Joint Information and Jamming Beamforming for Secrecy Rate Maximization in Cognitive Radio Networks

In this paper, we consider the secure beamforming design for an underlay cognitive radio multiple-input singleoutput broadcast channel in the presence of multiple passive eavesdroppers. Our goal is to design a jamming noise (JN) transmit strategy to maximize the secrecy rate of the secondary system. By utilizing the zero-forcing method to eliminate the interference caused by JN to the secondary user, we study the joint optimization of the information and JN beamforming for secrecy rate maximization of the secondary system while satisfying all the interference power constraints at the primary users, as well as the per-antenna power constraint at the secondary transmitter. For an optimal beamforming design, the original problem is a nonconvex program, which can be reformulated as a convex program by applying the rank relaxation method. To this end, we prove that the rank relaxation is tight and propose a barrier interior-point method to solve the resulting saddle point problem based on a duality result. To find the global optimal solution, we transform the considered problem into an unconstrained optimization problem. We then employ Broyden-Fletcher-Goldfarb-Shanno (BFGS) method to solve the resulting unconstrained problem which helps reduce the complexity significantly, compared to conventional methods. Simulation results show the fast convergence of the proposed algorithm and substantial performance improvements over existing approaches.

Finite domination and Novikov homology over strongly Z-graded rings

Let L be a unital Z-graded ring, and let C be a bounded chain complex of finitely generated L-modules. We give a homological characterisation of when C is homotopy equivalent to a bounded complex of finitely generated projective L0-modules, generalising known results for twisted Laurent polynomial rings. The crucial hypothesis is that L is a strongly graded ring. 

Estimating quantum chromatic numbers

We develop further the new versions of quantum chromatic numbers of graphs introduced by the first and fourth authors. We prove that the problem of computation of the commuting quantum chromatic number of a graph is solvable by an SDP algorithm and describe an hierarchy of variants of the commuting quantum chromatic number which converge to it. We introduce the tracial rank of a graph, a parameter that gives a lower bound for the commuting quantum chromatic number and parallels the projective rank, and prove that it is multiplicative. We describe the tracial rank, the projective rank and the fractional chromatic numbers in a unified manner that clarifies their connection with the commuting quantum chromatic number, the quantum chromatic number and the classical chromatic number, respectively. Finally, we present a new SDP algorithm that yields a parameter larger than the Lovász number and is yet a lower bound for the tracial rank of the graph. We determine the precise value of the tracial rank of an odd cycle.

Représentations et fusion des algèbres de Temperley-Lieb originale et diluée

Les algèbres de Temperley-Lieb originales, aussi dites régulières, apparaissent dans de nombreux modèles statistiques sur réseau en deux dimensions: les modèles d'Ising, de Potts, des dimères, celui de Fortuin-Kasteleyn, etc. L'espace d'Hilbert de l'hamiltonien quantique correspondant à chacun de ces modèles est un module pour cette algèbre et la théorie de ses représentations peut être utilisée afin de faciliter la décomposition de l'espace en blocs; la diagonalisation de l'hamiltonien s'en trouve alors grandement simplifiée. L'algèbre de Temperley-Lieb diluée joue un rôle similaire pour des modèles statistiques dilués, par exemple un modèle sur réseau où certains sites peuvent être vides; ses représentations peuvent alors être utilisées pour simplifier l'analyse du modèle comme pour le cas original. Or ceci requiert une connaissance des modules de cette algèbre et de leur structure; un premier article donne une liste complète des modules projectifs indécomposables de l'algèbre diluée et un second les utilise afin de construire une liste complète de tous les modules indécomposables des algèbres originale et diluée. La structure des modules est décrite en termes de facteurs de composition et par leurs groupes d'homomorphismes. Le produit de fusion sur l'algèbre de Temperley-Lieb originale permet de «multiplier» ensemble deux modules sur cette algèbre pour en obtenir un autre. Il a été montré que ce produit pouvait servir dans la diagonalisation d'hamiltoniens et, selon certaines conjectures, il pourrait également être utilisé pour étudier le comportement de modèles sur réseaux dans la limite continue. Un troisième article construit une généralisation du produit de fusion pour les algèbres diluées, puis présente une méthode pour le calculer. Le produit de fusion est alors calculé pour les classes de modules indécomposables les plus communes pour les deux familles, originale et diluée, ce qui vient ajouter à la liste incomplète des produits de fusion déjà calculés par d'autres chercheurs pour la famille originale. Finalement, il s'avère que les algèbres de Temperley-Lieb peuvent être associées à une catégorie monoïdale tressée, dont la structure est compatible avec le produit de fusion décrit ci-dessus. Le quatrième article calcule explicitement ce tressage, d'abord sur la catégorie des algèbres, puis sur la catégorie des modules sur ces algèbres. Il montre également comment ce tressage permet d'obtenir des solutions aux équations de Yang-Baxter, qui peuvent alors être utilisées afin de construire des modèles intégrables sur réseaux.

