• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.1035-1040
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• 2005

This paper deals with the design rule and performance results of the surge protective devices (SPDs) for low-voltage mains on shipboard. The proposed SPDs consists of a metal oxide varistors (MOV) and a L-C filter to improve noise-elimination performance. Three kinds of SPDs are fabricated and tested by using a combination surge generator which produce the standard impulse current of 8/20${\mu}s$ 2.1kA. As a results, the proposed SPDs with series L-C filter have more excellent transient blocking and noise reduction performance than the conventional ones.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1464-1465
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• 2007

The purpose of this paper is to identify the requirements for Surge Protective Devices (SPDs) used in protecting telecommunication and signalling system. All of these systems may be exposed to the effects of lightning and power line faults, either through direct contact or induction. These effects may subject the system to overvoltages or overcurrents or both, whose levels are sufficiently high to harm the system. SPDs are intended to provide protection against overvoltages and overcurrents caused by lightning and power line faults. This paper describes tests and requirements which establish methods for testing SPDs and determining their performance.

• 조명전기설비학회논문지
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• 제27권3호
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• pp.100-106
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• 2013

In this paper, in order to analyze lightning impulse response characteristics in combined installations of SPDs and RCDs, surge protection coordination between SPDs and RCDs are experimentally investigated by using the combination wave generator. Six different types of single-phase residual current operated circuit-breakers with integral overcurrent protection for household and similar uses(RCBOs) being present on the domestic market are tested according to KS C IEC 61009-1 standard. As a result, when a class I SPD is located on the source side of an RCBO, all kinds of specimens are able to provide the proper coordination between the SPD and RCBOs without nuisance tripping, unintended operation or damage due to test impulse currents. However, in the case that the class II SPD is located on the load side of RCBOs, a lot of L-N mode injected currents is split into the RCBO, and a few RCBOs are damaged. Coordination between SPDs and RCDs is not valid and a role of SPDs is of no use. When combining SPDs with RCDs, it is necessary to select SPDs and RCDs in consideration of the protection voltage level of metal oxide varistor embedded in RCDs.

• 조명전기설비학회논문지
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• 제29권4호
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• pp.116-125
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• 2015

This paper presents experimental results obtained from actual installation conditions of surge protective devices (SPDs), with the aim of understanding the coordination of cascaded Class I and Class II SPDs. This paper also proposes effective methods for selecting and installing coordinating cascaded SPDs. The residual voltage of each SPD and the energy sharing of an upstream Class I tested SPD and a downstream Class II tested SPD were measured using a $10/350{\mu}s$ current wave. In coordinating a cascaded voltage-limiting SPD system, it was found that energy coordination can be achieved as long as the downstream SPD is a metal oxide varistor with a higher maximum continuous operating voltage than the upstream SPD; however, it is not the optimal condition for the voltage protection level. If the varistor voltage of the downstream SPD is equal to or lower than that of the upstream SPD, the precise voltage protection level is obtained. However, this may cause serious problems with regard to energy sharing. The coordination for energy sharing and voltage protection level is fairly achieved when the cascaded SPD system consists of two voltage-limiting SPDs separated by 3 m and with the same varistor voltage.

• 조명전기설비학회논문지
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• 제20권2호
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• pp.60-67
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• 2006

이 논문은 서지보호기의 설치조건에 따른 보호효과에 대하여 기술하였으며, 뇌서지로부터 정보통신설비를 효과적으로 보호하는 설치기법을 제안하기 위해 서지보호기의 보호효과에 미치는 설치위치, 분기회로의 길이, 배선방법, 전선관 재료의 영향에 대해서 실규모 조건에서의 실험을 수행하였다. 그 결과, 보호하고자 하는 각각의 전자기기의 입력단에 서지보호기를 설치하는 것이 효과적이며, 선간에 서지보호기를 설치할 때는 접속선의 길이가 최소가 되도록 하는 배선방법이 효과적이다.

• 조명전기설비학회논문지
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• 제21권1호
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• pp.35-41
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• 2007

최근 고품질의 정보통신서비스와 안정한 전력공급에 대한 사회적 요구가 증가하고 있다. 본 연구에서는 뇌서지로부터 정보통신설비를 효과적으로 보호하는 대책을 제안하기 위해서 실규모 실험회로를 적용하여 여러 가지 설치조건에 따른 서지보호기의 보호효과를 실험적으로 조사하였다. 그 결과 전원계통의 접지방식, 분기회로의 수, 접지선의 배선방법 등에 따라 서지보호기의 보호효과는 크게 다른 것으로 밝혀졌다. 정보화 기기용 서지보호기를 설치하는 경우, 전원선과 통신선을 포함하는 공통접지방식과 접지선을 전원선과 일괄하여 금속관 내에 배선하는 것이 서지보호기의 서지차단성능의 향상에 가장 효과적이었다.

• 대한산업공학회지
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• 제20권1호
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• pp.99-112
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• 1994

This paper describe the development of a systematic method of slicing solid parts based on a data structure called Sliced Profile Data Structure(SPDS). SPDS is an augmented polygon data structure that allows multiple layers of sliced profiles to be connected together. The method consists of five steps: (1) Selection of slicing directions, (2) Determination of slicing levels, (3) Creation of sliced profiles, (4) Connection of sliced profiles, and (5) Refinement. The presented method is aimed at enhancing the applicability of CSG for manufacturing by overcoming the problem of non-uniqueness and global nature. The SPDS-based method of feature extraction is suitable for recognizing broad scope of features with detailed information. The method is also suitable for identifying the global relationships among features and is capable of incorporating the context dependency of feature extraction.

• Nuclear Engineering and Technology
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• 제19권1호
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• pp.42-50
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• 1987

고리 2호기와 원자력 안전센터 상황실을 연결하는 Nuclear Data Link System에 대하여 기술하였다. 특히 선정된 원자력 안전변수, Data Link용 Pseudo-Network 소프트웨어, 관련장비들의 입출력 기능 및 전송된 자료의 영상화 등의 내용을 포함하였다. 아울러 현재까지 수행해온 고리 1,2,5,6호기에 대한 비상대응 설비의 설계 내용과 ERF/SPDS 하드웨어 및 소프트웨어 국산화 연구 방향을 제시하였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.1161-1165
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• 2005

Due to the miniaturization of electrical components and assembles on signal circuits, transient overvoltages caused by switching operation or lightning surges have become more interesting concern to the field of electrical engineering. In this paper, the development of surge protective devices(SPDs) that can protect sensitive signal device on shipboard from overvoltages are described. Two kinds of SPDs are designed and tested by using a combination surge generator which can produce the standard impulse current of 8/20${\mu}s$ 2.1kA according to the IEC 61000-4-5 standard. From the simulation and experimental results, it is confirmed that the proposed SPDs have an enough protection performance with a low insertion loss and a low clamping voltage.

• 약학회지
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• 제52권2호
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• pp.160-164
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• 2008

This study investigated the current status and drug expenditure of the drug shortage prevention program in Korea. National health insurance claims data from 2001 to 2005 were analyzed for the drugs with inadequate supply, which were designated as shortage prevention drugs (SPDs). Drug use of SPDs have increased every year, but the average increase rate of drug expenditure for SPDs, 13.5% was lower than that for all the reimbursed drugs, 18.6%. Drugs with price increase based on production cost were more actively used than drugs with prescription incentives for doctors.