• 제목/요약/키워드: internal migration

검색결과 191건 처리시간 0.034초

PCB 절연체에서 전하 형성과 수분 흡수 (Water Absorption and Charge Formation in PCB)

  • 이정수;황종선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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    • pp.233-234
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    • 2008
  • We observed internal space charge behavior for two types of epoxy composites under dc electric fields to investigate the influence of water at high temperature. In the case of glass/epoxy specimen, homocharge is observed at water-treated specimen, and spatial oscillations become clearer in the water-treated specimens. Electric field in the vicinity of the electrodes shows the injection of homocharge. In aramid/epoxy specimens, heterocharge is observed at water-treated specimens, i.e. negative charge accumulates near the anode, while positive charge accumulates near the cathode. Electric field is enhanced just before each electrode. In order to further examine the mechanism of space charge formation, we have developed a new system that allows in situ space charge observation during ion migration tests at high temperature and high humidity. Using this in situ system.

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PCB 절연체에서 전하 형성과 수분 흡수의 영향 (Influence of Water Absorption and Charge Formation in PCB)

  • 구정현;최용성;이경섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.2307-2308
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    • 2008
  • We observed internal space charge behavior for two types of epoxy composites under dc electric fields to investigate the influence of water at high temperature. In the case of glass/epoxy specimen, homocharge is observed at water-treated specimen, and spatial oscillations become clearer in the water-treated specimens. Electric field in the vicinity of the electrodes shows the injection of homocharge. In aramid/epoxy specimens, heterocharge is observed at water-treated specimens, i.e. negative charge accumulates near the anode, while positive charge accumulates near the cathode. Electric field is enhanced just before each electrode. In order to further examine the mechanism of space charge formation, we have developed a new system that allows in situ space charge observation during ion migration tests at high temperature and high humidity. Using this in situ system.

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동위원소 주사로 확인된 복수의 이동에 의한 수흉 (Scintigraphic Demonstration of Trans-Diaphragmatic Migration of Ascites)

  • 서흥석;강종명;조석신
    • 대한핵의학회지
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    • 제21권1호
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    • pp.79-82
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    • 1987
  • 염증성 복부질환에서 늑막침윤이 일어나는 기전에 대하여는 잘 알려져 있으나, 비염증성 복수의 늑막강내로의 이동에 관여하는 기전에 대하여는 여러가지 가설이 제시되어 있다. 저자들은 만성 신부전증 환자에서 Tenckhoff 카테타의 복강내 이식후 발생한 우측 수흉이 투석액의 이동에 의한 것임을 동위원소주사법을 통하여 확인하였는 바, 이에 관여하는 기전에 대한 문헌고찰과 함께 보고하는 바이다.

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누두흉의 외과적 치료 -Metal bar를 이용한 수술치험 7예- (Operative treatment of pectus excavatum -7 cases used retrosternal metal bar-)

  • 이정철
    • Journal of Chest Surgery
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    • 제19권3호
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    • pp.391-398
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    • 1986
  • From Jan. 1983 to Dec. 1985, seven cases of pectus excavatum, six were male and one female, were underwent an operation at the Department of Thoracic and Cardiovascular Surgery, Kyungpook National University Hospital. The ages of patients ranged from 6 to 27 years. They all had symptoms of feeling inferiority about chest deformity. The concavity on the funnel chest varied in its extent, and the severity, which was measured by water volume filled into it, varied from 59.5cc/m2 to 129.9cc/m2. All but one patients were approached through a bilateral transverse submammary incision and one approached through a vertical midline incision. Successful surgical correction required resection of all deformed costal cartilages with transverse anterior osteotomy and internal fixation using retrosternal metal bar. No serious complication have followed the use of this technique, but minor complications such as serous accumulation, pneumothorax and strut migration have been experienced. All patients were satisfactory about the surgical results.

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화학증폭형 감광제의 노광후 지연 효과에 대한 모델링 및 시뮬레이션 (Post Exposure Delay Effect Modeling and Simulation in Chemically Amplified Resists)

  • 김상곤;손동수;박흥진;손영수;오혜근
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.78-79
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    • 2001
  • 노광 후 지연(Post Exposure Delay: PED) 효과는 그림 1과 같이 노광 후 지연 시간에 따른 감광제의 Profile에 thinning, T-top, foot, undercut 를 보여주는 현상으로 화학 증폭형 감광제(Chemically Amplified Resist, CAR) 개발에 있어 PED의 안정성은 중요한 요소이다(1). 따라서 노광후 지연 효과에 대한 모델링은 연구와 개발을 위한 시뮬레이션 tool에 있어 매우 의미 있는 일이다. T-top 이나 undercut 를 형성하는 Surface inhibition layer(SIL) 은 노광 후 지연시 발생되는 environmental base contamination, acid evaporation 이 주요 원인이며 다른 원인으로는 감광제 속에서 acid migration, spin coating 동안에 photoacid generator (PAG)의 고갈, internal basic impurities 이며 그 외에 nonbsic atmospheric contamination, high power laser source의 영향 등이 있다. (중략)