(Des)igualdades de Género nas Organizações de Trabalho: o caso de uma autarquia local

Em Portugal, cerca de duas centenas de organizações estão empenhadas a criar e implementar Planos para a igualdade de homens e mulheres. Entre elas estão empresas públicas e privadas, autarquias, associações empresariais, organizações do setor terciário, associações de desenvolvimento, universidades, ministérios e outros departamentos governativos. A pesquisa que aqui se expõe inscreveu-se num projeto mais amplo de diagnóstico em realização na Câmara Municipal da Lousã, que se encontra a promover um Plano Municipal para a Igualdade. Nesse âmbito mostrou-se necessário fazer um diagnóstico interno à organização com uma perspetiva de género, quer em termos de desigualdades de género na composição e situação dos seus efetivos quer de forma a conhecer as representações das pessoas que trabalham na autarquia, em torno do fenómeno da (des)igualdade de mulheres e homens. Para a sua realização foi feita análise estatística a dados fornecidos pela organização, e aplicou-se um inquérito por questionário ao pessoal ao serviço da autarquia. Concluiu-se que estamos na presença do fenómeno da desigualdade em função do sexo na estrutura da organização traduzida pela segregação ocupacional e segregação vertical, sendo os homens que apresentam os maiores níveis de antiguidade, que justificarão, de certa forma, as disparidades salariais existentes. Confirmamos uma dualidade entre o ideal de mulher como mãe e dona-de-casa e o de mulher como pessoa independente, especialmente quando são evocadas as consequências da sua atividade profissional sobre os/as filhos/as e a vida familiar. O papel de cuidar surge assim como o obstáculo a conceções menos tradicionalistas e individualizadoras da identidade feminina que nos remete para uma mudança na atribuição do lugar social de homens e mulheres dentro e fora da família. Sobressai a valorização e enfatização da maternidade e do cuidado das crianças na identidade feminina; ao passo que aos homens se atribui uma maior valorização da atividade profissional. Esta constatação comprova a ambivalência e dicotomia de valores e atitudes entre uma fuga à convencional polarização entre papéis “masculinos” e “femininos” rígida e estereotipadamente definidos. / In Portugal, about two hundred organizations are committed to create and implement plans for men and women’s equality. These include public and private companies, local authorities, business associations, third sector organizations, development associations, universities, ministries and other governmental departments. The research exposed here is part of a broader diagnostic project taking placa in the City Hall, of Lousã which is promoting a Municipal Plan for Equality. In this context it was necessary to make an internal diagnosis to the organization from a perspective of gender, either in terms of gender inequalities in the composition and status of their workers or in order to know the workers representations around the phenomenon of women and men’s equality. To make it passible the organization provided statistical data which was analysed and subsequentaly a questionnaire was applied to the municipality staff. We concluded that there is the phenomenon of gender inequality in the structure of the organization namely occupational/professional segregation and vertical segregation, - men having the highest levels of seniority, which may justify in some way the existing wage gap. The study confirms a duality between the ideal of woman as a mother and housewife and the woman as an independent person, especially when the consequences suggested are related to their professional activity on their children and life family. The role of caring emerges as the obstacle to less traditionalist conceptions of female identity and individualization, which leads us to talk about a change of the social position of men and women within and outside the family. It points out the valuation and emphasizing of motherhood and care in female identity, whereas men are given a greater appreciation of the professional activity. This conclusion confirms the ambivalence and dichotomy of values and attitudes between escape from the conventional polarization between rigid and stereotypically defined roles of "male" and "female".

