• 제목/요약/키워드: VON

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Von-Kármán 회전 유동 하에서의 액체 실리콘의 응고와 열전달 (Heat Transfer and Solidification of Liquid Silicon in von-Kármán Swirling Flow)

  • 유주식
    • 대한기계학회논문집B
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    • 제23권2호
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    • pp.185-197
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    • 1999
  • Heat transfer and solidification of liquid silicon in von-$K{\acute{a}}rm{\acute{a}}n$ swirling flow is investigated. The moving boundary is fixed for all times by a coordinate transformation, and finite difference method Is used to obtain the instantaneous location of the solid-liquid Interface and the heat transfer from the surfaces of solid and liquid. For small Stefan number or low wall temperature, the transient heat transfer from the surface of solid(QS(t)) is much larger than that from the liquid side of solid-liquid interface(QL(t)) and QL(t) reaches its quasi-steady-state value much faster than QS(t).

담화의 구조 - 새로운 담화문법의 설계 (Die Analysen von Diskursstrukturen anhand einer neuen Diskursgrammatik)

  • 이해윤
    • 한국독어학회지:독어학
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    • 제4집
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    • pp.109-128
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    • 2001
  • Bei vorliegender Arbeit wurde eine sogenannte Diskursstrukturgrammatik (DSG) vorgestellt, die auf die $Erkl\"{a}rung$ von verschiedenen diskursbezogenen $Ph\"{a}nomenen$ zielt, und derer Grundlage auf 'Head-driven Phrase Structure Grammar (HPSG)' basiert. Im Abschnitt 2 wurde die Syntax von DSG gegeben. Die Syntax besteht aus Grundsymbolen und Regeln. Die Grundsymbole teilen sich wiederum in grundlegende Diskurseinheiten und logische Konnektoren ein. Entsprechend der Syntax wurde die Semantik im Abschnitt 3 gegeben. Insbesondere habe ich das Diskursrelation­Prinzip aufgestellt, nach dem die Information eines Konnektoren die Bedeutung der neu gebildeten Diskurseinheit bestimmt. Im letzten Abschnitt 4 habe ich anhand der DSG zwei Beispiele analysiert, um zu zeigen, wie die DSG funktioniert. Von der Theorie aus gesehen, ist die vorgestellte DSG nicht $vollst\"{a}ndig$. Deshalb werde ich weiter die DSG systematisieren, indem ich andere $Ph\"{a}nomene$ im Bereich des Diskurses wie Anapher, Tempus usw. behandle

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Meningeal Supratentorial Hemangioblastoma in a Patient with Von Hippel-Lindau Disease Mimicking Angioblastic Menigioma

  • Kim, Hoon;Park, Ik-Seong;Jo, Kwang-Wook
    • Journal of Korean Neurosurgical Society
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    • 제54권5호
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    • pp.415-419
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    • 2013
  • Hemangioblastomas are sporadic tumors found in the cerebellum or spinal cord. Supratentorial hemangioblastomas are rare, and those with meningeal involvement are extremely rare and have been reported in only approximately 130 patients. Here, we report the case of a 51-year-old female patient with supratentorial meningeal hemangioblastoma detected 5 years after surgical resection of an infratentorial hemangioblastoma associated with von Hippel-Lindau disease. Patients with von Hippel-Lindau syndrome are at risk for developing multiple hemangioblastomas, with new tumor formation and growth and possible meningeal infiltration. Regular lifelong follow-up in at-risk patients is recommended and should include the differential diagnosis of dural-based tumors such as angioblastic meningioma and metastatic renal cell carcinoma.

p-Carboxystyrol계 양이온 교환 수지 (Kationenaustauscher auf Basis von p-carboxystyrolhaltigen Copolymeren)

  • 김은영
    • 대한화학회지
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    • 제14권1호
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    • pp.19-27
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    • 1970
  • 가교되고 p-요드스티롤을 함유한 공중합체를 부틸리티움 벤젠용액과 반응시키고 이어 이산화탄소와 반응시키면 p-카복시티롤을 갖는 공중합체를 얻을 수 있다. 이 수지로 얻을 수 있는 이온 교환능력은 2.5∼2.8mval/g이다. 그리고 중화곡선으로부터 얻은 $pK_a$치는 보통 수지의 경우 8.07, 톨루엔으로 변성한 수지는 7.75이다. 이 수지는 알칼리성에서 칼리움 이온을 받아들이고, 칼시움 이온과는 $pH^{-6}$에서 85%, 구리 이온과는 pH4-5에서 100% 각각 교환 반응을 일으킨다.

