57 resultados para modos de plasmon (modo TM01)


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This dissertation is about an Education which is made concrete through orality and gestuality of the elderly joking masters of the territory of Mato Grande/RN and proposes a reflection about the exchange between these two knowledges and school education. Thus, it presents the following objectives: identifying the joking elderly in the region; recording their life experiences related to the jokes of the tradition and the way they realize such references at present; besides investigating and recording educative practices which consider the elderly s jokes at the present education. The investigation is supported by the metaphor in the making of a quilt as a methodological resource in the actions of measurement, choice of patches, sewing and binding off. The mapping of the territory of Mato Grande/RN has enabled the identification of seventeen joking elderly people. It considers and records their experiences with the popular amusements and from them, it discusses the ways through which the oral tradition in Mato Grande may be recognized in four categories/actions, namely, narrating, singing, dancing and getting old, which are analyzed under the studies by authors like Benjamin, Zumthor, Almeida, Porpino, among others. Finally, it also focuses the relation between the elderly, the knowledge of the tradition and the systemized education. It describes and articulates educative actions able to connect the knowledge by the joking elderly people and the knowledges taught at school, possibilities of concretization of a rebinding of knowledges which might bring orality and writing, the new and the old, science and tradition close to each other

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In the historical-cultural perspective, the drawing is processed by means of a shared and complex way, under diverse relations with the other and with the immersed signs of the culture. That is, something constituted by the social interactions and that can modify the structure of the psychological functions, therefore as socialized sign, propitiates the incorporation of the functions socially. In this way, the figuration carrier sensitive and established meanings historically disclosing the shared experiences and the ways of the subject to think and perceive the world. Such reflections gave shape to the main problem of this research: how to think over about the drawing at the school to incide in the reconstruction of the childs imaginative language? Under such perspective, this work deals with the interactions in the production process of the drawing of the children in a context of teach-Iearning of the elementary school having as goal to analyze the interactions established in the cIassroom in the process of production of the drawings; to propose situations of learnings that favor the advance graphical expression of the students; and to identify in the interactive games some relations between body expression and drawing. For its accomplishment, it was opted for the construction process based in the collaborative investigation by the fact to propitiate negotiations, sharing and confrontation of ideas, becoming possible a joint construction of the knowledge. For this research, the researcher and the collaborating teacher, as well as the involved children, become themselves into co-authors of the context studied. As locus of the research, it was chosen a first cycle class, with 30 students, from Municipal School Profª. Emília Ramos (Natal/RN - Brazil), whose election took in account the fact of this school to constitute in a promotional space of reflections and professional development of teachers in service and, at the same time, for presentinglimitations theoretic- methodological in the field of teaching for Arts. In the process of the research, it was perceived that the children with the support of the verbal language formulates meanings on the seen and imagined object, printing lines and forms that if overlap to the physiological aspects of the visual perception. That is, the drawing discloses a reality appraised, enriched for the picked up vision of the image, but the meanings established for the author, or observer who becomes it perceivable and identified. In the systemizing situations, it was observed that the teaching-Iearning process of the drawing, implies a co-construction between teachers and learners. And, moreover, the necessity to interlace emotion and cognition by means of plastic-corporal interactions that foment drawing experiences, whose process concurs for the imagenative reconstruct of the apprentices

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The so-called Dual Mode Adaptive Robust Control (DMARC) is proposed. The DMARC is a control strategy which interpolates the Model Reference Adaptive Control (MRAC) and the Variable Structure Model Reference Adaptive Control (VS-MRAC). The main idea is to incorporate the transient performance advantages of the VS-MRAC controller with the smoothness control signal in steady-state of the MRAC controller. Two basic algorithms are developed for the DMARC controller. In the first algorithm the controller's adjustment is made, in real time, through the variation of a parameter in the adaptation law. In the second algorithm the control law is generated, using fuzzy logic with Takagi-Sugeno s model, to obtain a combination of the MRAC and VS-MRAC control laws. In both cases, the combined control structure is shown to be robust to the parametric uncertainties and external disturbances, with a fast transient performance, practically without oscillations, and a smoothness steady-state control signal

