• Journal of the Korean Society of Clothing and Textiles
• /
• v.7 no.1
• /
• pp.37-43
• /
• 1983

The objective of the study is to obtain the basic data to establish the standard value of proper clothing weights in the change of thermal environment. For the purpose of this research, clothing weight and thermal sensation have been collected from 160 college student in Seoul and Kwangju area in April, July, October. Results are as follows : 1. Subjects were in Comfortable condition, particularly in Spring and Autumn. But in summer they were in warm condition and the case were reversed in winter when they were under cool condition. 2. The frequency of comfortable thermal sensation were low below 16.5 degree, above 27.5 degree, and were high between 16.5 degree and 23 degree on room temperature. 3. Generally, the positive correlation were found between clothing weights and thermal sensation. 4. Clothing weights and thermal comfort were as follows. Season : Spring, Autumn, Room Temperature(${\circ}C$) : 16.3$\~$23, Clothing Weights($g/m^2$) : 589.9$\~$750.6, Season : Summer Room Temperature(${\circ}C$) : 27$\~$32, Clothing Weights($g/m^2$) : 362.4$\~$432.5, Season : Winter, Room Temperature(${\circ}C$) : 12.5$\~$19.3, Clothing Weights($g/m^2$) : 913.7$\~$1206.2

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.2 no.1
• /
• pp.13-22
• /
• 2004

This study presents the thermal analyses of a spent fuel dry storage cask under normal and off-normal conditions. The environmental temperature is assumed to be 15 $^{\circ}C$ under the normal condition. The off-normal condition has an environmental temperature of 38 $^{\circ}C$. An additional off-normal condition is considered as a partial blockage of the air inlet ducts. Two of the four air inlet ducts are assumed to be completely blocked. The significant thermal design feature of the storage cask is the air flow path used to remove the decay heat from the spent fuel. Natural circulation of the air inside the cask allows the concrete and fuel cladding temperatures to be maintained below the allowable values. The finite volume computational fluid dynamics code FLUENT was used for the thermal analysis. The maximum temperatures of the fuel rod and concrete overpack were lower than the allowable values under the normal and off-normal conditions.

• Fashion & Textile Research Journal
• /
• v.14 no.4
• /
• pp.660-668
• /
• 2012

The purpose of this study is to analyze the thermal characteristics of garments marketed for Korean males and to investigate the influence of each garment on ensemble, by measuring their insulation values(clo) using thermal manikins. The results are as follows. The total insulations(clo) of ensembles for S/S seasons are between 1.46 and 2.6 clo, with the mean of 2.12 clo. The insulation in the still air condition is 1.23 clo, which means a decrease of 42% compared to the total insulation of all the component garments. The insulation of ensembles for S/S seasons in the dynamic air condition decreased by 46.8%, compared to the still air condition. The total insulation(clo) of ensembles for F/W seasons is between 3.84 and 7.36 clo with the mean of 4.74 clo. The insulation in the still air condition is 2.26 clo, which means a decrease of 53.6% compared to the total insulation of all the component garments. The insulation of ensembles for F/W seasons in the dynamic air condition decreased by 36.2%, compared to the still air condition. As the clo value of each component garment gets higher, the insulation of ensembles gets higher. Especially, the insulation of ensembles was more influenced by outer wear than inner wear. The insulation of ensembles could be predicted by the insulation of outerwear better.

• Journal of the Korea Concrete Institute
• /
• v.13 no.4
• /
• pp.305-313
• /
• 2001

Conductivity is an important thermal property which governs heat transfer in a solid medium. Generally, the determination of conductivity in concrete is very difficult, because concrete is a heterogeneous material composed of cement, water, aggregate, et cetera and time dependent material of which properties change with curing age. In this study, influencing factors on thermal conductivity of concrete are quantitatively investigated by QTM-D3, a conductivity tester developed in Japan. Then, a prediction equation of thermal conductivity of concrete is suggested from the regression analysis of test results. To consider the factors influencing thermal conductivity of concrete, mortar, and cement paste, seven testing variables (age, amount of cement, types of admixtures, amount of coarse aggregate, fine aggregate ratio, temperature, and humidity condition) of the specimens are used. According to the experimental results, the amount of coarse aggregate and humidity condition of specimen are the main factors affecting the conductivity of concrete. Meanwhile, the conductivity of mortar and cement paste is strongly affected by the amount of cement and types of admixtures. However, the curing age has minor effect on the conductivity variation. Finally, the prediction formula of concrete conductivity as a function of aggregate amount, fine aggregate ratio, specimen temperature, and humidity condition is developed.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.963-970
• /
• 2010

