• Proceedings of the KSR Conference
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• 1999.11a
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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.

• Proceedings of the KSR Conference
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• 2011.10a
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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.

• Journal of the Korean Society for Railway
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• v.3 no.1
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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$\^{C}$.

• Proceedings of the KSR Conference
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• 2001.10a
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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.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.1
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• pp.16-26
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• 2002

A web based mail system consists of servers and clients. A server side takes charge of making rail accounts and service, a client side does interfacing with users. In this paper, we designed the mail system with multi-domain facility. Also we implemented both a ussr environment based on the internet explorer and management environment based on the windows server 2000. Using the service engine of rail system, we could provide the user efficiency through responding user absence, automatic mail sorting, verifying receipt and refusing messages, and implemented the rail system which provides the reliable system.

• Journal of Mechanical Science and Technology
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• v.18 no.9
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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.

• Proceedings of the KSR Conference
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• 2004.10a
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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.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.600-606
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• 2007

3D finite element analyses of a corrugated steel web girder and a steel truss web girder are conducted to investigate the static and dynamic behaviour of the hybrid girders. And the analyses results are compared with those by the equivalent beam theory. The equivalent theory is a theory that all section properties of a truss structure are replaced by section properties of a beam including a shear coefficient. When applying the equivalent beam theory, the shear coefficient of the corrugated steel web girder is estimated as the area ratio of flange section to web section and that of the steel truss web girder is calculated by the equation proposed by Abdel. Static deflections and natural frequencies by 3D finite element analyses and those by the equivalent beam theory are in good agreement.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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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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• v.18 no.5
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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.