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991.
Tingfu Feng Pengcheng Niu Jing Qiao 《Journal of Mathematical Analysis and Applications》2018,457(1):822-840
In this paper, based on the Caffarelli–Kohn–Nirenberg inequalities on the Euclidean space and the weighted Hölder inequality, we establish the logarithmic Caffarelli–Kohn–Nirenberg inequalities and parameter type logarithmic Caffarelli–Kohn–Nirenberg inequalities, and give applications for the weighted ultracontractivity of positive strong solutions to a kind of evolution equations. We also prove corresponding logarithmic Caffarelli–Kohn–Nirenberg inequalities and parameter type logarithmic Caffarelli–Kohn–Nirenberg inequalities on the Heisenberg group and related to generalized Baouendi–Grushin vector fields. Some applications are provided. 相似文献
992.
《Mathematische Nachrichten》2018,291(2-3):264-283
Let C be a smooth projective curve and G be a finite subgroup of whose action is mixed, i.e. there are elements in G exchanging the two isotrivial fibrations of . Let be the index two subgroup . If G0 acts freely, then is smooth and we call it semi‐isogenous mixed surface. In this paper we give an algorithm to determine semi‐isogenous mixed surfaces with given geometric genus, irregularity and self‐intersection of the canonical class. As an application we classify irregular semi‐isogenous mixed surfaces with and geometric genus equal to the irregularity; the regular case is subjected to some computational restrictions. In this way we construct new examples of surfaces of general type with . We provide an example of a minimal surface of general type with and . 相似文献
993.
《Mathematical Methods in the Applied Sciences》2018,41(4):1331-1343
Lie group classification for a diffusion‐type system that has applications in plasma physics is derived. The classification depends on the values of 5 parameters that appear in the system. Similarity reductions are presented. Certain initial value problems are reduced to problems with the governing equations being ordinary differential equations. Examples of potential symmetries are also presented. 相似文献
994.
《Mathematical Methods in the Applied Sciences》2018,41(10):3868-3884
We investigate in this paper a thermoelastic system where the oscillations are defined by the Timoshenko model and the heat conduction is given by Green and Naghdi theories. We introduce 2 new stability numbers κ1 , κ2, and we prove a general decay result, from which the exponential and polynomial decays are only special cases. 相似文献
995.
Luc Molinet Didier Pilod Stéphane Vento 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2018,35(7):1719-1756
We show that the Cauchy problem for a class of dispersive perturbations of Burgers' equations containing the low dispersion Benjamin–Ono equation is locally well-posed in when . As a consequence, we obtain global well-posedness in the energy space as soon as , i.e. . 相似文献
996.
This paper considers the martingale problem for a class of weakly coupled Lévy type operators. It is shown that under some mild conditions, the martingale problem is well-posed and uniquely determines a strong Markov process . The process , called a regime-switching jump diffusion with Lévy type jumps, is further shown to possess Feller and strong Feller properties under non-Lipschitz conditions via the coupling method. 相似文献
997.
998.
Bogdanov-Takens bifurcation in a delayed Michaelis-Menten type ratio-dependent predator-prey system with prey harvesting
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Yunxian Dai Ping Yang Zhiliang Luo Yiping Lin 《Journal of Applied Analysis & Computation》2019,9(4):1333-1346
In this paper, we study a delayed Michaelis-Menten Type ratio-dependent predator-prey model with prey harvesting. By considering the characteristic equation associated with the nonhyperbolic equilibrium, the critical value of the parameters for the Bogdanov-Takens bifurcation is obtained. The conditions for the characteristic equation having negative real parts are discussed. Using the normal form theory of Bogdanov-Takens bifurcation for retarded functional differential equations, the corresponding normal form restricted to the associated two-dimensional center manifold is calculated and the versal unfolding is considered. The parameter conditions for saddle-node bifurcation, Hopf bifurcation and homoclinic bifurcation are obtained. Numerical simulations are given to support the analytical results. 相似文献
999.
In this paper, we study lattices of preradicals which are not small classes (in which case we say that the corresponding rings are p-large), and specially we consider some infinite representation type algebras. We construct an injective assignment between lattices of preradicals, using a full functor between the corresponding categories of modules, that satisfies certain conditions. We show that the polynomial ring over any field is p-large, and we use this fact to provide examples and some classes of algebras (both tame and wild) which are p-large. 相似文献
1000.
Velázquez in 1994 used the degree theory to show that there is a perturbation of Simons’ cone, starting from which the mean curvature flow develops a type II singularity at the origin. He also showed that under a proper time-dependent rescaling of the solution around the origin, the rescaled flow converges in the C0 sense to a minimal hypersurface which is tangent to Simons’ cone at infinity. In this paper, we prove that the rescaled flow actually converges locally smoothly to the minimal hypersurface, which appears to be the singularity model of the type II singularity. In addition, we show that the mean curvature of the solution blows up near the origin at a rate which is smaller than that of the second fundamental form. 相似文献