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This work presents a theoretical and numerical analysis using the transverse resonance technique (TRT) and a proposed MTRT applied in the analysis of the dispersive characteristics of microstrip lines built on truncated isotropic and anisotropic dielectric substrates. The TRT uses the transmission lines model in the transversal section of the structure, allowing to analyze its dispersive behavior. The difference between TRT and MTRT consists basically of the resonance direction. While in the TRT the resonance is calculated in the same direction of the metallic strip normal axis, the MTRT considers the resonance in the metallic strip parallel plane. Although the application of the MTRT results in a more complex equivalent circuit, its use allows some added characterization, like longitudinal section electric mode (LSE) and longitudinal section magnetic mode (LSM), microstrips with truncated substrate, or structures with different dielectric regions. A computer program using TRT and MTRT proposed in this work is implemented for the characterization of microstrips on truncated isotropic and anisotropic substrates. In this analysis, propagating and evanescent modes are considered. Thus, it is possible to characterize both the dominant and higher order modes of the structure. Numerical results are presented for the effective permittivity, characteristic impedance and relative phase velocity for microstrip lines with different parameters and dimensions of the dielectric substrate. Agreement with the results obtained in the literature are shown, as well as experimental results. In some cases, the convergence analysis is also performed by considering the limiting conditions, like particular cases of isotropic materials or structures with dielectric of infinite size found in the literature. The numerical convergence of the formulation is also analyzed. Finally, conclusions and suggestions for the continuity of this work are presented

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The precision and the fast identification of abnormalities of bottom hole are essential to prevent damage and increase production in the oil industry. This work presents a study about a new automatic approach to the detection and the classification of operation mode in the Sucker-rod Pumping through dynamometric cards of bottom hole. The main idea is the recognition of the well production status through the image processing of the bottom s hole dynamometric card (Boundary Descriptors) and statistics and similarity mathematics tools, like Fourier Descriptor, Principal Components Analysis (PCA) and Euclidean Distance. In order to validate the proposal, the Sucker-Rod Pumping system real data are used

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In this work is proposed an indirect approach to the DualMode Adaptive Robust Controller (DMARC), combining the typicals transient and robustness properties of Variable Structure Systems, more specifically of Variable Structure Model Reference Adaptive Controller (VS-MRAC), with a smooth control signal in steady-state, typical of conventional Adaptive Controllers, as Model Reference Adaptive Controller (MRAC). The goal is to provide a more intuitive controller design, based on physical plant parameters, as resistances, inertia moments, capacitances, etc. Furthermore, with the objective to follow the evolutionary line of direct controllers, it will be proposed an indirect version for the Binary Model Reference Adaptive Controller (B-MRAC), that was the first controller attemptting to act as MRAC as well as VS-MRAC, depending on a pre-defined fixed parameter

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Amongst the results of the AutPoc Project - Automation of Wells, established between UFRN and Petrobras with the support of the CNPq, FINEP, CTPETRO, FUNPEC, was developed a simulator for equipped wells of oil with the method of rise for continuous gas-lift. The gas-lift is a method of rise sufficiently used in production offshore (sea production), and its basic concept is to inject gas in the deep one of the producing well of oil transform it less dense in order to facilitate its displacement since the reservoir until the surface. Based in the use of tables and equations that condense the biggest number of information on characteristics of the reservoir, the well and the valves of gas injection, it is allowed, through successive interpolations, to simulate representative curves of the physical behavior of the existing characteristic variable. With a simulator that approaches a computer of real the physical conditions of an oil well is possible to analyze peculiar behaviors with very bigger speeds, since the constants of time of the system in question well are raised e, moreover, to optimize costs with assays in field. The simulator presents great versatility, with prominance the analysis of the influence of parameters, as the static pressure, relation gas-liquid, pressure in the head of the well, BSW (Relation Basic Sediments and Water) in curves of request in deep of the well and the attainment of the curve of performance of the well where it can be simulated rules of control and otimization. In moving the rules of control, the simulator allows the use in two ways of simulation: the application of the control saw software simulated enclosed in the proper simulator, as well as the use of external controllers. This implies that the simulator can be used as tool of validation of control algorithms. Through the potentialities above cited, of course one another powerful application for the simulator appears: the didactic use of the tool. It will be possible to use it in formation courses and recycling of engineers

