• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.8-17
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• 2015

This paper analyses the power flow of a three-feeder/multi-bus distribution system by a custom Generalized Power Quality Conditioner (GUPQC). The GUPQC has been realized by three voltage source converters (VSCs) coupled back-to-back through a common DC-link capacitor on the DC-side. One feeder was controlled by the shunt compensator, whereas each of the other two feeders was controlled by the proposed novel series compensator. The GUPQC has the capability to simultaneously compensate voltage and current quality problems of a multi-bus/three-feeder distribution system. Besides that, the power can be transferred from one feeder to other feeders to compensate for poor power quality problems. Extensive simulation studies were carried out by using MATLAB/SIMULINK software to establish the ability of the GUPQC to improve power quality of the distribution systems under distorted supply voltage conditions.

• 한국정밀공학회지
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• 제19권7호
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• pp.116-124
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• 2002

The planning of part feeder and other manufacturing automation equipments is almost always underestimated. Planning ahead for those crucial pitfalls can permit steps to take to minimize heir impacts, especially if the problems can be discovered in the planning phase, not on the shop floor. Planning process is an engineering process, namely a series of trade-offs. The effective trade-offs in the shortest amount of time can be possible with the help of a computer-aided ngineering (CAE) technique. The main parts of CAE fur part feeder are database system of fabricated workpiece parts, part feeders, part feeder components. In this study, a planning process of part feeder is presented. Especially, a systematic analysis of workpiece parts and part feeders is performed for the design of databases of CAE system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1156-1158
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• 1998

This paper Presents two distribution-feeder models to simplify complicated distribution system calculations. These equivalent models are developed to simulate the total series voltage drop at the end of the given feeder and the total line loss of the given feeder accurately. In addition, the proposed models are bidirectional. This means that power infeed can be at either end and the model is accurate. Also, it is shown that the proposed models are suitable for network reconfiguration.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.275-280
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• 1990

A neural network method is applied for recognizing the orientation o f individual parts being fed from a bowl feeder. The system is designed in such a way that a part can be discriminated and sorting according to every possible stable orientation without implementing any a mechanical tooling. The operation of the bowl feeder is based on a 2D image obtained from an array of fiber optic sensor located on the feeder track. The acquired binary image of a moving and vibrating part is used as input to a neural network which, in turn, determines t he orientation of the part. The main task of the neural network, here is to synthesize the appropriate internal discriminant functions for the part orientation using the part features. A series of the experiments reveals several promising points on performance. Since the operation of the feeder is highly programmable, it is well suited for feeding and sorting small parts prior to small batch assembly work.

• Korean Chemical Engineering Research
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• 제52권3호
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• pp.366-370
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• 2014

태양전지의 전력향상을 위해 외부에 연결된 시스템적인 접근방법으로써 가변병렬공급기(DC1)와 가변직렬공급기(DC2)가 부착된 전자 전달 증대기(Electron Relay Enhancer: ERE)를 이용한 연구를 수행하였다. DC1의 전압이 태양전지 전압보다 높을 경우 DC1은 저항과 같은 역할을 하므로 태양전지의 전압이 상승하게 되고 반면 전류는 낮아지게 된다. 이 때 낮아진 전류는 DC2에서 보충해주어 태양전지의 출력이 증가하게 된다. DC ERE 직-병렬 시스템은 병렬전압의 1.5~2.0 V 증가로 태양전지의 전압을 2.0~3.0 V 높일 뿐 아니라 전력 증가율도 약 10% 정도 향상시켰다.

• Journal of Biosystems Engineering
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• 제32권5호
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• pp.292-300
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• 2007

Not many types of roughage cutters have been introduced in Korea so far. However, those machines could not satisfy farmers to cut rice straw or barley wrap-silage properly. Stiffness and firmness of roughage bale were two obstructing factors. In order to solve this problem, a tractor attached cut-feeding machinery for the round baled roughage was developed for dairy and beef cattle farm in Korea. A series of tests were performed and acquired data were analyzed by using the several imported roughage cutters, which have been already introduced in dairy farm in Korea. And, a prototype of forage cutter was selected, analyzed, designed and manufactured to develop a tractor attached roughage cut-feeder for round bale. Also, the prototype machine was tested, modified and improved through revising model. As a result, a tractor attached roughage cut-feeder for round bale was manufactured. In order to evaluate the performance of the model machinery. a series of test were performed by the prototype machinery both at the plant and field. The model machinery developed satisfied in both power requirement and cutting capacity. As a conclusion, one of the obstacles against feeding the round baled roughage in the korea cattle farm can be eliminated by developing the tractor attached round baled roughage cut-feeder.

