• 제목/요약/키워드: The numerical method

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VE제안의 가치향상 유형별 수치적 범위기준 제시 (Numerical Range Criteria for Classification of Value Engineering Proposals based on Value Improvement Types)

  • 남경우;장명훈
    • 공학기술논문지
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    • 제11권4호
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    • pp.287-294
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    • 2018
  • Since its introduction in Korea, design VE has widely been used as a means to enhance values in the construction industry. However, a greater emphasis is still placed on cost reduction in approach attitudes and performance evaluations on the implementation of design VE. In this regard, this study presented a performance evaluation method for cost, function, and value of VE proposals. Numerical criteria on the increase and decrease of cost and function that can classify the value enhancement type of VE proposals were proposed based on the performance evaluation method. It is expected that the use of numerical criteria for the type classification of VE proposal, and cost and performance evaluation method proposed in this study will make it possible to conduct a clear and more intuitive evaluation of VE proposal. However, it is appropriate to use the numerical criteria as a guideline to apply the new performance evaluation method for VE proposals. Therefore, it is necessary to conduct a statistical analysis with a wider range of users after the repeated application of the findings of this study, and thus to carry out research for presenting the numerical criteria for various types of users.

층류 열성층유동 곡관에 대한 복합열전달 수치해석 (Numerical Analysis of Conjugate Heat Transfer in a Curved Piping System Subjected to Internal Stratified Laminar Flow)

  • 조종철;최훈기
    • 한국전산유체공학회지
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    • 제7권3호
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    • pp.35-43
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    • 2002
  • This paper addresses a numerical method for predicting transient temperature distributions in the wall of a curved pipe subjected to internal laminar thermally-stratified flow. A simple and convenient numerical method of treating the unsteady conjugate heat transfer in non-orthogonal coordinate systems is presented. Numerical calculations are performed for the transient evolution of thermal stratification in two curved pipes, where one has thick wall and the other has so thin wall that its presence can be negligible in the heat transfer analysis. The predicted results show that the thermally stratified flow and transient conjugate heat transfer in a curved pipe with a finite wall thickness can be satisfactorily analyzed by the present numerical method, and that the neglect of wall thickness in the prediction of pipe wall temperature distributions can provide unacceptably distorted results for the cases of pipes with thick wall such as safety related-piping systems of nuclear power plant.

A PARAMETRIC SCHEME FOR THE NUMERICAL SOLUTION OF THE BOUSSINESQ EQUATION

  • Bratsos, A.G.
    • Journal of applied mathematics & informatics
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    • 제8권1호
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    • pp.45-57
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    • 2001
  • A parametric scheme is proposed for the numerical solution of the nonlinear Boussinesq equation. The numerical method is developed by approximating the time and the space partical derivatives by finite-difference re placements and the nonlinear term by an appropriate linearized scheme. The resulting finite-difference method is analyzed for local truncation error and stability. The results of a number of numerical experiments are given for both the single and the double-soliton wave. AMS Mathematics Subject Classification : 65J15, 47H17, 49D15.

COMPACTLY SUPPORTED WAVELET AND THE NUMERICAL SOLUTION OF THE VLASOV EQUATION

  • Benhadid, Yacine
    • Journal of applied mathematics & informatics
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    • 제24권1_2호
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    • pp.17-30
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    • 2007
  • A new scheme for solving the Vlasov equation using a compactly supported wavelets basis is proposed. We use a numerical method which minimizes the numerical diffusion and conserves a reasonable time computing cost. So we introduce a representation in a compactly supported wavelet of the derivative operator. This method makes easy and simple the computation of the coefficients of the matrix representing the operator. This allows us to solve the two equations which result from the splitting technique of the main Vlasov equation. Some numerical results are exposed using different numbers of wavelets.

오차수정법을 도입한 비압축성 유체유동 해석을 위한 수치적 방법 (Numerical algorithm with the concept of defect correction for incompressible fluid flow analysis)

  • 권오붕
    • 대한기계학회논문집B
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    • 제21권3호
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    • pp.341-349
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    • 1997
  • The characteristics of defect correction method are discussed in a sample heat conduction problem showing the numerical solution of the error correction equation can predict the error of the numerical solution of the original governing equation. A way of using defect correction method combined with the existing algorithm for the incompressible fluid flow, is proposed and subsequently tested for the driven square cavity problem. The error correction equations for the continuity equation and the momentum equations are considered to estimate the errors of the numerical solutions of the original governing equations. With this new approach, better velocity and pressure fields can be obtained by correcting the original numerical solutions using the estimated errors. These calculated errors also can be used to estimate the orders of magnitude of the errors of the original numerical solutions.

