• Title/Summary/Keyword: Functions of matrices

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Crosstalk between integrin and receptor tyrosine kinase signaling in breast carcinoma progression

  • Soung, Young-Hwa;Clifford, John L.;Chung, Jun
    • BMB Reports
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    • v.43 no.5
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    • pp.311-318
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    • 2010
  • This review explored the mechanism of breast carcinoma progression by focusing on integrins and receptor tyrosine kinases (or growth factor receptors). While the primary role of integrins was previously thought to be solely as mediators of adhesive interactions between cells and extracellular matrices, it is now believed that integrins also regulate signaling pathways that control cancer cell growth, survival, and invasion. A large body of evidence suggests that the cooperation between integrin and receptor tyrosine kinase signaling regulates certain signaling functions that are important for cancer progression. Recent developments on the crosstalk between integrins and receptor tyrosine kinases, and its implication in mammary tumor progression, are discussed.

System Identification of the Three Story Building Structure with a Controller (제어기가 설치된 3층 건물의 시스템 식별)

  • 주석준
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.203-211
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    • 1999
  • Threr are several methods in protecting the building structures from dynamic loads such as an earthquake and a wind. Among them applying a control force to the building structure is one of the methods to decrease the vibration. The most important and difficult problem in the active control is to obtain the mathematical model of the building structure with a controller. the effective active controller can be designed from the exact model of the system In this paper the three story test building with an active mass driver is identified experimentally. the system matrices corresponding to the experimental building are found and verified with the experimentally-obtained transfer functions and responses efficiently.

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Computational Efficiency of 3-D Contact Analysis by Domain/Boundary Decomposition Formulation (영역/경계 분할 정식화에 의한 삼차원 접촉 해석의 효율성 검토)

  • Shin, Eui-Sup;Kim, Yong-Uhn;Ryu, Han-Yeol
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.471-474
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    • 2007
  • A domain/boundary decomposition technique is applied to carry out efficient finite element analyses of 3-D contact problems. Appropriate penalty functions are selected for connecting an interface and contact interfaces with neighboring subdomains that satisfy continuity constraints. As a consequence, all the effective stiffness matrices have positive definiteness, and computational efficiency can be improved to a considerable degree. If necessary, any complex-shaped 3-D domain can be divided into several simple-shaped subdomains without considering the conformity of meshes along the interface. With a set of numerical examples, the basic characteristics of computational efficiency are investigated carefully.

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The Interpretation Uncertain Bound for the Uncertain Linear Systems via Lyapunov Equations (Lyapunov 방정식을 이용한 불확실한 선형 시스템의 섭동 유계 해석)

  • Cho, Do-Hyoun;Lee, Sang-Chul;Choi, Jin-Taik;Lee, Sang-Hun;Lee, Jong-Yong
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.485-486
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    • 2007
  • In this paper, we use Lyapunov equations and functions to consider the linear systems with perturbed system matrices. And we consider that what choice of Lyapunov function V would allow the largest perturbation and still guarantee that V is negative definite. We find that this is determined by testing for the existence of solutions to a related quadratic equation with matrix coefficients and unknowns the so-called matrix Riccati equation.

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System Realization by Using Inverse Discrete Fourier Transformation for Structural Dynamic Models

  • Kim, Hyeung Y.;W. B. Hwang
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.289-294
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    • 1998
  • The distributed-parameter structures expressed with the partial differential equations are considered as the infinite-dimensional dynamic system. For implementation of a controller in multivariate systems, it is necessary to derive the state-space reduced order model. By the eigensystem realization algorithm, we can yield tile subspace system with the Markov parameters derived from the measured frequency response function by the inverse discrete Fourier transformation. We also review the necessary conditions for the convergence of the approximation system and the error bounds in terms of the singular values of Markov-parameter matrices. To determine the natural frequencies and modal damping ratios, the modal coordinate transformation is applied to the realization system. The vibration test for a smart structure is performed to provide the records of frequency response functions used in the subspace system realization.

