• Nuclear Engineering and Technology
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• 제27권6호
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• pp.811-824
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• 1995

CANDU 핵연료봉의 휨 열적 휨 멘트와 수력학적 견인력 및 기계적 하중에 기인하는 휨 모멘트에 의하여 일어난다. 여기서, 연료봉 휨은 연료봉 축방향 중심선으로부터의 측면 처짐으로 정의한다. 본 논문에서는 연료봉 축방향 중심선에 대한 비대칭 온도불포에 의해 핵연료 피복관 자체와 피복관과 소결체의 상호작용 부위에서 발생하는 열적 휨만을 취급한다. 이를 위해 1).소결체와 피복관사이의 기계적 상호작용을 무시한 조건에서의 핵연료 피복관의 휨과 2) 소결체와 피복관의 온도 변화에 기인하여 발생하는 소결체와 피복관 사이의 기계적 상호작용을 고려한 조건에서의 연료봉 휨을 혼합 고려하고, 각각에서 피복관의 비대칭 온도분포가 (i) 냉각재의 불완전한 혼합에 따른 비균질 냉각재 온도, (ii) 핵연료 피복관과 냉각재 사이의 비균질한 열전달 계수, (iii) 핵연료내 반경 방향으로의 중성자속 감쇄에 의한 비대칭 열 발생 등의 복합적효과에 의해 발생되는 것으로 고려하여 피복관의 대칭온도 분포까지 포함 할 수 있는 열적 휨의 일반적 해석 공식을 제시하였다. 본 휨 공식에 사용되는 모든 변수에 대한 민감도 분석을 통해, 핵연료봉 길이, 피복관 내경, 냉각재 평균 온도 및 변화 인자, 소결체 -피복관 기계적 상호 작용 인자, 중성자속 감쇄 인자, 핵연료 열팽창 계수, 피복관-냉각재 열전도 계수 등의 변화가 피복관 두께, 피복관-냉각재 열전달 계수, 피복관 열팽창 계수, 핵연료-피복관 열전달 계수 등의 변화보다 핵연료봉의 열적 휨에 상대적으로 더욱 영향을 미치는 것으로 밝혀졌다.

• Archives of Plastic Surgery
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• 제37권1호
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• pp.67-70
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• 2010

Purpose: Nerve sheath myxoma is a rare cutaneous neoplasm originating from the peripheral nerve sheath and divided into three groups : myxoid, cellular and mixed type. There is a controversy on it's origin whether schwannian cell or perineurial differentiation, or anything else. Myxoid nerve sheath myxoma is asymptomatic, soft, papule or nodule in middle-age adults. We report a case of myxoid nerve sheath myxoma on the fingertip. Methods: A 53-year-old woman presented with a painful, $0.4{\times}0.4{\times}0.6\;cm $sized, corn shaped nodule on the left 3rd fingertip. We put into surgical excision and studied it by histopathologically and specific immnohistochemical stain. Results: The tumor has well defined nodules separated by thin fibrous connective tissue with abundant myxoid stroma and were positively stainded for S-100 protein, NSE and GFAP. After surgical treatment it was healed without recurrence. Conclusion: Nerve sheath myxoma is rare neoplasm and located mainly on face, but very rarely on the fingertip. We report a case of painful myxoid nerve sheath myxoma located on the 3rd fingertip.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.470-470
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• 2010

Negative ions are generated in fusion edge plasmas, material processing plasmas, ionospheric plasmas. Analytic formulas for the deduction of the absolute density of negative ions was given by using the current-voltage(IV) characteristics of two electric probes at two different pressures [1], and negative ion density has been measured by one electric probe using the current-voltage characteristics of three different pressures [2]. Ratios of ion and electron saturation currents and electron temperatures and sheath areas of different pressures are usually incorporated into two equations with two unknowns for the negative ion density. In the previous publications, the sheath factor(sheath area, sheath density, sheath velocity) and effective masses of background ions with different pressures are qualitatively incorporated for the deduction of negative density. In this presentation, the quantitative and detailed relation of negative ion density with sheath factor and effective masses are going to be given. The effect of these parameters on the change of IV characteristics will be addressed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.449-451
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• 2002

Sheath circulating current rises from the change of sheath mutual impedance which is caused by imbalanced cable system, and different section length between joint boxes. However, mixed burying typo and imbalance section length take many parts of main reasons of sheath circulating current increment in domestic underground transmission power cables. Therefore, the increment reason and variation characteristics of sheath circulating current is analysed with simulation using EMTP/ATPDraw and measuring data of practical cable system which has a problem of exceeding sheath circulating current in this paper.

• 한국표면공학회지
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• 제47권1호
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• pp.53-56
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• 2014

I-V characteristics of a cylindrical target in an ECR plasma were studied for sheath spatial evolutions when the target was pulsed biased to a high negative potential. The magnetic field effects on sheath thickness and sheath boundary speed were investigated by comparison between the experimental results and the theoretical results using the Child-Langmuir sheath model. The results showed that the magnetic field suppressed electron motion away from the target so that sheath thickness and sheath boundary speed decreased.

