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991.
In this article, the complete convergence for sequences of asymptotically almost negatively associated (AANA) random variables is studied. As applications, the Baum–Katz-type theorem, Hsu–Robbins-type theorem and Marcinkiewicz–Zygmund strong law of large numbers for sequences of AANA random variables are obtained. 相似文献
992.
Eleftherios Lavdas Panayiotis Mavroidis Katerina Vassiou Violeta Roka Ioannis V. Fezoulidis Marianna Vlychou 《Magnetic resonance imaging》2010
The purpose of this study was to assess the effect of chemical shift artifacts and fat suppression between contrast-enhanced T1-weighted fast spin-echo (FSE) sequence with fat suppression and contrast-enhanced T1-weighted fluid attenuated inversion recovery (FLAIR) sequence with fat suppression in magnetic resonance imaging (MRI) of the thoracic spine at 3.0T. Forty patients, who underwent MRI examination, were recruited and analyzed both qualitatively and quantitatively. Due to chemical shift artifacts in the T1-weighted FSE, 14 of the patients were found to be of non-diagnostic value. On the contrary, in 11 of those 14 patients, no chemical shift artifacts were observed in the T1-weighted FLAIR sequence. Regarding the efficiency of fat suppression, both sequences achieved successful fat suppression. Consequently, the use of T1-weighted FLAIR fat suppression after contrast administration sequence seems to eliminate or significantly reduce image quality deterioration stemming from chemical shift artifacts in thoracic spine examinations. 相似文献
993.
Pavol Hell 《Discrete Mathematics》2009,309(18):5703-5373
A sequence 〈d1,d2,…,dn〉 of non-negative integers is graphical if it is the degree sequence of some graph, that is, there exists a graph G on n vertices whose ith vertex has degree di, for 1≤i≤n. The notion of a graphical sequence has a natural reformulation and generalization in terms of factors of complete graphs.If H=(V,E) is a graph and g and f are integer-valued functions on the vertex set V, then a (g,f)-factor of H is a subgraph G=(V,F) of H whose degree at each vertex v∈V lies in the interval [g(v),f(v)]. Thus, a (0,1)-factor is just a matching of H and a (1, 1)-factor is a perfect matching of H. If H is complete then a (g,f)-factor realizes a degree sequence that is consistent with the sequence of intervals 〈[g(v1),f(v1)],[g(v2),f(v2)],…,[g(vn),f(vn)]〉.Graphical sequences have been extensively studied and admit several elegant characterizations. We are interested in extending these characterizations to non-graphical sequences by introducing a natural measure of “near-graphical”. We do this in the context of minimally deficient (g,f)-factors of complete graphs. Our main result is a simple linear-time greedy algorithm for constructing minimally deficient (g,f)-factors in complete graphs that generalizes the method of Hakimi and Havel (for constructing (f,f)-factors in complete graphs, when possible). It has the added advantage of producing a certificate of minimum deficiency (through a generalization of the Erdös-Gallai characterization of (f,f)-factors in complete graphs) at no additional cost. 相似文献
994.
A note on the interlacing of zeros and orthogonality 总被引:1,自引:0,他引:1
Kathy Driver 《Journal of Approximation Theory》2009,161(2):508-510
Let be a sequence of monic polynomials with deg(tn)=n such that, for each n∈N, the zeros of tn are real and simple and tn and tn+1 have no common zeros. We discuss the connection between the orthogonality of the sequence, the positivity of a certain ratio, and the interlacing of the zeros of tn and tn+1 for n≥1, n∈N. 相似文献
995.
We study degree sequences for simplicial posets and polyhedral complexes, generalizing the well-studied graphical degree sequences. Here we extend the more common generalization of vertex-to-facet degree sequences by considering arbitrary face-to-flag degree sequences. In particular, these may be viewed as natural refinements of the flag f-vector of the poset. We investigate properties and relations of these generalized degree sequences, proving linear relations between flag degree sequences in terms of the composition of rank jumps of the flag. As a corollary, we recover an f-vector inequality on simplicial posets first shown by Stanley. 相似文献
996.
The paper is concerned with the higher order nonlinear neutral delay differential equation
997.
O. Blažeková 《Mathematica Slovaca》2009,59(3):315-322
The aim of this paper is to find main terms of the star D
N
* and extremal D
N
discrepancies of the two dimensional sequence (x
n
, x
n+1), n = 0, 1, 2, ..., N − 1, where x
n
, n = 0, 1, 2, ..., is the van der Corput sequence. This give a quantitative form of a well-known result that van der Corput
sequence is not pseudorandom.
This research was supported by the Slovak Academy of Sciences Vega Grant No. 2/7138/27. 相似文献
998.
In this paper we extend and improve some results of the large deviation for random sums of random variables. Let {Xn;n 〉 1} be a sequence of non-negative, independent and identically distributed random variables with common heavy-tailed distribution function F and finite mean μ ∈R^+, {N(n); n ≥0} be a sequence of negative binomial distributed random variables with a parameter p C (0, 1), n ≥ 0, let {M(n); n ≥ 0} be a Poisson process with intensity λ 〉 0. Suppose {N(n); n ≥ 0}, {Xn; n≥1} and {M(n); n ≥ 0} are mutually independent. Write S(n) =N(n)∑i=1 Xi-cM(n).Under the assumption F ∈ C, we prove some large deviation results. These results can be applied to certain problems in insurance and finance. 相似文献
999.
Takeshi Isobe 《Annals of Global Analysis and Geometry》2009,35(3):277-337
We study the interrelationship between topological and analytical properties of Sobolev bundles and describe some of their
applications to variational problems on principal bundles. We in particular show that the category of Sobolev principal G-bundles of class W
2,m/2 defined over M
m
is equivalent to the category of smooth principal G-bundles on M and give a characterization of the weak sequential closure of smooth principal G-bundles with prescribed isomorphism class. We also prove a topological compactness result for minimizing sequences of a conformally
invariant Yang-Mills functional.
相似文献
1000.
Yavuz Altin 《数学物理学报(B辑英文版)》2009,29(2):427-434
In this article, the author introduces the generalized difference paranormed sequence spaces c (△v^m, f, p, q, s), c0 (△v^m, f, p, q, s), and l∞ (△v^m, f, p, q, s) defined over a seminormed sequence space (X, q). The author also studies their properties like completeness, solidity, symmetricitv, etc. 相似文献