• Journal of Environmental Science International
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• v.20 no.9
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• pp.1105-1114
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• 2011

In this study, thermal environment improvements throughout public design improvement project on the urban street space were compared and evaluated. Thermo-Render 3.0, 3D-CAD based thermal environment simulation program, had been used for thermal environment improvement evaluations. Followings are the results. First, clayey blocks which have low heat transfer rate and cool island effect by trees and roof gardens brought cooling effects for buildings and surface of streets. Seconds, MRT values showed low levels because of low radiant mulching materials. Thirds, roof gardens contributed to reduce heat island effect since HIP levels were affected by decreasing heat storage effect of buildings from roof gardens. As a result, reducing heat storage effect throughout selecting and arranging proper materials which would not increase heat island potentials should be performed to improve heat island effects.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.418-423
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• 1999

This study was performed to find an efficient method to overcome extremely high temperature within greehhouse in summer season. The actual states of practical use for greenhouse in hot summer season were investigated. About 21.6% of the investigated greenhouse farms were no cultivation, and most greenhouse farms were cultivating under the very inferior environment . To examine thermal enviornment of greenhouse according to cooling or assistant cooling , greenhouses were treated with natural ventilation, shading, roof sprinkling , and evaporative cooling with air cool fan. Shading and operating air col fan showed a drop in temperature of 3.8∼4.2$^{\circ}C$ as compared with natural ventilation, and most greenhouse air temperatures were maintained below 35$^{\circ}C$.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.6
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• pp.521-528
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• 2016

The surface of a naval ship emits infrared signature because it is mainly heated by the sun. In order to reduce infrared signature, it has been practiced to cool surface of the naval ship by using sea water. In this study, reduction effect of infrared signature was compared according to the parameters which affect emission of infrared signature in order to increase utility of sea water cooling. The analysis results by searching parameters, which can judge operation of sea water cooling, could be utilized as basic data for operation of the naval ship.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.12 no.3
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• pp.189-197
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• 1983

In this study, the thermal environment of a certain building was investigated by using of concerned equipments and enquete sheets. The measured items were temperature, humidity, air flow and radiant heat, and thermal responses for the occupants were checked also, which are oriented to be used as basic data for environmental design. The results of this study are as followed. 1. The optimal room temperature was $24\~26.5^{\circ}C$ DBT in cooling season. 2. Under the condition from $50\%\;to\;70\%$ of relative humidity, the difference of relative humidity did not impact upon the feeling temperature. 3. In cooling season, the average clothing factor of occupants was 0.34 clo ; 0.49 clo for men and 0.25 clo for women. 4. The average working factor of occupants was $1.1\~1.3\;Met$ in that cooling season.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.983-993
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• 2022

The purpose of this study is to provide information on a forest healing environment using the analysis of nature volatile organic compounds (NVOCs) and thermal comfort in Chungnam National University Experimental Forest, with the aim of using the Experimental Forest as a healing environment for health promotion. We analyzed NVOCs and thermal comfort of Chungnam National University Experimental Forest measured on September 12^th, 2021. As a result of the NVOC analysis, a total of seven substances were detected, mainly including alpha pinene and beta pinene. The detection amount for each time period was highest at the time of sunset. The thermal comfort was analyzed by time-dependent changes and changes according to clothing and exercise amount. The results showed that the predicted mean vote of the experimental forest is within the range of 'slightly cool' and 'slightly warm' sensation, and thus a comfortable thermal environment could be controlled by the amount of clothing and activity. Based on the analysis, this study provides information on the healing environment of the experimental forest at Chungnam National University. It also indicates that the forest can be used as a health promotion and healing environment with thermal comfort by composing a physical activity program of appropriate intensity for each time period.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.1
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• pp.1-9
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• 2013

The experimental study of the white LED lighting focused on the readability in interior space according to age group is conducted realizing importance of the lighting environment and necessity of lighting study depending on the user situation. The results of study represent that a teenager does not show sensitive reaction to change of the color temperature and illuminance. The people in 20s and 30s prefer neutral white LED lighting and are very sensitive to change of the light environment. The people in 50s and 60s prefer high illumination and cool white LED lighting series. People of all ages highly appraise 6000K of 700 lux and 4000K in the illuminance range of 700 lux to 1000 lux for readability. The white LED lighting of color temperature 4000K is estimated as a suitable environment for readability in a wide range of illumination.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.137-146
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• 2007

