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Sereeter, B. (author)During the normal operation, control and planning of the power system, grid operators employ numerous tools including the Power Flow (PF) and the Optimal Power Flow (OPF) computations to keep the balance in the power system. The solution of the PF computation is used to assess whether the power system can function properly for the given...doctoral thesis 2020
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Linear power flow method improved with numerical analysis techniques applied to a very large networkSereeter, B. (author), van Westering, W.H.P. (author), Vuik, Cornelis (author), Witteveen, C. (author)In this paper, we propose a fast linear power flow method using a constant impedance load model to simulate both the entire Low Voltage (LV) and Medium Voltage (MV) networks in a single simulation. Accuracy and efficiency of this linear approach are validated by comparing it with the Newton power flow algorithm and a commercial network design...journal article 2019
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Astudillo Rengifo, R.A. (author)In several applications in science and engineering, different types of matrix problems emerge from the discretization of partial differential equations.<br/>This thesis is devoted to the development of new algorithms to solve this<br/>kind of problems. In particular, when the matrices involved are sparse and<br/>nonsymmetric. The new algorithms...doctoral thesis 2018
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Baumann, M.M. (author)Seismic FullWaveform Inversion is an imaging technique to better understand the earth's subsurface. Therefore, the reflection intensity of sound waves is measured in a field experiment and is matched with the results from a computer simulation in a leastsquares sense. From a computational pointofview, but also from an economic view point,...doctoral thesis 2018
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Astudillo Rengifo, R.A. (author), van Gijzen, M.B. (author)This paper discusses the solution of largescale linear matrix equations using the Induced Dimension reduction method (IDR(s)). IDR(s) was originally presented to solve system of linear equations, and is based on the IDR(s) theorem. We generalize the IDR(s) theorem to solve linear problems in any finitedimensional space. This generalization...journal article 2016
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Astudillo, R. (author), Van Gijzen, M.B. (author)This paper discusses the solution of largescale linear matrix equations using the Induced Dimension reduction method (IDR(s)). IDR(s) was originally presented to solve system of linear equations, and is based on the IDR(s) theorem. We generalize the IDR(s) theorem to solve linear problems in any finitedimensional space. This generalization...report 2015
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He, X. (author), Neytcheva, M. (author), Vuik, C. (author)This paper deals with fast and reliable numerical solution methods for the incompressible nonNewtonian NavierStokes equations. To handle the nonlinearity of the governing equations, the Picard and Newton methods are used to linearize these coupled partial differential equations. For space discretization we use the finite element method and...report 2013
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Diao, H. (author)This thesis attempts to explain the convergence behaviour of solving Helmholtz problem by investigating its spectral properties. Fourier analysis is employ to solve the eigenvalues of the matrices that are involved in the iterative methods. The numerical experiment is conducted to verify the conclusions by Fourier analysis and also to reveal...master thesis 2012
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Sonneveld, P. (author)An explanation is given of the convergence behavior of IDR(s) methods. The convergence mechanism of these algorithms has two components. The first consists of damping properties of certain factors in the residual polynomials, which becomes less important for large values of s. The second component depends on the behavior of Lanczos polynomials...journal article 2012
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 Van de Sande, G.E.M. (author) master thesis 2012
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Van Gijzen, M.B. (author), Sleijpen, G.L.G. (author), Zemke, J.P. (author)We give two important generalizations of the Induced Dimension Reduction (IDR) approach for the solution of linear systems. We derive a flexible and a multishift QuasiMinimal Residual IDR (QMRIDR) variant. Numerical examples are presented to show the effectiveness of these new IDR variants compared to existing ones and to other Krylov subspace...report 2011
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Sleijpen, G.L.G. (author), Van Gijzen, M.B. (author)IDR(s) [P. Sonneveld and M. B. van Gijzen, SIAM J. Sci. Comput., 31 (2008), pp. 1035–1062] and BiCGstab(?) [G. L. G. Sleijpen and D. R. Fokkema, Electron. Trans. Numer. Anal., 1 (1993), pp. 11–32] are two of the most efficient shortrecurrence iterative methods for solving large nonsymmetric linear systems of equations. Which of the two is best...journal article 2010
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Van Gijzen, M.B. (author), Sonneveld, P. (author)The IDR(s) method that is proposed in [18] is a very efficient limited memory method for solving large nonsymmetric systems of linear equations. IDR(s) is based on the induced dimension reduction theorem, that provides a way to construct subsequent residuals that lie in a sequence of shrinking subspaces. The IDR(s) algorithm that is given in [18...report 2010
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Van Gijzen, M.B. (author), Collignon, T.P. (author)The IDR(s) method that is proposed in [26] is an efficient limited memory method for solving large nonsymmetric systems of linear equations. In [11] an IDR(s) variant is described that has a single synchronisation point per iteration step, which makes this variant wellsuited for parallel and grid computing. In this paper, we combine this IDR(s)...report 2010
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Sonneveld, P. (author)An explanation is given of the convergence behaviour of the IDR(s) methods. The convergence of the IDR(s) algorithms has two components. The first consists of damping properties of certain factors in the residual polynomials, which becomes less important for large values of s. The second component depends on the behaviour of quasiLanczos...report 2010
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Pollul, B. (author)We consider a NewtonKrylov approach for discretized compressible Euler equations. A good preconditioner in the Krylov subspace method is essential for obtaining an efficient solver in such an approach. In this paper we compare pointblockGaussSeidel, pointblockILU and pointblockSPAI preconditioners. It turns out that the SPAI method is...conference paper 2006
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Erlangga, Y.A. (author)In this report, several numerical aspects and diculties for solving a linear system derived from the timeharmonic wave equations are overviewed. The presentation begins with the derivation of the governing equation for waves propagating in general inhomogeneous media. Due to the need of numerical solutions, various discretizations based on...report 2002