• Title/Summary/Keyword: cross section area

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Morphometrical Differences between Diploid and Induced Triploid Cherry Salmon, Oncorhynchus masou (산천어, Oncorhynchus masou 2배체와 유도 3배체의 형태학적 차이)

  • Park, In-Seok;Zhang, Chang-Ik
    • Korean Journal of Ichthyology
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    • v.6 no.2
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    • pp.206-221
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    • 1994
  • Morphometrical data for diploid and induced triploid cherry salmon, Oncorhynchus masou were analyzed prior to the spawning season to compare their commercial values. The following traits were measured with the diploids and induced triploids : ungutted and gutted body weight; body length; dressing percentage; condition factor; gonad weight and gonad index; belly thickness; viscera weight; viscera index; body circumference at the pelvic, dorsal and anal fins; area of the cross sections at the pelvic and dorsal fins; two belly thickness traits measured on each cross section; total height, height and width of each cross section; three body shape traits; and nine cross section shape traits. Body length and body weight of diploids were larger than those of induced triploids and dressing percentage, gonad weight, gonad index, viscera index, and liver index were also larger in diploids. However, induced triploids showed higher values in one belly thickness trait and some section shapes than diploids. Differences in body traits were due to the sterility of induced triploids. Therefore, induced triploid cherry salmon appears to have greater potentials for the commercial values than their diploids.

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Resonant Transmission through C-Shaped and H-Shaped Small Apertures and the Mutual Coupling Effect between Two C-Shaped Apertures (C-형태와 H-형태의 소형 개구에 의한 공진 투과 및 C-형태 개구 간의 상호 결합 효과)

  • Ko, Ji-Hwan;Cho, Young-Ki
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.12
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    • pp.1399-1405
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    • 2012
  • Transmission cross section characteristics as a measure of transmission efficiency has been analyzed numerically for the H-shaped and C-shaped small apertures in the infinite conducting plane when illuminated by a plane wave. It has been found that C-shaped aperture has the larger transmission cross section than that of H-shaped aperture under the condition of the same perforated aperture area. Main attention has been focused on studying the mutual coupling effect between two C-shaped apertures on the transmission cross section characteristic. Parallel configuration which is composed of two C-shaped apertures arranged along the x-axis and collinear configuration which is composed of two C-shaped arrayed along the y-axis have been investigated from the viewpoint of enhanced transmission cross section characteristics.

New Approach for Nonlinear Analysis of Reinforced Concrete Frames (철근콘크리트 골조 비선형해석의 새로운 기법)

  • 김진근;이태규;양주경
    • Proceedings of the Korea Concrete Institute Conference
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    • 1992.04a
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    • pp.47-52
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    • 1992
  • The entire nonlinear behavior of reinforced concrete frames up to collapse, is analyzed by the displacement control method and the combined layered and nonlayered method. All of the rigidities of section are calculated approximately by a sum over all the layers for the layered method, are used the integral values over the cross section area for the nonlayered method. The spurious sensitivity to the chosen element size in the result of analysis by finite element method for the materials with strain-softening can be overcome by modifying the strain distribution based on the concept of fracture energy at plastic hinge considering the applied axial load.

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Finite element analysis of the fluid-structure interaction in a compliant vessel (유연 혈관에서 유체-고체 상호작용에 대한 유한요소 해석)