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The Interpretation Stability Uncertain Bound for the Uncertain Linear Systems via Lyapunov Equations (Lyapunov 방정식을 이용한 불확실한 선형 시스템의 안정한 섭동 유계 해석)

  • Cho, Do-Hyeoun;Lee, Sang-Hun;Lee, Jong-Yong
    • 전자공학회논문지 IE
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    • v.44 no.4
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    • pp.26-29
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    • 2007
  • In this paper, we use Lyapunov equations and functions to consider the linear systems with perturbed system matrices. And we consider that what choice of Lyapunov function V would allow the largest perturbation and still guarantee that V is negative definite. We find that this is determined by testing for the existence of solutions to a related quadratic equation with matrix coefficients and unknowns the matrix Riccati equation.

Variable-Node Element for Adaptive Finite Element Analysis of Stokes Flow around Structure (구조물 주변의 Stokes 흐름에 대한 적응적 유한요소 해석을 위한 변절점 요소)

  • 최창근;유원진;정근영
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1996.10a
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    • pp.168-175
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    • 1996
  • This paper deals with the variable-node element for fluid flow and the adaptive h-version mesh refinement algorithm. The transient element has been formulated by the Galerkin approach in which the pressure term is replaced with the penalty function. The present element having variable mid-side node and is suitable for constructing a locally refined mesh avoiding the use of the highly distorted elements. A modified Gauss quadrature is needed to integrate the element matrices to solve the trouble associated with the discontinuity of derivatives of shape functions. Several numerical examples show that the proposed element can be effectively used in the h-version adapt ive mesh refinement

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INVITED PAPER MULTIVARIATE ANALYSIS FOR THE CASE WHEN THE DIMENSION IS LARGE COMPARED TO THE SAMPLE SIZE

  • Fujikoshi, Yasunori
    • Journal of the Korean Statistical Society
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    • v.33 no.1
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    • pp.1-24
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    • 2004
  • This paper is concerned with statistical methods for multivariate data when the number p of variables is large compared to the sample size n. Such data appear typically in analysis of DNA microarrays, curve data, financial data, etc. However, there is little statistical theory for high dimensional data. On the other hand, there are some asymptotic results under the assumption that both and p tend to $\infty$, in some ratio p/n ${\rightarrow}$c. The results suggest that the new asymptotic results are more useful and insightful than the classical large sample asymptotics. The main purpose of this paper is to review some asymptotic results for high dimensional statistics as well as classical statistics under a high dimensional asymptotic framework.

A Spectral-Galerkin Nodal Method for Salving the Two-Dimensional Multigroup Diffusion Equations

  • Hongwu Cheng;Cho, Nam-Zin
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.157-162
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    • 1996
  • A novel nodal method is developed for the two-dimensional multi-group diffusion equations based on the Spectral-Galerkin approach. In this study, the nodal diffusion equations with Robin boundary condition are reformulated in a weak (variational) form, which is then approximated spatially by choosing appropriate basis functions. For the nodal coupling relations between the neighbouring nodes, the continuity conditions of partial currents are utilized. The resulting discrete systems with sparse structured matrices are solved by the Preconditioned Conjugate Gradient Method (PCG) and sweeping technique. The method is validated on two test problems.

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NUMERICAL SOLUTION OF THE NONLINEAR KORTEWEG-DE VRIES EQUATION BY USING CHEBYSHEV WAVELET COLLOCATION METHOD

  • BAKIR, Yasemin
    • Honam Mathematical Journal
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    • v.43 no.3
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    • pp.373-383
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    • 2021
  • In this study, a numerical method deals with the Chebyshev wavelet collocation and Adomian decomposition methods are proposed for solving Korteweg-de Vries equation. Integration of the Chebyshev wavelets operational matrices is derived. This problem is reduced to a system of non-linear algebraic equations by using their operational matrix. Thus, it becomes easier to solve KdV problem. The error estimation for the Chebyshev wavelet collocation method and ADM is investigated. The proposed method's validity and accuracy are demonstrated by numerical results. When the exact and approximate solutions are compared, for non-linear or linear partial differential equations, the Chebyshev wavelet collocation method is shown to be acceptable, efficient and accurate.