• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.1
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• pp.7-12
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• 2019

Clouds in the atmosphere are important variables that affect the temperature change by reflecting the radiant energy of the earth surface as well as changing the amount of sunshine by reflecting the sun's radiation energy. Especially, the amount of sunshine on the surface is very important It is essential information. Therefore, eye-observations of the sky on the surface of the earth have been enhanced by satellite photographs or relatively narrowed observation equipments. Therefore, cloud automatic observing systems have been developed in order to replace the human observers, but depending on the seasons, the reliability of observations is not high enough to be applied in the field due to pollutants or fog in the atmosphere. Therefore, we have developed a cloud observation algorithm that is robust against smog and fog. It is based on the calculation of the degree of aerosol from the all-sky image, and is added to the developed cloud reader to develop season- and climate-insensitive algorithms to improve reliability. The result compared to existing cloud readers and the result of cloud cover is improved.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.130-133
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• 2012

The Korea Institute of Energy Research(KIER) has began collecting solar radiation components data since January, 1988, and solar radiation classified wavelength data since November, 2008. KIER's solar radiation components and classified wavelength data will be extensively used by concentrating solar energy system users or designers as well as by research institutes.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.17 no.3
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• pp.1-12
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• 2021

In this study, the effects of various operational conditions for floor radiant heating system were researched by experiments. Hot water supply set temperature, indoor air set temperature and supply water flowrate were considered as operational conditions. The control method for this system is On-Off control of automatic thermostatic valve. The purpose of this study is to evaluate indoor thermal control characteristics and energy performance, respectively. As a result, if lower supply water temperature is applied, the supply and return temperature difference is reduced and energy consumption of heat supply is also reduced.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.4
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• pp.13-19
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• 2018

The Effects of hot water supply temperature on indoor thermal characteristics for floor radiant heating system in residential apartment were researched by computer simulation. The parametric study on hot water supply temperatures with different outdoor air temperatures was done with regard to energy performance and control characteristics, respectively. As a result, the maximum overshoot of indoor air temperature and energy consumption were reduced by adjusting the hot water supply temperatures with outdoor air temperatures.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1255-1256
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• 2007

전도, 대류, 복사 방식의 열전달 방식중에서 복사방식이 가장 효율적이고 쾌적한 난방이라는 것은 기존의 연구에서도 잘 알려진 사실이다. 본 연구에서 제안한 천장형 원적외선 복사난방 방식은 같은 면적에서 같은 전력을 투입하였을 때, 설정온도 도달시간이 기존의 전기 난방기 보다 약 $10{\sim}20$분 빠르게 도달함을 알 수 있으며, 그만큼 에너지절약이 된다는 것을 알 수 있었다.

• Journal of the Korean Solar Energy Society
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• v.31 no.3
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• pp.133-144
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• 2011

The objective of this study is to analyze the characteristic of radiation environment in the urban and rural through the field observation in the summer. The radiation balance was compared through the measurement of the shortwave radiation and long-wave radiation in the urban, sub-urban, and rural. The following conclusion could be obtained from this research. (1)In the results of observation including the rain-day, it was found that the short wave radiance in the urban is lower about 10% than the rural. (2)The upper part of atmosphere layers in the urban are aabsorb much short wave radiation energies compared with the rural relatively. It can increase the temperature of the upper part of atmosphere layers and the emittance of long wave radiation. (3)The ratio of the downward short wave radiation to the downward long wave radiation was 1.24 for the urban, 1.28 for sub-urban and 1.35 for rural. It can be estimated that the atmosphere condition of the rural is better than that of other areas. (4)The net radiation of the rural was lower that of the urban. It was found that the energy in and outflow of the rural is easier than that of the urban. (5)The temperature variation for the long-wave radiation change of the rural showed more sensitive than that of the urban. It was came from the radiation characteristics of the surrounding environment and can be used as the important index to evaluate the thermal environment characteristic of urban.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.223-229
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• 2014

This study investigated the explosion characteristics of HCNG fuel using a simulation tool. The damage caused by the storage container explosion and vapor cloud explosion in a gas station was predicted. In case of an vapor cloud explosion in the HCNG station, 50~200kPa explosion pressure was predicted inside the station. When the cylinder explosion was occurred, in case of hydrogen, the measured influential distance of overpressure was 59m and radiant heat was 75m. In case of CNG, influential distance of overpressure was 89m and radiant heat was 144m would be estimated. In case of 30% HCNG that was blended with hydrogen and CNG, influential distance of overpressure was 81m and radiant heat was 130m were measured. The damage distance that explosive overpressure and radiant heat influenced CNG was seen as the highest. HCNG that was placed between CNG and hydrogen tended to be seen as more similar with CNG.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.466-473
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• 2016

In a shipbuilding process, thermal damage to the ship structure at the rear end results from an excessive heat input and conduction during welding process. To prevent such damage, appropriate control of the heat input, based on welding temperature measurement, is required. For temperature measurement, contact and non-contact methods are available; the thermography system is a popular non-contact temperature measurement. When the intensity of radiation from a high-temperature object is excessive, however, detecting the sensors of ordinary thermography systems leads to an inability in measuring the temperature due to saturation. Hence, this study suggests use of a neutral density filter that prevents an excessive amount of radiation from being accumulated in a thermography system, and thus makes it possible to quantitatively measure an object's temperature as high as $3000^{\circ}C$.

• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.71-81
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• 2012

This study for the understanding of the radiation environment according to the altitude in urban area in the summer observes the long and short wave radiation environment at the 4 urban areas with different height and the 1 suburban area. The results of this study are as follows. (1) When the altitude was high, the more short wave radiation was observed. (2) As the altitude was high, the temperature of atmosphere got lower. And because of that the downward long wave radiation was also lower. This general trend was confirmed through the study. (3) Through the observation of long wave radiation, the upper atmosphere of suburban area had the atmosphere characteristic which the temperature was rising and decreasing faster. Therefore, the difference radiation characteristics between the urban and suburban area were confirmed. (4) The result of the ratio of short wave radiation to long wave radiation(short wave radiation/long wave radiation) according to the altitude and location, the value was increased when the distance was far from the artificiality structure or a heat source, and the urban effect became smaller. Thus, it is expected that the ratio will be an evaluation index for evaluating urbanization effect.

• Journal of Energy Engineering
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• v.13 no.4
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• pp.291-295
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• 2004

Heat regenerator attached in small-scale regenerative radiant tube burner was designed using the theoretical computation code and was confirmed the performance of waste heat recovery ratio. From the computation, when ceramic ball of 4-5kg was used, temperature efficiency and available waste heat recovery ratio were predicted 80% and 70%, respectively. Similar efficiencies were obtained from the experiments using LPG. However, since exhaust gas temperature entered into regenerator was below 850$^{\circ}C$ which was moth lower than that we expected. air preheating temperature was lowered below 800$^{\circ}C$.