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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
In this paper we consider operators of the form H=λ(-i∇), with λ analytic in a strip and with some specific growth conditions at infinity, and prove Hardy type estimates in L
2(ℝ
n
) with exponential weights. In fact we extend our previous results [19] from bounded analytic functions on a strip to analytic
functions with polynomial growth in that strip. 相似文献
992.
Instability of Solitary Waves in Nonlinear Composite Media 总被引:1,自引:0,他引:1
Ye Zhao 《应用数学学报(英文版)》2007,23(2):311-318
In this paper,we investigate a class of Hamiltonian systems arising in nonlinear composite media.By detailed analysis and computation we obtain a decaying estimates on the semigroup and prove the orbitalinstability of two families of explicit solitary wave solutions (slow family in anisotropic case and solitary wavesin isotropic case),which theoretically verify the related guess and numerical results. 相似文献
993.
Lanju Xu 《Discrete and Computational Geometry》2007,37(3):485-491
The lower bounds for the translative kissing numbers of superballs are studied in this note. We improve the bound given by
Larman and Zong. Furthermore, we give a constructive bound based on algebraic-geometry codes that also improves the bound
by Larman and Zong in almost all cases. 相似文献
994.
Labour scheduling plays an important and critical role in Sainsburys day to day operations and profitability. The integrated
workforce management solution for Sainsburys is an intelligent solution for the operational deployment of human resources,
integrated business forecasting, generation and calculation of workload and staff scheduling. The workforce management technology
has provided Sainsburys with a fully web-based and centralised system that produces optimised schedules for all employees
satisfying the forecasted demand of work with granularity of fifteen minutes. The system is configured to respect all operational
and business requirements as well as employee contractual constraints. This paper introduces the workforce management solution
system designed, developed and implemented for Sainsburys. We concentrate on two modelling structures, namely the work pattern
model and optimisation model, and briefly discuss the optimisation process. 相似文献
995.
This paper studies the tail behavior of the fundamental period in the MAP/G/1 queue. We prove that if the service time distribution
has a regularly varying tail, then the fundamental period distribution in the MAP/G/1 queue has also regularly varying tail,
and vice versa, by finding an explicit expression for the asymptotics of the tail of the fundamental period in terms of the
tail of the service time distribution. Our main result with the matrix analytic proof is a natural extension of the result
in (de Meyer and Teugels, J. Appl. Probab. 17: 802–813, 1980) on the M/G/1 queue where techniques rely heavily on analytic expressions of relevant functions.
I.-S. Wee’s research was supported by the Korea Research Foundation Grant KRF 2003-070-00008. 相似文献
996.
Cai-yun Jin Cao-zong Cheng Yong-tao Jin Jing Li 《应用数学学报(英文版)》2006,22(4):607-614
Two two-function minimax theorems are proved.The concavity-convexity conditions of the twofunctions involve strictly monotone transformations and mixing of the values of the two functions,and aredescribed by the inequalities as upward and weakly downward conditions. 相似文献
997.
998.
通过分析耦合参数作用、系统所呈现大尺度周期相态的复杂性以及与系统在无噪声条件下状态的比较,得出耦合振子系统的动力学行为比同类单振子系统的复杂,周期相态更稳定、抗噪能力更强.用构造的一类含特定恢复力项双中强度耦合Duffing振子系统检测色噪声背景中的谐波、方波信号,信噪比分别达到-111.0和-108.45dB.
关键词:
特定双耦合 Duffing振子系统
色噪声
周期信号
信噪比 相似文献
999.
Xin Tao YE Chong LI 《数学学报(英文版)》2007,23(1):65-76
The BCQ and the Abadie CQ for infinite systems of convex inequalities in Banach spaces are characterized in terms of the upper semi-continuity of the convex cones generated by the subdifferentials of active convex functions. Some relationships with other constraint qualifications such as the CPLV and the Slate condition are also studied. Applications in best approximation theory are provided. 相似文献
1000.
De Ming ZHU Ying SUN 《数学学报(英文版)》2007,23(8):1495-1504
In this paper, we study the dynamical behavior for a 4-dimensional reversible system near its heteroclinic loop connecting a saddle-focus and a saddle. The existence of infinitely many reversible 1-homoclinic orbits to the saddle and 2-homoclinic orbits to the saddle-focus is shown. And it is also proved that, corresponding to each 1-homoclinic (resp. 2-homoclinic) orbit F, there is a spiral segment such that the associated orbits starting from the segment are all reversible 1-periodic (resp. 2-periodic) and accumulate onto F. Moreover, each 2-homoclinic orbit may be also accumulated by a sequence of reversible 4-homoclinic orbits. 相似文献