• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 초전도 자성체
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• pp.25-28
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• 2002

Contact type Ic measurement system is needed to measure Ic continuously for long Bi-2223 tapes. Voltage and current terminals were designed several shapes for 4-probe method Ic measurement. Voltage terminals were made with brass and current terminals were made with Cu. We used 2 kinds of Bi-2223 tapes with different strength. When we measured Ic of Bi-2223 tape with Ag-Mg sheath, The proper weight was 0.3 kg and sharp pin type was better. according to voltage terminal shape and load. In case of Bi-2223 tape with Ag-Mn sheath, the proper terminal weight was 4 kg and sharp pin type was bad. It was possible to make continuous contact type Ic measurement system because We could get proper data - terminal shapes and loads - through these experiments.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 초전도 자성체 연구회
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• pp.25-29
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• 2003

Pre-treatment of Bi-2223/Ag tapes has been investigated to improve the superconducting property and grain alignment. However, rolling deformability of Bi-2223/Ag wires was degraded by the breakage of Ag alloy sheath after pre-treatment. Various pre-treatment conditions were tried to prevent the problem of sliver sheath and improve the superconducting property of Bi-2223/Ag tapes. Filament precursor of Bi-2223/Ag tapes was modified to be textured easily during main sintering by the optimum pre-treatment with low oxygen pressure and up to $800^{\circ}C$. Critical current was also increased up to 20% than that of no pre-treated tape.

• 한국광학회지
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• 제1권1호
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• pp.65-72
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• 1990

최대 10kJ의 에너지를 공급할 수 있는 Mather형 플라즈마 집속장치를 설계, 제작하였다. 이 DPF 장치의 전기 방전 특성을 알기 위해 Rogowski 코일을 제작하고 방전전류, 전압을 측정하여 본 system 의 저항과 인덕턴스는 각각 $20m\Omega과 0.2{\mu}H로 밝혀졌다. 플라즈마 전류 sheath의 이동속도는 충전개스 압력과 전압에 따라 $P^{-0.25}\timesV^{0.38}$의 함수로 비례하며 집속된 플라즈마의 크기는 직경 3mm, 길이 17mm로 밝혀졌다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.3-6
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• 2004

In this paper, we studied on permissible current of unperfected earthing for cross-bond system. The factors of unperfected earth were jacket damage, cross-bonding mistake, arrestor damage, effect of other circuit but we only studied permissible current of arrestor or jacket damage. In the result, we earned that permissible current of normal 154[[kV]] CV $1C{\times}400SQMM$ cable is 760[A] but current of unperfected earthing cable is 76[A], unperfected earthing confirmed that accident of underground cable could occur. So, we could confirmed that Earthing resistance of unperfected earthing need to limit.

• 대한족부족관절학회지
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• 제9권2호
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• pp.213-215
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• 2005

Tarsal tunnel syndrome caused by space occupying lesion is unusual but it rarely occur by ganglion which is presented below the flexor retinaculum due to compression neuropathy of posterior tibial nerve and its branches. The object of the current study is to report our experience of surgical treatment about tarsal tunnel syndrome caused by the ganglion of flexor digitorum longus tendon sheath and multifocal myxoid degeneration of medial plantar nerve with a review of the literatures.

• 연구논문집
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• 통권27호
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• pp.175-181
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• 1997

Superconducting joints between Bi-2223/Ag tapes are fabricated by a press & reaction anneal and a multiple press & anneal. The silver sheath was mechanically or chemically removed from one side of each tape without altering the superconducting core. The exposed superconducting core of the two tapes were brought into contact and pressed so as to form a lap joint. The joined tapes were then subjected to a series of different thermomechanical treatments to achieve optimum heat treatment condition. The result from transport measurements shows that critical current ($I_c$) transmitting through joined area reaches 9A, approximately 60% of the current capacity of the tapes themselves. The critical current through joined area was improved by repeated press and reaction annealing. Measurements of the current-voltage relationship were made with several configuration of the voltage probes to characterize the critical current variation and I-V curve along the joint. Also discussed are microstructural aspects of the superconducting joint.

