• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.234-241
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• 1999

Rails have residual stresses produced during manufacturing processes. The residual stresses play all important role on brittle fracture, fatigue strength and derailment by producing cracks in the web of rail. The web saw-cut test is a technique developed to measure the bulk longitudinal residual stress level. It is a simple mettled to estimate a stress intensity factor, $_{4}$ for a web crack by using the radii of curvature of the upper and lower portions of a cut rail. But according to this method, $_{4}$ varies along the rail length because the curvatures along tile rail length vary In this paper, tile residual stress was estimated by Finite Element Method and tile web saw-cut method. In addition tile variation of the residual stress with time was investigated.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2866-2869
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• 2011

Concrete track to increase R&D compared to the existing gravel track 3dB(A) over the growing problem of noise has been raised. Accordingly, the noise reduction solutions for reducing the vibration of the rail that you want to reduce the noise of the concept is to develop the rail web-damper. For this purpose, first, that occurs while driving the train to simulate the vibration modes of rail vibration part of the main draw for this part of the effective vibration reduction to be made, a review of various shapes to try.

• 한국철도학회논문집
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• 제3권1호
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• pp.19-26
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• 2000

The rail temperature is important to preserve the joint gap for standard length of rail and to determine the installation temperature which has direct influence on the rail buckling and failure in welded part for continuous welded rail(CWR), Therefore, we have measured and investigated various characteristics of rail temperature for each kind of rail. As the results of this, the correlation between the atmosphere temperature and the rail temperature which is commonly used by Korean Railway should be reconsidered. Also, the daily highest '||'&'||' lowest rail temperature was occurred when each temperature is higher and when it's lower. For the light rail, the rail temperature by the sun-light increases quickly and decreases late. But the time where the highest temperature is attained is same. There are some differences between the shade and sunny place about 3.0∼4.0$\^{C}$. The temperature of rail web is almost close to the conversion rail temperature for rail expansion. The wind of 1 m/s has an influence on the rail temperature around 5$\^{C}$.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.29-34
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• 2001

In this paper, we'll change a data generated by the project for a database and make the better interface of all laboratory and a participating enterprise, constructing a knowledge-based management system to fit a characteristics within a country. Also, we'll manage the light-rail transit system development efficiently and systematically, constructing the web-based knowledge information system.

• 한국산업정보학회논문지
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• 제7권1호
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• pp.16-26
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• 2002

웹 기반 메일 시스템은 서버와 클라이언트로 구성되는데, 서버는 계정 발급, 서비스 등의 기능을 제공하며, 클라이언트는 사용자와의 인터페이스를 수행한다. 본 논문에서는 웹 기반의 다중 도메인 기능을 갖춘 메일 시스템을 설계하였으며, 인터넷 익스플로러(Internet Explorer) 기반의 사용자 환경과, Windows Server 2000 기반의 관리환경을 구현하였다. 메일 시스템의 서비스 엔진을 이용하여, 부재중 처리, 메일 자동 분류, 수신 확인 및 거부 등을 통한 효율적인 사용자 편리성을 제공하고, 메일의 폭주와 사용자의 급증으로 인한 시스템 저하현상을 극복하고, 시스템의 안정성을 제공하는 메일 시스템을 개발하였다.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1559-1564
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• 2004

The process design of hot forging, asymmetric to symmetric rib-web shaped steel, which is used for the turnout of express rails has been studied. Owing to the great difference in shape between the initial billet and the final forged product, it is impossible to hot forge the rail in a single stage operation. The numerical simulation for hot forging of asymmetric shape to symmetric shape was carried out by using commercial FEM code, DEFORMTM-2D. For comparison with the simulation results, a experiment of flow analysis using plasticine was also carried out. The results of the flow experiment showed good agreement with those of the simulation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1253-1258
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• 2004

A general idea of implementing and managing real-time control on the VDN for rail transit vehicles is presented. In particular, the virtual device network considered in this paper is composed of Ethernet as the data network and LonWorks network as the device (control) network. A LonWorks/IP web server was used as a gateway to realize peer to peer data communication on the virtual device networks. Experimental results are given to validate the suggested architecture.

• 한국철도학회논문집
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• 제10권5호
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• pp.600-606
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• 2007

복부 파형강판 거더와 복합 트러스 거더의 정적 및 동적거동 특성을 분석하기 위해 3차원 유한요소해석을 수행하였고, 이 결과를 등가보 이론에 의한 해석결과와 비교하였다. 등가보 이론은 트러스 구조의 모든 단면제원을 등가의 보로 치환함과 동시에 전단계수 등의 단면특성을 고려한 이론이다. 등가보 이론 적용 시 복부 파형강판 거더의 전단계수는 복부 단면적에 대한 전체 단면적의 비로 산정하였고, 복합 트러스 거더의 전단계수는 Abdel의 계산식을 사용하여 산정하였다. 정적해석 및 자유진동해석 결과 3차원 유한요소모델을 이용한 해석결과가 전단변형을 고려한 등가보 이론에 의한 해석결과와 잘 일치하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.26-29
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• 2006

A flat plate-column connection is susceptible to brittle punching shear failure, which may result in the necessity of shear reinforcement. In present study, experimental tests were performed to study the capacity of slab-column connections strengthened with lattice, stud rail, shear band and stirrup under gravity and cyclic lateral load. Among them, the capacity of the specimens with lattice are superior to the others due to the truss action of the lattice bars and dowel action of the longitudinal bars as well as the shear resistance of the web re-bar. On the other hand, the strengths of the specimens with stud rail, shear band and stirrup are lower than the estimated strength by the ACI, therefore design formulas of the ACI are needed to revise.

• Journal of Welding and Joining
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• 제18권5호
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• pp.77-83
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• 2000

This study proposes the analysis and evaluation method of time series ultrasonic signal using the attractor analysis. Features extracted from time series signal analyze quantitatively characteristics of weld defects. For this purpose, analysis objective in this study is fractal dimension and attractor quadrant feature. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange even though the types of defects are identified. These difference in characteristics of weld defects enables the evaluation of unique characteristics of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hole) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimensions. Proposed attractor analysis and DAC in this study can enhance the precision rate of ultrasonic evaluation for defect signals of rail weld zone such as side hole and crack.