• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.10
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• pp.1744-1751
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• 2008

This paper presents a monitor positioning algorithm to identify the power quality event source in the distribution system with distributed generations. This algorithm determines the appropriate number of monitors and their locations considering power system topology together with distributed generation. This paper summarizes the guidelines of monitor positioning into five principles and defines the weighting factors according to the principles. To evaluate the adequacy of monitor positioning results, ambiguity indices considering monitor location and system topology are proposed. The optimal number and locations of monitors are determined from optimization routine using the weighting factors and the monitor positioning results are evaluated in terms of ambiguity indices. The algorithm is applied to IEEE 13 bus test feeder and suggests the optimal number and locations of power quality monitors. The proposed approach can realize the expert's knowledge on monitor positioning into a sophisticated automatic computing algorithm.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.54-58
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• 2002

PID Controller is widely used as automatic equipment for industry. However, when a system has various characters, parameter decision and tuning for accurate control is a hard task. In this paper, expert auto-tuning PID controller using PLC is presented as away of solving this problem. Expert auto tuning algorithm is based on Ziegler-Nichols step response and expert knowledge. The test of control performance is carried out in practical speed control of Induction Motor in variable load, the experimental results suggest its superior performance.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.60-66
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• 2011

In the present investigation, experimental studies were conducted on the fire suppression performance of twin-fluid water mist spray which is subjected to thermal radiation in a closed space. Downward-directed water-mist sprays, interacting with an under kerosene pool fire, were investigated in a test facility. The mass mean diameter of water-mist droplets were measured by PMAS under various flow conditions. The developed twin-fluid water mit spray nozzle satisfied the criteria of NFPA 750, Class 1. The mechanism of fire suppression by fine water mist was concluded to be the cooling of the fire surface which leads to the suppression of fuel evaporation. It was proved that the automatic twin-fluid water mist spray system under lower pressures could be applied to an industrial facilities.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.117-121
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• 2001

This paper presents a new approach to the calibration of a SCARA robot orientation with a camera modeling that accounts for major sources of camera distortion, namely, radial, decentering, and thin prism distortion. Radial distortion causes an inward or outward displacement of a given image point from its ideal location. Actual optical systems are subject to various degrees of decentering, that is, the optical centers of lens elements are not strictly collinear. Thin prism distortion arises from imperfection in lens design and manufacturing as well as camera assembly. It is our purpose to develop the vision system for the pattern recognition and the automatic test of parts and to apply the line of manufacturing.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.11a
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• pp.325-328
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• 2009

지상파 DMB가 널리 보급되고, 이를 활용한 재난경보서비스가 시험방송을 준비 중이다. 그러나 검증되지 않은 수신기들이 대량으로 출시되어 BIFS 대란과 같은 문제점도 발생하였다. 재난경보방송은 정확한 정보 전달이 매우 중요하므로, 이와 같은 문제가 발생하지 않도록 하기 위한 '지상파 디지털멀티미디어방송(DMB) 재난경보방송 수신기 표준적합성 시험'을 두고 있다. 이 표준을 분석한 결과 추가되어야 할 시험 방목이 몇 가지 발견되었다. 이 논문에서는 '지상파 디지털멀티미디어방송(DMB) 재난경보방송'의 메시지 포맷을 분석하여 각 필드가 모순되는 경우와, 사용하지 않는 값이라 명시하였으나 시험 항목에 누락된 부분을 파악하여 보충하였다. 이러한 시험 항목을 이용하면 표준을 보완하고, 결함이 더 적은 수신기를 개발하는데 도움이 될 것이다.

• 한국항공운항학회:학술대회논문집
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• 2016.05a
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• pp.30-34
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• 2016

TR-60 틸트로터 무인기는 전장 3m, 최대이륙중량 200kg로서 2013년 2월 자동천이비행에 성공한 비행체로서 현재 해상운용을 위한 함상이착륙기술을 개발 중에 있다. 무인기 해상운용은 육상보다 심한 염무와 바람과 선박의 운동에 의한 착륙대의 이동 등의 열악한 환경에서 이루어져야 한다. 이동이 있는 착륙대와 착륙장 주변의 장애물을 고려하면 정확한 착륙을 위한 정밀한 항법유도가 요구된다. TR-60의 정밀항법유도를 위해서 수cm 단위의 정확도를 갖는 RTK GPS 기반의 정밀상대항법과 이동 착륙장 대한 자동착륙유도를 설계하고 구현함으로 함상자동 이착륙 기술을 개발하였다. 본 논문에서는 RTK GPS 기반의 정밀상대항법과 자동착륙유도에 대한 연구와 함상접근착륙절차에 따른 자동착륙정확도 측정 비행시험 결과를 기술하였다.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.3
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• pp.305-314
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• 2001

In this paper, we construct an automatic evaluation system of psychological feeling for corporate identity (CI) symbol mark based on a fuzzy neural network technique. The system is modelled by trainable fuzzy inference rules with several input variables (qualitative and quantitative design components of CI symbol mark) and a single output variable (consumer's feeling). The back propagation learning algorithm, which is a conventional learning method of multilayer feedforward neural networks, is used for parameter identification of the fuzzy inference system. The learning ability to train data and the generalization ability to test data are evaluated for the proposed evaluation system by computer simulations.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.28-33
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• 2010

Ni alloy steel is able to use during long time because of good acid and corrosion resistance. So, it's research has focused on developing the alternative alloy which is economically feasible. Recently, consumption of Kovar steel is gradually increased in field of the jet engine and the gas turbine because of its low thermal expansive characteristics. The specimens of Kovar steel(29%Ni-17%Co) contain 0.00%C, 0.03%C, 0.06%C, 0.10%C and 0.20%C, respectively. Ingots are manufactured by VIM(vacuum induction melting furnace) and then specimens are made by automatic hot rolling after heat treatment. Strength of Kovar steel according to carbon contents is estimated by hardness, tensile and impact test. Hardness of the 0.20%C specimen is more improved approximately 14.4% than one of base metal. Its strength increases 32.4% of a base metal, and its impact energy is also enhance 11.5%.

• Journal of Biomedical Engineering Research
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• v.12 no.2
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• pp.89-98
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• 1991

This study is concerned on the automation for cell diagnosis which has better objectivity and speed of test than human beings. Diagnosis is on the basis of shape change of abnormal Cells. Used parameters are nucleus area, nucleus perimeter, nucleus shape, cytoplasm area, nucleus/cytoplsm ratio, which was obtained using image processing technics. A new mode method is proposed on the automatic threshold selection for superior process time compared with Otsu's. Contour of the cytoplasm of abnormal cell is obtained using me- dian filter and sorel operator. The mask to get only original shape of abnormal cells is formed uslng the contour filling algorithm. In the result the normal cells are separated from the abnormal cells and the abnormal cells can be distinguished through screwing of abnormal cell's image with reference data to judge abnormal cells. Owing to this study the number of inspections which the pathologists should examine will be decreased and the time for inspection will be shortened.

• Journal of Satellite, Information and Communications
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• v.10 no.3
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• pp.16-21
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• 2015

In this paper, we presented Under Vehicle Inspection System by comparing two image signals. Two signals are generated by license plate number and under-vehicle pattern recognition. The test shows reliable precision within real-time of 2.8sec, which can be applicable commercially. In the future, more research will be conducted to enhance the precision by automatic image balance in many challenging situations.