• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.4-5
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• 2021

In this study, in the coating-sheet composite waterproofing method, a specimen was formed to prevent the transmission of the no-node tensile stress occurring under the junction between sheets by forming an insulating structure when the junction was formed, and to compare the effect of preventing breakage with the existing common junction. For this, tensile performance evaluation was conducted. As a result of the evaluation, it was confirmed that it exhibited higher tensile strength compared to the existing joint and at the same time exhibited a large width of displacement characteristics, and thus, had an effect of preventing breakage.

• 한국농촌건축학회논문집
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• 제20권1호
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• pp.11-18
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• 2018

The study aims to address the energy crisis and realize self-sufficiency of building as part of local energy independence, breaking away from a single concentrated energy supply system. It is intended to develop modules of the outside insulation composite panels that conform to passive certification criteria and for site-assembly systematization. The method of study first identifies trends and passive house in literature and advanced research. Second, the target performance for development is set, and the structural material is selected and designed to simulate performance. Third, a test specimen of the passive outside insulation curtain wall module designed is manufactured and constructed to test its heat transmission coefficient, condensation performance and airtightness. Finally, analyze performance test results, and explore and propose ways to improve the estimation and improvement of incomplete causes to achieve the goal. The final test results achieved the target performance of condensation and airtightness, and the heat transmission coefficient was $0.16W/(m^2{\cdot}K)$, which is $0.01W/(m^2{\cdot})K$ below the performance target. As for the lack of performance, we saw a need for a complementary design to account for simulation errors. It also provided an opportunity to recognize that insulated walls with performance can impact performance at small break. Thus, to be commercialized into a product with the need for improvement in the design of the joint parts, a management system is needed to increase the precision in the fabrication process.

• 콘크리트학회지
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• 제25권6호
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• pp.40-43
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• 2013

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.244-247
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• 2004

The electrical insulating design is important to realize a HTS power cable because the cable is operated under the high voltage environment. For the insulation design of a HTS power cable, it is necessary to investigate the AC, impulse breakdown and partial discharge(PD) inception stress of liquid nitrogen/LPP composite insulation system. Based on these results, the electrical insulation of a HTS power cable is designed and Mini-model cables are manufactured. The manufactured Mini-model cables are evaluated that AC, impulse withstand voltage, breakdown and partial discharge inception stress and analyzed characteristics insulation of HTS cable bending condition according to this paper. From these tests, the AC, impulse withstand voltage test and partial discharge inception stress is satisfied "standard technical specification of KEPCO" in Korea and the breakdown voltage was 120kV.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권1호
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• pp.15-20
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• 2004

This paper discusses electrical insulation characteristics at cryogenic temperature, especially focusing on partial discharge (PD) inception characteristics, for high temperature superconducting cables. In liquid nitrogen (L$N_2$) / polypropylene (PP) laminated paper composite insulation system, PD inception strength (PDIE) was evaluated in terms of volume effect and V-t characteristics. Different kinds of butt gap condition were applied in the experiments, using parallel plane and coaxial cylindrical cable samples. Experimental results revealed that the volume effect on PDIE could be evaluated by the statistical stressed liquid volume (SSLV) taking account the discharge probability not only in the butt gap but also in the other thin layers between PP laminated papers. Furthermore, the indices n of V-t characteristics at PD inception were estimated to be 80∼110, irrespective of the butt gap condition.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.479-482
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• 1999

Cured epoxy resins are extensively used for the electrical insulation in high-voltage equipments. The bisphenol A-based epoxy resins lured with azine show, especially, good thermal properties and mechanical resistances. For the technical and economic reasons, varing amount of inorganic fillers are added to endow the required special properties. In the large generators and motors of power plants, epoxy insulation is disclosed to the harsh conditions like the superheated steam and abrupt temperature variation. Hygrothermal aging at elevated temperatures tends to induce degradation in epoxy resins. To predict the effect of this degradation in DGEBA/MDA/SN/zeolite system, we proceeded the forced moisture absorption experiment using the autoclave. The thermal properties of the untreated and treated specimens were analyzed by DSC and TGA under the nitrogen flowing condition. The moisture absorption results showed a weight increase during hygrothermal aging at 1207. At the initial aging period, the system leaded to more or less postcuring but more prolonged environmental aging leaded the discoloration of specimen and lowering the T$_{g}$./.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.239-242
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• 2005

This paper introduced an approach of improvement of performance of Electric device for EMU type Train like as TTX. The electric equipments are characterized by insulation, Noise, cooling system etc. and Their weight arc decided by these factors. There are two kinds of power source in EMU train. First, DC voltage source, 1500 volt, 750 volt is used for subway system. Second, AC power source 25000 volt is applied to high speed train and existing main lines. Composite material has the protection of inrush current and high frequency noise. We can use this material to minimize weight of train. Additionally we can get energy saving when operator service TTX.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.539-543
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• 2011

LNG cargo containment system (CCS) has the primary function of ensuring adequate thermal insulation with keeping natural gas below its boiling point. From the viewpoint of structural design, this LNG CCS can be treated as a laminated composite structure showing complex structural responses under the sloshing load which can be defined as a violent behavior of the liquid contents in cargo tanks due to external forced motions. As LNG CCS type, Mark III containment system from TGZ is considered in this paper and then its structural strength assessment is performed based on a simple higher-order shear deformation theory and maximum stress, maximum strain, Tsai-Wu failure criteria developed for laminated composite plates. The assessment is performed to the initial failure of the Mark III CS plate by investigating failure locations and loads.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.227-230
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• 1998

The effects of post curing conditions on thermal properties of alumina filled epoxy resin system DGEBA/MDA/SN were investigated. As the post curing time increased at 15$0^{\circ}C$, the glass transition temperature increased from 121 to 124, slightly. As the heating rate increased, high thermal decomposing temperature (T$_{d}$) and most decomposing temperature (T$_{p}$) increased. For the case of post-cured system at 15$0^{\circ}C$ for 4 days showed lower values than virgin system. At the post curing condition the system must have been thermally degraded.ded.

• Composites Research
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• 제32권2호
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• pp.90-95
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• 2019

LNG 운반선의 슬로싱 충격하중은 LNG 화물창 내 단열시스템의 파손을 야기하는 주원인이다. 단열시스템의 파손은 LNG 화물창 내 극저온을 유지시키는 데 치명적으로 작용하게 된다. 극저온을 유지하기 위해서는 단열재료의 성능 강화가 가장 전형적인 방법이다. 일반적으로 LNG 화물창 내의 단열재료는 폴리우레탄 폼과 플라이우드, 이 두 재료를 접합시키기 위한 접착제가 사용된다. 본 연구에서는 단열시스템에 채용되는 단열재료를 강화하기 위한 일환으로 글라스 버블/에폭시 복합수지를 제작하여 충격 하중이 작용할 때 재료의 흡수에너지를 향상시켰다. 실험 시나리오는 글라스버블의 첨가량, 온도의 영향성을 분석하기 위한 상온 및 극저온 환경을 고려하여 자유낙하 실험을 수행하였다. 실험 결과는 글라스 버블 첨가량이 20 wt.%에 도달할 경우 극저온 흡수에너지가 최대의 성능이 나타나는 것을 확인하였다. 반면에 상온 흡수에너지는 첨가량 0 wt.%에서 최대 성능을 보였다. 글라스버블/에폭시 수지의 혼합성능의 경우 첨가량이 20 wt.%가 되면 교반성능 저하로 인하여 응집현상이 발생하여, 접착성능이 떨어질 것으로 판단된다.