Os Efeitos da Avaliação Psicológica em Crianças com Dificuldades de Aprendizagem

O presente estudo de caso agregado teve como objetivo primordial avaliar em que medida os recursos terapêuticos utilizados durante o tempo de avaliação psicodiagnóstica (psicométrica e projetiva) das crianças encaminhadas para o serviço de psicologia escolar, tem impacto positivo na criança em processo de avaliação, no duplo plano comportamental e cognitivo. O protocolo da investigação foi composto por: desenho de família, WISC-III e CAT, com recurso a algumas sessões de ludoterapia. Os meios utilizados no processo de avaliação permitiram a superação de algumas dificuldades apresentadas pelas crianças, tendo sido, muito particularmente, identificados os contributos que a psicanálise e a psicologia psicodinâmica podem oferecer à psicopedagogia. / The main objective of this aggregated case study was the assessment of the impact of psycho-diagnostic evaluation (psychometric and projective testing) on the improvement of the school-aged children oriented to the cabinet of psychology of their school. The research protocol included: family picture test, WISC -III and CAT, plus some play therapy sessions. Some of the children overcame part of the learning and behavioral difficulties after the evaluation period. Such a result proves, most particularly, the contributions of psychoanalysis and psychodynamic psychology to psycho-pedagogy.

Núcleo Psicótico numa Psicose em Potencial Complexo de Mãe Morta e Psicose Branca: um estudo de caso

Este estudo teve como objetivo principal explorar dois conceitos importantes na teoria do psicanalista francês André Green: complexo de mãe morta e psicose branca. A decatexia provocada pelo afastamento emocional materno (complexo de mãe morta), induz um vazio interior (angústia branca). Esta sensação de vazio, de paragem, uma depressão sem afetos e a alucinação negativa, são manifestações da psicose branca (estrutura matriz onde se observa o núcleo da psicose sem que esta necessariamente se manifeste). O método utilizado foi o estudo de caso, de um sujeito do sexo masculino em regime de internamento. Os instrumentos de avaliação incluem a técnica projetiva de Rorschach (aplicada no início e no final do internamento) e o Thematic Apperception Test (aplicado no início do internamento). Através do material colhido em contexto de acompanhamento individual e das técnicas projetivas observaram-se pontos de contacto entre o conceito de psicose branca de Green, falso self de Winnicott e as personalidades “as if” de Helene Deutsch. A morte metafórica da mãe, o seu afastamento emocional, poderá estar na origem destas perturbações, onde se observa o núcleo da psicose. Nestas situações clínicas, em que o vazio interno predomina, a prática psicoterapêutica requer um posicionamento particular do clínico, que não deve estar nem muito próximo (sentido como intrusivo) nem muito distante (sentido como abandónico) do seu paciente. / This work had the purpose of exploring two important concepts in the theory of the French psychoanalyst André Green: the dead mother complex and the blank psychosis. The decathexis caused by a maternal emotional withdrawal (dead mother complex) induces an internal void (blank anguish). This feeling of emptiness, stoppage, a depression without affects and the negative hallucination are manifestations of blank psychosis (a matrix structure where one can observe the psychotic kernel, even though without having a manifest psychosis). The applied method was the case study, with a young male institutionalized subject, and to support it we used the Thematic Apperception Test (applied in the early phases of treatment) and the Rorschach projective technique (applied at the beginning and ending of the treatment). Through the data collected in the therapeutic sessions and the projective techniques applied, we observed points of contact between blank psychosis, Winnicott`s False Self and Helene Deutsch “as if” personalities. The mother’s metaphorical death, her emotional withdrawal, could be in the genesis of these disturbances, where we can observe the psychotic kernel. When we are dealing with this kind of patient, where the internal void prevails, the psychotherapeutic technique requires a special positioning from the therapist in relation to the patient, that shouldn’t be too close (experienced as intrusive), nor too distant (experienced with feelings of abandonment).