  • Shim, Eun-Bo;Ko, Hyung-Jong;Kamm, Roger D.
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.591-596
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    • 2000
  • Flow through compliant tubes with linear taper in wall thickness is numerically simulated by finite element analysis. Two models are examined: a planar two-dimensional channel, and an axisymmetric tube. For verification of the numerical method, flow through a compliant stenotic vessel is simulated and compared to existing experimental data. Computational results for an axisymmetric tube show that as cross-sectional area falls with a reduction in downstream pressure, flow rate increases and reaches a maximum when the speed index (mean velocity divided by wave speed) is near unity at the point of minimum cross-section area, indicative of wave speed flow limitation or "choking" (flow speed equals wave speed) in previous one-dimensional studies. For further reductions in downstream pressure, flow rate decreases. Cross-sectional narrowing is significant but localized. When the ratio of downstream-to-upstream wall thickness is ${\le}$ 2 the area throat is located near the downstream end; as wall taper is increased to ${\ge}$ 3 the constriction moves to the upstream end of the tube. In the planar two-dimensional channel, area reduction and flow limitation are also observed when outlet pressure is decreased. In contrast to the axisymmetric case, however, the elastic wall in the two-dimensional channel forms a smooth concave surface with the area throat located near the mid-point of the elastic wall. Though flow rate reaches a maximum and then falls, the flow does not appear to be choked.

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Numerical Analysis on Strength of Interior Flat Plate-Column Connections according to Column Section Shape (기둥 단면형상에 따른 플랫플레이트-기둥 접합부 강도에 관한 수치해석연구)

  • Kang Su Min;Kim Oak Jong;Lee Do Bum;Park Hong Gun;Chun Young Soo;Lee Hyun Ho
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.291-294
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    • 2005
  • In the present study, a numerical analysis was performed for interior connections of continuous flat plate to analyze the effect of column section shape on the behavioral characteristics of the connections. For the purpose, a computer program for nonlinear FE analysis was developed, and the validity was verified. Through the parametric study, the variations of shear stress distribution around the connection were investigated. According to the result of numerical analysis, the column section shape has a serious effect on the behavior of the connections. As the length of the cross section of column in the direction of lateral load increases, the effective area and the shear strength at the sides providing the torsional resistance decrease considerably. Therefore the strength model for the flat plate-column connections should be modified by considering the effect of column section shape on the behavior of the connections.

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A Study on DEM-based Automatic Calculation of Earthwork Volume for BIM Application

  • Cho, Sun Il;Lim, Jae Hyoung;Lim, Soo Bong;Yun, Hee Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.38 no.2
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    • pp.131-140
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    • 2020
  • Recently the importance of BIM (Building Information Modeling) that enables 3D location-based design and construction work is being highlighted around the world. In Korea, the road map has been established to settle the design based on BIM using drone survey results by 2025. As the first step, BIM would be applied to road construction projects worth more than 50 billion Korean Won from 2020. On the other hand, drone survey regulation has been enacted and the data for drone survey cost were also included on Standard of construction estimate in 2020. However, more careful improvement is required to reflect drone survey results in BIM design and construction. Currently, Engineering instructions and Standard of construction estimate specifies that earthwork volume must be calculated by cross section method only. So it is required to add the method of DEM (Digital Elevation Model) based volume calculation on these regulations to realize BIM application. In order for that, this study verified the method of DEM based earthwork volume calculation. To get an accurate DEM for accurate volume computation, drone survey was carried out according to the drone survey regulation and then could get an accurate DEM data which have errors less than 3cm in X, Y and 6.8cm in H. As each DEM cell has 3D coordinate component, the volume of each cell can be calculated by obtaining the height of area of the cell then total volume is calculated by multiplying total number of cells by volume of each cell for the construction area. Verification for the new calculation method compare with existing method was carried out. The difference between DEM based volume by drone survey and cross section based volume by traditional survey was less than 1.33% and it can be seen that new DEM method will be able to be applied to BIM design and construction instead of cross section method.

Development of Radar Cross Section Analysis Program for Complex Structures (복합 구조물의 레이더 반사면적 해석 프로그램 개발)

  • Kwon, Hyun-Wung;Hong, Suk-Yoon;Song, Jee-Hun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.4
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    • pp.435-442
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    • 2014
  • In this paper, radar cross section (RCS) analysis program, RACSAN has been developed to predict RCS of complex structures. RACSAN is based on the high frequency range analysis method of Kirchhoff approximation in physical optics (PO). This program can present RCS including multi-bounce effect in complex structures by combination of geometric optics (GO) and PO method. GO method has a concern in the evaluation of the effective area, and PO method is involved in the calculation of RCS for the final effective area that is evaluated by GO method. Comparisons of the predicted results and analytical solutions showed that the developed program could be an effective tool for predicting RCS in complex structures.

