• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.5
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• pp.334-341
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• 2008

The purpose of this study is to investigate the effects of changing air temperature and the changing on/off periods of the air-conditioner system. Adding to that, this paper discuss is to consider the effects of air temperature with the air-conditioner system upon the human thermal comfort. The experiment is conducted during the summer. The subjects(6 young females) are exposed to the following conditions: combinations of 2 Swing and 2 Linear air control Conditions. (2 Swing during 40 min, 4 Swing during 40 min, Linear 40 min, Linear 60 min in still air and RH 50%). From the experiment, the following results are obtained; the thermal sensation vote is neutral after 90 minute. The mean skin temperature ranged about $34^{\circ}C$ at all conditions. The skin temperature was greatly affected by 2 Swing big amplitude condition.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.230-234
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• 2000

Thermal comfort by wearing clothes is the important element which gives influence to a clothing comfort. The thermal comfort of clothes have been evaluated by sensory test and physical property of clothes material. To evaluate a thermophysiological comfort. a new evaluation method which measures the physiological response such as electroencephalogram(EEG) is attracting the attention of many people. In the chilly environment, the EEGs in t재 kinds of thermal conditions : with and without clothes were measured. By utilizing the chaos analysis, the behavior of the obtained EEGs were quantiatively expressed in the correlation dimension. As a result, the correlation dimension of the EEGs in being thermal comfortable feeling by putting on clothes, was bigger than the correlation dimension of the EEGs in being cold and discomfort. These results suggest that chaotic analysis of EEG is effective to the quantitative evaluation of thermal esthesis.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.6
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• pp.721-731
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• 1998

Recently, many researchers are studying the relation between thermal environment and human comfort. The purpose of this study was to obtain basic data which are necessary to determine the thermal comfort sensation and physiological responses for men in winter indoor environment. From January to February 1998, subject experiment was 40 times proceeded under twenty different conditions of air temperature and relative humidity with early-twenty male university students. We examined subjective evaluation, Electrocardiogram(ECG), Electroencephalogram(EEG) of subjects. The results of this study can be summarized as follows : The comfort zone of people in winter was achieved at Standard new effective temperature($SET^*$) $ 25.2^{\circ}C$, PMV range was obtained by Fanger's statistical calculation was －0.27＜PMV＜＋0.62, TSV range obtained subjects vote was －0.76＜TSV＜＋0.36. The largest difference of skin temperature was found at the calf area as air temperature changes. vote rate of human body presented calflongrightarrowheadlongrightarrowforearmlongrightarrowchestlongrightarrowabdo men in turn. Heart rate was decreased at low $SET^*$ and heart rate was increased at high $SET^*$ But there was no change at EEG.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.455-460
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• 2004

This study was performed to analyze the wearing practice and the purchasing characteristics of brassieres in order to offer basic data to produce superior brassiere and to improve the wearing comfort. The questionnaire were 146 Korean college female students. For data analysis, descriptive analysis, crosstabs, factor analysis and one-way ANOVA were used. The results were as follows, first, most subjects didn't know the sizing system of brassiere and their own breast size. So the degree of satisfaction of wearing brassiere was low than subjects who knew their own breast size. And they replied that the most unsatisfaction factor was brassiere size. Second, when subjects decided to purchase a brassiere they considered size, design, color, cost, fabric and brand and so on. Among them size and design were considered the most important. Third, the subjects who wear brassiere all day long, they considered wearing comfort and cost rather than design and collar. Therefore, the markets with brassieres would be able to segmented based on consumers' characteristics. Firth, the subjects were dissatisified at size, the taking off wire and shape modification after washing. And they requested the development of various size, fabric and cost improvement and fittness of brassieres. These results imply that to improve the wearing comfort of brassiere, it is so important to produce and develop various types of size first of all. And consumers should know size system of brassiere and their own breast size.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.11
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• pp.711-717
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• 2008

Despite the fact that UFAD(Under Floor Air Distribution) systems have many benefits and are being applied in the field in increasing numbers, there is a strong need for an improved fundamental understanding of several key performance features of these systems. This study numerically investigates the effect of supplied air temperature and supplied flow rate on the performance of UFAD, especially focused on thermal comfort. Also this study has compared UFAD with conventional overhead air distribution system. In contrast to the well-mixed room air conditions of the conventional overheat system, UFAD system produces an overall floor-to-ceiling airflow pattern that takes advantage of the natural buoyancy produced by heat sources in the occupied zone and more efficiently removes heat loads and contaminants from the space. Thermal comfort parameters were evaluated by CFD approach and then PMV was computed to detect the occupants' thermal sensation. Results show that radiative mean temperature plays crucial role on the evaluating PMV. Until now, the radiative temperature has been the missing link between CFD and thermal comfort, but the present study paves the way for overcoming this weakness.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.3
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• pp.501-510
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• 2024

