This thesis describes methods for using spectral interferometry for the complete space-time characterisation of few-cycle near-infrared femtosecond pulses and extreme ultraviolet (XUV) attosecond pulses produced via high harmonic generation (HHG). Few-cycle pulses tend to exhibit one or more of the following: (1) an octave-spanning bandwidth, (2) a highly modulated spectrum and (3) space-time coupling. These characteristics, coupled with the desire to measure them in a single-shot (to characterise shot-to-shot fluctuations) and in real-time (for online optimisation and control) causes problems for conventional characterisation techniques. The first half of this thesis describes a method, based on a spatially encoded arrangement for spectral phase interferometry for direct electric-field reconstruction (SEA-SPIDER). SEA-SPIDER is demonstrated for sub-10fs pulses with a central wavelength near 800nm, a bandwidth over 350nm, and a pulse energy of several nano-Joules. In addition, the pulses exhibit a modulated spectrum and space-time coupling. The spatially-dependent temporal intensity of the pulse is reconstructed and compared to other techniques: interferometric frequency-resolved optical gating (IFROG) and spectral phase interferometry for direct electric field reconstruction (SPIDER). SEA-SPIDER will prove useful in both femtoscience, which requires accurate knowledge of the space-time character of few-cycle pulses, and in HHG, which requires the precise knowledge of the driving pulse for seeding into simulations and controlling the generation process itself. Pulses arising from HHG are known to exhibit significant space-time coupling. The second half of this thesis describes how spectral interferometry may be performed to obtain the complete space-time nature of these fields via the use of lateral shearing interferometry. Finally, it is shown, via numerical simulations, how to extend the SPIDER technique for temporal characterisation of XUV pulses from HHG by driving the process with two spectrally-sheared driving pulses. Different experimental configurations and their applicability to different laser systems are discussed. This method recovers the space-time nature of the harmonics in a single shot, thus reducing the stability constraint currently required for photoelectron based techniques and may serve as a complimentary method for studying interactions of XUV attosecond pulses with matter.

In the past decade, cooperative communications has been emerging as a pertinent technology for the current and upcoming generations of mobile communication infrastructure. The indispensable benefits of this technology have motivated numerous studies from both academia and industry on this area. In particular, cooperative communications has been developed as a means of alleviating the effect of fading and hence improve the reliability of wireless communications. The key idea behind this technique is that communication between the source and destination can be assisted by several intermediate nodes, so-called relay nodes. As a result, cooperative communication networks can enhance the reliability of wireless communications where the transmitted signals are severely impaired because of fading. In addition, through relaying transmission, communication range can be extended and transmit power of each radio terminal can be reduced as well. The objective of this thesis is to analyze the system performance of cooperative relay networks integrating advanced radio transmission techniques and using the two major relaying protocols, i.e., decode-and-forward (DF) and amplify-and-forward (AF). In particular, the radio transmission techniques that are considered in this thesis include multiple-input multiple-output (MIMO) systems and orthogonal space-time block coding (OSTBC) transmission, adaptive transmission, beamforming transmission, coded cooperation, and cognitive radio transmission. The thesis is divided into an introduction section and six parts based on peer-reviewed journal articles and conference papers. The introduction provides the readers with some fundamental background on cooperative communications along with several key concepts of cognitive radio systems. In the first part, performance analysis of cooperative single and multiple relay networks using MIMO and OSTBC transmission is presented wherein the diversity gain, coding gain, outage probability, symbol error rate, and channel capacity are assessed. It is shown that integrating MIMO and OSTBC transmission into cooperative relay networks provides full diversity gain. In the second part, the performance benefits of MIMO relay networks with OSTBC and adaptive transmission strategies are investigated. In the third part, the performance improvement with respect to outage probability of coded cooperation applied to opportunistic DF relay networks over conventional cooperative networks is shown. In the fourth part, the effects of delay of channel state information feedback from the destination to the source and co-channel interference on system performance is analyzed for beamforming AF relay networks. In the fifth part, cooperative diversity is investigated in the context of an underlay cognitive AF relay network with beamforming. In the sixth part, finally, the impact of the interference power constraint on the system performance of multi-hop cognitive AF relay networks is investigated.

