• 제목/요약/키워드: Equilibrium problems

검색결과 356건 처리시간 0.021초

다물체계의 평형위치에서 고유진동수에 대한 공차해석 (Tolerance Analysis for Natural Frequencies of Multi-body Systems in Dynamic Equilibrium State)

  • 엄승만;최동환;유홍희
    • 한국소음진동공학회논문집
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    • 제17권1호
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    • pp.65-71
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    • 2007
  • Tolerance analysis method for natural frequencies of multi-body systems having a equilibrium position is suggested in this paper. To perform the tolerance analysis, the Monte-Carlo Method is conventionally employed. However, the Monte-Carlo Method has some weakness; spending too much time for analysis and having a low accuracy and hard to converge in the dynamical unstable area. To resolve these problems, a tolerance analysis method is suggested in this paper. Sensitivity equations of natural frequencies are derived at the equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivity of natural frequencies can be calculated.

라듐 및 라돈의 감마선 분광 분석을 위한 알루미늄 용기의 제작 및 특성 조사 (A New Aluminium Container for $\gamma$-Ray Spectrometry Analysis of Radium and Radon)

  • 이길용;윤윤열;서범경
    • 분석과학
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    • 제13권6호
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    • pp.743-750
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    • 2000
  • 라듐 및 라돈과 같은 환경 방사성 핵종의 분석 방법 중 HPGe 검출기를 이용한 감마선 분광 분석법은 대부분 플라스틱 용기를 많이 이용하고 있다. 그러나 플라스틱 용기는 대기 중 라돈 딸 핵종의 흡착에 의해 백그라운드가 증가할 뿐만 아니라 방사 평형 과정에서 생성된 기체 상의 라돈의 손실에 의하여 완전한 방사 평형에 도달하지 않는다는 것이다. 이러한 문제점을 해결하기 위하여 알루미늄 재질의 측정 용기를 제작하였고, 그 특성을 조사하였다. 알루미늄 용기를 이용하여 방사 평형 과정을 조사한 결과, 고체 및 액체 시료 모두 기체 상태의 라돈 손실 없이 라듐과 그 딸핵종들이 측정 용기 안에서 완전한 방사 평형에 도달하는 것을 알았다. 또한 감마선 분광 분석법을 이용한 고체 및 액체 시료 중의 라듐 및 라돈의 비파괴 분석이 가능함을 확인하였다.

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탄소성 파괴해석을 위한 크랙 평면 평형모형과 항복 선형 파괴역학과의 비교에 관한 연구 (A Comparison of the Crack Plane Equilibrium Model for Elastic-Plastic Fracture Analysis with the Irwin's Plastic Zone Corrected LEFM)

  • 이규용
    • 수산해양기술연구
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    • 제20권1호
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    • pp.30-36
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    • 1984
  • 대규모의 소성역을 동반하면서 파괴하는 고인성 재료의 탄소성 파괴 반가를 위하여 제안된 바 있는 CPE 모형의 유효성을 입증하고자 소성역의 영향을 보정한 선형 파괴역학과의 이론적 검토와 오오스테나이트계 스테인레스강에 대한 실험적 비교검토를 통하여 얻은 결론은 다음과 같다. 예측한 바와 같이 선형 파괴역학의 적용은 소규모 항복조건이 성립하는 경우에만 가능하며 CPE 모형은 대변형을 형성하면서 파괴하는 경우의 파괴모형으로서 유효하다. 더욱 엄밀한 유효성을 입증하기 위하여 다음의 사항이 필요하다고 본다. 1. 크랙의 길이가 짧은 시험편에 대한 실험이 필요하다. 2. 크랙성장 개시점을 정확하게 찾을 수 있는 방법이 필요하다. 3. 파괴 진행영역에 대한 두께의 영향을 고려해 보아야 할 필요성이 있다.

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Algorithmic Properties of Isotone Complementarity Problems

  • Ahn, Byong-Hun
    • 한국경영과학회지
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    • 제12권1호
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    • pp.10-18
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    • 1987
  • This paper discusses algorithmic properties of a class of complementarity programs involving strictly diagonally isotone and off-diagonally isotone functions, i. e., functions whose Jacobian matrices have positive diagonal elements and nonnegative off-diagonal elements, A typical traffic equilibrium under elastic demands is cast into this class. Algorithmic properties of these complementarity problems, when a Jacobi-type iteration is applied, are investigated. It is shown that with a properly chosen starting point the generated sequence are decomposed into two converging monotonic subsequences. This and related will be useful in developing solution procedures for this class of complementarity problems.

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A GENERAL ITERATIVE ALGORITHM COMBINING VISCOSITY METHOD WITH PARALLEL METHOD FOR MIXED EQUILIBRIUM PROBLEMS FOR A FAMILY OF STRICT PSEUDO-CONTRACTIONS

  • Jitpeera, Thanyarat;Inchan, Issara;Kumam, Poom
    • Journal of applied mathematics & informatics
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    • 제29권3_4호
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    • pp.621-639
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    • 2011
  • The purpose of this paper is to introduce a general iterative process by viscosity approximation method with parallel method to ap-proximate a common element of the set of solutions of a mixed equilibrium problem and of the set of common fixed points of a finite family of $k_i$-strict pseudo-contractions in a Hilbert space. We obtain a strong convergence theorem of the proposed iterative method for a finite family of $k_i$-strict pseudo-contractions to the unique solution of variational inequality which is the optimality condition for a minimization problem under some mild conditions imposed on parameters. The results obtained in this paper improve and extend the corresponding results announced by Liu (2009), Plubtieng-Panpaeng (2007), Takahashi-Takahashi (2007), Peng et al. (2009) and some well-known results in the literature.

