• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.12
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• pp.2121-2133
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• 1997

A finite element code is developed for 3-D self-contact problems, using continuum elements with a SRI(Selective Reduced Integration) scheme to prevent locking phenomenon by the incompressibility of rubber. Contact treatment is carried out in two ways : using the displacement constraints in case of rigid contact ; and imposing the same contact forces on two contact boundaries in case of self-contact. The finite element code developed is applied to the deformation analysis of C.V.joint boots which maintain lubrication conditions and protect the C.V.joint assembly from impact and dust. The boot accompanies large rotation depending on the rotation of the wheel axis and leading to the self-contact phenomena of the boot bellows. Since this contact phenomenon causes wear of the product and has great influence on the endurance life of the product, it is indispensable to carry out stress analysis of the rubber boots. In case of self-contact, various methods for determining contact forces have been suggested with an appropriate contact formulation. Especially, the types of penetration in self-contact are modularized to accelerate conputation with a contact algorithm.

• Journal of the Korean Society for Railway
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• v.17 no.2
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• pp.133-139
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• 2014

Due to the absence of design guidelines for elevated light-rail structures in Korea, most elevated light-rail structures have been designed and constructed based on the design codes of conventional railway bridges and on the codes recommended by foreign vehicle manufacturers. This is the main reason why most elevated light-rail structures are massive or over-designed or poorly constructed economically. In this paper, the authors carried out field tests to analyze the braking forces caused by braking a train running at speeds of 50km/h, 60km/h, and 70km/h, acting on the elevated structures of rubber-wheeled Light Rail Transit (LRT) trains. The authors also briefly describe the analyzed results of the braking force acting on the substructures of elevated light-rail structures. The test-results presented here in this paper can be referenced when establishing design guidelines or standards for elevated structures of LRT systems.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1191-1198
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• 2011

The railway business was began at England in 1767. Since then, it has been changed for configuration of rail over the years and made in the form of I. The train propulsion has been developed in a engine of steam, diesel, motor, electromagnetic force and a pneumatic engine, continuously. also, the friction has been improved in a steel-wheel, rubber tire, frictionless maglev system and railless system. In consequence, the efficiency and improvement speed for train have been accomplished. In this paper, it is investigated for the structure with lightweight using the change for supporting the form of lateral pressure by centrifugal force in the substructure supporting load for railway vehicles.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2830-2837
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• 2011

In this paper, a flexible track modeling of turnout was developed and dynamic characteristics of turnout rails were analyzed when a vehicle passed through the turnout. The flexible track modeling is effective to the stiffness and durability design of turnout, because it can capture the deformation and dynamic stress due to the collision of between wheels and rails when the vehicle move to the tongue rail. Also, a more accurate running safety can be obtained by considering the interaction between wheel and rail deformation. Solid finite elements were used for variable cross-sections of rails and the variation of rubber stiffness was modeled. The proposed flexible track modeling in this paper was verified to be valid by comparison with the experiment of the turnout system.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.47-50
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• 2011

Test Results of noise, ride comfort and vibration tests are investigated for three kinds of light rail transit vehicles which have passed the performance test and the test criteria has been satisfied. Noise level of light rail transit vehicles was 64~69dB(A) at stop and 74~75dB(A) when operated at full speed. The ride comfort index according to UIC 513R was 2.02 to 2.45. Vibration level of rubber tired light rail transit vehicle was from 'normal' to 'good' and that of iron wheel light rail transit vehicle was 'good' to 'excellent'. These data are the results for three kinds of light rail transit vehicles and more data can be accumulated after further performance test. These data can be used for a reference for the design of light rail transit vehicles.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2718-2725
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• 2011

The VAL 208 in Uijeongbu Light Rail system is a light railway vehicle which could be operated in driverless supported by Siemens. It is a Rubber Wheel Type AGT (Automatic Guideway Transit). It will be operated in two car train about 11km of Uijeongbu line. In this paper, the technical overview of the ATC system and the interface between the system and the way side control equipments are presented. It includes the main functions of OBCU(On Board control Unit) and its information sharing method with WCU(Way side control Unit). The testing procedure of OBCU is also discussed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.260-263
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• 2001

Mechanical properties have been accepted to be major factor to improve wear resistance. The effect of mechanical properties on wear resistance of 0.27C-0.70Ni-1.42Cr-0.20Mo steel was studied under various test conditions. It is clear that yield strength, tensile strength, impact value, and hardness are strongly related each other. Wear resistance tests as pin on plate type and dry sand / rubber wheel type proved to be that wear depends on mechanical properties. Microstructures were also observed to make clear the wear properties. At quenching and low temperature tempering, the specimen has a good wear resistance.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.450-451
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• 2008

The Bimodal tram is developed in KRRI (Korea Railroad Research Institute). This vehicle will be used in the public transportation system. The Bimodal tram has the advantages of both bus and train. Bus system has the advantages of flexibility of the routes delivering passengers to the destination and easy accessibility. Train is to meet the scheduled arrival and massive public transportations. The vehicle is the rubber tired tram and is all wheel steered single articulation. The vehicle can be automatically operated by navigation control system (NCS). For the automatic driving, the vehicle lanes will be marked with permanent magnets that are buried in the road. The control algorithm developed for navigation control has to be verified before being applied in the vehicle. In this purpose, we design the simulator for controller test of the bimodal tram.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1195_1196
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• 2009

Light rail transit is classified to rubber-tired LRT, lear induction motor LRT, steel wheel LRT, monorail and tramway. LRT except for tramway are usually operated without driver and tramway are driven depending on driver's sight like usual car. LRT, which is one type of urban guided transit, shall be operated according to domestic "Operational Regulation for Urban Guided Transit" but existing regulation does not contain the safety related codes for driverless operation. In this paper, we investigate "IEC 62267 : Railway Application-Safety Requirements for Automated Urban Guided Transit" and compensate for existing operational regulation by referring to international standard and operational rule of commercial line.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.148-153
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• 2007

The effect of silicon carbide (SiC) and graphite fillers incorporation on the abrasive wear behaviour of glass-vinyl ester (G-V) composites have been investigated. The three-body abrasive wear behaviour was assessed by rubber wheel abrasion tests (RWAT). The worn surfaces were examined using scanning electron microscopy (SEM). The addition of SiC and graphite fillers in G-V composite improves the abrasion resistance under different loads/abrading distances. The SEM studies indicate the reasons for failure of composites and influencing parameters.