Aim of the thesis is to analyze the ability of media to provide a sense of ontological security to their users. Changes, related to the transformation of traditional society into a modern society caused in the opinion of Anthony Giddens a weakening of the sense of ontological security of individuals. Such an outcome was a result of the space-time distanciation and individuals opting out of social systems as an impact of some globalization processes. Mass media in the modern society work as a main factor of social integration and differentiation. The ability to construct the sense of ontological security among its recipients is attributing in the field of television studies attributed to the traditional medium, television. But some basic characteristics of television broadcast and the role of television in households have changed with a digital television transition. Employing the methods of qualitative sociological research I will analyze whether new media have the potential to substitute television in the role of providing the sense of ontological security among its users. Powered by TCPDF (www.tcpdf.org)

[pt] Nesta dissertação são investigadas situações em que se faz necessária a sobreposição de informações digitais ao ambiente físico em que o usuário está, uma condição proporcionada pela utilização do recurso da Realidade Aumentada (RA). São consideradas, na pesquisa, aplicações da tecnologia que empregam a técnica de Video See-Through (VST) para utilização em celulares. São apresentadas diferentes definições de RA, delimitando-se conceitos tangentes à tecnologia, tais como Realidade Virtual e Computação Ubíqua, para promover uma discussão acerca das definições levantadas. Em seguida, se apresentam algumas soluções, mais encontradas no mercado, de aplicativos de RA para celular, analisando-se os impactos da utilização de ferramentas específicas no seu processo de criação e desenvolvimento. Considerando-se ainda aspectos sociais e filosóficos inerentes à tecnologia, busca-se uma melhor compreensão dos conceitos-base de espaço, tempo e realidade a que a RA recorre para operar, a fim de subsidiar a discussão acerca da tecnologia e criar o embasamento teórico para as análises subsequentes. / [en] This dissertation investigates situations that require the overlay of digital information to the user environment, a condition provided by the use of Augmented Reality (AR) technology. In the research, there are considered applications of the technology that uses the Video See-Through (VST) technique on mobile phones. The dissertation presents different definitions of AR, delimiting tangent concepts such as Virtual Reality and Ubiquitous Computing, to arouse a discussion about the definitions. Then, it presents some of the mobile applications most used in the market, analyzing the impact on using some specific tools in its creation and development process. Considering further social and philosophical aspects inherent to the technology, it seeks to better understand the basic concepts of space, time and reality that the AR uses to operate, in order to support the discussion about the technology and to create the theoretical basis for subsequent analysis.

Les méthodes de décomposition de domaine en espace ont prouvé leur utilité dans le cadre des architectures parallèles. Pour les problèmes d’évolution en temps, il est nécessaire d’introduire une dimension supplémentaire de parallélisme dans la direction du temps. Ceci peut alors être couplé avec des méthodes de type optimisé Schwarz waveform relaxation. Nous nous intéressons dans cette thèse aux méthodes directes de décomposition en temps. Nous en étudions particulièrement deux. Dans une première partie nous étudions la méthode de produit tensoriel, introduite par R. E. Lynch, J. R. Rice, et D. H. Thomas in 1963. Nous proposons une méthode d’optimisation des pas de temps, basée sur une étude d’erreur en variable de Fourier en temps. Nous menons cette étude sur les schémas d’Euler et de Newmark pour la discrétisation en temps de l’équation de la chaleur. Nous présentons ensuite des tests numériques établissant la validité de cette approche. Dans la seconde partie, nous étudions les méthodes dites de Bloc, introduites par Amodio et Brugnano en 1997. Nous comparons diverses implémentations de la méthode, basées sur différentes approximations de l’exponentielle de matrice. Nous traitons l’équation de la chaleur et l’équation des ondes, et montrons par une étude numérique bidimensionnelle la puissance de la méthode. / Domain decomposition methods in space applied to Partial Differential Equations (PDEs) expanded considerably thanks to their effectiveness (memory costs, calculation costs, better local conditioned problems) and this related to the development of massively parallel machines. Domain decomposition in space-time brings an extra dimension to this optimization. In this work, we study two different direct time-parallel methods for the resolution of Partial Differential Equations. The first part of this work is devoted to the Tensor-product space-time method introduced by R.E. Lynch, J. R. Rice, and D. H. Thomas in 1963. We analyze it in depth for Euler and Crank-Nicolson schemes in time applied to the heat equation. The method needs all time steps to be different, while accuracy is optimal when they are all equal (in the Euler case). Furthermore, when they are close to each other, the condition number of the linear problems involved becomes very big. We thus give for each scheme an algorithm to compute optimal time steps, and present numerical evidences of the quality of the method. The second part of this work deals with the numerical implementation of the Block method of Amodio and Brugnano presented in 1997 to solve the heat equation with Euler and Crank- Nicolson time schemes and the elasticity equation with Euler and Gear time schemes. Our implementation shows how the method is accurate and scalable.

