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Uma experiência com a produção do texto literário : o cordel no processo de ensino e aprendizagem de língua portuguesa
(Universidade Federal de São Carlos, 2016-03-07) Alves, Renata Cristina; Brito, Maria Isabel de Moura; https://lattes.cnpq.br/7089011529083708; https://lattes.cnpq.br/6306203965057987
This study aims, in general, investigate and analyze the production of texts in the process of teaching and learning in the discipline of Portuguese, from working with cordel, while discursive gender. In this sense, the cordel, in front of their language use in public instances of communication, provides a cultural confrontation that leads the student to reflect on the context in which it appears. We chose first to make a rescue of the Portuguese language education – from grammar to the text – in order to highlight within this framework as the production of text was proposed in Portuguese language teaching. Then, the text in the classroom, as enunciation, brings in all are involved in a stated relationship, there is no excuse. Therefore, each answer will always responsive, which is linked to a chain of communication links in certain spheres of human activities, in this sense, every statement responds to a statement already made earlier and will be answered by an accomplished later. Cordel, in this context, as enunciation, involves a responsive attitude of students, which is positioned about the situations that occur in their daily lives and society. Thus, we understand the important medium which literature is for teaching, since is it who provides a unique view at the society, which, in the classroom, points to the external - life as it really is, with its shadows and lights, destabilizing. Also leading to reflection on the human being and therefore makes it more critical of those occurring in context. Moreover, cordel in the classroom also leads about the language dialogues large varieties, as well as use and operation of the language. From this, it was produced by eighth classrooms, cordel about various content and so we selected five texts: “Last Date”, “Corrupt”, “The Teacher”, “Rabbit and the Turtle” and “Come see the sunset”. Through the methodological course of the evidentiary paradigm, proposed by Carlo Ginzburg, search traces left in each text by means of characteristics for the genre, voices in the texts and the production context and then to understand the text production process in classroom.
Caracterização experimental e simulação computacional das deformações induzidas na fusão e cristalização do PTFE
(Universidade Federal de São Carlos, 2016-03-07) Sciuti, Vinicius Fiocco; Canto, Rodrigo Bresciani; https://lattes.cnpq.br/1316268411830615; Canto, Leonardo Bresciani; https://lattes.cnpq.br/7287108960864123; https://lattes.cnpq.br/0230261917656691
Polytetrafluoroethylene (PTFE) has excellent properties such as chemical inertness and useful mechanical properties at high and low temperatures. After melt, the PTFE viscosity is so high that the extrusion and injection processing are impracticable. Alternatively, the PTFE powder is cold pressed and sintered. During the sintering, heterogeneous temperature distributions may occur because of the low thermal conductivity of PTFE and induce thermal stresses. Cracks will be initiated if such stresses exceed the failure one. Considering the raw material cost (10 US$ kg−1)) and its density (2,2 g cm−3) cracks in the sintered PTFE may cause financial losses for the manufacturing industry, which justifies the studies about this process. The main mechanisms that cause permanent strains are the crystallinity change and the closure of voids from the pressing, which makes the satisfactory modeling of the PTFE sintering be complex. This work aims to characterize the strains assigned to the crystallinity changes and develop a computational model with such mechanism concerning the sintering of PTFE parts shaped by cold pressing. An experimental apparatus for the application of optical dilatometry assisted by Digital Image Correlation (DIC) was developed and used to estimate the specific volume of the amorphous and crystalline phases during sintering. The model was implemented using the UEXPAN AbaqusTM sub routine and model’s variables were obtained from literature and / or experimentally characterized. The model was validated by an experiment with thermal gradient induced strains in a PTFE specimen and the simulation results showed good correspondence with the DIC ones. For future works, it is suggested the improvement of the model implementing the void closure mechanism and the melting and crystallization kinetics, hence, the characterization of material properties in the temperature range of the process.