소비자교육의 정립을 위한 기초연구 (A Basic Study on the Establishment of the Consumer Education)

  • 김순미
    • 대한가정학회지
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    • 제20권4호
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    • pp.133-142
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    • 1982
  • The Consumer Education is one of the rapidly raised problems in the process of recent Economic Growth. As the Society and its economy changes into Oligopoly, the nature and the scope of the Consumer Education also changes. However, We don't have an institutional, systematic education of consumers. Even the basic concepts of Consumer Education has not yet been established, because it is in an infant state. Thus, the aim of this paper is to establish the fundermental concepts of Consumer Education and to help settlement of the direction of Consumer Education. The conclusions are as following: First, Consumers as the objects of Consumer Education are limited to the Ultimate-Consumer; and they can divided into three groups-Individual Consumer, Consumer-Group, the Consuming Masses. Now were have to deal with not only the concept of Ultimate Consumer which limited to the Consumer, but deal with the realistic problems involving Citizens and Livers. Second, Consumer Education is systematic educational activity in order that Consumers can assume an subjective behavior for the purpose of improvement and support of their own rights in society. Third, Consumer Education which enforced Consumers' Cooperative Society and Goods Test is the movements of systematic resistance of consumers. The former aims at Economic Equilibrium, while the latter Informative Equilibrium. so, the two movements should channel the direction of Consumer Education in order to realize the Equilibrium.

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Bilinear plate bending element for thin and moderately thick plates using Integrated Force Method

  • Dhananjaya, H.R.;Nagabhushanam, J.;Pandey, P.C.
    • Structural Engineering and Mechanics
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    • 제26권1호
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    • pp.43-68
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    • 2007
  • Using the Mindlin-Reissner plate theory, many quadrilateral plate bending elements have been developed so far to analyze thin and moderately thick plate problems via displacement based finite element method. Here new formulation has been made to analyze thin and moderately thick plate problems using force based finite element method called Integrated Force Method (IFM). The IFM is a novel matrix formulation developed in recent years for analyzing civil, mechanical and aerospace engineering structures. In this method all independent/internal forces are treated as unknown variables which are calculated by simultaneously imposing equations of equilibrium and compatibility conditions. In this paper the force based new bilinear quadrilateral plate bending element (MQP4) is proposed to analyze the thin and moderately thick plate bending problems using Integrated Force Method. The Mindlin-Reissner plate theory has been used in the formulation of this element which accounts the effect of shear deformation. Standard plate bending benchmark problems are analyzed using the proposed element MQP4 via Integrated Force Method to study its performance with respect to accuracy and convergence, and results are compared with those of displacement based 4-node quadrilateral plate bending finite elements available in the literature. The results are also compared with the exact solutions. The proposed element MQP4 is free from shear locking and works satisfactorily in both thin and moderately thick plate bending situations.

Some explicit solutions to plane equilibrium problem for no-tension bodies

  • Lucchesi, Massimiliano;Zani, Nicola
    • Structural Engineering and Mechanics
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    • 제16권3호
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    • pp.295-316
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    • 2003
  • A method is presented to integrate explicitly certain equilibrium problems for no-tension bodies, in absence of body forces and under the assumption that two of the principal stresses are everywhere null. The method is exemplified in the case of rectangular panels, clamped at their bottoms and loaded at their tops.

Solids 3-D with bounded tensile strength under the action of thermal strains. Theoretical aspects and numerical procedures

  • Pimpinelli, Giovanni
    • Structural Engineering and Mechanics
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    • 제18권1호
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    • pp.59-78
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    • 2004
  • This paper is devoted to illustrate some numerical procedures to solve the boundary equilibrium problems of three-dimensional solids that are subjected to thermal strains. The constitutive equations take into account the bounded tensile strength of the material and they are presented in the framework of non-linear elasticity and small strains. The associated equilibrium problem is solved numerically by means of the finite element method and the numerical techniques, i.e. the Newton-Raphson method and the secant method, are revised in order to assure the solution convergence of the discretized problem. Some numerical examples are illustrated.

NEW MAXIMUM THEOREMS WITH STRICT QUASI-CONCAVITY

  • Kim, Won-Kyu;Yoon, Ju-Han
    • 대한수학회보
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    • 제38권3호
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    • pp.565-573
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    • 2001
  • In this paper, we first rove the strict quasi-concavity of maximizing function, and next prove a new maximum theorem using Fan’s generalization of the classical KKM theorem. Also an existence theorem of social equilibrium can be proved when an additional assumption on the constraint correspondence is assumed. Finally, we give illustrative two examples of constrained optimization problems.

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