• 한국세라믹학회지
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• 제50권1호
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• pp.57-62
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• 2013

We investigated the thermal and electrical properties of the $B_2O_3-ZnO-Bi_2O_3$ glass system as a sealing material in sheath heater modules. A composition with over 90 wt% $Bi_2O_3$ in the $B_2O_3-ZnO-Bi_2O_3$ system was glassified by controlling the cooling rate. The glass transition temperature and thermal expansion coefficient in bismate glass could be controlled by the minor ingredients of ZnO, $SiO_2$, $BaO_2$, and $K_2O$. The $B_2O_3-ZnO-Bi_2O_3$ glass system bonded well to metal, and bismate glass insulating properties were comparable to those of bismate glass $B_2O_3-ZnO-PbO$ glass system in a sheath heater module.

• 한국태양에너지학회 논문집
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• 제39권2호
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• pp.45-55
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• 2019

More than 76% of the detached houses in Korea are over 20 years old. These old detached houses have poor energy efficiency. According to the 2017 Housing Census (Statistics Korea), more than 50% of low-income families live in detached houses. Therefore, the improvement of energy efficiency in old detached houses is needed from the viewpoint of energy welfare. The general method of building energy modelling for the verification of energy efficiency is based on the construction year data of "Building Design Criteria for Energy Saving" due to the cost and time involved in collecting the thermal performance data of buildings. There is poor accuracy with the deterioration of long-term aging of building materials. Also, the selection of alternatives for energy performance improvement is based on the items to be applied, not a performance improvement goal. It is difficult to calculate energy performance that reflects variations in various parameters with dynamic energy simulations. In this study, the influence of long-term aging is used to accurately predict the energy performance of old detached houses. The building energy modelling method is called ENERGY#, which is a static analysis method based on ISO13790. Energy performance is evaluated by a combination of input variables including building orientation, insulation of walls and roof, thermal performance of windows and window/wall ratio, and infiltration rate. Finally, this study provides a way to determine alternatives that meet energy performance improvement goals.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1982-1984
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• 2004

Stator coil of rotating machinery has shown different characteristics according to impregnated with coil or not. And this is major determinant of equipment's life. In this paper, PD characteristics is studied as a classification scheme between two specimens. Processing of the coil impregnation is very important thing because that influences on thermal and electrical characteristics of the coil. And then PD is occurring at the coil and causing insulation degradation. For processing statistical processing, PD data acquired from PD detector using PDASDA(partial discharge acquisition, storage and display system). And also these statistical distribution and parameter are applied to classify PD sources by neural networks. As a result of, Neural Networks have a good discrimination rate for classification PD sources.

• 한국레이저가공학회지
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• 제14권1호
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• pp.25-29
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• 2011

Micromachining of photosensitive glass by UV exposure, heat treatment, and etching processes is reported. Like photoresist, the photosensitive glass is also classified into positive and negative types by development characteristics. For the positive type, the exposed area is crystallized and etched away during the etching process in HF solution, whereas the unexposed area is crystallized and etched away for the negative type. The crystallized area of the photosensitive glass has an etch rate approximately 30~100 times faster than that of the amorphous area so that it becomes possible to fabricate microstructures in the glass. Based on the unique properties of glass such as high optical transparency, electrical insulation, and chemical/thermal stability, the glass micromachining technique introduced in this work could be widely applied to various devices in the fields of electronics, bio engineering, nanoelectonics and so on.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.165-166
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• 2018

Researches for the development of renewable energy as a fuel substitute for global warming and depletion of petroleum resources are actively being carried out. Among them, the annual growth rate of PV generation is 20.73%, which is higher than other renewable energy sources. However, the production of 1 ton of polysilicon, which is known as a raw material for solar power generation panels, generates 2 tons of waste. As the demand for PV panels increases, the problem of the treatment of polysilicon sludge is attracting attention, and studies on the utilization of polysilicon sludge are needed. Therefore, in this study, the applicability of polysilicon sludge treated as industrial waste to the lightweight panel for architectural purposes was examined.

• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.61-67
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• 2005

The purpose of this study is to evaluate the air tightness of Zero Energy Solar House(ZeSH) and to propose the construction improvement of junctions and penetrations where air infiltration was identified. Air leakage rate were measured by means of blower door test in accordance with ASTM E779-87. The results showed that ZeSH has an excellent airtightness with ACH50/20 (air change per hour at a pressure difference of 50 Pa between inside outside) of 0.34hr-1 and leakage class E by normalized leakage area of ASHRAE.

