• 제목/요약/키워드: Disappearance

검색결과 855건 처리시간 0.023초

Three phase flow simulations using the fractional flow based approach with general initial and boundary conditions

  • Suk, Heejun
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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    • pp.88-91
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    • 2004
  • The multiphase flow simulator, MPS, is developed based on the fractional flow approach considering tile fully three phase flow with general initial and boundary condition. Most existing fractional flow-based models are limited to two-phase flow and specific boundary conditions. Although there appears a number of three-phase flow models, they were mostly developed using pressure based approaches. As a result, these models require cumbersome variable-switch techniques to deal with phase appearance and disappearance. The use of fractional flow based approach in MPS makes it unnecessary to use variable-switch to handle the change of phase configurations. Also most existing fractional flow based models consider only specific boundary conditions. However, the present model considers general boundary conditions of most possible and plausible cases which consists of ten cases.

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Cytological Modification of Sorghum Leaf Tissues Showing the Early Acute Response to Maize Dwrf Mosaic Virus

  • Choi, Chang-Won
    • Journal of Plant Biology
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    • 제39권3호
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    • pp.215-221
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    • 1996
  • Sorghum leaf tissues showing the early acute response of systemic infection with maize dwarf mosaic virus (MDMV) strain A, contained unusual virus-induced cytological modifications including cell wall thickenings and protrusions, intercellular vesicles termed as "paramural bodies", modified plasmodesmata, abnormal plastids, and cylindrical inclusion bodies. Abnormal cell wall, some of which associated with paramural bodies, was frequently contained modified plasmodesmata. Various abnormal plastids were located within infected cells of leaf tissues showing the early acute response. The most important changes in chloroplast seen in the tissues are the presence of small vesicles, deformation of membranes, reduction in granal stack height, disappearance of osmiophilic globules and degeneration of stuctures. The cytological modification was not occurred in nucleus but a group of degenerated mitochondria with abnormal membranes attached to cylindrical inclusion bodies were observed. It was hard more or less to prove the relationship clearly between virus and cellular organelles in virus replication.plication.

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아크릴 중합체 및 아크릴-이타코닉산 공중합체/ 디메틸술폭시드 용액의 유변학적 특성의 시간의존성 (Time Dependence of the Rheological Properties of the Solutions of Polyacrylontrile and Acrylonitrile-Itaconic Acid Copolymer in Dimethyl sulfoxide)

  • 이남순
    • 한국염색가공학회지
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    • 제13권6호
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    • pp.435-440
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    • 2001
  • This study investigates the rheological properties of in-situ polymerized solutions of polyacrylonitrile(PAN) and acrylonitrile(AN) -itaconic acid(IA) in dimethyl sulfoxide(DMSO) in terms of temperature, concentration, and time. The complex viscosity and storage modulus of the solutions were generally increased with elapsing time, which is ascribable to the three-dimensional pseudostructures formed by strong inter- or Intra-molecular attractions through Polar -CN and -COOH groups. The three-dimensional pseudonetworks would lead to relation of the acrylic solutions in long term. This was more noticeable at higher temperature within the temperature range examined. In the case of 20% solutions one can not observe lower Newtonian flow region in the viscosity curve. Disappearance of lower Newtonian flow region is indicative of heterogeneity of the solution system. Casson Plot of the viscosity data revealed that 20% solutions of PAN and AN-IA copolymer in DMSO clearly demonstrated positive yield stress, ascertaining formation of pseudostructures in the solution systems.

