• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.9
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• pp.979-988
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• 2014

Recently, the interest in the thermal comfort is ever increasing as the time people stay in the automobile is gradually increasing. So far, however, the cooling performance of the HVAC(heating and ventilation air conditioning) system is evaluated by thermal environment criteria such as indoor air velocity and temperature, not by a thermal comfort index. Furthermore, the precise criteria has not been established yet when the thermal comfort for the automobile is evaluated using numerical analysis. In this study, the numerical analysis of automobile indoor thermal comfort according to various parameters such as HVAC operating mode, airflow, passenger boarding conditions is performed during the HVAC system's initial operating time(20 minutes). The solar ray tracing model and S2S radiation model are used and validated to simulate an external heat source. Based on this study, an evaluation model which can predict the thermal comfort index for the combination of the above parameters is presented.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.97-101
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• 2009

Calculating and predicting the thermal comfort in outdoor environment are difficult than in indoor environment because composition parameters are variable, interrelations among parameters are very complex and human activities in outdoor are diverse. Moreover, the thermal expectancy of subject in outdoor environment is different from that of indoor environment. The aims of this study are to examine the difference between indoor and outdoor thermal comfort range. With this in mind, field measurement for estimating outdoor thermal environment and a questionnaire survey with simultaneous measurement around the subject were conducted.

• Journal of the Korean Society of Industry Convergence
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• v.1 no.2
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• pp.65-74
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• 1998

The purpose of this paper is to investigate the mount of relief of human solar heat load and thermal comfort in outdoor environment in summer, Six different types of sites, T garden and its neighboring area in Japan, were selected as the experiment sites. The experiments were conducted from 22 to 29 August, 1994 to find the relationship between climatic conditions and human responses, Climatic conditions, subjects's thermal sensation and skin temperature were measured. Radiant heat exchange on the human body was estimated on the basis of the measured air and surface temperature and solar radiation. Thermal index Operative Temperature and New Effective Temperature was modified with the effect of the radiant heat exchange. Human thermal comfort and skin temperature is affected by the solar radiation and the sky factor in an outdoor environment. The effect of tree shade was verified on thermal comfort, The mount of relief of human solar heat load is relation to the existence of shade a solar radiation and the sky factor. The urban garden is one of the effective design element in an urban environmental planning.

• Proceedings of the ESK Conference
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• 1998.04a
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• pp.188-193
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• 1998

The purpose of the study is to develop a numerical model based on experimental data to estimate the thermal comfort in the driving room of a motorcar. For the ecperiments, three air temperature level of 21, 23, 25 .deg. C are set to measure variable such as average skin temperature, R-R interval, the comfort sensation, and the performance level. By performing statistical analysis with the results obtainted, it is observed that two physiological factors-average skin temperature and R-R interval have significant relation with the thermal comfort in the driving room. Thus, those two factors are included as parameters in the proposed model to estimate the thermal comfort.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.1
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• pp.5-11
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• 2006

This study was performed to determine the effect of structural characteristics of selected wool fabrics on mechanical and thermal properties. 52 wool fabrics, including 18 plain woven fabrics and 34 twill and satin woven fabrics were used as samples woven with various weft density for the study. Several physical characteristics such as mechanical properties, keeping warmth ratio of wool fabrics were measured. Data analyses including 1) analysis of tactile and thermal comfort sensation were performed. the following were obtained from the results: The main factors affecting keeping warmth ratio were thickness and bulk density. The keeping warmth ratio of samples increased with increasing thickness and decreasing bulk density of samples. In addition, coefficient of friction of the samples increased with keeping warmth ratio of samples. The above results show that wearing sensation and comfort properties of fabrics are changed depending on the end-use, and thus, above results can be used to manufacture of fabrics for specific end-use with high comfort properties.

