• 한국가스학회:학술대회논문집
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• 한국가스학회 2006년도 추계학술발표회 논문집
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• pp.191-195
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• 2006

전력선에 지락고장이 발생할 경우 대지로 유입된 고장전류에 의하여 인접한 배관에 아크 용융이 발생하면 가스폭발이나 기름유출과 같은 대형사고를 발생시킬 수 있으며, 배관의 유지 및 보수를 담당하는 작업자의 안전에도 위험을 초래할 수 있다. 본 논문에서는 대지를 통한 철탑과 배관 사이의 아크 발생에 대하여 알아보고, 국내외에서 사용되고 있는 철탑 인근에 매설된 배관의 이격거리 기준을 조사하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.184-186
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• 2005

Increasement of power demand rapid industrial growth has led the expansion of power system, and it caused construction of large power transmission line(like 765kV T/L) and substation. If there are T/L faults (route contingency etc), it lead to the large scale black out in SEOUL AREA (the center of load). To minimize damage which caused by the large scale black out, KEPCO selects the method of load shadding. In this work, instead of general method of load shadding, We study the application of UVLS model to decrease the load shadding in SEOUL AREA. The study result of using the UVLS model showed that the amont of load shadding can be decreased about 400 MW compare to the existing load shadding system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기설비전문위원
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• pp.53-55
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• 2005

Because of the continuous growth of energy consumption and also the tendency to site power lines and pipelines along the same route, the close proximity of power lines and buried metallic pipelines has become more and more frequent. The lightning strokes collected by an electric substation or power line tower might cause arcing through the soil to an adjacent gas pipeline. This paper gives the review of the breakdown mechanism and the standards of separation distance between lower and pipelines.

• 디지털융복합연구
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• 제13권7호
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• pp.207-212
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• 2015

사물 인터넷을 구성하는 센서 네트워크는 주변 환경의 여러 정보들을 효율적으로 수집하여 앵커 노드로 보내기 위해서 최적의 경로를 선택하여 센서 간의 통신비용 및 수명 연장을 위해 많은 연구가 필요하다. 센서 네트워크에서 센서노드는 저전력, 저용량을 갖는 확장 장치이다. 이들 노드들 간의 데이터 전송을 위한 라우팅 방법을 위해 인접한 지역에 있는 앵커와 노드간의 연결은 적은 오류로 비교적 정확해야 한다. 이러한 지역화를 위한 기존의 방법 중 CA(Centroid Algorithm)는 자주 사용하는 방법이기는 하지만 오류가 자주 일어난다. 본 논문에서는 이러한 오류 발생의 문제점을 최소화하기 위해 Radical Line을 기반으로 한 센서 노드 간에 range-free 지역화 방법을 제안한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권6호
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• pp.253-259
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• 2002

This paper deals with the effects of grounding conductors for metal oxide surge arresters. When surge arresters are improperly installed, the results can cause costly damage of electrical equipments. In particular, the route of surge arrester connection is very important because bends and links of leads increase the impedances to lightning surges and tend to nullify the effectiveness of a grounding conductor. Therefore, there is a need to know how effective installation of lightning surge arresters is made in order to control voltage and to absorb energy at high lightning currents. The effectiveness of a grounding conductor and 18 [㎸] metal oxide distribution line arresters was experimentally investigated under the lightning and oscillatory impulse voltages. Thus, the results are as follows; (1) The induced voltage of a grounding conductor is drastically not affected by length of a connecting line, but it is very sensitive to types of grounding conductor. (2) The coaxial cable having a low characteristic impedance is suitable as a grounding conductor. (3) It is also clear from these results that bonding the metal raceway enclosing the grounding conductor to the grounding electrode is very effective because of skin effect. (4) The induced voltages of grounding conductors for the oscillatory impulse voltages are approximately twice as large as those for the lightning impulse voltages.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1073-1080
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• 1999

Optimal routing of distribution networks can be attained by keeping the line power capacity limit to handle load requirements, acceptable voltage at customer loads, and the reliability indices such as SAIFI, SAIDI, CAIDI, and ASAI limits. This method is composed of optimal loss reduction and optimal reliability cost reduction. The former is solved relating to the conductor resistance of all alternative routes, and the latter is solved relating to the failure rate and duration of each alternative route. The routing considering optimal loss only and both optimal loss and optimal reliability cost are compared in this paper. The case studies with 10 and 24 bus distribution networks showed that reliability cost should be considered as well as loss reduction to achieve the optimal routing in the distribution networks.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.915-917
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• 1998

Optimal routing of distribution networks can be attained by keeping the line power capacity limit to handle load requirements, acceptable voltage at customer loads, and the reliability indices such as SAIFI, SAIDI, CAIDI, and ASAI limits. This method is composed of optimal loss reduction and optimal reliability cost reduction. The former is solved relating to the conductor resistance of all alternative routes, and the latter is solved relating to the failure rate and duration of each alternative route. The routing considering optimal loss only and both optimal loss and optimal reliability cost are compared in this paper. The results showed that reliability cost should be considered as well as loss reduction to achieve the optimal routing in the distribution networks.

