• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.43 no.12
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• pp.88-94
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• 2014

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.197-204
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• 2023

Heat stress causes a decrease in immunity and disease occurrence in livestock, increasing mortality and impairing productivity. In particular, chickens are very vulnerable to high temperatures compared to other livestock species because their entire body is covered with feathers and sweat glands are not developed. Currently, air conditioning systems are essential in broiler houses to prevent high-air temperature damage to broilers, but conventional cooling facilities are greatly affected by the external environment, so there are limits to their use. In this study, to propose a cooling method, thermal insulation paint and a heat pump were apply in the broiler houses to evaluate the temperature reduction effect. The heat pump experiment was to analyze the cooling effect according to the change in ventilation rate and propose an appropriate. As a result of the experiment, the heat-insulating paint reduced the temperature of the broiler houses by maximum 1-2℃, and in the broiler houses where the heat pump was operated, the temperature decrease was the largest when the ventilation rate was the lowest. When the air temperature in the house is similar to or lower than the outside air temperature, it is considered to be most effective to use a heat pump while maintaining only the minimum ventilation rate.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1995.04a
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• pp.55-56
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• 1995

작물의 생육환경을 계측하기 위한 환경 센서는 공업용으로 이용되는 센서들과는 달리 작물의 적정 생장환경 범위 내에서의 정확도와 안정성이 중요하고, 온실 환경에 대한 내구성 및 신뢰성이 요구되며, 가격이 저렴하고, 소형ㆍ경량화가 이루어져야 한다. 또한, 생장환경 변화로써 작물의 생장량을 증대시킬 수 있도록 하기 위해 생장환경 자료를 수집ㆍ분석할 수 있는 시스템도 필요하다. (중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.7
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• pp.621-627
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• 2013

Field tests of hybrid desiccant cooling systems were conducted from July to August 2011. Data were monitored and transferred in real time over the Internet. The monitored variableswere analyzed to determine the performance characteristics under outdoor conditions. A series of system simulations has been conducted for outdoor conditions of the field tests. The results agree well with the experimental data in general. The system performance has been shown to deteriorate for wetter conditions, as predicted by the simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5877-5884
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• 2014

Recently, abnormally cold weather has been reported more frequently in winter due to the climate change and abnormal weather changes. On the other hand, the heating capacity of a railcar may be not enough to warm the cabin under severe cold climatic conditions, which is one of the reasons for the passengers' complaints about heating. In this study, the effects of ambient temperature and heater power on the cabin temperature was investigated to obtain the minimum ambient temperature for the tested railcar. The test railcar was placed in a large-climatic chamber, and various ambient temperature conditions were simulated. The effects of the heater output were investigated by monitoring the cabin temperature under a range of heater output conditions. The mean cabin temperature was $14.0^{\circ}C$, which was far lower than the required minimum temperature of $18^{\circ}C$, under a $-10^{\circ}C$ ambient temperature condition with the maximum heat power. When the ambient temperature was set to $0^{\circ}C$ and $10^{\circ}C$, the maximum achievable cabin temperature was $26.1^{\circ}C$ and $34.0^{\circ}C$. Through calculations using the interpolation method, the minimum ambient temperature to maintain an $18^{\circ}C$ cabin temperature was $-6.7^{\circ}C$ for this car. The vertical temperature difference was higher with a higher power output and higher ambient temperature. The maximum vertical temperature difference was higher than $10^{\circ}C$ in some cases. However, the horizontal temperature difference vs. low temperature (< $2^{\circ}C$) was independent of the power output and ambient temperature. As a result, it is very important to reduce the vertical temperature difference to achieve good heating performance.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.2
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• pp.32-40
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• 2004

지구환경보호 관점에서 건물공기조화도 에너지 절감과 쾌적한 실내환경을 실현하는 것이 요구되고 있다. 본고에서는 BAS(빌딩오토메이션)로 실현하는 쾌적환경과 에너지 절감제어 응용에 관하여 소개하기로 한다. 쾌적한 에너지 절감제어 쾌적제어 (1) 협조제어 쾌적, 에너지절감, 운영경비절감 등 다양한 목적을 조화롭게 실현하는 제어이다. 예를 들면 쾌적하고 에너지절감제어에서는 여름철 냉방이나 겨울철 난방을 하는 경우에 있어서 무효한 에너지 사용을 억제하면서 실내환경을 유지하는 방법이다.(중략)

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.5
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• pp.29-36
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• 2017

In this study, a numerical analysis is made of the fluid flow and heat transfer characteristics in the solar arrays of HALE (High Altitude Lond Endurance) UAV. In the stratosphere where UAV operates, high level solar radiation is induced, heat transfer decreases due to natural convection and forced convection is dominated by ambient flow. In order to predict the solar array temperature range in this environment condition, the conjugate heat transfer analysis was carried out for the solar arrays on the main wing. The investigation focused on the temperature distribution of solar array and heat transfer characteristics according to influence of solar energy, flight condition as vehicle speed, air density, temperature.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.7
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• pp.571-579
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• 2014

A series of field tests on hybrid desiccant cooling systems were conducted in July-August, 2013. The temperature and humidity of the supply and return air, power, and heat consumption were monitored and transferred in real time through the Internet. The performance parameters of the cooling system, namely, cooling capacity and COP (coefficient of performance), were evaluated from the measured data and their variations under outdoor conditions was analyzed. It was found that with increase in the outdoor temperature, the total energy decreases and cooling capacity increases whereas the latter decreases with increase in the outdoor humidity. The COP was also found to increase with the increase in outdoor temperature.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.11
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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.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.39 no.3
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• pp.14-17
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• 2010

실내공간의 필터로도 제거되지 않는 미세한 오염물질 때문에 적절한 외기 도입은 필수적이다. 이에 한미설비(주)에서는 소비자들의 욕구에 합당하는 실내환경을 유지하기 위한 장치의 하나인 IAQ 댐퍼 유닛을 개발하였고 이를 소개하고자 한다.