• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.547-549
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• 2000

Silicone insulators have many advantages over porcelain insulators. Especially silicone insulators have good characteristics of impact hardness, surface insulation, ease of processing, mass productivity and don't have risk of bombardment and vandalism. Recently insulation part made by silicone are becoming widely used. In this paper we introduce the development of Sealing End for 132kV XLPE cable with silicone composite hollow insulator and the adoption of it to a actual transmission line in abroad. This paper contains of design procedure, structure, electrical performance of it.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.6
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• pp.316-323
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• 2004

HTS transformer is one of the most promising devices to supply enough electric energy for quick increase consumption. However, for practical design of the HTS transformer, it is necessary to establish the research on breakdown, V-t characteristics, degradation, and so on. In this paper, we discussed breakdown characteristics and V-t characteristics of polyimide/L$N_2$ and glass fiber reinforced plastic/$LN_2$ composite insulations. These composite insulations have been used as turn-to-turn and layer-to-layer insulations for HTS transformer respectively, Moreover, we investigated the degradation of these insulation samples after breakdown using microscope and SEM photograph.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.9-12
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• 1994

Epoxy-Ceramic Composite have good insulating, therma1 and mechanical properties, so it is studied actively on this material. In this thesis, we made a composite material b)\ulcorner filling Epoxy Resin with ceramics treated with Sillane Coupling Agent and studied dielectric and insulating characteristics according to treatment density of Sillane Coupling Agent and weight percent of filler. As a result, loss tangent increase and electrical breakdown voltage decrease according to increasing treatment density of sillane coupling agent because Interface matching between matrix and filler is not good. The best treatment density of sillane coupling agent is 0.5% water solution, in this density the best interface matching is achieved so good dielectric and insulation characteristics are shown. Dielectric and insulation characteristics according to weight percent of filler are best at 25wt.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.397-403
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• 2016

As a building energy saving standard strengthened, The number of building installed external thermal insulation composite system(ETICS) using EPS insulation increased. But frequent fire accident in the buildings installed EIFS using EPS led to strengthening of building fire safety regulation. This study is for fire property of EPS ETICS reinforced with noncombustible calcium silicate-based mineral insulation as a fire spread prevention structure(FSPS). Fire test for large scale wall by ISO 13785-2 was applied and results showed EPS EIFS with FSPS got 3~8 times superior fire safety than normal EIFS by visual investigation. Temperature and heat flux measurement results, which data of upside of specimen were lower than downside, also supported fire safety of EIFS with FSPS.

• Progress in Superconductivity and Cryogenics
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• v.11 no.2
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• pp.25-28
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• 2009

A 154kV class high-temperature superconducting (HTS) power cable system is developing in Korea. For insulation design of this cable, it is important that study on cryogenic electrical insulation design to develop the cold dielectric type HTS cable because the cable is operated under the high voltage environment in cryogenic temperature. Therefore, this paper describes a design method for the electrical insulation layer of the cold dielectric type HTS cable adopting the partial discharge-free design under ac stress, based on the experimental results such a ac breakdown strength, partial discharge inception stress, $V_{ac}$-t characteristics, $V_{imp}$-n characteristics, and impulse breakdown strength of liquid nitrogen/laminated polypropylene paper (LPP) composite insulation system in which the mini-model cable is immersed into pressurized liquid nitrogen.

• Composites Research
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• v.31 no.5
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• pp.227-237
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• 2018

In this paper, the design application for the lightweight and insulation of the manipulator of the mobile welding robot for the closed/narrow space is presented. A variety of robotic platforms have been developed for weld-worker using a welding robot outside a workpiece for welding work in a complex and narrow space such as a ship or an offshore plant. Normally, The development process of robots consists of machine development, electronic device development, control algorithm development and integration verification considering application environment and requirements. In order to develop the robustness of the welding robot, the lightweight design of the robot manipulator considering the environmental conditions was performed in the basic design of the robot platform. Also, The results of the robot selection and validation, analysis and testing for the insulation performance and cooling performance and the results of the research are shown.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.6
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• pp.642-650
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• 2016

