• Proceedings of the KSR Conference
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• 2011.05a
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• pp.337-342
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• 2011

A roller rig has been widely used in the study about dynamic stability and railway safety. However, the cost for constructing the roller rig and the difficulty in adjusting the design parameters for vehicle systems lead to the development of a small scale simulator which is cheaper than the large scale test systems and easy to control the parameters affecting dynamic characteristics of the railway vehicle. For the operation of the small scale test system called a small scale simulator, it is required to investigate the performance and characteristics of the system. This could be achieved by a comparative study between an analysis and an experiment. This paper presented the analytical model which could be used for verifying of the test results and understanding of the physical behavior of the dynamic system comprising the small scale bogie and the simulator.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1905-1913
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• 2011

The dynamic characteristic of bogie that is driving system of railway vehicle is very important regarding decision of vehicle characteristics as running safety and comport. The dynamic characteristic test of bogie is tested on full size in place on field testing on track. But, the testing on the full size caused many problems. To overcome these problem by full size test, the Railway Safety Research Center in Seoul National University of Science & Technology developed 1/5 scale size of small scale derailment simulator and is currently testing running stability of 1/5 scaled bogie. Also To take effectively advantage of running stability test using small scale derailment simulator in actuality design and reliability estimation, it is necessary comparison and examination with field test and theoretical analysis result In this paper. to achieve running stability analysis of 1/5 scaled bogie on small scale derailment. the program using MATLAB that is fast compose and analysis the motion equation of Saemaul power bogie is developed. It is achieved analysis according to various specification (weight, size, suspension, etc..) and is evaluated corelation between test result and dynamic characteristic of actual railway vehicle.

• International Journal of Railway
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• v.4 no.2
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• pp.50-55
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• 2011

The dynamic stability of railway vehicle has long been one of the important issues in railway safety. The dynamic simulator has been used as a tool for investigating the dynamic stability of railway vehicles and wheel/rail interfaces. In particular, small scale simulators have been widely used in laboratory studies instead of full scale roller rigs which can be quite costly and rather inconvenient for testing out the effect of diverse design parameters. But techniques for design of a small scale simulator for the fundamental study about the dynamic characteristics of the wheel-rail systems and the bogie systems have not been well developed in Korea. Therefore, a research on the development of a small scale simulator for investigating bogie dynamics needs to be undertaken. The present paper investigates design of a small-scaled derailment simulator and the design of a small scale bogie. The simulator developed can be used to investigate the effect of diverse parameters such as attack angle, wheelbase and cant on dynamic behavior of the bogie and key dynamic performance parameters such as derailment coefficient and critical speed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.2
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• pp.325-330
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• 2018

In this paper, we investigated the impedance method for searching fault detection point in case of an accident in the AC electric railway AT feeding system. For this purpose, simulation circuit modeling and prototype hardware are made based on the known numerical analysis. As a result of simulation modeling of the feeding system based on the numerical analysis of the impedance method confirmed that the modeling was properly implemented with an average error rate of 0.07%. Also, as a result of fault event by hardware simulator, it was confirmed that the breaker operation time is shortened and the fault current is decreased while the voltage is close to the supply voltage in the transient state as the point of the fault accident moves away from the substation(SS).

• Journal of the Korean Society for Railway
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• v.15 no.1
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• pp.9-16
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• 2012

The dynamic stability of railway vehicle has been one of the important issues in railway safety. The dynamic simulator has been used in the study about the dynamic stability of railway vehicle and wheel/rail interface optimization. Especially, a small scale simulator has been widely used in the fundamental study in the laboratory instead of full scale roller rig which is not cost effective and inconvenient to achieve diverse design parameters. But the technique for the design of the small scale simulator about the dynamic characteristics of the wheel-rail system and the bogie system has not been well developed in Korea. Therefore, the research using the small-scaled derailment simulator and the 1/5 scaled bogie has been conducted. In this paper, we did running stability test of 1/5 scaled bogie using small-scaled derailment simulator. Also, for the operation of the small scaled simulator, it is required to investigate the performance and characteristics of the simulator system. This could be achieved by a comparative study between an analysis and an experiment. This paper presented the analytical model which could be used for verifying the test results and understanding of the physical behavior of the dynamic system comprising the small- scaled derailment simulator and the 1/5 scaled bogie.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.430-436
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• 2018

Special railway vehicles for track maintenance are equipped with a tamping device that adjusts various track trajectories to reduce the vibration of rolling stock and improve ride quality during trains passing over a track. The development of a simulator that can confirm the error of the actual tamping work is important for reducing human error in the linearization of the track misalignment. In this study, to improve the reality and training effect of conventional 2D simulator, 3D simulator modeling was implemented for tamping work of special railway vehicles in virtual space. The problem of buffering during high screen quality of tamping work was solved using the Unwrap UVW mapping technique of a low polygon extracted from high quality polygon modeling. The human error in the training of the tamping work was detected by the principle of circle and square collision when the tamping tyne and the sleeper collided. In addition, vibration of the driving chair was generated at the same time as the collision, and the number of the sleeper strikes is displayed on the simulator exercise screen. Owing to the scattering of railway ballast protruding from the sleepers, which had a serious effect on the safety of the vehicle, the gravel bouncing effect of the tamping unit was applied.

• 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.

• Journal of the Korean Society for Railway
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• v.3 no.3
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• pp.147-153
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• 2000

The train control and monitoring system (TCMS) is an on board computer system in railway vehicles performing the control, supervisory and diagnostic functions of the complete train system. This system replaces a lot of hard-wired relays and minimizes the necessary vehicle wiring thus increasing the reliability of the train. It is also one of more important equipment on vehicle to implement much higher safety and reliability train system. We studied a software design technique of TCMS using a CASE tool that is a kind of safety critical software engineering tool (SCADE). This tool has mainly four functions such as the graphical editor, the document maker, tile automatically code generator, and the test simulator. The several functions of TCMS are implemented in this software easily programmed using a functional block diagram and a graphic programming language. We applied to automatically generated TCMS modules on the SCADE each functional block for the Standard type EMU in Korea. We performed the combination test using TCMS simulator and the running test in Seoul subway 7 Line. We proved that this technique is more useful for the software design of TCMS in urban transit

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.590-595
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• 2008

A large-scale fire test was done for interior materials from a vehicle installed within a fire test room. The interior materials are the old style before interior replacement by the Korean guideline for the safety of rail vehicle. Ignition source (gas burner) was increased in several controlled steps. The objectives of this test are to assess the fire performance in terms of ignition and flame spread on interior lining materials and to provide data on an enclosure fires involving train interior materials that grow to flashover. This data will be used to develop and calibrate an Fire Dynamics Simulator (FDS) model for fire growth on the interior vehicle.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1061-1067
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• 2010

In this paper, we propose a simulator for testing of the Navigation Control System(NCS) in Bimodal-tram. NCS uses values of all sorts of sensors installed in vehicle to decide current position, and to control speed and steering of vehicle to go to a next position. Major functions of simulator are input processing of the driver and generation of virtual sensor data and driving profile(navigation path, magnetic information), and the NCS function. Virtual sensor data is generated according to output data from the NCS, driving profile and input processing of the driver, and monitoring systems is operated separatedly to confirm of NCS operation. This paper discusses about the implementation of the simulator, and analyzes and evaluates the simulation results.