educação com o objetivo de compreender a re-produção das relações sociais de produção que se generalizam até o cotidiano e produzem e são produzidas por um espaço e tempo separados. Falamos em fundamentos sociais porque seria impossível pensar em qualquer mudança qualitativa da educação sem pensarmos numa mudança social. Este é um estudo desenvolvido através da Teoria da Implicação, utilizada por Remi Hess em suas análises de instituições e teve como base teórica-metodológica as obras de Henri Lefebvre, Karl Marx e os Situacionistas, principalmente Guy Debord e Raoul Vaneigem, sendo a dialética essencial para que se priorizasse o movimento conflituoso de uma totalidade. A linguagem dessa pesquisa é definida pelos conceitos lefebvrianos e situacionistas, daí conceitos como o de re-produção das relações sociais de produção, possívelimpossível, tempo-espaço do vivido, sob(re)vida são de extrema importância no desenvolvimento da dissertação. A escola, como objetividade que re-produz as relações sociais, na lógica da economia, tem como sujeito a educação, que torna-se sinônimo de escola e sua contradição, deteriorando a educação. Na realidade urbana atual, lutarmos por uma boa escola é lutar por mais desigualdade transvestida de igualdade formal, por divisão do trabalho, por uma sociedade de classes, enfim, é lutar pela reificação. A escola urbana cada vez mais faz parte do cotidiano, que é um nível do fenômeno urbano, e nessa repetição do cotidiano a escola e a educação tem as suas rupturas. Este é um momento em que se torna necessário discutir os limites da escola e da educação numa conjuntura em que a alienação social permite a re-produção de uma sociedade onde seu meio e seu fim é a economia e não a felicidade das pessoas. Apenas sob(re)viver, que no conceito apresentado por Raoul Vaneigem significa a negação da vida, não é aceitável e por isso queremos uma educação que seja para a vida. / This research establishes elements of the social foundations of the school and education in order to understand the re-production of social relations of production which generalizes to everyday life and produces and is produced by a separated space and time. We talk about social foundations because it would be impossible to think of any qualitative change in education without thinking about social change. This is a study developed based on the Theory of Implication, used by Remi Hess in his analysis of institutions. The study was theoretically and methodologically directed by the studies of Henri Lefebvre, Karl Marx and the Situationists, especially Guy Debord and Raoul Vaneigem, being dialectic the most essential basis so the conflicting movement of totality would arise. The language of this study is defined by concepts by Lefebvre and the Situationists, so concepts such as re-production of social relations of production, possible-impossible, lived space-time, survival, are of utmost importance in the development of this dissertation. The school as an objectivity that re-produces social relations, in the logic of the economy, has the education as a subject that becomes synonymous with school and in this movement its its contradiction and deterioration. In the current urban reality, fight for the right of a good school is fight for more inequality disguised as formal equality, division of labor, class society, in short, it is fighting for reification. The urban school is increasingly becoming a part of everyday life, which is a level of the urban phenomenon, and this repetition in school and education have rupture moments. This is the moment when it becomes necessary to discuss the limits of school and education in an environment where social alienation enables the re-production of a society where economy is its means and its end and not people\'s happiness. Survival is a concept developed by Raoul Vaneigem meaning the negation of life. Survival is not acceptable, we want education for life.