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The aluminothermic reduction consists in an exothermic reaction between a metallic oxide and aluminum to produce the metal and the scum. The extracted melted metal of that reaction usually comes mixed with particles of Al2O3 resulting of the reduction, needing of subsequent refine to eliminate the residual impure as well as to eliminate porosities. Seeking to obtain a product in powder form with nanometric size or even submicrometric, the conventional heat source of the reaction aluminothermic , where a resistor is used (ignitor) as ignition source was substituted, for the plasma, that acts more efficient way in each particle of the sample. In that work it was used as metallic oxide the niobium pentoxide (Nb2O5) for the exothermal reaction Nb2O5 + Al. Amounts stoichiometric, substoichiometric and superestoichiometric of aluminum were used. The Nb2O5 powder was mixed with aluminum powder and milled in planetarium of high energy for a period of 6 hours. Those powders were immerged in plasm that acts in a punctual way in each particle, transfering heat, so that the reaction can be initiate and spread integrally for the whole volume of the particle. The mixture of Nb2O5 + Al was characterized through the particle size analysis by laser and X-ray diffraction (DRX) and the obtained product of reaction was characterized using the electronic microscopy of sweeping (MEV) and the formed phases were analyzed by DRX. Niobium powders with inferior sizes to 1 mm were obtained by that method. It is noticed, through the analysis of the obtained results, that is possible to accomplish the aluminothermic reduction process by plasma ignition with final particles with inferior sizes to the original oxide

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To obtain a process stability and a quality weld bead it is necessary an adequate parameters set: base current and time, pulse current and pulse time, because these influence the mode of metal transfer and the weld quality in the MIG-P, sometimes requiring special sources with synergistic modes with external control for this stability. This work aims to analyze and compare the effects of pulse parameters and droplet size in arc stability in MIG-P, four packets of pulse parameters were analysed: Ip = 160 A, tp = 5.7 ms; Ip = 300 A and tp = 2 ms, Ip = 350 A, tp = 1.2 ms and Ip = 350 A, tp = 0.8 ms. Each was analyzed with three different drop diameters: drop with the same diameter of the wire electrode; droplet diameter larger drop smaller than the diameter of the wire electrode. For purposes of comparison the same was determined relation between the average current and welding speed was determined generating a constant (Im / Vs = K) for all parameters. Welding in flat plate by simple deposition for the MIG-P with a distance beak contact number (DBCP) constant was perfomed subsequently making up welding in flat plate by simple deposition with an inclination of 10 degrees to vary the DBCP, where by assessment on how the MIG-P behaved in such a situation was possible, in addition to evaluating the MIG-P with adaptive control, in order to maintain a constant arc stability. Also high speed recording synchronized with acquiring current x voltage (oscillogram) was executed for better interpretation of the transfer mechanism and better evaluation in regard to the study of the stability of the process. It is concluded that parameters 3 and 4 exhibited greater versatility; diameters drop equal to or slightly less than the diameter of the wire exhibited better stability due to their higher frequency of detachment, and the detachment of the drop base does not harm the maintenance the height of the arc

