• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.8
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• pp.1110-1118
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• 1999

This study was to examine the effects of garment types on thermal insulation using a thermal manikin. cotton polyester wool silk and rayon were selected as outer wears like a blouse a skirt slacks and one-piece for this study Acetate was chosen as a lining. Brief and upper innerwear with long sleeves(cotton) were also chosen as the innerwear. The results were as follows: 1. The thermal insulation of the garment of single layer was in proportion to the covering area of garment in all types of clothing. 2. On adding the innerwear or the lining or both the thermal insulation of the each garment of single layer were showed a different trends by garment types. The thermal manikin insulations of one-piece dress adding the innerwear was higher than those of blouse-skirt suits. The thermal insulation of one-piece dress adding the innerwear and lining was lower than those of blouse-skirt suits. 3. The increasing rates of thermal insulation of multi-layered garments had different value by garment types but garment made of rayon and silk were showed very high increasing rates of thermal insulation. 4. The increasing rates of the thermal insulation of one-piece dress added the lining the innerwear or both except polyester showed the highest value and then blouse-slacks suits' turn came ound Blouse-skirt suits had the lowest the increasing rates of thermal insualition value.

• Journal of Hydrogen and New Energy
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• v.28 no.5
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• pp.512-520
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• 2017

This paper is a numerical study of various methods of applying SOFC hot BOP insulation. The application methods are four cases from case 1 to case 4, and the performance difference between the result of applying powdered insulation and the result of zoning using composite multi-layer insulation was examined. Numerical results show that the thermal stability of composite multi-layer insulation is better than that of powder insulation when the thermal conductivity is 0.04 W/mK. In the future, we will increase the thermal conductivity of the composite multi-layer thermal insulation material and find the greatest value of thermal conductivity with a similar result to that of the powder insulation.

• KIEAE Journal
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• v.9 no.6
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• pp.13-18
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• 2009

Korean traditional houses have been developed in harmony with natural environment and comfortable indoor condition by using the natural resources including building layout, space composition and materials. Originally Korea traditional architectures have used wood lintel constructions and loess walls through the many years. Theses loess have many strength such as highly heat capacity, controling of humidity, a deodorant than any other materials. Nowaday it is recommended to use exterior and interior walls in loess wall to meet the eco-friendly materials to improve our residental environmental. Thus this study aims to research the sound insulation performance of traditional loess brick wall varied with thickness, thermal insulation materials and cavity wall. The sound insulation performance of these loess walls are compared with other masonry wall's and sound insulation performance of th walls were tested in anechoic laboratory to measure the sound transmission loss of these walls. The loess brick wall with 75mm thickness of cavity is shown the sound insulation performance with Rw 57 which is nearly same performances of 1B brick wall and cement 8' block wall, The improving effect of insulation materials is shown in the high frequency bandwidth. Especially, there is improving as much as 11 dB using the extruded poly stylene form(75mm) and poly ethylene film(0.7mm).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.9
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• pp.783-789
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• 2003

The winding problems of traction motor are the major determinant of motor's life. The root cause of winding failure is gradual deterioration of the insulation due to thermal, electrical, mechanical and environmental stresses. The aging of the insulation reduces the electrical and mechanical strength of the insulation. At same point, a voltage surge or mechanical shock from a traction motor start will fracture or break down the insulation. To achieve the expected life usually requires extensive laboratory evaluation of the insulation systems and the use of accelerated aging tests. There are several nondestructive test available for checking, the condition of motor insulation, the probable extent of aging, and the rate of which aging is taking place. So the insulation characteristics of stator coil were each analyzed by measurement of dielectric loss(tan$\sigma$), capacitance and partial discharge. The method of diagnosis is able to analyze the insulation condition and evaluate the life of the traction motor.

• Journal of the Korean Ceramic Society
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• v.47 no.5
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• pp.373-380
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• 2010

In this study, we studied on the durability of restorative cement mortar for deteriorated concrete at complex deteriorated conditions as variation of temperature and of humidities. We made a comparison between restorative materials with insulation function and restorative materials without insulation function in items of compressive and bending strength and permeability of water, durability for carbonation, salt damage, diffusion coefficient of salt at complex deterioration conditions like change of temperature, change of humidity, For insulation, we used close-pore type Alumino-Silicate lightweight aggregate and substituted 12 wt% and 15 wt% out of original restorative cement mortar without insulation function. As a result, it was found that original restorative cement mortar without insulation function fail to meet Korean Standard on polymer modified cement mortar for maintenance in concrete structure, but restorative cement mortar with insulation function is in contentment Korean Standard to meet excellent than restorative materials without insulation function for durability at complex deteriorated conditions.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.11
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• pp.735-741
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• 1999