Nesta pesquisa procuramos estabelecer as bases teóricas e práticas da Internacional Situacionista e de dois de seus principais teóricos, Guy Debord e Raoul Vaneigem. Para aprofundar a compreensão, fomos em busca das origens desse grupo no Letrismo, na Internacional Letrista e Movimento por uma Bauhaus Imaginista, em uma tentativa de estabelecer uma trajetória. O início, no Letrismo, se estabelece como vanguarda artística, para logo quebrar com a perspectiva de uma proposta estética e realizar um aprofundamento de caráter marxista na crítica à cultura e ao urbanismo, na forma metodológica do desvio e da deriva e na construção de situações, a partir dos anos da Internacional Letrista. O processo de Decomposição da cultura faz com que alguns grupos se reúnam em uma nova internacional, desta vez Situacionista, com uma proposta inicial de revolução cultural, na e contra Decomposição. O envolvimento de Guy Debord com outros teóricos marxistas como Henri Lefebvre, radicaliza uma crítica da vida cotidiana e tira do foco uma discussão sobre cultura. O resultado é desenvolvimento do conceito de espetáculo, forma mais desenvolvida da sociedade produtora de mercadorias, e a centralização da questão do fetiche na crítica. Uma possibilidade de debate entre uma práxis revolucionária da vida cotidiana e a centralidade do fetiche da mercadoria nos parece necessária no momento atual da Geografia. / This research sought to establish the theoretical and practical bases of the Situationist International and two of its leading theorists, Guy Debord and Raoul Vaneigem. To deepen understanding, we were in search of the origins of this group in Lettrism, Lettrist International and the International Movement for an Imaginist Bauhaus, in an attempt to establish a trajectory. The beginning, in Lettrism, establishes himself as the artistic vanguard, soon to break with the prospect of an aesthetic proposal and make a deeper exploration in the marxist ideas, in order to make a critique of culture and urbanism with the methodological form of the detournement, the dérive and the construction of situations, since the years of the Lettrist International. The process of Decomposition of the culture causes some groups to join in a new International, Situationist this time, with an initial proposal of cultural revolution, inside and against Decomposition. Guy Debord\'s involvement with other marxist theorists such as Henri Lefebvre, the radical critique of everyday life takes the focus from the discussion about culture. The result is the development of the concept of spectacle, most developed form of commodity-producing society, and centered on the critical question of the fetish. A possibility for discussion between a revolutionary praxis of everyday life and the centrality of the fetish seems necessary at this moment in Geography.

Le recours à des simulations numériques pour l’étude de l’influence des paramètres d’entrée (matériaux, chargements, conditions aux limites, géométrie, etc.) sur les différentes quantités d’intérêt en soudage (contraintes résiduelles, distorsion, etc.) s’avère trop long et coûteux vu l’aspect multi-paramétrique de ces simulations. Pour explorer des espaces paramétriques de grandes dimensions, avec des calculs moins coûteux, il parait opportun d’utiliser des approches de réduction de modèle. Dans ce travail, d’une façon a posteriori, une stratégie non-intrusive est développée pour construire les abaques dédiées aux études paramétriques du soudage. Dans une phase offline, une base de données (‘snapshots’) a été pré-calculée avec un choix optimal des paramètres d'entrée donnés par une approche multi-grille (dans l’espace des paramètres). Pour explorer d’autres valeurs de paramètres, une méthode d’interpolation basée sur la variété Grassmannienne est alors proposée pour adapter les bases réduites espace-temps issues de la méthode SVD. Cette méthode a été constatée plus performante que les méthodes d’interpolation standards, notamment en non-linéaire. Afin d’explorer des espaces paramétriques de grandes dimensions, une méthode de type décomposition tensorielle (i.e. HOPGD) a été également étudiée. Pour l’aspect d’optimalité de l’abaque, nous proposons une technique d’accélération de convergence pour la HOPGD et une approche ‘sparse grids’ qui permet d’échantillonner efficacement l’espace des paramètres. Finalement, les abaques optimaux de dimension jusqu’à 10 à précision contrôlée ont été construits pour différents types de paramètres (matériaux, chargements, géométrie) du procédé de soudage. / The use of standard numerical simulations for studies of the influence of input parameters (materials, loading, boundary conditions, geometry, etc.) on the quantities of interest in welding (residual stresses, distortion, etc.) proves to be too long and costly due to the multiparametric aspect of welding. In order to explore high-dimensional parametric spaces, with cheaper calculations, it seems to be appropriate to use model reduction approaches. In this work, in an a posteriori way, a non-intrusive strategy is developed to construct computational vademecum dedicated to parametric studies of welding. In an offline phase, a snapshots database is pre-computed with an optimal choice of input parameters given by a “multi-grids” approach (in parameter space). To explore other parameter values, an interpolation method based on Grassmann manifolds is proposed to adapt both the space and time reduced bases derived from the SVD. This method seems more efficient than standard interpolation methods, especially in non-linear cases. In order to explore highdimensional parametric spaces, a tensor decomposition method (i.e. HOPGD) has also been studied. For the optimality aspect of the computational vademecum, we propose a convergence acceleration technique for HOPGD and a “sparse grids” approach which allows efficient sampling of the parameter space. Finally, computational vademecums of dimension up to 10 with controlled accuracy have been constructed for different types of welding parameters (materials, loading, geometry).

