• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.274-277
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• 1996

This paper describes the realization of the full-color to the degree of nearest white light by compounding high brightness Red, Green and Blue LEDs with appropriate proportional index. Once these three colors; red, green and blue are mixed, they are genearlly additive mixing and produce white light color contrasted to negative mixing. The luminous efficiency is defined as the product of the efficiency(lm/w), which indicates the degree of perceptual response by the human eye to unit energy(W) of light emitted by an active display devises and as the conversion efficiency of the device from electric power consumed to optical energy produced. We will deduce the each number of LEDs theoretically and design several shapes of LED displays for the full-color. Finally theoretical predictions will be compared with the measured data with different type of display designs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.11
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• pp.1001-1007
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• 2003

The silicone fluids have been generally used as processing agent in silicone rubber(SIR) compounding. The addition of hydroxy silicone (HS) fluids to SIR for insulator housing material is required to meet the good electrical performance and the good processability. In this study, SIR with HS fluids was evaluated to investigate how the kinds of them affect insulation properties. The contact angle of the virgin sample of 40-HS SIR was low and its recovery rate was also slow. The recovery rate of 50-HS SIR was the highest being decreased with the viscosity increase of HS fluids. The tracking resistances and the corona aging resistance of 70-HS SIR and 1,040-HS SIR were excellent Tracking resistance depended largely on heat resistance of silicone fluids. But arc resistance didn't depend merely on the kind of silicone fluids.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.206-209
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• 2002

The purpose of this research was to find influence of compounding materials on electrical properties of silicone rubber such as tracking characteristic. The tracking characteristic was tested through controlling the ATH, a widely use anti-tracking agent. Regarding the particle size and coupling agent of ATH, compound silicone rubber with ATH of coupling agent and larger diameter showed better anti-tracking properties. It can be included that ATH of coupling agent use vinyl silane, dispose of tracking characteristic was achieve excellant results.

• Transactions on Electrical and Electronic Materials
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• v.10 no.1
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• pp.9-15
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• 2009

There is a growing demand for a high voltage silicone rubber composite with high mechanical property and high electrical property. The effect of modified cross-linking agent on the mechanical, electrical properties, and short-circuit test performance of silicone rubber insulators have been investigated. To use base polymer, the various silicone polymers were prepared by the equilibrium polymerization. Aluminum trihydrate surface was treated by vinyl silane. Liquid silicone rubber nanocomposite was prepared from the compounding of VPMPS, HPDMS, catalyst, and alumina trihydrate modified with 1,3,5-trivinyl-l,3,5-trimethylcyclotrisiloxane. The mechanical property and electrical property for insulation materials were measured, indicating the high tensile strength and the good short-circuit property.

• Elastomers and Composites
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• v.51 no.1
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• pp.38-42
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• 2016

For improving the heat loss of a refrigerator around door gasket, it is very important to reduce the amount of rubber magnet used, of which thermal conductivity is much higher than the plastics, and enhancing the magnetic properties of rubber magnet itself is crucial for this. In the present study, therefore, a relationship between the optimum conditions of rubber magnet fabrication process and raw material compositions in the ferrite powder/CPE binder compounds was investigated for finding a way to enhance the magnetic properties of rubber magnet. Magnetic attraction forces of a sample rubber magnet was measured as function of distance, and thermal properties of the sample ferrite powder/CPE binder compound were analyzed with TG/DTA thermal analyzer. As a results, a rubber magnet strip with enhanced magnetic properties was expected to be fabricated, of which raw material compound was prepared by compounding with higher ferrite magnetic powder concentration.

• Elastomers and Composites
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• v.25 no.2
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• pp.97-102
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• 1990

Linear viscoelastic properties of 11 types of EPDM and 1 type of EPM rubbers have been measured at $210^{\circ}C$, using a RDS(Rheometrics dynamic spectrometer). The data base, i.e., complex viscosity, storage modulus, loss modulus, loss tangent and relaxation spectrum of the sample should be useful for rubber blending and compounding.

• Elastomers and Composites
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• v.4 no.1
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• pp.83-88
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• 1969

As a part of a series of previous studies, physical properties of various portions of a tire made of NR-Syn. R bloods were studied. 1. It was found, in general, most effective for tire tread when 50 parts of HAF black was blended with NR and Syn. R with a ratio of 70/30. 2. It was found that the use of SBR 1712 has an advantage in price, easy processing and physical properties than other synthetic rubber. 3. A technical compounding of various portions of a tire has to be determined for optimum cure conditions.

• Elastomers and Composites
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• v.4 no.1
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• pp.89-93
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• 1969

1. Physical properties of various nylon cords in a tire, both of home and foreign products are studied. The experimental data for home nylon cords appeared to be quite satisfactory for use in a tire compared with foreign nylon cords with respect to its tenacity, elongation, shrinkage and contraction. 2. Excellent results have been obtained with 50 phr carbon in butyl-carbon compounding.

• Elastomers and Composites
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• v.27 no.4
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• pp.281-288
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• 1992

The purpose for this study is to examine the vulcanization characteristics, especially the damping, elastic modulus and viscous modulus properties of filler 50phr filled NR compounds and to find out the compounds which can be used as damping materials in industry. For this study, compounds were prepared with filler filled compounding formula. Their vulcanization characteristics, elastic modulus, viscous modulus and damping properties were examined by mean of the rheometrics dynamic spectrometer. The results of this study can be summarized as follows. 1. The elastic modulus values of the maxium under the condition of 1Hz frequency, showed the order as follows, $HAF>Silica>FEF>GPF>SRF>Clay>CaCO_3\;coated>CaCO_3$. 2. The damping values of the maxium under the condition of 1Hz frequency, showed the order as follows $Silica>HAF>FEF>GPF>SRF>Clay>CaCO_3\;coated>CaCO_3$.

• The Korean Journal of Financial Management
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• v.25 no.4
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• pp.145-182
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• 2008

As the life expectancy increases resulting in the aged society, the post-retirement life became one of the most important concerns of people. The long-term investment vehicles such as retirement savings and pension plans have been introduced to meet such demand of society. This paper examines the impact of asset allocation strategies on the long-term investment performance. Because of the unusually long investment horizon and the compounding effect, a suboptimal asset mix in a retirement plan can be a very costly and irreversible mistake. Instead of relying on anecdotal evidence to evaluate the merits of different allocation strategies, this paper performs various tests including stochastic dominance tests using both actual data and Monte Carlo simulated data that best fit the historical experience. The results indicate 1) the long-term investments perform better than the short-term investments, 2) the optimal asset allocation strategy for the long-term investments should be highly equity dominated.