this study, damage types, spatial characteristics, causes and restorations are analyzed based on the survey results of damages to national parks in order to provide a basis for the efficient management and operation of the Korea national parks.

OD trip matrix estimation from urban link traffic counts (comparison with GA and SAB algorithm) (링크관측교통량을 이용한 도시부 OD 통행행렬 추정 (GA와 SAB 알고리즘의 비교를 중심으로))

  • 백승걸;김현명;임용택;임강원
    • Journal of Korean Society of Transportation
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    • v.18 no.6
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    • pp.89-99
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    • 2000
  • To cope with the limits of conventional O-D trip matrix collecting methods, several approaches have been developed. One of them is bilevel Programming method Proposed by Yang(1995), which uses Sensitivity Analysis Based(SAB) algorithm to solve Generalized Least Square(GLS) problem. However, the SAB a1gorithm has revealed two critical short-comings. The first is that when there exists a significant difference between target O-D matrix and true O-D matrix, SAB algorithm may not produce correct solution. This stems from the heavy dependance on the historical O-D information, in special when gravel Patterns are dramatically changed. The second is the assumption of iterative linear approximation to original Problem. Because of the approximation, SAB algorithm has difficulty in converging to Perfect Stackelberg game condition. So as to avoid the Problems. we need a more robust and stable solution method. The main purpose of this Paper is to show the problem of the dependency of Previous models and to Propose an alternative solution method to handle it. The Problem of O-D matrix estimation is intrinsically nonlinear and nonconvex. thus it has multiple solutions. Therefore it is necessary to require a method for searching globa1 solution. In this paper, we develop a solution algorithm combined with genetic algorithm(GA) , which is widely used as probabilistic global searching method To compare the efficiency of the algorithm, SAB algorithm suggested by Yang et al. (1992,1995) is used. From the results of numerical example, the Proposed algorithm is superior to SAB algorithm irrespective of travel patterns.

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A Study on Activation device of 119 Emergency Care (119구급대의 활성화 방안에 관한 연구)

  • Koh, Jae-Moon;Kim, Gyoung-Wan;Chung, Yong-Tai
    • The Korean Journal of Emergency Medical Services
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    • v.11 no.1
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    • pp.27-40
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    • 2007
  • Even now, 119 rescue services have dissatisfactory aspects in operation, system and equipments as discussed above, It is the most urgent subject to systemize rescue services so that they can be suitable for our status, for we will make 21C welfare state come true before long. So, this author suggest that the followings have to be raised to activate 119 rescue service. 1) Bring up experts and offer high-quality rescue service 2) Prepare more up-to-date equipments 3) Operate transfer joint organizations 4) Promote the ability to meet with a press at the time of rescue service activities 5) Adjust regulations related to rescue services 6) Make up for a countermeasure to traffic accidents of ambulances 7) Adjust regulations making it mandatory to establish heliport at the target on hospitals more than a defined scale 8) Install more rescue service teams 9) Educate and train officials belonging to briefing rooms, where the officials with long experiences are arranged 10) Minimize the time for rescue team to reach fields 11) Establish legal protection system for rescue the team Nowadays, our country operates the department of fire fighting and rescue services without great difficulty, even though the circumstances are bad - insufficient members and the inferior circumstances. All of the fire fighting officials are given heavy duties in bad circumstances, and so are the team of rescue service. The rescue service team, taking charge of some emergency medical system, do a fire fighting inspection as a non-duty service, though they are scanty of sleep due to prevention and protection services of the fire fighting service team. But, they can not engage in rescue services completely and have to deal with miscellaneous duties. So they can not offer professional emergency medical services. But now, almost every fire fighting organization, belonging to National Emergency Management Agency, are separating rescue services, which shows a lot of good results. People recognize rescue services to get better and better gradually and the demands for this rescue services increase. So, this is the best time when rescue service teams should offer qualitative services rather than quantitative services. The people will recognize this rescue service team to be an organization sacrificing and serving for them. However well institutes and operation systems should be established, the rescue service team can not come true their aim without strong wills that they will serve and sacrifice themselves for people from their hearts. In addition, it is essential for the officials in charge of policies about emergency medical services to have a concernment on and practice the policy without failure.

