• 제목/요약/키워드: projection Method

검색결과 1,548건 처리시간 0.032초

라디에이터 통과풍량 확보를 위한 수치적 검토 (Numerical Analysis for Improving Passing Flow Rate Quantity abound a Radiator)

  • 김은필;강상훈
    • Journal of Advanced Marine Engineering and Technology
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    • 제25권2호
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    • pp.304-310
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    • 2001
  • This paper describes the analysis of flow field using a projection finite element method. The projection scheme with a pressure correction is presented for the analysis of an incompressible Navier-Stokes flow. The projection scheme is analyzed numerically and applied to the well-known bench marking problems such as lid driven cavity. Finally, the projection scheme is applied to a flow through the automobiles front. In the automobiles cooling system, the flow through its front is very important to a cooling performance. The results show that the flow quantity increases by locating the position of bumper to the further front position of a car. And, the improvement on the suction part below a bumper achieves the more passing flow quantity. The attachment of an air dam increases passing flow quantity causing the pressure rise to the front part and the pressure drop beneath a car.

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3투사렌즈방식 LCD 프로젝션 TV의 엔진 냉각에 관한 연구 (A study on the cooling method for LCD projection TV with 3 projection lens)

  • 김철환;조여욱
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1253-1257
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    • 2004
  • We have developed new rear LCD Projection TV engine with 3 projection lens. It has high brightness and contrast ratio, however poor cooling conditions. If optical components close to light source, optical components are damaged on high temperature, especially the blue among RGB colors is weakest by heat In this study, a new enhanced cooling method of LCD projection TV with 3 lens is shown: the best suited design of duct and relations between LCD panel and polarizer lifetime with changed area of duct.

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사장석(斜長石)을 포함(包含)한 복수투영(複數投影)에 있어서의 행렬식(行列式) 이용(利用)에 관(關)한 연구(硏究) (Matrix Method in Multiple Projection through Plagioclase)

  • 이상헌
    • 자원환경지질
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    • 제17권4호
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    • pp.283-288
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    • 1984
  • Projection method has been used in the phase equilibria study. The projection is made through the saturated phase on the smaller chemical system from larger system. This decreases the number of phases which are included in the larger chemical system. In multiple projection containing plagioclase as a projection phase, there is a difference in matrix calculation when plagioclase is treated as a single composite component and separately as an albite and anorthite. The matrix calculation is considered to be more usable and easier in multiple projection. The value of the A component in the AFM system, which is the smaller system projected from the larger one, is effected and varies according to the change in the An content in plagioclase that is examined as an example.

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주거용 건물에서의 투영법에 의한 조망의 정량적 분석에 관한 연구 (A Study on the Quantitative Analysis of View by the Projection Method in the Residential Buildings)

  • 김용이;김광우
    • 한국주거학회논문집
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    • 제14권5호
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    • pp.37-46
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    • 2003
  • The quantitative analysis of view tells how surroundings and sky are showed, and requires understanding of visual perception and three dimensional information of buildings. The visual perception and the existing projection methods for view analysis are examined. The results of this study are as follows: The visual perception on the size is determined by the visual angle, which can be described as a solid angle. The analysis of view by planar projection can be narrow-sighted according to the size of the window and the location of the viewpoint, which will cause the obstacles in the normal direction of the window interfere the view. For the analysis of view by fisheye projection, the area around the focus point is calculated wider than other areas, and so the view ratio depends on the position of the focus point. When analyzing sky view by dividing the sky vault into the differential area, the distortion by projection can be minimized.

히스토그램 프로젝션을 이용한 움직이는 카메라로 부터의 이동물체 추적 알고리즘 (Algorithm for Moving Object Tracking from Moving Camera Using Histogram Projection)

  • 설성욱;이희봉;김효성;남기곤;이철헌
    • 융합신호처리학회논문지
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    • 제2권4호
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    • pp.38-45
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    • 2001
  • 본 논문에서는 히스트로그램 백 프로제션(HBP: histogram back projection); 히스트로그램 인터섹션(HI:histogram intersection )그리고 XY-프로젝션(XY-projectipn)을 이용하여 움직이는 카메라로부터 이동 물체를 추적하는 알고리즘을 제안하였다. 제안된 방법은 히스토그램 백 프로젝션을 이용하여 물체를 분할하고 히스토그램 인터섹션과 XY-프로젝션을 사용하여 추적물체를 정합하고 추출하였다. 본 논문에서는 컴퓨터 모의 실험을 통하여 제안된 방법이 움직이는 카메라로부터 획득된 영상에서 추적하고자 하는 물체를 분할하고 정합하여 큰 오차 없이 추적함을 보였다.

