"Optical vortices are ubiquitous features of electromagnetic radiation that are often described as a destructive null in a beam of coherent light. Optical vortices may be created by a variety of different methods, one of which is by the use of a diffractive vortex mask, which is a plate of glass that has been etched in a spiral staircase pattern such that the thickness of the mask varies harmonically in the azimuthal direction. Light passing through the mask gains an azimuthal variation in phase due to the index mismatch between the glass substrate and the surrounding medium and thus an optical vortex is created. There is an implicit assumption that the light is spatially coherent, or in other words, that there is a definite phase relationship between each point in the beam. Optical vortices are not believed to occur in completely incoherent light where the term “phase” no longer holds any meaning. Optical vortices are also poorly understood in partially coherent light where statistics must be used to quantify the phase. The purpose of the research presented in this thesis was to determine how spatial coherence affects the transmission properties of the vortex phase mask. This research enabled us to create a coherence filtering technique based upon the vortex diffractive mask. In this dissertation I will demonstrate the usefulness of this filtering technique in two specific applications. First in the detection of forward-scattered light, where the un-scattered probe beam may blind a detector making detection of the scattered light extremely difficult. Second, in the enhanced resolution of two nearby objects, where the signal from one object may be lost in the glare of a brighter companion. This filtering technique has a wide field of possible applications including the detection of extra-solar planets, the detection of defects in laser optics, and improved methods in optical tomography."

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-01-10T11:34:26Z No. of bitstreams: 1 Edir Aparecido Morato.pdf: 2715191 bytes, checksum: ed9b2c2ee379f84f855e62cfc6a87a41 (MD5) / Made available in DSpace on 2017-01-10T11:34:26Z (GMT). No. of bitstreams: 1 Edir Aparecido Morato.pdf: 2715191 bytes, checksum: ed9b2c2ee379f84f855e62cfc6a87a41 (MD5) Previous issue date: 2017-12-13 / “Nos esforsamos au macimu… (We’ve made a great effort… – written with grammatical errors in Portuguese) to learn”, affirms Henrique, student from the 9th year of Primary School, regular modality, of a public school in the city of São Paulo. It is in that school context this bibliographical and empiric research aims to analyze the massification of the school teaching and its possible effects in learners in this part of the primary school process. The massification of the school teachingis understood as the quantitative expansion of the school process (ENGUITA, 1989), in order to teach innumerous students with a few teachers. In this sense, the objective of this study is to identify the teaching procedures that characterize school positions to the students according to their conditions of knowledge appropriation (CHARLOT, 2000; 2013). The methodology adopted arose from the classes observations based on the research question: which teaching procedures does a teacher use considering each student’s learning process? At the end of the observations, I proceeded with questionnaires and discussion groups with teachers and students. The information obtained by means of those resources was organized in charts and tables for further analysis. This qualitative work did not dispense the quantitative data, as well as the analysis of the curricular proposal of São Paulo education network and the involved teachers’ lesson plans. The results indicate that the effects originating from the massification compromise the teaching of knowledge and the development of competences and abilities when those do not correspond to the learners’ singularities and therefore, to the basic needs of the learning process / “Nos esforsamos au macimu” para aprender, assim afirma o Henrique, aluno no 9º ano do ensino fundamental, modalidade regular, de uma escola pública do município de São Paulo, na qual esta pesquisa bibliográfica e empírica objetiva analisar a massificação do ensino escolar e seus possíveis efeitos em educandos nesta etapa da escolaridade básica. Entende-se por massificação deste ensino a expansão quantitativa da escolarização (ENGUITA, 1989), no intuito de ensinar inúmeros alunos com poucos professores. Nesse sentido o objeto desse estudo são os procedimentos de ensino, que caracterizam posições escolares aos alunos conforme suas condições de apropriação de conhecimentos (CHARLOT, 2000; 2013). A metodologia adotada partiu da observação de aulas com base na seguinte questão de pesquisa: quais procedimentos de ensino um professor utiliza em vista da aprendizagem de cada educando? Ao final dessas observações prossegui com questionários e grupos de discussão com professores e alunos. As informações obtidas por meio destes recursos foram organizadas em quadros e tabelas para posterior análise. O trabalho, de caráter qualitativo, não prescindiu de dados quantitativos, bem como da análise da proposta curricular da rede de ensino paulistana e do planejamento de aulas dos professores envolvidos. Os resultados da pesquisa indicam que os efeitos oriundos da massificação comprometem o ensino de conhecimentos e o desenvolvimento de competências e habilidades quando estes não correspondem às singularidades dos educandos e, por conseguinte, às suas necessidades básicas de aprendizagem

