• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.431-434
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• 1999

This paper presents design of controllers for battery energy storage system. The proposed battery energy storage system can be controlled to operate in the power conditioning mode or the inverter mode. The operation of this mode further divided into three cases: (a) in the peak load period, the load power supplied from the utility is minimized as far as possible; (b) in the off-peak load period, the utility supplies power to the load and charges the battery bank with automatic charging control; (c) in the medium load period, to save battery energy the real power flow out of the battery energy storage system is minimized. Besides, in all cases, the proposed battery energy storage system also automatically compensates the harmonics, subharmonics and reactive power factor in the utility side are much improved. Simulation results are presented by the effectiveness of the proposed controllers for battery energy storge system.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.250-253
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• 1989

As the necessity of increasing the midnight base load is extensively increased, electric power companies have to increase the demand of midnight electrical power by lowering the electrical charge rate at midnight. One of the most widely used midnight equipments is the heat Storage type's electrical boiler. A Single chip microprocessor controller for the heat-storage type's electrical boiler is developed. This controller call reduce the undesirable peak load at the begining of midnight (i.e.11 P.M.) time band by using backward load control method. Futhermore, this controller enables reservation of heat storge and the effective heating control the field test has been done by use the boiler for 66$m^2$ with the heater of 21KW quality.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.292-294
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• 2002

Load management programs was initiated in the 1970s to actively influence customer load in the United States. Generally, load management programs can be categorized into direct load control(DLC), indirect load control(IDLC), and energy storge system(ESS). The DLC allows the utilities to shed remote customer demand unilaterally Direct load control(DLC) has lately attracted considerable attention. This paper suggests efficient promoting plans of DLC, which has a lot of advantages. The importance of DLC will be increased more and more. Therefore, various studies of DLC activation plans have to be continued.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.6
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• pp.124-130
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• 1989

For the higher density DRAM'S, innovations in fabrication process and circuit design which have led to dramatic density improvement are discussed from the desinger's perspective. A new dynamic RAM cell called Trench Epitaxial Transistor Cell(TETC) using trench technics and SEG have been developed for use in future megabit DRAMS. Storge electrode with $n^+$-polysilicon and $n^+$-source electrode are self-contacted in TETC. With keeping the storage capacitance large enough to prevent soft errors, the cell size reduced to 30% compare with existing BSE cell by utilizing the vertical capacitor made along the isolation region.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.166-173
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• 2001

Recommended seismic design guide for the flat bottom vertical-cylindrical oil storage tanks in KS B 6225 is presented. Under earthquake excitations, the hydrodynamic pressure exerted on the tank walls produces overturning moment which may cause either a failure of the anchors or a buckling of the tank shell near its base. The basis for establishing design loads due to hydrodynamic pressure is described including seismic zone risk map in Korea, zone coefficients and the essential facilities factor. This procedure for calculating applied compressive stress on the shell base subjecting to seismic load and for estimating the allowable buckling stress is described.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.9
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• pp.727-735
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• 2003

The determination of completion time constitutes an important step in developing algorithms for short-term production scheduling. Existing completion time algorithms of multi-product batch processes often assume that intermediate storage tanks are always available when it is needed. In this paper, we consider a serial multi-product batch plants with ZW and NIS policy intermediate storge tank. We limit storage residence time and allocated products in the intermediate storage tank to minimize the quality change of the stored material as well as to reduce the clearing time during product change. A set of recurrence relations is suggested to calculate the completion times for the given batch sequence of products on all processing units. Also analytic solution for the suggested model is solved by a graphical method. The effectiveness of these results is proved by a few illustrative examples.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.6
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• pp.330-335
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• 1999

This paper proposed the p-q-r coordinate system where the instantaneous active power p, and the two instantaneous reactive powers qq, qr were defined. The three power components are linearly independent, so the compensation for the two instantaneous reactive powers leads to control the two components of the current space vector. With the theory, the neutral current of a three-phase four-wire system can be eliminated by only compensating the instantaneous reactive power using no energy storge element.

• The Optical Journal
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• s.112
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• pp.50-59
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• 2007

일본의 재단법인 광산업기술진흥협회는 각종 조사와 테크놀로지(Technology) 로드맵 사업을 기초로 국가적 레벨에서 산학연과 함께 다양하고 강력한 광관련 기술개발활동을 전개하고 있다. 협회는 2002년도부터 5년간에 걸쳐 진행한 "광(Photonic)네트워크", "고효율 유기디바이스", "대용량 광 저장(Storge)" 등의 국가적 연구개발 프로젝트를 2007년 3월로 종료했다. 또한 2006년도부터 신규로 "저손실 옵티컬(Optical) 신기능 부재"의 연구개발을 시작했으며, 이어서 이미 지난 2002년에 완료된 "나도메타제어 광디스크시스템" 연구개발 프로젝트의 성과와 관련하여 실용화를 향한 활동을 진행하고 있다. 또한 종래부터 검토.제안해온 PDP(플라즈마 디스플레이)의 기술개발에 대해서도 지원.협력을 진행하고 있으며, 차세대 디스플레이의 기반기술에 관한 조사를 실시하여 보고서를 정리했다. 본 고는 앞선 기술개발을 추진하고 있는 일본의 사례를 통해 광기술 흐름을 살펴보고 국내업체들의 광기술 개발에 도움이 되고자 ‘일본 재단법인 광산업기술진흥협회의 2006년도 사업보고서’ 주에서 발췌.정리한 것이다. 번역은 (주)그린광학의 유정훈 과장이 수고해 주셨다.

• Journal of the Korea Safety Management & Science
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• v.16 no.4
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• pp.185-191
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• 2014

In this study safety distance was investigated for small-scale LNG storage facilities in order to provide basic data for safety. The results are as follows; (1) For explosion pressure criteria, current criteria are reasonable, but water spray system should be recommended to LNG storage tank to ensure safety. (2) For criteria based on the results of the quantitative risk assessment, criteria applied to people are $5kW/m^2$ for radiation, LFL for dispersion, and 7kPa for explosion pressure. And criteria applied to facility are $37.5kW/m^2$ for radiation and 20 kPa for explosion pressure.

• Journal of the Korea Safety Management & Science
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• v.18 no.3
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• pp.71-80
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• 2016

This study is on safety improvement measures through analysis of accident cases during plant storage tank construction. Storage tank is a general term for artificial ground facility constructed to store oil, water, gas, and other chemicals. Some companies have clustered storage tanks (tank farm). The construction methods vary according to the component and types of fluids. Because most of the construction procedures include lifting heavy weight materials using heavy construction equipment and are carried out at high places, storage tank construction contains more risk factors than normal aerial construction. Recently, major accidents such as storage tank collapse have occurred often, and cost many lives due to the characteristics of the structure. In this study we would like to analyze the cause of these accidents and propose measures to improve safety.