• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.913-915
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• 1996

This paper proposes the proper phase arrangement of transmission lines for reducing the zero sequence circulating current. It is a well-known fact that the zero sequence circulating currents are principally caused by the untranposed lines and numerical estimation method already has been established. In this paper, the circuit analysis for calculating the zero sequence circulating currents was performed on the existing 154kV four-circuit systems of KEPCO and the proper phase arrangement was determined.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1678-1680
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• 2005

This paper presents Building Integrated Photovoltaic system of the balcony type which is influenced by conditions such as irradiation, module temperature, shade and array arrangement. When architecture component, trees and cloud shade connecting array in series, total PV array current is reduced. So, before PV system design, a planner have to simulate many situations. And then array should be composed suitable for parallel and series modules. By the results, it is very important to develop optimal design of array considering shade effect for the balcony PV system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.84-87
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• 2005

This study is aimed to compare the insertion losses of periodically folded barriers which have same folded width, depth and period of arrangement but different direction of arrangement. One is vortical to the roadside and another is parallel. The pressure levels and the insertion losses at the receiving points behind finite length barriers are measured in an anechoic room by scale model test. The measured insertion losses are compared with calculated insertion losses by 3D BEM models.

• Radiation Oncology Journal
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• 제7권2호
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• pp.313-320
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• 1989

고주파유전가열 장치는 심부까지도 효과적인 가온이 가능하여 각족 심부암의 치료에 응용되고 있다. 그러나 한쌍의 전극을 평행으로 대칭 배열하는 현재의 방법은 신체의 일측으로 편재되어 있는 병소에는 배열 자체가 불안정할 뿐만 아니라, 노출된 동측 피부표면이 과열되며 종양의 가온 양상도 만족스럽지 못한 경우가 많아서 임상 적응에 난점으로 지적되고 있는 실정이다. 저자들은 상기와 같은 병소를 보다 안전하고_도 효과적으로 가온하기 위하여 두 전극간에 일정한 각도를 이루는 새로운 전극 배열을 시도하였다. 즉, 임상 적용 가능성을 고려한 $60^[\circ},\;90^{\circ}\;및\;120^{\circ}$로 전극을 배열하고 모형 (phantom)에서 가온 실험을 행하여 이같은 각도 배열에서의 온도 분포의 특성을 평가할 수 있었고, 일측에 편재된 병소를 가진 3예의 환자에게 각도 배열로 온열치료를 시행한 결과 환자의 수용성, 부작용 및 온도분포에 있어서 만족할 만한 결과를 얻을 수 있었다. 따라서 저자들이 시도한 전극의 각도배열은 일측에 편재된 병소를 유전 가열 장치로 가온 할 때 평행 배열이라는 한계점을 극복할 수 있는 새로운 방법으로서 매우 고무적으로 생각된다.

• 조명전기설비학회논문지
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• 제21권9호
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• pp.32-38
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• 2007

In this study, a new algorithm for measuring the velocity and distance from a camera to a moving object by using pseudo-stereo images obtained from a single camera with a stereo adapter is proposed. The proposed system is similar to a parallel visual stereo system using a two-camera system, but because this system can obtain pseudo-stereo images form a single camera, it has advantages not only in the aspect of cost but also in stereo conformity by arrangement and the calibration of the left and right stereo cameras upon image processing.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권7호
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• pp.362-368
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• 2006

This paper presents the results of a small capacitive current interruption test for the three types of interrupter which are called 'serial type', 'parallel/separated type' and 'puffer type' according to the arrangement of the thermal expansion chamber and the puffer cylinder. After the preconditioning test the small current interruption capability of the 'puffer type' decreased, on the contrary, that of the hybrid interrupters increased. A number of reignition have been occurred in the 'serial type' hybrid interrupter and the change of small current interruption capability after preconditioning test is mainly influenced by the structure of interrupter. Finally it has been proved that the 'parallel/separated type' hybrid interrupter has the best interruption performance through the verification tests.

• 한국초전도ㆍ저온공학회논문지
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• 제18권2호
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• pp.30-36
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• 2016

For the magnetic field analysis or design, it is important to know the behavior of the magnetic field in an interesting space. Magnetic field mapping becomes a useful tool for the study of magnetic field. In this paper, a numerical way for mapping the magnetic field within the cylindrical center volume of magnet is presented, based on the solution of the Laplace's equation in the cylindrical coordinate system. The expression of the magnetic field can be obtained by the magnetic flux density, which measured in the mapped volume. According to the form of the expression, the measurement points are arranged with the parallel cylindrical line (PCL) method. As example, the magnetic flux density generated by an electron cyclotron resonance ion source (ECRIS) magnet and a quadrupole magnet were mapped using the PCL method, respectively. The mapping results show the PCL arrangement method is feasible and convenience to map the magnetic field within a cylindrical center volume generated by the general magnet.

• 전기학회논문지P
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• 제50권3호
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• pp.117-124
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• 2001

The aim of this paper is to develop a controller of multi-phase bipolar brushless DC (MPB BLDC) motors for an electric bicycle. A MPB BLDC motor has a Permanent magnet rotor in which the magnetic arrangement is radial to the shaft and integral to the rotor laminations. This technique concentrates flux, giving a higher flux density than a surface-mounted PM motor and increases reluctance torque. The stator of MPB BLBC motor has parallel winding, allowing multi-phase separate independent controllability. It gets much more high power than wye-connection at same low voltage. The conventional techniques of exited with modulation(EWM), bidirection control, and partial square wale control are Proposed with one H-bridge and two photo sensors per phase. The Proposed controller is satisfied for the limited speed control and designed for system stability Experimental results show the performance of the proposed controller of MPB BLDC motors for an electric bicycle.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권9호
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• pp.408-413
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• 2005

This paper presents the basic design technology on the hybrid type GCB(gas circuit breakers) through the test results. The three type hybrid interrupters according to the arrangement of the thermal expansion chamber and the puffer cylinder(they are called 'serial type', ' parallel/exchanged type ,' and ' parallel/separated type ' respectively in this work) were designed and manufactured and then the tests of operating characteristics and interrupting were performed using a simplified synthetic test facility. The interruption capability with the type and the opening speed and the pressure rise which is required to interrupt were examined. The change of pressure rise with the number of interruption was given quantitatively and therefore the pressure rise can be predicted. Finally, it was shown that the interruption capability tends to increase with the increasing of opening speed in the puffer type; however, the hybrid type interrupter has a different interruption characteristic.

• 전기학회논문지
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• 제60권3호
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• pp.544-551
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• 2011

This paper presents the circuit arrangement and effective control method of regenerative energy storage system for an electric vehicle using super-capacitors as the braking energy storage element. A bi-directional controlled current flow of the DC-DC converters with the capacitor bank is connected in parallel with battery, and is controlled so that the whole of the braking energy is effectively absorbed into the capacitors and released back to the electric motor upon acceleration. The converter needs the series-parallel switching circuit for making the best use of the series capacitors and for limiting the step-up ratio of the boost converter. The proposed methods are verified by computer simulation and experimental set-up. They are usefully applied to the electric vehicles such as green cars, electric motorcycles, bike, etc which are power- supplied by the electric batteries.