• Title/Summary/Keyword: oval weighting

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Development of the Best Spherical Interpolation Method for Estimating Potential Natural Vegetation Distribution of the Globe (지구(地球)의 잠재자연식생분포(潜在自然植生分布)를 추정(推定)하기 위한 최적구면보간법(最適球面補間法)의 개발(開發))

  • Cha, Gyung Soo;Ochiai, Kamiya
    • Journal of Korean Society of Forest Science
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    • v.86 no.1
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    • pp.17-24
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    • 1997
  • As the first step to estimate the potential natural vegetation distribution of the globe, the best spherical interpolation method was developed to the temperature and precipitation which have close relation to the distribution pattern of world natural vegetation. For developing the interpolation method, a named Light Climatic Dataset composed of 1,060 stations around the globe was randomly divided into halves of feeding side and target side. The discrepancy between the observed and estimated values at the target stations was compared with combinations of parameters and methods. The estimated values were calculated to each combination which is all-out, constant radius and constant station methods in the selection of the feeding stations, n square reciprocal and negative exponential functions in weighting function of distance between feeding stations and each target, and oval weighting in direction of the feeding stations from each target. As a result, it turned out that the spherical interpolation with negative exponential weighting function fed from the constant radius stations ovally weighed yields the best estimates both for temperature and for precipitation. The parameters for temperature are $30^{\circ}$ in constant radius, 0.78 in negative exponential function and 0.4 in oval weighting, and for precipitation are $30^{\circ}$, 0.53 and 0.4, respectively.

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Prediction Model of the Exit Cross Scetional Shape in Round-Oval -round Pass Rolling

  • Lee, Young seog;Gert Goldhahn
    • International Journal of Precision Engineering and Manufacturing
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    • v.2 no.1
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    • pp.87-93
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    • 2001
  • A reliable analytic model that determines the exit cross sectional shape a workpiece(material) in round-oval (oroval-round) pass sequence has been developed. The exit cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groovw to the roll axis direction. The requirements placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by not rod rolling experiment with the roll gap and specimen size changed. The exit cross sectional shape and area of the workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. We found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

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Prediction of Stress Free Surface Profile of Wrokpiece in Rod Rolling Process (선재압연공정의 소재 자유표면 형상예측)

  • Lee, Youngseog;Kim, Young-Ho;Jin, Young-Eun
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.9
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    • pp.174-180
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    • 2000
  • A reliable analytic model that determines the cross sectional shape of a workpiece(material) in round-oval(or oval-round) pass sequence has been developed. the cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groove to the roll axis direction. The requirements we placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by hot rod rolling experiment with the roll gap and specimen size changed. The cross sectional shape and area of a workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. It was found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

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Multilobular Tumor of Skull in a Maltese Dog (말티즈 견의 두개골에서 발생한 다엽성 종양)

  • Yang, Cheol-ho;Kang, Min-hee;Kim, Seung-gon
    • Journal of Veterinary Clinics
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    • v.33 no.1
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    • pp.48-50
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    • 2016
  • A 10-year-old spayed female Maltese dog weighting 3.4 kg was referred with growing firm mass at the parietal bone region from 2 weeks ago. A firm, partially calcified mass ($1.9cm{\times}4.4cm$) was palpated in the region of the frontal and parietal skulls but had no neurologic signs. Computed tomography (CT) characteristics of mass were round to oval shape, fine granular appearance, and well defined margins. Mass involving the calvarial bones had invasion into the cranial vault with a significant intracranial portion. Histologically, the tumor was characterized by the presence of multiple lobules containing osteoid or cartilage in the center that were separated by anastomosing fibrous septae. This is case report described the clinical and histopathological features of multilobular tumor of skull in a Maltese dog.