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991.
We examine an infinite system of ordinary differential equations that models the binary coagulation and multiple fragmentation of clusters. In contrast to previous investigations, our analysis does not involve finite-dimensional truncations of the system. Instead, we treat the problem as an infinite-dimensional differential equation, posed in an appropriate Banach space, and apply perturbation results from the theory of strongly continuous semigroups of operators. The existence and uniqueness of physically meaningful solutions are established for uniformly bounded coagulation rates but with no growth restrictions imposed on the fragmentation rates. 相似文献
992.
The matrix-valued Weyl-Titchmarsh functions M(λ) of vector-valued Sturm-Liouville operators on the unit interval with the Dirichlet boundary conditions are considered. The collection of the eigenvalues (i.e., poles of M(λ)) and the residues of M(λ) is called the spectral data of the operator. The complete characterization of spectral data (or, equivalently, N×N Weyl-Titchmarsh functions) corresponding to N×N self-adjoint square-integrable matrix-valued potentials is given, if all N eigenvalues of the averaged potential are distinct. 相似文献
993.
In this paper a new concept for a 3×3 block operator matrix is studied on a Banach space. It is shown that, under certain conditions, it defines a closable operator and its essential spectra are determined. Application to transport operators in L1-space is given. 相似文献
994.
Luca Fanelli 《Journal of Mathematical Analysis and Applications》2009,357(1):1-420
We prove some uniform in ? a priori estimates for solutions of the equation
995.
M.A. El-Gebeily K. Al Shammari 《Journal of Mathematical Analysis and Applications》2009,358(2):345-354
We establish some existence results for the nonlinear problem Au=f in a reflexive Banach space V, without and with upper and lower solutions. We then consider the application of the quasilinearization method to the above mentioned problem. Under fairly general assumptions on the nonlinear operator A and the Banach space V, we show that this problem has a solution that can be obtained as the strong limit of two quadratically convergent monotone sequences of solutions of certain related linear equations. 相似文献
996.
A category of lattice-valued fuzzy interior operator spaces is defined and studied. Axioms are given in order for this category to be isomorphic to the category whose objects consist of all the stratified, lattice-valued, pretopological convergence spaces. 相似文献
997.
R. Yu. Amenzadeh 《Mechanics of Composite Materials》2009,45(2):159-164
The use of the hereditary theory for shells heterogeneous across their thickness is considered. A variational method is formulated
for calculating thin anisotropic shells made of a material whose deformation behavior can be described by relations of the
linear theory of viscoelasticity. In order to transform the corresponding functional into a form suitable for shells, some
assumptions related to concepts of the theory of thin shells are introduced. In the capacity of Euler equations, physical
relations, nonlinear equilibrium equations, and nonlinear boundary conditions are derived. The state equations are deduced
for a multilayered shell.
Translated from Mekhanika Kompozitnykh Materialov, Vol. 45, No. 2, pp. 231–240, March–April, 2009. 相似文献
998.
Rafael de la Llave Enrico Valdinoci 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2009,26(4):1309-1344
We discuss an Aubry–Mather-type theory for solutions of non-linear, possibly degenerate, elliptic PDEs and other pseudo-differential operators.We show that for certain PDEs and ΨDEs with periodic coefficients and a variational structure it is possible to find quasi-periodic solutions for all frequencies. This results also hold under a generalized definition of periodicity that makes it possible to consider problems in covers of several manifolds, including manifolds with non-commutative fundamental groups.An abstract result will be provided, from which an Aubry–Mather-type theory for concrete models will be derived. 相似文献
999.
利用Stroemberg-Torchinsky分解,给出了Triebel空间Fp-q(R^n,X)上算子值傅里叶乘子的一个充分条件.在n〈min(p,q)情形下,这里给出的充分条件改进了之前已知的结果. 相似文献
1000.
In this paper, the existence, uniqueness and global attractivity of positive periodic solutions for nonlinear impulsive systems are studied. Firstly, existence conditions are established by the method of lower and upper solutions. Then uniqueness and global attractivity are obtained by developing the theories of monotone and concave operators. And lastly, the method and the results are applied to the impulsive n-species cooperative Lotka–Volterra system and a model of a single-species dispersal among n-patches. 相似文献