• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권6호
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• pp.267-272
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• 2002

This Paper deals with the short circuit tests of the three-Phase DC reactor type fault current limiter (FCL) in changing of turns ratio of transformers. The experiment of this paper is a preliminary step to develop the FCL's faculties for an application to high voltage transmission line. So, superconducting coil was made of Nb-Ti, low temperature superconductor, and the ratings of the power system of experimental circuit are 400V/7A class. A three-phase DC reactor type FCL consists of three transformers, six diodes, one superconducting coil and one cryostat. The important point of experimental analysis is transient period, the operating lagging time of circuit breaker. As the results of the experiment, the values are referred to the limitation rate about 77% and 90% when the turns ratio of transformer was 1:1 and 2:1 respectively.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.811-813
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• 2009

Purpose: Congenital cleft earlobe is relatively rare malformation and defective type congenital cleft earlobes are reconstructed with mainly local flap methods rather than primary closure or z - plasty. Various methods are introduced but many of these remain visible scars or require complex operative techniques. We designed a new and simple method of reconstruction for defective type cleft earlobe. Methods: On the posterior surface of the auricle and mastoid area, S - shaped line was drawn continuously. One arc is for turnover hinge flap to make the anterolateral surface of the earlobe, and the other is for transposition flap to reconstruct the posterolateral surface. The donor site of the transposition flap was closed primarily. Results: Four patients were operated by S - shaped flap design method. They were all female and two were right side and others were left. We obtained aesthetically satisfactory postoperative results with inconspicuous scars at the posterior side of the auricle. In one case, minor revision was performed because of insufficient blood supply of the hinge flap. Conclusion: We can reconstruct defective type cleft earlobe with new, simple S - shaped design for hinge flap and transposition flap.

• 감성과학
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• 제12권2호
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• pp.193-204
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• 2009

최근 마케팅 분야에서 기업 이미지디자인의 중요성이 부각되고 있다. 그런데 기업의 이미지를 대표하는 마크 중 로고타입은 심볼마크와 로고마크에 비해 상대적으로 소홀히 다루어져 왔다. 로고타입은 심볼마크와 함께 기업의 개성과 특성을 함축적으로 나타내는 것이어야 하고, 이를 위해서는 형태에 의한 이미지 표현이 중요시되며, 따라서 시각디자인의 조형적인 측면이 중요하게 고찰되어야 한다. 그런데 로고타입과 로고마크에 관한 조형적 측면에서의 연구, 특히 글꼴의 형태와 이에 대한 소비자의 반응에 관한 연구가 부족한 실정이다. 이에 본 연구에서는 소비자들이 선호하는 한글 로고타입의 시각적인 형태와, 기업에 따라 선호되는 로고타입의 형태에 관해 살펴보았다. 연구 결과 기업의 업종에 따라 선호되는 로고타입의 형태요소에 차이가 있었는데, 건설회사 로고타입에서는 돋음체 계열의 몸통에 줄기 굵음, 돌기 없음, 사선형 맺음, 직선곡선형 맺음이 선호되고, 은행의 로고타입에서는 돋음체 계열의 몸통에 돌기 없음, 사선형 맺음, 한쪽곡선형 돌기, 줄기는 중간이 선호되며, 연구소의 로고타입에서는 돋음체 계열의 몸통에 사선형 맺음, 줄기 굵음, 직선형 돌기가 선호되는 것으로 나타났다. 건설회사, 은행, 연구소의 로고타입 형태에 공통적으로 적용해야 할 요소는 사선형 맺음으로 나타났고, 곡선형 맺음과 줄기 얇음은 피해야 될 것으로 나타났다. 반면 돌기, 맺음, 굴림은 기업의 업종에 따라 다르게 적용해야 하는 것으로 나타났다.

• 대한약리학회지
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• 제29권1호
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• pp.139-148
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• 1993

SCC 12와 SCC 13 세포주는 피부의 상피암 조직에서 유래되었다. 본 연구에서는, 세포배양으로 in vivo 피부의 거의 모든 특징들을 재현할 수 있는 raft 배양법을 이용하여, 두 종류의 상피 암세포주의 진피 침투성 정도를 비교해 보았다. SCC 12 세포주의 raft 배양에서는, collagen matrix로 침투하는 많은 세포군들이 관찰되었고, 또한 기저세포와 유사한 세포들이 분화층 중간에 관찰되었다. 그러나 SCC 13 세포주의 raft 배양에서는 침투성 세포들이 전혀 관찰되지 않았다. 어떤 인자가 SCC 12 세포주의 침투성에 관여하였는지를 조사하기 위하여, 세포이동 또는 matrix 파괴에 관여하는 각종 단백질 즉, type 1 collagenase, Fn, Fn 수용체와 EGF 수용체 등의 기본 생합성속도를 침투성과 비침투성 세포주에서 측정하였다. 그 중 type 1 collagenase의 생합성만이 침투성 세포주에서 현저히 높게 나타났다. 침투성 SCC 12 세포주에서 관찰된 높은 type 1 collagenase 생합성과 이들 세포주의 침투성과의 연관관계 및 그 기작을 조사하기 위하여 두 세포주에서 TGF alpha에 대한 반응의 차이를 조사하였다. 비침투성 세포주에서는, TGF alpha에 의해 type 1 collagenase의 생합성이 처음 12시간 동안에 현저한 증가를 보였으나 24시간부터 그 유도가 down-regulation되는 현상을 보였다. 그러나 침투성 세포는 TGF alpha에 의해 계속적인 type 1 collagenase의 유도를 보였다. 이에 저자들은 EGF 수용체의 down-regulation으로 인해 type 1 collagenase의 down-regulation이 유도되고, 이와 같은 regulation의 결함으로 인해 SCC 12 세포주가 collagen matrix로 침투하는 현상을 나타낼 것으로 제시하였다.