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아크릴 중합체 및 아크릴-이타코닉산 공중합체/디메틸술폭시드 용액의 유변학적 특성의 시간의존성 (Time Dependence of the Rheological Properties of the Solutions of Polyacrylontrile and Acrylonitrile-Itaconic Acid Copolymer in Dimethyl sulfoxide)

  • 이남순
    • 한국염색가공학회지
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    • 제13권6호
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    • pp.77-77
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    • 2001
  • This study investigates the rheological properties of in-situ polymerized solutions of polyacrylonitrile(PAN) and acrylonitrile(AN)-itaconic acid(IA) in dimethyl sulfoxide(DMSO) in terms of temperature, concentration, and time. The complex viscosity and storage modulus of the solutions were generally increased with elapsing time, which is ascribable to the three-dimensional pseudostructures formed by strong inter- or intra-molecular attractions through Polar -CN and -COOH groups. The three-dimensional pseudonetworks would lead to gelation of the acrylic solutions in long term. This was more noticeable at higher temperature within the temperature range examined. In the case of 20% solutions one can not observe lower Newtonian flow region in the viscosity curve. Disappearance of lower Newtonian flow region is indicative of heterogeneity of the solution system. Casson Plot of the viscosity data revealed that 20% solutions of PAN and AN-IA copolymer in DMSO clearly demonstrated positive yield stress, ascertaining formation of pseudostructures in the solution systems.

동맥관개존증, 심실중격결손 및 폐동맥이 동반된 폐동맥 폐쇄증: 1예보고 (A Case Report of Pulmonary Atresia with Pulmonary Artery, PDA and Ventricular Septal Defect)

  • 윤양구;홍승록
    • Journal of Chest Surgery
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    • 제24권2호
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    • pp.212-216
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    • 1991
  • A surgical correction was successfully performed in a adult female who had pulmonary atresia with almost non-confluent pulmonary artery, PDA and ventricular septal defect. Initially as a first stage of corrective surgery isolation of patent ductus arteriosus, ligation of aortopulmonary collaterals and identification of the pathologic anatomy of left pulmonary artery through left posterolateral approach were performed. At the second stage, a week after the initial operation, total correction was done making both pulmonary arteries confluent with albumin coated woven-dacron graft, external valved conduit and closure of large VSD of subarterial and perimembranous type. The PDA was ligated with previously encircled heavy stitch soon after partial bypass was started. Although massive bleeding from anastomotic site of dilated left pulmonary artery to the graft occurred preoperatively, postoperative functional improvement was excellent in terms of disappearance of cyanosis and normal exercise tolerance.

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Annexin I의 구조와 결합에 관한 분광학적 연구

  • 이봉진;방근수;이연희;이태우;나도선
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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    • pp.263-263
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    • 1994
  • Annexin I is a member of the in family of calcium dependent phospholipid banding proteins and is an in vitro phospholipase $A_2$ (PLA$_2$) inhibitor. The mechanism of PLA$_2$ inhibition by annexin I is still ambiguous. The structure of annexin I was studied at the atomic level by using nuclear magnetic resonance (NMR), circular dichrotsm (CD) and fluorescence spectroscopy. Recombinant human annexin I and N-terminally truncated annexin I (1-31 deleted: d-annexin I) were purified and their NMR spectra were compared. The NMR spectra of the two were similar. When $Ca^{2+}$ ion added to annexin I ad d-annexin I, peak broadening occurred, but no significant spectroscopic change was observed. When porcine pancreatic PLA$_2$ was added to deuterium labeled annexin I, an interaction of annexin I with PLA$_2$ was observed as indicated by the disappearance and shift of several peaks in the NMR spectrum. This result supports a protein-protein interaction mechanism for PLA$_2$ inhibition by annexin I.I.

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다발성 후하소뇌동맥 해리성 동맥류 - 증 례 보 고 - (Multiple Dissecting Aneurysms of the PICA Trunk - Case Report -)

  • 김종태;김한규
    • Journal of Korean Neurosurgical Society
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    • 제30권1호
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    • pp.66-72
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    • 2001
  • Apatient with multiple dissecting aneurysms of a posterior inferior cerebellar artery trunk who presented with SAH is reported. A 58-year-old woman presented with sudden occipital headache, dizziness and vomiting. The intial vertebral angiography revealed a suspicious pearl and string sign at the proximal posterior inferior cerebellar artery(PICA) segment. After 2 weeks, follow up angiography showed a progression of the proximal PICA dissection and newly developed dissecting aneurysm of the distal PICA segment. A far lateral suboccipital transcondylar appoach confirmed two dissecting aneurysms at distant sites of the PICA trunk. The dissection segments were wrapped with muslin wrap, which preserved the flow through the PICA and brain stem perforators. The angiographys at 3 weeks and 6 months after operation revealed serial disappearance of the dissecting aneurysms which is distal to proximal. The diagnosis, course and treatment of the dissecting aneurysms of the PICA are discussed with literature review.