This study is about the passive cooling effects of three outdoor solar shading facilities as trees, pergola with wistaria vine and membrane shading structure, which are expected to provide cool spots in the summer. Field observations of measuring thermal environment of selected facilities is executed. Thermal environment measuring was categorized as short wave radiation, long wave radiation, net radiation, globe temperature, surface temperature measured by infrared camera. Heat transfer mechanism is analyzed with overall data from field measurement. Results from this study are as below; 1) Radiation balance measured on shaded surface under membrane shading structure was 17%($86W/m^2$) of the unshaded surface radiation balance($511W/m^2$). 2) Surface temperature comparison between vegetation and membrane of the shading structure is performed at 3 o'clock in the afternoon. Surface temperature of vegetation was same as air temperature and that of membrane was $5^{\circ}C$ higher than air temperature. Vegetation transpiration is considered as the causing factor which make those differences. 3) Results from this study could be used as fundamental data for reducing heat island phenomena and continuos research on this subject would be needed.

• Progress in Superconductivity and Cryogenics
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• v.11 no.3
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• pp.65-68
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• 2009

The Stirling cryocoolers have been widely used for the cooling of the infrared detector(InSb, HgCdTe, and etc,) and HTS(High Temperature Superconductor) to the cryogenic temperature. The monobloc Stirling cryocoolers with the rotary compressor are applicable to the cooling device for the compact mobile thermal imaging system, because the cryocoolers have the compact structure and light weight. The typical performance factors of the Stirling cryocooler are the cool-down time, cooling capacity at the desired temperature (80 K), the electric input power and COP. The above performance factors depend on the operating conditions such as the charging pressure of the helium gas, the thermal environment and etc.. In this study, the effects of the thermal environment (temperature of 241, 293, and 333 K) on the performance of the cryocooler were investigated by experiments. The results show the effects of the temperature of the thermal environment on the cooling capacity and input power.

• Korean Journal of Medicinal Crop Science
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• v.24 no.4
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• pp.277-283
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• 2016

Background: The photosynthetic efficiency cool-season, semi-shade ginseng is normal at low morning temperatures, but drops at high afternoon temperatures. Therefore, optimal plant performance would be ensured if it were possible to control daily light transmission rates (LTR). Methods and Results: Plants were grown in a controlled light environment that replicated 11 AM conditions and comparatively analyzed against plant grown under normal conditions. Growth in the controlled light environment resulted in a 2.81 fold increase in photosynthetic efficiency with no change in chlorophyll content, although LTR were high due to low morning temperatures. Increased aerial plant growth was observed in the ginseng plants adapted to the controlled light environment, which in turn influenced root weight. An 81% increase in fresh root weight (33.3 g per plant on average) was observed in 4-year-old ginseng plants grown in controlled light environment compared to the plants grown following conventional practices (18.4 g per plant on average). With regard to the inorganic composition of leaves of 4-year-old ginseng plants grown in controlled light environment, an increased in Fe content was observed, while Mn and Zn content decreased, and total ginsenoside content of roots increased 2.37 fold. Conclusions: Growth of ginseng under a favorable light environment, such as the condition which exist naturally at 11 AM and are suitable for the plant's photosynthetic activity creates the possibility of large scale production, excellent-quality ginseng.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.6
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• pp.983-991
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• 1996

This study focusses on how the skirt or slacks wearing habit affects the female physiology in her daily life. The healthy female college students have been trained to wear either skirt (group A) or slacks (group B) from late August to early January in order to study the effects of clothing habit on thermoregulatory responses. Also, the themoregulatory responses have been compared the healthy students groups with a physical trained students group (group C) to examine the effects of clothing habit. The changes in body temperatures of students have been studied under the cool environmental condition (15$\pm$1$^{\circ}C$, 60$\pm$5% RH, 0.25 m/sec). The results were as follows: 1. Rectal temperature of the group A was 0.4$^{\circ}C$ lower at 36.9$^{\circ}C$ than that of the group B The groups A and B were found identical before the training, while the groups A and C were identical after the training. 2. Mean skin temperature of the group A was 1.2$^{\circ}C$ lower than that of the group B. The groups A and C were identical after the training. 3. The thermal sensation was reflected to be cool by the group A and to be cold by the group B. As for the humidity sensation, the group A felt average, whereas the group B reported between average and slightly humid. In the case of comfort sensation, the group A felt average, while the group B felt between average and slightly uncomfortable. In summary, the 18 weeks of training has provided the skirt group an improved acclimatization to the cold environment . This group also showed an insulative-hypothermic adapta lion in a cold ambient temperature, as was the case for the physical trained group. It is concluded that wearing a skirt for a long period of time can be helpful to human body through gaining of thermoregulatory abilities.