• Industrial Engineering and Management Systems
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• 제3권1호
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• pp.52-58
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• 2004

This report examines the issue of designing an efficient production system by increasing several types of flexibility. Increasing manufacturing flexibility is a key strategy for efficiently improving market responsiveness in the face of uncertain market demand for final products. The manufacturing system comprises multiple plants, of which individual plants have multiple manufacturing lines that are designed to produce limited types of products in accordance with their size and materials. Imbalance in the workload occurs among plants as well as among manufacturing lines because of fluctuations in market demand for final products. Thereby, idleness of some manufacturing lines and longer lead times in some manufacturing lines occur as a result of the high workload. We clarify how these types of flexibility affect manufacturing performance by improving only one type of flexibility or by improving multiple types of flexibility simultaneously. The average lead time and the imbalance in workload are adopted as measures of manufacturing performance. Three types of manufacturing flexibility are interrelated: machine flexibility, routing flexibility, and process flexibility. Machine flexibility refers to the various types of operations that a machine can perform without requiring the prohibitive effort of switching from one order to another. Routing flexibility is the capability of processing a given set of part types using more than one line (alternative line) in the plant. Process flexibility results from being able to build different types of final products at the same plant.

• 한국어류학회지
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• 제24권4호
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• pp.247-252
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• 2012

한국산 송사리속 2종에 대한 섭이기관의 구조적 차이를 알아보기 위하여 악골 및 이빨 구조를 조사하였다. 악골에서 송사리 Oryzias latipes는 전상악골 중앙부의 등 쪽 가장자리에 움푹 들어가는 홈이 존재하였으나 대륙송사리 O. sinensis는 일직선이었다. 후반부의 위치에서 송사리는 중앙부와 일직선상에 존재하였으나 대륙송사리는 배 쪽에 존재하였다. 또한 송사리는 하악골의 구상돌기 아래로 이어지는 치골 뒷가장자리에 움푹 들어가는 홈이 존재한 반면에 대륙 송사리에서는 뒷가장자리가 일직선 모양을 하였다. 송사리는 성적이형으로서 수컷에서만 나타나는 큰 이빨이 하악골의 측면 방향으로 발달하였고, 대륙송사리는 등 쪽 방향으로 발달하였다. 한편 송사리의 이빨형태는 원뿔모양과 화살촉모양 2 types이 나타난 반면에 대륙송사리에서는 원뿔 모양 1 type만 나타나는 특징을 보였다. 이상과 같이 한국에 분포하는 2종의 송사리는 섭이기관에서 뚜렷한 종간의 특징을 잘 보여 주었다.

• Plant Biotechnology Reports
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• 제3권4호
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• pp.277-283
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• 2009

One of the limitations to conducting maize Agrobacterium-mediated transformation using explants of immature zygotic embryos routinely is the availability of the explants. To produce immature embryos routinely and continuously requires a well-equipped greenhouse and laborious artificial pollination. To overcome this limitation, an Agrobacterium-mediated transformation system using explants of type II embryogenic calli was developed. Once the type II embryogenic calli are produced, they can be subcultured and/or proliferated conveniently. The objectives of this study were to demonstrate a stable Agrobacterium-mediated transformation of maize using explants of type II embryonic calli and to evaluate the efficiency of the protocol in order to develop herbicide-resistant maize. The type II embryogenic calli were inoculated with Agrobacterium tumefaciens strain C58C1 carrying binary vector pTF102, and then were subsequently cultured on the following media: co-cultivation medium for 1 day, delay medium for 7 days, selection medium for $4{\times}14$ days, regeneration medium, and finally on germination medium. The T-DNA of the vector carried two cassettes (Ubi promoter-EPSPs ORF-nos and 35S promoter-bar ORF-nos). The EPSPs conferred resistance to glyphosate and bar conferred resistance to phosphinothricin. The confirmation of stable transformation and the efficiency of transformation was based on the resistance to phosphinothricin indicated by the growth of putative transgenic calli on selection medium amended with $4mg\;1^{-1}$ phosphinothricin, northern blot analysis of bar gene, and leaf painting assay for detection of bar gene-based herbicide resistance. Northern blot analysis and leaf painting assay confirmed the expression of bar transgenes in the $R_1$ generation. The average transformation efficiency was 0.60%. Based on northern blot analysis and leaf painting assay, line 31 was selected as an elite line of maize resistant to herbicide.

