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991.
An extended hyperbola function method is proposed to construct exact solitary wave solutions to nonlinear wave equation based upon a coupled Riccati equation. It is shown that more new solitary wave solutions can be found by this new method, which include kink-shaped soliton solutions, bell-shaped soliton solutions and new solitary wave.The new method can be applied to other nonlinear equations in mathematical physics. 相似文献
992.
993.
Genkai Zhang 《Acta Appl Math》2002,73(1-2):79-94
We give a brief survey on the study of constructions of invariant differential operators on Riemannian symmetric spaces and of combinatorial and analytical properties of their eigenvalues, and pose some open questions. 相似文献
994.
In this paper we study the oscillations for a class of functional differential inequalities. By using these properties some forced oscillations to the boundary value problems of functional partial differential equations are established. 相似文献
995.
We investigate neutron star properties by constructing a chiral SU(3) spontaneous breaking Lagrangian and using relativistic mean-field approximation. The results show that π- condensate appears at some baryon densities,and hyperons ∑- and A exist in neutron star matter at high density. In this model, neutron star's maximum mass is1.12Ms with corresponding radius about 8 km. 相似文献
996.
We study local convergence of quasi-Newton methods for solving systems of nonlinear equations defined by B-differentiable functions. We extend the classical linear and superlinear convergence results for general quasi-Newton methods as well as for Broyden's method. We also show how Broyden's method may be applied to nonlinear complementarity problems and illustrate its computational performance on two small examples. 相似文献
997.
Summary Analytic results for electronic kinetic energy are first presented for a hydrogen atom in a spherical cage for two radii near
to the corresponding densities employed in the path-integral Monte Carlo study of isochoric molecular dissociation in dense
hydrogen by Magroet al. (Magro W. R., Ceperley D. M., Pierleoni C. andBernu B.,Phys. Rev. Lett.,76 (1996) 1240). The relevance of the ?cage? results to the behaviour of dense atomic hydrogen is pointed out. Attention is
then shifted to the molecular regime, and the variation with density of electronic kinetic energy for a H2 molecule in a rigid spheroidal cage is compared and contrasted with the Monte Carlo findings. The rigid-cage model mimics
this, as well as bond length contraction, under compression. 相似文献
998.
Asymptotic normality of the solutions of the initial-value problems for multidimensional Burgers' equation with weakly dependent possible non-Gaussian initial condition is proved. 相似文献
999.
In this paper the calculation of resonance frequencies and threshold gains of distributed feedback (DFB) lasers with strong modulations is discussed. The theory is based on the Floquet solutions of a complex Hill differential equation. The dispersion relation of the above solutions is shown to be of importance for the behaviour of the resonances of the DFB laser. 相似文献
1000.