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901.
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We consider a diffuse interface model for the flow of two viscous incompressible Newtonian fluids with different densities in a bounded domain in two and three space dimensions and prove existence of weak solutions for it. In contrast to earlier contributions, we study a model with a singular nonlocal free energy, which controls the Hα/2-norm of the volume fraction. We show existence of weak solutions for large times with the aid of an implicit time discretization. 相似文献
904.
905.
906.
Inma P. Cabrera Pablo Cordero Emilio Muñoz-Velasco Manuel Ojeda-Aciego Bernard De Baets 《Mathematical Methods in the Applied Sciences》2020,43(9):5673-5680
Fuzzy-directed graphs are often chosen as the data structure to model and implement solutions to several problems in the applied sciences. Galois connections have also shown to be useful both in theoretical and in practical problems. In this paper, the notion of relational Galois connection is extended to be applied between transitive fuzzy directed graphs. In this framework, the components of the connection are crisp relations satisfying certain reasonable properties given in terms of the so-called full powering. 相似文献
907.
908.
Ahmed I. Zayed 《Proceedings of the American Mathematical Society》1996,124(12):3767-3776
An analog of the Whittaker-Shannon-Kotel'nikov sampling theorem is derived for functions with values in a separable Hilbert space. The proof uses the concept of frames and frame operators in a Hilbert space. One of the consequences of this theorem is that it allows us to derive sampling theorems associated with boundary-value problems and some homogeneous integral equations, which in turn gives us a generalization of another sampling theorem by Kramer.
909.
A.G. Baskakov 《Journal of Mathematical Analysis and Applications》2005,308(2):420-439
In this paper the representation theory of locally compact Abelian groups is used to introduce linear operators with the two-point Bohr spectrum and to study their spectral properties. In particular, the structure of the inverse operators is considered and the applications to the theory of difference operators are discussed. 相似文献
910.
Manuel Portilheiro 《Journal of Differential Equations》2003,195(1):66-81
In the first part of this paper we define solutions for certain nonlinear equations defined by accretive operators, “dissipative solution”. This kind of solution is equivalent to the viscosity solutions for Hamilton-Jacobi equations and to the entropy solutions for conservation laws.In this paper we use dissipative solutions to obtain several relaxation limits for systems of semilinear transport equations and quasilinear conservation laws. These converge to diffusion second-order equations and in one case to a single conservation law. The relaxation limit is obtained using a version of the perturbed test function method to pass to the limit. This guarantees existence for the considered equations. 相似文献