• 폴리머
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• 제33권1호
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• pp.79-83
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• 2009

Hexamethyldisiloxane(HMDSO)+$O_2$를 플라즈마 중합시켜 알루미늄 판과 알루미늄 콘덴서 케이스 표면에 전기 절연박막을 코팅하였다. 코팅된 박막들은 두께가 0.5 ${\mu}m$ 이상이면 박막의 종류에 상관없이 1.0 M$\Omega$ 이상의 저항 값을 보였으며, 박막의 표면 형태 및 접착력은 플라즈마의 공정조건에 따라 달라졌다. 박막의 증착속도 및 접착력은 $O_2$/HMDSO 유량비와 방전전력에 따라 달라졌으며, 유량비가 4이고 방전전력이 60 W일 때 가장 좋은 결과를 보였다. 집착력은 또한 알루미늄을 끓는 물에서 30분간 전처리한 경우에 박막과 알루미늅 표면 사이에 Al-O-Si 결합을 형성하면서 크게 향상되었다. 이렇게 코팅된 박막은 우수한 내약품성과 내열성을 지니고 있었다.

• 한국건축시공학회지
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• 제18권5호
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• pp.413-418
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• 2018

이 기초 연구는 시멘트 페이스트의 초기강도 향상 및 열전도율 향상을 위한 흄드 실리카의 첨가에 대한 적용성 및 문제점을 평가하기 위한 것이다. 주요 변수인 흄드 실리카 는 시멘트 질량 대비 0%에서 1.6%까지 0.4% 간격으로 첨가하였다. 실험결과, 흄드 실리카의 첨가는 시멘트 페이스트의 초기강도 발현에 효율적이었는데, 재령 1일 압축강도는 28일 강도의 약 45%이었다. 이 높은 초기강도 발현율은 증기 양생 시멘트 콘크리트의 경우와 비슷한 수준이다. 하지만 흄드 실리카의 첨가가 시멘트 페이스트의 열전도 저항성 향상에 미치는 영향은 무의미 하였다.

• 토지주택연구
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• 제12권2호
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• pp.99-108
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• 2021

이 연구의 목적은 한옥 거주환경의 쾌적성능에 대한 정량적 자료를 제시하고 개선 요인을 도출하는 데 있다. 먼저 정책적 성공사례로서 현대(신(新))한옥의 하나인 전남 화순군 잠정햇살마을 한옥단지를 대상으로 건구온도, 복사온도, 상대습도, 풍속 등 열쾌적성 평가의 영향 요소를 측정했다. 이어 도출 데이터를 적용하여 PMV(Predicted Mean Vote)를 산출하는 열환경 시험을 수행했으며, 사용자 대사율과 의복량을 변수로 설정하여 L.C.PMV(Life-Cycle PMV)와 N.PMV(Normal PMV)의 두 가지 유형으로 구분하여 평가를 진행했다. 그 결과, 여름 및 겨울철 시점을 전후하여 한옥 공간의 PMV 증감 동향이 뚜렷했으며, 특히 대서 및 대한 시점의 PMV는 쾌적구간을 완전히 벗어난다는 시험 결과를 확인했다. 아울러 겨울철 PMV의 변화 속도가 여름철보다 더 빠른 것으로 나타났다. 이러한 결과를 통해 신한옥의 쾌적성능 증진을 위해 단열성 개선이 우선 요인임이 도출되었으며, 설계 및 시공 단계에서 연계 검토가 요구된다.

• 한국의류산업학회지
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• 제1권3호
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• pp.288-295
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• 1999

This study was conducted to examine the fatigue phenomenon of mechanical properties in tencel fabrics by repeated washing & shear and tensile deformation. The obtained results are as follows. After performing repeated shear tensile deformation, RT of tencel showed higher increase rate than that of cotton and rayon, whereas its WT and EM was a smaller decrease rate than that of them. This means that tencel's resistance to tensile deformation was the greatest. In the repeated washing and shear tensile deformation, tencel's 2HB, 2HG and 2HG5 showed a remarkable increase rate. In terms of deformation frequency, the greatest change rate appeared at the time of 1000 cycles of repeated shear tensile deformation and 15 times of repeated washing. In the hand value and THV, KOSHI showed a higher increase rate for tencel than for cotton and rayon in both repeated washing and shear tensile deformation, and NUMERI showed a higher increase rate. In the THV the change rate of rayon and cotton could be rarely seen but for tencel, it decreased. tencel's change rate of thermal insulation value by materials was 1.08%, and it increased as the washing frequency increased, compared to the grey fabrics, whereas the change rates of cotton and rayon were 0.74% and 0.22%, respectively. The qmax decreased in the order of cotton>tencel>rayon as the washing frequency increased.