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81.
本文是一份综合报告,它基于作者的一部份研究工作和他在北京师范大学的五次讲演稿,以奇异分算子作为桥梁联结函数空间的结果和偏微分方程的结果作了阐述,它包括奇次空间上的调和分析,并应用到多复变函数论上,综述了右的结果并提出未解决的问题。 相似文献
82.
Rafael Espínola Adrian Petru?el 《Journal of Mathematical Analysis and Applications》2005,309(2):420-432
The purpose of this note is to present some fixed point and data dependence theorems in complete gauge spaces and in hyperconvex metric spaces for the so-called Meir-Keeler multivalued operators and admissible multivalued aα-contractions. Our results extend and generalize several theorems of Espínola and Kirk [R. Espínola, W.A. Kirk, Set-valued contractions and fixed points, Nonlinear Anal. 54 (2003) 485-494] and Rus, Petru?el, and Sînt?m?rian [I.A. Rus, A. Petru?el, A. Sînt?m?rian, Data dependence of the fixed point set of some multivalued weakly Picard operators, Nonlinear Anal. 52 (2003) 1947-1959]. 相似文献
83.
We directly use the quantum-invariant operator method to obtain the closed-form solution to the one-dimensional Dirac equation with a time-changing mass with a little manipulation. The solution got is also applicable forthe case with time-independence mass. 相似文献
84.
In this study, we identify a generalization of q-Bernstein type operators and investigate approximation properties of a sequence of these operators . We estimate rate of approximation by modulus of continuity. We prove Voronovskaya type theorem for these operators. 相似文献
85.
Luisa Beghin 《Stochastic Processes and their Applications》2018,128(7):2427-2447
We deal with some extensions of the space-fractional diffusion equation, which is satisfied by the density of a stable process (see Mainardi et al. (2001)): the first equation considered here is obtained by adding an exponential differential (or shift) operator expressed in terms of the Riesz–Feller derivative. We prove that this produces a random component in the time-argument of the corresponding stable process, which is represented by the so-called Poisson process with drift. Analogously, if we add, to the space-fractional diffusion equation, a logarithmic differential operator involving the Riesz-derivative, we obtain, as a solution, the transition semigroup of a stable process subordinated by an independent gamma subordinator with drift. Finally, we show that an extension of the space-fractional diffusion equation, containing both the fractional shift operator and the Feller integral, is satisfied by the transition density of the process obtained by time-changing the stable process with an independent linear birth process with drift. 相似文献
86.
The Pullback Asymptotic Behavior of the Solutions for 2D Nonautonomous G-Navier-Stokes Equations 下载免费PDF全文
Jinping Jiang Yanren Hou & Xiaoxia Wang 《advances in applied mathematics and mechanics.》2012,4(2):223-237
The pullback asymptotic behavior of the solutions for 2D Nonautonomous
G-Navier-Stokes equations is studied, and the existence of its $L^2$-pullback attractors on some bounded domains with Dirichlet boundary conditions
is investigated by using the measure of noncompactness. Then the estimation of
the fractal dimensions for the 2D G-Navier-Stokes equations is given. 相似文献
87.
We present a new derivation of the formula appearing in Babenko (1978) and Mayer and Roepstorff (1987) that gives the probability distribution of τ−n in terms of the eigenvalues of a symmetric operator. Here τ is the well-known Gauss-map. 相似文献
88.
We obtain global bounds in Lorentz–Morrey spaces for gradients of solutions to a class of quasilinear elliptic equations with low integrability data. The results are then applied to obtain sharp existence results in the framework of Morrey spaces for Riccati type equations with a gradient source term having growths below the natural exponent of the operator involved. A special feature of our results is that they hold under a very general assumption on the nonlinear structure, and under a mild natural restriction on the boundary of the ground domain. 相似文献
89.
Impact of Linear Operator on the Convergence of HAM Solution: A Modified Operator Approach 下载免费PDF全文
S. T. Hussain S. Nadeem & M. Qasim 《advances in applied mathematics and mechanics.》2016,8(3):499-516
The linear operator plays an important role in the computational process of
Homotopy Analysis Method (HAM). In HAM frame any kind of linear operator can
be chosen to develop a solution. Hence, it is easy to introduce the modified/physical
parameter dependent linear operators. The effective use of these operators has been
judged through solving fluid flow problems. Modification in linear operators affects
the solution and improves the computational efficiency of HAM for larger values of
parameters. The convergence rate of the solution is rapid and several times higher
resulting in less computational time. 相似文献
90.
Andrea Sacchetti 《Journal of statistical physics》2005,119(5-6):1347-1382
We consider time-dependent Schrödinger equations with a double well potential and an external nonlinear, both local and non-local, perturbation. In the semiclassical limit, the finite dimensional eigenspace associated to the lowest eigenvalues of the linear operator is almost invariant for times of the order of the beating period and the dominant term of the wavefunction is given by means of the solutions of a finite dimensional dynamical system. In the case of local nonlinear perturbation, we assume the spatial dimension d=1 or d=2. 相似文献