• 대한교통학회지
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• 제28권5호
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• pp.55-64
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• 2010

지하역사 미세먼지의 효율적 저감방안 마련을 위하여 서울지하철 5호선 개화산역 대합실, 승강장, 본선터널 3곳의 미세먼지 농도를 동시간대에 30분 단위로 측정하고, 각 위치에서 측정한 미세먼지농도 변화패턴 사이의 상관관계 분석을 통하여 지하역사에서의 미세먼지 확산방향과 확산속도를 추정하였다. 지하역사의 미세먼지 농도는 본선터널이 가장 높고, 승강장, 대합실 순으로 낮아진다. 본선터널과 승강장, 대합실의 미세 먼지농도는 열차운행이 많은 혼잡시간대에는 증가하고 비 혼잡시간대에는 감소하는 패턴을 보인다. 위치에 따른 미세먼지농도의 상대적인 크기와 변화패턴에 대한 통계적 분석결과 본선터널의 높은 미세먼지농도가 승강장으로 확산되고, 승강장의 미세먼지 중 일부가 대합실로 확산되는 것으로 나타났다. 따라서 지하역사의 미세먼지를 효율적으로 감소시키기 위해서는 본선터널 내 미세먼지 집중발생지점과 발생원, 확산경로, 확산수단 등을 정확하게 파악하여 발생원을 제거하거나 발생량을 저감시키는 것이 중요하며, 환기시스템 가동을 위치별로 미세먼지농도가 높아지는 시간대에 맞추어 가동시킴으로써 전력사용량과 피크전력을 줄일 수 있다.

• Strategy21
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• 통권37호
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• pp.104-143
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• 2015

China's new grand strategy, the "One Belt, One Road Initiative" (also Belt Road Initiative, or BRI) has two primary components: Chinese President Xi Jinping announced the "Silk Road Economic Belt" in September 2013 during a visit to Kazakhstan, and the "21^st Century Maritime Silk Route Economic Belt" in a speech to the Indonesian parliament the following month. The BRI is intended to supply China with energy and new markets, and also to integrate the countries of Central Asia, the Association of Southeast Asia Nations (ASEAN), and the Indian Ocean Region - though not Northeast Asia - into the "Chinese Dream". The project will be supported by the Asian Infrastructure Investment Bank (AIIB), due to open in 2016 with 57 founding members from all around the world, and China has already promised US$ 50 billion in seed funding. China's vision includes networks of energy pipelines, railways, sea port facilities and logistics hubs; these will have obvious commercial benefits, but also huge geopolitical significance. China seems to have two distinct aims: externally, to restore its historical sphere of influence; and internally, to cope with income inequalities by creating middle-class jobs through enhanced trade and the broader development of its economy. In South Korea, opinion on the BRI is sharply polarized. Economic and industrial interests, including Korea Railroad Corporation (KORAIL), support South Korean involvement in the BRI and closer economic interactions with China. They see how the BRI fits nicely with President Park Geun-hye's Eurasia Initiative, and anticipate significant commercial benefits for South Korea from better connections to energy-rich Russia and the consumer markets of Europe and Central Asia. They welcome the prospect of reduced trade barriers between China and South Korea, and of improved transport infrastructure, and perceive the political risks as manageable. But some ardently pro-US pundits worry that the political risks of the BRI are too high. They cast doubt on the feasibility of implementing the BRI, and warn that although it has been portrayed primarily in economic terms, it actually reveals a crucial Chinese geopolitical strategy. They are fearful of China's growing regional dominance, and worried that the BRI is ultimately a means to supplant the prevailing US-led regional security structure and restore the Middle Kingdom order, with China as the only power that matters in the region. According to this view, once China has complete control of the regional logistics hubs and sea ports, this will severely limit the autonomy of China's neighbors, including South Korea, who will have to toe the Chinese line, both economically and politically, or risk their own peace and prosperity.

• 해양안보
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• 제6권1호
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• pp.1-35
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• 2023

본 연구는 중국해군이 진행 중인 공세적 서해 진출 전략을 목표, 방법, 수단 차원에서 분석하여 우리해군의 대응전략 발전방향을 제시하는 것을 목적으로 한다. 분석결과 중국해군의 공세적 서해 진출전략은 목표 차원에서 미-중 경쟁 간 해양권익 수호 및 해양강국을 달성하기 위한 대전략과 연계하여 진행 중 있으며, 방법 차원에서 평상시 '진입 일상화'와 '관할권 행사'를 통해 국제사회가 서해를 중국의 내해(內海)로 인식하는 기반을 조성하며, 유사시는 항모전단의 압도적 선제공격 능력을 바탕으로 우리나라의 해양교통로를 차단하여 단시간 내 서해 해양통제권 확보를 시도할 것이라 예측된다. 수단 차원에서 항모전단 건설 가속화 및 원거리 미사일 교전능력을 향상시키고 있다. 이에 대응하는 한국해군 대응전략 발전방향으로 첫째 한국형 인도-태평양 전략과 연계한 국가 해양안보전략 수립 및 발전, 둘째 서해 중간선 이동(以東) 해역에 대한 효과적이 경비작전 개념 발전, 셋째 생존성과 치명성 강화를 위한 전투 수행개념 발전 및 능력 구축을 제시한다.