• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.308-310
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• 2005

In recent years, the research and development for the photovoltaic(PV) energy system are making rapidly progress around the world and specially this country, too due the deregulation law for the renewable energy system seems to be born sooner or later. In PV generation system, the partially shaded PV array is the one of the worst case which reduces the efficiency of the total PV generation system. The partial shaded condition is the result of shadowing by cloud and dust building of on the surface of the panel. Some structural elements, such as antennas, booms etc. is also the reason of the shadowing. Even if only a small part of PV is shaded, the overall generation power of PV is significantly decreased. Therefore, several researchers who are focusing on the PV generation system take a time for the research related with the shadowing problem of PV array. In this paper, authors have developed the method which users can achieved the modeling of partially shaded PV array with. With several papers authors have already announced the availability of the EMTDC/PSCAD PV panel model component. This research result is the developed version of the previous papers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1148_1149
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• 2009

반사형 전동 블라인드는 BEMS(Building Energy Management System)에 이용되는 조명 에너지 절감 장치로서, 블라인드 날개를 반사형 재질로 제작하여, 외부 채광이 블라인드 날개에 반사되어 천장에 반사되고 반사된 빛은 천장에서 확산되어 실내 깊숙이 부드럽고 균일한 조도를 공급해 준다. 이를 이용하면, 실내 거주자의 불편함 없이 실내 인공조명 사용량을 줄일 수 있다. 이를 구현하기 위해서는 태양광선의 고도의 변화에 따라 블라인드의 제어 각도를 계산하여 블라인드 제어 전동 모터를 구동해야 한다. 따라서 본 논문에서는 외부 채광을 실내 천장 면에 균일하게 반사할 수 있는 블라인드 날개의 제어 각도의 최적 조건을 제시하고, 컴퓨터 시뮬레이션을 통해 제시한 블라인드 날개 각도의 최적성을 검증하였다.

• 한국컴퓨터정보학회논문지
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• 제22권12호
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• pp.27-34
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• 2017

Design of an intelligent controller for efficient control in smart building is one of the effective technologies to reduce energy consumption by reducing response time with keeping comfortable level for inhabitants. In this paper, we focus on how to find major parameters in order to enhance the ability of HVAC(heating, ventilation, air conditioning) PID controller. For the purpose of that, we use machine learning technologies for tuning HVAC devices. We show the simulation results to illustrate the behavioral relation of whole system and each control parameter while learning process.

• 인터넷정보학회논문지
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• 제19권1호
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• pp.123-130
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• 2018

With the emergence of a new paradigm called Open Science and Big Data, the need for data sharing and collaboration is also emerging in the computational science field. This paper, we analyzed data-driven research cases for computational science by field; material design, bioinformatics, high energy physics. We also studied the characteristics of the computational science data and the data management issues. To manage computational science data effectively it is required to have data quality management, increased data reliability, flexibility to support a variety of data types, and tools for analysis and linkage to the computing infrastructure. In addition, we analyzed trends of platform technology for efficient sharing and management of computational science data. The main contribution of this paper is to review the various computational science data repositories and related platform technologies to analyze the characteristics of computational science data and the problems of data management, and to present design considerations for building a future computational science data platform.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.140-146
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• 2008

A friction damper is installed in the passenger car driveline in order to dissipate the torsional vibration energy. The frictional damping hysteresis has considerable influences on the driveline vibration characteristics and, therefore, it is one of the most important parameters in the damper design. To investigate the hysteresis effects on the driveline vibration, a dynamic model of the passenger car driveline with manual transmission has developed, and simulations were executed on the several different driving conditions for various hysteresis values. To verify the model, vehicle tests are preformed and the test data were compared with the simulations results. The simulation and test results show good agreements and the model could be used to determine the optimal hyteresis values in early design stage of the damper.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.457-462
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• 2005

In this study, the performance of automatic thermostatic valves according to each heating method of a large scale residential building were researched by simulation. The flow characteristics of the entire pipe networks of the hot water radiant heating system is analized by using linear analysis method. For the analysis of unsteady heat transfer phenomena in each household, the method of using electric equivalent R-C circuit is applied.

• 설비공학논문집
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• 제23권3호
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• pp.216-222
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• 2011

Recently, hybrid air-conditioning system has been proposed and applied to achieve building energy saving. One example is a system combining radiation panel with natural wind-induced cross-ventilation. However, few research works have been conducted on the non-uniformity of thermal comfort in such hybrid air-conditioning system. In this paper, both thermal environment and non-uniform thermal comfort of human thermal model under various air-conditioning system, including hybrid system, were evaluated in a typical office room using coupled simulation of computation fluid dynamics, radiation model and a human thermal model. The non-uniformity of thermal comfort was evaluated from the deviation of surface temperature of human thermal model. Flow fields and temperature distribution in each case were represented.

• 설비공학논문집
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• 제22권2호
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• pp.57-63
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• 2010

Air curtains are widely used for gates of shopping mall, warehouse, cold stores and refrigerated display cabinets. The purpose of the air curtain is to reduce the infiltration of outdoor air and heat loss from the air conditioning space to ambient air. The discharge angle of air curtain is very important as the sealing efficiency is affected by it. This paper presents a performance of single jet air curtain in heating space when the discharge angle of nozzle changes. A numerical simulation is used to study the influence of various parameters on the efficiency of the downward-blowing air curtain device which is installed inside of the wall above the door. The performance of the air curtain is evaluated by sealing efficiency which provides the assessment of the energy savings. A condition of discharge angle that has the highest sealing efficiency is proposed.

• 한국주거학회논문집
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• 제15권3호
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• pp.73-82
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• 2004

The objective of this study is to demonstrate the potential of radiant cooling systems using Ondol as an alternative cooling system in residential buildings. For this purpose, computer simulation and model experiments have been performed for the system performance analysis regarding comfort, floor surface condensation, and supply water temperature. The results of this study is the following: In radiant floor cooling system, room air temperatures were maintained within the set temperature range of $\pm$1$^{\circ}C$ without any discomfort condition. And taking into account only the condensation occurrence, it was possible to achieve radiant floor cooling for a period of about 77% of the total cooling period in weather condition of Seoul. The minimum supply water temperature is about 15$^{\circ}C$, so renewable energy system such as ground heat exchange system can be used as an alternative in cooling source. Also, floor surface condensation can be prevented by integrating with the dehumidification system.

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.254-262
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• 2008

This paper presents an active use of doubly-fed induction-generator(DFIG)-based variable-speed wind-turbine for voltage control in power system operation. For reasonable simulation studies, a detail dynamic model of a DFIG-based wind-turbine grid-connected system is presented. For the research objective, an innovative reactive power control scheme is proposed that manipulates dynamically the reactive power from the voltage source converter(VSC) with taking into account its operating state and limits.