Esta pesquisa apresenta um sistema automático para extrair dados de tráfego veicular a partir do pós-processamento de vídeos. Os parâmetros macroscópicos e microscópicos do tráfego são derivados do diagrama espaço-tempo, que é obtido pelo processamento das imagens de tráfego. A pesquisa fundamentou-se nos conceitos de Visão Computacional, programação em linguagem C++ e a biblioteca OpenCV para o desenvolvimento do sistema. Para a detecção dos veículos, duas etapas foram propostas: modelagem do background e segmentação dos veículos. Uma imagem sem objetos (background) pode ser determinada a partir das imagens do vídeo através de vários modelos estatísticos disponíveis na literatura especializada. A avaliação de seis modelos estatísticos indicou o Scoreboard (combinação de média e moda) como o melhor método de geração do background atualizado, por apresentar eficiente tempo de processamento de 18 ms/frame e 95,7% de taxa de exatidão. A segunda etapa investigou seis métodos de segmentação, desde a subtração de fundo até métodos de segmentação por textura. Dentre os descritores de textura, é apresentado o LFP, que generaliza os demais descritores. Da análise do desempenho desses métodos em vídeos coletados em campo, conclui-se que o tradicional método Background Subtraction foi o mais adequado, por apresentar o melhor tempo de processamento (34,4 ms/frame) e a melhor taxa de acertos totais com 95,1% de média. Definido o método de segmentação, foi desenvolvido um método para se definir as trajetórias dos veículos a partir do diagrama espaço-tempo. Comparando-se os parâmetros de tráfego obtidos pelo sistema proposto com medidas obtidas em campo, a estimativa da velocidade obteve uma taxa de acerto de 92,7%, comparado com medidas de velocidade feitas por um radar; por outro lado, a estimativa da taxa de fluxo de tráfego foi prejudicada por falhas na identificação da trajetória do veículo, apresentando valores ora acima, ora abaixo dos obtidos nas coletas manuais. / This research presents an automatic system to collect vehicular traffic data from video post-processing. The macroscopic and microscopic traffic parameters are derived from a space-time diagram, which is obtained by traffic image processing. The research was based on the concepts of Computer Vision, programming in C++, and OpenCV library to develop the system. Vehicle detection was divided in two steps: background modeling and vehicle segmentation. A background image can be determined from the video sequence through several statistical models available in literature. The evaluation of six statistical models indicated Scoreboard (combining mean and mode) as the best method to obtain an updated background, achieving a processing time of 18 ms/frame and 95.7% accuracy rate. The second step investigated six segmentation methods, from background subtraction to texture segmentation. Among texture descriptors, LFP is presented, which generalizes other descriptors. Video images collected on highways were used to analyze the performance of these methods. The traditional background subtraction method was found to be the best, achieving a processing time of 34.4 ms/frame and 95.1% accuracy rate. Once the segmentation process was chosen, a method to determine vehicle trajectories from the space-time diagram was developed. Comparing the traffic parameters obtained by the proposed system to data collected in the field, the estimates for speed were found to be very good, with 92.7% accuracy, when compared with radar-measured speeds. On the other hand, flow rate estimates were affected by failures to identify vehicle trajectories, which produced values above or below manually collected data.