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The growing demand in the use of hybrid composite materials makes it essential a better understanding of their behavior face of various design conditions, such as the presence of geometric discontinuities in the cross section of structural elements. This way, the purpose of this dissertation is a study of the mechanical response (strength and stiffness), modes (characteristics) of fracture and Residual Strength of an hybrid polymeric composite with and without a geometric discontinuity in its longitudinal section (with a reduction in the cross section) loaded by uniaxial tension. This geometric discontinuity is characterized by central holes of different diameters. The hybrid composite was fabricated as laminate (plate) and consisting of ortho-tereftalic polyester matrix reinforced by 04 outer layers of Jute fibers bidirectional fabrics and 01 central layer of E-glass bidirectional fabric. The laminate was industrially manufactured (Tecniplas Nordeste Indústria e Comércio Ltda.), obtained by the hand lay-up technique. Initially, a study of the volumetric density of the laminate was made in order to verify its use in lightweight structures. Also were performed comparative studies on the mechanical properties and fracture modes under the conditions of the specimens without the central hole and with the different holes. For evaluating the possible influence of the holes in the structural stability of the laminate, the Residual Strength of the composite was determined for each case of variation in hole diameter. As a complementary study, analyses of the macroscopic final fracture characteristic of the laminates were developed. The presence of the central hole of any sizes, negatively changed the ultimate tensile strength. Regarding the elastic modulus, moreover, the difference found between the specimens was within the range of tests displacement, showing the laminate stability related to the stiffness

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The development of non-linear controllers gained space in the theoretical ambit and of practical applications on the moment that the arising of digital computers enabled the implementation of these methodologies. In comparison with the linear controllers more utilized, the non -linear controllers present the advantage of not requiring the linearity of the system to determine the parameters of control, which permits a more efficient control especially when the system presents a high level of non-linearity. Another additional advantage is the reduction of costs, since to obtain the efficient control through linear controllers it is necessary the utilization of sensors and more refined actuators than when it is utilized a non-linear controller. Among the non-linear theories of control, the method of control by gliding ways is detached for being a method that presents more robustness, before uncertainties. It is already confirmed that the adoption of compensation on the region of residual error permits to improve better the performance of these controllers. So, in this work it is described the development of a non-linear controller that looks for an association of strategy of control by gliding ways, with the fuzzy compensation technique. Through the implementation of some strategies of fuzzy compensation, it was searched the one which provided the biggest efficiency before a system with high level of nonlinearities and uncertainties. The electrohydraulic actuator was utilized as an example of research, and the results appoint to two configurations of compensation that permit a bigger reduction of the residual error

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In this work, we study the types of paraphrases used by the students of the Language and Literature Course when they reformulate a source text in the theoretical section of the monographs produced as texts for the conclusion of the course. Our main goal is to know how the process of textual reformulation takes place in the production of the monographic gender. From the used theoretical orientation (Fuchs,1982; 1994; Charaudeau and Maingueneau, 2006; Fávero et al, 2007; Hilgert, 1997, 2002, 2006; among others) we have worked with the paraphrase notion as an activity of discoursive reformulation, considering as the basic groundings the situation of communication and the subjects, or the wider context. In a more specific way, we have considered that the paraphrase performs alterations in the formal level, in the semantic level and in the functional level. Besides that, we sought to articulate the practice of paraphrasing to the gender of discourse in which it appears and to the contextual implications involved in the producing of the gender in question, and in doing so we were grounded in Baktin´s (2003) and Maingueneau´s (1998; 2001) postulates. For the analysis of the corpus that consists of 19 monographs, we have used the three categories defined by Hilgert (2002, 2006):expansion, condensation and parallelism as a way of identifying, describing and characterizing the types of paraphrases used by the students who produced the monographs when they take up Travaglia´s (1996) text about the language conceptions. The results show that the use of the paraphrastic parallelism (with 69.45 % in relation to only 18.41% of condensation and 12.13 % of expansion) was the most recurrent in the reformulations performed by the students who produced the monographs and this manifestation was characterized mainly by the lexical-semantic repetition of fragments of the source text. We have concluded that the high incidence of paraphrastic parallelism is an indication that the student does not have a command of the ways of production and circulation of the discoursive genders uttered in the academic-scientific realm

