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81.
In this paper, we are concerned with the multiplicity of solutions for a fourth-order impulsive differential equation with Dirichlet boundary conditions and two control parameters. Using variational methods and a three critical points theorem, we give some new criteria to guarantee that the impulsive problem has at least three classical solutions. We also provide an example in order to illustrate the main abstract results of this paper. 相似文献
82.
In this Note, we study a class of Neumann parametric elliptic equations driven by a nonhomogeneous differential operator and with a reaction that exhibits competing terms (concave–convex nonlinearities). Using the Ambrosetti–Rabinowitz condition and related topological and variational arguments, we prove a bifurcation result for large values of the parameter. 相似文献
83.
Ioan Mărcuţ 《Acta Mathematica》2014,213(1):137-198
We prove a rigidity theorem in Poisson geometry around compact Poisson submanifolds, using the Nash–Moser fast convergence method. In the case of one-point submanifolds (fixed points), this implies a stronger version of Conn’s linearization theorem [2], also proving that Conn’s theorem is a manifestation of a rigidity phenomenon; similarly, in the case of arbitrary symplectic leaves, it gives a stronger version of the local normal form theorem [7]. We can also use the rigidity theorem to compute the Poisson moduli space of the sphere in the dual of a compact semisimple Lie algebra [17]. 相似文献
84.
We study the dynamics of the space debris in the 1:1 and 2:1 resonances, where geosynchronous and GPS satellites are located. By using Hamiltonian formalism, we consider a model including the geopotential contribution for which we compute the secular and resonant expansions of the Hamiltonian. Within such model we are able to detect the equilibria and to study the main features of the resonances in a very effective way. In particular, we analyze the regular and chaotic behavior of the 1:1 and 2:1 resonant regions by analytical methods and by computing the Fast Lyapunov Indicators, which provide a cartography of the resonances. This approach allows us to detect easily the location of the equilibria, the amplitudes of the libration islands and the main dynamical stability features of the resonances, thus providing an overview of the 1:1 and 2:1 resonant domains under the effect of Earth’s oblateness. The results are validated by a comparison with a model developed in Cartesian coordinates, including the geopotential, the gravitational attraction of Sun and Moon and the solar radiation pressure. 相似文献
85.
We use some interpolation operators and some Bernstein type operators for construction of surfaces which satisfy some given conditions. 相似文献
86.
Existence and non-existence results are established for quasilinear elliptic problems with nonlinear boundary conditions and lack of compactness. The proofs combine variational methods with the geometrical feature, due to the competition between the different growths of the nonlinearities. 相似文献
87.
Iustin Coanda 《Annali dell'Universita di Ferrara》1986,32(1):71-78
Summary One proves some properties of the spectrum of the duals of the stable rank 3 reflexive sheaves onP
3 withc
1=0 andc
3=c
2
2
-c
2 and one determines the Chern classes of these duals.
Riassunto Si prova alcune proprietà dello spettro degli duali degli fasci riflessivi stabili di rango 3 suP 3 conc 1=0 ec 3=c 2 2 -c 2 e si determina le classi di Chern di questi duali.相似文献
88.
The low excited states of the69As nucleus have been described in the framework of theSU(6) particle-quadrupole-phonon coupling model (PTQM). 相似文献
89.
Iustin Coandâ 《Mathematische Annalen》1991,291(1):147-152
90.
Aequationes mathematicae - The Hardy–Littlewood–Pólya inequality of majorization is extended for $$\mathbf {\omega }$$ – $$\textbf{m}$$ –star-convex functions to the... 相似文献