• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1238-1240
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• 1998

For economic operating of distribution system, utility has to minimize the loss in distribution line by controlling reactive power and power factor. This paper presents calculation of reactive power in distribution line, estimation of the condenser capacity according to distance, and computation of optimal location and proper condenser capacity.

• 한국전자통신학회논문지
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• 제10권4호
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• pp.491-497
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• 2015

본 논문에서는 능동형 RFID 방식의 태그와 리더로 구성된 대기 전력 제어 모듈을 설계하고 구현한다. 태그와 리더는 C8051 MCU와 CC2500으로 구성된 RF모듈을 내장하고 있으며 리더에는 대기 전력 제어 콘센트가 부착되어 있다. 리더는 송신 패킷 인식 여부에 따라 릴레이를 제어한 후 전원 공급을 차단하여 대기 전력으로 소비되는 전력을 감소시키며 저 전력 패킷 예측 알고리즘이 적용되어 태그와 리더의 전력 소모를 낮추었다. 실험 결과, 리더의 패킷 송, 수신 여부에 따라 대기 전력 제어 콘센트의 릴레이를 동작시켜 대기 전력을 제어할 수 있음을 확인하였다. 또한 RSSI값에 따라 태그와 리더 사이의 동작 거리 설정이 가능하며, 콘센트의 대기 시간 동안 리더에서 작동하는 수신 Duty Cycle을 설정함으로써 리더에 소모되는 전력을 절감할 수 있음을 확인하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제27권3호
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• pp.1-24
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• 2018

Purpose The purpose of this study is to attempt to incorporate power theory to evaluate information capability of SCM adopters. Therefore, this study focuses on the relationship of information sharing, partnership quality, and information capacity according to the power intensity of the variables of SCM. and CSV value creation. Design/methodology/approach The questionnaire of SCM builder was conducted and 302 samples were analyzed. Based on the theoretical background of power and information capacity, we set up a structural equation model. Hypothesis testing and statistical analysis were done through AMOS and SPSS. Findings First, it shows that the compensation power among the constrained power has a positive effect on the partnership quality, and the legitimacy power has the positive influence only on the information sharing. Compulsive power, compensation, and legitimacy, which are generally restrictive powers, may reduce the quality of information sharing and partnership, but the results of this study are rather higher. Second, both non-binding power expertise and criterion have a positive effect on information sharing and partnership quality. Third, information sharing has a positive effect on partnership quality. Supporting a number of research results, it is well reflected in SCM attributes where interdependence is important. Fourth, information sharing and partnership quality have a positive effect on information capacity. Information literacy has become an essential element in modern management. Fifth, the enhancement of CSV value creation plays a role of a controlling variable to further strengthen information sharing through non - binding power attribute, expertise and conformity. In addition, the strengthening of CSV value creation has been shown to play a role as a controlling variable to further strengthen the quality of partnership through the non-binding power attribution, but expertise has been rejected.

• Journal of Power Electronics
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• 제5권2호
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• pp.166-172
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• 2005

The basic equations of a doubly-fed long-stator linear motor for a shuttle-based railway system are established. They show which degrees of freedom exist for controlling the motor. The ratio of stator and rotor current proves to be an important parameter in determining the design of motors, converters and mechanics.

• 한국농공학회지
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• 제14권3호
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• pp.2697-2702
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• 1972

Controlling insects and diseases is an important factor for increasing yields of agricultural products. Power sprayer is widely used in cooperative controlling of insects and diseases for the production of rice and fruits. However, farmers need a long hose to use the power sprayer and that presently most of the farmers have hose made abroad. This study was designed to test the change of outside diameter and unit Iength, and to measure the pressure Ioss for three different kinds of hoses made domestically and one made in Japan. The resulte are as follows; 1. The three kinds of Korean-made hoses showed an increase in the length and a decrease in the outside diameter as the spraying pressure increase. The rate of change of the length ranged from 3.5% to 1.6% and the rate of change of the outside diameter from 3.5% to 1.4% respectively. 2. As the length of hose increases, the pressure loss was $3kg/cm^2$ at the end of a 100m of the hose made in Japan, while it was $7-10kg/cm^2$ for Korean-made hoses. 3. The Korean-made hoses were not broken under $27-28kg/cm^2$ of spraying pressure. 4. As a conclusion, the Korean-made hoses can safely be used under continuous rated pressure of the power sprayer, but they can not properly be used for the case of cooperative controlling system where a long hose is reguired because of the heaviness of the hoses and the narrowness of the inside diametar. Hence, it is highly recommended to improve the Korean-made hoses to be used for such a situation.

• 한국정보통신학회논문지
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• 제24권7호
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• pp.914-924
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• 2020

본 연구에서는 소셜 네트워크를 생성 할 수 있는 인공적인 네트워크 발생 모델을 제안 하였다. 본 연구에서 제안한 발생 모델은 온라인 소셜 네트워크의 특징인 Small-World 성질과 Scale-Free 성질을 단순하게 표현하는 것에서 벗어나 모델의 두 파라메터를 적절히 조절함으로서 사용자가 원하는 다양한 위상 특성치 값들을 나타내 줄 수 있도록 하였다. 이를 위해 Preferential Attachment의 세기를 조정 할 수 있도록 파라메터 K와 군집화 계수를 적절하게 조정 할 수 있도록 파라메터 P를 도입하였다. K가 0에서 10 그리고 P가 0.3에서 0.5 사이의 조합이나 K = 0과 P = 0.9를 이용하면 소셜 네트워크의 위상적 성질을 보유하는 인공적인 네트워크를 생성할 수 있다. 이 조합 하에서는 Small-World 성질과 Scale-Free 성질이 잘 나타난다. 노드차수 분포는 Power-Law를 따른다. 또한 군집화 계수 0.130 ~ 0.238, 평균 최단거리 5.641 ~ 5.985로 나타났다. 또한 네트워크의 크기를 노드 5,000개에서 10,000개로 증가시켜도 소셜 네트워크 성질을 그대로 유지하는 것으로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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• pp.214-218
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• 1991

This paper presents a PWM controlled cycloconverter with a DC resonant circuit for Induction heating. This cycloconverter converts commercial frequency power to high frequency power directly. So conversion efficiency improved. Controlling a input reactive power regardless of load power, it has sinusoidal input current waveforms as well as a input. displacement factor at 1.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.283-286
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• 1990

This paper presents a PWM controlled cycloconverter with a LC resonant circuit for induction heating. This cycloconverter converts commercial frequency power to high frequency power directly. So conversion efficiency improved. Controlling a input reactive power regardless of load power, it has sinusoidal input current waveforms as well as a input displacement factor at 1.

• 대한전기학회논문지
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• 제32권3호
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• pp.76-83
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• 1983

This paper describes the method of operating the phase controlled rectifier by controlling the firing angle in III, IV quadrant to absorb the lrading reactive power and of improving the waveform of ac current by driving dual converter. The system is intended to compensate the reactive power for any lagging load. Also, by the above method this paper enables us to improve the power factor and waveform referred to the source current and the dc output voltage in the converter.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.195-198
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• 1996

The control objective of drum level of boiler in thermal power plant is to maintain drum level at constant setpoint regardless of disturbance such as main steam flow. The initial response of the drum level loop process is in a direction opposite to the final response. The drum level loop shows inverse response when the power is changed abruptly. We adopt fuzzy controller using knowledge base considering system dynamics for controlling drum level. Finally, the simulation result using the digital simulator for boiler system in Seoul Power Plant Unit 4 shows the validity of fuzzy controller.