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121.

Generalized Pólya frequency functions are introduced through inverse Mellin transformations of the reciprocals of real entire functions with all zeros in sectors A ? and ? A ? for 0 ≤ ?π/4, where A ? := {z ? C||arg z| ≤ ?}. It is shown that the constant π/4 is best possible in this context.  相似文献   
122.

We give some characterization theorems for the D w -Laguerre-Hahn linear functionals and we extend the concept of the class of the usual Laguerre-Hahn functionals to the D w -Laguerre-Hahn functionals, recovering the classic results when w tends to zero. Moreover, we show that some transformations carried out on the D w -Laguerre-Hahn linear functionals lead to new D w -Laguerre-Hahn linear functionals. Finally, we analyze the class of the resulting functionals and we give some applications relative to the first associated Charlier, Meixner, Krawtchouk and Hahn orthogonal polynomials.  相似文献   
123.

In this paper stability and attractivity in non-autonomous time-discrete dynamical systems is investigated with the aid of Lyapunov functions. The results are applied to the problem of stabilization of controlled systems by feedback controls. In the final section of the paper we give sufficient conditions for norm-bounded null-controllability of linear systems.  相似文献   
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125.
《Optimization》2012,61(4):333-347
Necessary and sufficient conditions are established for properly efficient solutions of a class of nonsmooth nonconvex variational problems with multiple fractional objective functions and nonlinear inequality constraints. Based on these proper efficiency criteria. two multiobjective dual problems are constructed and appropriate duality theorems are proved. These proper efficiency and duality results also contain as special cases similar rcsults fer constrained variational problems with multiplei fractional. and conventional objective functions, which are particular cases of the main variational problem considered in this paper  相似文献   
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127.
《Optimization》2012,61(1-2):57-62
An efficient branch-and-bound algorithm for minimizing the sum of a convex function and the product of two affine functions over a convex set is proposed. The branching takes place in an interval of R the bounding is a relaxation  相似文献   
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129.
《Optimization》2012,61(2):135-158
Parametric and nonparametric sufficient optimality conditions are established for a class of nonsmooth generalized fractional programming problems containing ρ-univex functions. Subsequently, these optimality criteria are utilized as a basis for construction of two parametric and four parameter–free duality models and proving appropriate duality theorems  相似文献   
130.

In this paper we will discuss the problem of generation of sequences of orthogonal polynomials with respect to measures supported on the unit circle from a given sequence of orthogonal polynomials using a perturbation of a cubic sieved process. The basic tools are the Szeg? forward recurrence relation as well as the fact of the coprimality of orthogonal polynomials on the unit circle and their corresponding reverse polynomials. We also give the connection between the associated orthogonality measures. Finally, some examples of this cubic decomposition are shown.  相似文献   
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