• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.373-379
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• 2001

When a train runs into a tunnel at high-speed, aerodynamic drag suddenly increases and the booming noise is generated at the exit of tunnel. The noise shape is very important to reduce the aerodynamic drag in tunnel as well as on open ground, and the micro-pressure wave that is a source of booming noise is dependent on nose shape, especially on area distribution. In this study, the nose shape has been optimized employing the response surface methodology and the axi-symmetric compressible Navier-Stokes equations. The optimal designs have been executed imposing various conditions of the aerodynamic drag and the micro-pressure wave on object functions. The results show that the multi-objective design was successful to decrease micro-pressure wave and aerodynamic drag of trains.

• 조명전기설비학회논문지
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• 제18권4호
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• pp.138-143
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• 2004

본 논문은 고속전철 차량에서부터 변전소까지의 고조파에 대해서 분석하였으며, 수동필터를 이용한 고조파 저감 방법을 제시한다. 고속전철 변전소가 공급하는 열차구간에 있어서 운행 열차의 수에 따라 고조파의 파급 특성을 살펴보았다. 고조파는 변압기 과열과 통신유도장해 등 문제를 일으킬 수 있다. 이러한 고조파에 의한 손상을 줄이기 위하여 본 논문은 고조파 저감방법을 제시하였다. 제안된 방법은 PSCAD/EMTDC 시뮬레이션에 의해 증명되었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.469-472
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• 2007

Aeroacoustic sound induced from inter-couch spacing is an important contributor to interior noise generation for high speed trains. Especially the open space between mud-flap has significant impact from flow-structure interactions. To understand noise generation mechanism, experiments were performed using the wind tunnel. To find mud-flap parameters for minimal noise generations the various shape of the mud-flap was installed and its effects on the wall-pressure generation were investigated.

• 한국강구조학회 논문집
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• 제8권3호통권28호
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• pp.47-54
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• 1996

Recently Sucessive progress in train technic has enabled us to constructed high-speed railways for ourselves. This caused more rapid train more pressure on a track and speedier track break-down. Especially in the construction of high-speed rails for high-speed traveling and safety accurate breaking distance is essential and not only computation of rolling resistance in theory but also verification through real measurement are important in basic material for breaking and starting load caused during the train running. In this study, we measured traveling resistance and calculated traveling resistance formula in the case of the SAEMA-EUL which consists of main part of current passenger trains and frights in this country.

• 전기학회논문지
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• 제64권5호
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• pp.812-816
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• 2015

Recently, various monitoring systems have been proposed to detect interaction performance between trains and infrastructure, as well as, various techniques to improve the accuracy and performance of such inspection equipment in high speeds. Especially, it is important to predict electric noise of high speed trains due to its effect on detection system accuracy. In this paper, we analyze various types of electrical noise in electric vehicles to improve the accuracy of the detection module of the inspection car. In detail, analysis of electric noise of high speed railway is performed as a function of speed based on field tests that were carried out by HEMU-430X (Highspeed Eletric Multiple Unit - 430 km/h eXperiment).

• 한국철도학회논문집
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• 제18권4호
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• pp.374-390
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• 2015

본 연구는 대표적 선로용량 부족구간인 경부선 서울~금천구청 구간을 분석대상으로 열차운행횟수에 따른 열차 지연도착 발생확률을 추정하고, 이를 통해 정시성 개선 편익을 반영할 수 있는 방안을 마련하였다. 코레일의 열차운행자료를 기초로 연도별/월별/시간대별 지체발생수준을 분석하였고, 고속 및 일반열차의 열차운행횟수에 따른 지연발생확률을 선형회귀분석으로 모형화하였다. 분석결과, 해당구간 지연발생확률에 일반열차 운행횟수가 고속열차 운행횟수 보다 1.4~2.8배 더 큰 영향을 미치는 것으로 나타났다. 이를 기초로 정시성 개선 편익의 산정방법론을 제시하였고, 실제 서울~금천구청간 선로용량 확충사업에 대하여 사례분석을 수행한 결과, 연간 42~45억원 규모의 편익이 발생하는 것으로 분석되었다. 본 연구를 통해 선로용량 부족구간에 대한 용량확충사업의 편익과 경제적 타당성을 제고시킬 수 있을 것으로 기대된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.989-995
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• 2010

This paper is focused on a simplified measurement of rail irregularity by some axle-box accelerometers for high-speed rail condition monitoring with in-service high-speed trains. Generally, the rail condition monitoring has been done by a special railway inspection vehicle with a 10m versine method. But, the monitoring method needs some expensive measurement system, and have been performed only at night due to its speed limit. In this research, a simplified measurement of rail irregularity using axle-box accelerometers is proposed to monitor the rail condition with in-service high-speed trains. The acceleration is measured by using two accelerometers on a axle-box, and stored in an on-board data acquisition system. The displacement is estimated from the acceleration data by a combination of Kalman filter and the frequency selective filter. The estimated results are compared with the measurement from a laser rail inspection system which is near the axle-box. From the comparison, the proposed method shows promise as a tool for the simplified measurement of rail irregularity at high-speed.

• 대한토목학회논문집
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• 제37권2호
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• pp.379-387
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• 2017

최근 고속철도 평균 좌석이용률이 98% 수준에 이르면서 고속철도 차량 내 혼잡이 발생하는 문제가 나타났고, 이러한 배경에서 본 연구는 고속철도 차량 내 혼잡도 완화에 따른 고속철도 이용자들의 편익을 추정하기 위하여 이용자들의 지불 용의액을 산정하였다. 진술선호자료에 근간한 조건부 가치측정법과 토빗(Tobit) 모형을 통해 지불 용의액을 추정한 결과, 지불 용의액은 소득 수준 및 혼잡도 수준과 비례하는 것으로 나타났으며, 남성, 특실이용자, 자유석 및 정기권 이용자의 지불 용의액이 높고, 주말 이용자, 주부, 통근목적이나 여가목적 이용자들은 지불 용의액이 낮은 것으로 나타났다. 본 연구에서 산정된 지불 용의액은 철도운영자들의 좌석공급 확대를 위한 노력에 대하여 정부의 지원근거나 사회적 편익을 계량화할 수 있는 근거를 제공하였다는 점에서 의의가 있다고 하겠다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.229-234
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• 2004

When trains run over a snow-covered track at high speed, the snow accereted under car bodies may drop during train running. The dropped snow lumps scatter the ballast on the track damaging the car body and the environment along the track in snowy regions. In this study, various countermeasures to prevent the ballast from scattering has been investigated and compared. Furthermore, the implementation of the ballast-flying prevention methods to passing-by station has been examined through which the KTX train passes about 300km/h speed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.303-311
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• 2002

A first evaluation of the possibilities of high speed trains in conventional railway in Korea have been investigated. The radius of curvature was considered the major problem with high-speed trains in Korea. If KNR(Korea National railway) likes to increase the speed, is then whether KNR shall construct straigthen the track or develop a train that can reduce travel time in curves The research concerns structural design of train car-body is to reduce heavy stress concentration. Using 3D solid modeling, Finite Element analysis and shape optimization combined with powerful postprocessing, graphical display and animation to achieve complete and accurate design and performance will be carried out further project Main purpose of this project is to provide korean tilting train car body's conceptional design. Based on first year research results, the design of car-body will be performed by train manufacture.