• Journal of the Korean Home Economics Association
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• v.46 no.1
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• pp.39-45
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• 2008

We analyzed the effects of regular Jjimjilbang(Korean sauna) exposure on the physiological responses in seven elderly farmers(Male=3, Female=4). Jjimjil training group took a bath in Jjimjilbang 8 times twice a week. Jjimjibang exposure was limited three times per day. Rectal temperature, total sweat rate, body fat (%), blood pressure, pulse, $Na^+$ concentration in sweat, and subjective sensation were measured during Jjimjil training exposure. The results are as follow: During Jjimjil exposure, changes of rectal temperature in male farmers were more stabilized than female farmers. The gradual decrease in total sweat rate and Na+ concentration in sweat was observed in both sexes. After Jjimjil exposure, the decrease in blood pressure was observed in both sexes, but not observed changes according to regular Jjimjil exposure. Subjective thermal comfort sensation was changed positively. In conclusion, the regular Jjimjil exposure has positive effects upon improvement in regulation of body temperature, blood pressure, and $Na^+$ concentration especially in heat tolerance.

• Plant Breeding and Biotechnology
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• v.5 no.4
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• pp.363-370
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• 2017

In this study, Quercus acutissima seedlings were subjected to drought for 30 days then analyzed to determine their response to water deficit. The growth phenotype, chlorophyll fluorescence response, fresh weight, dry weight, photosynthetic pigment levels, soluble sugar content, and malondialdehyde (MDA) were measured to evaluate the effects of drought on plant growth and physiology. The growth phenotype was observed by infrared (IR) digital thermal imaging after 30 days of drought treatment. The maximum, average, and minimum temperatures of drought-treated plant leaves were $1-2^{\circ}C$ higher than those of the control. In contrast, the fresh and dry weights of the dehydrated leaves were generally lower than those of the control. There were no significant differences between treatments in terms of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid levels. Nevertheless, for the drought treatment, the $F_v/F_m$ and $F_v/F_o$ ratios (chlorophyll fluorescence response) were lower than those for the control. Therefore, photosynthetic activity was lower in the dehydrated plants than the control. The drought-stressed Q. acutissima S0536 had lower soluble sugar (glucose and fructose) and higher MDA levels than the controls. These findings may explain the early growth and physiological responses of Q. acutissima to dehydration and facilitate the selection of drought-resistant tree families.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.11
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• pp.1645-1652
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• 2007

The purpose of this study was to evaluate physiological response and subjective sensation of functional knitwears with different materials and designs. The three different types of knitwears were knitted(polar-neck with cotton/chitosan-C, V-neck with cotton/chitosan-CV and polar neck with cotton/chitosan/silver yarn-CS) and evaluated by four healthy female subjects. Eardrum temperature, mean skin temperature, clothing microclimate, and heart rate were measured in climatic chamber($30^{\circ}C$, 50%RH, 0.5m/sec). The results were as follows. 1. Eardrum temperature was generally evaluated as lower in CV and CS than in C. Mean skin temperature was lower in knitwears with silver yarn than in knitwears without silver yarn. 2. Clothing microclimate temperature on the chest was lower in knitwears with silver yarn than in knitwears without silver yarn. 3. Clothing microclimate humidity was generally lower knitwears with silver yarn than knitwears without silver yarn. 4. Heart rate was lower in knitwears with silver yarn than in knitwears without silver yarn and lower in V-neck than in polar neck. 5. Thermal sensation was slightly warmer in knitwears without silver yarn than in knitwears with silver yarn. Overall comfort sensation was evaluated as more comfortable in CV and CS than in C.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.8
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• pp.1095-1106
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• 2013

This study evaluated the wear comfort properties of water-vapor-permeable (WVP) garments using a movable sweating thermal manikin. Manikin tests were performed in a climatic chamber (temperature T=20, $35{\pm}0.5^{\circ}C$ and relative humidity $H=50{\pm}10%$) using seven sportswear outfits (a long sleeve shirts and a long pants) made with seven different WVP fabrics. Physiological responses of wear trials could be correlated with measurement parameters of the thermal manikin experiment; subsequently, a regression model that represented a final comfort sensation could be obtained. The regression model developed in this work is based on thermal manikin measurements; consequently, it provides an independent comfort sensation level in a relatively short time at a low cost while maintaining the reproducibility of results. It translates into more actual choices for sportswear manufacturers and sportswear consumers.