Submitted by MARCELO BEZERRA DE MORAIS null (morais.mbm@gmail.com) on 2017-03-27T14:52:18Z No. of bitstreams: 1 Se um viajante... - digital_finalizado.pdf: 28591707 bytes, checksum: 4783e69e655cae282b0dba2efa61196c (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-03-28T19:11:11Z (GMT) No. of bitstreams: 1 morais_mb_dr_rcla.pdf: 28591707 bytes, checksum: 4783e69e655cae282b0dba2efa61196c (MD5) / Made available in DSpace on 2017-03-28T19:11:11Z (GMT). No. of bitstreams: 1 morais_mb_dr_rcla.pdf: 28591707 bytes, checksum: 4783e69e655cae282b0dba2efa61196c (MD5) Previous issue date: 2017-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A intenção desta pesquisa foi compreender e elaborar versões históricas, a partir de diversas perspectivas documentais e testemunhais, de como se deu a formação dos professores que ensinavam matemática no estado do Rio Grande do Norte, nas séries que correspondem aos atuais ensinos fundamental e médio, incluindo possíveis aspectos relacionados ao desenvolvimento desse processo de formação, antes e durante o período de criação dos quatro mais antigos cursos superiores que habilitavam professores em Matemática neste estado. Utilizamos como metodologia de pesquisa a História Oral, produzindo e analisando vinte narrativas e documentos acessados em arquivos públicos e privados. Seguindo uma perspectiva transdisciplinar, elaboramos compreensões sobre o processo “formação de professores de matemática” e constituímos narrativas segundo três disposições distintas mas interconectadas: a análise narrativa de narrativas, a análise de singularidades e a análise de convergências. O texto final desse movimento de pesquisa tem um estilo alternativo que pretende dialogar com as teorizações feitas. / The intention of this doctoral thesis is to sketch, from oral and written sources, some historical versions about the process in which Brazilian teachers from the state of Rio Grande do Norte were formed to teach in secondary schooling system. Our main methodological guide was given by Oral History and our research sources were, basically, twenty narratives and a set of written documents collected in public and particular archives. From these sources, following a transdisciplinary framework and three distinct bur interconnected analytical perspectives – the so called narrative analysis of narratives, the analysis of singularities and the analysis of convergences –, it was possible to build a comprehensive discourse on ”Math teachers formation” and, particularly, on “Math teachers formation in Rio Grande do Norte”. The final report composition follows an alternative style in order to emphasize the theorization that underlies all the research process. / FAPESP: 2014/05379-0 / CAPES: BEX 10083/14-6

The motion of neutral test particles, both massive and massless, in the space time of a charged source described by the Reissner-Nordström solution is studied. This solution is characterized by two parameters, mass and charge, which defines the horizons of the source. When the mass is larger than the charge, the solution describes a black hole, with two distinct horizons. When the mass and charge are equal there is an extremal black hole, and both horizons merge to one. Finally, when the charge is larger than the mass there is a naked singularity, with no horizon. The structure and properties of these different type of solution are presented and discussed. A general solution of the equations of motion is presented in function of the Weierstrass elliptic function ℘. In addition, the possible orbits for test particles are discussed, and the conditions for existence of closed, circular or escape orbits are presented. The classifications is made based on the particles energy, and the mass and charge of the source. We find that all mentioned orbits are allowed for the three different type of solutions. In particular, for extremal black holes and naked singularities, we find stable circular orbits located outside the event horizon and hence being visible for an external observer. / O movimento de partículas teste neutras, ambas massivas e sem massa, no espaço-tempo de uma fonte carregada descrita pela solução de Reissner-Nordström é estudada. Essa solução é caracterizada por dois parâmetros, massa e carga, que definem os horizontes da fonte. Quando a massa é maior que a carga tal solução descreve um buraco negro com dois horizontes distintos. Quando a massa e a carga são iguais há um buraco negro extremo, e ambos os horizontes se unem em um. Finalmente, quando a carga é maior que a massa, há uma singularidade nua, sem horizontes. A estrutura e as propriedades dessas diferentes soluções são apresentadas e discutidas. Uma solução geral da equação de movimento é apresentada em termos da função elíptica de Weierstrass, ℘. Além do mais as possiveis órbitas para uma partícula teste são discutidas, e as condições para existência de órbitas fechadas, circulares e de escape são apresentadas. A classificação é feita a partir da energia da partícula, e da massa e carga da fonte. Encontramos que todas as orbitas mencionadas são permitidas nos três diferentes tipos de soluções. Em partícular, para buracos negros extremos e singularidades nuas, encontramos órbitas circulares estáveis localizadas fora do horizonte de eventos e, consequentemente, sendo visível para observadores externos.

