• Multiscale and Multiphysics Mechanics
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• v.1 no.3
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• pp.261-270
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• 2016

The longitudinal velocity (forward speed) having significant importance in proper running of railway wheelset on track, depends greatly upon the adhesion ratio and creep analysis by implementation of suitable dynamic system on contamination. The wet track condition causes slip and slide of vehicle on railway tracking, whereas high speed may also increase slip and skidding to severe wear and deterioration of mechanical parts. The basic aim of this research is to design appropriate model aimed estimator that can be used to control railway vehicle forward velocity to avoid slip. For the filtration of disturbance procured during running of vehicle, the kalman filter is applied to estimate the actual signal on preferered samples of creep co-efficient for observing the applied attitude of noise. Thus error level is detected on higher and lower co-efficient of creep to analyze adhesion to avoid slip and sliding. The skidding is usually occurred due to higher forward speed owing to procured disturbance. This paper guides to minimize the noise and error based upon creep coefficient.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1-6
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• 2006

The gauge - adjustable wheelset system in the transcontinental railway represents a more effective way in comparison with other techniques for overcoming difference in track gauges. Moreover, freight trains having the gauge - adjustable wheelsets will be run various curved tracks of Eurasian railroad network such as TKT, TCR and TSR. Therefore, to assure the safety of the gauge - adjustable adjustment wheelset system, it is necessary to evaluate durability of locking parts in the system during freight trains' service in the curved track. In this study, it was performed to estimate fatigue life of locking parts under lateral wheel pressure by using durability simulator.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.5669-5675
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• 2012

To reduce the cost and the time of transport in Eurasian railroad networks such as TKR(Trans-Korea Railway), TCR(Trans-China Railway) and TSR(Trans-Siberia Railway) owing to the problem of different track gauges (narrow/standard/broad gauge), it is important to develop the gauge-adjustable wheelset(GAW) system to adapt easily to these gauges. The Korean GAW system is developing and will be adapting to the brand new freight trains' to improve the conventional overseas GAW system. In this study, structural and durability analyses are performed from the viewpoint of the safe-life design. The core parts of the system might be safe in range of $1{\times}10^7$ cycles from the result of durability analysis. Moreover, to examine the safety of the system while running on a track, rig fatigue test was performed according to UIC code. The safety of the Korean GAW system is demonstrated through testing that all safety-relevant conditions are satisfied.

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.203-210
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• 2011

This study formulates the theoretical wheel-set model to evaluate wheel-climbing derailments of rolling stock due to collision, and verifies this theory with dynamic simulations. The impact forces occurring during collision are transmitted from a car body to axles through suspensions. As a result of combinations of horizontal and vertical forces applied to axles, rolling stock may lead to derailment. The derailment type will depend on the combinations of the horizontal and vertical forces, flange angle and friction coefficient. According to collision conditions, the wheel-lift, wheel-climbing or roll-over derailments can occur between wheel and rail. In this theoretical derailment model of wheelset, the wheel-climbing derailment types are classified into Climb-over, Climb/roll-over, and pure Roll-over according to derailment mechanism between wheel and rail, and we proposed the theoretical conditions to generate each derailment mechanism. The theoretical wheel-set model was verified by dynamic simulations.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1237-1238
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1477-1478
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.1103-1104
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• 2009

• Proceedings of the KSR Conference
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• 2006.05b
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• pp.306-311
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• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.1043-1044
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• 2010

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.345-350
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• 2001

Dynamic behavior of high speed train is very important because the high speed train should be safe and satisfied with the ride comfort. An eddy current brake system is mounted on trailer bogie and wheelset. The eddy current braking force longitudinally exerts on the articulated trailer bogie and the attraction force vertically exerts on the wheelset. Because a frame of eddy current brake system is flexible, these forces generate the vertical vibration at middle point of the frame. Also, the vibration change the vertical clearance between an electromagnet and top of rail which affect the magnitude of braking and attracting forces. Therefore, the dynamic behavior of the eddy current braking system must be predicted for design the dynamic characteristic of its mounting system when normally operate on rail which have irregularity. Vampire program is used for prediction of the dynamic behavior of an eddy current braking system. Five design variables and five performance index are considered for optimization through D-optimal experimental design in this paper. Also model center is used to search the optimal point for sum of performance index with variational matric method.