• 전기의세계
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• 제22권6호
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• pp.8-18
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• 1973

This paper is a part from the series study on the 22.9KVY multiground destribution system and its is divided into three parts as follow. A.C. Network Analyzer study on the load current flow when one phase line of the feeder is out of seroice because of cutting. A.C. Network Analyzer study on the increasing zero sequence current in the good feeders when one feeder is under fault of single phase short. Field test report of the common use of open telephone line on same poles of 22.9KVY distribution system.

• 산업경영시스템학회지
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• 제29권1호
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• pp.63-71
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• 2006

In this paper, we consider a planning problem arising from printed circuit board manufacturing industries. Given a set of several types of PCBs, component feeders and surface mounting machines in series in a PCB assembly line, the problem is to define the feeder allocation and job sequence with the objective of minimizing the total operation time of the line. We formulate the problem as a mathematical model. And, the problem is proven to be NP-hard, so a genetic algorithm is developed. Finally, we give test results to evaluate the performance of the genetic algorithm.

• 한국항해항만학회지
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• 제36권5호
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• pp.409-418
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• 2012

컨테이너 선사들은 세계경제의 불황과 고유가가 지속되고 있는 상황에서 선박운영비용을 낮추기 위한 다각적인 노력들을 전개하고 있다. 이러한 상황에서, Grand Alliance는 극동 북미서안 서비스인 CCX와 극동 북미동안 서비스인 NCE에 서비스별 선박추가 투입대신에 Dedicated Feeder 투입을 하기로 결정하였다. 즉, 기간항로의 선박이 북중국항만에 기항하지 않고 환적항인 부산항에서 Feeder선을 통하여 환적 운송하게 된다. 본 연구에서는 전용피더 서비스 도입을 통한 환적의 경제성 효과를 확인하기 위하여 Grand Alliance 컨테이너 서비스의 실제 운영 자료에 대해 분석하였다. 이와 같은 전략을 통해 Grand Alliance의 'NCE, 'CCX'항로는 기간항로에 투입되는 선박의 감속운항이 가능하게 되어 선박 운영비의 절감 효과를 보이고 있다.

• 한국통신학회논문지
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• 제21권2호
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• pp.495-504
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• 1996

본 논문에서는 슬롯결합 급전구조를 갖는 직렬급전 마이크로스트립 배열 안테나의 정확한 해석 및 설계방식을 제시하고 그 특성을 분석하였다. 슬롯결합 급전구조의 정확한 해석은 급전선에서의 진행파 모드와 비진행파를 모드를 모두 고려하는 full-wave방법과 안테나간의 회로적인 결합을 이용하여 해석하였다. 수치해석에 사용된 기저함수는 해의 수렴도, 정확도 및 계산시간을 비교하여 패치는 3개의 EB모드, 슬롯은 1개의 PWS모드, 급전선은 5개의 PWS모드를 사용하였다. 이러한 안테나 해석을 바탕으로 직렬급전 배열 안테나가 정재파형 구조로 설계되었다. 정재파형 구조에서 각 소자의 여기량을 조절하는 설계방식으로는 슬롯의 길이를 변화시키는 방식과 슬롯과 급전선과의 이격거리를 변화시키는 방식을 사용하였다. 본 논문에서 사용한 이론을 이용하여 8소자 Cheyshev배열 안테나를 설계하여 실험한 결과 슬롯과 급전선간의 이격거리를 조절하여 설계하는 방식이 각 소자간의 공진 주파수의 변화가 없으므로 슬롯의 길이를 가변시키는 방식보다 설계가 간편함을 알 수 있었고, 측정 결과도 우수하게 나타났다.