• Transactions on Electrical and Electronic Materials
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• 제7권5호
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• pp.262-266
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• 2006

The insulation diagnostic test and the AC breakdown test were performed under off-line using the 3.3 kV class induction motor which have been served for 10 years. These tests were conducted in means of nondestructive and destructive test. In this paper, we compared the correlation between the nondestructive and destructive test. Furthermore we setup an experimental condition with moisture and compared the insulation characteristics between moist and dry sample. From the results of the nondestructive and destructive test, it was found that the second AC current, which is the previous step of insulation breakdown, suddenly increased at a point of around 8.5 kV. The insulation breakdown of moist sample occurred at 12-14 kV, which is 4-5 kV lower than dry sample.

• 전기학회논문지
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• 제65권10호
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• pp.1688-1693
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• 2016

In this study shall investigate the influence upon the electrical property of transformer oil due to the heat among accelerated heat degradation experiment for a constant hour in the typical insulation oils of mineral base oil, silicon base oil and vegetable oil. In addition, the electric insulation performance of insulation materials in transformer shall be evaluated through the electric property analysis according to the heat degradation of epoxy insulation material, which has been used for electric facilities such as a molded transformer.

• 소음진동
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• 제11권2호
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• pp.307-314
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• 2001

This study aims to provide fundamental data for enhancing the sound insulation performance of windows. For this study, windows composed of various types and thicknesses, were classified into five categories； fixed, single, double, triple and airtight, and then tested. In order to analyze their sound insulation characteristics and performances. test results were rated using methods such as D, STC, Ts and arithmetical mean. It was found that the sound insulation performance of windows is affected due to their type rather than the thickness of the glass. It was also found that when gap between the inner and outer frames was filled with caulking material, the sound transmission loss at high frequency bands was greatly improved. Therefore, the sound insulation performance of windows would be enhanced by minimizing the gap between frames.

• 대한기계학회논문집
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• 제18권4호
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• pp.986-996
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• 1994

Insulation system of LNG carrier has made important roles such as maintaining a proper Boil off Ratio(BOR) for the cargo and avoiding the excessive low temperature of the adjacent inner hull beyond the permissible limit. At the same time, safety and economy of the LNG transportation by the ship are connected with the performance of the insulation system. Also, thermal insulation system of LNG carrier is one of the most advanced technique with the structure analysis of tank, welding and assembling. In this study a computer program is developed to calculate the hull temperature distribution and BOR, which are important factors in thermal design for the Moss Rosenberg Verft spherical tank type LNG carrier. Detailed results for hhull temperature distribution close to LNG tank, BOR and the thickness effect of insulation material are reported in this paper in the range of standare design sea condition.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1139-1146
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• 2008

Due to the construction technique (or the construction culture) growth in and out of Korea, newly-developed insulation have been continuously released. Furthermore, all legislation and regulation that World follows are gradually becoming unified. (e.g. FTA(Free Trade Agreement) with the United States was contracted, and inevitable FTA contraction with EU and China). In addition, insulation type, with the purpose are becoming unified. Accordingly, KS F 2803 legislated in 1966 about the Domestic Insulation Standard including traditionally used insulation(Rockwool, Fiberglass, Polystrene, Polyurethan, Perlite) has to be amended by considering International Standard and the alternatives. This reference is going to make description for solution of contradiction.

• 한국소음진동공학회논문집
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• 제12권8호
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• pp.573-580
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• 2002

Generally the ceiling frame of apartment house is made of wood. But the wood frame has several problems due to the natural properties such as distortion by shrink, low fire resistance and material loss in the construction field. And it has some defections in sound insulation performance. Therefore it is necessary to develop a new method that can be used as a ceiling frame. This study aims to analyze and to compare the sound insulation characteristics against the floor impact sound between wood ceiling frame and M-bar frame which is made of steel. The results of this study are like these. M-bar frame is more effective than wood ceiling frame in sound insulation. And sound absorbing or sound insulation materials which can be Put on gypsum board are helpful to improve floor impact sound insulation performance.

• Transactions on Electrical and Electronic Materials
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• 제14권2호
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• pp.101-104
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• 2013

The effect of the mixing ratio of spherical silica on the electrical insulation breakdown strength in an epoxy/silica composite was studied. Spherical silicas with two average particle sizes of $5{\mu}m$ and $20{\mu}m$ were mixed in different mixing ratios, and their total filling content was fixed at 60 wt%. In order to observe the dispersion of the silicas and the interfacial morphology between silica and epoxy matrix, scanning electron microscopy (SEM) was used. The electrical insulation breakdown strength was estimated in sphere-sphere electrodes with different insulation thicknesses of 1, 2, and 3 mm. Electrical insulation breakdown strength decreased with increasing mixing ratio of $5/20{\mu}m$ and the thickness dependence of the breakdown strength was also observed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.58-59
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• 2019

Data on basic properties are needed due to the increased interest of insulation materials, but In Korea, there are fewer data related to the basic properties of insulation. so the absorption rate was measured every seven days by selecting some of the insulation among insulation materials to provide basic data on absorption rates among basic properties. Measured over 43 days, both absorption and weight showed the highest PF levels, other insulation is judged to have almost reached the maximum absorption rate. PF is still an increasing trend and requires constant observation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.165-166
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• 2019

Curtain wall means a non-bearing wall that forms the outer walls of a building to divide the exterior and interior space. The increased use of curtain walls is diverse, including structural safety, watertightness, and wind pressure. As the government's energy conservation policy and the aim of zero-energy houses, the importance of heat reduction is also greatly increased. So, the study of monotony is constantly being conducted. Thus, in this study, insulation performance was analyzed through simulation according to the shape of curtain wall and the shape of insulation inside, and the purpose of this study was to provide basic data on the application of insulation criteria by energy saving design of buildings.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.51-55
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• 2007

In this paper Statistical Energy Analysis has been considered to predict high frequency air borne interior noise. Dash panel Insulation is major part to reduce engine excitation noise. Transmission loss and absorption coefficient are considered to predict dash insulation performance. Transmission lose is derived from coupling loss factor and absorption coefficient is derived from internal damping loss factor. Material Biot properties were used to calculate each loss factors. Insulation geometry thickness distribution was hard to measure, so FeGate software was used to calculate thickness map from CAD drawing. Each predicted transmission losses between conventional insulation and light weight insulation were compared with SEA. Transmission loss measurement was performed to validate each prediction result, and it showed good correlation between prediction and measurement. Finally interior noise prediction was performed and result showed light weight insulation system can reduce 40% weight to keep similar performance with conventional insulation system, even though light weigh insulation system has lower sound transmission loss and higher absorption coefficient than conventional system.