• Journal of the Ergonomics Society of Korea
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• v.16 no.2
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• pp.39-59
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• 1997

With a view to providing basic data for designing male's and female's clothes, healthy males and females(five each) were exposed to three different environmental temperature($20{\pm}1.0^{\circ}C$, $28{\pm}1.0^{\circ}C$, $32{\pm}1.0^{\circ}C$) in the nude. Their adaptation of skin temperature, physiological responses( rectal temperature, blood pressure, pulse rates) and psychological reactions(thermal, comfort and perceptive sweaty sensations) were analyzed as follows; The subjects's skin temperature had a similar look of adaptation, but the stability of skin temperature differed at tha $20{\pm}1.0^{\circ}C$ and at the $28{\pm}1.0^{\circ}C$ Males had higher skin temperature at three environmental temperatures, but females showed a higher temperature change at the $20{\pm}1.0^{\circ}C$ and $28{\pm}1.0^{\circ}C$ and males at the$32{\pm}1.0^{\circ}C$ Thus females were more resistant to the cold, while males were more resistant to the heat. As environmental temperature increased, rectal temperature and pulse rates also grew up. Females turned higher in rectal temperature and lower in blood pressure, but both sexes had a normal range of physiological reactions. Even though three environmental temperatures were same changes in thermal sensation at $28{\pm}1.0^{\circ}C$and in perceptive sweat sensation at $32{\pm}1.0^{\circ}C$, two sexes had the same response in comfort sensation at the three environmental temperatures.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.12
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• pp.846-851
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• 2012

The radiant floor heating system is traditional heating system in korea. Radiant floor heating is small in vertical temperature difference, air stream and radiant heat distribution is uniform. And radiant floor heating system provide thermal comfort conditions to the a resident. This study was undertaken to evaluate the physiological-subjective responses of the resident's posture change such as sitting and standing. The experimental investigations were carried out in climate chamber, and subjects were 4 college-age students in good health. The physiological response was skin temperature and subjective response was undertaken survey of TSV and CSV. The results were summarized as follows; The comfortable temperature range of plantar surface was $35.1{\sim}38.9^{\circ}C$ and buttock surface was $37.8{\sim}39.3^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.524-529
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• 2007

Pressure inactivation behavior of Bacillus amyloliquefaciens spores was investigated in deionized water. The spores of B. amyloliquefaciens were subjected to $105^{\circ}C$ and 700 MPa. The magnitude of the decrease in viability after pressure treatment was similar to that after pressure treatment followed by heat shock. The increase of dipicolinic acid (DPA) release was correlated with the spore inactivation, and the hydrophobicity did not significantly change during the pressure-assisted thermal processing (PATP). Lag phase duration increased with increasing pressure process time. The mechanisms of spore germination and inactivation during the PATP were related to a complex physiological process.

• Journal of the Korean Society of Industry Convergence
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• v.1 no.1
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• pp.21-30
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• 1998

