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101.
We provide normal forms and the global phase portraits in the Poincaré disk for all the Hamiltonian linear type centers of linear plus cubic homogeneous planar polynomial vector fields. 相似文献
102.
This work presents sufficient conditions for the existence of homoclinic solutions for second order coupled discontinuous systems of differential equations on the real line without the usual growth condition in the literature.The arguments apply the fixed point theory, Green's functions technique, -Carathéodory functions, lower and upper solutions and Schauder's fixed point theorem. 相似文献
103.
In this paper, we propose a sufficient and necessary condition for the boundedness of all the solutions for the equation with the critical situation that on g and p, where , is periodic and is bounded. 相似文献
104.
Sameerah Jamal 《Journal of Differential Equations》2019,266(7):4018-4026
A manifold that contains small perturbations will induce a perturbed partial differential equation. The partial differential equation that we select is the Poisson equation – in order to explore the interplay between the geometry of the manifold and the perturbations. Specifically, we show how the problem of symmetry determination, for higher-order perturbations, can be elegantly expressed via geometric conditions. 相似文献
105.
Alberto Cattaneo 《Mathematische Nachrichten》2019,292(10):2137-2152
We study automorphisms of the Hilbert scheme of n points on a generic projective K3 surface S, for any . We show that is either trivial or generated by a non‐symplectic involution and we determine numerical and divisorial conditions which allow us to distinguish between the two cases. As an application of these results we prove that, for any , there exist infinitely many admissible degrees for the polarization of the K3 surface S such that admits a non‐natural involution. This provides a generalization of the results of [7] for . 相似文献
106.
A.?N.?WilsonEmail author G.?D.?Dracoulis A.?P.?Byrne P.?M.?Davidson G.?J.?Lane R.?M.?Clark P.?Fallon A.?G?rgen A.?O.?Macchiavelli D.?Ward 《The European Physical Journal A - Hadrons and Nuclei》2005,24(2):179-183
A superdeformed band has been observed in the N = 108 isotope 190Pb. This is the most neutron-deficient Pb isotope in which superdeformed states have been observed. Several theoretical approaches have predicted that N = 108 will mark the limit of observable superdeformation in the Pb isotopes. The band, which consists of five (possibly six) transitions, is observed to feed at least one isomeric level in its decay to the ground state. This decay pattern supports a spin assignment of 10 for the lowest observed level. 相似文献
107.
A variety of theorems and properties of nonlinear DAEs were discussed in part I. This paper illustrates many of these ideas
within the context of analyzing a specific nonlinear system that exhibits a variety of interesting features.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
108.
Fatiha Alabau-Boussouira 《Journal of Evolution Equations》2006,6(1):95-112
This work is concerned with obtention of energy decay estimates for Petrowsky equation with a nonlinear dissipation which
is active only in an interior subset of the domain. We prove that the piecewise multiplier method as introduced by [20] and
[22] for the wave equation can be extended to the Petrowsky equation. Moreover, we also apply some recent results by the author
to obtain precise decay rate estimates for the energy, without specifying the growth of the nonlinear dissipation close to
the origin by means of convex properties and nonlinear integral inequalities for the energy of the solutions. 相似文献
109.
Precoloring extension on unit interval graphs 总被引:1,自引:0,他引:1
Dániel Marx 《Discrete Applied Mathematics》2006,154(6):995-1002
In the precoloring extension problem a graph is given with some of the vertices having preassigned colors and it has to be decided whether this coloring can be extended to a proper k-coloring of the graph. Answering an open question of Hujter and Tuza [Precoloring extension. III. Classes of perfect graphs, Combin. Probab. Comput. 5 (1) (1996) 35-56], we show that the precoloring extension problem is NP-complete on unit interval graphs. 相似文献
110.
In this paper, the boundedness of all solutions of the oscillator
is discussed, where ω is a positive constant, f(x,y),?(x) and p(t) are smooth functions, and p(t)=p(t+2π). 相似文献
x″+f(x,x′)+ω2x+?(x)=p(t)