• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1068-1075
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• 2009

The Soil-nailing installed to the slope or the vertical excavation surface shows reinforce effect using frictional resistance between ground and grout. This friction is showed the more the shape of grout is rough, the more efficient.. This study is about the characteristic behavior of Soil-nailing has partial extension grout made artificially control. In this study, we refer to the new boring machine that can make partially extended grout and perform 3D analysis between of the partial extended grout and the general grout of a cylinder shape using the finite element method for comparing.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.555-560
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• 2006

As it has been reported that more than 60% of transmission line faults occurs due to lightning strokes, lighting is one of concerned issues in electric power utility company. Most of transmission line is double circuit in Korea. Double circuit outages account for 33.7 percent of total lightning faults from 1996 to 2004. Even though transmission fault might be cleared shortly by protective system, it could deteriorate the power quality accompanied with sag or flicker. Moreover, double circuit fault may lead to more aggravated situation, for instance, blackout. To Protect transmission lines from lightning stroke, reduction of tower footing resistance, multiple ground wires and unbalanced insulation in double circuit lines have been adopted. In this paper, we would like to introduce insulation design standards for lightning protection of Korea Electric Power Corporation.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.365-367
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• 2001

We are explaining shapes factor of ground electrode in a rectangular parallelepiped which is based on analysis of a hemisphere electrode. Actually, a hemisphere electrode is hardly used in a plan and construction, because it is difficult for somebody to use one. This thesis describes the method of grounding resistance estimation which is used the water tank model and electrode shopes factor.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.194-198
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• 2008

The necessities of development of foundation having minimized occupying area and construction time are required for overpass in the downtown area by which bimodal tram will pass a crossway. We are studying a single column drilled pier foundation which is continuous from pier to pile foundation. Due to the increased resisting moment by reinforced steel which is ranged from the upper part of pile to lower part of column above ground, it can be possible to make a smaller pile-section and lessen the bar reinforcing. And for the excavation work is possible with smaller equipment, this foundation has a improved constructability and economical efficiency. This foundation needs smaller amount of concrete and has a small self-weight. It has an effect on improving resistance against earthquake due to improved ductility in addition to improved rigidity by interaction between concrete and steel.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.2
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• pp.53-58
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• 2004

In this paper, the low-phase dual-band VCO, by adding switching circuit with PIN diode at feedback loop of the oscillation part having negative-resistance, is realized. In order to reduce the phase noise of the VCO, PBG structure applied to the ground plane of the resonator. When applying for PBG structure, output power is -9.17㏈m and phase noise is -102㏈c/Hz at 5.25㎓, output power is -5.17㏈m and phase noise is -101㏈c/Hz at 1.8㎓, respectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1014-1021
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• 2008

Ground anchor should not be used in soft clay, because anchor resistance can not be guaranteed. However, there is a way to increase the capacity of anchors. The pulse powered anchor is an underreamed anchor by using high voltage electrokinetic pulse energy. In this paper, conceptual introduction of the pulse powered anchor was presented. Anchor pull-out tests were performed at the Geotechnical Experimentation Site at Sungkyunkwan University in Suwon, Korea. Data were analyzed in order to verify the performance of pulse powered anchors.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1354-1359
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• 2009

Ground anchor should not be used in soft clay, because anchor resistance can not be guaranteed. However, there is a way to increase the capacity of anchors. The anchor is an underreamed anchor by using high voltage electric discharge energy. In this study, a series of field test were carried out in order to find ultimate load of underreamed anchors in weathered soil at the new apartment construction site located in Inchon, Korea. Data were analyzed in order to define a relation between ultimate load and the number of electric discharge.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.39-41
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• 2003

In this paper, we examine theory of literature announced recently. At the same time. analysis a special quality of the Grounding Plate Electrodes that is laid under the ground to homogeneity earth by Dwight way that is announced in existing and then examined through analysis of theory Value and resistance Value of water tank model experiment Value.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.12
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• pp.1944-1947
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• 2012

In this work, we investigated quench characteristics of matrix-type superconducting fault current limiters (MFCLs) according to the turn number of reactors. The reactors used in MFCLs apply magnetic field to superconducting elements within reactors when fault currents surge into MFCL systems. It makes the fast and simultaneous quenches between superconducting elements. Also reactors decrease the fault power burden of superconducting elements by bypassing the partial fault currents to itself, when quench occurs. These structure proposed in this work can be expected to achieve much more current limiting capacity even though it uses less superconductors compared with other type SFCLs. Three reactors were made by Bakelite. These reactors with the turn number of 190, 380 and 570, had the length of 270 mm and diameter of 80 mm. We reported experimental results, including fault currents, fault voltages and resistance in superconducting elements according to the turn number of reactors. We confirmed that experimental results will be useful in next future plan for the real power grid.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.270-272
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• 2018

This paper proposes an open-phase fault control system using 3-phase neutral voltage. The proposed control system is designed as a new topology which uses the potential difference between neutral point and ground(G) of three phase. And the open-phase detection system is configured to three resistance devices(Y-wiring) of the same capacity to each line of three phase power source R,S,T. This paper also designs a mobile phone application for remote alarm of open-phase fault.