• Journal of Power Electronics
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• v.15 no.6
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• pp.1446-1455
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• 2015

This paper illustrates resonant tank design considerations and the implementation of a LLC resonant converter with a wide battery voltage range based on the fundamental harmonic approximation (FHA) analysis. Unlike the conventional design at zero load, the parameter K (the ratio of the transformer magnetizing inductor L_m to the resonant inductor L_r) of the LLC converter in this paper is designed with two charging points, (V_{o_min}, I_{o_max1}) and (V_{o_max}, I_{o_max2}), according to the battery charging strategy. A 2.9kW prototype with an output voltage range of 36V to 72V dc is built to verify the design. It achieves a peak efficiency of 96%.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.82-97
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• 2005

RPS (Renewable Portfolio Standards) is a policy tool to disseminate renewable energies through market mechanism. RPS promotes renewable power generation by obligating electricity market participants to deliver the required amount of electricity from renewable energies. To promote and encourage renewable energies, Korean government is considering to introduce RPS to domestic market in the near future. The purpose of this paper is to analyze the definition and market mechanism of RPS and to review key considerations in its design. In conclusion, we recommend some prerequisite in its introduction to Korea.

• Current Photovoltaic Research
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• v.1 no.2
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• pp.126-139
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• 2013

New national certified license tests for the facility management of new and renewable energy is given from this year. There are three national certified licenses including craftsman, industrial engineer and engineer. The subjects for the craftsman are photovoltaic facility for written exam and practical business of photovoltaic facility for writing exam. The subjects for the industrial engineer are theory, construction, management and law of the photovoltaic system for written exam and practical business of photovoltaic system for writing exam. The subjects for the engineer add one more subject compared with the industrial engineer, such as design of photovoltaic system. The first tests were given in september 28 in this year. The tests will be given three in 2014.

• Korean Institute of Interior Design Journal
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• v.23 no.3
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• pp.153-163
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• 2014

The eco-friendly elements are important for new construction and renovation and redevelopment of the buildings. The green buildings are related with minimizing environmental pollution and how to live with nature throughout the entire process of demolishing and building. The purpose of this paper is to study on eco-friendly business buildings in the trend of mandatory green building certification system. The analysis of this paper is comparative studies on practices at eleven domestic eco-friendly business buildings through site survey on design framework of green buildings. The design framework of eleven this buildings is six kinds of skills on technical, renewable, ecological, cultural, healthy, social. The eleven this buildings in the new & renewable energy and IT technology of technical sector are satisfied with the framework. But, domestic most advanced eco-friendly business buildings are placed difference between almost the two times on the lower buildings at comparative evaluation. The three of this buildings are gratified rainwater harvesting and waste recycling systems for renewable and recycle. The buildings have an excellent aspects of technology and ecology. The benefits of this buildings are related with future compulsory zero energy house to take technical advantage of renewable energy. However, the buildings reflecting the regional culture types is insufficient. The buildings should be supplemented as follows. This buildings are need to have the social enhancement programs and design for convenient space of community residents, through health and comfort of on workplace. Moreover, this buildings have features of coexisting with human beings and nature friendly with the aim of realizing the sustainable development. The social enhancement programs through regional cultural aspects with ecology are related with individual and community livings in harmony, non-hierarchical communal lifes. The development of the cultural aspects provide for consensus about the local community and creating sustainable communities. Thus, The buildings are to have energy saving, pleasant and healthy living environment and interactive individual and community livings in harmony.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2103-2108
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• 2016

Energy saving is as important as developments of green energy and alternative energy. This paper describes design of hybrid type streetlight for railway station with renewable energy as photovoltaic, wind, secondary battery. In designing hybrid type streetlight for railway station, generation energy with renewable energy and reliability is strongly needed to meet the demand of railway station. In order to achieve the high performance of a streetlight, photovoltaic, wind and secondary battery system, PV tracker, monitoring and GUI system with logging function are designed. To verify of performance of hybrid type streetlight for railway station, we have demonstration test to get of generation energy and flow of energy and the results are present in this paper.

• Korean Journal of Chemical Engineering
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• v.36 no.1
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• pp.12-20
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• 2019

An energy storage system consisting of a battery and a power-to-methanol (PtM) unit was investigated to develop an energy storage system for renewable energy systems. A nonlinear programming model was established to optimize the energy storage system. The optimal installation capacities of the battery and power-to-methanol units were determined to minimize the cost of the energy system. The cost from a renewable energy system was assessed for four configurations, with or without energy storage units, of the battery and the power-to-methanol unit. The proposed model was applied to the modified electricity supply and demand based on published data. The results show that value-adding units, such as PtM, need be included to build a stable renewable energy system. This work will significantly contribute to the advancement of electricity supply and demand management and to the establishment of a nationwide policy for renewable energy storage.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.256-262
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• 2009

Purpose of this study is embody the environmental-friendly military facility model that applied renewable energy, passive design method and high efficiency equipment. In the introduction of this study, defined problem of existing military facility and classification of military facility are performed. Also, environmental friendly military facility is defined through classified by scale and building equipment method. In the renewable energy chapter, photovoltaic system and wind turbine system are considered And then, LED light, photovoltaic panel, motor, inverter are analyzed in the high efficiency equipment chapter.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.590-593
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• 2009

Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

• KIEAE Journal
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• v.12 no.1
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• pp.105-112
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• 2012

When a building is planned and designed, the design should be able to minimize the cost during the whole life cycle of the building. This study has begun to analyze LCC about the alternative design which is applicable to renewable energy facility construction. It is reviewed domestic and foreign papers about the trend of LCC technology and it is determined the analytical method to analyze the LCC of renewable energy. Regarding the review of alternatives, it is chosen the three alternatives which are able to designed combing the renewable energy facilities and it is performed the LCC analysis about each alternative. Alternative 1 is Photovoltaic + Solar Thermal + Photovoltaic /Wind Power, Alternative 2 is Geothermal + Photovoltaic, and Alternative 3 is Photovoltaic + Solar Thermal. The LCC analysis is present value method, its analytical period is 40 years and it is applied 3.2% of real discount rate. As a result, it is proved that Alternative 1 and Alternative 3 are not able to collectible the early investment cost during the analytical period and Alternative 2 is analyzed that its pay-back period of early investment cost is about 31 years. As the final outcome of this study on case analysis, it is more advantageous to use the combination of Geothermal and Photovoltaic energy than to use the other combination in LCC aspect.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.8
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• pp.556-561
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• 2011

In this study, the theoretical maximum power of a heat engine was investigated by sequential Carnot cycle model, for a low-grade heat source of about $100^{\circ}C$. In contrast to conventional approaches, the pattern search algorithm was employed to optimize the two design variables to maximize power. Variations of the maximum power and the optimum values of design variables were investigated for a wide range of UA(overall heat transfer conductance) change. The results show that maximizing heat source utilization does not always maximize power.