• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.515-521
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• 2004

The Purpose of this study was to investigate the effect of body fat on thermophysiological responses and subjective sensations under hot environment. Fifteen female college students volunteered as subjects. Subjects were organized into three groups - low body fat group(L group : less than 20% of body fat), medium body fat group(M group : 20%~30% of body fat) and high body fat group(H group : More than 30% of Body fat). The experiment was carried out in a climate chamber of $32^{\circ}C$, 60%RH with the repeat of having 'Exercise' and 'Rest' period. The results of this study are as follows ; Rectal temperature maintained higher in M group and L group than in H group in the period of exercise 1. High body fat was so effective in keeping the core temperature, it seems that as was usually the case in cold environment. The mean skin temperature was the lowest value in H group but the ratio of mean skin temperature change was clearly high value in H group. The above facts indicated that thermophysiological response occurs rapidly in H group. Blood pressure, pulse rate and metabolic rate of H group showed the highest values and those of L group showed the lowest value in all period of experiment. Effective of sweating rate was higher in H group than other groups. In subjective sensations, The H group felt more pleasant and comfortable than M group. With these results in mind, people of H group responses more actively for thermal regulation in a hot environment, and these leads H group to feel more pleasant and comfortable.

• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.39-45
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• 1995

Temperatures of blood and skin, respiratory rate and plasma cortisol concentration in sheep at a warm (average ambient temperature of $15.3^{\circ}C$) and a hot (average ambient temperature of $27.0^{\circ}C$ environment were measured to investigate the effect of hot environment on the physiological responses in ruminant. Temperatures of core, mean skin and mean body in sheep were tended to increase at day time and to decrease at night time at both warm and hot environment, while 24-hr average for those temperatures were significantly higher at hot environment than at warm environment (P<0.05). The calculated body heat content was higher in sheep at hot environment than at warm environment (P<0.05). Respiratory rate and plasma cortisol concentration had no significant differences between warm and hot environment, suggesting that sheep were not stress by the hot environment in this experiment. It is, therefore, suggested that sheep were well adopted to hot environment by increasing body heat content against heat stress.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.4
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• pp.321-327
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• 2002

There has been an increase in the public concern about possible health risks by electromagnetic exposure from mobile phones. Recently, increase in the use among young children of portable telephones public concern regarding potential health hazards due to a hot spot appearing inside the infant head, has been growing. Since the biological hazards due to RF exposure are caused mainly by a temperature-rise in tissue, the effect of localized SAR for portable telephones should also be related to the temperature-rise in the human head. In this paper, it was measured that in the actual use of portable telephone the temperature of the local tissue in the human-head change. As a result, it should be noted that the mean temperature of human-body and localized tissue is rising from beginning call. However the temperature variation of localized tissue is recovered rapidly as normal temperature, although the mean temperature of human-body rising continuously at ending call of portable telephone.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.315-320
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• 2005

With regard to the fact that temperature of human body remains almost constant at $37^{\circ}C$, changes by circadian variation, this study intended to investigate the effect of circadian rhythm on physiological responses of human body according to body fat rate. Fifteen healthy adult women were recruited for this study and were measured body fat as a method of bio impedance. We organized subjects into three groups ; low body fat group(group L-less than 20% of body fat), medium body fat group(group M-20%~30% of body fat) and high body fat group(group H-more than 30% of body fat). The experiment was carried out in a climate chamber of $32^{\circ}C$, 60% RH with the repeat of 'Exercise' and 'Rest' period. Subjects participated in two experiments, one is morning experiment(called 'AM'), the other is afternoon experiment (called 'PM'). The results of this study are as follows ; As to the variation of rectal temperature, group L and M had a significant difference in the time of the day between AM and PM, but group H had almost the same rectal temperature in the two kinds of experimental time. The reason why group H had a smaller difference in the circadian rhythm of rectal temperature in this study is estimated at the Budd et al.(1991)'s results that body fat had effects on reduction in thermogenesis, radiation, mean skin temperature, and increase in insulation of the tissues. Group M had the highest mean skin temperature in the 'PM'. All the 3 groups didn't have stable values in 'AM'. But it showed more stable in 'PM' than 'AM'. Sweat rate was the highest in group H in both 'AM' and 'PM'. Group M had larger sweat rate in 'PM' than 'AM'. but in group L and H, sweat rate was almost the same in two kinds of time of the day. This result suggests that who have more or less body fat have larger difference in sweat rate between morning and afternoon than who have normal body fat.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.179-182
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• 1994

A study was conducted using four dairy heifers to determine the effect of 10, 20 and $30^{\circ}C$ environmental temperatures on the physiological responses and heat production, at a fixed level of TDN intake ($60.5\;g/kg^{0.75}\;d$). The analysis showed significant affects of environmental temperature on respiration rate (RR), mean body temperature (Tb), changes in body heat storage (S) and heat production (HP). The HP at $20^{\circ}C$ was almost the same as at $10^{\circ}C$, but the HP at $30^{\circ}C$ was 11% higher than at $10^{\circ}C$. A tendency for an elongation of standing time (ST) with the increase in environmental temperature was also observed. These results suggest that the increase in energy cost of elongation of ST ($9.2\;kJ/kg^{0.75}\;d$) and $1.3^{\circ}C$ increase in Tb ($17.3\;kJ/kg^{0.75}\;d$).

