• 제목/요약/키워드: large-cell

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다층막 구조를 이용한 유기 EL소자의 제작과 특성에 관한 연구 (Preparation and Characteristics of Organic Electroluminescence Devices Using Multilayer structure with Carrier Transport Materials)

  • 이상윤;김태완;최종선;김영관;김정수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.249-252
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    • 1997
  • Electroluminescence(EL) devices based on organic thin layers have attracted lot of interests because of their possible application as large-area display-emitting display. One of the problems of such devices is lifetime of the cell, where the degradation of the cell is partially due to the crystalliyzation of organic layers. In large part, this problem can be solved by using a multilayer device structure prepared by vapor deposition technique. In this study, blue light-emitting multilayer organic electroluminescence devices were fabricated vsing Poly (9-vinylcarbaEole) (PVK) and 2- (4-tert-butylphenyl)-5-(4$^{#}$-bis-phenyl) 1,3,4-oxadiazole (PBO) as hole trasport and electron transport material, respectively, where trim(8-hyd roxyquinolinate) aluminum (Al $q_3$) was used as a luminescenct material. A cell structure of glass sub- strate/indume-tin-oxide(ITO)/PCK/Al $q_3$/PBD/Mg:In was employed. Blue emission peak at 510nm was observed with this cell structure.e.

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경쟁 학습 신경회로망을 이용한 기계-부품군 형성에 관한 연구 (Machine-Part Cell Formation by Competitive Learning Neural Network)

  • 이성도;노상도;이교일
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.432-437
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    • 1997
  • In this paper, Fuzzy ART which is one of the competitive learing neural networks is applied to machine-part cell formation problem. A large matrix and varios types of machine-part incidence matrices, especially including bottle-neck machines, bottle-neck parts, parts shared by several cells, and machines shared by several cells are used to test the performannce of Fuzzy ART neural network as a cell formation algorithm. The result shows Fuzzy ART neral network can be efficiently applied to machine-part cell formation problem which are large, and/or have much imperfection as exceptions, bottle-neck machines, and bottle-neck parts.

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육용계의 피부에 발생한 편평세포암종 (Cutaneous Squamous Cell Carcinoma Occurred in Broiler Chickens)

  • 조경오
    • 한국수의병리학회지
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    • 제5권2호
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    • pp.63-66
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    • 2001
  • Two 53-day-old broiler chickens were condemned due to multiple cutaneous nodular masses at slaughter house. Grossly, variable sized round masses were scattered in the abdomen and pelvis. Some of them were large and fused each other. Center of large fused nodules were ulcerated. Histopathologically, tumor masses consisted of multiple cords or masses of epidermal cells. Some of \ulcornerem contained central conoentric lamella of keratin (cancer pearl). From these results, these cases were diagnosed as cutaneous squamous cell carcinoma. This is the first report of cutaneous squamous cell carcinoma occurred in broiler chickens in Korea.

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과립세포종양의 압착도말 세포학적 소견 -1예 보고- (Imprint Cytology of Granular Cell Tumor -A Case Report-)

  • 성우정;최준혁
    • 대한세포병리학회지
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    • 제18권2호
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    • pp.170-174
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    • 2007
  • Granular cell tumor is a rare tumor of the soft tissue and this is characterized by proliferation of large cells with granular appearing eosinophilic cytoplasm. We report the imprint cytologic features of a case of granular cell tumor in the left calf of a 52-year-old woman. Microscopic examination showed moderate cellularity. The tumor cells were arranged both as single cells and in clusters. The cells were large polygonal-shaped and they had small round nuclei with finely granular chromatin and occasionally conspicuous nucleoli. The cytoplasm was abundant eosinophilic and granular. Naked nuclei and spindle-shaped tumor cells were occasionally noted. No mitosis and necrosis were present. The background showed cytoplasmic granular materials. The tumor cells showed positivity for S-100 protein. Ultrastructurally, abundant lysosomes were present in the cytoplasm of the tumor cells.

직접 메탄올 연료전지용 대면적 막-전극 접합체 공기극의 위치별 열화 현상 (Position-Dependent Cathode Degradation of Large Scale Membrane Electrode Assembly for Direct Methanol Fuel Cell)

  • 김수길;이은숙;김이영;김장미;조한익;하흥용
    • 전기화학회지
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    • 제12권2호
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    • pp.148-154
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    • 2009
  • 대면적 ($150cm^2$) 막전극 접합체(MEA)를 사용하는 직접메탄올연료전지(DMFC)의 내구성과 관련하여, 장시간 운전에 따른 공기극의 열화 현상을 공기극면의 위치별로 고찰하였다. 500시간 동안 정전류 조건으로 운전한 대면적 MEA를 공기극 입구, 중간, 출구의 세 부분으로 분할 하여 각각의 MEA에 대한 성능을 관찰한 결과, 대면적 MEA 운전시 홍수 (flooding) 현상이 심했던 공기극 출구 쪽 MEA의 성능 저하가 두드러졌다. 이는 홍수 현상에 의한 촉매의 열화 및 GDL의 박리에 의한 것으로 판단된다. 이 중 특히 촉매의 열화 현상과 관련하여, 출구 방향으로 갈수록 촉매의 전기화학적 활성 면적의 감소가 관찰되나 이는 촉매 입자의 뭉침 (agglomeration) 현상에 의한 것이라기 보다는 촉매 입자의 용해 (dissolution)와 이동 (migration)으로 인한 촉매의 유실 때문인 것으로 판단된다. 전체적인 성능 감소 및 촉매의 열화 정도는 공기극의 홍수와 직접적인 비례관계가 있으며, 이를 해소하기 위한 물관리 기법 및 분리판 디자인의 개선이 요구된다.

