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101.
We generalise a necessary and sufficient condition given by Cohn for all the zeros of a self-inversive polynomial to be on the unit circle. Our theorem implies some sufficient conditions found by Lakatos, Losonczi and Schinzel. We apply our result to the study of a polynomial family closely related to Ramanujan polynomials, recently introduced by Gun, Murty and Rath, and studied by Murty, Smyth and Wang as well as by Lalín and Rogers. We prove that all polynomials in this family have their zeros on the unit circle, a result conjectured by Lalín and Rogers on computational evidence. 相似文献
102.
103.
In this paper we study and present a complete classification of spacelike surfaces with degenerate Gauss map in the Lorentz?CMinkowski space ${\mathbb L^4}$ . 相似文献
104.
Marianne Akian St��phane Gaubert Bas Lemmens 《Journal of Fixed Point Theory and Applications》2011,9(2):295-325
We study the stable behaviour of discrete dynamical systems where the map is convex and monotone with respect to the standard
positive cone. The notion of tangential stability for fixed points and periodic points is introduced, which is weaker than
Lyapunov stability. Among others we show that the set of tangentially stable fixed points is isomorphic to a convex inf-semilattice,
and a criterion is given for the existence of a unique tangentially stable fixed point. We also show that periods of tangentially
stable periodic points are orders of permutations on n letters, where n is the dimension of the underlying space, and a sufficient condition for global convergence to periodic orbits is presented. 相似文献
105.
In this paper a finite element formulation of a reduction method for dynamic buckling analysis of imperfection-sensitive shell structures is presented. The reduction method makes use of a perturbation approach, initially developed for static buckling and later extended to dynamic buckling analysis. The implementation of a single-mode dynamic buckling analysis in a general purpose finite element code is described. The effectiveness of the approach is illustrated by application to the dynamic buckling of composite cylindrical shells under axial and radial step loads. Results of the reduction method are compared with results available in the literature. The results are also compared with full model finite element explicit dynamic analysis, and a reasonable agreement is obtained. 相似文献
106.
We prove that a tolerance relation of a lattice is a homomorphic image of a congruence relation. 相似文献
107.
Ansgar J��ngel Stefan Krause Paola Pietra 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2011,62(4):623-639
Diffusive moment equations with an arbitrary number of moments are formally derived from the semiconductor Boltzmann equation employing a moment method and a Chapman?CEnskog expansion. The moment equations are closed by employing a generalized Fermi?CDirac distribution function obtained from entropy maximization. The current densities allow for a drift-diffusion-type formulation or a ??symmetrized?? formulation, using dual-entropy variables from nonequilibrium thermodynamics. Furthermore, drift-diffusion and new energy-transport equations based on Fermi?CDirac statistics are obtained and their degeneracy limit is studied. 相似文献
108.
We discuss problems and results on the maximum number of colors in combinatorial structures under the assumption that no totally multicolored sets of a specified type occur. 相似文献
109.
Arnoldo Bezanilla L��pez Omar Le��n S��nchez 《Advances in Applied Clifford Algebras》2011,21(4):757-772
In the last decade several versions of the Fourier transform have been formulated in the framework of Clifford algebra. We present a (Clifford-Fourier) transform, constructed using the geometric properties of Clifford algebra. We show the corresponding results of operational calculus, and a connection between the Fourier transform and this new transform. We obtain a technique to construct monogenic extensions of a certain type of continuous functions, and versions of the Paley-Wiener theorems are formulated. 相似文献
110.
������������淣������ 《应用概率统计》2016,32(5):452-462
??We consider probabilistic meanings for some numerical characteristics of single birth processes. Some probabilities of events, such as extinction probability, returning probability, are represented in terms of these numerical characteristics. Two examples are also presented to illustrate the value of the results. 相似文献