• 전기의세계
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• v.16 no.3
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• pp.21-27
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• 1967

We meet with the fact that a majority of electric machinery have been insulated to the state of solids & liquids or solids & gases, that is, with compound dielectrics. And also we can find voids caused by undesirbble structure, long-used material and so on. When it is discharged in a void or in the parts of gases of insulating material, the insulation of the machinery is gradually and finally destroyed through the effect of ozone, nitrogen-oxide, electronic pulses and so on. So we maybe conculded that it is necessary and important to detected void pulse and void corona in order to prevent sudden break down of electric machinery.

• Journal of the Korean Ceramic Society
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• v.24 no.4
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• pp.392-396
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• 1987

Pure barium titanate was sintered at $1340^{\circ}C$ for 2, 4, 8, 16 hr to control their grain size. The measurements of breakdown strength and partial discharge characteristics were performed under rising AC voltage(60Hz). With increase of sintering time, the average grain size was increased and breakdown strength was slightly decreased. Partial discharge in pores was observed under high voltage, and a model of dielectric break down in barium titanate ceramics is proposed.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.329-334
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• 2001

In this paper, the crack properties of steel fiber reinforced concrete (SFRC) structures for environment by experimental and analytical methods are discussed. The major role played by the steel fiber occurs in the post-cracking zone, in which the fibers bridge across the cracked matrix. Because of its improved ability to break crack, SFRC has better crack properties than that of reinforced concrete (RC). Crack properties are influenced by longitudinal reinforcement ratio, volume and type of steel fiber, strength of concrete.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.419-422
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• 1995

In this paper, we propose two methods for AE source location on the material with unknown AE wave velocity. By this method, we can apply this method to arbitrary material of which properties are not known exactly. Also, in this paper, the mechanism of error generation in both methods are discussed and performances are compared by using computer simulation and experiments which uses a lead break as the AE source on the aluminum plate.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.22
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• pp.113-120
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• 1990

This paper is concerned with marginal analysis in the detailed estimation method. In a broad sense all estimates are marginal estimates in as much as they are concerned with creating changes from a current course of action. Only after a detailed ostinato is made can the engineering realize and exploit the advantages of marginal analysis. Marginal analysis is good tool for nonlinear break-even analysis adapted real world, and much more information and efficiency of CVP(Cost-Volumn-Profit) are provided with marginal analysis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.237-241
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• 2009

Dislocation dipoles were formed in the early stage of deformation of Y-CSZ single crystal at high temperatures. And the dipoles were pinched off to break into dipoles loops by dislocation climb. Dislocation loop annealing was peformed in Y-CSZ single crystal to evaluate the diffusivity of cation which was the rate-controlling ion.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.293-296
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• 1990

In this work, we reviewed AC break-down voltage characteristics in $SF_6$ Gas with spacer under nonuniform field, using the electrode construction of model spacer and simple protrusion. We cleared that breakdown voltage and surface flashover strongly depend on the position of spacer's insert.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.108-110
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• 1994

Decomposition products by crosslinking reaction of PE using Dicumylperoxide(DCP) should influence on the electrical properties in XLPE. This paper studies on Behaviors of Decomposition products and Electrical Treeing ding to Drying condition. We used the Gas Chromatography for Decomposition Gases analysis FT-IR for investigating the behaviors of Decomposition products remained in XLPE Break Down Voltage Tester for Electrical Treeing measurement.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.1
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• pp.75-84
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• 2012

Mechanized operation model and mechanical cultivation technology for winter barley, rye, Italian ryegrass and sudan grass wrap silage production system at the paddy field for cropping system was developed. Also, a series of experiment were performed and lots of data were collected and analyzed to develope mechanical technology, coverage area, and optimum size of the farm (break-even point) for wrap silage production system. The coverage area for winter barley or rye wrap-silage production system is determined around 61.9, 73.4, 77.5, 88.2 ha in the case of drill seeding and different ripening species by tractor power 50, 75, 100, 130 ps, respectably. The break-even point of the farming size is analyzed as 20 ha and its production cost is estimated around 367, 383, 430, 443 won/TDN-kg in the case of winter barley wrap-silage by tractor power 50, 75, 100, 130 ps, respectably. The break-even point of the farming size is analyzed as coverage area and its production cost is estimated around 237, 215 won/TDN-kg in the case of winter barley wrap silage and sudan grass by the tractor power 50, 100 ps, respectably.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.18-21
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• 1986

This study was conducted to clarify the period of induction and awakening of Liatris spicata corm dormancy, and investigated effect of gibberellin treatment on the dormancy break of corm. The results were obtained as follows ; 1. Ratio of sprouting, shooting and rooting were gradually declined after August 30. These ratio showed the lowest to trend on November 14 during experiment and gradually increased after this time. Ratio were excellent as 100% after January 29. 2. Also, average days for sprouting were the longest on the November 14, but it was rapidly declined after January 29. 3. The period of induction and awakening of corm dormancy were late in September and from late January to early February, respectively, in Daegu, Korea. 4. Effects of GA-treatment on the dormancy break of corm were excellent. Especially, its effects on the dormancy break were the deeper in degree of dormancy, the better.