At a platform singularity, a parallel manipulator loses constraint. Adding redundant actuation in an existing leg or new leg can eliminate these types of singularities. However, redundant manipulators have been designed with little attention to frame invariant techniques. In this dissertation, physically meaningful measures for closeness to singularities in non-redundant manipulators are developed. Two such frameworks are constructed. The first framework is a constrained optimization problem that unifies seemingly unrelated existing measures and facilitates development of new measures. The second is a clearance propagation technique based on workspace generation. These closeness measures are expanded to include redundancy and thus can be used as objective functions for designing redundant actuation. The constrained optimization framework is applied to a planar three degree of freedom redundant parallel manipulator to show feasibility of the technique.

Šiuolaikinė organizacija, suburianti profesionalus bendrai veiklai, turi skirti didelį dėmesį savo veiklos socialiniams aspektams, tarp kurių svarbią vietą užima organizacijos kultūra. Švietimo organizacijos kultūros idėjai ir jos diegimo būdų problematikai pastaruoju metu yra skiriama nemažai dėmesio, universiteto, gimnazijos kultūra yra įvairių sričių mokslininkų tyrinėjama ir analizuojama, tačiau tyrimų duomenų apie bendrojo lavinimo mokyklos organizacijos kultūrą ir jos ypatumų sisteminį pagrindimą neteko aptikti. Kaip leidžia teigti daugelio autorių patirtis, mokyklų kultūros sisteminiai tyrimai yra aktualūs, nes gali ypač padėti mokykloms aptikti vystymosi rezervus netgi mokyklos kultūros tyrimo procesas gali tapti mokyklos veiklos tobulinimo priemone. Tyrimo objektas. Mokyklos kaip organizacijos kultūra. Tyrimo tikslas. Išanalizuoti mokyklos kultūros sampratą, atskleisti mokyklos kaip organizacijos kultūros ypatumus. Tyrimo metodai. Tyrimas vykdytas pasitelkus mokslinės informacijos šaltinių analizę, aprašomąją statistiką, anketinę mokytojų ir mokinių apklausą, sudarytą remiantis P. Jucevičienės, A. Poškienės, L. Kudirkaitės, N. Damansko (2000) klausimynu universiteto organizacijos kultūrai tirti. Tyrimo duomenys apdoroti Microsoft Excel kompiuterine programa. Tyrimo imtis. Tyrimas atliktas 2008 metų kovo mėnesį. Apklausoje dalyvavo dvi respondentų grupės: 166 – VII-X klasių mokiniai (iš kurių – 85 miesto vietovės ir 81 rajono vietovės mokyklų mokinys); 56 mokytojai... [toliau žr. visą tekstą] / Nowadays organisation rallying the professionals for common activities should pay great attention to social aspects of its activity, among which organisational culture takes an important place. Currently, a lot of attention is paid to the idea of educational organisation culture as well as problematic of introduction of related methods, culture of university, gymnasium is analysed and surveyed by scientists of diverse fields, however it was impossible to find any survey data related to organisational culture of general education school and systematic substantiation of singularities of the latter. Referring to the experience by many authors, systematic survey of school culture is relevant as it may help schools in establishing the development reserve, and even more the process of survey of school culture could become the measure for improvement of school activity. The object of the survey: The culture of school as organisation. The aim of the survey: To analyse the concept of school culture, to reveal singularities of culture of the school as organisation. The methods of the survey. The survey was conducted referring to the analysis of scientific information sources, descriptive statistics, interview of teachers and pupils with the help of questionnaires formed according to the questionnaire for survey of culture of university organisation by P. Jucevičienė, A. Poškienė, L. Kudirkaitė, N. Damanskas (2000). The survey data was processed with Microsoft Excel computer programme... [to full text]