The purpose of this study is to clarify the floor temperature on the human body and to estimate thermal comfort zone in a heated room. In order to evaluate the effects of floor heating, a series of experiments were carried out using Korean subjects. The following experiments were conducted: 1) to obtain the effective radiation area and configuration factors of the person in the sitting posture on a floor to get the mean radiant temperature, 2) to measure contacted area of the person to the floor to calculate conduction heat rate, 3) to measure convective heat transfer coefficient of the body and 4) to know the thermal comfort zone of indoor environment heated by ON-DOL. Subjects were exposed to the following conditions: combinations of air temperature $20^{\circ}C$, $22.5^{\circ}C$, $25^{\circ}C$, and floor temperature $20^{\circ}C$, $22.5^{\circ}C$, $25^{\circ}C$, $27.5^{\circ}C$, $30^{\circ}C$, $32.5^{\circ}C$, $35^{\circ}C$, $37.5^{\circ}C$, $40^{\circ}C$ under still air and 50% relative humidity in the controllable artificial climate chamber. To evaluate the effect of heat conduction between the body and a floor modified mean skin temperature was defined. Weighting coefficient to calculate mean skin temperature were modified with the contacted area. The experiments revealed a positive correlation between the modified operative temperature and the modified mean skin temperature. The modified mean skin temperature can indicate the effect of heat conduction between body and a floor surface.

• The Korean Journal of Community Living Science
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• v.24 no.4
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• pp.543-552
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• 2013

Physiological and subjective responses of the farmers and thermal environment during chili harvest in the open field were investigated to evaluate the thermal environments and farmers's workload. Eight career female farmers in their sixties participated as subjects both in morning work(MW, AM 9:00~10:30) and in afternoon work(AW, PM 15:00~16:30) with each lasting about 90 minutes. The results were as follows. 1) Air temperature, air humidity, globe temperature and WBGT of MW were mean $25.54^{\circ}C$, 81.82%RH, $37.72^{\circ}C$, $26.27^{\circ}C$ and AW were mean $30.63^{\circ}C$ 82.50%RH, $40.11^{\circ}C$, $30.02^{\circ}C$, respectively. By the WBGT, we evaluated that the thermal environment in the afternoon in the open field gave a thermal burden to farmers. 2) Mean skin temperature of AW($34.8{\pm}0.8^{\circ}C$) was higher than MW($33.5{\pm}1.2^{\circ}C$)(p<0.05). Clothing microclimate temperature on the chest of each work time were $31.3^{\circ}C$(MW) and $32.7^{\circ}C$(AW). Clothing microclimate humidity on the chest of each work time were over 80%RH. Heart rate were 88.5bpm(MW) and 91.7bpm(AW) respectively. 3) Farmers working in the afternoon felt uncomfortable after 45~60 min. of work and in the morning they felt uncomfortable after 90 min. of work. We evaluated that the harvesting of chilies in the open field was 'moderate work' by the physiological responses but the level of thermal burden increased over time especially in the afternoon work. It is suggested that farm workers should drink fluids between work to stay in homeostasis by sweating and to take frequent rests. Active clothing ventilation and wearing functional garments would help farm workers excrete sweat effectively.

• The Research Journal of the Costume Culture
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• v.12 no.2
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• pp.279-289
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• 2004

This study was conducted to compare the hunting reaction of finger in the cold water. Finger skin temperature is measured the left middle finger tip immersion in cold water of 5℃ for 30 minutes and measurements were made on finger skin temperature(Ts), thermal comfort, and cold pain sensations during the experiment at the spring (March) and Winter(December). Results were follows. Is before immersion was at the highest in spring and at the lowest in winter and was closely related to the indoor temperature Ts during immersion and recovery. Mean of finger skin temperature(MST), the skin temperature at the first rise(TTR) and amplitude of finger skin temperature reaction during immersion(AT) were significant higher in spring than that in winter(P＜.01). The lowest skin temperature(LST) during the cold water immersion were significantly higher in spring than that in winter (P＜.05). The frequency of the appearance of cold-Induced vase dilation(CIVD) was higher in spring than that in winter. However, time for the first temperature(TTR) and recovery time(RT) had no seasonal variation. In addition, cold pains during immersion were felt more strongly in spring than in winter. Local thermal sensation, finger thermal sensation in dynamic state during hand immersion was different from that in the Winter. Spring was slowly cold in cold water immersion.