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Graph C*-algebras, branching systems and the Perron-Frobenius operator [article]

Danilo Royer, Daniel Gonçalves
2014 arXiv   pre-print
We also show how to describe some Perron-Frobenius operators in L^1(X,μ), in terms of the representations we associate to a graph.  ...  explicitly describes the Perron-Frobenius operator P F for a large number of functions.  ...  In particular, each nonsingular map gives rise to a Perron-Frobenius operator on L 1 (X, µ).  ... 
arXiv:0908.1055v2 fatcat:yh6abee5rza47c22nfogtep3fu

Perron-Frobenius operators and representations of the Cuntz-Krieger algebras for infinite matrices [article]

Daniel Goncalves, Danilo Royer
2008 arXiv   pre-print
We use these representations to describe the Perron-Frobenius operator, associated to an nonsingular transformation, as an infinite sum and under some hypothesis we find a matrix representation for the  ...  The Perron-Frobenious Operator We now describe the Perron-Frobenious operator using the representations introduced in the previous section.  ...  Then the Perron-Frobenius operator restricted to W , P F | W : W → W , has a matrix representation given by A T B, where B is the diagonal infinite matrix with nonzero entries B i,i = b i .  ... 
arXiv:0808.0835v1 fatcat:nozh75lj5raztklf5okyo6nogm

Paths of matrices with the strong Perron-Frobenius property converging to a given matrix with the Perron-Frobenius property

Abed Elhashash, Uriel G. Rothblum, Daniel B. Szyld
2009 The Electronic Journal of Linear Algebra  
.; and Szyld, Daniel B.. (2009), "Paths of matrices with the strong Perron-Frobenius property converging to a given matrix with the Perron-Frobenius property", Abstract.  ...  It is known that a matrix A with the Perron-Frobenius property can always be the limit of a sequence of matrices A(ε) with the strong Perron-Frobenius property such that A − A(ε) ≤ ε.  ...  Rothblum, and Daniel B.  ... 
doi:10.13001/1081-3810.1349 fatcat:4yumob2lprh3nmltcq76eefa4m

The Perron method for p-harmonic functions in unbounded sets in R^n and metric spaces [article]

Daniel Hansevi
2016 arXiv   pre-print
., that their upper and lower Perron solutions coincide) and that the Perron solution coincides with the p-harmonic extension.  ...  The upper and lower (p-harmonic) Perron solutions are studied for p-parabolic open sets.  ...  The Perron method for solving the Dirichlet problem for harmonic functions (on R 2 ) was introduced in 1923 by Perron [29] (and independently by Remak [30] ).  ... 
arXiv:1504.06714v2 fatcat:2q46awagabasvoko4y2shobb4q

On general matrices having the Perron-Frobenius Property

Abed Elhashash, Daniel B. Szyld
2008 The Electronic Journal of Linear Algebra  
A matrix is said to have the Perron-Frobenius property if its spectral radius is an eigenvalue with a corresponding nonnegative eigenvector.  ...  Similarity transformations leaving such sets invariant are completely described, and it is shown that a nonnilpotent matrix eventually capturing the Perron-Frobenius property is in fact a matrix that already  ...  ELA 392 Abed Elhashash and Daniel B. Szyld the Perron-Frobenius property (section 4).  ... 
doi:10.13001/1081-3810.1271 fatcat:dranimce6bc5dhavv2tlrgoaca

Éditorial / Editorial

JEAN DANIEL JACOB, AMÉLIE PERRON, DAVE HOLMES
2015 Aporia  
Éditorial / Editorial
doi:10.18192/aporia.v7i1.3483 fatcat:7uo7e4adkfg7tcfk7lbcc5ruyi

A Clearer Picture of Blind Deconvolution [article]

Daniele Perrone, Paolo Favaro
2014 arXiv   pre-print
Blind deconvolution is the problem of recovering a sharp image and a blur kernel from a noisy blurry image. Recently, there has been a significant effort on understanding the basic mechanisms to solve blind deconvolution. While this effort resulted in the deployment of effective algorithms, the theoretical findings generated contrasting views on why these approaches worked. On the one hand, one could observe experimentally that alternating energy minimization algorithms converge to the desired
more » ... olution. On the other hand, it has been shown that such alternating minimization algorithms should fail to converge and one should instead use a so-called Variational Bayes approach. To clarify this conundrum, recent work showed that a good image and blur prior is instead what makes a blind deconvolution algorithm work. Unfortunately, this analysis did not apply to algorithms based on total variation regularization. In this manuscript, we provide both analysis and experiments to get a clearer picture of blind deconvolution. Our analysis reveals the very reason why an algorithm based on total variation works. We also introduce an implementation of this algorithm and show that, in spite of its extreme simplicity, it is very robust and achieves a performance comparable to the state of the art.
arXiv:1412.0251v1 fatcat:u4vgx4q44rgprnsjzztcwk5fhm

Two characterizations of matrices with the Perron-Frobenius property

Abed Elhashash, Daniel B. Szyld
2009 Numerical Linear Algebra with Applications  
If A ∈ R n×n has a basic and final class β for which A[β] has a left Perron-Frobenius eigenvector, then A T has the Perron-Frobenius property. Corollary 3.8.  ...  If A ∈ R n×n has two classes α and β, not necessarily distinct, such that: α is basic, initial, and A[α] has a right Perron-Frobenius eigenvector β is basic, final, and A[β] has a left Perron-Frobenius  ...  Often the right (or left) Perron-Frobenius eigenvector is called a Perron eigenvector, or simply a Perron vector.  ... 
doi:10.1002/nla.658 fatcat:xsmvmp2qdrc4ri4cjuolntefgq

