• Journal of Advanced Marine Engineering and Technology
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• v.35 no.3
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• pp.335-340
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• 2011

Building energy saving is one of the most important issues in these days. Control algorithm for energy saving should be designed properly to reduce power consumption in building. Recently, building energy system consists of hybrid energy system coupling with RE (Renewable Energy) source. In this paper, an optimum control algorithm for building energy saving is applied to BEMS (Building Energy Management System) by using an outdoor air temperature prediction strategy. BEMS coupling with renewable energy can control HVAC (Heating, Ventilating and Air-Conditioning) system effectively. In order to verify the effectiveness of building energy saving, BEMS was tested for several months at a laboratorial chamber with an air conditioner, fan and heater. To this end BEMS embedded control algorithm has been tested successfully.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.3
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• pp.251-259
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• 2018

Metal hydride based hydrogen storage under moderate temperature and pressure gives the safety advantage over the gas and liquid storage methods. Still solid-state hydrogen storage including metal hydride is below the DOE target level for automotive applications, but it can be adapted to stationary or miliary application reasonably. In order to develop a modular solid state hydrogen storage system that can be applied to a distributed power supply system composed of renewable energy - water electrolysis - fuel cell, the heat transfer and hydrogen storage characteristics of the metal hydride necessary for the module system design were investigated using AB5 type metal hydride, LCN2 ($La_{0.9}Ce_{0.1}Ni_5$). The planetary high energy mill (PHEM) treatment of LCN2 confirmed the initial hydrogen storage activation and hydrogen storage capacity through surface modification of LCN2 material. Expanded natural graphite (ENG) addition to LCN2, and compression molding at 500 atm improved the thermal conductivity of the solid hydrogen storage material.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.64.1-64.1
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• 2010

In this study, the energy and economic analysis of KIER Zero Energy Solar House (KIER ZeSH) was carried out. KIER ZeSH was designed and constructed in the end of 2009 for the purpose of more than 70% energy self-sufficiency in total load as well as less than 20% of additional construction cost. The several building energy conservation technologies like as super insulation, high performance window, wast heat recovery system, etc and renewable energy system. The renewable heating and cooling system is a kind of solar thermal system combined with geo-source heat pump as a back-up device. The capacity of 3.15kW solar BIPV system was also installed on the roof. The measurement by monitering system of ZeSH was conducted for one year from November 2009 to October 2010. The energy self-sufficiency and economic analysis were conducted based on the this monitering result. As a result, the energy self sufficiency is about 83% which is higher than that of the target and the payback period is 11 years.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.306-309
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• 2008

Renewable energy information becomes one of the greatest issues, but it is difficult for a general user to manage and utilize new renewable energy information. Therefore we develop the utilization system of the resource map which aimed to provide the information for space analysis and vertification of the validity for development of each part of solar, wind, smallhydro, biomass, geothermal. But this system is needed to gather more supporting data and make resonable index to make various decisions.

• New & Renewable Energy
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• v.17 no.1
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• pp.33-39
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• 2021

The energy use is increasing as the quality of human life improves. and research on the efficient use of energy in ESS (Energy Storage System) is ongoing. An air conditioner is required for the efficient use of an ESS, as are data on the distribution of the temperature of the latter based on the capacity of the air conditioner. In the absence of an air conditioner, the battery of the ESS reaches its maximum temperature of 40℃ after 2 h. When an air conditioner is present, the temperature of the battery stabilizes as the capacity of the former increases.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.5
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• pp.2177-2193
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• 2018

This paper studies resource allocation schemes for the relay-aided cooperative system consisting of multiple source-destination pairs and decode-forward (DF) relays. Specially, relaying selection, multisubcarrier pairing and assignment, and power allocation are investigated jointly. We consider a combinatorial optimization problem on quality of experience (QoE) and energy consumption based on relay-aided cooperative system. For providing better QoE and lower energy consumption we formulate a multi-objective optimization problem to maximize the total mean opinion score (MOS) value and minimize the total power consumption. To this end, we employ the nondominated sorting genetic algorithm version II (NSGA-II) and obtain sets of Pareto optimal solutions. Specially, two formulas are devised for the optimal solutions of the multi-objective optimization problems with and without a service priority constraint. Moreover, simulation results show that the proposed schemes are superior to the existing ones.

• Journal of the Korean Solar Energy Society
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• v.32 no.5
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• pp.75-82
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• 2012

This study aims to investigate the usage of the renewable energy systems installed in buildings and make suggestions for the effective management. In this regard, a questionnaire survey was conducted on 1)design and construction, 2) operation and management, 3) user satisfaction and improvements about the renewable energy systems in buildings. Findings from this study can be summarized as follows; a lack of the basic information about systems, non-use of energy management systems, the differences in the features by energy source, and a lack of expertise of managers. The requirements to resolved these problems include the integrated management of various electric heat sources including a renewable energy source, an operation schedule based on the prediction of production and consumption, and so on. Furthermore the necessity of multiplex energy sources management system was confirmed and the basic data needed to establish the targets of this system were obtained.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.220-225
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• 2011

Based on the supply status statistics of new renewable energy according to public obligation system, current status of overall application centered on solar heat, solar ray, and geothermal heat as energy sources that can be applied to buildings may be analyzed as follows. (1) After the public obligation system, the investment costs on the total construction costs by years were between 5.21% and 7.12%: they were 7.12% in 2004, where the system was initially implemented; and they were gradually declined from 2005 to 2011, 5.76% in average. The ratio of equipment investment per energy sources in the total construction costs was 5.9%, which was slightly more than the obliged ratio. The order of investment costs per energy source was solar ray, geothermal heat, and solar heat. (2) Among the 1,433 sites in the plan of new renewable energy installation based on the public obligation system, "for cultural & social use" was most in target institution, and facilities for education & research was most in use classification, followed by public working, culture & rally, and sports. The number of facilities applied according to the case for planning installation per use classification of the target institution was between 1.1 and 1.5, or 1.4 in average of energy source. Conclusively, the authors of this study investigated overall current status of new renewable energy supply from the analysis of statistic data, and it may be needed of further supplementation of various examinations by visiting investigation and interviews with practitioners based on classification of use of target institutions.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.372-374
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• 2008

Korea classified into a development country when UNFCCC was concluded in 1995. So Korea doesn't have a GHG reduction duty until 2012. As the UNFCCC is strengthened, recently there is a growing interest in renewable energy and energy usage efficiency improvement for reducing GHG emission. It is associated with CES and renewable energy. CES is a total energy (heat, cooling and power)supplier in aggregated demand zone like a hotel, building, hospital and redevelopment district using CHP and it improves energy usage efficiency. At present, renewable energy is needed for GHG reduction duty but renewable energy doesn't have economic feasibility. So renewable energy is needed various support system to popularize which is a FIT and RPS. Especially RPS is carrying out instead of FIT in many advanced country and it will be inroduced in Korea. RPS is a duty which electricity service provider must guarantee renewable energy as much as specific ratio of total capacity. Therefore this study conducts an economic feasibility estimation of CES considering renewable energy when RPS will introduced in the future.

• 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.