• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.1
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• pp.171-175
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• 2015

In this paper, because of global environmental problems such as energy shortage and abnormal climate, green energy development and energy saving technology development is being magnified. Heat insulation, the most basic and traditional energy saving method, is highly expected. Especially, simple and advanced heat insulation technique based on Nano material is promising future technology. The railway system also requires heat insulation. Especially, traditional heat insulator such as glass wool has been adopted frequently to rolling stock. The heat insulator is also adopted in general railway service buildings. Take account of cost-effective heat blocking performance, the heat insulator shall be adopted in diverse fields such as electric power, railroad, signal and communication. The only and direct solution for this problem is installing heat insulator with outstanding endurance, corrosion resistance and heat resistance to block outer heat Upgrading heat specification of equipment can be a solution, but since price and maintenance cost rise severely, this plan might be incongruous. In this research, energy saving effect of ultrathin heat insulator film was demonstrated by installing the film on roof of electrical room.

• International Journal of Railway
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• v.1 no.4
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• pp.149-156
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• 2008

During maintenance or construction works in or at the tracks of railways, high risks for passengers and railway staff, especially for the workers on the construction site exist. The high risks result out of the movement of rail vehicles, like trains or construction vehicles, which must be faced by using any available technical and operational technologies for securing them against the environment. Therefore, it is necessary to evaluate the level of protection continuously and to identify new and innovative methods and technologies for the protection of the gang (construction worker, machines and material). Especially on construction sites at line sections with two or more parallel tracks but also with single tracks, there are still a lot of incidents and accidents mostly with seriously injured persons or fatalities. These were mainly gang members that breach the railway-loading gage. By using proper warning or protection systems, the avoidance of such accidents must be achieved. The latest developments. in gang protection systems concern on the one hand fixed barriers in the middle between the construction site and the operated track and on the other hand construction vehicles equipped with automatic warning systems. The disadvantage of such protection methods is that the gang can be warned against an approaching train but a monitoring of the gang members cannot be performed. Only one part of a potential dangerous situation will be detected. If the gang members will overhear the acoustic warning signal of the security staff and the workers will not leave the danger zone in the track, the driver of the approaching train had no chance to react to the dangerous situation. An accident is often inevitable. While the detection of acoustic warning signals by the gang members working on a construction site is very difficult, the acoustical planning of an automatic warning system has to be designed for an acoustic short range level of one meter besides the construction vehicle. The decision about the use of today's technical warning system (fixed systems, automatic warning systems, etc.) must be geared to the technical feasibility and the level of safety which is needed. Criteria for decision guidance to block a track should be developed by danger estimation and economical variables. To realize the actual jurisdiction and to minimize the hazards of railway operations by the use of construction vehicles near the tracks further developments are needed. This means, that the warning systems have to be enhanced to systems for protection, which monitor the realization of the warning signal as a precondition for giving a movement authority to a train. This method can protect against accidents caused by predictable wrongdoing. The actual state of the art technique of using a collective warning combined with additional security staff is no longer acceptable. Therefore, the Institute of Transportation System of the German Aerospace Center in Braunschweig (Germany) will develop a gang warning and protection system based upon imaging methods, with optical sensors such as video in visible and invisible ranges, radar, laser, and other. The advantage of such a system based on the possibility to monitor both the gang itself and the railway-loading gauge either of the parallel track or of the same track still in use. By monitoring both situations, the system will be able to generate a warning message for the approaching train, that there are obstacles in the track, so that the train can be stopped to prevent an accident. And also the gang workers will be warned, while they breach their area.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.38-43
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• 2005

In Korea, as in other developed countries. new urban transportation system development projects are underway through national R&D projects. For its final objectives, it becomes more and more important to put the products of R&D projects in use, with the government policies. In this context, the authors of this article suggest. 1) to define a development system, or favorable environment, adequate for the new urban transportation systems for its application and 2) to complement actual regulations on the new transportation technology and trial running based on the law related to the more efficient transportation system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3D
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• pp.283-289
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• 2012

Because railways themselves are not enough to provide door-to-door service, they need to be complemented by a transportation system access the stations and a convenient transfer system to access other railway lines. User friendly service policies include a faster, interconnected, and intermodal transportation system. It becomes more important to use deep subterranean space from an economical standpoint in order to promote railway construction projects. In this research, the authors dealt with construction plan for strengthening capacity of deep subterranean railways. Since deep subterranean railways are situated deeper underground than other railways, they are more difficult to access and transfer to, in addition to psychological pressure. Moreover, deep subterranean railways with high speed add access difficulties as the distance between stations increases. Therefore, the authors discuss not only systemization for uniting deep subterranean railways and other transportation facilities but also reinforcement strategies. The purpose of these strategies is so that deep subterranean railways provide mobility while established railways provide accessibility to overcome this problem.

