• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.819-826
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• 2011

The proton exchange membrane fuel cell (PEMFC) is regarded as the most promising alternative power sources for unmanned aerial vehicle (UAV) due to its high energy density and silent operation. Since there are many load changes during UAV flight, thermal management is one of the important factor for the performance of PEMFC. In order to reduce the UAV weight for the stable operation of UAV, thermal management system (TMS) studied in this work does not use the fan but use the air flowing into UAV by UAV flight. In order to develop the passive type heat exchanger (HEX) for 1kW PEMFC, four types of HEXs are fabricated and their cooling performances are compared. The parametric study on the cooling performance of HEXs has performed with the variation of operating parameters such as mass flow rates and inlet temperature of air and coolant. Type 4 has the best performance in every case. This study can be helpful to achieve the optimal design of HEX for PEMFC powered UAV.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.21-28
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• 2013

The paper proposes an optimal sizing method of a customer's battery energy storage system (BESS) which aims at managing the electricity demand of the customer to minimize electricity cost under the time of use(TOU) pricing. Peak load limit of the customer and charging and discharging schedules of the BESS are optimized on annual basis to minimize annual electricity cost, which consists of peak load related basic cost and actual usage cost. The optimal scheduling is used to assess the maximum cost savings for all sets of candidate capacities of BESS. An optimal size of BESS is determined from the cost saving curves via capacity of BESS. Case study uses real data from an apartment-type factory customer and shows how the proposed method can be employed to optimally design the size of BESS for customer demand management.

• Nuclear Engineering and Technology
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• v.41 no.7
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• pp.921-928
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• 2009

As part of an evaluation for an in-vessel severe accident management strategy, a coolant injection into the reactor vessel under depressurization of the reactor coolant system (RCS) has been evaluated in detail using the SCDAP/RELAP5 computer code. A high-pressure sequence of a small break loss of coolant accident (SBLOCA) has been analyzed in the Optimized Power Reactor (OPR) 1000. The SCDAP/RELAP5 results have shown that safety injection timing and capacity with RCS depressurization timing and capacity are very effective on the reactor vessel failure during a severe accident. Only one train operation of the high pressure safety injection (HPSI) for 30,000 seconds with RCS depressurization prevents failure of the reactor vessel. In this case, the operation of only the low pressure safety injection (LPSI) without a HPSI does not prevent failure of the reactor vessel.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.211-218
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• 2012

In this paper, we propose a system architecture of the AMI to be applied in the modern agricultural sector. Agricultural electricity costs in South Korea is very inexpensive compared with other industries. It is expected to increase oil prices to rise over the medium to long term so the facilities must to be installed for farmers in terms of energy savings and energy costs. The research and development of plant factory which can replace the ills of modern agriculture is very active. The technologies of smart grid and plat factory are good paradigm of next generation agricultural sector. Good use of smart grid technologies, the traditional energy consumption industries, agriculture sector can be self-sufficiency industry. In this article the AMI architecture is developed and it will be applicable for modern farmers plant factory.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.2
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• pp.231-238
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• 2011

A role of Distribution Automation System(DAS) is required to be changed from observing and control to complex and various new system including functions which monitoring, control, prediction, operation and management of EMS type according to be gradually Smart Grid of distribution operation system for development of further power system industrial. IEC(International Electrotechnical Commission) published communication standards which interface and data model of distribution operation system to IEC 61968 and of host system like EMS(Energy Management System) to IEC 61970. So far, each standards are emphasizing themselves, but if they are applied by designed integration of the standards, it could be more efficiency system. So, in this paper, integration application of IEC standards and structure of further distribution operation system to use them are proposed by gradually increasing importance of communication protocols, functions and roles in further distribution management system considering Smart Grid.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.305-310
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• 2012

In 2009, The Ministry of Land, Transport and Maritime Affairs, Korea opens apartment maintenance fee to public in "Apartment Management Info System". The high energy consumption component of apartment, which is hot water, water, electricity and heating, is released to public on this system. Through this system, apartment energy consumption and greenhouse gas emissions data can be compiled and expected to be accurately analyzed. Energy consumption and greenhouse gas emissions statistics of the apartment are collected being made to reduce energy and gas emissions. However, The accurate survey of energy consumption trends have not been accomplished. The energy consumption and greenhouse gas emissions survey in Apartment should be made first in order to reduce energy consumption. and then the correlation factors analysis which is affecting energy consumption is required. The purpose of this study is to analyze energy consumption characteristics of apartment in Bundann-gu, Seongnam, Korea in monthly, unit area and building built year basis. And then the research can be used as the basis of policy to Reduce energy consumption and greenhouse gas emissions.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.17 no.4
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• pp.1-14
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• 2021