Reply to F. Perrone et al

C. Daniel Mullins, Amy P. Abernethy, Arif Hussain, Russ W. Montgomery, Steven D. Pearson, Sean Tunis
2012 Journal of Clinical Oncology  
Daniel Mullins Center for Medical Technology Policy; and University of Maryland Baltimore, MD Amy P.  ...  Perrone et al We appreciate the favorable comments of Perrone et al' and their interest in our article.? We also appreciate the extent of their previous research in related areas.  ... 
doi:10.1200/jco.2012.43.3854 fatcat:a4zv7pprnzfy3lqqxeoytfhtey

Examples on Perron effects in autonomous discrete systems

Francisco Balibrea, M.V. Caballero, Witold Jarczyk, Daniele Fournier-Prunaret, João Manuel Gonçalves Cabral
2014 ESAIM Proceedings and Surveys  
Such examples complete some results from Demir and Koçak for one dimensional systems and prove the appearance of Perron effects in such systems.  ...  Ces examples complétent des résultats de Demir et Koçak pour systèmes de dimension un et démontrent l'apparition des effets de Perron dans les systèmes.  ...  In fact the contributions of this paper are examples in discrete dynamical systems of the well known Perron effect.  ... 
doi:10.1051/proc/201446001 fatcat:p5gh7kbqcracpccqbfom4pq2ya

Graph C⁎-algebras, branching systems and the Perron–Frobenius operator

Daniel Gonçalves, Danilo Royer
2012 Journal of Mathematical Analysis and Applications  
We also show how to describe the Perron-Frobenius operator of ergodic theory in terms of the representations we associate to a graph.  ...  In particular, each nonsingular map gives rise to a Perron-Frobenius operator on L 1 (X, μ).  ...  The next theorem shows a relation between this representation and the Perron-Frobenius operator P F . Theorem 4.4.  ... 
doi:10.1016/j.jmaa.2012.02.051 fatcat:fedhkvwkbzcpboinyv3yh2qm6a

Motion Deblurring for Plenoptic Images [article]

Paramanand Chandramouli, Paolo Favaro, Daniele Perrone
2016 arXiv   pre-print
Motion Deblurring for Plenoptic Images Paramanand Chandramouli, Paolo Favaro and Daniele Perrone Abstract-We address for the first time the issue of motion blur in light field images captured from plenoptic  ...  E-mail: chandra@iam.unibe.ch, paolo.favaro@iam.unibe.ch, perrone@iam.unibe.ch.  ... 
arXiv:1408.3686v2 fatcat:lm5hjn4eeza6tbn2psy4iorfby

Perron–Frobenius operators and representations of the Cuntz–Krieger algebras for infinite matrices

Daniel Gonçalves, Danilo Royer
2009 Journal of Mathematical Analysis and Applications  
Kawamura, The Perron-Frobenius operators, invariant measures and representations of the Cuntz-Krieger algebras, J. Math. Phys. 46 (2005) ], for Cuntz-Krieger algebras O A for infinite matrices A.  ...  We use these representations to describe the Perron-Frobenius operator, associated to a nonsingular transformation, as an infinite sum and under some hypothesis we find a matrix representation for the  ...  The Perron-Frobenius operator We now describe the Perron-Frobenius operator using the representations introduced in the previous section. Theorem 4.1.  ... 
doi:10.1016/j.jmaa.2008.11.018 fatcat:xx2giq7qvrgrrksowpluuxm3ky

The Perron method for $$\varvec{p}$$ p -harmonic functions in unbounded sets in $$\mathbf {R}^n$$ R n and metric spaces

Daniel Hansevi
2017 Mathematische Zeitschrift  
., that their upper and lower Perron solutions coincide), that the Perron solution agrees with the p-harmonic extension, and that Perron solutions are invariant under perturbation of the function on a  ...  The Perron method for solving the Dirichlet problem for harmonic functions (on R 2 ) was introduced in 1923 by Perron [29] (and independently by Remak [30]).  ...  In order to define Perron solutions, we need superharmonic functions.  ... 
doi:10.1007/s00209-017-1877-0 fatcat:fby6prs7pjaypbfrtxuzi4rsqm

L'ISOLAMENTO COME FORMA D'IMPEGNO NEL TEATRO CIVILE DI DANIELE TIMPANO

Lia PERRONE
2020 Studii si Cercetari Filolgice: Seria Limbi Romanice  
Nell'ambito di questa produzione, il "narrattore" Daniele Timpano si è fatto artefice di un'operazione unica nel suo genere: nella primavera 2013, quando ricorreva il trentacinquesimo anniversario della  ...  Dans le cadre de cette production, la démarche artistique de l'acteur-narrateur Daniele Timpano s'avère unique en son genre : au printemps 2013, lors du trente-cinquième anniversaire de la mort de Moro  ...  L'isolamento come strumento di denuncia Nel monologo di Daniele Timpano Aldo morto/Tragedia la vicenda dello statista democristiano è affrontata con animo dissacrante, come suggerisce d'emblée il titolo  ... 
doaj:adcc64ef8e914f07a78b797f7aedb0bd fatcat:rc5img75i5hi3new5enm5ijlxm
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