• Journal of the KSME
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• v.53 no.2
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• pp.49-53
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• 2013

철도차량은 중요한 친환경 대중교통 수단으로서 운행 구간이 확장되고 있다. 그러나 철도선로가 거주지역을 통과하여 설치되면서 환경 소음 문제가 야기되고 있으며 이의 저감이 중요한 이슈 중 하나이다. 철도차량 및 궤도에서 발생하는 전동음은 저감해야 할 주요 소음원 중 하나이다. 따라서 철도의 진동 및 소음 관련된 연구현황들에 대해 알아보고 궤도 지지단을 고려한 레일의 진동과 방사 소음 특성을 예측하고 궤도 모니터링 시스템 개발에까지 적용이 가능한 방법들에 대한 연구가 필요하다.

• Journal of Intelligence and Information Systems
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• v.13 no.3
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• pp.101-117
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• 2007

In this paper, we propose a customized genetic algorithm (GA) to find the minimum-cost guideway network (GN) of personal rapid transit (PRT) subject to connectivity, reliability, and traffic capacity constraints. PRT is a novel transportation concept, where a number of automated taxi-sized vehicles run on an elevated GN. One of the most important problems regarding PRT is how to design its GN topology for given station locations and the associated inter-station traffic demands. We model the GN as a directed graph, where its cost, connectivity, reliability, and node traffics are formulated. Based on this formulation, we develop the GA with special genetic operators well suited for the GN design problem. Such operators include steady state selection, repair algorithm, and directed mutation. We perform numerical experiments to determine the adequate GA parameters and compare its performance to other optimization algorithms previously reported. The experimental results verify the effectiveness and efficiency of the proposed approach for the GN design problem having up to 210 links.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.1
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• pp.28-42
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• 2013

Personal Rapid Transit(PRT) is a new unmanned transportation system using electricity. The purpose of the PRT is relieving the congestion of city traffic and connecting between inner city and airport, high-speed railroad. PRT requires to develop devices for the guarantee of safety and reliability. PRT as the mean of rail transportation must be equipped with control system for front rail sensing. Ultra Wide Band(UWB) radar system is suitable for PRT's detection because it has the advantage of low power consumption, low interference and high resolution. In this paper, an improved adaptive Constant False Alarm Rate(CFAR) algorithm is proposed and studied in various noise environments. The proposed algorithm improves performance in various noise environments compared to the Mean Level CFAR algorithms and other adaptive CFAR algorithms.

• Journal of Korean Society of Transportation
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• v.31 no.6
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• pp.12-21
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• 2013

Fare is critical variable when deciding project feasibility for a monorail system in tour regions. This study aims to estimate optimal fare balancing operators and users. An object of this study is Wolmi-eunha circulation monorail at Jung-Gu, Wolmido in Incheon metropolitan city. This study introduces a stepwise optimization technique to decide relevant fare ranges between operator's cost and user's cost. We found that the optimized station interval is 0.532km, the optimized headway is 0.206hour, optimal number of stations is 12, optimal number of vehicles is 3. Using these optimized variables, minimum user cost and minimum operator cost can be calculated. Optimal fare range is calculated from 1,261 Won to 5,063 Won. It is also found that sightseeing transport system has less sensitivity on access cost because distance differences among sightseeing transport stations located in the tour regions are negligible.

• Information and Communications Magazine
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• v.18 no.10
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• pp.33-43
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• 2001

LEO 통신위성 Constellation을 이용한 Packet-Level Broadcast Message 상용 서비스를 구현할 수 있는 육상, 해상 및 공중 이동체 탑재 수신 전용 단말기로 Application DTE를 직결, 차량항법 및 교통 정보 등 관련 서비스 IT화에 공헌하는 저 궤도 위성 방송망 구성 및 관련 기술을 현 운용 중인 Little LEO 개별 통신 개념으로부터 방송 형식으로 개정 연구 개발한 사항으로 소개한 것이다.

• Journal of the Korean Society for Railway
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• v.3 no.2
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• pp.28-36
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• 2000

도시철도라 함은 도시교통의 원활한 소통을 위하여 도시교통권역에서 건설·운영하는 철도ㆍ모노레일 등 궤도에 의한 교통시설 및 교통수단을 말한다. 지금까지 차량성능시험은 제작사와 운영체가 자체적으로 시행해 왔으나 신조 제작차량의 잦은 고장과 사고발생으로 인하여 교통불편을 초래하고 있어, 국가에서는 국민의 생명보호와 안전사고예방을 위하여 제도적으로 차량이 영업운행 전에 성능시험을 거치도록 한 것이다. 이에 도시철도차량성능시험에 대해서 간략히 설명하며, 관련 규정을 소개한다.(중략)

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.413-418
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• 2018

The purpose of this study is to investigate the cause of rail corrugation and the track force for concrete track (STEDEF) in the urban transit. From the field measurements, the dynamic wheel load, vertical displacement of sleeper and rail bending stress were measured and it was evaluated by regarding to the rail corrugation. As a result of the study, the causes of rail corrugation was experimentally proved by frequency analysis using measured dynamic wheel load data. The influence of corrugation on dynamic wheel load, rail bending stress and sleeper displacement was evaluated that the periodic irregularities of rail corrugation on the rail surface amplified the dynamic track force such as the dynamic wheel load, and thus the rail bending stress and the vertical displacement of sleeper could be increased by a maximum of 1.7 times.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.547-552
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• 2022

In this study, shape-based track management by analyzing track irregularity was studied in terms of force-based track irregularity analysis by numerical analysis of wheel-rail interaction force using by the measured vertical irregularity. The effect of the vertical irregularity of the track due to the difference in track types on the wheel-rail interaction force and the track acceleration in the connecting section of the sleeper floating track and the direct fixation track on concrete bed were analyzed. As the results of this study, the measured vertical irregularity was directly affect the vertical wheel load (the wheel-rail interaction force) and the rail acceleration, and it has been demonstrated to change consistently. In this study, the adequacy and necessity of the force-based track irregularity analysis method was verified based on the wheel-rail interaction analysis using the the measured vertical irregularity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4A
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• pp.719-726
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• 2006

The use of CWR track not only reduces the track maintenance cost, but increase the life cycle of track components. Therefore, the use of the CWR track has increased consistently in the worldwide. As the use of CWR increases in track structures, derailing disasters associating with track buckling also increase in great numbers due to high compressive thermal stress in the summer. Among many CWR parameters, the influence of the sectional properties of the rail was investigated on the stability of CWR track in this study. Also, the sensitivity of the broken fastener and the stiffness of the fastener system such as the translational and rotational stiffness was investigated.

• Journal of Korean Society of Transportation
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• v.9 no.2
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• pp.75-86
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• 1991

A conventional track structure system of rails ties ballast subballast and subgrade. An adequate engineering analysis require consideration of all major components of track system. This paper briefly reviews existing methods of track analysis and presents a new model based of the examination of the Tallbot Model. The new model has been validated by comparision with settlements from other model.