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19세기 기하학에서의 ‘허’이론

  • 한경혜
    • 한국수학사학회지
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    • 제15권2호
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    • pp.15-32
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    • 2002
  • The first part of this thesis gives some brief explanation of the theory and history of imaginary elements in analytic geometry in the 19th century. The second part of this thesis discusses the theory of imaginary elements of synthetic geometry in the first half of the 19th century. Then the next part mentions the theory of imaginary elements of geometry in the second half of that same century. Particularly Christian von Staudt's and Felix Klein's theories are handled in this part. Von Staudt, who has completed the system of the synthetic projective geometry, used ‘involution’ in order to introduce a new concept ‘imaginary elements’- imaginary points, imaginary lines and imaginary plane-in synthetic geometry. Klein applied von Staudt's theory as he convey the result of the research in algebraic geometry in a picture. Von Staudt's and Klein's research may be regarded as the top of the effort to investigate possible relationship between real and imaginary structures.

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Distribution of Taste Receptors in Submandibular and von Ebner Salivary Glands

  • Jun, Yong-Ku;Kim, Se-Nyun;Lee, Cil-Han;Cho, Young-Kyung;Chung, Ki-Myung;Roper, Stephen D.;Kim, Kyung-Nyun
    • International Journal of Oral Biology
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    • 제33권1호
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    • pp.13-23
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    • 2008
  • Taste is a critically important sense for the survival of an organism. However, structure and distribution of taste receptors were only recently investigated. Although expression of the ion channels responsible for the sense of salty taste and acidity was observed in the non-taste cells, receptors for sweet and bitter taste were only identified in taste cells. Salivary glands are involved in the sensing of taste and plays important roles in the transduction of taste. The purpose of this study is to examine whether taste receptors are present in the salivary glands and to provide clues for the investigation of the taste-salivary glands interaction. Using microarray and RT-PCR analyses, the presence of taste receptor mRNAs in the rat von Ebner gland and submandibular gland was confirmed. Type I taste receptors were preferentially expressed in von Ebner gland, whereas type II taste receptors were expressed in both von Ebner gland and submandibular gland. The tastespecific signal tranducing proteins, $G_{\alpha}gustducin$ and phospholipase C ${\beta}2$, were also detected in both salivary glands by immunohistochemistry. Finally, the activation of the calcium signal in response to bitter taste in the acinar cells was also observed. Taken together, these results suggest that taste receptors are present in the von Ebner gland and submandibular gland and that type II taste receptors are functionally active in both salivary glands.

Bone Mineral Density and Stress Distribution in Human Patella

  • Han, Seung-Moo;Jared Davis
    • 대한의용생체공학회:의공학회지
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    • 제19권1호
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    • pp.53-58
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    • 1998
  • 본 연구에서는 슬개골의 골밀도와 Von Mises 응력의 분포를 조사하였다. 18개 슬개골의 골밀도는 컴퓨터 단층촬영과 영상분석 소프트웨어를 사용하여 결정하였다. 슬개골의 골밀도는 위치에 따라 변화됨을 발견하였다. 골밀도값은 상외측부에서 가장 크고 아래쪽 혹은 내쪽으로 갈수록 감소하였다. 이 분포는 슬개골 안에서 소주의 조직과 일치됨을 보였다. 각 슬개골에서 2차원 유한요소법을 실행한 결과 슬개골의 최대 Von Mises응력은 비관절 표면 위에 있는 피질외피에 따라 발생하였다. 소주의 최대 Von Mises응력은 슬개골의 후방부에 존재했다. 이 발견들은 생체내의 유한요소 연구에 대한 잠재적 가능성을 증명하였다. 따라서 이러한 연구들은 주문형, 환자특성에 맞는 슬개골 인공보철물들의 개발을 유도할 수 있게 한다.

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