• 제목/요약/키워드: s-matrix

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A CHARACTERIZATION OF MINIMAL SEMIPOSITIVITY OF SIGN PATTERN MATRICES

  • Park, S.W.;Seol, H.G.;Lee, S.G.
    • 대한수학회논문집
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    • 제13권3호
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    • pp.465-473
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    • 1998
  • A real m $\times$ n matrix A is semipositive (SP) if there is a vector x $\geq$ 0 such that Ax > 0, inequalities being entrywise. A is minimally semipositive (MSP) if A is semipositive and no column deleted submatrix of A is semipositive. We give a necessary and sufficient condition for the sign pattern matrix with n positive entries to be minimally semipositive.

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Some Results of Non-Central Wishart Distribution

  • Chul Kang;Jong Tae Park
    • Communications for Statistical Applications and Methods
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    • 제5권2호
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    • pp.531-538
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    • 1998
  • This paper first examines the skewness of Wishart distribution, using Tracy and Sultan(1993)'s results. Second, it investigates the variance-covariance matrix of random matrix $S_Y=YY'$ which has a non-central Wishart distribution. Third, it proposes the exact form of the third moment of the random matrix with non-central Wishart distribution.

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관류보일러 스팀 온도의 동역학 행렬 제어에 관한 연구 (A Study on Dynamic Matrix Control to Boiler Steam Temperature)

  • 김우헌;문운철
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.323-325
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    • 2009
  • In this paper, we present simulation results of Dynamic Matrix Control(DMC) to a boiler steam temperature. In order to control of steam temperature, we choose the input-output variables and generate the step response model by each input variable's step test. After that, the control structure executes on-line control with optimization using step response model. Proposed controller is applied to the APESS(Doosan company's boiler model simulator) and it is observed that the simulation results show satisfactory performance of proposed control.

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Slices Analysis Method of Petri nets in FMS Using the Transitive Matrix

  • Kim, Jung-Won;Lee, Jong-Kun;Song, Yu-Jin;Kim, Jong-Wook
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.132.3-132
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    • 2001
  • In this paper, we focus on the analysis of the scheduling problem in FMS after slicing off some sub-nets using the transitive matrix. This class of Time Petri nets is obtained by merging subnets based on the machine's operations. We can divide original system into some subnets based on machine's operations using Time Petri nets slice and analyze the feasibility time in each schedules. In this paper, we show the usefulness of transitive matrix to slice off some subnets from the original net, and explain on an example.

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EXTREMAL CASES OF SN-MATRICES

  • Kim, Si-Ju;Choi, Tae-Young
    • 호남수학학술지
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    • 제30권4호
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    • pp.659-670
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    • 2008
  • We denote by $\mathcal{Q}$(A) the set of all real matrices with the same sign pattern as a real matrix A. A matrix A is an SN-matrix provided there exists a set S of sign pattern such that the set of sign patterns of vectors in the -space of $\tilde{A}$ is S, for each ${\tilde{A}}{\in}\mathcal{Q}(A)$. Some properties of SN-matrices arc investigated.

A Green's-Matrix Approach to Chemisorption

  • Jang, Yun-Hee;Kim, Ho-Jing
    • Bulletin of the Korean Chemical Society
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    • 제14권2호
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    • pp.238-243
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    • 1993
  • A self-consistent-field Green's matrix method for the calculation of electronic properties of chemisorbed system is devised and applied to the methanol on copper(110) surface. The method is based on CNDO Hartree-Fock approximation. Contour integration in the complex energy plane is used for an efficient calculation of the charge-density bond-order matrix. The information on each fragment prior to chemisorption is efficiently used and a small number of iterations are needed to reach the self-consistency. The changes of density of states and other quantities of methanol due to chemisorption are consistent with reported experimental results.

Role of Interface on the Development of Microstructure in Carbon-Carbon Composites

  • Dhakate, S.R.;Mathur, R.B.;Dhami, T.L.;Chauhan, S.K.
    • Carbon letters
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    • 제3권4호
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    • pp.192-197
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    • 2002
  • Microstructure plays an important role in controlling the fracture behaviour of carbon-carbon composites and hence their mechanical properties. In the present study effort was made to understand how the different interfaces (fiber/matrix interactions) influence the development of microstructure of the matrix as well as that of carbon fibers as the heat treatment temperature of the carbon-carbon composites is raised. Three different grades of PAN based carbon fibres were selected to offer different surface characteristics. It is observed that in case of high-strength carbon fiber based carbon-carbon composites, not only the matrix microstructure is different but the texture of carbon fiber changes from isotropic to anisotropic after HTT to $2600^{\circ}C$. However, in case of intermediate and high modulus carbon fiber based carbon-carbon composites, the carbon fiber texture remains nearly isotropic at $2600^{\circ}C$ because of relatively weak fiber-matrix interactions.

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2인 조정게임의 베이지안 의사결정모형 (On the Bayesian Fecision Making Model of 2-Person Coordination Game)

  • 김정훈;정민용
    • 한국경영과학회지
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    • 제22권3호
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    • pp.113-143
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    • 1997
  • Most of the conflict problems between 2 persons can be represented as a bi-matrix game, because player's utilities, in general, are non-zero sum and change according to the progress of game. In the bi-matrix game the equilibrium point set which satisfies the Pareto optimality can be a good bargaining or coordination solution. Under the condition of incomplete information about the risk attitudes of the players, the bargaining or coordination solution depends on additional elements, namely, the players' methods of making inferences when they reach a node in the extensive form of the game that is off the equilibrium path. So the investigation about the players' inference type and its effects on the solution is essential. In addition to that, the effect of an individual's aversion to risk on various solutions in conflict problems, as expressed in his (her) utility function, must be considered. Those kinds of incomplete information make decision maker Bayesian, since it is often impossible to get correct information for building a decision making model. In Baysian point of view, this paper represents an analytic frame for guessing and learning opponent's attitude to risk for getting better reward. As an example for that analytic frame. 2 persons'bi-matrix game is considered. This example explains that a bi-matrix game can be transformed into a kind of matrix game through the players' implicitly cooperative attitude and the need of arbitration.

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