Recently, various renewable systems have been developed and applied in Korea. However, there are many systems which were not utilized in real buildings or not widely spread in the market. Furthermore, the attention of most users focused on several certain system such as PV or solar system. Therefore, this research aims to find user's needs for renewable energy based on perception surveys to improve the acceptance of technology in line with the world's energy flow. The survey was conducted by classifying respondents by various criteria, and the results were analyzed using AHP technique and CVM technique, focusing on preference and acceptance. According to the results of the survey, it was found that the people felt the need for renewable energy but lacked knowledge about renewable energy compared to the various government-implemented renewable energy supply policies. Therefore, a government-level policy is needed so that the people can have universal knowledge about renewable energy system.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.285-288
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• 2009

정부는 최근 그린홈 100만호 사업을 중심으로 각종 신재생에너지 보급률 향상을 도모하는 많은 프로그램을 기획하여 현재 약 12개의 신재생 에너지 보급지원 프로그램과 R&D 프로그램을 운영하고 있다. 그러나 현재 국내 신재생에너지 정책 및 프로그램은 차후 개선 및 체계적인 운영을 위한 조직적인 프로그램 평가 체계를 갖추고 있지 않으며 평가 기관이나 평가 주기 등 평가에 필요한 기본적인 합의와 법제적 배경 역시 미비한 상황으로 신재생에너지 프로그램의 평가 제반 시스템에 대한 근본적 고민이 필요한 시점이라고 볼 수 있다. 이에 본 연구에서는 미국 DOE(Department of Energy)산하 EERE(Energy Efficiency & Renewable Energy)의 신재생에너지 보급사업평가체계를 분석하여 EERE 프로그램 평가 방법의 국내 적용 가능성을 검토해 보았다. EERE는 미국의 에너지 효율화 및 신재생에너지 전담 사무국으로 10개의 에너지효율화 및 신재생에너지 연방정부 프로그램을 운영하고 있으며 Strategic Management system을 통해 효율적인 프로그램 관리를 시도하고 있다. 특히 General program evaluation Guideline에서는 표준화된 세부 평가 방법론을 제시하여 정례적 혹은 일회적 평가를 시행하고 있는데 이 세부 평가 방법들은 프로그램의 특성에 따라 프로그램을 운영하고 프로그램의 존속 및 개선여부를 결정하는데 결정적인 도움을 주고 있어 차후 국내에서 시행되고 있는 신재생에너지 프로그램의 정성적/정량적인 평가를 시행하는 많은 시사점을 제공할 것으로 기대된다.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.106-111
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• 2014

In order to manage the gradual increase of electricity demand, the United States, Japan, and Europe are seeking to achieve overall change of electric power system by introducing solutions such as smart grid. Among these solutions, there are various research projects regarding the Electricity Storage System (ESS), which aims to promote the efficient usage of electricity and grid system of new and renewable energy system. Korean government revised the law by including ESS in new and renewable energy facilities to accelerate ESS deployment. Following the same direction of the government policy, this study suggests methodologies of setting REC weighted value that guarantees investment financial feasibility when new and renewable power producers install ESS.

• Journal of Energy Engineering
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• v.27 no.2
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• pp.32-48
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• 2018

Monitoring of energy use should be a priority in order to efficiently manage building energy use. Energy use in buildings can be managed by dividing them into energy sources, uses, and ZONE. By energy source, electricity, gas, fuel, and district heating are supplied to run the building's facilities. The purpose can be divided into five main applications, including cooling, heating, lighting, hot water and ventilation, but not many elevators and electric heaters that are difficult to include in the five applications are classified. ZONE Star refers to the comparison or separate management of areas for which the purpose of the building is similar or different. In addition, energy efficiency management requires control of the temperature, humidity, and people who will be measuring energy in the building, and the recent problem of fine dust should directly affect the ventilation of the building.