• 한국해양환경ㆍ에너지학회지
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• 제2권2호
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• pp.31-37
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• 1999

본 논문에서 저자들은 선박의 자동 인식 시스템(AIS: Automatic Identification System)을 이용한 광역 해상 교통 관제 시스템의 개념과 현재의 추세를 소개하면서 동시에 초기 개발을 시도하였다. 이를 위해서 무궁화 위성을 AIS 개발을 위하여 사용하였다. 즉 해상에서 GPS에 의해 얻어지는 선박의 위치가 무궁화 위성을 통하여 관제 센터에 인력의 개입 없이 자동으로 보고되는 시스템을 구축하였다. 이와 같은 시스템은 레이더를 이용하는 기존의 관제 시스템보다 더욱 넓은 영역을 통제할 수 있으며 정보의 불확실성도 매우 감소한다. 본 연구에서 개발된 시스템의 시험 관제 결과는 인공위성과 AIS를 이용한 광역 해상 교통 관제 시스템의 충분한 가능성을 보여주고 있다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1089-1095
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• 2014

Innumerable microgrids would be operated independently by individual operators in a future smart grid. This kind of decentralized power system requires entirely different operation scheme in the actual power system and electricity market operation. Especially, frequency regulation is very important for successive energy trade in this multi-microgrid circumstance. This paper presents an optimal energy and reserve market participation strategy and operation strategy of energy storage system (ESS) by a microgrid operator (MGO). For definite evaluation of the proposed strategy, we postulate that the MGO should participate in the Power Exchange for Frequency Control (PXFC) market, which was devised by Maria Ilic and her coworkers and is suitable to the decentralized operation circumstances. In particular, optimal reserve capacity of the frequency control market and optimal market participation ratio of ESS between frequency control market and energy market are derived theoretically and evaluated by simulations utilizing Nordic Pool Elspot price data.

• 자원ㆍ환경경제연구
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• 제33권2호
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• pp.113-133
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• 2024

태양광과 풍력을 중심으로 한 변동성 재생발전(VRE)은 탄소중립 달성의 주요수단이지만 높은 변동성과 불확실성으로 인해 전력공급의 안정성을 훼손시킨다. 에너지저장장치(ESS)는 수요이전을 통해 재생발전의 출력제한을 경감시킬 뿐만아니라 보조서비스 제공을 통해 안정적인 전력시스템 운영에 기여할 수 있다. 본 연구는 VRE로 인한 문제점이 점점 본격화되는 상황에서 ESS자원을 수요이전 기능과 예비력 제공기능 간에 어떻게 분배하는 것이 전력공급 효율성 최대화에 기여할 수 있는지 분석한다. 분석모형으로 재생발전의 변동성과 불확실성을 현실적으로 모의할 수 있는 확률적 전력시스템 최적화 모형을 적용하였다. 분석시점은 2023년과 2036년으로 설정하여 재생발전 보급수준별 ESS 최적자원분배 전략과 편익을 분석하였다. 분석결과는 크게 다음의 3가지로 요약가능하다. 첫째, ESS는 수요이전과 예비력 제공 모두에 탁월한 기능을 제공하며, 예비력 가격이 높게 설정될수록 수요이전 기능은 제한하고 예비력 제공에 집중함을 확인할 수 있었다. 둘째, 재생발전 출력제한은 필요예비력에 대한 대체재 역할을 하며, 예비력 가격 수준이 높아질수록 출력제한은 증가하고 필요예비력은 감소하는 것이 비용 합리적이다. 셋째, 기회비용이 반영된 합리적인 예비력 가격이 적용될 경우 ESS는 가까운 미래에 경제성을 확보할 수 있으며, ESS의 경제성은 재생발전 비중이 높을수록 더 커짐을 확인할 수 있었다. 본 연구는 전력공급 자원이 효율적으로 분배될 수 있는 가격기능이 바로 설때 비용 효율적인 전력부문 저탄소 전환이 가능함을 시사한다.

• 한국농공학회논문집
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• 제49권6호
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• pp.55-62
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• 2007

Actual states of energy utilizations were investigated and analyzed on three representative rural villages in Chungcheongnam-Do. Rural residents were almost using the ondol boiler as a heating facility and oil(diesel, kerosene) and electricity(night thermal-storage power service) as a heating energy. There were a few households using briquette or firewood in a fuel hole with Korean hypocaust. Most of their cooking facilities were gas ranges using LPG. The most popular hot-water supply system was an oil boiler and the next was an electricity boiler. The amount of energy use in a rural household generally showed 20,000 to 40,000 won/month of the electric power rate, 400 to 800 liter/year of the oil and 60 to 120 kg/year of the LPG. Prompt measures should be taken to promote the spread of new and renewable energy such as solar heat, biomass and wind power, etc.

