A spectral characterization and an approximation scheme for the Hessian eigenvalue

tight frame approximation for multi-frames and super-frames

در این پایان نامه یک مولد برای چند قاب یا ابر قاب تولید شده تحت عمل نمایش یکانی تصویر برای گروه های شمارش پذیر گسسته بررسی خواهد شد. مثال هایی از این قاب ها چند قاب های گابور، ابرقاب های گابور و قاب هایی برای زیرفضاهای انتقال پایاست. نشان می دهیم که مولد چند قاب تنک نرمال شده (ابرقاب) یکتا وجود دارد به طوری که مینیمم فاصله را از ان دارد. همچنین مسایل مشابه برای قاب های دوگان مطرح شده و برخی ...

Eigenvalue Estimates And Singularities Of Hessian Fields

A parametric characterization and an ɛ-approximation scheme for the minimization of a quasiconcave program

This paper deals with the problem P of minimizing a quasiconcave function over a given feasible region. We first introduce an auxiliary problem P(A) with a parametric vector I such that, for an appropriate I, its optimal solution is also optimal to the original problem. Based on this, an approximation scheme for P is developed. If P(,l) is polynomially solvable, this becomes a polynomial time a...

Spectral approximation to a transmission eigenvalue problem and its applications to an inverse problem

We first develop an efficient spectral-Galerkin method and an rigorous error analysis for the generalized eigenvalue problems associated to a transmission eigenvalue problem. Then, we present an iterative scheme, based on computation of the first transmission eigenvalue, to estimate the index of refraction of an inhomogeneous medium. We present ample numerical results to demonstrate the effecti...

On an Approximation of the Hessian of the Lagrangian

In the context of SQP methods or, more recently, of sequential semidefinite programming methods, it is common practice to construct a positive semidefinite approximation of the Hessian of the Lagrangian. The Hessian of the augmented Lagrangian is a suitable approximation as it maintains local superlinear convergence under appropriate assumptions. In this note we give a simple example that the o...