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81.
Gancho Tachev 《Journal of Computational Analysis and Applications》2001,3(4):361-381
A direct theorem for approximation by algebraic polynomials in two variables with different degrees in each variable in Lp-metric (1 p ) on rectangles is proved, and the dependence of the constants on various parameters is studied. 相似文献
82.
W. P. Orrick B. Nickel A. J. Guttmann J. H. H. Perk 《Journal of statistical physics》2001,102(3-4):795-841
We have made substantial advances in elucidating the properties of the susceptibility of the square lattice Ising model. We discuss its analyticity properties, certain closed form expressions for subsets of the coefficients, and give an algorithm of complexity O(N6) to determine its first N coefficients. As a result, we have generated and analyzed series with more than 300 terms in both the high- and low-temperature regime. We quantify the effect of irrelevant variables to the scaling-amplitude functions. In particular, we find and quantify the breakdown of simple scaling, in the absence of irrelevant scaling fields, arising first at order |T–Tc|9/4, though high-low temperature symmetry is still preserved. At terms of order |T–Tc|17/4 and beyond, this symmetry is no longer present. The short-distance terms are shown to have the form (T–Tc)p (log |T–Tc|)q with pq2. Conjectured exact expressions for some correlation functions and series coefficients in terms of elliptic theta functions also foreshadow future developments. 相似文献
83.
J. Sunklodas 《Lithuanian Mathematical Journal》2001,41(3):292-305
We derive lower bounds for Lp norms
, in the central limit theorem for independent and m–dependent random variables with finite fifth order absolute moments and for independent and m–dependent identically distributed random variables with fourth order moments. 相似文献
84.
Baha-Eldin Khaledi Subhash Kochar 《Annals of the Institute of Statistical Mathematics》2001,53(3):620-630
Consider a multivariate mixture model where the random variables X
1, ..., X
n
given (1, ...,
n
), are conditionally independent. Conditions are obtained under which different kinds of positive dependence hold among X
i
's. The results obtained are applied to a variety of problems including the concomitants of order statistics and of record values; and to frailty models. 相似文献
85.
Orthogonal expansions in product Jacobi polynomials with respect to the weight function Wα, β(x)=∏dj=1 (1−xj)αj (1+xj)βj on [−1, 1]d are studied. For αj, βj>−1 and αj+βj−1, the Cesàro (C, δ) means of the product Jacobi expansion converge in the norm of Lp(Wα, β, [−1, 1]d), 1p<∞, and C([−1, 1]d) if
Moreover, for αj, βj−1/2, the (C, δ) means define a positive linear operator if and only if δ∑di=1 (αi+βi)+3d−1. 相似文献
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86.
Entangled states whose Wigner functions are non-negative may be viewed as being accounted for by local hidden variables (LHV).
Recently, there were studies of Bell’s inequality violation (BIQV) for such states in conjunction with the well known theorem
of Bell that precludes BIQV for theories that have LHV underpinning. We extend these studies to teleportation which is also
based on entanglement. We investigate if, to what extent, and under what conditions may teleportation be accounted for via
LHV theory. Our study allows us to expose the role of various quantum requirements. These are, e.g., the uncertainty relation
among non-commuting operators, and the no-cloning theorem which forces the complete elimination of the teleported state at
its initial port. 相似文献
87.
The thermal effects of an interface crack between two dissimilar half-spaces is considered. The interface cracks are partially or fully insulated, and spaced in a periodic array. Using the complex variable technique, the temperature and fluxes are found in closed form, and the interactions between heat flows due to nearby cracks are determined. 相似文献
88.
《Journal of computational and graphical statistics》2013,22(2):281-294
By introducing auxiliary variables, the traditional Markov chain Monte Carlo method can be improved in certain cases by implementing a “slice sampler.” In the current literature, this sampling technique is used to sample from multivariate distributions with both single and multiple auxiliary variables. When the latter is employed, it generally updates one component at a time. In this article, we propose two variations of a new multivariate normal slice sampling method that uses multiple auxiliary variables to perform multivariate updating. These methods are flexible enough to allow for truncation to a rectangular region and/or exclusion of any n-dimensional hyper-quadrant. We present results of our methods and existing state-of-the-art slice samplers by comparing efficiency and accuracy. We find that we can generate approximately iid samples at a rate that is more efficient than other methods that update all dimensions at once. Supplemental materials are available online. 相似文献
89.
J. Sunklodas 《Acta Appl Math》2008,102(1):87-98
In the present paper, we consider L
1 bounds for asymptotic normality for the sequence of r.v.’s X
1,X
2,… (not necessarily stationary) satisfying the ψ-mixing condition. The L
1 bounds have been obtained in terms of Lyapunov fractions which, in a particular case, under finiteness of the third moments
of summands and the finiteness of ∑
r≥1
r
2
ψ(r), are of order O(n
−1/2), where the function ψ participates in the definition of the ψ-mixing condition.
相似文献
90.
The stability of traveling wave solutions of scalar viscous conservation laws is investigated by decomposing perturbations into three components: two far-field components and one near-field component. The linear operators associated to the far-field components are the constant coefficient operators determined by the asymptotic spatial limits of the original operator. Scaling variables can be applied to study the evolution of these components, allowing for the construction of invariant manifolds and the determination of their temporal decay rate. The large time evolution of the near-field component is shown to be governed by that of the far-field components, thus giving it the same temporal decay rate. We also give a discussion of the relationship between this geometric approach and previous results, which demonstrate that the decay rate of perturbations can be increased by requiring that initial data lie in appropriate algebraically weighted spaces. 相似文献