Este estudo apresenta um processo de pesquisa-ação desenvolvido num espaço/tempo intrainstitucional, destinado para a formação permanente dos professores-formadores de um curso de licenciatura em Química, de uma universidade privada do interior do Rio Grande do Sul. Esses docentes assumiram a sua prática como parâmetro para a análise e reflexão no seu processo contínuo de formação em serviço. Este trabalho teve como objetivo analisar as concepções epistemológicas e educacionais dos professores-formadores sobre o ensinar e o aprender, visando a compreender quais racionalidades fundamentam as ações desses docentes. Ao mesmo tempo, compreender se o espaço/tempo existente contribui para que mudanças ocorram nas ações dos professores-formadores, no sentido de uma construção de processos de ensino e aprendizagem que viabilizem o desenvolvimento intelectual dos educandos e a constituição desses na dimensão crítico-reflexiva. O processo de pesquisa envolveu dez professores-formadores e o professor/pesquisador, todos integrantes do Núcleo de Educação Química (NEQ), espaço/tempo intrainstitucional constituído para que esses profissionais desenvolvam processos reflexivos, especialmente, instrumentalizando-os para uma reflexão na, sobre e após a ação. Os dados analisados resultam de um estudo, de caráter qualitativo, situado no contexto da investigação-ação, produzidos com base em entrevistas semiestruturadas, realizadas de forma individual, gravadas em áudio e, também, em encontros realizados no NEQ, com a participação de todos os pesquisados, gravados em formato audiovisual, durante o segundo semestre de 2014 A análise dos dados deu-se com base nos procedimentos da Análise Textual Discursiva (ATD). A pesquisa mostra que esse processo de interação e diálogo que se desenvolve no espaço/tempo denominado NEQ, em que os professores-formadores concretizam processos reflexivos, socializam saberes, analisam e refletem sobre as práticas pedagógicas com seus pares se constitui em prática importante para promover novos estágios de compreensão aos sujeitos-atores do processo educativo, contribuindo para a problematização de saberes e reconfiguração da ação docente. Ainda, o estudo indica que reflexões produzidas no coletivo dos professores proporcionam a constituição de um processo de permanente ressignificação do ser e fazer docente, permitindo que a discussão de questões de natureza epistemológica e pedagógica da ação, existente, tradicionalmente, em grupo restrito de educadores, aconteça com o conjunto de professores-formadores, tanto das disciplinas de características pedagógicas, quanto daquelas de conhecimento específicos da área de química Portanto, ancorando-se em teóricos como Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), dentre outros, argumenta-se em favor da necessidade de espaços/tempos intrainstitucionais para a formação continuada do professor-formador na dimensão crítico-reflexiva, em todos os cursos de graduação ou áreas do saber que congregam educadores atuantes em cursos de graduação. Defende-se que o debate sobre questões de natureza epistemológicas e pedagógicas da ação docente não pode ficar atrelado à vontade de professores interessados. À medida que o educador se constitui um professor-formador, passa a ser obrigação de todos os envolvidos no curso de graduação estabelecer tal compreensão e fazê-la avançar, do contrário, não haverá mudanças significativas e não ocorrerá alteração na racionalidade que norteia a formação, em especial, dos futuros professores da educação básica. / This study presents a process of research-action developed in an intra-institutional space/time, intended for a permanent training of teacher-trainers of a Chemistry teaching degree course, of a private university in upstate Rio Grande do Sul. These teachers have taken on their practice as a parameter for the analysis and the reflection in their continuous process of training in service. This project aimed to analyze the epistemological and educational conceptions of teacher-trainers about the teaching and the learning, aiming to comprehend which rationalities base the actions of these teachers. At the same time, comprehending if the existing space/time contributes so that changes may take place in the actions of the teacher-trainers, in the sense of building teaching and learning processes that enable the intellectual development of students and their constitution in a critical and reflective dimension. The researching process involved ten teacher-trainers and the teacher/researcher, all members of the Núcleo de Educação Química (NEQ), intra-institutional space/time constituted so that these professionals may develop reflective processes, especially, instrumentalizing them for a reflection in, about and after the action. The analyzed data results from a qualitative study, situated in the context of the investigation-action, produced based on semi-structured interviews, performed individually, recorded in audio and, also, in gatherings that happened in NEQ, with the participation of all researched, recorded in audiovisual format, during the second semester of 2014. This analysis was performed based on the procedures of the Textual Discursive Analysis (TDA) This research shows that this interaction and dialogue process that is developed in the space/time called NEQ, in which the teacher-trainers concretize reflective processes, socialize knowledge, analyze and reflect about pedagogical practices with their pairs is an important practice in order to promote new stages of comprehension to the individuals-actors of the educational process, contributing to the problematization of knowledge and reconfiguration of the teaching action. Moreover, this study indicates that reflections produced among the teachers provide the constitution of a permanent process of re-signification of the teacher's being and doing, allowing the discussion of matters of epistemological and pedagogical nature of the action, existing, traditionally, in a restricted group of educators, to happen in the group of teacher-trainers, in subjects of pedagogical features, as well as those of specific knowledge in the Chemistry field. Therefore, based on theorists as Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), among others, are favorable to the need of intra-institutional space/times for the continuous training of the teacher-trainer in the critical-reflective dimension, in undergraduate courses or knowledge areas that congregate acting educators in undergraduate courses. It is defended that the debate about epistemological and pedagogical matters of the teaching action cannot be linked to the will of interested teachers. As the educator becomes a teacher trainer, it becomes mandatory that all involved in the undergraduate course establish such comprehension and make it move forward, otherwise, there won't be meaningful changes and there won't be changes in the rationality that guides the training, especially, of future teachers of basic education.