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This research deals with textualization issues present in educational forums in distance learning environment. The research aims to analyze textualization regarding communication practices between tutors and distance learning students. Specifically the research aims to verify if the educational forum is considered pertinent for knowledge construction as well as identify subject´s behavior in e-Proinfo environment. The research also aims to understand the dynamics of the teaching and learning techniques related to the forum´s printed material. This is done in order to acknowledge discourse on behalf of subjects through the presented educational assignments. In order to address the issue, the work dealt with the relations present in distance learning forums, the forms in which the assignments are made, the way social actors interact and how this debate happens in the virtual environment. The research emphasized an educational forum used in a higher education institution at Rio Grande do Norte/Brazil. Thus the research corpus is composed by messages that were posted in the forum in the module called computer material . This module is one of the last in a set of six modules that are part of The Basic Cycle for Media Training promoted by the Center for Distance Learning in a public university at Rio Grande do Norte/Brazil. The research deals with a qualitative type approach in the perspectives of Merriam (1988), Cresswell (1994) and Minayo (1996). In order to achieve this analysis, the research dealt with theoretical landmarks related to distance learning present in (Silva, 2008; Brait, 1993; Sperbe and Wilson, 1986; Marquesi and Elias 2008 as well as Xavier, 2005, amongst others. As for aspects related to media and technological perspectives present in the forum, the research dealt with (Baranov, 1989; Neuner, 1981; Kearsley and Moore, 1996). Textualization was dealt according to (Marcuschi, 2008; Costa Val, 2004) and the conceptions and functions regarding tutors was seen according to (Salgado, 2002). In the conclusion and recommendations it was seen that these discussions present relevant contributions to distance learning and go beyond the practical universe present in electronical interaction. In the final considerations it is pointed out that this research is relevant for areas such as applied linguistics and presents guidelines for those involved in continuous education and aim meaningful knowledge that is coherent with distance learning education

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The theme that fits the perspective of this thesis comes from the interest of treating, in the Epicurean corpus, about the importance of the body and its manners of realization for understanding the thought of Epicurus of Samos. Based on the inferences contained in the texts that remained from Epicurus, we did an analysis of the aspects that characterize Epicurism as a thought that makes repeated references to the body as an instance of sensitivity. It was necessary, therefore, to discuss how the body is linked to the possibility of thought, and how the latter can be admitted as a body element. It is further understood that the atomistic physics converges to the idea that asserts natural phenomena as likely to be contained and explained by the observations that come from the senses which are manifested through the body. For this reason, it was also pertinent to reflect on the admission of the body as a key element for the interpretation of Epicurean thought, even under the constitution of language. The Epicurean construction about body image was also used for the interpretation and questioning of the dynamics that define the relationships between individuals, characterizing the koinonía of the garden through the notion of corporeal unity. It was defined, therefore, that the characterization of the action field of individuals who lived in the Epicurean garden revolves around the use of logos, with the dialogues coming from the exercise of philosophy for therapeutic purposes, which were able to introduce a specific mode of political action marked by the absence of strange interests of the notion of philía

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O processamento de registros sísmicos é uma tarefa muito importante dentro da Geofísica e que representa um desafio permanente na exploração de petróleo. Embora esses sinais forneçam uma imagem adequada da estrutura geológica do subsolo, eles são contaminados por ruídos e, o ground roll é a componente principal. Este fato exige um esforço grande para o desenvolvimento de metodologias para filtragem, Dentro desse contexto, este trabalho tem como objetivo apresentar um método de remoção do ruído ground roll fazendo uso de ferramentas da Física Estatística. No método, a Análise em Ondeletas é combinada com a Transformada de Karhunen-Loève para a remoção em uma região bem localizada. O processo de filtragem começa com a Decomposição em Multiescala. Essa técnica permite uma representação em tempo-escala fazendo uso das ondeletas discretas implementadas a filtros de reconstrução perfeita. O padrão sísmico original fica representado em multipadrões: um por escala. Assim, pode-se atenuar o ground roll como uma operação cirúrgica em cada escala, somente na região onde sua presença é forte, permitindo preservar o máximo de informações relevantes. A atenuação é realizada pela definição de um fator de atenuação Af. Sua escolha é feita pelo comportamento dos modos de energia da Transformada de Karhunen-Loève. O ponto correspondendo a um mínimo de energia do primeiro modo é identificado como um fator de atenuação ótimo