• Fashion & Textile Research Journal
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• v.22 no.2
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• pp.250-260
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• 2020

The purpose of the present study was to explore the most effective body region and cooling temperature to alleviate heat strain of workers in hot environments. We developed liquid cooling hood, vest, sleeves and socks and applied the water temperatures of 10, 15, 20, and 25℃ through the liquid cooling garments in a hot and humid environment (33℃ air temperature and 70% RH air humidity). A healthy young male participated in a total of 16 experimental trials (four cooling garments × four cooling temperatures) with the following protocol: 10-min rest, 40-min exercise on a treadmill and 10-min recovery. The results showed that rectal temperature, mean skin temperature, and ratings of perceived exertion during exercise; heart rate and diastolic blood pressure during recovery; and total sweat rate were lower for the vest condition than other garment conditions(p < .05). However, there was no differences in mean skin temperature among the four cooling garments when we compared the values converted by covering area(%BSA). When we classified the results by cooling temperature, there were no consistent differences in thermoregulatory and cardiovascular responses among the four temperatures, but 25℃ water temperature was evaluated as being the most ineffective cooling temperature in terms of subjective responses. In conclusion, the results indicated that wearing cooling vest with < 20℃ cooling temperature can alleviate heat strain of workers in hot and humid environments. If the peripheral body regions are cooled with liquid cooling garments, larger cooling area with lower cooling temperature than 10℃ would be effective to reduce heat strain of workers. Further studies with a vaild number of subjects are required.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.287-293
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• 2008

The purpose of this study was to clarify the effects of air and ceiling temperatures on a type of ceiling cooling system that involves cool water circulation. The experiment is conducted in summer. The subjects (11 young females) are exposed to the following conditions: combinations of air temperatures $(27^{\circ}C,\;29^{\circ}C,\;31^{\circ}C)$ and ceiling temperature of $(22.7^{\circ}C,\;23.7^{\circ}C,\;24.7^{\circ}C)$ in still air and RH 50%. The following results were obtained; the thermal sensation vote is neutral at a mean skin temperature of $34.5^{\circ}C$. The ceiling temperature affected different parts of the body. For example, the forehead, scapula and abdomen produced different skin temperatures. Thermal comfort vote was rated as comfortable at high temperature environment. The satisfaction from the ceiling temperature was valued comfortable zone in this experiment. Mean skin temperature showing higher thermal neutrality temperature than existing studies for floor and wall radiation cooling results.

• Journal of the Korean housing association
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• v.7 no.2
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• pp.121-129
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• 1996

This study was to estimate how about various effects on the body thermal sensation as air velocity. clo. mean radiant temperature and resultant temperature are varied. The indoor thermal environment elements are measured under the five different of air velocity. Using the above considerations. the following results are obtained. ▶ The states, the air velocity under 0.5 m/s and 0.63 to 0.9 clo. were shown that the comfort zone of mean radiant temperature by 21.2~24.7C, the neutral point by 22.8C, the resultant temperature by 20.7-24.4C and the neutral point by 22.6C. ▶ On equal condition, the draft was occurred at a given air-velocity under 0.5m.s. It was also appeared the floor panel heating system affecting the body thermal sensation by the subject’s below-chest parts and the local discomfort by sensations on the feet and the knees.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.4 no.2
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• pp.351-358
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• 1997

Body temperature should be measured accurately to assess neonate's condition for proper care. Temperatures measured in rectal, axillary and tympanic site were compared in 129 normal neonates to find out proper nursing time for measuring temperature and the validity of fever detection. The results were as follows : 1. Mean temperatures of axillary and tympanic site($36.85^{\circ}C,\;37.12^{\circ}C$) were significantly lower than those of rectal site($37.19^{\circ}C$). 2. Mean nursing time for measuring body temperature was significantly higher and lower in axillary and tympanic temperatures(159.49 seconds, 11.07 seconds) than in rectal temperature(105.62 seconds). 3. Tympanic and axillary temperatures were significantly correlated with rectal temperature (r=0.85, r=0.78) and the significant correlation was demonstrated between tympanic and axillary temperatures(r=0.76). 4. Sensitivity, specificity, positive and negative predictive values were 0.87, 0.90, 0.72, 0.96 for detecting fever respectively. The above findings indicated that the tympanic thermometer offers a useful alternative to conventional methods.

• The Korean Journal of Community Living Science
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• v.22 no.3
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• pp.485-491
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• 2011

This study was to present the preferred and the suggested indoor temperature of college students in winter based on their body composition. A total of 14 subjects(6 males and 8 females) participated in this study. They sat in a climatic chamber controlled at $24^{\circ}C$ wearing experimental garments(0.7clo). The air temperature decreased $1^{\circ}C$ every 15 minutes until it reached $19^{\circ}C$. After the stepwise temperature change, subjects were asked to select a comfortable air temperature by dialing the temperature control switch inside the chamber. The preferred temperature was determined when subjects did not change the air temperature for 10 minutes. The measurements were oxygen consumption, rectal temperature, skin temperature, and subjective sensation. Main results are as follows. In a mild cold condition, females demonstrated lower oxygen consumption and mean skin temperature than males while keeping a constant rectal temperature. Females increased rectal temperature and decreased mean skin temperature greater than males from $24^{\circ}C$ to $19^{\circ}C$. Males showed larger oxygen consumption increase than females. It appears that the thermo-physiological responses in a mild cold condition might be different between males and females. The preferred winter indoor temperature was $22.3^{\circ}C$ for males and $23.4^{\circ}C$ for females, and the suggested temperature was $21^{\circ}C$ for males and $23^{\circ}C$ for females.