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Random perturbations of exponential Riesz bases in L 2 ( - π , π )

Gennadii Chistyakov, Yura Lyubarskii (1997)

Annales de l'institut Fourier

Let a sequence { λ n } be given such that the exponential system { exp ( i λ n x ) } forms a Riesz basis in L 2 ( - π , π ) and { ξ n } be a sequence of independent real-valued random variables. We study the properties of the system { exp ( i ( λ n + ξ n ) x ) } as well as related problems on estimation of entire functions with random zeroes and also problems on reconstruction of bandlimited signals with bandwidth 2 π via their samples at the random points { λ n + ξ n } .

Recobriments i grafs distància-regulars.

Josep Rifà Coma, Jaume Pujol Capdevila (1988)

Qüestiió

Uno de los aspectos claves en las telecomunicaciones está relacionado con el uso de los códigos correctores de errores para la transmisión de información. Actualmente se utiliza una clase muy simple de códigos; la implementación física de un código corrector de errores es complicada y costosa. En el campo de la Informática Teórica se intenta abordar el problema de los códigos correctores de errores desde diferentes ángulos. Uno de ellos es el de la Combinatoria Algebraica y, en particular, los grafos...

Recognition of atherosclerotic plaques and their extended dimensioning with computerized tomography angiography imaging

Tomasz Markiewicz, Mirosław Dziekiewicz, Marek Maruszyński, Romana Bogusławska-Walecka, Wojciech Kozłowski (2014)

International Journal of Applied Mathematics and Computer Science

In this paper the authors raise the issue of automatic discrimination of atherosclerotic plaques within an artery lumen based on numerical and statistical thresholding of Computerized Tomography Angiographic (CTA) images and their advanced dimensioning as a support for preoperative vessel assessment. For the study, a set of tomograms of the aorta, as well as the ilio-femoral and femoral arteries were examined. In each case a sequence of about 130-480 images of the artery cutoff planes were analyzed...

Reconstructibility of Boolean control networks with time delays in states

Ping Sun, Lijun Zhang, Kuize Zhang (2018)

Kybernetika

This paper deals with the reconstructibility of Boolean control networks (BCNs) with time delays in states. First, a survey on the semi-tensor product, weighted pair graph, constructed forest and finite automata is given. Second, by using the weighted pair graph, constructed forest and finite automata, an algorithm is designed to judge whether a Boolean control network with time delays in states is reconstructable or not under a mild assumption. Third, an algorithm is proposed to determine the current...

Recovery of band-limited functions on locally compact Abelian groups from irregular samples

H. G. Feichtinger, S. S. Pandey (2003)

Czechoslovak Mathematical Journal

Using the techniques of approximation and factorization of convolution operators we study the problem of irregular sampling of band-limited functions on a locally compact Abelian group G . The results of this paper relate to earlier work by Feichtinger and Gröchenig in a similar way as Kluvánek’s work published in 1969 relates to the classical Shannon Sampling Theorem. Generally speaking we claim that reconstruction is possible as long as there is sufficient high sampling density. Moreover, the iterative...

Recursively differentiable quasigroups and complete recursive codes

Vladimir I. Izbash, Paraskovya N. Syrbu (2004)

Commentationes Mathematicae Universitatis Carolinae

Criteria of recursive differentiability of quasigroups are given. Complete recursive codes which attains the Joshibound are constructed using recursively differentiable k -ary quasigroups.

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