This study aimed to compare the cooling effect of specific body parts to increase workers' thermal comfort. The parts to be cooled comprised the head and neck; the coolant was a phase change material. The participants were ten men in their 20s of average size according to the 8th Size Korea. The experiment was conducted under the following conditions: 28.0 ± 0.5℃, 60.0 ± 5.0% RH, and 0.2 ± 0.1m/s. The exercise consisted of participants moving for 15 min at a constant speed of 80 BPM; later, a subjective sensation was performed, and the clothing surface temperature was measured. In doing so, heat, wetness, and discomfort after exercise were confirmed to have increased without a coolant. Significant differences over time appeared only when no coolant was used, showing that thermal comfort decreased. Despite the addition of coolant, the clothing surface temperature gradually increased over time, but it decreased with coolant rather than without it. Therefore, additional coolant areas, a lower temperature, and simultaneous cooling convection were required to improve thermal comfort.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.1
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• pp.61-69
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• 1991

In order to investigate the comfort properties of aerobic wear with different materials, the physiological responses, subjective wear sensation and microclimate were measured. The experimental garment were all-in·one type with half·length sleeves made of cotton/ polyurethane and nylon/ polyhrethane fabrics. The conditions of the experimental room were controlled to maintain two type of environ- ments, i.e. $25{\pm}1^{\circ}C$, $60{\pm}5\%$ R. H. and $30{\pm}1^{\circ}C$, $70{\pm}5\%$ R.H., Air velocity was maintained at 0.25 misec all the time. The results are as follows; 1) At $25^{\circ}C$, mean skin temperature and comfort sensation were not significantly different among 2 types of materials. 2) At $30^{\circ}C$, aerobic wear made of cotton/polyurethane fibers showed better pleasant tactile sensation than that of nylon/polyurethane fibers. 3) Under both environmental conditions, microclimate of two types of aerobic wear was not significantly different. 4) Among several aspects of wear sensations, tactile sensation was the most powerful factor to differenciate material differences of aerobic wear.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• Journal of the Korean Home Economics Association
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• v.33 no.1
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• pp.203-210
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• 1995

The purpose of this study was to investigate the weights of clothing that middle school girl students are wearing and ghow athe students evaluate their comfort sensations for the state-of-clothing and classroom conditions. The results obtained were as follows. 1. Average total weights of clothing of each month were 795.5g/m2 for May(23.4$^{\circ}C$), 539-590.6g/m2(26.0-31.2$^{\circ}C$) from June to August, 723.6g/m2 for September(25.6$^{\circ}C$) and 980.2g/m2 for October(24.$0^{\circ}C$). 2. Total weight was changed markedly from May to June and from september to October. The change was mainly by tops. Not much change was observed for the bottoms due to the fact that students were blue jeans irrespect of the environmental conditions. 3. Not significant relationship was observed between clothing weights adn comfort sensations. When the classroom temperature was 23.4$^{\circ}C$, more than 50% of the students answered comfortable. 4. Negative correlation was observed between amount of bottoms weight and Rohrer Index; in other words, fat students were less bottoms such as pants of skirts. 5. Negative correlation was observed between physical finess and amount of under shirts at the month of May, June and October; students with igher physical fitness scores wear less under wear when the environmental temperature changes.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.8
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• pp.939-946
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• 2007

The purpose of this study is to measure and analyze the ship's indoor thermal conditions and also to integrate experimental database of those, supplied and controlled by ship's HVAC. On this study, temperature, humidity and air volume of 6 different needs' cabin are measured on a newly-launched training ship during 2nd through 5th of April, 2007. Followings are the results of this study. (1)Because only partial loads are needed in spring season, the air volume from diffusers are measured as below 20%. (2)The temperatures are ranged between $20{\sim}25^{\circ}C$ and those are within comfort temperature range proposed by AHREA. (3)But humidities in cabins are very low and it could be the reason of a cold and/or a skin disease. (4)From the student cabins' measurements which have different supply diffuser(s), it is clear that the design is suitable for this case. (5)Because of low humidity, only 16.1% among the measured data are satisfied with the comfort standard range proposed by ASHREA. To improve the predictability and the comfort, HVAC should maintain the humidity as $40{\sim}60%$.