The monitoring and assessment on the insulation condition of generator stator windings have been an important task of utility companies. The interest for the assessment of insulation condition has been increasing due to the need to keep old generating equipment reliable in order to extend the equipment life and to increase the generating capacity. Even though many developments and research activities for the condition assessment of generator insulation have been performed for decades, the assessment criterion in order to consistently predict the actual insulation condition is still in question. In this paper, the correlation between the parameters and the insulation condition is analyzed through the various non-destructive diagnostic tests in order to establish the assessment criterion on insulation deterioration of generator stator windings. By analyzing the correlation, PDI(Partial Discharge Index) as a novel parameter for the assessment criterion on insulation diagnosis of stator winding is proposed and verified.

• Transactions on Electrical and Electronic Materials
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• v.15 no.1
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• pp.7-11
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• 2014

The Polarization and Depolarization Current (PDC) measurement is an efficient and effective diagnostic technique based on time domain measurement, for evaluating the high voltage insulation condition. This paper presents a review and comparison results from several published papers on the application of the PDC method to finding the conductivity and moisture content of various types of insulators. For solid insulation, the study was focused on cable insulation, electric machine stator insulation, and paper insulator in transformer insulation with different conditions. For liquid insulation, the review and comparison was done on biodegradable and mineral transformer oils, with fresh oil condition, and aged condition. The results from previous researchers tests were complied, analyzed and discussed, to evaluate the application of the PDC method to monitor the conductivity and moisture of HV equipment insulation systems. From the review results, the PDC technique successfully gives an indication of the conductivity and moisture level of high voltage insulation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.87-88
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• 2019

Research has been conducted in many fields for the zero energy of domestic buildings. Among them, the development of insulation has become an essential element. Accordingly, researches are being made to improve the performance of organic insulating materials, and PF boards having the lowest thermal conductivity among organic insulating materials have been in the spotlight. However, problems have arisen due to the problems of durability of insulation materials such as PF boards and past acidification, and the durability of insulation materials is deteriorated when moisture or water enters due to crack gaps during the insulation of the basement layer or the external insulation method. In regard to the durability of the insulation, when the organic insulators of different kinds were placed in water, the pH was weakly basic in all organic insulation materials except PF, and the PF was about 4 pH. As a result, the PF should be continuously reviewed, and further analysis should be carried out to determine what causes acidification.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.787-793
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• 2021

The global demand for Liquefied Natural Gas(LNG) continues to increase and is facing a big cycle. To keep pace with the increase in international demand for LNG, the demand for LNG fueled ships is also increasing. Since LNG fuel tanks are operated in a cryogenic environment, insulation technology is very important, and although there are various types of insulation applied to Type C tanks, multi-layer insulation and vacuum insulation are typically applied. Powder insulation materials are widely used for storage and transportation of cryogenic liquids in tanks with such a complex insulation structure. In this study, compression tests at room and cryogenic temperature were performed on closed perlite, glass bubble, and fumed silica, which are representative powder insulation material candidates. Finally, the applicability to the Type C fuel tank was reviewed by analyzing the experimental results of this study.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.264-273
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• 2016

The insulation of a building envelope influences the hygrothermal performance as well as the thermal performance of the building. While most of Korean wood frame houses have an interior insulation system, the exterior insulation system with high thermal performance has recently been applied. While it can be effective in energy savings for better insulation performance, without consideration of the moisture, condensation and mould growth can occur. Therefore, in this study, hygrothermal behaviour, water content, and mould growth were analyzed using hygrothermal simulation of an exterior wall of a wood frame house with which the interior insulation and exterior insulation systems were applied. The wall layer included Wall A (Interior insulation) and Wall B (Exterior insulation). The U-values were identified as 0.173 and $0.157W/m^2K$, respectively. The total water content and OSB absolute water content of Wall A were confirmed to be higher than those of Wall B, but the absolute water content did not exceed the reference value of 20%. The moisture content of the two walls was determined to be stable in the selected areas. However, mould growth risk analysis confirmed that both Wall A and Wall B were at risk of mould growth. It was confirmed that as the indoor setting temperature decreased, the mould index and growth rate in the same area increased. Therefore, the mould growth risk was affected more by indoor and outdoor climate conditions than by the position of the insulation. Consequently, the thermal performance of Wall B was superior to that of Wall A but the hygrothermal performances were confirmed to be similar.