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981.
Ciprian A. Tudor Nakahiro Yoshida 《Stochastic Processes and their Applications》2019,129(9):3499-3526
We develop the asymptotic expansion theory for vector-valued sequences of random variables in terms of the convergence of the Stein–Malliavin matrix associated with the sequence . Our approach combines the classical Fourier approach and the recent Stein–Malliavin theory. We find the second order term of the asymptotic expansion of the density of and we illustrate our results by several examples. 相似文献
982.
Sevda Yldz Fadime Dirik Kamil Demirci 《Mathematical Methods in the Applied Sciences》2019,42(16):5371-5382
In this paper, we study the Korovkin type approximation theorem for Ka‐ convergence, which is an interesting convergence method on weighted spaces. We also study the rate of Ka?convergence by using the weighted modulus of continuity and afterwards, we present a nontrivial application. 相似文献
983.
In this article, based on the variational approach, the existence of at least one nontrivial solution is studied for (p, q)‐Laplacian type impulsive fractional differential equations involving Riemann‐Liouville derivatives. Without the usual Ambrosetti‐Rabinowitz condition, the nonlinearity f in the paper is considered under some suitable assumptions. 相似文献
984.
Filipe J. Marques M. Theodor Loots Andriëtte Bekker 《Mathematical Methods in the Applied Sciences》2019,42(17):5718-5735
Series representations for several density functions are obtained as mixtures of generalized gamma distributions with discrete mass probability weights, by using the exponential expansion and the binomial theorem. Based on these results, approximations based on mixtures of generalized gamma distributions are proposed to approximate the distribution of the sum of independent random variables, which may not be identically distributed. The applicability of the proposed approximations are illustrated for the sum of independent Rayleigh random variables, the sum of independent gamma random variables, and the sum of independent Weibull random variables. Numerical studies are presented to assess the precision of these approximations. 相似文献
985.
986.
Ritu Agarwal Sunil D. Purohit Kritika 《Mathematical Methods in the Applied Sciences》2019,42(18):7160-7171
In calcium signalling, activation of receptor is a very significant aspect. To understand the mechanism of calcium signalling, receptors are the important components. The mobilization of intracellular calcium from intracellular stores depends upon binding of agonist to cell surface receptor. Thrombin is chosen as model ligand. In order to understand thrombin receptor activation, we analyze fractional model incorporating derivative of arbitrary order and nonsingular kernel which can precisely describe the effect of memory and can explain the model in better and more efficient manner as compared with fractional operators with singular kernels. The problem has been solved by perturbation iterative method. Using fixed‐point theorem, it is proved that solution of the system will exist and also it will be unique. 相似文献
987.
A milestone in probability theory is the law of the iterated logarithm (LIL), proved by Khinchin and independently by Kolmogorov in the 1920s, which asserts that for iid random variables with mean 0 and variance 1 In this paper we prove that LIL holds for various functionals of random graphs and hypergraphs models. We first prove LIL for the number of copies of a fixed subgraph H. Two harder results concern the number of global objects: perfect matchings and Hamiltonian cycles. The main new ingredient in these results is a large deviation bound, which may be of independent interest. For random k‐uniform hypergraphs, we obtain the Central Limit Theorem and LIL for the number of Hamilton cycles. 相似文献
988.
Explicit and partly sharp estimates are given of integrals over the square of Bessel functions with an integrable weight which can be singular at the origin. They are uniform with respect to the order of the Bessel functions and provide explicit bounds for some smoothing estimates as well as for the L2 restrictions of Fourier transforms onto spheres in which are independent of the radius of the sphere. For more special weights these restrictions are shown to be Hölder continuous with a Hölder constant having this independence as well. To illustrate the use of these results a uniform resolvent estimate of the free Dirac operator with mass in dimensions is derived. 相似文献
989.
In this paper, we study the existence of multiple positive solutions of Schrödinger–Poisson type equations with indefinite nonlinearity. Our main tool is the mountain pass theorem. 相似文献
990.
In the present paper, we give an answer to a question which is closely related to doubly warped product of Finsler metrics: ‘‘For each n, is there an n-dimensional Finsler manifold , admitting a non-constant smooth function f on M such that ?”. We relate the preceding mentioned condition to different concepts appeared and studied in Finsler geometry. We introduce and investigate the notion of a semi concurrent vector field on a Finsler manifold. We show that some special Finsler manifolds admitting such vector fields turn out to be Riemannian. We prove that Tachibana's characterization of Finsler manifolds admitting a concurrent vector field leads to Riemannian metrics. Various examples for conic Finsler spaces that admit semi-concurrent vector field are presented. 相似文献