• 전기의세계
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• v.45 no.1
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• pp.7-9
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• 1996

분산형전원 (Dispersed Storage and Generation System)이란 원자력이나 대용량 화력 등과 같은 집중적이고 대용량이 아닌 소용량의 전력저장시스템이나 발전시스템을 일컫는 말로서 소수력, 태양광, 바이오, 풍력 등의 대체에너지 전원, 소용량의 열병합발전시스템, 전기 등을 이용한 전력 저장시스템이 그 예라 하겠다. 이러한 분산형전원은 그 단어 뜻대로 대규모 전력계통에 비하여 분산되어 있기 때문에 관리가 어렵고 전력계통에 연계될 경우 여러가지 문제를 야기시키게 된다. 이러한 문제중 가장 큰 것은 계통의 전압변동의 요인이 되는 것이고 보호협조 문제 또한 무시할 수 없는 것이다. 더우기 보안상 단독운전이 될 경우를 방지하여야 하고 고조파문제, 계통단락용량 증대문제 등도 염려가 되는 문제이다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.85-91
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• 2014

Nowadays, Dynamic lighting control and management skills are studied and used. If the system which is to manage multiple intelligent spot applied ubiquitous service technology is built with decision making and used in the complex intelligent space like a apartment then will improve energy efficiency and provide comfortability in optimal conditions. To solve this problem distributed autonomous control middleware and energy management system which process data gathering by zigbee mesh network and search proper services to save energy by the existing state of things is necessary. In paper we designed DDLEMS (Distributed Dynamic Lighting Energy Management System) that is to service duplex communication embedded by software based home server platform to provide mobile services in the smart place and support decision making about energy saving to the best use of wireless censor node and controled network, energy display devices.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.10
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• pp.1873-1880
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• 2016

Most of the energy used to operate a cellular network is consumed by a base station (BS), and reducing the transmission power of a BS is required for energy-efficient cellular networks. In this paper, a distributed transmit power control (TPC) algorithm is proposed based on the flocking model to improve the energy efficiency of a cellular network. Just as each bird in a flock attempts to match its velocity with the average velocity of adjacent birds, in the proposed algorithm each mobile station (MS) in a cell matches its rate with the average rate of the co-channel MSs in adjacent cells by controlling the transmit power of its serving BS. Simulation results show that the proposed TPC algorithm follows the same convergence properties as the flocking model and also effectively reduces the power consumption at the BSs while maintaining a low outage probability as the inter-cell interference increases. Consequently, it significantly improves the energy efficiency of a cellular network.

• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.103-105
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• 2007

최근에 와서 유가상승, 화석에너지의 고갈문제, 환경 문제로 인해 분산전원에 대한 관심이 높아지는 추세에 있다. 소형 원자력을 동력으로 하는 전력시스템은 열병합발전과 같이 전기와 열을 동시에 생산하며, 분산전원 및 도서지역의 지역 에너지시스템으로 적용 가능한 다목적 에너지시스템이다. 본 논문은 소동력로가 울릉도 계통에 미치는 영향을 모의하였고, 모의를 위해 PSS와 RTDS를 사용하였다. 또한 울릉도 내의 디젤반전기와 소동력로의 전기적 특성을 비교 검토하여, 지역 에너지시스템의 유용성을 확인하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.523-524
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• 2015

신재생 에너지는 발전 시 연료가 들지 않는다는 특징과 친환경적인 이유로 각광 받고 있다. 이러한 특징으로 인해 에너지 독립 계통을 구성하는 데 주요 역할을 한다. 풍력, 태양광, 에너지 저장 장치 등이 분산 전원으로서 계통을 구성하게 되는데, 낮은 효율과 높은 초기 설치비용으로 인해 디젤 발전기나 마이크로 터빈 등 소형 발전기를 예비 전력으로서 부착하는 경우가 대부분이다. 이러한 분산 전원들은 가격이 제각각이며 기존의 화석연료 발전기처럼 비용 함수 모델링이 어려워 경제적 분석이 어려웠다. 이 논문은 이러한 신재생 에너지를 사용한 독립 마이크로그리드를 경제적 관점에서 분석하는 것이 목적이다. 따라서 계통을 분석하는 가장 보편적인 방법인 최적 조류 계산(OPF, Optimal Power Flow)방법과 가격을 최소화하는 점을 찾는 경제급전(ED, Economic Dispatch)방법을 사용하였다. 두 가지 방법의 결과를 비교하여 발전 비용을 줄일 수 있는지에 대해 조사하였다. 7-Bus 가상 계통을 만들어 사용하였고, OPF와 ED의 발전 비용은 PowerFactory$^{(R)}$ 프로그램을 통해 시뮬레이션 하여 데이터를 얻었다.

• Proceedings of the KSEEG Conference
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• 1999.04a
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• pp.273-275
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• 1999

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.227-231
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• 2008

The purpose of this study is to clarify the behavior of stranded crude oil and to estimate the restoration of seawater infiltration by application of dispersant as one of cleaning techniques. We made visualization of infiltration process of seawater and stranded crude oil on the sandy beach sediments by using of a model sandy beach. Major conclusions derived from this study are as follows. The seawater infiltration volume was reduced by the stranded crude oil. However, thirty percentage of the sweater infiltration into the sediments was restored by dispersant application to the penetrated oil in sandy beach. The penetration depth of stranded oil were dropped at first falling tide, but were not significantly fluctuated after that. Moreover, oil concentration was most high within the upper 2 cm. The stranded crude oil was broken into small size droplets and dispersed into the sediments by the dispersant application. Therefore, dispersant applications play an important roles in the large increase of surface area of given volume of oil, and it resulted in promoting to biological degradation process at the oil/water interface, dispersing the stranded oil into the water column and restoration of the supplement of the dissolved oxygen and nutrients to the benthic organisms.

• JOURNAL OF ELECTRICAL WORLD
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• s.313
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• pp.72-74
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• 2003

• Environmental engineer
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• s.325
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• pp.10-13
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• 2013

• Journal of the Economic Geographical Society of Korea
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• v.16 no.4
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• pp.647-669
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• 2013

Depletion of fossil fuels and sharp rise of international oil price as well as climate worming and frequent environmental disasters have required to strengthen resource(esp. energy) and environmental policy and discourse. And hence highly influential discourses and policies such as the concept of sustainable development and strategy for carbon regulation have been developed and pursued world-widely. But these concept and strategy have seemed to be subsumed in the process of neoliberalism, so as to have little effective results. This leads us to energy transition and energy autonomy or autarky as alternative strategic and normative concepts. Daegu has shown strong interests in urban energy problems relatively earlier than other cities, and developed the so-call 'Solar City' project. But it could not properly tackled with the problems, while tending to meet with the global imperatives. This paper considers urban energy problems and energy policy of Daegu with its significance and limitations, and suggests 4 principles for urban energy transition and autonomy with some concrete alternative measures; that is, the transition from fossil and nuclear energy to renewable energy, the transition from supply-led policy to demand side focusing policy, the transition from central governing energy system to locally distributed one, and the transition from market-dependent management to citizen-participatory energy governance.