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Dämpfung von Stosswellen im Experiment: drei Methoden im Vergleich
(1994)Arbeitsheft / Versuchsanstalt für Wasserbau, Hydrologie und Glaziologie der Eidgenössischen Technischen Hochschule ZürichReport -
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Micro-foundation for International Product Comparisons
(1994)Research Memorandum - Groningen Growth and Development CentreThis paper describes the methodology and procedures of international comparisons of productivity levels for twelve manufacturing industries (producing food products, beer, soap and detergents, iron and steel, machine tools, various types of machinery, computers, audio and video equipment, industrial electronics, wired communication equipment, passenger cars and car components) between Germany, Japan and the United States. These estimates ...Report -
Restarted GMRES preconditioned by deflation
(1994)SAM Research ReportThis paper presents a new preconditioning technique for solving linear systems. It is based on an invariant subspace approximation for the restarted GMRES algorithm. It uses the flexible GMRES scheme by designing a new preconditioning after each restart. Numerical examples show that this approach may converge almost as fast as full-GMRES at a, possibly, much lower cost.Report -
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Circuits in Power Electronics
(1994)SAM Research ReportThe dynamics of circuits in power electronics may often be modelled by means of systems of linear differential equations with piecewise constant coefficients and sinusoidal inhomogeneities. The Static Var (Volt-Ampere reactive) Compensator (SVC, a device for power network control) is a representative example. Initial value problems of this type may be handled by means of the matrix exponential, whereas the construction of periodic solutions ...Report -
The implementation of a Generalized Cross Validation algorithm using deflation techniques for linear systems
(1994)SAM Research ReportThe fitting of a thin plate smoothing spline to noisy data using the method of minimizing the Generalized Cross Validation (GCV) function is computationally intensive involving the repeated solution of sets of linear systems of equations as part of a minimization routine. In the case of a data set of more than a few hundred points, implementation on a workstation can become unrealistic and it is then desirable to exploit high performance ...Report -
An alternative to Ewald sums
(1994)SAM Research ReportIn this paper identities are derived which allow to compute the Coulomb energy associated with emN/em charges in a central cell and all their periodic images. These identities are all consequences of one basic identity which is obtained in a simple and straightforward way. It is possible to extend the results to other types of potentials as well.Report -
A deflation technique for linear systems of equations
(1994)SAM Research ReportIterative methods for solving linear systems of equations can be very efficient in a sequential or parallel computing environment if the structure of the coefficient matrix can be exploited to accelerate the convergence of the iterative process. However, for classes of problems for which suitable preconditioners cannot be found or for which the iteration scheme does not converge, iterative techniques are inappropriate. This paper proposes ...Report