• 한국분말재료학회지
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• 제9권3호
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• pp.153-160
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• 2002

A nitrogen gas atomized aluminum powder was consolidated by powder-in sheath rolling method. A pure aluminum tube with outer diameter of 12 mm and wall thickness of 1mm was used as a sheath. The aluminum tube filled with the aluminum powder, first, was cold-rolled to the thickness of 6mm for performing, and then consolidated by the cold rolling and/or subsequent hot rolling at 360, 460 and $560^{\circ}C$. The aluminum powder compact fabricated by the sheath rolling showed high relative density more than 0.96 at any rolling conditions. The 0.2% proof stress increased with increasing hot rolling reduction and hot rolling temperature. Tensile strength was hardly affected by change in the hot rolling reduction, whereas it decreased with increasing hot rolling temperature. The powder compact showed the large elongation when cold rolling or hot rolling reduction was large. It was found that the sheath rolling was an effective method for consolidation of aluminum powder.

• The Korean Journal of Pain
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• 제26권2호
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• pp.160-163
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• 2013

Malignant peripheral nerve sheath tumors (MPNSTs) are very rare sarcomas derived from various cells in the peripheral nerve sheath. Malignant peripheral nerve sheath tumors have a known association with neurofibromatosis type 1. Diagnosis of MPNSTs is difficult in patients with chronic pain, when MPNST occurs at an overlapping area of chronic pain. Therefore, the diagnosis can be missed unless clinicians pay attention to the possibility of this disease. Here in, we report a case of concurrent malignant peripheral nerve sheath tumor with complex regional pain syndrome type 1. A 44-year female patient, who was diagnosed with complex regional pain syndrome (CRPS) type 1 in her left ankle, visited our clinic because of aggravated pain. The cause of the aggravated pain was revealed as concurrent MPNST in the left common peroneal nerve territory, which overlapped the site of pain from CRPS.

• Current Research on Agriculture and Life Sciences
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• 제21권
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• pp.31-37
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• 2003

나리속(屬) 식물의 엽초는 품종에 따라 엽위별 형태와 숫자가 큰 차이를 보여 품종별로 식재깊이에 따른 엽초수를 조사하고, 엽초를 제거한 후 생육 반응을 알아보았다. 품종별 엽초는 0cm로 식재한 경우 'Jolanda'는 6매엽, 'Dream Land'는 5매엽과 'Casablanca'는 11매엽으로, 6cm로 식재한 경우 'Jolanda'는 6매엽, 'Dream Land'는 5매엽과 'Casablanca'는 14매엽으로 밝혀져 'Jolanda'와 'Dream Land'는 식재깊이에 따라 엽초수의 차이가 없었으나 'Casablanca'는 6cm로 식재한 것이 0cm로 식재한 것에 비해 엽초가 3장이 더 많아졌다, 한편 엽초를 제거함으로써 'Le Reve'와 'Casablanca' 두 품종 모두 초장이 작아졌으며 stem root의 생육이 나빠졌다. basal root의 생육과 꽃수는 품종별로 다른 양상을 나타냈으며 줄기 직경, 개화소요일수와 꽃의 크기는 차이가 없었다.

• Current Research on Agriculture and Life Sciences
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• 제21권
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• pp.17-21
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• 2003

글라디올러스의 생육에 있어 엽초의 역할을 알아보기 위해 제거시기와 제거수를 달리하여 엽초제거 한 후 생육반응을 조사한 결과, 생육초기의 광조건에 관계없이 엽초를 모두 제거함으로써 화경장과 화수장이 짧아졌고 개화수도 적어졌으며 특히 제거시기가 빠를수록 생육이 현저하게 저조해졌다. 그러나 엽초제거에 따른 개화소요일수는 차이를 보이지 않았다. 엽초를 엽위별로 제거한 처리구에서 엽초 1, 2 및 3매를 제거한 것은 생육 차이를 보이지 않았으나 글라디올러스의 초장 생장에 비례적으로 자라난 4번째 엽초를 포함하여 제거한 엽초 4매 제거구에서 타 처리구에 비해 화경장이 25cm이상 작아졌으며 화수장도 짧아지고 개화수도 적어졌다. 또한 줄기기부도 비정상적으로 굵어졌다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.551-554
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• 2004

Bi-2223 HTS tapes are used widely for application of superconducting power systems. However there are need the properties of high strength and low AC loss. Two kinds of Bi-2223 HTS tapes with different Ag sheath were used to know the effect of sheath alloying for the strength and the resistivity. The workability and reaction degree of superconducting phase at Bi-2223 HTS tapes were investigated. We designed conventional type-Ag/alloy and double sheathed mono filament type-Ag/alloy/alloy in order to increase the strength and resistivity of matrix in Bi-2223 HTS tapes. The effect of axial strain and thermal cycling on the critical current was investigated for the Bi-2223 HTS tapes. Because the workability of double sheath Bi-2223 HTS tape was lower than one sheath Bi-2223 HTS tape, it was need additional softening treatment. Bi-2223 formation reaction was decreased by Ag alloy matrix during sintering process. Two kinds of Bi-2223/Ag tapes with different Ag sheath were used to know the effect of sheath alloying for the tensile strain. Critical current is drastically decreased for Ag/alloy and Ag/alloy/alloy sheathed tapes at tensile strain above 0.24 % and 0.34 %, respectively. This result showed that mechanical strength was increased over than 40 % by introduce double sheath at mono filament stage.