• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.747-750
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• 1995

As railway trains run faster high performance braking system are necessary because more energy needs to be dissipated due to increased kinetic energy. In this work a portable computer based prediction system for emergency braking distance has been developed. The algorithm for the system is based on braking theory and empirical results of actual braking test. The computer is connected to the sensors to measure the velocity and the braking pressure in real train. It is expected that this system will be utilized to predict emergency braking distance during actual operation of the train

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.54-56
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• 1997

In this paper, The considerable matters for the calculation and determination of the rated electric power of the three phase Linear Induction Motor for the propulsion of a vehicle, is treated with inverter performance with harmonics, aerodynamic drag force, running resistance, normal force.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.375-378
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• 2007

Abrasive wear between piston ring face and cylinder liner is an extremely unpredictable and hard-to-reproduce phenomenon that significantly decreases engine performance. Wear by abrasion are forms of wear caused by contact between a particle and solid material. Abrasive wear is the loss of material by the passage of hard particles over a surface. From the pin-on-disk test, particle dent test and scuffing test, abrasive wear characteristics of diesel engine cylinder liner-piston ring have been investigated. Pin-on-disk test results indicate that abrasive wear resistance is not simply related to the hardness of materials, but is influenced also by the microstructure, temperature, lubricity and micro- fracture properties. In particle dent test, dent resistance stress decreases with increasing temperature. From the scuffing test by using pin-on-disk tester, scuffing mechanisms for the soft coating and hard coating were proposed and experimentally confirmed.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.3
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• pp.1-8
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• 1995

In the companion paper of the present paper, a coast down test method to determine the resistance forces on running vehicle based on the distance-time measurement was explained along with the suggestions to improve its accuracy and testing methodology. In the present paper some of the suggestions discussed previously are implemented and actually road tested to see the applicability of the improved method(short distance method) in the field. From the results. it is shown that the short distance method which requires only 600m long proving ground road gives at least comparable results on the accuracy compared to the original S-t method which requires 2000m. It is hoped that the present method be further refiend to give more accurate results.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1765_1766
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• 2009

In this paper, we propose the mathematical model for the vehicle system and the observer for adhesion force. To model the dynamic properties of vehicle system, we have considered two fundamental parts. The first part is the motion equations for vehicle based on Newton's second law. The second part is the torque dynamics of the traction motor. These parts are affected by outer conditions such as adhesive coefficient, running resistance and gradient resistance. The each parts are presented by the numerical formula. From two equations, we get the observer on adhesion force. Simulation results show that the proposed observer have the good performance compared with the normal observer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.292-292
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• 2010

Bimodal Tram is driven by both engine and Lithium Polymer battery pack which consists with 168 cells of LPB(80Ah, 650Vdc). LPB pack is very frequently charged and discharged in driving. Temperature inside of LPB pack makes an great effect on both charging and discharging capacity which seem to be related with LPB internal resistance. LPB internal resistance is increasing or little decreasing with the decreased temperature under 10 - $20^{\circ}C$ and the increased temperature over $30^{\circ}C$ which is similar to the temperature characteristics of single LPB cell. This paper has analyzed the driving characteristics of LPB pack for bimodal tram is running with either battery mode or hybrid mode.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.1-6
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• 2011

This paper proposes a new design method for electric scooter which can maximize the power efficiency at the given driving condition. The proposed method is designed with the electric and mechanical parameters and driving dynamics. These values are extracted from the dynamic and mathematical equations of the scooter. For validation, numerical simulation results are presented in this paper. As a result, the scooter achieved over 80% efficiency at 360 rpm at 1.42kw load. It is clear that the proposed method was verified through a 1.42kw numerical model.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.787-792
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• 2004

LRB(Lead rubber bearing) has small resistance force against slowly acting loadings such as temporal and creep loadings vice versa large resistance force against rapid loadings such as earthquake and braking loadings. By those mechanical characteristics, it has the advantage to reduce longitudinal load acting on abutments and piers, and moreover to in1prove the running stability of train by restricting the behavior of bridge under the required level. In this study, a stability evaluation method of CWR on the bridge with LRB is presented. Several parametric studies are carried to investigate how LRB contributes to the improvement of CWR stability.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.551-562
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• 2000

The study was carried out about the design of power Car for Korean High Speed Train of maximum operating speed of 350km/h. The running resistance accounts toy the greater part of overall resistance to front hue motion. So, The Power Car's shape has to be mainly determined by aerodynamic considerations. In the train configuration of the KHST, the front and rear power cars assume the role of a locomotive. They accommodate all the machinery for providing traction. The train is controlled and monitored from power cars. This report was descrived, which focuses on aerodynamics, mass balance, the car body and the layout of the equipment that is fitted into power car.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.2
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• pp.232-238
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• 2013

The vehicle system is a multi-domain system that requires many branches of science and engineering. Therefore the development of the vehicle system requires the use of design methodologies that utilize simulations, which have grown increasingly sophisticated in recent years. Our research group proposed a simulation modeling method based on the VHDL-AMS language. This paper describes how VHDL-AMS is used to model of vehicle fuel consumption simulation. The fuel consumption is shown using proposed simulation model on the Japanese 10-15 mode. We examine the influence of the vehicle system with electrical load and hill climb resistance in the vehicle running resistance.