• Transactions on Electrical and Electronic Materials
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• 제18권4호
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• pp.207-210
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• 2017

The suspension arrangement of insulators provides flexibility and assists in power transmission in transmission lines. The performance of the insulator string is strongly influenced by the environmental conditions to which it is exposed, its shape and the inherent material properties of suspension-type insulators. The suspension-type insulators are mostly made from glass, porcelain and ceramic material due to their high resistivity. Irregularity in charge distribution throughout the porcelain insulator may lead to accelerated aging and electrical breakdown. A very high and steep lightning impulse voltage may also cause breakdown of suspension-type insulators. We investigated various material characteristics such as alumina addition, surface morphology, x-ray diffraction pattern and relative density of suspension porcelain insulators manufactured in 1989 (36,000 lbs.), 1995 (36,000 lbs.) and 2001 (36,000 lbs.) by the KRI Company for use in 154 kV high power transmission lines. We compared the material characteristics of these porcelain insulators with that of the top-of-the-line porcelain insulators (36,000 lbs.) manufactured by the NGK Company in 2000. These suspension-type porcelain insulators were exposed to arc and flashover tests to examine their electrical and mechanical strength. It was noted that alumina addition (17 wt.%) for K-2001 was one of the major contributors to the enhancement of the performance of the porcelain insulators and to their ability to withstand very high current generation during the arc test. The porcelain insulators manufactured during 2001 also showed the highest relative density of 95.8% as compared to the other insulators manufactured in 1989 and 1995 respectively 94.2% and 91.5%. We also discuss reports of various failure modes of suspension-type porcelain insulators.

• 한국잡초학회지
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• 제30권4호
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• pp.380-389
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• 2010

본 연구는 유전자총기법에 의해 생산된 형질전환 고구마를 사용하여 glufosinate-ammonium에 대한 저항성 유무를 빠르고, 경제적이며, 신뢰할 수 있는 간이분석법을 찾고자 수행되었다. 저항성 진단법은 whole-plant 진단법, one leaf 진단법 및 leaf disk 진단법을 사용하였고, 이들 진단법에 의해 glufosinateammonium을 처리하고 잎의 피해율과 암모늄 축적량을 조사하였다. Leaf disk 진단법에서 glufosinateammonium 처리 후 형질전환 라인 7171의 잎에 대한 약해는 wild type에 비해 1.9배 낮았다. One leaf 진단법과 whole plant 진단법의 경우 glufosinateammonium 처리 후 7171의 잎에 대한 약해는 wild type에 비해 각각 59배와 92배 적었다. Leaf disk, one leaf와 whole plant 진단법에서 0.5-5mM glufosinateammonium 처리 후 암모늄 축적은 wild type이 7171에 비해 각각 2-20, 4-43 및 6-115배 더 많이 축적되었다. 이들 3가지 방법 모두 형질전환 고구마에 대한 glufosinate-ammonium 저항성 유무를 판단하는데 가능한 방법이나 one leaf 진단법이 가장 간편하면서 빠른 진단방법이었다. 그러나 이 방법은 엽령별 내성차이가 존재할 수 있어 고구마 엽이 10개 전개되었을 때 1, 3, 5, 7, 9엽을 각각 채취하여 3mM glufosinateammonium을 처리시 잎의 피해율과 암모늄 축적을 엽령별로 조사한 결과 유의적인 차이를 보이지 않았다. 따라서 분석에 소요되는 기간, 시료량, 정확성 등을 고려할 때 형질전환 고구마의 저항성을 판별하는데 one leaf 진단법이 가장 적합한 것으로 판명 되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.35-38
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• 2002

In this paper, the characteristics of channel hot electron (CHE) injection for the write operation in a NOR-type SONOS flash memory with common source line were investigated. The thicknesses of he tunnel oxide, the memory nitride， and the blocking oxide layers for the gate insulator of the fabricated SONOS devices were $34{\AA}$, $73{\AA}$, and $34{\AA}$, respectively. The SONOS devices compared to floating gate devices have many advantages, which are a simpler cell structure, compatibility with conventional logic CMOS process and a superior scalability. For these reasons, the introduction of SONOS device has stimulated. In the conventional SONOS devices, Modified Folwer-Nordheim (MFN) tunneling and CHE injection for writing require high voltages, which are typically in the range of 9 V to 15 V. However CHE injection in our devices was achieved with the single power supply of 5 V. To demonstrate CHE injection, substrate current (Isub) and one-shot programming curve were investigated. The memory window of about 3.2 V and the write speed of $100{\mu}s$ were obtained. Also, the disturbance and drain turn-on leakage during CHE injection were not affected in the SONOS array. These results show that CHE injection can be achieved with a low voltage and single power supply, and applied for the high speed program of the SONOS memory devices.