In the field of singularly perturbed reaction- or convection-diffusion boundary value problems the research area of a priori error analysis for the finite element method, has already been thoroughly investigated. In particular, for mesh adapted methods and/or various stabilization techniques, works have been done that prove optimal rates of convergence or supercloseness uniformly in the perturbation parameter epsilon. Commonly, however, it is assumed that the exact solution behaves nicely in that it obeys certain regularity assumptions although in general, e.g. due to corner singularities, these regularity requirements are not satisfied. So far, insufficient regularity has been met by assuming compatibility conditions on the data. The present thesis originated from the question: What can be shown if these rather unrealistic additional assumptions are dropped? We are interested in epsilon-uniform a priori estimates for convergence and superconvergence that include some regularity parameter that is adjustable to the smoothness of the exact solution. A major difficulty that occurs when seeking the numerical error decay is that the exact solution is not known. Since we strive for reliable rates of convergence we want to avoid the standard approach of the "double-mesh principle". Our choice is to use reference solutions as a substitute for the exact solution. Numerical experiments are intended to confirm the theoretical results and to bring further insights into the interplay between layers and singularities. To computationally realize the thereby arising demanding practical aspects of the finite element method, a new software is developed that turns out to be particularly suited for the needs of the numerical analyst. Its design, features and implementation is described in detail in the second part of the thesis.

The main aim of this paper is proof that the reduction of the singularities of a generalized hypersurfaces agrees with a reduction of singularities of its separatrix; which is a generalization of the result presented in [8] by the first two authors. / El objetivo principal de este artículo es demostrar que la reduccióon de singularidades de una hipersupercie generalizada coincide con una reducción de singularidades de su separatriz; el cual es una generalización del resultado presentado en [8] por los dos primeros autores.

Les objectifs scientifiques de ces travaux de thèse reposent sur le développement d’une plateforme robotisée pour la réalisation d’un acte d’échographie à distance. Les contraintes de cet acte médical à distance ont conduit à la réalisation d’un robot sériel à cinq degrés de liberté. La présence d’une singularité centrale a conditionné la proposition d’une loi de commande cinématique pondérée dont l’objectif est d’assurer le meilleur suivi du geste médical et le maintien du plan ultrasonore à l’approche de la singularité. Cette loi de commande est basée sur une combinaison linéaire de l’inverse et de la pseudo-inverse de la matrice jacobienne de base du robot. Les réseaux haut débit sont nécessaires pour l’utilisation de la plateforme télé-opérée afin d’assurer une très bonne qualité des images échographiques reçues par l’expert. Cependant, ils sont soumis à de forts délais de transmission perturbant la stabilité du système robotique et le ressenti des interactions robot/patient. L’architecture de commande bilatérale passive proposée est basée sur le formalisme des variables d’ondes, et inclut les structures mécatroniques des postes maître et esclave, et les caractéristiques des liens de communication. Cette approche garantit, quels que soient les délais de transmission, la stabilité et la transparence de la plateforme télé-opérée. La prise en compte de l’ensemble des caractéristiques mécatroniques de la chaîne télé-opérée a permis de proposer une méthodologie pour l’adaptation d’impédance afin d’améliorer le rendu haptique au niveau du poste maître. Des expérimentations par satellite ont validé l’approche de la structure bilatérale et confirmé la stabilité et la transparence de la chaîne télé-opérée quels que soient les délais de communication. / The scientific objectives of this PhD thesis work are based on the development of a robotic platform used to perform tele-echography act via satellite link. The constraints of the remote tele-echography procedure led to the development of a 5-DOF serial robot. The presence of a central singularity has conditioned the proposal of a weighted kinematic control law to ensure a better monitoring of medical procedure and ultrasonic plan when approaching the singularity. This control law is based on a linear combination of the inverse and pseudo-inverse of the Jacobian matrix. Broadband networks are required to provide high quality ultrasound images to the medical expert. However, they are subject to high transmission delays disrupting the stability of the robotic system and rendering of robot/patient interactions. The passive bilateral control architecture proposed is based on the wave variables approach ; it includes the mechatronic master and slave characteristics, and the communication links characteristics. This approach ensures stability and transparency of the tele-operated platform whatever the transmission time delay. A methodology for impedance matching taking into account the characteristics of mechatronic tele-operated chain has improved haptic rendering at the station master. Satellite experiments have validated the proposed wave variables bilateral structure and confirmed the stability and transparency of the tele-operated chain for any communication delays.

Made available in DSpace on 2015-03-26T13:45:35Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1898009 bytes, checksum: 7ee3890dce9bee7dd59b31ebd52ed3a0 (MD5) Previous issue date: 2012-07-16 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / In this work, we study the graphs as invariants of stable Gauss maps from closed surfaces embedded in R3. We study the problem of realization of graphs by stable Gauss maps, emphasizing also cusp number of these maps. / Neste trabalho, estudamos os grafos como invariantes de aplicações de Gauss estáveis de superfícies fechadas mergulhadas em R3. Abordamos o problema de realização de grafos por aplicações de Gauss estáveis, enfatizando também o número de cúspides destas aplicações.