• Proceedings of the KWS Conference
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• 1993.05a
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• pp.38-40
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• 1993

• International Journal of Korean Welding Society
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• v.4 no.1
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• pp.1-9
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• 2004

Continuously welded tracks, first introduced on train lines, are being used increasingly in Europe. And the different arc welding methods are only used on minor lines, private tracks and in the manufacturing of switches and crossings. Mobile flash butt welding belongs the future in rail welding on side if new tracks have to be erected. The following contribution reviews the processes available, usual test methods for welded rail joints and various applications.

• Korean Journal of Remote Sensing
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• v.25 no.2
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• pp.107-112
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• 2009

A technique for the simulation of various kinds of ground based SAR system was developed. This is an ancillary research for the development of an ArcSAR system which uses an arc-rail as a platform for the antenna movement instead of linear rail. The results of applying conventional Deramp FFT based SAR focusing algorithm to the simulated raw signal of linear rail type ground based SAR for the point targets showed that the developed simulation technique generated accurate GB-SAR raw signal. The developed technique is now being used for the development and verification of SAR focusing algorithm for the arc-rail type ground based SAR. The simulation technique is also expected to be very useful for the purpose oriented system design and operation planning of ground based SAR technique.

• Journal of Welding and Joining
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• v.8 no.1
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• pp.54-61
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• 1990

A pilot production is made to the high carbon Cr-Ti alloy rail steels with slight quantity of Cr & Ti added to the eutectoid carbon steel. As a part of weldability of these alloy steels, SH-CCT diagram for welding is first applied to the high carbon Cr-ti alloy rail steel with 0.1wt% Ti. The microstructure, which will be appeared at the HAZ of Enclosed-arc welding of this alloy rail seel, is a single phase of pearlite. As a result of this, it shows that the welding condition of Enclosed-arc welding applied to this alloy rail steel is a good condition.

• Korean Journal of Remote Sensing
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• v.27 no.1
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• pp.25-31
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• 2011

Precise control of antenna position is very critical in ArcSAR system which uses an arc-rail as a platform for the antenna movement instead of linear rail. In order to minimize the antenna positional error, we improved the motion driving system and applied a newly developed motion control S/W which utilizes the real time antenna position information from magnetic linear scale and encoder. The experimental results showed that the rotational RMS error was reduced to $0.0062^{\circ}$ from $0.0432^{\circ}$. In terms of antenna positional RMS error for the arm length of 3m, it was reduced to 0.324mm from 2.262mm. It is expected that the ArcSAR system can be used to monitor the sub-millimetric displacement of terrain and structural targets.

• Journal of Power System Engineering
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• v.8 no.4
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• pp.17-23
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• 2004

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support and two screw jacks. And the control algorithm demands two controllers. One controller is designed such that the screw jack 1 and 2 follow the position reference signal generated by a tilt sensor. The other controller of two degree of freedom is designed to remove the synchronous error occurred between jack 1 and jack 2. The simulation results show that the desirable control performance is achieved.

• Computational Structural Engineering
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• v.9 no.2
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• pp.143-151
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• 1996

The optimal design for Electro-magnetic Launcher (EML : Rail Gun) considering structural and electrical constraints are presented. For the structure of EML under high pulsed currency, the cross section is minimized subject to maximum stress of each element(rail, side wall, ceramic, and steel) within allowable stress and preload limits. The electrical constraint is the effective ceramic thickness which prevents the eddy current effect reducing the performance of EML. The stress analysis and optimization procedure of 90mm EML is conducted with ANSYS Code. The optimal design under preload is reduced to 53% of area compared with optimal design without preload. In case of rail with arc angle .theta.=45.deg., the performance of EML is the best among the other rail arc angles. The optimal design for rail with arc angle .theta.=45.deg., results in the reduction of 9% of area and 10.4% of deformation compared with Fahrenthold's design. The optimal preload 59.8MPa is much lower than Fahrenthold's design(186MPa). The results show that the optimal design of EML meets the design requirements.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1661-1666
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• 2009

This paper is analyzed the effect on characteristics of thrust force of linear induction motor(LIM) by arc type tester. Many kinds of tester have a rotational shape because of a finite length of railroad. Whereas effects by using rotational type tester are generally unknown. For reason of that, this paper is analyzed the effect on characteristics by rotational type tester using 2D finite element method(FEM), and then is compared a thrust force between linear type tester and rotational type tester. Analysis model is decided by numerical modeling for fitting the LIM for propulsion system of light rail, and it is changed to proper arc model. And then we analyzed the arc and the linear model. Consequently, arc type tester is not only useful experiment but also efficient simulation method, and small error is occurred between linear and arc model.

• Korean Journal of Remote Sensing
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• v.28 no.2
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• pp.237-243
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• 2012

In this paper, an atmospheric effect of repetitive measurements of X-band (9.65 GHz) arc-rail type GB-SAR (ArcSAR) system was quantitatively analyzed. Four artificial triangular trihedral corner reflectors as stationary targets for getting stable back scattered signal during 43 hours continually. The results of the analysis showed that the phase of those stationary targets had changed maximum of 5 radian (12.4 mm) and total RMS error had was 1.62 radian (4 mm) during 65 repeated measuring time. The refractive index of air which was calculated using the temperature;humidity and pressure of atmosphere showed very close relationship with the phase difference. We could check the atmospheric correction was fulfilled by the correction of an atmospheric effect using refractive index during the selected 16 hours period showed that RMS error was dropped from 1.74 radian (4.3 mm) to 0.10 radian (0.24 mm).

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.663-667
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• 2003

Mechanical force acted on the rail wheel causes excessive wear and increases the maintenance cost. The present paper proposes newly designed wheel profiles in order to reduce the contact stress. Numerical analysis on the stress distribution of wheel-rail contact stress is carried out using ABAQUS, a commercial finite element code. The result of KNR1/40 conical wheel is compared to those of the proposed wheels, all of which are arc wheel profile type.