Microstructural Characteristics of the Ordered and Disordered Leaves in Citrus junos Sieb.

  • Park, Min-Hee;Boo, Hee-Ock;Kim, Hong-Sub;Lee, Sook-Young
    • Plant Resources
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    • 제3권3호
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    • pp.163-172
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    • 2000
  • We compared microstructural features of the ordered cell and disordered leaves in Citrus junos Sieb. by electron microscopy. In the cell of the ordered leaves, many chloroplasts and large vacuoles were particularly observed. Also a lot of vessel, companion cell and big nucleus were presented in vascular bundle regions. The mitochondria and the other organelles were interspersed among the chloroplasts in a thin, peripheral layer of cytoplasm. The chloroplast possessed typical grana and intergranal lamellae, numerous starch grains and a few small osmophilic globules. Besides, microbodies were closely associated with the mitochondria and the chloroplast. The process of the formation of the secondary cell wall from primary cell wall was observed the vessel elements, the tonoplast wall and the secondary cell wall. It was observed that the oil sac with the unique perfume distributed the adjacent cell wall. In the cell of disordered leaves, the all of the organelles were thrust toward the cell wall due to the fusion of vacuoles in the cells. It was observed that a lot of the very small particles spreaded in the cytoplasm. The loss of unique perfume of the leaves was resulted in the destruction of the oil sac. Also, there was not observed grana, lamellae, starch and osmophillic globules in the chloroplast. The small distributed organelles was not observed but the elongation of the cell wall was proceed no longer. Therefore, the plasma membrane diverged from the cell wall. All of organelles in the cell had poor function and deformation. A massive vacuole was fulfilled in single cell and the vacuole contains a lot of large and small particles. The organelles were presented on the side of the cell wall according to the enlargement of vacuole and they were observed to be breakdown.

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절피원심법으로 대규모 채취한 누에체액의 곤충세포 증식효과 (Effect of Silkworm Hemolymph Collected Large-scale Bleeding Method in Insect Cell Culture)

  • 최지영;김종길;최영철;김삼은;한명세
    • 한국잠사곤충학회지
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    • 제49권1호
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    • pp.28-32
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    • 2007
  • 누에체액이 동물세포 배양의 필수첨가물인 FBS를 대체할 수 있는 세포증식 효과가 있는 것으로 확인되었으나, 누에의 배발에 상처를 내어 채혈하는 방법으로는 대량 채취가 어렵다. 본 연구에서는 이러한 문제점을 해결코자 대량의 체액을 한꺼번에 얻을 수 있는 대규모 채혈법을 검토하게 되었다. 1. 누에 머리부분과 꼬리부분(배발 포함)에 상처를 낸 후 원심하여 체액을 채취하는 방법(절피원심법)이 기존의 소규모 채취한 체액과 유사한 세포증식 촉진효과를 보였다. 2. 절피원심한 체액의 원심속도에 따른 세포증식 촉진 효과는 500rpm과 1000rpm에서 양호한 값을 보였다. 3. 원심속도를 500rpm으로 고정한 경우 원심시간을 5분에서 30분까지 달리하여도 세포증식 효과는 유사하였고, 체액 회수율은 원심시간이 길어질수록 증가하였으나 일정시간 이상부터는 증가하지 않았다. 4. 절피원심법으로 대규모 채취한 체액의 액상회수율은 누에(백옥잠)생체중의 19.5%이었고, 분말회수율은 1.4% 이었으며, 분말체액에서도 세포증식 촉진 효과가 인정되었다.

Process Development of therapeutic antibody (ISU301) using disposable bioreactor

  • Park, Heung-Rok
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVI)
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    • pp.39-39
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    • 2005
  • Large scale mammalian cell culture has become, over the past two decades, the preferred method to produce therapeutic monoclonal antibodies. In this presentation, I will introduce disposable bioreactor system and analyze key factors and points for consideration during mammalian cell culture process development. Example will be provided highlighting the selection of master cell, culture media and environmental factors based on productivity and product quality.

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Collison Tumor of Adenocarcinoma and Diffuse Large B-Cell Lymphoma in the Rectum: a Case Report and Literature Review

  • Kim, See Hyung
    • Investigative Magnetic Resonance Imaging
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    • 제23권4호
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    • pp.374-380
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    • 2019
  • Collision tumor is a synchronous neoplasm wherein two histologically distinct tumors co-exist within the same anastomosis site. Collision tumor can occur in any organ, but the incidence is markedly rare. Additionally, preoperative diagnosis can be challenging to the radiologist. Herein, we report an age 60 male with collision tumor of rectal adenocarcinoma and diffuse large B-cell lymphoma, presented as a semi-annular wall thickening and bulky exophytic mass on MR imaging.