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Small GTPases and formins in mammalian oocyte maturation: cytoskeletal organizers

  • Kwon, So-Jung;Lim, Hyun-Jung J.
    • Clinical and Experimental Reproductive Medicine
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    • 제38권1호
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    • pp.1-5
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    • 2011
  • The maturation process of mammalian oocytes accompanies an extensive rearrangement of the cytoskeleton and associated proteins. As this process requires a delicate interplay between the cytoskeleton and its regulators, it is often targeted by various external and internal adversaries that affect the congression and/or segregation of chromosomes. Asymmetric cell division in oocytes also requires specific regulators of the cytoskeleton, including formin-2 and small GTPases. Recent literature providing clues regarding how actin filaments and microtubules interact during spindle migration in mouse oocytes are highlighted in this review.

전분 분무기술을 통한 다층지의 물성개선 (Improvement of Multiply Board Properties with Starch Spraying)

  • 이학래;류정용
    • 펄프종이기술
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    • 제39권3호
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    • pp.12-23
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    • 2007
  • Frequently spraying of natural starch slurry onto the formed wet web has been adopted to improve properties of paperboards. This conventional starch spraying technique, however, becomes less effective in strength improvement. In this study the effects of various factors including wet web dryness, quantity of starch slurry sprayed, and drying temperature on paperboard properties were investigated. Migration of starch granules into the webs appeared to cause a reduction in plybond strength when the web dryness was lower than this level. Wet webs should contain enough water to swell the starch granules, and at the same time they should be heated to a temperature high enough for complete cooking of the sprayed starches to occur. This suggested that preheating of the wet web can be employed to improve the plybond strength.

자궁경부봉축술 후 발생한 방광석 및 방광질루 1 예 (A Case of Bladder Stone and Vesicovaginal Fistula after McDonald Operation)

  • 윤창준;문기학;정희창
    • Journal of Yeungnam Medical Science
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    • 제23권1호
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    • pp.108-112
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    • 2006
  • The frequency of a bladder foreign body in the female is lower than in the male, and bladder stones attached to foreign bodies such as non-absorbable suture material are not common. Moreover, vesicovaginal fistulas due to migration or puncture of suture materials into the bladder are rare. In this report, we present a case of bladder stone and vesicovaginal fistula formation in a 29-year-old female patient who had been treated with the McDonald operation for an incompetent internal os of the cervix (IIOC) during pregnancy. The patient was successfully treated by cystoscopic removal of the bladder stone with suture material and conservative treatment for the vesicovaginal fistula.

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Mechanical Property and Problems of the Self-expandable Metal Stent in Pancreaticobiliary Cancer

  • Thanawat Luangsukrerk
    • Journal of Digestive Cancer Research
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    • 제10권2호
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    • pp.92-98
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    • 2022
  • Self-expandable metal stent (SEMS) is effective for biliary drainage, especially in pancreaticobiliary cancer. The mechanical properties, material, and design of SEMS are important in preventing recurrent biliary obstruction and complication. Radial and chronic expansion forces play roles in preventing stent migration and collapse. Complications, such as stent impaction, cholecystitis, and pancreatitis, were related to the axial force. The nickel-titanium alloy shows more flexibility, conformability, and optimal axial force compared to previously used stainless steel. Additionally, the stent structure affected the mechanical properties of SEMS. Therefore, understanding the mechanical properties, material, and design of SEMS will provide the best outcome for biliary drainage, as well as better SEMS development.

길경 수용액 추출물에 의한 인체 폐암세포의 성장억제 기전 연구 (Cell Cycle Arrest of Human Lung Carcinoma A549 Cells by an Aqueous Extract from the Roots of Platycodon grandiflorum)

  • 강락원;이재원;감철우;최병태;최영현;박동일
    • 동의생리병리학회지
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    • 제17권1호
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    • pp.183-189
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    • 2003
  • Platycodi Radix, the root of Platycodon grandiflorum, commonly known as Doraji, is used as a traditional oriental medicine. Extracts from the roots of P. grandiflorum have been reported to have wide ranging health benefits. We investigated the effects of an aqueous extract from the roots of P. grandiflorum (AEPG) on the cell proliferation of human lung carcinoma A549 cells in order to understand its anti-proliferative mechanism. AEPG treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. This anti-proliferative effect of A549 cells by AEPG treatment was associated with morphological changes such as membrane shrinking, cell rounding up and inhibition of cell migration. DNA flow cytometric histograms showed that populations of both Sand G2/M phase of the cell cycle were increased by AEPG treatment in a concentration-dependent manner. AEPG treatment induced a marked accumulation of tumor suppressor p53 and a concomitant induction of cyclin-dependent kinase (Cdk) inhibitor p21 and p27. In addition, SSS treatment resulted in down-regulation of Cdk2 and Cdk4 expression. The present results indicated that AEPG-induced inhibition of lung cancer cell proliferation is associated with the blockage of S to G2/M phase progression the induction of apoptosis. Taken together, these findings suggest that P. grandiflorum has strong potential for development as an agent for prevention against human lung cancer.