• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.10-11
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• 2014

Energy load of building affected by insulation performance of building's exterior. and insulation system can be classify interior insulation, exterior insulation, sandwich insulation according to install place of insulation. but within interior insulation system, corner wall and the cross outer wall-slab insulation part may occur thermal bridges. And then, within exterior insulation system is more superior insulation performance than interior insulation, but it has difficult to apply, easily broken at high building because of strong wind load. And also difficult to maintenance exterior insulation system. So, in this study, to found requirement performance of cast-in-place sandwich insulation system that is superior insulation performance and easy construction and maintenance. requirement performance of cast-in-place sandwich insulation system is 1) To avoid thermal bridges in the insulation performance, 2) Both sides concrete wall can be composite action in the structural performance. Because of this study, can develops cast-in-place sandwich insulation system and this insulation system contribute to improve insulation performance of apartment-house and high building.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.1
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• pp.131-136
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• 2008

The double-walled steel vessel with powder insulation in the space between the walls is used to minimize heat transfer by radiation and conduction in cryogenic storage tank. The vacuum required the insulation is much less extreme than with high-vacuum or multilayer insulations. The solid supports are used to bear the weight of the inner container. Thermal and structural analysis of the tank have been carried out to study the effect of vacuum and weldment geometry of the internal supports. Heat flux in wall is increased with increasing of thermal conductivity of perlite. Heat flux and stress of support is not affected by weldment geometry.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.590-595
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• 2008

In this paper, the sensitivity analysis was examined about the main factors that compose an air-conditioning system with slab thermal storage by using the analytic solution. Those factors are the insulation performance of floor slab surface, the slab thickness, the heat capacity of floor slab, the air change rate, and the insulation performance of the wall. The slab thickness and heat capacity of floor slab that minimize heating loads was gained by sensitivity analysis. It is became clear that the insulation performance of slab surface, high airtightness and high heat insulation are important design factors in air conditioning system with slab thermal storage.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.4
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• pp.323-329
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• 2012

In this study, a rational procedures for estimation of insulation thickness of a vertical wall for condensation control or personnel protection has been investigated. Design parameters are height of the wall, thermal conductivity, emissivity, and operating temperatures. The results indicated that the surface emissivity plays a very important role in the design of insulation for the purpose of surface temperature control, especially in natural convection situation. radiation heat transfer coefficients for some new insulation material surface, such as elastomers, estimated to be more than 90% of the total surface heat transfer coefficient.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.4
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• pp.469-475
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• 2016

Thermal batteries are primary reserve power sources, which are activated upon the melting of eutectic electrolytes by the ignition of heat sources. Therefore, sufficient thermal insulation is absolutely needed for the stable operation of thermal batteries. Currently, excessive amount of heat sources is being used to compensate the heat loss in the cell stack along with the insertion of metal plates and thermal insulators to reserve heat at the both ends of cell stack. However, there is a possibility that the excessive heat flows into the cell stack, causing a thermal runaway at the early stage of discharge. At the same time, the internal temperature of thermal batteries cannot be maintained above the battery operating temperature at the later stage of discharge because of the insufficient insulation. Therefore, the effects of Phase Changing Material(PCM) plates were demonstrated in this study, which can replace the metal and insulating plates, to improve the thermal insulation performance and safety of thermal batteries.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.585-591
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• 2021

Liquefied hydrogen have advantage which reduces the volume by about 800 times or more compared to hydrogen gas, so it is possible to increase the storage density. However, liquefied hydrogen produced by cryogenic cooling of 20 K or less at normal pressure has a problem of maximizing the insulation effect that blocks heat introduced from the outside. Representative insulation technologies include vacuum insulation and multi-layer insulation materials and in general, heat blocking is attempted by combining insulation technologies. Therefore, in this study, the pressure of the internal vacuum layer was changed to 10^-1, 10^-2, 10^-3 and 10^-4 Torr to confirm the thermal insulation performance of the vacuum jacket valve for transporting liquefied hydrogen. As a result, it was confirmed that the insulation performance improved as the degree of vacuum increased.

• Clean Technology
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• v.22 no.1
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• pp.45-52
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• 2016

This study reports on the modeling and simulation of heat transfer in packaging boxes used for vaccine shipping. Both water and n-tetradecane are used as primary insulation materials inside a multi-slab system. The one-dimensional model, which is a spherical model using a radius equivalent to the rectangular geometry of container, is applied in this study. N-tetradecane with low thermal diffusivity and proper phase transition temperature exhibits higher heat transfer resistance during both heating and cooling processes compared to water. Thus, n-tetradecane is a better candidate as an insulating material for packaging containers for vaccine shipping. Furthermore, the developed method can also become a rapid and economic tool for screening appropriate phase change materials used as insulation materials with suitable properties in logistics applications.

• Journal of the Semiconductor & Display Technology
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• v.18 no.2
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• pp.29-31
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• 2019

The ZTO/p-Si thin film was produced and investigated for tunneling phenomena caused by the interface characteristics of the depletion layer. ZTO thin film was deposited and heat treated to produce barrier potentials by the depletion layer. The negative resistance characteristics were shown in the thin film of ZTO heat treated at $100^{\circ}C$, and the insulation properties were the best. Current decreased in the negative voltage direction by nonlinear show key characteristics, and current decreased in tunneling phenomenon by negative resistance in the positive voltage direction. Heat treated at $100^{\circ}C$, the ZTO thin film has increased barrier potential in the areas of the depletion layer and therefore the current has increased rapidly. The current has decreased again as we go beyond the depletion layer. Therefore, tunneling can be seen to make insulation better. In the ZTO thin film heat treated at $70^{\circ}C$ without tunneling, leakage current occurred as current increased at positive voltage. Therefore, tunneling effects by negative resistance were found to enhance insulation properties electrically.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.785-790
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• 2001

Linear motors can drive a linear motion without intermediate gears, screws or crank shafts. Linear motors can successfully replace ball lead screw in machine tools, because they have a high velocity, acceleration and good positioning accuracy. On the other hand, linear motors emit large amounts of heat and have low efficiency. In this paper, heat sources of a synchronous linear motor with high velocity and force are measured and analyzed. To improve the thermal stiffness of the linear motor, an insulation layer with low thermal conductivity is inserted between cooler and machine table. Some effects of the insulation layer are presented.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1288-1289
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• 2006

Innovative SMC with low iron loss was made from iron powders with evaporated MgO insulation coating. The coating had greater heat-resistance than conventional phosphatic insulation coating, which enabled stress relieving annealing at higher temperature. Magnetic properties of toroidal samples (OD35mm,ID25mm, t5) were examined. The iron loss at 50Hz for Bm = 1.5T was lower 50% of conventional SMC and was almost the same with silicon iron laminations(t0.35). It became clear that MgO insulation coating has enough heat resistance and adhesiveness to powdersurface to obtain innovative SMC with low iron loss.