• The International Journal of Costume Culture
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• v.3 no.1
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• pp.30-40
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• 2000

The purpose of this research was to device thermal comfort model for radiation power plant workers in protective clothing. Three fabrics commonly used in protective workwear were made into coveralls of identical design and were evaluated by adult healthy males in four simulated work environment. It was investigated between the physiological response and subjects comfort according to environmental variance and clothing types. The of simulated work enviro mensent was controlled under four different humidity and temperature of each type. (Temperature 20±1℃, RH 40∼70%±5%, Temperature 30±1℃, RH 40∼70%±5%) An index of physiological response was connected with the thermal comfort designed. Mean skin temperature, skim temperature, Axillasy temperature ear canal temperature, clothing climate, total sweat, blood pressure, and R-R interval were be evaluated. Skin temperature difference ocurring during exercise and rest were significant only with respect to time and regions of the body, This despite physical differences in the three coveralls, particulary mass statistically experiment. Also, an index of subject wearing sensation was designed for thermal comfort after investigation determined the kind of clothes and the type of environment. As a result of this research, two types of multiple regressions was deviced to estimate thermal comfort of the protective clothing.

• Journal of the Korean Home Economics Association
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• v.30 no.2
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• pp.81-86
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• 1992

The purpose of this study was to investigate the psychophysical correponding to temperature and to establish the comfort zone of thermal environment for Korean in winter. An experimental investigation was carried out in climate chamber maintaining the air temperature at 20, 22, 24, 26℃ and subjects were 128 college-age Korean(64 males and 64 females) in good health. Data were analyzed by SPSS PC＋ packages. 'Neutral' on the thermal sensation ratings was most frequently indicated at 24℃ by subjects was 23.1℃ (male 24.0℃, female 22.7℃), therefore the comfort zone of thermal environment in winter was considered as 23∼24℃.

• Journal of Biosystems Engineering
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• v.34 no.1
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• pp.1-7
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• 2009

In order to evaluate environmental comfort of tractor cabs, temperature, relative humidity and noise within the cab were taken from 31 tractors during plowing and rotovating operations. The temperature and humidity were evaluated with regard to the comfort zone of KS B ISO 14269-2 and PMV of ISO 7730. The noise was evaluated with regard to the permissible sound level of OSHA for daily exposure of 8 hours. The collected data indicated that thermal environment of the cabs was out of the comfort zone, which meant tractor operators worked under uncomfortable thermal conditions. Difference in the thermal comfort by tractor power and maker, and type of works was not found. However, 25% of the studied tractors showed PMV in a range of -0.5 to +0.5, which indicated their operators worked under the comfort criteria. PMV was improved when the cab was air-conditioned. Levels of measured cab noise were lower than the permissible criteria, and 76.7% of the studied tractors had cab noise ranged from 75 to 85 dBA. There was a tendency that high powered tractors, rotovating operations and locally-made tractors had greater cab noise levels. However, their differences were insignificant.

• Journal of Sensor Science and Technology
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• v.12 no.1
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• pp.24-33
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• 2003

This research is about a comfort sensing system for human environmental monitoring using a one-bodied humidity and temperature sensor and an air flow sensor. The thermal comfort that a human being feels in indoor environment has been known to be influenced mostly by six parameters, i.e. air temperature, radiation, air flow, humidity, activity level and clothing thermal resistance. Considering an environmental monitoring, we have designed and fabricated a one-bodied humidity and temperature sensor and an air flow sensor that detect air relative humidity, temperature and air flow in human environment using surface micromachining technologies. Micro-controller calculates a PMV (predicted mean vote) and CSV (comfort sensing vote) with sensing signals and display a PMV on LCD (liquid crystal display) for human comfort on indoor climate. Our work has demonstrated that a comfort sensing system can provide an effective means of measuring and monitoring the indoor comfort sensing index of a human being. Experimental results with simulated environment clearly suggest that our comfort sensing system can be used in many applications such as air conditioning system, feedback controlling in automobile, home and hospital etc..

• 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.