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1305-1310
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• 2016

• International Journal of Railway
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• v.5 no.4
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• pp.175-181
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• 2012

This study proposes a model for railway safety assessment with which the safety of whole railway system can be evaluated. The purpose of the assessment model is to generate safety indicators which quantitatively represent the degree of railway safety. Safety indicators were proposed as three indicators according to their functions; accident indicators, safety management indicators, and safety culture indicators. This paper describes the first result on the safety target which will be a key starting point toward the development of safety assessment model. It is recommended that the safety target to be composed of several sub-targets are apportioned to constituent components. It is concluded that the classification of safety target has influence on deciding components or attributes that constitute each sub-indicators; accident indicators, safety management indicators, and safety culture indicators. Based on this study, a railway safety assessment model will be developed in the following study.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.195-197
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• 2009

It is a proven fact with the opening of the Seoul metro line number 1 in 1974 traffic congestion on the roads has decreased and the efficiency of people transportation in general has greatly been enhanced in the downtown and surrounding areas of Seoul. Even today construction of new subway lines are under way and many more are being planned due to the easy access to stations, short waiting and average travel times, compared with personal vehicles, contributing to the efficiency of the public transportation systems that are linking the downtown areas and also the intercity systems in moving passengers during rush hour and times of special event. Since the labour costs of the train operator in any large city based subway system accounts for a major part of the operating costs per kilometer and to ensure cost efficient operations, especially during non-peak hours, it is necessary to implement an unmanned(auto-driven) subway system. In order to implement such a system it is imperative that the on-board and wayside signalling control systems be fully automated as well. Only through proper examination of safety procedures not only by the AUGT(Automated Urban Guided Transport)system but also by ail the international standards organizations involved can safely and stability be ensured.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1320-1327
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• 2017

In this paper, a contact loss simulator for a rigid catenary system was designed and used to analyze the effect on the power source according to the conditions of the rigid catenary system and pantograph. R-bar applied to a high-speed train among the real rigid catenary system was used in the contact loss simulator for rigid catenary systems. The excitation frequency generated with the movement of the railway vehicle was simulated. The characteristics according to the frequency and amplitude of the excitation frequency and the presence or absence of pantograph movement were analyzed. This work is considered to be helpful in analyzing the characteristics of contact loss in the interface between a real rigid catenary system and a rail vehicle.

• Korean System Dynamics Review
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• v.10 no.3
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• pp.5-23
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• 2009

Transportation systems around the world are difficult to maintain sustainability that, in a broad sense, is the capacity to endure. By connecting Entropy theory and systems thinking, we find the current problems and seek alternative plans. Distortions of the current transportation system to improve individual's ease and increasing traffic congestion, impose us the heavy energy consumption and will make increase whole entropy. UNEP reports are presented following three reasons that undermine the sustainabillity. The first one is that the prevalent traffic system highlight benefits of accessibility than benefits of mobility, the second, deteriorate excessive energy consumption, and the last reason is that personal vehicles has inhibited the use of public transportation. Alternative ideas to enhance the sustainable transportation system are these; (1) changeover from 'Ease of movement' to 'space efficiency', (2) evolving the smart traffic system instead of the construction or expansion of the road and (3) creating more comfortable the use of mass transportation. In addition, there are another ways that encouraging modal shift that increase traffic of goods, transport over railway lines and waterways, decongesting transport corridors and elevating technology to improve public transportation. The most importantly, we converse our cognitive process to be willing to enjoy uncomfortable and annoying life.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2303-2308
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• 2010

We studied the cost-volume supply characteristic of public transportation systems focused on Bi-modal Tram in the main cities to analyze the applicability and status for the new transit system Bi-modal Tram as public transportation system. The operation cost considering the characteristic of vehicle, facilities, operation and average cost for respective public transportation system and the time cost considering the travel and transfer time are defined to the social cost, and the cost-volume supply curve is based on this social cost. The cost-volume supply characteristic between public transportation modes in the city is determined on the basis of cost-volume supply curve. Through the comparison between cost-volume supply characteristic of main transportation systems, it is analyzed about the relation between public transportation systems in the city and the characteristic for proper service provision. The application of Bi-modal Tram in the city is concluded that it is effective to reduce the social cost on the existing public transportation system.