• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.298-302
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• 2005

This paper presents the protection effect of SPDs according to installation conditions. To develop the effective protection countermeasures of information and communication equipments against lightning surges, actual-sized experiments in relation to the protection effects on the installation positions of surge protective devices(SPDs), the length of branch circuit the materials and long of conduit were conducted. The best method for protecting the electronic equipments from surges is to install the SPD at the front point of the devices to be protected. The installation method of the metal conduit bonded with common ground conductor were more effective than that of the PVC conduit.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1148_1149
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• 2009

반사형 전동 블라인드는 BEMS(Building Energy Management System)에 이용되는 조명 에너지 절감 장치로서, 블라인드 날개를 반사형 재질로 제작하여, 외부 채광이 블라인드 날개에 반사되어 천장에 반사되고 반사된 빛은 천장에서 확산되어 실내 깊숙이 부드럽고 균일한 조도를 공급해 준다. 이를 이용하면, 실내 거주자의 불편함 없이 실내 인공조명 사용량을 줄일 수 있다. 이를 구현하기 위해서는 태양광선의 고도의 변화에 따라 블라인드의 제어 각도를 계산하여 블라인드 제어 전동 모터를 구동해야 한다. 따라서 본 논문에서는 외부 채광을 실내 천장 면에 균일하게 반사할 수 있는 블라인드 날개의 제어 각도의 최적 조건을 제시하고, 컴퓨터 시뮬레이션을 통해 제시한 블라인드 날개 각도의 최적성을 검증하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.3
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• pp.69-74
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• 2007

Flux level is low in the maximum efficiency control of a stator flux-oriented control of induction motor under the light load. In this cast if the loaf torque is suddenly increased, torque component current is limited to the low level by torque-limit condition because of the low flux level. In this paper, a technique to solve the problem is proposed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.1
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• pp.50-58
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• 2011

In this paper, potential distribution analysis through the six kinds of case studies examined in the environmental conditions change within a limited space, by the power supply system installed. To interpret the potential distribution using electromagnetic field analysis program and the parameters were state of the ground, the outer wall of the configuration state and the presence of human potential distribution was simulated. Potential distribution analysis, the size of nominal voltage, depending on the impedance of human body to be determined on the impact of surprise decision, but if equipped with appropriate protective equipment can be protected from lightning have been confirmed.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.72-74
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• 2011

최근 IT 기술이 융합된 지능형 자동차 기술에 대한 관심이 높아짐에 따라 이에 대한 연구가 활발히 진행되고 있다. 차선 검출은 지능형 자동차의 주요 과제인 첨단 안전자동차 기술의 핵심적인 부분으로 국내외에서 다양한 방법들에 대한 연구가 진행되었다. 차량의 안전을 향상시키기 위해서는 충분한 제동거리 확보가 가능한 거리까지 정확하고 빠른 차선 검출이 이루어져야 한다. 기존의 경계선 검출기법들은 조명 변화에 따라 그 성능의 변화가 크게 발생하였다. 이는 차선과 도로의 사이의 값의 차이가 조명 조건에 따라 변하기 때문이다. 따라서 본 논문에서는 영상 분석을 통하여 경계선을 판단하는 값을 조절함으로써 환경에 적응적인 경계선 추출 방법을 제안한다. 차량 주행 영상에서 제안한 방법과 기존의 경계선 검출 기법을 적용하여 성능을 비교한다.

• Journal of Institute of Control, Robotics and Systems
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• v.1 no.2
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• pp.105-111
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• 1995

This paper proposes a segmentation algorithm using gray-level discontinuity and surface reflectance ratio of input images obtained under different illumination conditions. Each image is divided by a certain number of subregions based on the thresholds. The thresholds are determined using the histogram of fusion image which is obtained by ANDing the multiple input images. The subregions of images are projected on the eigenspace where their bases are the major eigenvectors of image matrix. Points in the eigenspace are classified into two clusters. Images associated with the bigger cluster are fused by revised ANDing to form a combined edge image. Missing edges are detected using surface reflectance ration and chain code. The proposed algorithm obtains more accurate edge information and allows to more efficiently recognize the environment under various illumination conditions.

• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.35-43
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• 2004

Illuminance and luminous levels in a small office space due to daylight were calculated to analyze the impact of daylight on contrast and lighting energy savings. Computer simulations were performed for four blind conditions under a clear sky condition. The blind conditions significantly impacted the illuminance an4 luminance level. Visual performance scores were calculated according to the transfer function that uses absolute contrast between target and background surface. The blind condition that had 45 tilted angle toward ground provided good contrast and performance scores. Using a control algorithm of an automated daylight dimming control system lighting energy sayings were predicted. For all blind conditions minimum lighting energy was consumed.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.38-39
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• 2009

친환경, 신 재생에너지 중 하나인 태양광은 크게 발전용과 조명용으로 사용될 수 있다. 자연채광시스템에 주요부품인 태양광을 전달하는 자연채광용 유리광섬유를 국내최초로 개발하였다. 적용된 자연채광시스템에 대해 소개하고 광섬유와 광케이블의 기본구조, 광학적 특성, 벤딩조건에 따른 조도변화 및 스펙트럼을 분석하였다. 조명용 뿐 만 아니라 식물성장용으로도 사용가능하여 지하농원 등의 적용이 가능하다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.1
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• pp.80-86
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• 2005

This paper proposes a design method of PID controller for achieving the desired specifications in the frequency domain via the reduced model of a high-order model with time delay. The proposed method identifies the parameter vector of PID controller from a linear system that develops from rearranging the two dimensional input matrices and output vectors obtained from the frequency bounds. Four examples are given to illustrate the feasibilities of the suggested schemes.

• Journal of the Korean Society of Safety
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• v.15 no.1
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• pp.167-175
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• 2000

Work performance and human error are complicated phenomena so that it is very difficult to grasp the true nature of them. However, Event Related Potential (ERP) may give a clue to them because human brain reflects diverse psychophysiological process. In the present study, the possibility of ERP application to the ergonomic area was evaluated in view of grasping error symptoms. For that purpose, the subjects were asked to count specific characters in a random character matrix on a computer monitor, and their ERP was compared with their performance data. Based upon the results, the amplitude of P300 was not so high as that in the case of the Odd Ball tasks, correct response corresponded with stable ERP with high P300 amplitude whereas wrong response did with unstable, fluctuating ERP with low P300 amplitude. Those results coincided with the work performance, and it was concluded that 3-wave fluorescent with illumination level of 800 lux would be recommendable for the counting task in concern. Conclusively, ERP including P300 might supply an objective clue to the problem of human errors in cognitive process.