• Title/Summary/Keyword: VON

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

  • Yoo, Joo-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.2
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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).

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

  • Lee Hae-Yun
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.4
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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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    • v.54 no.5
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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.

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

  • Kim, Un-Young
    • Journal of the Korean Chemical Society
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    • v.14 no.1
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    • pp.19-27
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    • 1970
  • Durch Umsetzung von vernetzten p-jodstyrolhaltigen Coplymeren mit benzolischer Butyllithiumlosung und durch anschließende Carboxylierung mit gasformigem Kohlendioxid lassen sich p-carboxystyrolhaltige Copolymere herstellen. Die erreichbare Kapazitat der erhaltenen Harze betragt etwa 2,5 bis 2,8 mval/g. Aus den Titrations-nskurven erhahlt man einen scheinbaren $pK_a$-Wert von 8,07 fur das normal hergestellte und von 7,75 fur das toluolmodifizierte Harz. Der Austauscher nimmt Kaliumoinen im alkalischen Gebiet auf. Das Gleichgewicht des Harzes mit Calciumionen stellt sich bei pH = 6 bei ca. 85% Austausch ein. Dagegen nimmt das Harz Kupferionen bei pH = 4 bis 5 in der Außenlosung bis zu 100% auf.

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19세기 기하학에서의 ‘허’이론

  • 한경혜
    • Journal for History of Mathematics
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    • v.15 no.2
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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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    • v.33 no.1
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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
    • Journal of Biomedical Engineering Research
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    • v.19 no.1
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    • pp.53-58
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    • 1998
  • This study examined the distribution of bone mineral density(BMD) and the von Mises stress in the patella. The BMD of eighteen patellae were determined by using quantitative computed tomography and imaging analysis software. It was found that the BMD of the patella varied with location. BMD values were largest at the superior and lateral regions and decreased inferiorly and medially. This distribution appeared to correspond to the organization of trabeculae within the patella. A two-dimensional finite element analysis was performed on each patella. It was also found that the maximum von Mises stress in the patella occurred along the cortical shell on the non-articular surface. The trabecular von Mises stress existed in the posterior region of the patella. These findings demonstrated the potential for finite element studies in vivo. Further, such studies may lead to the development of custom-made, patient-specific patella prostheses.

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