• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.405-407
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• 2006

The power system analysis based on the accurate impedance of the individual underground cable, which is the inter connected to a large power system, is required. A study on calculation method of impedance allowable current for underground cables. furthermore, various methods of bonding and earthing the sheath have been used for the purpose of eliminating or reducing the sheath losses. the effectes of bonding and earthing must be includied in impedances. therefore, the subject of predicting thermal performance of soil and cable systems has been received increasing attension. for these problems, this paper describes a general formulation of impedance that is based on the effect of crossbonding and earthing of the sheath on the 66kV, 132kV and 220kV underground cable systems. also the work is presented, for calculating the temperature rise of power cable and soil.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.500-502
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• 2002

Receltly, Underground transmission system is getting increased. Therefore the design of grounding system becomes very important to discharge overcurrent of lightning and fault through earth and reduce sheath induced voltage and sheath circulation current. This paper describes fault current distribution ratio for grounding line with grounding types of normal joint box and sheath grounding resistor at line-to-ground fault of cable.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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• pp.156-158
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• 2000

As we are industrialized lately, power capacity is increased in the city urban areas. So the application of underground transmission line is largely expended. In this paper, we analysis the induction voltage on the sheath of 1,200[$mm^2$] OF underground cable being used 154kV underground transmission line. If the current on the cable conductor is 300[A], circulation current is induced the maximum 100[A] on the cable sheath.

• 전기학회논문지
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• 제64권2호
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• pp.240-246
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• 2015

Length of most underground power cable in home is not so long. Therefore it is operated without transposition due to low unbalanced ratio. However, if cable length is long, line constant of each cable will be different. Different line constant can induce unbalanced voltage and current of sheath. Also it can induce several induced interference. This paper describes the effectiveness of transposition through sheath component analysis on transposition and untransposition of cable conductor. Especially sheath current and induced voltage are analyzed and compared in case of transposition and untransposition. EMTP is used for modeling and analysis.

• 대한후두음성언어의학회지
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• 제29권1호
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• pp.41-43
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• 2018

"Saber-sheath" trachea is a deformity of lower cervical or intrathoracic trachea. The configuration of the deformity is marked coronal narrowing associated with sagittal widening. This deformity is associated with chronic obstructive pulmonary disease. We report a case of patient with saber-sheath who underwent total laryngectomy. Although the patient had no tracheal collapse after the total laryngectomy, crusted discharge was increased. Diagnosis of the saber-sheath trachea, possible causes, and clinical implications are discussed.

• 한국응용곤충학회지
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• 제19권4호
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• pp.234-238
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• 1980

벼 도열병균의 엽초내균사신전도와 잎표피세포내의 침입율과는 기주가 접종전 같은 온도조건하에서 자랐을 경우 고도의 유의성이 있었으며 또한 이들 두 요인간에는 정의 상관관계가 있었다.

• Plant Resources
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• 제5권3호
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• pp.176-180
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• 2002

This study was conducted to develop the clonal propagation technique through in vitro culture using by leaf sheath explants of Phalaenopsis grown in vitro. The highest frequency of protocorm-like body (PLB) formation was obtained when explants of leaf sheath were cultured on VW medium containing 30g/L sucrose, 500 mg/L activated charcoal, 150 mVL coconut water, 1 mg/L NAA, 1 mg/L 2ip and 2.5 g/L gelrite. The PLB formation rate of VW medium was highest followed by modified Hyponex medium, and lowest in MS medium. Plantlets induced from PLBs transferred to plastic pots including spagnum moss were well developed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.294-295
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• 2015

Many unbalanced factors of underground transmission power cable, such as burying types and the length difference of the cable between each minor section, etc will cause the impedance unbalance and excessive circulating current between cables. So this paper presents the analysis of sheath circulating current in accordance with the distance between the center conductors and phase arrangement. ground resistance value changes on 154kV transmission system. Based on these simulation results, this paper will contribute to the reduction method of sheath circulation current.

• Progress in Superconductivity
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• 제1권2호
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• pp.141-145
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• 2000

Different twist pitches of multi filamentary BSCCO 2223 tapes using high resistivity sheath were fabricated to investigate the effect of twist pitches on the microstructure and critical current property. A conductor with a high resitstivity matrix is possible to allow larger twist pitch for reducing ac losses and reduce eddy current losses simultaneously. The $J_{ct}$ values of 10 mm and 5 mm twisted tapes drop faster than that of untwisted and 20 mm twisted tapes under increasing magneticfield, especially in low field regime (0 $\sim$ 0.03 T). It suggests that weak links in the former are more serious than in the latter, which is in accordance with the microstructure analysis.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.65-67
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• 2003

The critical current of Bi-2223/Ag HTS wire could be improved by the second phase modification pre-treatment (SPMT). On the other hand, the pre-treatment conditions are possible to affect to the degradation of silver alloy sheath, such as brittleness. Chlorine was detected at the outer sheath of wire by Auger observation, we also have tried to search new pre-treatment conditions that do not affect the degradation of silver sheath but, improve the critical current of the wire.