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991.
992.
993.
Yongsheng Li 《Journal of Differential Equations》2006,223(2):261-289
In this paper, we consider the Cauchy problem of the long-wave-short-wave resonance equations. By making use of a Strichartz-type inequality for the solutions, decomposing suitably the solution semigroup into a decay parts and a more regular parts, and ruling out the “vanishing” and “dichotomy” of the solutions, we prove the existence of the global attractor and the asymptotic smoothing effect of the solutions. 相似文献
994.
Emre Alkan Andrew H. Ledoan Marian Vâjâitu Alexandru Zaharescu 《Monatshefte für Mathematik》2006,149(3):179-192
We provide bounds for the absolute discrepancy of sequences of fractions with denominators streaming in a given arithmetic
progression and satisfying divisibility constraints.
Supported by the CERES Program 4-147/2004 of the Romanian Ministry of Education and Research. 相似文献
995.
Jacob Mostovoy 《Topology》2006,45(2):281-293
It is shown that Segal's theorem on the spaces of rational maps from CP1 to CPn can be extended to the spaces of continuous rational maps from CPm to CPn for any m?n. The tools are the Stone-Weierstrass theorem and Vassiliev's machinery of simplicial resolutions. 相似文献
996.
This paper deals with the existence of travelling wave fronts in reaction-diffusion systems with spatio-temporal delays. Our approach is to use monotone iterations and a nonstandard ordering for the set of profiles of the corresponding wave system. New iterative techniques are established for a class of integral operators when the reaction term satisfies different monotonicity conditions. Following this, the existence of travelling wave fronts for reaction-diffusion systems with spatio-temporal delays is established. Finally, we apply the main results to a single-species diffusive model with spatio-temporal delay and obtain some existence criteria of travelling wave fronts by choosing different kernels. 相似文献
997.
The Weierstrass semigroup H(P) is well known and has been studied. Recently there has been a renewed interest in these semigroups because of applications in coding theory. Generalizations of the Weierstrass semigroup H(P) to n-tuples P1,…,Pn have been made and studied. We will state and study another possible generalization. 相似文献
998.
Romain Joly 《Journal of Differential Equations》2006,229(2):588-653
In this paper, we study the convergence of the wave equation with variable internal damping term γn(x)ut to the wave equation with boundary damping γ(x)⊗δx∈∂Ωut when (γn(x)) converges to γ(x)⊗δx∈∂Ω in the sense of distributions. When the domain Ω in which these equations are defined is an interval in R, we show that, under natural hypotheses, the compact global attractor of the wave equation damped on the interior converges in X=H1(Ω)×L2(Ω) to the one of the wave equation damped on the boundary, and that the dynamics on these attractors are equivalent. We also prove, in the higher-dimensional case, that the attractors are lower-semicontinuous in X and upper-semicontinuous in H1−ε(Ω)×H−ε(Ω). 相似文献
999.
1000.
Armengol Gasull 《Journal of Differential Equations》2005,213(2):255-288
The generic isolated bifurcations for one-parameter families of smooth planar vector fields {Xμ} which give rise to periodic orbits are: the Andronov-Hopf bifurcation, the bifurcation from a semi-stable periodic orbit, the saddle-node loop bifurcation and the saddle loop bifurcation. In this paper we obtain the dominant term of the asymptotic behaviour of the period of the limit cycles appearing in each of these bifurcations in terms of μ when we are near the bifurcation. The method used to study the first two bifurcations is also used to solve the same problem in another two situations: a generalization of the Andronov-Hopf bifurcation to vector fields starting with a special monodromic jet; and the Hopf bifurcation at infinity for families of polynomial vector fields. 相似文献