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

In this paper we extend work of Kawamura, see kawamura, for Cuntz-Krieger algebras O_A for infinite matrices A. We generalize the definition of branching systems, prove their existence for any given matrix A and show how they induce some very concrete representations of O_A. 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 operator. We finish the paper with a few examples.Comment: 16 pages, 2 figure

Quantum photon correlations at the single atom level in free space

In this project, we present a novel approach to calculate and engineer the photon correlations emerging from the interference between an input field and the field scattered by an atom in free space. Historically, it has been difficult to observe robust quantum correlations in the total field, as the inefficient atom-light coupling in free space usually causes the scattered field to be small in comparison to the input. To overcome this issue, we propose the use of separate pump and probe beams, where the former effectively enhances the atomic emission to be comparable to the probe. Additionally, we elucidate the physical origin of the non-classical correlations predicted, by studying the transient atomic state after the measurement of a photon

Illuminating the charged leptons in the proton

The description of the structure of proton is fundamental in order to describe the standard model processes at the LHC as well as for the searching of New Physics. Quantum fluctuations imply the presence of photons and leptons inside the proton, which admit a parton distribution function (PDF). Although the lepton PDFs are expected to be small, its presence opens new production mechanisms. In order to explore the lepton - induced processes at the LHC, a precise determination of the leptonic content of the proton is needed. In this paper we propose to constrain the content of charged leptons inside the proton through the study of the QED Compton scattering in ultraperipheral proton - nucleus collisions at the LHC. We estimate the total cross sections and associated distributions considering different models for the lepton PDFs and distinct lepton flavours. We demonstrate that a future experimental analysis of this process is feasible and that it can be used to constrain the content of electrons, muons and taus inside the proton.Comment: 10 pages, 3 figures, 1 table. Improved version to be published in PR

The nZEBs in the near Future: Overview of definitions and guidelines towards existing plans for increasing nZEBs

Zero-energy performance buildings have gained significant attention since the publication in 2010 of the recast of the EPBD recast which requires all new buildings to become nearly zero-energy by 2020. Buildings are requested to meet higher levels of energy performance and to explore more the alternative energy supply systems available locally on a cost-efficiency basis. Since the directive does not specify minimum or maximum harmonized requirements as well as details of energy performance calculation framework, it is up to the member states to define the exact meaning of “high energy performance” and “amount of energy from renewable sources” according to their own local conditions and strategic interests. Nearly zero-energy building (nZEB) performance derives from net zero-energy concept (Net ZEB) which in case of buildings is usually defined as a high energy performance building that over a year is energy neutral. The successful implementation of such an ambitious target, however, needs to be planned out diligently. The critical steps are a) a correct picture about the existing state and trends, b) clear definitions and targets, c) dynamic building codes and energy efficient technologies and d) rules for testing and verification. The nZEBs or NetZEBs built in the near future therefore may play a critical role in implementing any ambitious plan as its success on long-term relies on setting best practice examples, in addition of the supporting policies and initiatives. The purpose of this paper is to review existing definitions, terms and policies on strategic planning of nZEBs at national and international level

Inclusão Social de Pessoas Cegas: treinamento no uso de leitor de tela

Anais do 35º Seminário de Extensão Universitária da Região Sul - Área temática: EducaçãoA ação de extensão apresentada neste trabalho teve por objetivo principal ofertar treinamento no uso do leitor de tela NVDA para pessoas cegas. Essa ação de extensão foi proposta para atender uma demanda apresentada pela comunidade. A metodologia envolveu ministrar um questionário inicial, definir o conteúdo programático do treinamento e a equipe executora, realizar um estudo dirigido como forma de preparação, fazer reuniões para discussão das técnicas de ensino e do material de apoio e preparar o laboratório. O treinamento promoveu uma introdução ao uso do computador para os participantes. O conhecimento adquirido, aliado a alguma prática regular, contribui para permitir a inclusão social e autonomia dos participantes. O treinamento ofereceu a oportunidade para a participação de seis alunos de graduação em atividades de extensão universitári

GESTION TEMPS REEL D’UN RESEAU D’ASSAINISSEMENT BASEE SUR LA SIMULATION D'UN MODELE CONTINU

Colloque avec actes et comité de lecture. internationale.International audience"Les outils actuels de gestion en temps réel des réseaux s’appuient sur deux outils logiciels : les logiciels de prévision météorologique et les logiciels de simulation hydraulique. L’usage des premiers est une cause importante d’imprécision et d’incertitude, l’usage des seconds oblige à des pas temporels de décision importants du fait de leur besoin en temps de calcul. Cette façon de procéder fait que les résultats obtenus sont généralement éloignés de ceux attendus.L’idée force du projet CARDIO est de changer de paradigme de base en abordant la problématique par la face « automatique » plutôt que par celle « hydrologie ». L’objectif est de rendre possible la réalisation d’un grand nombre de simulations en des temps très courts (quelques secondes) permettant de se passer des prévisions météorologiques en utilisant directement les données pluviométriques recueillies en temps réel. L’objectif est de parvenir à un système où la prise de décision est réalisée à partir de données fiables et où la correction de l’erreur est permanente.Les premiers résultats obtenus à partir d'une simulation d'un exemple test montrent l'efficacité de l’approche développée.