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71.
A. S. Usachev 《Siberian Mathematical Journal》2008,49(6):1136-1137
Under consideration is the space of almost convergent sequences as well as the operators acting on it. We prove that the space is invariant under the transformations of some class including, in particular, the Hardy and averaging operators. 相似文献
72.
Yu. A. Dabaghian 《Theoretical and Mathematical Physics》2008,156(1):996-1019
We discuss how to obtain exact and approximate distributions for various statistical characteristics of the spectra of quantum
graphs using previously found exact solutions of the spectral problem. We indicate the relation between the appearing spectral
decompositions and the theory of weakly dependent random variables and indicate the relation between the known limit theorems
for trigonometric sums and the universal statistical properties of the spectra of quantum chaotic systems.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 156, No. 1, pp. 38–66, July, 2008. 相似文献
73.
E. E. Permyakova 《Russian Mathematics (Iz VUZ)》2008,52(12):41-49
In this paper we prove a theorem on sufficient conditions for the convergence in the Skorokhod space D[0, 1] of a sequence of random processes with random time substitution. We obtain almost sure versions of this theorem. 相似文献
74.
B. G. Bhaskaran 《Queueing Systems》1986,1(1):103-127
Given conditions, which concern the infinitesimal parameters of two birth and death processes, the processes are constructed on the same probability space such that one process is almost surely larger than the other. Application is made to M/M/s queueing systems. Stochastic comparisons of queue length and virtual waiting time in two M/M/s systems are obtained. 相似文献
75.
A large set of CS(v, k, λ), k‐cycle system of order v with index λ, is a partition of all k‐cycles of Kv into CS(v, k, λ)s, denoted by LCS(v, k, λ). A (v ? 1)‐cycle is called almost Hamilton. The completion of the existence spectrum for LCS(v, v ? 1, λ) only depends on one case: all v ≥ 4 for λ = 2. In this article, it is shown that there exists an LCS(v, v ? 1,2) for any v ≡ 0,1 (mod 4) except v = 5, and for v = 6,7,10,11. © 2006 Wiley Periodicals, Inc. J Combin Designs 16: 53–69, 2008 相似文献
76.
This paper is to investigate the asymptotic dynamics in almost periodic cooperative systems with a first integral. By appealing to the theory of skew-product semiflows we establish the asymptotic almost periodicity of bounded solutions to such systems, which extends the existing convergence results for time independent and periodic cooperative systems with a first integral and proves a conjecture of B. Tang, Y. Kuang and H. Smith in SIAM J. Math. Anal., 24 (1993), 1331-1339.
77.
Z. Wang 《BIT Numerical Mathematics》2008,48(4):799-819
We present a method for solving a class of box constrained variational inequality problems. The method makes use of a procedure
for identifying some components of the solution by bounding it with an interval vector. It is shown that the method computes
an approximate solution of the variational inequality problem by solving at most n reduced systems of equations, where n is the dimension of the problem. Among those systems, only the one of the smallest dimension has to be solved with high accuracy.
The others are solved merely to identify some components of the solution, and so the computation can be done under a very
mild requirement of accuracy. Numerical results are presented for the obstacle problem, to illustrate the efficiency of the
method.
AMS subject classification (2000) 90C33, 65G30, 65K10 相似文献
78.
79.
Shenghan Zhou Houxiang Liu Bang Chen Wenkui Hou Xinpeng Ji Yue Zhang Wenbing Chang Yiyong Xiao 《Entropy (Basel, Switzerland)》2021,23(6)
The traditional sequential pattern mining method is carried out considering the whole time period and often ignores the sequential patterns that only occur in local time windows, as well as possible periodicity. Therefore, in order to overcome the limitations of traditional methods, this paper proposes status set sequential pattern mining with time windows (SSPMTW). In contrast to traditional methods, the item status is considered, and time windows, minimum confidence, minimum coverage, minimum factor set ratios and other constraints are added to mine more valuable rules in local time windows. The periodicity of these rules is also analyzed. According to the proposed method, this paper improves the Apriori algorithm, proposes the TW-Apriori algorithm, and explains the basic idea of the algorithm. Then, the feasibility, validity and efficiency of the proposed method and algorithm are verified by small-scale and large-scale examples. In a large-scale numerical example solution, the influence of various constraints on the mining results is analyzed. Finally, the solution results of SSPM and SSPMTW are compared and analyzed, and it is suggested that SSPMTW can excavate the laws existing in local time windows and analyze the periodicity of the laws, which solves the problem of SSPM ignoring the laws existing in local time windows and overcomes the limitations of traditional sequential pattern mining algorithms. In addition, the rules mined by SSPMTW reduce the entropy of the system. 相似文献
80.
REMARK ON STABILITY OF ISHIKAWA ITERATIVE PROCEDURES 总被引:2,自引:0,他引:2
1 IntroductionandPreliminariesSupposeEisarealBanachspaceandTisaselfmapofE .Supposex0 ∈Eandxn+1=f(T ,xn)definesaniterationprocedurewhichyieldsasequenceofpoints xn ∞n=0 inE .Foranexample ,thefunctioniterationxn+1=f(T ,xn) =Tx0 .SupposeF(T) =x∈E :Tx=x ≠ andthat xn convergess… 相似文献