In this study, a series of thermal numerical analysis was conducted through the ground condition and the length and shape of the energy pile. In order to investigate the effect of the thermal properties of ground condition, grout and pile type on heat transfer efficiency in the U-type heat exchanger in energy pile, thermal numerical analysis was done by using ABAQUS. ABAQUS, a finite element analyzing program, was employed to evaluate the temperature distribution on the cross section of energy pile system incorporating HDPE - grout - pile - Ground condition which consists of clay, sand, rock type soil and ground water.

• Journal of Advanced Marine Engineering and Technology
• /
• v.28 no.7
• /
• pp.1145-1151
• /
• 2004

The experiment of thermal performance about cross flow type cooling tower was conducted in this study. Generally the ambient air condition can affect the thermal performance of cooling tower to improve or not. However it is hard to control the cooling water temperature that we want under bad air condition or during rainy season. In this paper, the effect of variables, which the ambient air have. especially wet-bulb temperature, are experimentally investigated for controlling the cooling water temperature more successfully. The result is that there is appropriate air flow rate in respective air condition to preserve the cooling performance in the cooling tower and the maximum air flow rate can't overcome the approach under bad air condition.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2003.10a
• /
• pp.41-46
• /
• 2003

The important problem in high speed spindles is to reduce and minimize the thermal effect by motor and bail bearings. Thermal characteristics according to the bearing pre-load and cooling condition are studied for the test spindl with grease lubrication and high frequency motor. Bearing and motor we main heat generation, and heat generation by ball bearings as a function of load, viscosity and gyroscopic moment effect are considered. Temperature distribution and thermal displacement according to the speed of spindle are measured by thermocouple and gap sensor. The results show that the fitting pre-load and cooling temperature are very effective to minimize the thermal effect by motor an ball bearings.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2003.11a
• /
• pp.1-4
• /
• 2003

Recently, a structure has been larger and higher under the improvement of construction technique. So, a concrete constructions that a mat foundation thickness of structure is over 80cm have been many. Also, because of the reason high strength concrete, the matter of thermal crack have become an important task to be solved absolutely. In a cause a thermal crack occurrence, there used, mixture of concrete, construction and so forth. In this study, we executed temperature and stress analysis of mat foundation to know the effect the construction condition a thermal crack of mat foundation. And we evaluated quantitatively about the occurrence possibility of thermal crack using the hydration heat analysis program. By using of this analysis technique, will can control skilfully the quality of a mat foundation in advance.

• Journal of the Korean housing association
• /
• v.19 no.1
• /
• pp.89-96
• /
• 2008

This study measured the thermal environment and residents' control behaviors of cooing according to 3 groups of household type-families with preschool children, families of middle age and families of senior. The object of this study are to fmd the difference of the actual condition of indoor thermal environment and cooling control behavior by age or household type and to develop user oriented climate control system. The results were summarized as follows. When the age of members at household is younger, the indoor mean temperature and temperature that people turned off the air conditioner became lower. These different indoor thermal environment of each group means that younger generation is familiar with cooler from their early age and these early uses of cooler made them prefer cooler condition than family of senior. Therefore, this results show that different indoor thermal environment is influenced by factors such as household type and metabolism difference and so on.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.10 no.4
• /
• pp.104-110
• /
• 2001

The objective of this study is structural analysis of continuous casting mold. A two-dimensional finite element model was developed to compute the temperature distribution, thermal stress and thermal strain behavior for continuous casting mold. Structural analysis was made using thermal analysis result, utilizing transient analysis of ANSYS. This structural analysis results, many variables such as casting speed, cooling condition film coefficient, convection and load condition are considered.