Cultivo de Dendrocephalus brasiliensis (Pesta, 1921) visando à aplicação em aquicultura
(Universidade Federal de São Carlos, 2016-03-07) Silva, Ricardo Augusto Custodio da; Melão, Maria da Graça Gama; https://lattes.cnpq.br/8342306603661310; https://lattes.cnpq.br/8019751585385627
The hatchery is now the main obstacle of aquaculture. Live food, especially zooplankton, is essential in the first life stages of fish. However, there are difficulties in obtaining sufficient biomass. The Anostraca Dendrocephalus brasiliensis, known as “branconeta”, has great potential for use in national aquaculture. In this study, experiments were conducted in controlled conditions in order to obtain: I) the best conditions for hatching of resistant cysts, evaluating the cyst density in the sediment, temperature and pH of the water, and cysts dehydration time; II) identification of the early stages of life, focusing on the length and time to maturity, and we also investigate the main factors that influence the development of the early stages and; III) semiintensive production, the organisms were grown during winter and summer, with two different diets and subsequent analysis of the biochemical composition of organisms grown in these conditions. Hatching occurs in low proportions, and is mainly influenced by the density of cysts present in the sediment, and show some tolerance to different levels of temperature and pH. The average time to reach adulthood was ten days and during the early stages, we observed that some individuals have delayed hatching. Among the environmental variables, temperature and conductivity play a major role in the growth during this period, along with the food, which must be provided from the third day. In semi-intensive farming conditions, we found that large amounts of food promote greater growth in length, both in summer and winter, however, during the winter, low amounts of food provide greater survival. In biochemical analysis, individuals grown with a low amount of food had higher proportion of protein, values higher than those found in Artemia sp. We also detected the presence of polyunsaturated fatty acids, which are of great interest in organisms to be used as live food for fish. In general, D. brasiliensis can be regarded as a suitable species for use in aquaculture due to: ease handling of cysts, since cysts present in the sediment are sufficient for obtaining large populations; growth rate and high tolerance to ambient changes, not requiring great efforts in keeping the culture medium and; nutritional quality, with high concentration of proteins and the presence of polyunsaturated fatty acids.
Estudo de um leito fixo de pequena espessura utilizando CFD
(Universidade Federal de São Carlos, 2016-03-07) Castro, Ubiranilson João de; Béttega, Rodrigo; https://lattes.cnpq.br/1379682125857376; Freire, José Teixeira; https://lattes.cnpq.br/2270677706718167; https://lattes.cnpq.br/0511237192868670
Studies carried out in fixed bed, a major experimental research equipment, use a simplified approach for assessing, for example, drying kinetics of various materials, known as thin-layer approach. For a given system can be encompassed in such an approach, the gas residence time in the system should be short enough so that it may be considered that the heat and mass balance between phases is quickly reached and moisture variation and temperature gas phase in the thin layer is negligible. However, some studies already show that structural parameters, the porosity, influence the speed profile of the behavior inside the bed, with a peak speed in the area close to the wall. Even with the advances in this field, obtaining measurements within the fixed bed are difficult to cause disturbances in its structure and changes in flow behavior, requiring the evaluation of the influence of the heat and mass transfer. Therefore, the analysis by techniques of Computational Fluid Dynamics (CFD) are shown as excellent usability for longer be applied in other similar complex systems that occur concurrent transfer mechanisms. In this context, the present study evaluated the drying process in a fixed bed of small thickness using the CFD technique (software ANSYS - FLUENT). For this study were tested with varying computational mesh refinement, analyzed results porosity distribution, air velocity, temperature and estimating the local mass transfer coefficient for the interior of a fixed bed dryer. The results show that should be used with caution thin layer approach because the energy available to the entire bed is not distributed uniformly, and the lower material layer receive more energy and get the greatest amount of heat in the gaseous phase in early stages of the dryer operation. The convective mass transfer coefficient indicates that the potential drying of such equipment varies as a function of position and time, mainly influenced by variations in system speed.
