• 한국방재학회:학술대회논문집
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• 한국방재학회 2010년도 정기 학술발표대회
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• pp.91.1-91.1
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• 2010

본 연구에서는 수직 밀폐형 지중 열교환기를 현장 시험시공하고 현장 열응답 시험을 수행하여 보어홀과 지반의 유효열전도도를 측정하였다. 뒤채움용 그라우트재는 벤토나이트와 시멘트가 고려되었으며 첨가제로는 천연규사와 흑연을 사용하고, 지중 열교환기 파이프 단면은 일반적으로 시공되는 U-loop 파이프 단면과 파이프 사이의 열간섭 효과를 최소화 한 3공형 파이프 단면이 착용되었다. 시멘트-천연규사 그라우트재가 벤토나이트-천연규사 그라우트재 보다 큰 유효열전도도를 보이고 흑연을 첨가한 그라우트는 시멘트와 벤토나이트 모두에서 천연규사만 첨가하였을 때 보다 유효열전도도가 높게 나타났다. 3공형 파이프 단면의 경우 단면에 따른 영향을 비교하기 위해 그라우트는 시멘트-천연규사와 벤토나이트-천연규사를 사용하였으며 유효 열전도도 측정결과 각각 3.65 W/mK, 3.40 W/mK으로 일반 U-loop 파이프 단면을 사용하였을 때 보다 높게 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.1-4
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• 2005

This research is to present experimental materials model of high strength concrete for prediction of fire safety of structural members based on physical properties of materials during heating up to 800$^{circ}C$. The following conclusions are drawn from this study. First of all, between 100 to 200 $^{circ}C$, the physical models of concrete such as specific heat and thermal conductivity, show visible degradation, regardless of concrete strength. Second, between 300 to 600$^{circ}C$, the physical models of the 29MPa and 49MPa concrete show degradation continually at these temperatures. Finally, beyond 600$^{circ}C$, the physical models of 49MPa strength concrete show larger degradation than 29MPa strength concrete due to rise of pore pressure and melting of the interface between aggregate and cement paste.

• The Korean Journal of Ceramics
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• 제3권1호
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• pp.18-20
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• 1997

The fabrication process of silicon-diamond(SOD) structure wafer were studied. Microwave plasma chemical vapor deposition (MWPCVD) and annealing technology were used to synthesize diamond film with high resistivity and thermal conductivity. Bonding and etchback silicon-on-diamond (BESOD) were utilized to form supporting substrate and single silicon thin layer of SOD wafer. At last, a SOD structure wafer with 0.3~1$\mu\textrm{m}$ silicon film and 2$\mu\textrm{m}$ diamond film was prepared. The characteristics of radiation for a CMOS integrated circuit (IC) fabricated by SOD wafer were studied.

• 조명전기설비학회논문지
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• 제28권11호
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• pp.26-32
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• 2014

In electrolysis smelting plants that using high DC current, the bus bar is most important facility for delivering the high current. The copper made bus bar is widely used for various advantages as good electrical and thermal conductivity, resonable malleability, ductility, and not rust easily. However, when high current in copper bus bar, temperature rises and maximum allowable current capacity is restricted by temperature of bus bar. In this paper, we investigated temperature variation of copper bus bar by putting cooling water channel imposed to bus bar construction. For the validity, various simulations were carried out.

• 전기학회논문지P
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• 제59권3호
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• pp.317-324
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• 2010

It was used as measuring system to diagnose insulating condition, by which was kept a insulating resistance of inner stack and at the same time was cooled electrochemical heat of reaction of FCEV(fuel cell electric vehicle) stack that used a compressed hydrogen gas reacting with oxygen in accordance with variation on thermal degradation of nonconductive heat transfer fluid. Consequently it was developed a cylindrical multi-terminal capacitive-conductive sensor that could be attached to the internal surface of cooling system pipe to evaluate capacitance and conductivity of heat transfer fluid.

• 전기학회논문지P
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• 제63권4호
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• pp.327-332
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• 2014

In this paper, the temperature distribution according to the property change of the insulating oil of the power transformer and max temperature were predicted through the ductility interpretation which heat-flow is coupled. By using CFD (Computation Fluid Dynamics) for the interpretation, the temperature distribution of 154kV the class single phase power transformer was predicted. The power loss causing the temperature rise of the transformer was changed to the heat source and we used as the input value for the heat-flow analysis. The temperature distribution was predicted according to the change of the density, specific heat, thermal conductivity and viscosity, that is the ingredient having an effect on the temperature rise of the transformer oil. The mineral oil of 4 kinds used in domestic and international based on the interpreted result was selected and the temperature distribution according to each load and Hot Spot temperature was predicted.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.691-693
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• 2007

We report on a highly conductive and stable hole transporting layer comprising of N,N'-di(1- naphthyl)-N,N'-diphenylbenzidine $({\alpha}\;-NPD)$ doped with molybdenum oxide $(MoO_3)$. Compared to the reference device, the device with $MoO_3-doped$ hole transporting material exhibits higher conductivity and thermal stability. The temperature dependence of the current-voltage characteristics are studied for various $(MoO_3)$ doping concentration.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.127-129
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• 1999

In this paper, we analogized effective thermal conductivity ($k_{eff}$) and effective heat capacity($pc_{p.eff}$) of insulators and the air in coil portions of linear pulse motor for CEDM(Control Element Drive Mechanism). The errors of simulated results are under 1.6% when compared with experimental results. And we carried out temperature rise of linear pulse motor for CEDM by the experiment.

• 한국전기전자재료학회논문지
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• 제21권2호
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• pp.188-193
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• 2008

Epoxy/Organically Modified Layered Silicate Nanocomposites were prepared by dispersing synthetic layered silicate modified with alkyl ammonium ions. In the dispersing process, the organically modified layered silicate were mixed in epoxy resin with shearing, and aggregation of the silicate were removed by centrifugal separation after mixing epoxy resin and silicates. Micrographs taken by transmission electron microscopy(TEM) indicate that the nanocomposites have a mixed morphology including both parallel silicate layers and exfoliated silicate layers area, As the thermal properties, the glass transition temperature of the nanocomposites was shifted to a higher temperature($+6^{\circ}C$)than pure epoxy. Furthermore, dispersion of OMLS will prevented relative permittivity from increasing at a high temperature above the glass transition temperature.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.17-18
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• 2014

Recently, climate change have increased consumption of building heating and cooling energy. Therefore, various actions to reduce greenhouse gas and energy consumption have been prepared by world developed countries. The energy consumption by buildings approximately reaches 25% of total korea energy consumption. The greatest part in the buildings of the energy consumption is building facade. Especially the outer covering of the building has been made of concrete more than 70%. But a few research projects on concrete comprising more than 70% of outsider of buildings has been tried. This research is structural insulation concrete what improved insulation performance using Micro Form Admixture and Calcined Diatomite Powder and Lightweight Aggregate.