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Automatic Control for Ship Collision Avoidance Support-II (선박충돌회피지원을 위한 자동제어-II)

  • Im, Nam-Kyun
    • Journal of Navigation and Port Research
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    • v.28 no.1
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    • pp.9-16
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    • 2004
  • The purpose of this study is to examine the algorithm of ship collision avoidance system and to improve its performance. The study on the algorithm of ship collision avoidance system have been carried out by many researchers. We can divide the study according to the adopted theory into two category such as 'collision risk calculation method' and 'risk area method'. It is not so difficult to find heir merit and demerit in the respective method. This study suggested newly modified model, which can overcome a limit in the two method. The suggested model is based on collision risk calculation method and suggests how to solve the threshold value problem, that is, one of the unsolved issues in collision risk calculation method. To solve that problem this study proposed new system under which the users can select appropriate threshold value according to environments such as traffic situations and weathers conditions. Simulation results of new model is schematized using 'risk area method'to examine the relationships between the two method. In addition, in case of 'collision risk method', when TCPA and DCPA are used to determine collision risk, a problem happens, that is, two ships become too close in their stem area, therefore, partial function of 'risk area method'is adopted to solve the problem in suggested model.

A Study on the Life Cycle Cost Analysis of Light Railroad Transit Bridges (경량전철 교량의 생애주기비용 분석에 관한 연구)

  • Lee, Du-Heon;Kim, Kyoon-Tai;An, Dong-Geun;Jun, Jin-Taek;Han, Choong-Hee
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2006.11a
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    • pp.384-389
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    • 2006
  • The needs for Light Railroad Transit(LRT) have been increased due to the heavy traffic congestions in large cities like Seoul, Korea. Korean government is seeking the LRT system development (including planning, designing, construction, and maintenance and operations) in terms of public-private-partnership (PPP). At the private sector side, it is crucial to estimate the life cycle cost (LCC) to project the cash flow during the O&M period. Since the most construction and O&M cost of LRT project is at the bridge construction, a cost analysis model and a cost breakdown structures (CBS) on LRT bridges are discussed through in depth literature reviews. Construction and maintenance cost of bridges are collected and analyzed. LCC is analyzed by types of bridge superstructures and historical data of repair and rehabilitation (R&R) is investigated. There have been scarce number of LCC analysis on railway bridges. This research delivers a well-defined CBS and maintenance cost data, which will be a great benefit to the systematic maintenance strategy development for railroad bridges.

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An Experimental Study About a Net-Type External Prestress Strengthening Method for Slab Bridges (네트형 외부 긴장재에 의한 슬래브교 보강 실험)

  • Han, Man Yop;Kang, Tae Heon;Choi, Sok Hwan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.5
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    • pp.136-149
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    • 2011
  • Large portion of the domestic bridges are slab bridges reflecting the geographical characteristic of the country, where exists lots of inclines and small winding brooks. Many of the slab bridges are damaged and superannuated as they become obsolete. Deterioration is accelerated when the traffic density becomes large and heavy vehicles pass frequently. A strengthening method for deteriorated slab bridges was studied in this work. The examined net-type strengthening method uses both longitudinal and transverse prestressing for strengthening. In this way, the deflection at the center of the slab can be better controlled, and consequently, the slab is more efficiently strengthened. Three slab specimens were fabricated for the experimental test and subjected to three different loading conditions, and the load bearing capacities and deflections of slabs were examined. Flexural stiffness of slabs increased by 30.7~107.3%, and deflection of slabs decreased by 27.6~52.2% after net-type strengthening. The net-type prestressing is efficient to the strengthening for the center of a slab, and its efficiency is also valid under eccentric loadings. Since extra prestress forces can be added in the future, if necessary, the net-type strengthening system is advantagous for the maintenance and repair of slab bridges.

Design and Algorithm Implementation of a Distributed Information Retrieval System using Sequential Transferring Method(STM) (순차적 전달방식(STM)을 이용한 분산정보검색시스템의 설계 및 알고리즘 구현)

  • Yoon, Hee-Byung;Kim, Yong-Han;Kim, Hwa-Soo
    • The KIPS Transactions:PartB
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    • v.11B no.5
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    • pp.603-610
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    • 2004
  • The distributed Information Retrieval System centrally controlled by mediator or meta search engine result in congestion of heavy traffic and int he problem of increment of cost for the reason of the design of complicated algorithm for central control and installation of hardware. So to figure out this problem, the way is needed that has independent retrieval functionality and can cooperate each other without dependency. In this paper, we overview a few works involved in distributed information retrieval system, then, implement algorithm and design the frame-work of distributed information retrieval system using sequential transferring method(STM) including multiple information retrieval system separated from central control. For this first of all, we present a web partition policy which devide and manage web logically and we present the sequential query processing way by means of illustration through changing numbered information retrieval system. Then, we also present 3-layered structure of framework and function and module of each layer suitable for information retrieval system. Last of ail, for effective implementation of STM algorithm we analysis module structure and present description of pseudocode of this, and show that the proposed STM algorithm works smoothly by demonstration of sequential query transfer process between servers.