THREE DIMENSIONAL RECONSTRUCTION OF TEETH USING X-RAY MICROTOMOGRAPHY (X-ray microtomography를 이용한 치아의 3차원 재구성)

  • Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.28 no.6
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    • pp.485-490
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    • 2003
  • Complete understanding of the exterior and interior structure of the tooth would be prerequisite to the successful clinical results, especially in the restorative and endodontic treatment. Although three-dimensional reconstruction method using x-ray microtomography could not be used in clinical cases, it may be the best way to reconstruct the morphologic characteristics of the tooth structure in detail without destructing the tooth itself. This study was done to three dimensionally reconstruct every teeth in the arch in order to increase the understanding about the endodontic treatment and to promote the effective restorative treatment by upgrading the knowledge of the tooth morphology. After placing tooth between the microfocus x-ray tube and the image intensifier to obtain two-dimensional images of each level. scanning was done under the condition of 80 keV, $100{\;}\mu\textrm{m}$, 16.8 magnification with the spot size of $8{\;}\mu\textrm{m}$. Cross-section pixel size of $16.28{\;}\mu\textrm{m}$ and 48.83 cross-section to cross-section distance were also used. From the results of this study, precise three dimensional reconstructed images of every teeth could be obtained. Furthermore, it was possible to see image that showed interested area only, for example. enamel portion only, pulp and dentin area without enamel structure, pulp only, combination image of enamel and pulp, etc. It was also possible to see transparent image without some part of tooth structure. This image might be used as a guide when restoring and preparing the full and partial crown by showing the positional and morphological relationship between the pulp and the outer tooth structure. Another profit may be related with the fact that it would promote the understanding of the interior structure by making observation of the auto-rotating image of AVI file from the various direction possible.

The Analysis of Flood in an Ungauged Watershed using Remotely Sensed and Geospatial Datasets (II) - Focus on Estimation of Flood Inundation - (원격탐사와 공간정보를 활용한 미계측 유역 홍수범람 해석에 관한 연구(II) - 침수 피해면적 산정을 중심으로 -)

  • Son, Ahlong;Kim, Jongpil
    • Korean Journal of Remote Sensing
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    • v.35 no.5_2
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    • pp.797-808
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    • 2019
  • This study evaluated the applicability of spacebourne datasets to the flood analysis in an ungauged watershed where is no discharge measurements. The Duman River basin of North Korea was selected as a target area which was flooded by recent Typhoon Lionrock. Topographical parameters for flood analysis were estimated from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM). GDEM includes the shortcomings of information on river cross-section, and conducted 2 dimensional flood analysis when considering virtual river cross-section and not considering it. As a result of comparative analysis, an error occurs in the inundation area and depth, but when used carefully, it is considered that the satellite image can be used for creating flood hazard map and utilizing information for response and preparation.

A New Experimental Method of Mechanical Analysis for Arterial Cross-Section Research (동맥 전단부의 역학적분석을 위한 새로운 실험적 방법)

  • 황민철;신정욱
    • Journal of Biomedical Engineering Research
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    • v.16 no.2
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    • pp.149-156
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    • 1995
  • This paper suggests a new experimental system and protocol of mechanical analysis for arterial cross-section research. So far, most methods of arterial studies have been focused on the deformation measurement in longitudinal and circumferential direction. The deformation in radial direction has been theoretically assumed by Poisson's ratio and/or the incompressibility of arterial wall. Also, the radial gradient of strains are neglected. In fact, the radial deformation and radial gradient of strains against blood pressure are important to be observed in the pathological point of view of artery. Proposed experimental system and protocol are to measure the deformation of cross-sectional artery. Also, this method enables to measure the deformation of anterior, posterior, and side site of cross-sectional area. It is meaningful to correlate the mechanically experimented data with pathological data of athroscIerotic artery.

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