• 한국초전도ㆍ저온공학회논문지
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• 제3권1호
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• pp.6-10
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• 2001

Stress/stram dependencies of the critical current $I_c$ in AgMgNi sheathed multifilamentary Bi(2212) superconducting tapes were evaluated at 77K, 0T. The external reinforcement was accomplished by soldering Ag-Mg tapes to sin91e side or both sides of the sample. With the external reinforcement. the strength of tapes increased but $I_c$, decreased The $I_c$, degradation characteristic according to the external reinforcement was improved markedly in terms of the stress although it appeared less rectal.table on the basis of the strain. Effects of external reinforcement were discussed in a viewpoint of monitoring sensitivity of cracking in superconducting filaments by considering n-value representing the transport behavior of the current. It is closely associated with the location of them relative to the voltage-monitoring region in the tape.

• 한국인터넷방송통신학회논문지
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• 제17권1호
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• pp.213-218
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• 2017

발전소에서 전기를 생산 및 공급하기 위하여 고전압 전력 시스템이 동작하고 있다. 고전압 시스템은 저전압 시스템과 비교하여 구조가 복잡하고, 규모가 크고, 가격이 비쌀 뿐만 아니라. 사고 발생시 저압 시스템을 포함하는 대부분의 설비들에 정전사고가 발생하여 막대한 경제적 손실을 초래한다. 설계부터 시공 및 관리를 더욱 철저히 해야 한다. 설치환경 및 사용 조건 부하량 등에 따라 차이가 있겠지만, 증설과정, 부적절한 설계 등으로 인하여 케이블의 단면적이 부족할 경우가 발생하며, 운전 전류에 의하여 초과된 허용온도는 케이블의 열화 상태를 초래한다. 우리는 케이블의 사고를 체계적으로 감시 및 예방하기 위한 측정 장비를 개발, 한국서부발전 주식회사(Korean Western Power Co. Ltd.)에 설치하여 활선 케이블을 진단하였다. 이 논문에서 우리는 케이블의 부하전류를 측정하고, 측정된 부하전류에 의한 온도 특성을 예측 연구한 결과를 제시한다. 이 온도 값을 해석하여 케이블의 열화에 미치는 영향을 예측할 수 있다.

• 한국전기전자재료학회논문지
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• 제24권6호
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• pp.504-509
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• 2011

The conducting current of non-uniform plasma immersed electrode consists of ion current and secondary electron emission current caused by the impinging ion current. The ion current is determined by the ion dose passing through the sheath in front of electrode and the ion distribution in front of the electrode plays an important role in the secondary electron emission. The investigation of the distributed plasma and secondary electron effect on electrode ion current was carried out as the stainless steel electrode plugged with quartz tube was immersed in the inductively coupled Ar plasma using the antenna powered by 1 kw and the density profile was measured. After that, the negative voltage was applied by 1 kV~6 kV to measure the conduction current for the analysis of ion current.

• 대한관절경학회지
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• 제12권1호
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• pp.69-73
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• 2008

활액막 연골종증은 흔하지 않은 질환으로 견관절에 발생하는 경우는 드물다. 15세 여자 환자가 견관절 통증을 호소하여, 단순 방사선 검사 및 MRI 검사로 활액막 연골종증으로 진단하였고, 병변이 견관절뿐만 아니라 상완 이두건 건초 내로 침범 되었다. 저자들은 견관절 병변은 관절경 시술로, 그리고 상완 이두건 건초 내 병변에 대해서는 소절개를 통한 유리체 제거 및 활액막 전 절제술을 시행하였다. 비록 견관절경 시술이 적은 합병증 및 우수한 수술 시야를 제공하지만, 관절경 시술로는 이두 구내의 활액막과 건초 병변에 대한 완벽한 치료는 매우 어렵다. 이에 저자들은 이두 구까지 침범된 견관절에 발생한 활액막 연골종증의 완벽한 치료를 위해, 관절경적 활액막 전 절제술 및 유리체 제거술과 더불어 상완 이두건 건초의 소절개를 통한 병소의 완전 제거가 필요하여 문헌고찰과 함께 보고하고자 한다.