• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.261-266
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• 2015

This study was conducted to examine the effect of tree density of Pinus koraiensis forest on the thermal comfort and the physiological response of human body in summer season. As the indicators of thermal comfort were used the predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD), while the heart rate variability was used for the physiological indicator of subjects. The subjects were 15 physically healthy men and women in their 20s ($23.7{\pm}1.7$ years old). The subjects sat in each site to measure HRV for 5 minutes and the thermal comfort of each site was measured. As a results, it was proven by PMV and PPD that the Pinus koraiensis forest with 120% tree density was thermally more comfortable than the Pinus koraiensis forest with 80% tree density. In case of the subjects' physiological response, the Pinus koraiensis forest with 120% tree density showed significantly higher HF of HRV than the Pinus koraiensis forest with 80% tree density and significantly lower LF/HF. Therefore, the findings of this study scientifically proved that the Pinus koraiensis forest with 120% tree density is thermally more comfortable and physiologically more relaxing than the Pinus koraiensis forest with 80% tree density.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.24-31
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• 2015

The purpose of this study is to provide the thermal comfort range according to the residential style and clothing level at radiant floor heating space, and compare the annual energy consumption and energy cost for each condition. Lower neutral point temperature has been stood for floor sitting style than chair sitting style, which appears that the thermal sensation was affected by local heat transfer between floor surface and the human body. The result of research indicates that neutral point temperature was in inverse proportion with the clothing level. It is interpreted that the increasing of clothing level results decrement of heat loss from human body, and is available to achieve same thermal comfort at lower room temperature. It was analyzed that the floor sitting style is more economical residential style than the chair sitting style, because the energy consumption of the floor sitting style is saved by 6.0% in average to compare with that of the chair sitting style. It is analyzed that energy consumption has been decreased by 13.5% with the clothing level of 1.2 Clo than with that of 1.0 Clo, and decreased by 18.0% than with that of 0.8 Clo, which explains that the energy saving can be achieved with the variation in life habit to increase the clothing level.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.544-553
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• 2023

The purpose of this study was to reveal the thermal comfort and physiological and psychological effects of spending time in broad-leaved forests in suumer. Thirty-one university students (with an average age of 21.4 ± 2.1 years) participated in the study, and a within-subjects experimental design methodology was used. The participants moved to an experimental site (with a crown closure of 76.6%) or a control site (25.9%), sat on a chair to eliminate the impact of movement, and rested for 5 minutes with closed eyes. At this time, thermal comfort, heart rate variability, heart rate, and forehead temperature were continuously measured. After that, blood pressure and pulse rate were measured, and a subjective evaluation was conducted. As a result, spending time at an experimental site showed a statistically significant decrease in the predicted mean vote and the percentage of dissatisfied values, enhancement of parasympathetic nerve activity, decrease of forehead temperature, diastolic blood pressure, heart rate, pulse rate, and improvement of personal thermal sensation (thermal sensation vote and comfort sensation vote). In conclusion, it was found that a forest with high crown closure reduces thermal stress and induces physiological and psychological relaxation.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1020-1031
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• 1998

This study was done to investigate thermal reponses and to obtain the basic information of thermal comfort by sex and posture under the Ondol heating system. Six healthy males and females were exposed to Ondol(Room Temp.: 25$\pm$1$^{\circ}C$, 50$\pm$10%R.H, Floor Temp.:30$\pm$1$^{\circ}C$) on the of posture such as sitting, lying aside and supine on the floor for 30 minutes after 30 minutes' control phase. During the experiment, rectal temperature, skin temperature of 10 areas, local sweating rate, clothing microclimate, subjective sensation were measured. Rectal temperature gradually decreased and mean skin temperature grad-ually increased both male and female in any posture. There was not significant difference between male and female in rectal temperature and mean skin temperature. There were significant difference among the postures in rectal temperature(p<0.001) and mean skin temperature(p<0.001). In lying aside and supine on the floor, appearances of change and changes in rectal temperature and mean skin temperature were large, changes of weight were small. In sitting on the floor, appearances of change and changes in rectal temperature and mean skin temperature were small, changes of weight were large. The trunk skin tem-perature was higher in female than in male, but the extremity skin temperature was higher in male than in female. In sitting on the floor, foot skin temperature(p<0.001) was higher than any other local skin temperature. In supine on the floor, back skin temperature(p<0.001) was higher than any other local skin temperature.

• Science of Emotion and Sensibility
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• v.25 no.4
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• pp.95-106
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• 2022

This study evaluated the effects of latex mattresses on sleep quality and comfort. The participants were 11 healthy adults (five males, six females, mean age 37.7 years, mean height 167.8 cm, and mean weight 67.0 kg) without severe insomnia or other disease that could affect sleep, examined by a clinician. In their personal living space, participants slept on a spring mattress for 7 days, with their sleep registered using a wearable device (Fitbit), a sleep log, the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and a satisfaction survey. The mattresses were then replaced with latex mattresses, which were used for 14 days. As a result, sleep time increased by 62.9 min on weekdays and 53.2 min on weekends after using the latex mattress, and a significant decrease, of 3.8, as seen on the ISI. As measured by the PSQI, the poor sleepers decreased from 10 to 7, but this was not statistically significant, and in the satisfaction survey, the comfort of the low back, neck, and shoulders was significantly increased. This suggests that changes to latex mattresses may positively affect objective and subjective sleep quality.

