• 제목/요약/키워드: Kondo

검색결과 120건 처리시간 0.025초

Direct Simulations of Aerodynamic Sounds by the Finite Difference and Finite Volume Lattice Boltzmann Methods

  • Tsutahara, Michihisa;Tamura, Akinori;Motizuki, Kazumasa;Kondo, Takamasa
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2006년도 추계 학술대회논문집
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    • pp.22-25
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    • 2006
  • Direct simulations of aerodynamic sound, especially sound emitted by rapidly rotating elliptic cylinder by the finite difference lattice Boltzmann method (FDLBM). Effect of pile-fabrics for noise reduction is also studied by the finite volume LBM (FVLBM) using an unstructured grid. Second order time integration and third order upwind scheme are shown to be enough for these simulations. Sound sources are detected to be doublets for both cases. For the elliptic cylinder, the doublet is generated in the interaction between the vortex and the edge. For the circular cylinders, they are generated synchronizing with the Karman vortex street, and it is also shown that the pile-fabrics covering the surface of the cylinder reduces the strength of the source.

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EFFECT OF KOREAN RED GINSENG ON EICOSANOID BIOSYNTHESIS IN PLATELETS AND VASCULAR SMOOTH MUSCLE CELLS

  • Tamura Y.;Hirai A.;Terano T.;Tahara K.;Saitoh J.;Kondo S.;Samukawa K.;Yoshida S.
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1993년도 학술대회지
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    • pp.28-29
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    • 1993
  • From in vivo and in vitro experiments using Korean Red Ginseng and its main components. ginsenoside saponins, it was found that ginesenoside may exerts its anti-thrombotic action by decreasing $TXA_2$ formation in platelets and increasing $PGI_2$ formation in vascular walls. This may certainly contribute to prevention and development of atherosclerosis and thrombosis by administration of Korean Red Ginsengs.

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CALPUFF 모델을 이용한 울산지역의 고농도 SO$_2$ 수치모의 (Numerical Simulation of High SO$_2$ Concentration Using CALPUFF in Ulsan Metropolitan City)

  • 김유근;임윤규;이평근;이영미
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2003년도 추계학술대회 논문집
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    • pp.520-521
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    • 2003
  • 우리나라의 대표적인 대기오염물질의 하나인 SO$_2$는 국가정책의 일환으로 지속적인 단속과 규제로 인해 꾸준히 감소하는 추세이다. 하지만, 연안공업도시인 울산지역의 경우 SO$_2$의 농도가 다른 지역에 비해 상대적으로 높게 나타나 여전히 문제가 되고 있는 실정이다. 울산지역에서 SO$_2$고농도 현상이 빈번히 발생하는 이유로, 도시를 감싸고 있는 산들과 많은 산업시설 및 도시빌딩으로 인해 복잡 지형의 형태를 가지고 있으며 특히, 인근 해양의 영향과 함께 나타나는 뚜렷한 국지기후 특성 등을 들 수 있다(Kondo et al., 1979; Entwistle, 1997).(중략)

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Using Animation Database Interactively on the Network

  • Tam, K.Y.;Sato, H.;Kondo, K.;Shimada, S.
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
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    • pp.7-12
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    • 1996
  • This research is on an interactive animation prototype which can be used by many users from different computers, that means a network with one server and many clients. In our research, a complete motion is represented by simple motion characteristics. We establish databases which contain all kinds of human motion characteristics. Using flexible connection and appropriate time control, we are able to recompose a sequential serial motion data. Moreover, an interactive application system is needed among the uses with a server from animator. In this research, we also investigate three methods of“connect motion database”. We are planing to use the method of connecting motion database under networks with a client-server application system.

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Multifunctionality in Ceramic/Metal Nanocomposites

  • Sekino, Tohru;Kondo, Hiroki;Niihara, Koichi
    • 한국분말재료학회지
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    • 제8권3호
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    • pp.186-191
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    • 2001
  • Several fabrication processes, corresponding nanostructural features and multifunctionality as well has been investigated for oxide ceramic based nanocomposites with metal nanodispersion (i.e., ceramic/metal nanocomposites). Transition metal (Ni, Co, etc) dispersed alumina and zirconia based nanocomposites have been synthesized by reducing and hot-press sintering of ceramic and metal oxide mixtures prepared by several method. Improved fracture strength (1.1 and 1.9 GPa for $Al_2O_3/Ni$ and $ZrO_2/Ni$ nanocomposites, respectively) of these composites have been achieved according to their nanostructures. In addition, ferromagnetic characteristic has been kept. The variation of magnetization with an applied stress has found to be more sensitive as smaller as the magnetic metal dispersion is. This result thus suggests the possibility of fracture and/or stress sensing of the composites by simple magnetic measurement.

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Permeability imaging in granitic rocks based on surface resistivity profiling

  • Sudo Hiroshi;Tanaka Toshikazu;Kobayashi Tsuyoshi;Kondo Tatsutoshi;Takahashi Toru;Miyamoto Masaharu;Amagai Mitsuru
    • 지구물리와물리탐사
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    • 제7권1호
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    • pp.56-61
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    • 2004
  • In order to image the distribution of permeability in granitic rocks, we carried out two-dimensional (2D) resistivity profiling, together with in-situ permeability tests, electrical logging of boreholes, and resistivity measurements of rock core samples in a laboratory. Based on the electrical logging and in-situ permeability data from boreholes, we obtained empirical equations which relate resistivity and permeability of the granitic rocks in the area studied. We then applied the empirical equation to a 2D resistivity section, to produce a 2D permeability section of the granitic rocks. In this paper, we present details of the field data and of the procedure for conversion from the resistivity section to a permeability section. The observed relationship between resistivity and permeability of the rocks is also discussed.

Numerical Simulation of Environmental Pollutants at Yosu, Korea and Comparison with Measured Data

  • Lee, S. D.;A. Kondo;K. Yoshimura;K. Yamaguchi;A. Kaga
    • Journal of Korean Society for Atmospheric Environment
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    • 제19권E2호
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    • pp.63-73
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    • 2003
  • The atmospheric pollution distribution in the industrial area of Yosu in Korea is calculated using numerical model and the model is validated by comparing the calculations with observed data. The emission of NO$_{x}$ and SO$_{x}$ was estimated for 6 sources, and the emission amount of HC was estimated for 9 anthropogenic sources. The calculated wind speed, wind direction and temperature agreed well with the observed data at two observatories, and the calculated concentration of NO, NO$_2$, $O_3$ and SO$_2$ were also reasonable for 5 monitoring stations. The validity of the model is evaluated using 3 indexes of the EPA, and the model is found to be valid and accurate.ate.

The Numerical Prediction of the Micro Climate Change by a Residential Development Region

  • Oh, Eun-Joo;Lee, Hwa Woon;Kondo, Akira;Kaga, Akikazu;Yamaguchi, Katsuhito
    • 한국환경과학회지
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    • 제12권5호
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    • pp.529-539
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    • 2003
  • We developed a numerical model that considered the influences on the thermal environment of vegetation, water surfaces and buildings to predict micro climatic changes in a few $\textrm{km}^2$ scales; and applied this model to the Mino residential development region in Osaka Prefecture by using a nested technique. The calculated temperatures and winds in the residential development region reasonably agreed with the observed ones. We then investigated the influences on the thermal environment of the construction of a dam, the change of the green coverage rate. The results obtained from the numerical simulations were qualitatively reasonable.