La elección del modelo de gestión en la cooperativas españolas

El objetivo del trabajo es analizar los diferentes modelos de gestión que pueden presentar las sociedades cooperativas. Tras una descripción de los modelos monista y dualista, así como de las distintas variantes que puede presentar este último modelo, se analizan los factores determinantes de su elección. Los factores analizados son: el tamaño, la edad y la actividad de la cooperativa. El análisis empírico ha sido realizado a partir de una muestra de empresas cooperativas españolas. Los resultados obtenidos muestran que el modelo dualista se utiliza, fundamentalmente en empresas grandes, de mayor edad y cuya actividad es la industria o los servicios.

Live Work: The Impact of Direct Encounters in Statutory Child and Family Social Wor

The aim of this research project was to examine the impact of direct work on practitioners in the field of statutory child protection. The author’s premise was that this work was anything but straightforward and that surprisingly, given the intense scrutiny on Children’s Services following a child death, there was little research into the day-to-day practice of front line staff. The aim was to explore whether psychoanalytic theory could be useful in understanding and making sense of the social work task. Data was collected through observation and semi-structured interviews in one Local Authority Child in Need team over a period of six months. The findings indicated that practitioners experienced direct work with some individuals and families as profoundly disturbing and that this affected them physiologically as well as psychologically. These effects persisted over time and appeared very difficult for the workers to process or articulate. This could be expressed through embodied or non-verbal communication in the interview. Practitioners appeared to be ‘inhabited’ by particular clients, suggesting phenomena such as projective identification were in operation. The intensity and persistence of the impact on the practitioners appears to be directly related to the quality, nature and intensity of the psychic defences functioning for the particular client. Significantly, the research indicated that when practitioners were dealing with the negative and disturbing projections from the (adult) clients it seemed from the data that the focus on the child would slip so that the child appeared to recede from view. Symptoms experienced by the practitioners were akin to trauma and research and theory on primary and secondary trauma were considered. Other issues raised included shame, which affects the clients, practitioners and the organisation and the meaning and implications of this are explored. Links between neuroscience and projective identification are addressed as well as the role of the organisation, particularly as a container for these toxic and disturbing encounters.

Problems in Algebraic Vision

Thesis (Ph.D.)--University of Washington, 2016-08

Holographic Tools for Probing the Dynamics of Strongly Coupled Field Theories

Thesis (Ph.D.)--University of Washington, 2016-08

Fluctuations in and out of equilibrium: Thermalization, quantum measurements and Coulomb disorder

This purely theoretical thesis covers aspects of two contemporary research fields: the non-equilibrium dynamics in quantum systems and the electronic properties of three-dimensional topological insulators. In the first part we investigate the non-equilibrium dynamics in closed quantum systems. Thanks to recent technologies, especially from the field of ultracold quantum gases, it is possible to realize such systems in the laboratory. The focus is on the influence of hydrodynamic slow modes on the thermalization process. Generic systems in equilibrium, either classical or quantum, in equilibrium are described by thermodynamics. This is characterized by an ensemble of maximal entropy, but constrained by macroscopically conserved quantities. We will show that these conservation laws slow down thermalization and the final equilibrium state can be approached only algebraically in time. When the conservation laws are violated thermalization takes place exponential in time. In a different study we calculate probability distributions of projective quantum measurements. Newly developed quantum microscopes provide the opportunity to realize new measurement protocols which go far beyond the conventional measurements of correlation functions. The second part of this thesis is dedicated to a new class of materials known as three-dimensional topological insulators. Also here new experimental techniques have made it possible to fabricate these materials to a high enough quality that their topological nature is revealed. However, their transport properties are not fully understood yet. Motivated by unusual experimental results in the optical conductivity we have investigated the formation and thermal destruction of spatially localized electron- and hole-doped regions. These are caused by charged impurities which are introduced into the material in order to make the bulk insulating. Our theoretical results are in agreement with the experiment and can explain the results semi-quantitatively. Furthermore, we study emergent lengthscales in the bulk as well as close to the conducting surface.

