Subspace iteration for computing several eigenpairs (i.e. eigenvalues and eigenvectors) of an eigenvalue problem is an alternative to the deflation technique whereby the eigenpairs are computed successively by projecting the problem onto the subspace orthogonal to the already found eigenvectors. The main advantage of the subspace iteration over the deflation is its ‘cluster robustness’: even if...

Previously a minimization principle for the sum of the first few smallest eigenvalues with the positive sign and Cauchy-like interlacing inequalities for the standard linear response eigenvalue problem for the 2n×2n matrix [ 0 K M 0 ] were obtained by the authors, where K and M are n×n real symmetric positive semi-definite matrices and one of them is definite. In this paper, a more general line...

although many methods exist for intensity modulated radiotherapy (imrt) fluence map optimization for crisp data, based on clinical practice, some of the involved parameters are fuzzy. in this paper, the best fluence maps for an imrt procedure were identifed as a solution of an optimization problem with a quadratic objective function, where the prescribed target dose vector was fuzzy. first, a d...

We consider variants of Davidson's method for the iterative computation of one or more eigenvalues and their corresponding eigenvectors of an n n matrix A. The original Davidson method 3], for real normal matrices A, may be viewed as an accelerated Gauss-Jacobi method, and the success of the method seems to depend quite heavily on diagonal dominance of A 3, 4, 17]. In the hope to enlarge the sc...

The rational eigenvalue problem is an emerging class of nonlinear eigenvalue problems arising from a variety of physical applications. In this paper, we propose a linearization-based method to solve the rational eigenvalue problem. The proposed method converts the rational eigenvalue problem into a well-studied linear eigenvalue problem, and meanwhile, exploits and preserves the structure and p...

Algorithms for performing blind channel identiication for a binary phase-shift keyed (BPSK) direct-sequence spread-spectrum (DS/SS) system operating over a fading channel are presented. These algorithms are derived by identifying the DS/SS system as a discrete oversampled system with intersymbol interference. In this setting the spreading code can be viewed as a transmit lter, the knowledge of ...

We present a minimization principle for the sum of the first few smallest positive eigenvalues and Cauchy-like interlacing inequalities for the linear response eigenvalue problem arising from the calculation of excitation states of many-particle systems, a hot topic among computational material scientists today for materials design to advance energy science. Subsequently, we develop the best ap...

the effect of boundary conditions on the solution of the inverse problem of identifying the geometry and location of a cavity inside an elastic solid body using displacement measurements obtained from a tension test is investigated. the boundary elements method (bem) coupled with the genetic algorithm (ga) and the conjugate gradient method (cgm) are implemented in this identification problem. a...