수정 Berggren 법과 수치해석법에 의한 동결깊이 산정 비교 (Comparison of Modified Berggren Method with Numerical Method for the Frost Penetration Depth)

  • 김광진;김영진;이대영;이하영
    • 한국지반환경공학회 논문집
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    • 제14권6호
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    • pp.21-29
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    • 2013
  • 본 논문은 수정 Berggren 법과 상전이 현상을 모델링할 수 있는 유한요소 수치해석법을 사용하여 단열재를 포함한 대표적인 다층 지반에 대하여 동결깊이를 산정하여 비교 분석하였다. 균일한 단층 지반에서 수정 Berggren 법은 유한요소 수치해석법과 거의 동일한 결과를 보여주고 있다. 그러나 단열재를 포함한 다층 지반에서 수정 Berggren 법은 유한요소 수치해석 결과와 비교할 때 정확하지 않은 결과를 나타내고 있다. 따라서 단열재를 포함한 다층 지반에서는 수정 Berggren 법 대신에 유한요소나 유한차분법에 기반을 둔 수치해석법을 사용하여 동결깊이를 산정하여야 할 것으로 사료된다.

Computational Solution of a H-J-B equation arising from Stochastic Optimal Control Problem

  • Park, Wan-Sik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.440-444
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    • 1998
  • In this paper, we consider numerical solution of a H-J-B (Hamilton-Jacobi-Bellman) equation of elliptic type arising from the stochastic control problem. For the numerical solution of the equation, we take an approach involving contraction mapping and finite difference approximation. We choose the It(equation omitted) type stochastic differential equation as the dynamic system concerned. The numerical method of solution is validated computationally by using the constructed test case. Map of optimal controls is obtained through the numerical solution process of the equation. We also show how the method applies by taking a simple example of nonlinear spacecraft control.

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Numerical solution of singular integral equation for multiple curved branch-cracks

  • Chen, Y.Z.;Lin, X.Y.
    • Structural Engineering and Mechanics
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    • 제34권1호
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    • pp.85-95
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    • 2010
  • In this paper, numerical solution of the singular integral equation for the multiple curved branch-cracks is investigated. If some quadrature rule is used, one difficult point in the problem is to balance the number of unknowns and equations in the solution. This difficult point was overcome by taking the following steps: (a) to place a point dislocation at the intersecting point of branches, (b) to use the curve length method to covert the integral on the curve to an integral on the real axis, (c) to use the semi-open quadrature rule in the integration. After taking these steps, the number of the unknowns is equal to the number of the resulting algebraic equations. This is a particular advantage of the suggested method. In addition, accurate results for the stress intensity factors (SIFs) at crack tips have been found in a numerical example. Finally, several numerical examples are given to illustrate the efficiency of the method presented.

크랙에 의한 고온 초전도체 테이프의 임계전류 특성변화 (The variation of critical current by the formation of crack in a high-temperature superconducting tape)

  • 박을주;설승윤
    • 한국초전도ㆍ저온공학회논문지
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    • 제4권1호
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    • pp.73-77
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    • 2002
  • The variation of critical current by the formation of crack in a high temperature super-conducting tape was studied by experimental and numerical analyses. The current-voltage relation of HTS tape is measured by the four-point measurement method. Numerical analyses are used to solve two dimensional heat conduction equation, considering the temperature distribution. By comparing current-voltage relation of experimental and numerical results, the validity of numerical method is verified.

An Adaptive Mesh-Independent Numerical Integration for Meshless Local Petrov-Galerkin Method

  • Cho, Jin-Yeon;Jee, Young-Burm
    • Journal of Mechanical Science and Technology
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    • 제17권7호
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    • pp.986-998
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    • 2003
  • In this paper, an adaptive numerical integration scheme, which does not need non-overlapping and contiguous integration meshes, is proposed for the MLPG (Meshless Local Petrov-Galerkin) method. In the proposed algorithm, the integration points are located between the neighboring nodes to properly consider the irregular nodal distribution, and the nodal points are also included as integration points. For numerical integration without well-defined meshes, the Shepard shape function is adopted to approximate the integrand in the local symmetric weak form, by the values of the integrand at the integration points. This procedure makes it possible to integrate the local symmetric weak form without any integration meshes (non-overlapping and contiguous integration domains). The convergence tests are performed, to investigate the present scheme and several numerical examples are analyzed by using the proposed scheme.