Sasakian quiver gauge theories and instantons on cones over lens 5-spaces

We consider SU(3)-equivariant dimensional reduction of Yang Mills theory over certain cyclic orbifolds of the 5-sphere which are Sasaki-Einstein manifolds. We obtain new quiver gauge theories extending those induced via reduction over the leaf spaces of the characteristic foliation of the Sasaki-Einstein structure, which are projective planes. We describe the Higgs branches of these quiver gauge theories as moduli spaces of spherically symmetric instantons which are SU(3)-equivariant solutions to the Hermitian Yang-Mills equations on the associated Calabi-Yau cones, and further compare them to moduli spaces of translationally-invariant instantons on the cones. We provide an explicit unified construction of these moduli spaces as Kahler quotients and show that they have the same cyclic orbifold singularities as the cones over the lens 5-spaces. (C) 2015 The Authors. Published by Elsevier B.V.

Natureza morta...edifício com vida: uma arquitetura sustentável para o Serviço de Verificação de Óbitos

Sustainability in buildings, while reducing the impact on the environment, contributes to the promotion of social welfare, to increase the health and productivity of occupants. The search for a way of build that meets the aspirations and development of humanity without, however, represent degradation of the environment, has become the great challenge of contemporary architecture. It is considered that the incorporation of principles that provide a sustainable building with careful choices of design solutions contribute to a better economic and thermal performance of the building, as well as functional and psychological comfort to its users. Based on this general understanding, this paper presents an architecture project aimed to health care whose the solutions adopted follow carefully the relevant legislation and sets his sights on the theme of sustainability. The methodology began with studies on the themes of verification service of deaths, sustainability and those application in construction developed through research in academic studies and analysis of architectural projects, using them like reference for the solutions adopted. Within the project analysis was performed a visit to the verification service of deaths in the city of Palmas in Tocantins, subsidizing information that, plus the relevant legislation, led to functional programming and pre-dimensional of the building to be designed. The result of this programming environments were individual records with information from environmental restrictions, space required for the development of activities, desirable flow and sustainability strategies, that can be considered as the first product of relevance of the professional master's degree. Finally we have outlined the basic design architecture of a Verification Service of Death SVO/RN (in portuguese), whose process of projecting defined as a guiding line of work four points: the use of bioclimatic architecture as the main feature projectual, the use of resources would provide minimal harm to the environment, the use of modulation and structure to the building as a form of rationalization and finally the search for solutions that ensure environmental and psychological comfort to users. Importantly to highlight that, besides owning a rare theme in literature that refers to architectural projects, the whole project was drawn up with foundations in projective criteria that contribute to environmental sustainability, with emphasis on thermal performance, energy efficiency and reuse of rainwater

Symmetric Interior Penalty DG Methods for the Compressible Navier-Stokes Equations II: Goal--Oriented A Posteriori Error Estimation

In this article we consider the application of the generalization of the symmetric version of the interior penalty discontinuous Galerkin finite element method to the numerical approximation of the compressible Navier--Stokes equations. In particular, we consider the a posteriori error analysis and adaptive mesh design for the underlying discretization method. Indeed, by employing a duality argument (weighted) Type I a posteriori bounds are derived for the estimation of the error measured in terms of general target functionals of the solution; these error estimates involve the product of the finite element residuals with local weighting terms involving the solution of a certain dual problem that must be numerically approximated. This general approach leads to the design of economical finite element meshes specifically tailored to the computation of the target functional of interest, as well as providing efficient error estimation. Numerical experiments demonstrating the performance of the proposed approach will be presented.