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951.
We prove that,as in the finite dimensional case,the space of Bloch functions on the unit ball of a Hilbert space contains,under very mild conditions,any semi-Ba... 相似文献
952.
Erdogdu Murat A. Ozdaglar Asuman Parrilo Pablo A. Vanli Nuri Denizcan 《Mathematical Programming》2022,195(1-2):243-281
Mathematical Programming - Semidefinite programming (SDP) with diagonal constraints arise in many optimization problems, such as Max-Cut, community detection and group synchronization. Although... 相似文献
953.
Given a finite family F\mathcal{F} of linear forms with integer coefficients, and a compact abelian group G, an F\mathcal{F}-free set in G is a measurable set which does not contain solutions to any equation L(x)=0 for L in F\mathcal{F}. We denote by dF(G)d_{\mathcal{F}}(G) the supremum of μ(A) over F\mathcal{F}-free sets A⊂G, where μ is the normalized Haar measure on G. Our main result is that, for any such collection F\mathcal{F} of forms in at least three variables, the sequence
dF(\mathbb Zp)d_{\mathcal{F}}({\mathbb {Z}}_{p}) converges to
dF(\mathbb R/\mathbb Z)d_{\mathcal{F}}({\mathbb {R}}/{\mathbb {Z}}) as p→∞ over primes. This answers an analogue for ℤ
p
of a question that Ruzsa raised about sets of integers. 相似文献
954.
We study the asymptotic zero distribution of type II multiple orthogonal polynomials associated with two Macdonald functions (modified Bessel functions of the second kind). On the basis of the four-term recurrence relation, it is shown that, after proper scaling, the sequence of normalized zero counting measures converges weakly to the first component of a vector of two measures which satisfies a vector equilibrium problem with two external fields. We also give the explicit formula for the equilibrium vector in terms of solutions of an algebraic equation. 相似文献
955.
R. Gutiérrez C. Roldán R. Gutiérrez-Sánchez J. M. Angulo 《Methodology and Computing in Applied Probability》2007,9(3):413-423
This paper describes techniques for estimation, prediction and conditional simulation of two-parameter lognormal diffusion
random fields which are diffusions on each coordinate and satisfy a particular Markov property. The estimates of the drift
and diffusion coefficients, which characterize the lognormal diffusion random field under certain conditions, are used for
obtaining kriging predictors. The conditional simulations are obtained using the estimates of the drift and diffusion coefficients,
kriging prediction and unconditional simulation for the lognormal diffusion random field.
相似文献
956.
If points in nontrivial Gleason parts of a uniform Banach algebra have unique representing measures, then the weak and the norm topology coincide on the spectrum. We derive from this several consequences about weakly compact homomorphisms and discuss the case of other uniform Banach algebras arising in complex infinite dimensional analysis. 相似文献
957.
The standard way to represent a choice between n alternatives in Mixed Integer Programming is through n binary variables that add up to one. Unfortunately, this approach commonly leads to unbalanced branch-and-bound trees and diminished solver performance. In this paper, we present an encoding formulation framework that encompasses and expands existing approaches to mitigate this behavior. Through this framework, we generalize the incremental formulation for piecewise linear functions to any finite union of polyhedra with identical recession cones. 相似文献
958.
Pablo A. Maya Duque Sofie Coene Peter Goos Kenneth Sörensen Frits Spieksma 《European Journal of Operational Research》2013
The accessibility arc upgrading problem (AAUP) is a network upgrading problem that arises in real-life decision processes such as rural network planning. In this paper, we propose a linear integer programming formulation and two solution approaches for this problem. The first approach is based on the knapsack problem and uses the knowledge gathered from an analytical study of some special cases of the AAUP. The second approach is a variable neighbourhood search with strategic oscillation. The excellent performance of both approaches is demonstrated using a large set of randomly generated instances. Finally, we stress the importance of a proper allocation of scarce resources in accessibility improvement. 相似文献
959.
Pablo Hernandez-Leal Jesus A. Gonzalez Eduardo F. Morales L. Enrique Sucar 《International Journal of Approximate Reasoning》2013,54(8):956-977
Temporal Nodes Bayesian Networks (TNBNs) are an alternative to Dynamic Bayesian Networks for temporal reasoning with much simpler and efficient models in some domains. TNBNs are composed of temporal nodes, temporal intervals, and probabilistic dependencies. However, methods for learning this type of models from data have not yet been developed. In this paper, we propose a learning algorithm to obtain the structure and temporal intervals for TNBNs from data. The method consists of three phases: (i) obtain an initial approximation of the intervals, (ii) obtain a structure using a standard algorithm and (iii) refine the intervals for each temporal node based on a clustering algorithm. We evaluated the method with synthetic data from three different TNBNs of different sizes. Our method obtains the best score using a combined measure of interval quality and prediction accuracy, and a competitive structural quality with lower running times, compared to other related algorithms. We also present a real world application of the algorithm with data obtained from a combined cycle power plant in order to diagnose temporal faults. 相似文献
960.