• 제목/요약/키워드: intrinsic insulation

검색결과 13건 처리시간 0.026초

The Effect of Adjustable Garment Closures and Layering on Insulation in Cold Weather

  • Kim, Chil-Soon;McCullough, Elizabeth
    • 한국의류산업학회지
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    • 제3권5호
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    • pp.479-485
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    • 2001
  • This study was to determine the effect of garment closures and layering systems on insulation, using a thermal movable manikin in cold weather conditions. The insulation values of ensembles with opened and closed features were measured, and those of four different layered clothing ensembles were tested while standing and while walking. Our research indicated that when there was an opening involved in design the system, insulation decreased; even a zip-out lining in the armpit affected little. If a light weight jacket and pants are put on over a fleece shirt and pants instead polyester underwear, the amount of insulation increase was 0.43 clo.

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수직으로 설치된 비균질 평판 단열재용 성능시험장치 개발 (Development of Thermal Performance Tester for Non-Homogeneous Insulation Pannels Installed Vertically)

  • 오홍영;송기오;전현익;조선영
    • 설비공학논문집
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    • 제28권4호
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    • pp.153-157
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    • 2016
  • In case of metal insulation, which is produced by stacking stainless steel sheets and air layers in a multi-stack manner at a specific thickness, insulation performance will be evaluated based on thermal transmittance rather than the intrinsic physical properties of each material such as thermal conductivity. However, there is no standard for measuring thermal transmittance targeted for non-homogeneous insulation which is used in relatively high temperature conditions such as a power station. In this study, the thermal conductivity of homogeneous insulation acquired by the standardized guard hot plate method and the thermal conductivity of homogeneous insulation measured by the newly developed performance tester were compared to verify the confidence level of the tester. As a result, thermal conductivity acquired by the newly developed thermal transmittance tester was about 6% higher than the thermal conductivity measured by the existing guard hot plate method under the anticipated service temperature conditions.

연료전지 차량의 전기적 절연 특성에 관한 연구 (Study on the Electric Insulation Characteristics in a Fuel Cell Vehicle)

  • 유정한;김덕환;김주한;정귀성;금영범;김세훈;안득균
    • 한국수소및신에너지학회논문집
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    • 제23권2호
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    • pp.150-155
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    • 2012
  • Polymer Electrolyte Membrane Fuel Cell (PEMFC) stack power output is needed to be approximately 100 kW to meet the requirements of automotive applications. In order to secure the electric safety for drivers, passengers and mechanics, it is very important to understand phenomena of an electric insulation in a fuel cell vehicle. In this study, we studied the electric insulation properties and the insulation resistance of stack, system and vehicle in the field of fuel cell was estimated at the applied voltage of 500 V, respectively. Also we discussed the insulation factors such as the conductivity of coolant, the element of vehicle design and the intrinsic resistance of the vehicle components.

A "Fabric-First" Approach to Sustainable Tall Building Design

  • Oldfield, Philip
    • 국제초고층학회논문집
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    • 제6권2호
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    • pp.177-185
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    • 2017
  • This research suggests the most effective way for improving energy efficiency in tall buildings is a "fabric-first" approach. This involves optimizing the performance of the building form and envelope as a first priority, with additional technologies a secondary consideration. The paper explores a specific fabric-first energy standard known as "Passivhaus". Buildings that meet this standard typically use 75% less heating and cooling. The results show tall buildings have an intrinsic advantage in achieving Passivhaus performance, as compared to low-rise buildings, due to their compact form, minimizing heat loss. This means high-rises can meet Passivhaus energy standards with double-glazing and moderate levels of insulation, as compared to other typologies where triple-glazing and super-insulation are commonplace. However, the author also suggests that designers need to develop strategies to minimize overheating in Passivhaus high-rises, and reduce the quantity of glazing typical in high-rise residential buildings, to improve their energy efficiency.

Ionic Passivation and Oxidation Dynamics for Enhanced Viability of Copper-Based On-Skin Bioelectrodes in Biological Environments

  • Jungho Lee;Gaeun Yun;Juhyeong Jeon;Phuong Thao Le;Seung Whan Kim;Geunbae Lim
    • 센서학회지
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    • 제32권6호
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    • pp.352-356
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    • 2023
  • The integration of bioelectronic devices with the skin is a promising strategy for personalized healthcare monitoring and diagnostics. On-skin bioelectrodes hold great potential for the real-time tracking of physiological parameters. However, persistent challenges of stability and reliability have instigated exploration beyond conventional noble metals. This study focuses on the ionic passivation and oxidation dynamics of copper-based on-skin thin-film bioelectrodes. Through parylene chemical vapor deposition, we harness a controlled thin film of parylene insulation to counter the intrinsic susceptibility of copper to oxidation in the ionic environment. The results represent the relationship among the parylene insulation thickness, copper oxidation, and electrode impedance over temporal intervals. Comparative analyses indicate that the short-term stability of the copper electrode is comparable to that of the gold electrode. Therefore, we propose a cost-effective strategy for fabricating copper-based on-skin bioelectrodes by introducing enhanced ionic stability within a discernible operational timeframe. This study enriches our understanding of on-skin bioelectronics and affordable material choices for practical use in wearable healthcare devices.