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Inactive Regions Padding Methods for Rotated Sphere Projection of 360 Video

  • Yoon, Yong-Uk;Kim, Hyun-Ho;Kim, Jae-Gon
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2018년도 하계학술대회
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    • pp.200-201
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    • 2018
  • In the workflow of 360 video coding of JVET (Joint Video Experts Team), firstly the 360 videos are projected onto the 2D plane with diverse projection formats, such as Equi-Rectangular Projection (ERP), Cubemap Projection (CMP), Rotated Sphere Projection (RSP), etc. The projection format of RSP has inactive regions in the converted 2D plane. The inactive regions may cause visual artifact as well as the reduction of the coding efficiency due to discontinuity at boundaries between active and inactive regions. In this paper, to overcome these problems, the inactive regions are padded by using two types of adjacent pixels. Then padded regions of RSP are blended with inactive regions padded by proposed method. The experimental results demonstrate that, in terms of end-to-end WS-PSNR-NN, the proposed method achieves 0.1% BD-rate reduction. In addition, the visual artifacts along the borders between discontinuous faces are noticeably reduced.

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인체형상 측정을 위한 가상격자 영사식 무아레 방법에 관한 연구 (A Study on the Virtual Grating Projection Moire Topography for the Shape Measurement of Human Face)

  • 유원재;최정표;안중근;강영준
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.49-52
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    • 2001
  • Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topogrphy is very attractive because of it s high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the $2\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the $2\pi$-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

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THE ITERATED PROJECTION METHOD FOR INTEGRO-DIFFERENTIAL EQUATIONS WITH CAUCHY KERNEL

  • Mennouni, Abdelaziz
    • Journal of applied mathematics & informatics
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    • 제31권5_6호
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    • pp.661-667
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    • 2013
  • In this paper we propose the iterated projection method for the approximate solution of an integro-differential equations with Cauchy kernel in $L^2([-1,1],\mathbb{C})$ using Legendre polynomials. We prove the convergence of the method. A system of linear equations is to be solved. Numerical examples illustrate the theoretical results.

NUMERICAL PROPERTIES OF GAUGE METHOD FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS

  • Pyo, Jae-Hong
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제14권1호
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    • pp.43-56
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    • 2010
  • The representative numerical algorithms to solve the time dependent Navier-Stokes equations are projection type methods. Lots of projection schemes have been developed to find more accurate solutions. But most of projection methods [4, 11] suffer from inconsistency and requesting unknown datum. E and Liu in [5] constructed the gauge method which splits the velocity $u=a+{\nabla}{\phi}$ to make consistent and to replace requesting of the unknown values to known datum of non-physical variables a and ${\phi}$. The errors are evaluated in [9]. But gauge method is not still obvious to find out suitable combination of discrete finite element spaces and to compute boundary derivative of the gauge variable ${\phi}$. In this paper, we define 4 gauge algorithms via combining both 2 decomposition operators and 2 boundary conditions. And we derive variational derivative on boundary and analyze numerical results of 4 gauge algorithms in various discrete spaces combinations to search right discrete space relation.

디지털 영사식 무아레를 이용한 3차원 형상 측정과 응용에 관한 연구( I ) (A Study on 3-D Shape Measurement and Application by using Digital Projection $Moir\acute{e}$ ( I ))

  • 유원재;노형민;이동환;강영준
    • 한국정밀공학회지
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    • 제22권7호
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    • pp.88-93
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    • 2005
  • $Moir\acute{e}$ topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by $Moir\acute{e}$ topography has been required, since the method was frequently applied to the engineering and medical fields. The 3-D measurement using projection $Moir\acute{e}$ topography is very attractive because of its high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection $Moir\acute{e}$ topography was tested to measuring object with $2\pi-ambiguity$ problems. The experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the $2\pi-ambiguity$ problems can be effectively overcome so as to treat large step discontinuities in measured objects.