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991.
Shang Quan Bu 《数学学报(英文版)》2012,28(1):37-44
We study the well-posedness of the equations with fractional derivative Dαu(t)=Au(t)+f(t)(0 ≤t≤2π),where A is a closed operator in a Banach space X,0α1 and Dα is the fractional derivative in the sense of Weyl.Although this problem is not always well-posed in Lp(0,2π;X) or periodic continuous function spaces Cper([0,2π];X),we show by using the method of sum that it is well-posed in some subspaces of L p(0,2π;X) or C per([0,2π];X). 相似文献
992.
Yong Jiang Guo 《数学学报(英文版)》2012,28(2):379-404
A multi-class single server queue under non-preemptive static buffer priority (SBP) service discipline is considered in this
paper. Using a bounding technique, we obtain the fluid approximation for the queue length and busy time processes. Furthermore,
we prove that the convergence rate of the fluid approximation for the queue length and busy time processes is exponential
for large N. Additionally, a sufficient condition for stability is obtained. 相似文献
993.
MUB (mutually unbiased bases) 和SIC-POVM (symmetric informationally complete positiveoperator-valued measure) 是量子信息中的两个重要研究对象. 目前关于非素数幂维的完全MUB 是否存在还没有确定的结果, 对于SIC-POVM 目前只有有限多种维数K 有存在性结果或数值结果. 于是很多弱化了内积条件的近似MUB 和SIC-POVM 被人们所考虑. 本文使用Klappenecker 等人给出的近似MUB 和SIC-POVM 的定义, 利用Gauss 和与Jacobi 和对于素数方幂q给出了一类q-1 维q-近似MUB (AMUB)、一类q-1 维(q+1)AMUB 以及q+1 维qAMUB, 还利用Gauss 和给出了一类q-1 维近似SIC-POVM (ASIC-POVM). 相似文献
994.
995.
《复变函数与椭圆型方程》2012,57(11):897-908
Let H be the open upper half-plane, and H its closure. If ? is a non-constant transcendental entire function of exponential type such that |?(x)| ≥ μ > 0 on the real axis, then it may happen that |?(z)| is not greater than μ anywhere in H even if ?(z) in H. We show that if ? is an entire function of exponential type not vanishing in H such that inf x∈?|?(x)| = μ > 0, then inf z∈ H |?(z)| = μ if and only if h? (π/2) := lim sup y →∞y ? log|?(iy) ≥ 0, and that |?(z)| = mu for some z ∈ H only if ? is a constant. This result, which can be seen as a ‘minimum modulus principle’ for entire functions of exponential type not vanishing in a half-plane, helps us to obtain generalizations of two inequalities of Boas, and one of Turán. 相似文献
996.
In this paper,the expressions of tail value of risk(TVaR)and exponential tail value of risk(EVaR)for the total risk portfolio are given,which are splitted into two cases: the bivariate case and the multivariate case according to the number of the insurances.Then the risk contributions of the insurances portfolio and the credit portfolio are also obtained. Further more,for clarifying the above results,a numerical example is given. 相似文献
997.
998.
999.
In this paper we mainly study an equal mitosis two-phase cell division model. By using the C0-semigroup theory, we prove that this model is the well-posed in L1[0, 1] × L1[0, 1], and exhibits asynchronous exponential growth phenomenon as time goes to infinity. We also give a comparison between this two-phase model with the classical one-phase model. Finally, we briefly study the asymmetric two-phase cell division model, and show that similar results hold for it. 相似文献
1000.
Gorica Pavlovi? Svetlana Jankovi? 《Applied mathematics and computation》2012,218(10):6125-6134
The main objective of the paper is to present sufficient conditions ensuring the pth mean and almost sure exponential stability, as well as the pth mean integrability of solutions to non-linear stochastic functional differential equations and, especially, to stochastic differential equations with time-varying lags. Some examples are given to illustrate the theoretical considerations. 相似文献