• Journal of the Korean Society for Railway
• /
• v.18 no.5
• /
• pp.419-425
• /
• 2015

When a train is delayed because of a disturbance, the time interval between successive trains increases and high-frequency metro lines can become unstable. Time interval control is therefore necessary in preventing such instabilities. In this paper, we propose an optimal interval control algorithm that is easy-to-implement and that guarantees system stability. In the proposed method, the controlled trains are determined from the time interval deviations between successive trains; the control algorithm for staying time is designed by use of a discrete traffic model to ensure an optimal time interval between successive trains. The results of a computer simulation are also given to demonstrate the validity of the proposed algorithm.

• Journal of the Korean Society for Railway
• /
• v.20 no.5
• /
• pp.637-648
• /
• 2017

In this paper, the effects of initial built-in deformation and temperature deformation on the stress distribution of discontinuous precast concrete track slab under train load were examined. According to the results, when train load is put on a precast concrete slab with initial built-in deformation and deformation due to temperature gradient, the maximum tensile stresses develop at the upper side of slab in the slab center, edge center and corner of shear pocket; the stress distribution is different from that of the case under train load only. Therefore, to accurately predict the actual weak points and failure modes, one should calculate the stress under train load considering the initial built-in and temperature deformation of the slab.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.9
• /
• pp.6214-6220
• /
• 2015

A track circuit has used stably more than 100 years for detecting train position, but solution of track circuit sort circuit incapacity due to a rust is necessary for side line in station yard, coast line and level crossing for conventional line in rural line. Domestically, Axle Counter System(ACS) has partially used for Hot Box System for high speed line and turnout for CBTC system. In contrast, most of countries has used ACS not only trunk line but also rural line and its application has increased for metro, electric car and industrial railway. In this paper, we has verified the operating status of ACS which installed with existing track circuit through log analsis to implement pilot application in mail track and turnout in station yard. And interface test with interlocking system has conducted at Obong shunting yard, as well as Cheongju station and has analyzed test result. Based on a test result, we made fail safe design, manufacturing skill and established system requirement specification for the smooth operation and maintenance.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.3
• /
• pp.471-477
• /
• 2013

We have studied on the possibility of precise positioning using hybrid Track Circuit system. Hybrid Track Circuit uses RFID which replaces UHF. Hybrid Track Circuit is a part of next generation railroad signal system which is available to communicate with a railway on board system based on a realtime operating system. If applicate on a current hand operating subway, phenomenon caused by driver's mistake such as passing a stop without stopping or mismatch error between PSD and train door should be prevented.

• Proceedings of the KIEE Conference
• /
• 2009.04a
• /
• pp.195-197
• /
• 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 the Korean Society for Railway
• /
• v.17 no.2
• /
• pp.148-155
• /
• 2014

This practical study investigates the effects of job satisfaction as a result of the stresses felt by many dispatchers who work in the subway industry in the Seoul metropolitan area. Factors that cause stress are assessed. The organization system, inappropriate compensation, workplace culture, and job requirements, among several types of organizational stresses are significantly related to job satisfaction. The results of the analysis indicate that there is a close link between job satisfaction and dispatcher communication factors. This paper suggests stress-relief measures for dispatchers who must handle a variety of civil complaints and improper communications with field departments based on the analysis of the answers to descriptive questionnaire items.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.91-98
• /
• 2009

For maintaining railroad, accumulated passing tonnage is a determinant factor of appropriate rail replacement time. Recently, Seoul Metro's rail maintaining system and technology is being improved from previous years, which increasing a standard of rail replacement. Thus, this brings importance of estimating and managing for accumulated passing tonnage. In case of light weighted train such as subway, current method of calculating accumulated passing tonnage has defaults of misrepresenting accumulated passing tonnage data. Because current method is based on the weight of passengers and train., and operation data. In addition, currently there is no mechanical and electronic system that could represent and support the accurate data between heavy and non-heavy traffic area, and accumulated passing tonnage is calculated inaccurately by estimating average value each line. The current method of calculating accumulated passing tonnage misleads to unpredictable data that represent inappropriate rail replacement period, which leads to under or over analyzed replacement period. If accumulated passing tonnage is over estimated, rail replacement leads to waste of budget. Hence, it is necessary to construct reliable actual measurement system to manage rail's life safely and efficiently, and in this study the accumulated passing tonnage measurement device is installed with using rail pad of optical fiber sensors and its effect is analyzed.

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.964-968
• /
• 2005

The standardization of information communication is doing a Internal each other connection and each other characteristic stability operation security in objective. From the low-speed network of the subway operation beginning currently it changes with the superhigh speed digital information transmission communication service environment which is a quality service, the hazard which plans the quality improvement of the efficient communication service use which hits to here and passenger service the standardization of the technical standard which stands and the improvement which hits to an engineering standard and facility must come to accomplish. The facility which existing is been old or the enclosure communication equipments which are insufficient. it improves, establishment itexpands efficiently, like this facilities it is stabilized and it is economic and rationally use maintenance it manages with the plan for the inside and outside of the country information communication relation technical standard and engineering standard service feature improvement and future expandability and economical efficiency, the possibility of having a pliability in order to be, rational technical standard and standard it takes a triangular position, efficient characteristic security of information communication service there is a place objective which promises the rational development of course city railroad communication system with character. Function improvement of enclosure communication base equipment, against an improvement and standardization plan it described trom the prosecution which it sees.

• Journal of the Korean Society for Railway
• /
• v.14 no.4
• /
• pp.348-353
• /
• 2011

Iron fillings which were accumulated around the rail was often the cause of abnormal signal in case of signaling equipment using rail as transmission line. Iron fillings were generated on curved section of railroad due to the friction between rail and wheel, and metro line company urged to find the way to remove these iron fillings, because these were often the cause of abnormal signal. Magnetic device for trapping iron fillings around concrete slab tracks is introduced. The characteristics of magnetic device were analyzed using basic design and numerical analysis method. Magnetic device for trapping iron fillings were examined for application to the train which were operating in commercial line.

• International journal of advanced smart convergence
• /
• v.12 no.1
• /
• pp.208-219
• /
• 2023

Recently, as mega-urbanization progresses, urban logistics centered on large cities is growing rapidly, and logistics transportation is increasing due to the lack of logistics infrastructure and the operation of a delivery system using cargo trucks in the city center. being cited as a cause. In order to solve this problem, domestic researchers are conducting research on the development of " Urban Underground railway Logistics System" that minimizes the initial infrastructure construction cost by utilizing the existing urban railway facilities in the city. Therefore, this paper analyzed the usage environment of the actual urban railway station to which the system will be applied in order to derive candidates for the test bed selection of "Urban Underground railway Logistics System". The evaluation criteria for test bed candidate role selection were established, and the candidate group derived from the Brown & Gibson model was used to evaluate the candidate group and derive the candidate role. A review of the results was conducted to contribute to the establishment of a test bed for the " Urban Underground railway Logistics System" under development.