• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.6
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• pp.57-63
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• 1997

Uninterruptible power supply(UPS) system should provide a good quality and stable power supply no matter what the condition of the raw mains. And when the mains fails, it must provide uninterrupted power to the load for a specified time. In this paper. discrete control system is introduced to improve output waveforms of UPS. This technique can be obtained output voltage by discrete data of synchronous control and voltage control to various loac. And then, the compact and light UPS can be realized by remove of the analog circuit and simulation and ezperinentation were performed with this control algofihtm. The experiment result show the effectiveness of proposed UPS system uwing the discrete control techjique.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.2
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• pp.89-93
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• 1997

As industry gets rapidly automatic, D.C servo motor which is controlled by a PI controller needs accurate control. However, when a system has various characters, it is very difficult to guarantee its accuracy. In this paper, rule-based auto-tuning PI controller for motor speed control system is presented as a way of solving this problem. Some rules are based on Ziegler-Nichols step response and expert knowledge. Control parameters are determined by error, slope, steepest slope point, and permiSSIon overshoot. The accuracy of control is demonstrated by a computer s mulation .

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.36-48
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• 2008

This study examines the influence of control algorithms on dimming performance to determine appropriate control setting when direct/indirect lighting is controlled by a daylight dimming system. Computer simulation were performed for a small office with double skin envelope under various daylight conditions. A retractable fabric shading and Venetian blind were applied for internal and external envelopes under three CIE standard sky conditions. Unshielded and partially-shielded photosensors were used, and three control algorithms were applied for the sensors. In general, dimming level was too excessive due to the direct impact of light from lighting fixture to the photosensor. Providing insufficient lighting output, the unshielded photosensor completely failed to secure required illuminance under any daylight condition. When a partially-shielded photosensor was applied under clear sky, three setting points functioned effectively. Less sensitivity for the partially-shielded photosensor was effective to control the dimming system optimally with reasonable energy saving. However, the daylight dimming control system for direct/indirect lighting does not appear to be energy effective when photosensors without enough shielded area is installed on ceiling where light from fixtures reaches directly.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.199-201
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• 2007

This paper presents the installation of measuring system for the transient behaviors of grounding system impedances using portable impulse current generator. The measuring system is controller, with controller, power supply, impulse current generator and data aquisition system. In the evaluation of the impulse response in a ground electrode, the step response is calculated based on the ratio of the voltage and current observed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1990.10a
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• pp.57-62
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• 1990

This paper describes the development and testing of a degitial controller for heat-ing ventilating and air-conditioning system. The controller uses properational-integral control action and self tunes to provide the Zigeler-Nichols when given a step input. The algorithm has been simulated fas static pressure.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.951-952
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• 2012

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1992.11a
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• pp.64-68
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• 1992

The demand for home automation system has increased in high-rise apartment houses. Home automation system is realized a more comfortable, more secure, more economical, more convenient, and more satisfying home life. The proposed system functions are meter reading, home security, energy saving, and house control. The technical requirements and configuration of home automation system are provided.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.205-206
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• 2005

태양 전지를 이용하여 정원등의 시스템을 구성하면 환경 친화적이면서도 에너지 절감의 큰 효과를 얻을 수 있다. 또한 기존의 정원등은 수은등을 사용하기 때문에 전력 소비가 많은 반면, 고휘도 LED를 사용한 정원등은 전력소비를 줄일 수 있는 큰 장점을 가지고 있다. 본 논문에서는 간단한 회로 구성과 CDS센서를 이용하여 실제적인 회로 설계를 하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.42-43
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• 2005

열악한 환경과 점검이 곤란한 장소에 설치되는 전자식안정기용 원격 감시와 제어 시스템을 RF를 사용하여 설계 제작하였다. 본 연구에서는 시제품을 개발하여, 안정되게 동작함을 확인하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.115-118
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• 2001

본 논문에서는 역률 개선용 제어 IC를 사용하여 고압나트륨램프의 역률을 개선시킨 전자석 안정기를 제안하였다. 또한 인버터 회로를 설계하여 시동전압의 과도특성을 해석하였으며, 전원측에 EMI 필터를 설계하여 전자식 안정기 시스템을 보호하였다. 자기식 안정기와 전자식 안정기에 대한 역률, THD 및 광속 등의 전기적 특성을 비교 측정하였다. 제안된 고압나트륨램프용 전자식 안정기의 출력을 측정한 결과 역률은 99.9[%], THD는 4.51[%]로 나타났다.