A Moving Object Query Process System for Mobile Recommendation Service (모바일 추천 서비스를 위한 이동 객체 질의 처리 시스템)

  • Park, Jeong-Seok;Shin, Moon-Sun;Ryu, Keun-Ho;Jung, Young-Jin
    • The KIPS Transactions:PartD
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    • v.14D no.7
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    • pp.707-718
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    • 2007
  • Recently, much studies for providing mobile users with suitable and useful content services, LBS(Location Based Service) corresponding to the change of users' location, are actively going on. First and foremost, this is basically owing to the progress of location management technologies such as GPS, mobile communication technology and the spread of personal devices like PDA and the cellular phones. Besides, the research scope of LBS has been changed from vehicle tracking and navigation services to intelligent and personalized services considering the changing information of conditions or environment where the users' are located. For example, it inputs the information such as heavy traffic, pollution, and accidents. The query languages which effectively search the stored vehicle and environment information have been studied depending on the increase of the information utilization. However, most of existing moving object query languages are not enough to provide a recommendation service for a user, because they can not be tested and evaluated in real world and did not consider changed environment information. In order to retrieve not only a vehicle location and environment condition but also use them, we suggest a moving object query language for recommendation service and implement a moving object query process system for supporting a query language. It can process a nearest neighbor query for recommendation service which considers various attributes such as a vehicle's location and direction, environment information. It can be applied to location based service application which utilizes the recommended factors based on environmental conditions.

Development of optimal cross-section design methods for bored utility tunnels: case study of overseas typical cross-sections and design criteria (터널식 공동구 최적단면 설계기술 개발: 해외 표준단면 사례 및 설계기준 분석)

  • Park, Kwang-Joon;Yun, Kyoung-Yeol
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.6
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    • pp.1073-1090
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    • 2018
  • Since the domestic utility tunnels were built mainly in the development project of the new city, they are all in the form of cut-and-cover box tunnel. But, in the case of overseas construction of utility tunnels for existing urban areas, the bored tunnel types are mainly adopted. It is reasonable to install bored tunnels in a downtown area because it is difficult to block the roads or install bypass roads due to heavy traffic and civil complaints. In order to activate the utility tunnels in bored type, it is necessary to secure optimized cross-sectional design technology considering the optimal supplying capacity and mutual influencing factors (Thermal Interference, electrolytic corrosion, efficiency of the maintenance, etc.) of utilities (power cables, telecommunication cables, water pipes, etc.). The optimal cross-section design method for bored utility tunnels is ultimately to derive the optimal arrangement technique for the utilities. In order to develop the design methods, firstly, the cases of tunnel cross-section (Shield TBM, Conventional Tunneling) in overseas shall be investigated to analyze the characteristics of the installation of utilities in the section and installation of auxiliary facilities, It is necessary to sort out and analyze the criteria related to the inner cross-section design (arrangement) presented in the standards and guidelines.

Fire resistance assessment in construction joint of precast fireproof duct slab (프리캐스트 방식 내화풍도슬래브 시공조인트부의 화재저항성능 평가)

  • Choi, Soon-Wook;Kang, Tae-Ho;Lee, Chulho;Kim, Se Kwon;Kim, Tae Kyun;Chang, Soo-Ho
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.5
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    • pp.359-370
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    • 2021
  • Duct slabs, which are used to build ventilation facilities in underground spaces with transverse ventilation system, need to secure fire resistance according to longitudinal and heavy vehicle traffic of tunnels. This study measured the temperature change at the construction joint of the precast fireproof duct slab which integrates fire resistance material and duct slab under the RWS fire scenario. As a result, it was confirmed that if there is no reinforcement of the construction joint, damage will occur in concrete inside the construction joint, leading to damage to the fireproofing layer. On the other hand, when one side of the construction joint was reinforced with fireproofing materials, it showed more than three times the fire resistance performance compared to when there was no reinforcement. At this time, cross-sectional losses of concrete and fireproofing layer were shown in blocks without reinforcement, but no damage was seen in the reinforced blocks.