This paper studies the use of a generalized hierarchical basis transformation at each level of a multilevel block factorization. The factorization may be used as a preconditioner to the conjugate gradient method, or the structure it sets up may be used to define a multigrid method. The basis transformation is performed with an averaged piecewise constant interpolant and is applicable to unstruc...

We present a practical approach for solving volume and surface mesh optimization problems. Our approach is based on Newton’s method which uses both first-order (gradient) and second-order (Hessian) derivatives of the nonlinear objective function. The volume and surface optimization algorithms are modified such that surface constraints and mesh validity are satisfied. We also propose a simple an...

The basic conjugate gradient method for unconstrained optimal control problems was proposed by Lasdon et al. in [1]. The penalty function approach to the solution of inequality constrained optimal control problems has been considered in [2] and the clipping-off technique that solves optimal control problems with magnitude constraint on the control inputs is described in [3, 4]. The proposed alg...

In this paper, we propose a new semi-supervised training method for Gaussian Mixture Models. We add a conditional entropy minimizer to the maximum mutual information criteria, which enables to incorporate unlabeled data in a discriminative training fashion. The training method is simple but surprisingly effective. The preconditioned conjugate gradient method provides a reasonable convergence ra...

The subject of the paper is the mesh independent convergence of the preconditioned conjugate gradient method for nonsymmetric elliptic problems. The approach of equivalent operators is involved, in which one uses the discretization of another suitable elliptic operator as preconditioning matrix. By introducing the notion of compact-equivalent operators, it is proved that for a wide class of ell...

Aggregation–based multigrid with standard piecewise constant like prolongation is investigated. Unknowns are aggregated either by pairs or by quadruplets; in the latter case the grouping may be either linewise or boxwise. A Fourier analysis is developed for a model two– dimensional anisotropic problem. Most of the results are stated for an arbitrary smoother (which fits with the Fourier analysi...

conclusions albumin gradient method is the enrichment of y-bearing chromosome sperms. separation of spermatozoa by albumin gradient method, introduced by ericsson, is a suitable method for sex selection of male offspring. this technique is safe, because it neither requires toxic materials during sperm separation, nor involves embryo manipulation. objectives the study aimed to assess the separat...