• 전기학회논문지
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• 제65권4호
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• pp.555-560
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• 2016

Recently, many countries have placed great attention on energy security and climate changes. Governments are promoting the construction of renewable energy projects with regulatory support in Korea. Despite an increasing penetration of renewable resources, however, the photovoltaic and wind power are underutilized due to the endemic problems such as difficulties of output control and intermittent output. The Energy Storage System (ESS) is proposed as a good solution for solving the problems and has been studied in both the private business and the government. However, because of inefficient aspects, the research has been carried out for improving high costs and a small capacity. In addition, the ESS is currently installed for using only one purpose which is frequency regulation or transmission congestion relief such that has an economic limitation. Therefore, methods which are becoming economically justifiable to increase the penetration of the ESS is required. Thus, this paper presents in terms of operation efficiency to improve economic feasibility of the ESS currently used. mainly, there are two aspects for the operation efficiency. Firstly, it is intended to improve the utilization rate through a process that can utilize the ESS for various purposes. It is necessary to be able to use for other purposes by classifying and clustering for increasing the efficiency of availability. The clustering method is proposed to conduct the grouping the ESS. Especially, it is proposed to utilize ESS for frequency regulation service which is the one of ancillary services in the power system. Through case studies, it is confirmed to secure the necessary resources by clustering small size ESS.

• Journal of Information Processing Systems
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• 제16권3호
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• pp.648-662
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• 2020

Bluetooth low energy (BLE) beacon is an actively push-to-broadcast electronic signal and can be used for object identification. This paper uses such beacon-based identification and Internet of Things (IoT) technologies for the elder health management service system to simplify the user interfaces and steps for preventive elder care. In the proposed system, an elder's family member, caregiver, or medical worker can conveniently and quickly record daily health management information. Besides, through the statistics and analysis of the data on the back end of the system, it is helpful for the elderly to refer to the data of daily care management and future management trends. Similarly, it is also an essential reference data for system maintenance and the new preventive health care services development.

• 신재생에너지
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• 제16권1호
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• pp.25-30
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• 2020

In this study, an SW for the analysis of the wind-turbine vibration characteristics was developed as an application of SaaS cloud infrastructure. A measurement system for power-performance, mechanical load, and gearbox vibration as type-test class was installed at a target MW-class wind turbine, and structural meta and raw data were then acquired into the cloud. Data processing algorithms were developed to provide cloud data to the SW. To operate the SW continuously, raw data was downloaded consistently based on the algorithms. During the SW test, an intermittent long time-delay occurred due to the communication load associated with frequent access to the cloud. To solve this, a compression service for the target raw data was developed in the cloud and more stable data processing was confirmed. Using the compression service, stable big data processing of wind turbines, including gearbox vibration analysis, is expected.

• 한국시뮬레이션학회논문지
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• 제17권4호
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• pp.123-131
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• 2008

무선 센서 네트워크 시스템에서 에너지 효율을 증가시키기 위한 연구가 활발하게 이루어지고 있으며 그중에서도 통신과 관련된 에너지 소모를 감소시키는 연구가 가장 많이 진행되어 왔다. 실제로 각 노드에서는 통신 및 센싱이 빈번하게 일어난다. 그러므로 통신에서의 에너지 효율을 증가시키기 위해서는 센싱 주기와 전송 주기를 제어하는 기능이 요구된다. 또한 질의에 해당하는 노드에게만 질의를 전파함으로써 전송횟수의 감소를 통하여 에너지 소비를 감소할 수 있다. 본 논문에서는 질의어를 통해 센싱 주기와 전송 주기를 제어할 수 있는 노드 관리 기능과 서비스 디스커버리 기술을 응용하여 질의에 해당하는 노드에게만 질의 전파 제한 메커니즘을 제안하고, 구현하며 성능을 평가한다.

• 조명전기설비학회논문지
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• 제27권5호
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• pp.95-103
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• 2013

Protection of the electrical and electronic equipment against surges in low voltage AC power distribution systems is based on wide applications of surge protective devices(SPDs). Cascade application of SPDs located at the service entrance of a building and near sensitive equipment is intended to ensure the optimal voltage protection level and energy sharing among cascade SPDs. In this paper, when surges impinge at the service entrance of the building of interest, the protection characteristics of two-stage cascade SPD systems were investigated. The influence of the distance between the upstream and downstream SPDs on the voltage protection level and energy sharing of the two-stage cascade SPD systems were analyzed experimentally. It was found that the energy sharing of two-stage cascade SPD systems strongly depends on the distance between the two SPDs and the component of SPD. As the distance between the two SPDs increases, the energy absorbed by the upstream SPD increases while the energy absorbed by the downstream SPD decreases. Consequently, it is desirable to select the upstream and downstream SPDs having the proper energy capability with due consideration of the distance between the two SPDs.

• 대한임베디드공학회논문지
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• 제7권2호
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• pp.103-111
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• 2012

This paper introduces a novel concept of 'A Green LED Sensitivity Lighting System' which can automatically estimate QoS(quality of service) and emotional requirements of user using smart phone. And it can intelligently control ambient illumination lamp to conserve electric energy and to satisfy human sensitivity. The proposed system has 4 control modes; emotional lighting, smart lighting, green lighting and realistic lighting modes in order to comfort man's emotion, to maximize work efficiency, to save energy consumption and to make the entertainment more fun, respectively. When we choose green lighting mode for indoor office situations, an elaborate simulation shows that the proposed system with home network can reduce the energy by 50% compared to conventional light control system with a fixed time-based switching.