• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.119-123
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• 2005

The main purpose of this study is to define an optimum slope of the roof that demands minimum cooling load of the building, when the roof is affected by the solar and wind energy. Two different roof shapes were chosen: hip, gabled. The cooling load of building having those roof shapes was calculated through the computer simulation, using DOE program. For the simulation, the angle of the roof and angle of the orientation was changed. In the conclusion of this paper, an optimum slope of the roof which causes minimize cooling load is presented according to the roof shape and orientation. The result of this study could provide a practical design guideline for determining the roof angle for various climatic conditions.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.937-942
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• 2008

In this paper, new methodology is proposed to estimate the cooling load using design parameters of building and predicted weather data. Only two parameters such as maximum and minimum temperature are necessary to obtain hourly distribution of cooling load for the next day. The maximum and minimum temperature that are used for input parameters can be obtained from forecasted weather data. Benchmarking building(research building) is selected to validate the performance of the proposed method, and the estimated cooling loads in hourly bases are calculated and compared with the measured data for benchmarking building. The estimated results show fairly good agreement with the measured data for benchmarking building.

• 설비공학논문집
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• 제22권11호
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• pp.798-804
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• 2010

New methodology is proposed to predict the hourly cooling load of the next day using maximum/minimum temperature and building area. The maximum and minimum temperature are obtained from forecasted weather data. The cooling load parameters related to building area are set through a database provided from reference buildings. To validate the performance of the proposed method, the predicted cooling loads in hourly bases are calculated and compared with the measured data. The predicted results show fairly good agreement with the measured data for benchmarking building.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.440-445
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• 2008

In this paper, new methodology is proposed to estimate the cooling load using areas of building group and predicted weather data. Only three parameters such as maximum, minimum temperature and building area are necessary to obtain hourly distribution of cooling load for the next day. The maximum and minimum temperature that are used for input parameters can be obtained from forecasted weather data. The areas of building group are used for setting several parameters that are used for estimate cooling loads. Benchmarking building(research building) is selected to validate the performance of the proposed method, and the estimated cooling loads in hourly bases are calculated and compared with the measured data for benchmarking building. The estimated results show fairly good agreement with the measured data for benchmarking building.

• 대한건축학회논문집:구조계
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• 제35권10호
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• pp.235-243
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• 2019

In South Korea, millions of poultry have died due to repeated heat waves every year. The purpose of this study is to analyze the characteristics of heating and cooling loads of chicken houses in Korea and to present an effective insulation and ventilation measures to minimize the damage of poultry due to summer heat wave and to save energy in chicken houses in winter. The heating and cooling loads of standard chicken house were calculated. As a result of the calculation of maximum heating load based on the minimum ventilation rate in winter, the outdoor air temperature requiring heating was $6{\sim}7^{\circ}C$ to keep the indoor air temperature of chicken houses as $24^{\circ}C$. The peak cooling load of chicken houses was mostly taken by the heat generated by chickens and the heat gain due to ventilation. The heat gain through building envelopes was as small as neglectable. Most of chicken houses is usually cooled by gigantic forced ventilation in summer in Korea. When the chicken houses are cooled by electric cooling machine such as cooler or air conditioner, it is more effective to keep minimum ventilation rate to reduce the maximum cooling load. To lower the temperature of supplying water to cooling pad, it is recommended to use the underground water below 10 meters from the ground if there is abundant underground water.

• 대한기계학회논문집B
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• 제37권3호
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• pp.267-273
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• 2013

막충진재(film fill)를 갖는 냉각탑용 팬의 효율적인 운전조건을 제시하기 위하여, Merkel의 이론을 바탕으로 한 종전의 최적 총연간비용 모델을 사용하여 입구 물온도와 열부하에 따른 최소팬동력을 구하는 프로그램이 새로이 개발되었으며, 냉각탑의 설계 맵이 본 연구로부터 제시되었다. 전형적인 예들을 통하여 본 프로그램의 타당성이 입증되었다. 주어진 열부하에서 이들 팬동력(z 축)-공기질량플럭스(x 축, 최소팬동력 존재)-입구물온도(y 축, 최소팬동력의 최대값 존재)의 3차원 그래프는 말안장 형상으로 나타났다. 최소팬동력들은 열부하에 따라 증가하였다. 따라서, '고온수 유입과 저유량의 공기로 작동' 될 때가 항상 최소팬동력 조건이 아니며, '주어진 입구물온도에 대하여 최소팬동력에 대응하는 최적의 공기질량플럭스가 (열부하와 무관하게) 존재한다'는 사실이 본 연구결과로부터 밝혀졌다.

• 설비공학논문집
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• 제29권2호
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• pp.43-50
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• 2017

The purpose of this study is to develop a control algorithm for outdoor air cooling based on the prediction of cooling load, and to evaluate the building energy saving using outdoor air cooling. Outdoor air conditions such as temperature, humidity, and solar insolation are predicted using forecasted information provided by the meteorological agency, and the building cooling load is predicted from the obtained outdoor air conditions and building characteristics. The air flow rate induced by outdoor air is determined by considering the predicted cooling loads. To evaluate the energy saving, the benchmark building is modeled and simulated using the TRNSYS program. Energy saving by outdoor air cooling using load prediction is found to be around 10% of the total cooling coil load in all locations of Korea. As the allowable minimum indoor temperature is decreased, the total energy saving is increased and approaches close to that of the conventional enthalpy control.

• 설비공학논문집
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• 제24권11호
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• pp.759-766
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• 2012

To estimate the cooling load for the following day, outdoor temperature and humidity are needed in hourly base. But the meteorological administration forecasts only maximum and minimum temperature. New methodology is proposed for predicting hourly outdoor temperature and humidity by using the forecasted maximum and minimum temperature. The correlations for normalized outdoor temperature and specific humidity has been derived from the weather data for five years at Seoul, Daejeon and Pusan. The correlations for normalized temperature are independent of date, while the correlations for specific humidity are linearly dependent on date. The predicted results show fairly good agreement with the measured data. The prediction program is also developed for hourly outdoor dry bulb temperature, specific humidity, dew point, relative humidity, enthalpy and specific volume.

• 설비공학논문집
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• 제20권2호
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• pp.128-136
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• 2008

It is necessary to estimate the cooling load of the next day for effective control of ice thermal storage system. In this paper, new methodology is proposed to estimate the cooling load using design parameters of building and predicted weather data. Only six input parameters such as sensible heat coefficient and constant, latent heat coefficient and constant, maximum and minimum temperature are necessary to obtain hourly distribution of cooling load for the next day. Two benchmarking buildings(hospital and research institute) are selected to validate the performance of the proposed method, and the estimated cooling loads in hourly and daily bases are calculated and compared with the measured data for E hospital. The estimated results show fairly good agreement with the measured data for both buildings.

• KEPCO Journal on Electric Power and Energy
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• 제2권1호
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• pp.83-88
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• 2016

This paper describes the test results of plant minimum stable load (Pmin) for Ilijan Power Plant. The test was conducted on May 13 through 14, 2015 to investigate the plant operating and equipment condition in accordance with "Ilijan Plant Performance Test Procedure on Plant Minimum Stable Load" [1]. This paper also contains the assessment of the impact of Pmin to plant operating parameters and possible technical operating issues when operating at lower loads and to recommend the safe minimum load operation of Ilijan per block. In addition, this paper describes the performance calculation results of efficiency and heat rate depending on the load level.