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191.
孟立平 《数学的实践与认识》2012,42(8):218-222
在不假定f满足非紧性测度条件及上下解存在的情形下,用算子谱理论与半序方法获得了有序Banach空间E中的非线性二阶周期边值问题■解的存在性结果. 相似文献
192.
文开庭 《应用泛函分析学报》2012,14(3):292-297
在GFC-空间中建立了新的KKM定理和Browder型不动点定理,作为应用,狭得了GFC-空间中的一般拟平衡问题系统和拟平衡问题系统的平衡存在定理. 相似文献
193.
Hui Liu 《数学学报(英文版)》2012,28(5):885-900
In this paper, let Σ R2n be a symmetric compact convex hypersurface which is ( r, R )- pinched with R/r (5/3)1/2 . Then Σ carries at least two elliptic symmetric closed characteristics; moreover, Σ carries at least E [ n-1/2 ] + E [ n-1/3 ] non-hyperbolic symmetric closed characteristics. 相似文献
194.
This paper discusses the problem of finite-time stability with respect to a closed, but not necessarily compact, invariant set for a class of nonlinear systems with discontinuous right-hand sides in the sense of the Filippov solutions. When the Lyapunov function is Lipschitz continuous and regular, the Lyapunov theorem on finite-time stability with respect to a closed invariant set is presented. 相似文献
195.
Details of the active ways to suppress Closed Orbit Distortion (COD), including bending magnet sorting and survey and alignment of the magnets, are discussed based on the studies of affections to the COD by the bending magnet field error and the misalignment of quadrupoles. The closed orbit correction and the Slow Orbit Feed Back (SOFB) system for the SSRF storage ring are presented in this paper. With these available methods, better results were obtained during the commissioning period with 3 GeV beam energy. 相似文献
196.
Charles Rezk 《Transactions of the American Mathematical Society》2001,353(3):973-1007
We describe a category, the objects of which may be viewed as models for homotopy theories. We show that for such models, ``functors between two homotopy theories form a homotopy theory', or more precisely that the category of such models has a well-behaved internal hom-object.
197.
A 2+1 version of a rotating perfect fluid spacetime of Gödel type is examined to see whether it has a Finkelstein-Misner kink. It is shown, by three different methods, that the kink number is one. 相似文献
198.
We study sequential convergences defined on a Boolean algebra by systems of maximal filters. We describe the order properties of the system of all such convergences. We introduce the category of 2-generated convergence Boolean algebras and generalize the construction of Novak sequential envelope to such algebras. 相似文献
199.
200.
This paper studies the queue-length process in a closed Jackson-type queueing network with the large number N of homogeneous customers by methods of the theory of martingales and by the up- and down-crossing method. The network considered
here consists of a central node (hub), being an infinite-server queueing system with exponentially distributed service times,
and k single-server satellite stations (nodes) with generally distributed service times with rates depending on the value N. The service mechanism of these k satellite stations is autonomous, i.e., every satellite server j serves the customers only at random instants that form a strictly stationary and ergodic sequence of random variables. Assuming
that the first k-1 satellite stations operate in light usage regime the paper considers the cases where the kth satellite station is a bottleneck node. The approach of the paper is based both on development of the method from the paper
by Kogan and Liptser [16], where a Markovian version of this model has been studied, and on development of the up- and down-crossing
method.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献