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탈피 탈지 대두분 식이가 흰쥐에서 식후 Lipid Profile과 효소, 호르몬 농도에 미치는영향 (Effectso f Dehulled Defatted Soy Flour on Postprandial Lipid Profile and Enzyme and Hormone Levels in Rats)

  • 한정희
    • Journal of Nutrition and Health
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    • 제31권2호
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    • pp.135-142
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    • 1998
  • This study was undertaken to determine whether dehulled defatted flour has an effect on postprandial plasma lipoprotein composition, hepatic lipid composition, enzyme and hormone levels in rats. Control(casein) and experimental (dehulled defatted soy flour)diets were fed to rats for 7 weeks. all animals (S. D. rats, male) were sacrificed 2 hrs after the feeding of 5g of each diet. Defatted soy flour feeding significantly lowered postprandial plasma total cholesterol, chylomicron/VLDL-cholesterol, hepatic cholesterol and triglyceride(TG) as compared with casein feeding, whereas no significant effect on plasma TG was observed. Intestinal kipase activity was elevated , whereas trypsin activity was suppressed in the dehulled defatted soy flour group. Plasma glucagon, thyroid hormone and hepatic HMG-coA reductase levels were not affected by diet treatment. These results hypothesize that dehulled defatted soy flour affects cholesterol digestion and absorption in guts, thus delaying the appearance of chylomicron cholesterol in plasma or affecting the disappearance of chylomicron remnant to high-density-lipoprotein(HDL).

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실내디자인과 현대미술의 상관적 표현성에 관한 연구 (A Study on the Relative Expresisons Between Interior Design and the Contemporary Art)

  • 박진배;이용완
    • 한국실내디자인학회논문집
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    • 제10호
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    • pp.50-57
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    • 1997
  • This study is concentrated on the specified relationship between the contemporary art and the interior design by investigation their situational connections through the expresison of their works. Each fields of modern art makes expressive situation more complicated and transforms its unintelligible and expressive outputs variously. The expression is the basis of the incompatibility of the modern art which features the ambivalence of the various tendency and the characteristics of the artists works as well as the disappearance of the typical genre of the art. The new expression such as the spatial recognition of the paintings and the participatio of the real, expreimental examples of the modern art enlarges its realm. The field interior design which has the close relationship with the fine arts need to make a new discussion or a theory among the progressive expression and the various tendencies of the art. Through this research, by reviewing the intermixed and expressed features of the artists works and designers projects which went far beyond the concepts and genre, the interrelationship between expression tendency of the contemporary art and the interior design has been specified.

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SUP9 스프링강의 숏피닝가공에 의한 피로수명향상과 고온환경에서의 압축잔류응력 소멸현상에 관한 연구 (A Study of Shot Peened Spring Steel(SUP9) for Fatigue Life Improvement and Compressive Residual Stress Disappearance on the High Temperature)

  • 박경동;손명균
    • 한국기계가공학회지
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    • 제2권1호
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    • pp.22-31
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    • 2003
  • The compressive residual stress, which is induced by shot peening process, seems to be an Important factor in increasing the fatigue strength. And then it was showed that residual stress was disappearenced at the high temperature. The fatigue charateristic investigation of a SUP9 spring steel processed shot peening is performed by considering the high temperature service conditions in the range of room temperature through $180^{\circ}C$ in the range of stress ratio of 0.3 by means of opening mode displacement. The fatigue resistance characteristics and fracture strength at high temperature is considerable lower than that of room temperature in the early stage and stable of fatigue crack growth region.

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