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81.
本文讨论了动力系统的统计性质和动力性质的某些关系.对于紧致度量空间X上的连续自映射f,我们证明了:如果f满足大偏差定理,那么f是初值敏感的当且仅当f不是极小等度连续的. 相似文献
82.
本文考虑动力系统 (dx)/(dt)=f(x),x∈E~n,得出其周期轨道x(t)的最小周期T>0满足: TC≥2π,其中,而且2π是最好的常数。 相似文献
83.
N. Mazars 《商业与工业应用随机模型》1992,8(2):99-119
As shown in a companion-paper,1 binary and multinary coherent systems can be studied with unified arguments, through monotone binary coherent systems. These are binary coherent systems submitted to some monotone constraint and generalize the classic theory of free binary coherent systems. By considering the unified point of view thus obtained, this paper gives what is perhaps the most suggestive representation for multinary coherent systems, since this extends the definition of binary coherent systems in terms of series-parallel (parallel-series) structures. Then, this paper examines the special case of multinary systems that can be studied directly with the classic theory of free binary coherent systems. It thus enlarges and complements, in a shorter unified manner, the particular cases considered in earlier studies. 相似文献
84.
Ivo Nowak 《Annals of Global Analysis and Geometry》1993,11(4):331-344
Similar to the investigations of unstable polygonal minimal surfaces by Courant [1] we introduce here a variational principle for the free boundary problem with prescribed topological type which produces minimal surfaces in Riemannian manifolds with constant curvature. For special boundary configurations the surfaces have no branch points. The approach can be applied to numerical algorithms since it is constructive. 相似文献
85.
The solution of the Subproblem of the Cutting Angle Method of Global Optimization for problems of minimizing increasing positively homogeneous of degree one functions is proved to be NP-Complete. For the proof of this fact we formulate another problem which we call “Dominating Subset with Minimal Weight”. This problem is also NP-Complete. An O(n2)-time algorithm is presented for approximate solution of Dominant Subset with Minimal Weight Problem. This problem can be expressed as a kind of Assignment Problem in which it is allowed to assign multiple tasks to a single processor. Experimental analysis of the algorithm is performed using the program implemented in ANSI-C. The results of the analysis show the efficiency of the proposed algorithm.Mathematics Subject Classification (2000): 65K05, 90C27, 68Q25 相似文献
86.
Roger W. Barnard Clint Richardson Alexander Yu. Solynin 《Proceedings of the American Mathematical Society》2005,133(7):2091-2099
For the standard class of normalized univalent functions analytic in the unit disk , we consider a problem on the minimal area of the image concentrated in any given half-plane. This question is related to a well-known problem posed by A. W. Goodman in 1949 that regards minimizing area covered by analytic univalent functions under certain geometric constraints. An interesting aspect of this problem is the unexpected behavior of the candidates for extremal functions constructed via geometric considerations.
87.
We show that for a positive linear operator acting in ℓ2 and defined from
anxn+1+bnxn+an-1xn-1