One of the most feasible solution for reducing the excessive energy consumption and carbon dioxide emission is usage of more efficient fuel such as hydrogen. As is well known, there are three viable technologies for storing hydrogen fuel: compressed gas, metal hydride absorption, and cryogenic liquid. In these technologies, the storage for liquid hydrogen has better energy density by weight than other storage methods. However, the cryogenic liquid storage has a significant disadvantage of boiling losses. That is, high performance of thermal insulation systems must be studied for reducing the boiling losses. This paper presents an experimental study on the effective thermal conductivities of the composite layered insulation with aerogel blankets($Cryogel^{(R)}$ Z and $Pyrogel^{(R)}$ XT-E) and Multi-layer insulation(MLI). The aerogel blankets are known as high porous materials and the good insulators within a soft vacuum range($10^{-3}{\sim}1$ Torr). Also, MLI is known as the best insulator within a high vacuum range(<$10^{-6}{\sim}10^{-3}$ Torr). A vertical axial cryogenic experimental apparatus was designed to investigate the thermal performance of the composite layered insulators under cryogenic conditions as well as consist of a cold mass tank, a heat absorber, annular vacuum space, and an insulators space. The composite insulators were laminated in the insulator space that height was 50 mm. In this study, the effective thermal conductivities of the materials were evaluated by measuring boil-off rate of liquid nitrogen and liquid argon in the cold mass tank.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.107-115
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• 1998

This paper deals with the study on injection with EPDM(Ethylene propylene dien ter polymer) the gap which narrow, long, and tubular between an ablative composite tube and a steel motor case. Small size motor assembly was designed and manufactured for man-portable air defense propulsion system. Motor assembly is consisted with steel tube, ablative composite tube and insulation rubber. Ablative composite tube was made of carbon/phenolic prepreg by rolling process and insulation rubber was made of EPDM by TPM(Trans-power molding) process. To select the insulation rubber material, we tested ablative insulation property and degradation property at first and we tested fluidity, adhesive property and hardness of EPDM rubber. Finally we designed TPM process to manufacture motor case assembly and the motor case assembly was examined by non-destructive test(X-ray).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.204-205
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• 2006

In the response to the demand for electrical energy, much effort aimed to develop and commercialize high temperature superconducting (HTS) power equipments has been made around the world. In Korea, companies and universities are developing a power distribution and transmission class HTS transformer that is one of the 21st century superconducting frontier projects. The composite winding of transmission class HTS transformer is concentrically arranged H1-L-H2 from center. H1 is continuous disk type, L is layer type and H3 is continuous disk type. For the development of transmission HTS transformer with composite winding, the cryogenic insulation technology should be established. We have been analyzed insulation composition and investigated electrical characteristics such as breakdown of $LN_2$, barrier, kapton films, surface flashover on FRP in $LN_2$. We are going to compare with measured each value and apply the value to most suitable insulating design of the HTS transformer.

• Journal of Powder Materials
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• v.30 no.4
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• pp.356-362
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• 2023

Inorganic-organic composites find extensive application in various fields, including electronic devices and light-emitting diodes. Notably, encapsulation technologies are employed to shield electronic devices (such as printed circuit boards and batteries) from stress and moisture exposure while maintaining electrical insulation. Polymer composites can be used as encapsulation materials because of their controllable mechanical and electrical properties. In this study, we propose a polymer composite that provides good electrical insulation and enhanced mechanical properties. This is achieved by using aluminum borate nanowhiskers (ABOw), which are fabricated using a facile synthesis method. The ABOw fillers are created via a hydrothermal method using aluminum chloride and boric acid. We confirm that the synthesis occurs in various morphologies based on the molar ratio. Specifically, nanowhiskers are synthesized at a molar ratio of 1:3 and used as fillers in the composite. The fabricated ABOw/epoxy composites exhibit a 48.5% enhancement in mechanical properties, similar to those of pure epoxy, while maintaining good electrical insulation.