• Journal of the Ergonomics Society of Korea
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• v.24 no.4
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• pp.55-62
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• 2005

This study examined the effect of ergonomic heel rest that was designed for drivers who have physical handicap in the low leg muscles or have to drive prolonged hours with frequent foot pedaling. An experiment was designed to test the ergonomic heel rest with traditional foot pedal. Forty subjects participated in the experiment. Electromyography(EMG) was used to monitor the muscle activity and fatigue of right leg, and Electro-goniometer was used to measure the ranges of motions of the knee and ankle. A simulator of driver's seat was built for the experiment and the heel rest was installed on it. In order to examine the low muscle activity and range of motion, subjects used the foot pedal for 15 minutes repetitively for each experimental condition. Another 15 minutes test without the heel rest was also performed for comparison. The Root Mean Square(RMS) and Mean Power Frequency(MPF) Shift were used to quantify the level of muscle activity and local muscle fatigue. In results, statistically significant decreases of muscle activity and fatigue were found in all the low leg muscles. The range of motion of the knee and ankle joint also decreased when the heel rest was used. The mechanism of the heel rest effect was discussed in this study. This type of heel rest can be applied to real driving situation after ensuring the safety, or overcoming the psychological discomfort possibly due to unfamiliarity.

• Research in Community and Public Health Nursing
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• v.18 no.3
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• pp.400-409
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• 2007

Purpose: This study was performed to investigate the level of subjective health status, religiosity and the fear of death of the elderly and to identify the relationships among them. Methods: This study was a cross-sectional descriptive study using a questionnaire. Fear of Death Scale that was made by Loo & Shea (1996) and translated and revised by Kim(2003) was used to measure the fear of death. The data was analyzed using SPSS. Results: The subject was 128 community dwelling elders who had a religion. Of the respondents, 50% felt 'not healthy', and 69.5% was moderately religious. The mean score of FODS was 3.18 (out of 5). The mean score of each subcategory of FODS was as follows: Death anxiety about the death of self was 3.00. Death anxiety about the dying of self was 3.18. Death anxiety about the death of others was 3.31 and death anxiety about the dying of others was 3.23. There was a statistically significance correlation between the level of religiosity and FODS (F=3.29, p= .040). Conclusion: Health professionals may make efforts to learn about healthy attitudes toward death and aid for the elderly and to comfort them. Death education programs are needed for the elderly.

• Women's Health Nursing
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• v.4 no.3
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• pp.297-308
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• 1998

The purpose of this study was to define whether NSILQ is useful for the nursing student in supporting women labor room(Nursing Support in Labor Questionnaire). The retrospective study was conducted to identify the helpfulness of nursing student support behaviors as perceived by women in Labor. This sample of 152 women completed two data collection instruments : a demographic & obstetric questionnaire(12) and NSILQ(20). The data were analyzed by Cronbach alpha, descriptive statistics, t-test, ANOVA with SAS program. The result of this study are as follows. 1. All of NSILQ nursing behaviors were perceived as helpful in this study. The total mean of perceived score was $3.4{\pm}0.90$. 2. According to the type of nursing support, the mean of Affect(AT) care was $3.48{\pm}0.79$, the mean of Aid(AD) care was $3.37{\pm}0.82$, the mean of Affirmation(AM) care was $3.35{\pm}0.90$. Among the type of care, the AD care was 52.2%, and the most helpful one. 3. The significant characters of nursing support are antenatal care numbers and husband with or not in labor process. In the group of score of nursing support, the number of antenatal care was low(F=3.90, P=0.02). The score of the group husbands in labor process was higher.(T=4.55, P=0.001). 4. The significant characters of influencing on nursing support required are the person who helped and whether women has job or not. 5. The highest numbers of wanting nursing support are Aid cares(74.3%). The care the women wanted mostly was Aid cares (74.3%; pain control in labor(56.6%), physical comfort(6.6%), coach in labor(3.9%), explain of dilatation(1.3%) in rank.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.6
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• pp.1003-1009
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• 1997

To study the time course of increased cold tolerance, the physiological responses were measured during the course of a 2-yr study (Feb. 1995~Feb. 1996) of four female college students, whose cold tolerance was proved to be increased through wearing cool clothing in daily life from Sep. 1994 to Feb. 1995. To determine their cold tolerance, subjects rested at 25$\pm$1$^{\circ}C$, then were exposed to 15$\pm$1$^{\circ}C$, 50$\pm$5% R.H. for 90min in Feb. 1995 and Feb. 1996. Subjects' rectal temperatures, mean skin temperatures, heat production, shivering onset, thermal sensations, and comfort showed no significant changes, when they were measured in 1995 and 1996. Based on these results, we can safely assume that mild cold acclimatization coming from wearing cool clothing lasts at least oneyear, that is until the following year. One of the possible explanations for this is that the subjects did not increase their clothing thermalresistances after the cold acclimatization.

• Journal of National Security and Military Science
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• s.1
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• pp.231-247
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• 2003

To get the basic data for making comfortable military uniforms and to examine the distribution of clothing microclimate, seasonal fluctuations of skin temperature, subjective sensation, and clothing microclimate were measured from 10 males. The subject were questioned on thermal comfort in experiment. Clothing microclimate temperature at breast, skin temperature at four sites (breast, upper arm, thigh, leg), deep body temperature at eardrum( tympanic temperature), and subjective sensation were measured for an hour in the controlled climatic chamber. The subjects felt comfortable when skin temperature were recorded $34.43^{\circ}C$ at breast, $33.53^{\circ}C$ at upper arm, $32.9^{\circ}C$ at thigh, and 32.50 at leg. Then mean skin temperature was $33.55\pm$$0.63^{\circ}C$. Clothing microclimate temperature ranged from 31.2 to $33.8^{\circ}C$, and clothing microclimate humidity ranged from 49.80～52.41%. In the comparison of these results with the microclimate of military uniforms, it needs more insulation in clothing for military uniforms. It also says that military uniforms should be made of the textiles which can control humidity.