• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.237-240
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• 2002

Fiberglass - reinforced plastic (FRP) can have high breakdown puncture strength and has high mechanical strength. So the research of its dielectric properties have been conducted in liquid nitrogen(L$N_{2}$). In this study, we discussed the characteristics of surface flashover on FRP in L$N_{2}$ for applying it to spacer of a superconducting power equipment. We distinguished four types of surface flashover along solid insulator with arrangement of electrodes and tested the surface flashover voltage of each types of electrode arrangement. The type of a electrode set at the back of the insulator showed the worst dielectric property.

• Progress in Superconductivity and Cryogenics
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• v.6 no.1
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• pp.48-52
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• 2004

Breakdown characteristics of insulator-liquid nitrogen ($LN_2$) composite insulation for resistor type High $T_c$/ superconducting fault current limiter (HTSFCL) under ac and impulse voltage in $LN_2$ has been studied using model electrode systems. Electrodes for model electrode systems were made of SUS 304 contacted fiberglass reinforced plastic (FRP) and Au coated sapphire. The breakdown characteristics of model electrode systems were investigated experimentally for FRP thickness ranging from 1 mm to 5 mm. surface distance ranging from 2.5 mm to 7 mm and electrode gap ranging from 1 to 5 mm. The experimental data suggested that the breakdown voltage of model electrode systems in $LN_2$ is highly dependent on the surface distance, electrode gap as well as on the FRP thickness. Also, we had observed discharge traces and puncture due to high-voltage 60-Hz AC stress.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.3
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• pp.81-88
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• 2013

Recently, energy-saving technology is rapidly becoming a crucial issue for mankind due to the depletion of natural resources. From this perspective, every automobile manufactures are trying to develop light materials and to validate safety with environmental consideration. In this study, we developed clutch connector tube which is the parts of power transferring clutch with light materials to substitude for existing general steel materials. We also verified that the general steel materials can be replaced with nylon, fiberglass, stainless and plastic materials or not. As a result, we verified that the mixture of glass and nylon composite material can substitude the general steel.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.8
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• pp.1303-1308
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• 2017

The underground electricity distributions are significantly increased because of the urbanization accompanied by rural area developments. However, it has also been increased the safety accidents such as an electric shock around the handhole where the underground cables are connected to each other. This paper provides the base materials on the necessity to amend the installation regulation for securing the insulation and structure strength of handholds using the cast iron or fiberglass reinforced plastic. Article 137 in the judgement regulation for the Korea electro-technical regulation which is one of the installation regulations for handhole is amended and announced in 2017 by being based on the materials in this paper. It is expected to continually reduce the electric shock occurrence around handhole by considering the amended installation regulation.

• Geomechanics and Engineering
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• v.12 no.4
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• pp.675-688
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• 2017

The anchor block is a specially designed concrete member intended to withstand pullout or thrust forces from backfill material of an internally stabilized anchored earth retaining wall by passive resistance of soil in front of the block. This study presents small-scale laboratory experimental works to investigate the pullout capacity of a concrete anchor block embedded in air dry sand and located at different distances from yielding boundary wall. The experimental setup consists of a large tank made of fiberglass sheets and steel framing system. A series of tests was carried out in the tank to investigate the load-displacement behavior of anchor block. Experimental results are then compared with the theoretical approaches suggested by different researchers and codes. The appropriate placement of an anchor block and the passive resistance coefficient, which is multiplied by the passive resistance in front of the anchor block to obtain the pullout capacity of the anchor, were also studied.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.10
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• pp.735-741
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• 2007

An axial F.R.P. fan model for cooling tower is developed. The fan is designed using the equations for one dimensional inviscid flow through the fan blade. Fan shape is swept forward with a parabolic function. Calculations of the three dimensional turbulent flow around the fan are carried out to investigate performance of the fan. Data of the total pressure rise and hydraulic efficiency can be obtained for the various setting angles. Calculated values of the total pressure rise and hydraulic efficiency at the design point are less than those of the design specification. The prototype of the F.R.P. fan is made by laminating of the fiberglass and epoxy resins on the mold of fan shape.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.119-123
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• 2002

In this study, we discussed the characteristics of breakdown and surface flashover of FRP in L$N_2$ for applying it to spacer of a superconducting power equipment. Fiberglass reinforced plastic(FRP) has high breakdown puncture strength and has high mechanical strength. So the research of its dielectric properties have been conducted in liquid nitrogen($LN_2$). We measured breakdown voltage of FRP and distinguished four types of surface flashover along solid insulator with arrangement of electrodes and measured the surface flashover voltages of each types of electrode arrangement. The type of a electrode set at the back of the insulator showed the worst dielectric property. The property of surface flashover depending on pressure was tested.

• Transactions of Materials Processing
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• v.4 no.3
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• pp.245-256
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• 1995

SMC(Sheet Molding Compound), a thermoset composite material which consists of unsaturated polyester resin, fiberglass strands, fillers, and various chemical additives for curing agent, has been widely used in fabrication of structural components. The mechanical properties of molded SMS parts are strongly dependent on material flow results during compression molding process, while such flow in molds is affected by material characteristics. For numerical simulation of SMC molding process, estimation of material property of SMC must be accomplished. In this study, flow resistance of SMC was estimated through a simple compression test using a lubricant with grease oil under the constant strain rate condition at various temperatures and the result was compared with other material data available in the literature. The accuracy of the experimentally determined flow resistance was tested by finite element analyses of compression molding of SMC. Simulation results were compared with experimental results under the plane strain condition.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.13-19
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• 2015

본 연구의 목적은 자체 설계 제작한 하이브리드 발사체를 이용하여 대기 중의 미세먼지를 측정하는데 있다. 대기 중의 미세먼지를 측정하기 위한 방법으로는 중량농도법을 이용하였으며, 미세먼지 측정을 위한 포집장치를 자체 제작하였다. 엔진은 5port의 HDPE(High Density Polyethylene)를 연료 그레인으로 사용하였고 $LN_2O$(Liquefied Nitrous Oxide)를 산화제로 사용하였다. 압력, 가속도, GPS 등을 수집하며, 하이브리드 발사체의 동체는 FRP(Fiberglass Reinforced Plastics)로 제작한다. 전체 비행시간은 총 95초로 예상되며. 연소시간은 3초, 고도는 800 m 이다.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1139-1146
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• 2008

Due to the construction technique (or the construction culture) growth in and out of Korea, newly-developed insulation have been continuously released. Furthermore, all legislation and regulation that World follows are gradually becoming unified. (e.g. FTA(Free Trade Agreement) with the United States was contracted, and inevitable FTA contraction with EU and China). In addition, insulation type, with the purpose are becoming unified. Accordingly, KS F 2803 legislated in 1966 about the Domestic Insulation Standard including traditionally used insulation(Rockwool, Fiberglass, Polystrene, Polyurethan, Perlite) has to be amended by considering International Standard and the alternatives. This reference is going to make description for solution of contradiction.