발한 Thermal manikin과 국제 표준 7730을 이용한 원자력 발전소 작업복의 열적 쾌적성 판별 (Determining thermal comfort properties of coverall worn in the atomic power plant using a sweating thermal manikin and ISO 7730)

  • 홍성애
    • 대한인간공학회지
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    • 제15권1호
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    • pp.91-103
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    • 1996
  • For determining thermal comfort properties of work suit in an atomic power plant, three different coverall ensembles (PVE, PET/Rayon, PP Nonwoven) were selected and the resistance to dry and evaporative heat transfer were measured for each ensemble by using a sweating thermal manikin. Also, PMV (Predicted Mean Vote) and PPD(Predicted Percentage of Dissatisfied) indices were predicted according to ISO 7730. As a result, ideal environmental conditions in an atomic power plant were suggested to make workers feel thermally comfortable. In addition, ideal intrinsic insulation values of coverall ensembles as a work suit under the present environmental conditions in the at6omic power plant were provided. The information given in this paper can be used to control environmental conditions in the atomic power plant thermally comfortable and to select a proper work suit for providing thermal comfort to the workers.

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알루미늄 판상에 글라스 세라믹 후막이 코팅된 절연금속기판의 제조 및 절연특성 (Fabrication and Electrical Insulation Property of Thick Film Glass Ceramic Layers on Aluminum Plate for Insulated Metal Substrate)

  • 이성환;김효태
    • 마이크로전자및패키징학회지
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    • 제24권4호
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    • pp.39-46
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    • 2017
  • 본 연구는 평판형 히터용 금속방열판상의 세라믹 절연층 제조, 즉 절연성 금속기판에 관한 것이다. 반도체나 디스플레이의 열처리 공정 등에 사용되는 평판형 히터를 제조함에 있어서, 온도 균일도를 높이기 위해 금속 방열판으로서 열전도율이 높고, 비교적 가벼우며, 가공성 좋은 알루미늄 합금 기판이 선호된다. 이 알루미늄 기판에 발열 회로 패턴을 형성하기 위해서는 금속 기판에 절연층으로서 고온 안정성이 우수한 세라믹 유전체막을 코팅하여야 한다. 금속 기판상에 세라믹 절연층을 형성함에 있어서 가장 빈번히 발생하는 첫 번째 문제는 금속과 세라믹의 이종재료 간의 큰 열팽창계수 차이와 약한 결합력에 의한 층간박리 및 균열발생이다. 두 번째 문제는 절연층의 소재 및 구조적 결함에 따른 절연파괴이다. 본 연구에서는 이러한 문제점 해소를 위해 금속소재 기판과 세라믹 절연층 사이에 완충층을 도입하여 이들 간의 기계적 매칭과 접합력 개선을 도모하였고, 다중코팅 방법을 적용하여 절연막의 품질과 내전압 특성을 개선하고자 하였다.

Radical Transfer 반응을 이용한 Polypyrrole 효소전극의 효소고정화 향상 (Improvement in Enzyme Immobilization of Polypyrrole Enzyme Electrode using Radical Transfer)

  • 김현철;조영재;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.100-103
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    • 2000
  • In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidase (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized the enzyme electrode by electropolymerization added some organic solvent. A formative seeds of film growth is delayed by adding ethanol. The delay is induced by radical transfer between ethanol and pyrrole monomer. The radical transfer shares the contribution of dopant between electrolyte anion and GOx polyanion. This may lead to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased. We established qualitatively that amount of immobilization can be improved by adding a little ethanol in the synthetic solution. It is due to radical transfer reaction. The radical transfer shares the contribution of dopant between small and fast electrolyte anion and big and slow GOx polyanion.

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유기용매 첨가에 따른 Polypyrrole-Glucose Oxidase 효소전극의 효소고정화 향상 I. 자외선 분광분석 (Improvement on Enzyme Immobilization in Polypyrrole-Glucose Oxidase Enzyme Electrode using Organic Solvent Additive I. Ultraviolet Spectroscopic Analyses)

  • 김현철;구할본
    • 한국전기전자재료학회논문지
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    • 제15권7호
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    • pp.615-620
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    • 2002
  • In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidise (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized enzyme electrodes by electropolymerization added some organic solvent, such as ethanol and tetrahydrofuran (THF). The formative seeds of film growth was delayed by adding ethanol. The delay was induced by radical transfer between ethanol and pyrrole monomer. The radical transfer reactions shared the contribution of dopants between electrolyte anion and GOx polyanion. This led to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased.

HVDC용 나노복합 절연재료의 DC절연파괴 분석 (Analysis of DC dielectric breakdown strength of Nano-composite insulation material for HVDC Cable)

  • 조성훈;정의환;이한주;임기조;정수현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.104-104
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    • 2010
  • With the advent of nano-particle fillers in insulating materials, the insulating materials of superior quality have come to fore. In the recent past, nanocomposite LDPE/XLPE (Low Density Polyethylene/Cross Linked Polyethylene) power cable dielectrics have been synthesized. A preliminary evaluation of these new class of materials seem to show that, addition of small amounts of sub-micron inorganic fillers improved the dielectric properties of the composite, in particular, the volume resistivity, and the DC breakdown strength. The thermal behaviour, for example, the stability of composites against decomposition and ensuing electrical failure, do not seem to have been addressed. In a conventional XLPE insulated cable, the average thermal breakdown strength and maximum temperature at the onset of breakdown were seen to be markedly lower than the corresponding intrinsic breakdown strength and decomposition temperature. In this page, analysis of DC Breakdown of nano-composite insulating material for HVDC Cable is introduced.

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