• 한국자동차공학회논문집
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• 제6권4호
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• pp.24-31
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• 1998

In this study, a procedure is presented for the dynamic analysis of a multibody tracked vehicle system. The planar vehicle model used in this investigation is assumed to consist of two kinematically decoupled subsystems. i.e., the chassis subsystem and track subsystem. The chassis subsystem includes the chassis frame, sprocket, idler and rollers, while the track subsystem is represented as a closed kinematic chain consisting of rigid links interconnected by revolute joints. The nonlinear contact force modules describing the interaction between track links, and sprocket, idler, rollers and ground will be developed.

• Geomechanics and Engineering
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• 제13권1호
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• pp.161-171
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• 2017

The underlying ground state of a railway plays a significant role in maintaining the integrity of the overlying concrete slab and ultimately supporting the train load. While effective nondestructive tests have been used to evaluate the rail track system, they can only be performed during non-operating time due to the stress wave generated by active sources. In this study, finite element numerical simulations are conducted to investigate the feasibility of detecting unfavorable substructure conditions by using a moving train load. First, a train load module is developed by converting the train load into time-variant equivalent forces. The moving forces based on the shape functions are applied at the nodes. A parametric study that takes into account the bonding state and the train class is then performed. All the synthetic signals obtained from numerical simulations are analyzed at the frequency domain using a Fast Fourier transform (FFT) and at the time-frequency domain using a Short-Time Fourier transform (STFT). The presence of a void condition amplifies the acceleration amplitude and the vibration response. This study confirms the feasibility of using a moving train load to systematically evaluate a rail track system.

• 한국정밀공학회지
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• 제20권6호
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• pp.178-188
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• 2003

A study on the dynamic analysis of a tracked vehicle for mining on deep-sea bed with very soft soil is presented. An equation for the interaction between track and soft soil is employed to develop a track/soil interaction module called TVAS. The vehicle is modeled as a multi-body dynamic system using a multi-body dynamic analysis program. The developed module is incorporated into the multi-body dynamic analysis program with a user subroutine. The dynamic behavior and design of the mining vehicle on deep-sea bed is investigated.

• 한국자동차공학회논문집
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• 제9권1호
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• pp.205-215
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• 2001

In this study, modeling and analysis procedure for the dynamic analysis of a high mobility tracked vehicle system were studied. The vehicle model used in this investigation is assumed to be consist of two kinematically decoupled subsystems. The chassis subsystem consists of chassis frame, sprocket, support rollers, road wheels, idler wheel, road wheel arms and idle wheel arm, while the track subsystem is represented as a closed kinematic chain consisting of track links and end connectors interconnected by revolute joints with bushing. Nonlinear contact force module describing the interaction between track link, and sprocket, idler wheel, road wheel, support roller, ground was used. The effects of road wheel arms and idler wheel arm due to tension adjuster are also considered.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.928-934
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• 1998

This paper describes a fully digitalized driver for BLDC motors which is realized by a single chip microprocessor. The speed change can be done by using the signal obtained from the position detecting sensor and adjusting the pulse width at the input channel of power module. In order to establish a speed control system a repetitive control method is adopted to track a periodic refer-ence change in the BLDC motor system. The experimental results show accurate reference track-ing performance under the given periodic reference in the repetitive controller design.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.143-148
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• 2011

This paper is about the study on MPPT algorithm of PV module where mismatched solar cells exist. PSIM simulation tool was used to verify new MPPT algorithm and PV module modeling was made. It was verified for the proposed algorithm to track the right MPP of PV boost converter under mismatched condition, which shows a shading effect in PV module. An experiment will be done soon using PV simulator for verification of the proposed algorithm.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.269-275
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• 2000

The railway signaling system consists of microcomputerized vital devices on board and ground, which are connected to one another by track circuits, and interlocking equipment for route control. Therefore it is important to validate the required functions of developed system and interface between developed signaling systems. To verify the conditions and functions of signaling logic, the laboratory prototype test bench, which consists of personal computers with software module and Ethernet LAN, will be developed. In this paper general design of signaling system test bench for high-speed rail is described and developed software module is presented.

• 대한토목학회논문집
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• 제42권6호
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• pp.837-842
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• 2022

2013년에 개발된 지능형 철도선형계획 프로그램(ei-Rail)은 주로 해외의 신규 철도건설사업 사전 기획 분석 및 설계 결과 검증 등에 활용되어왔다. 그러나 한국 철도산업의 해외 진출 대상국인 개발도상국에서는 대규모 비용이 소요되는 신규 철도건설사업 보다는 기존 철도의 선형개량을 통한 증속, 또는 단선철도의 복선화 등의 사업이 보다 필요하고 실행가능성이 높은 것으로 판단되며, 이런 유형의 사업수요가 지속적으로 발생하고 있다. 이에 본 연구에서는 기존의 신규 철도건설 사업 분석기능 중심의 ei-Rail 프로그램에 철도복선화 사업 분석기능을 추가하고자, 철도 복선화사업 모듈을 개발하였다. 기존에 운행 중인 철도 선형자료를 기반으로 복선화 사업의 종류와 규모를 반영하고 대상 지역별 공종 단가를 적용하여 공사비를 산출하고 설계도면 제작을 자동화할 수 있도록 하였다. 그리고 해외의 사례 적용을 통하여 ei-Rail의 복선화 사업 분석기능을 검증하였다. 향후 해외를 대상으로 하는 철도 복선화 사업의 기획 및 분석결과 검증을 보다 효율적으로 수행할 수 있을 것으로 기대한다.

• 전자공학회논문지A
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• 제33A권4호
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• pp.142-151
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• 1996

This paper presents a new symmetrical routing architecture for FPGA and an efficient routing algorithm for the architecture. The routing architecture adopts the segmented wires and the improved switch modules. Segmetned wires construct routing channels which pass through the chip in vertical and horizontal directions. To maximize the utility of a track, a track in each switch module can be separated in two part using a programmable switch to route two different net. The proposed routing algorithm finds all assignable tracks for a given net and selects the best track from assignable tracks to minimize the number of programmable switches and the unused portion of the wire segments. In order to stabilize the perfomrance of the algorithm, the routing order is defined by weighted sum of the number of wire segment, the length of wire segmetn, and the number of pin. Experimental results show that routability is improved dramatically and the number of crossing switches are reduced about 40% compared with the previous works.

• 한국지능시스템학회논문지
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• 제22권6호
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• pp.741-747
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• 2012

본 논문에서는 감시 시스템에서 다중 물체를 감지하고 추적하기 위한 빠르고 강인한 알고리즘을 제안한다. 제안된 시스템은 감지 모듈과 추적 모듈, 2개의 모듈로 구성된다. 이동 물체의 감지 모듈에서는 우리는 영상 이진화 기법과 프레임별 영상을 이용하여 움직이는 물체를 추출하고, 모폴로지 기법을 이용하여 각종 노이즈를 제거한다. 또한, 블록 기반 히스토그램기법을 사용하여 인간과 다른 물체를 구분하는 방법을 제안한다. 이동 물체의 추적 모듈에서는 색상 기반 추적 알고리즘과 칼만 필터가 이용된다. 먼저 RGB 영상을 HSV 영상으로 변환한 후, 다중 물체를 추적하기위해 색상 기반 추적 알고리즘을 사용한다. 이때 다른 물체와의 충돌시 물체를 추적하기 위해 칼만 필터를 사용한다. 마지막으로, 제안된 방법을 몇 가지 실험을 통해 그 효용성 및 응용 가능성을 보인다.