Avaliação da resistência ao desgaste de revestimentos de aços inoxidáveis modificados com boro e fabricados por Plasma com Arco Transferido (PTA)
(Universidade Federal de São Carlos, 2016-03-07) Sigolo, Erich; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://lattes.cnpq.br/7698860356694098
The discovery of new promising oil extraction sites in Brazil coast led to a great search for novel functionalized materials to withstand the demanding conditions from offshore oil exploitation. Stainless steels, such as duplex, superduplex and supermartensitc grades, are well established materials for applications in which a good balance of cost, mechanical strength and corrosion resistance is required. However, depending on the environment and working conditions, for instance in the risers (which connect the well head on the sea floor to the platform), stainless steels might present unfavorable wear resistance. Consequently, there are coating processes that can deposit thicker layers of wear resistant materials (also called hardfacing) used for applications in which wear conditions are demanding. Also, recent studies conducted in DEMa/UFSCar showed that boron addition in stainless steels composition led to the formation of borides which increased wear resistance. In this work, the microstructure and wear resistance of boron-modified stainless steels coatings, namely superduplex and supermartensitic with different boron additions, produced by Plasma Transferred Arc (PTA) were investigated. This welding process allows the deposition of thick and dense coatings with metallurgical bonding and very low dilution. Microstructural characterization revealed that the coatings were dendritic in all cases, however the amount of borides formed was significantly different. The wear resistance was evaluated by dry sand/rubber wheel and reciprocating pin-on-plate tests. The results showed different wear resistance depending on wear mechanism involved. Although, in both tests, the wear resistance presented by the boron-modified superduplex coating was far superior. The formation of hard borides and its higher phase fraction in the microstructure were responsible for the good wear performance.
Algoritmo genético embarcado aplicado à indução de operadores morfológicos
(Universidade Federal de São Carlos, 2016-03-07) Tognoli, Éttore Leandro; Pedrino, Emerson Carlos; https://lattes.cnpq.br/6481363465527189; https://lattes.cnpq.br/1563628701928365
The use of genetic algorithms, evolutionary strategies and genetic programming has been notoriously addressed in the areas of image processing and computer vision and has contributed with diverse results. However, this approach requires large computing power. Some academic papers bring these algorithms for the areas of embedded and dedicated systems, improving in this way the performance of algorithms and minimizing the computational cost. This design addresses the implementation of these algorithms applied to morphological processing of images using FPGAs and Verilog-HDL. The genetic algorithm is adapted for a more intuitive and simple implementation for the development of a dedicated hardware and it may contribute to reduce logical resources and enhance performece. Studies and tests carried out during the project showed good results for the proposed design.
Análise microlocal nas classes de Denjoy-Carleman
(Universidade Federal de São Carlos, 2016-03-07) Medrado, Renan Dantas; Hoepfner, Gustavo; https://lattes.cnpq.br/7742503790793940; https://lattes.cnpq.br/9403703489935356
Using a more general class of FBI transforms, introduced by S. Berhanu and J. Hounie in [16], we completely characterize regularity and microregularity in Denjoy-Carleman (non quasi analytic) classes, which includes the Gevrey classes and M. Chist FBI transform defined in [27] as examples. Using the classic FBI transform we completely describe the M—wave-front set of the boundary values of solutions in wedges W of hypo Denjoy-Carleman structures (M, V) (Definição 3.1.2) proving similar results first obtained by [1], [5], [13, 14], [35] and [43]. Inspired by [53], [56], [41] and [1] we introduce the notion of nonlinear Mizohata type equations and study microlocal Denjoy-Carleman regularity for solutions u of non linear equations, extending the main results of [1], [5], [13, 14], [35] and [43].
Previsão do posicionamento de partículas de nanosílica numa blenda polimérica imiscível e comprovação via turbidimetria
(Universidade Federal de São Carlos, 2016-03-07) Johansen, Luis Henrique Balista; Canto, Leonardo Bresciani; https://lattes.cnpq.br/7287108960864123; Canevarolo Júnior, Sebastião Vicente; https://lattes.cnpq.br/4153664441338178; https://lattes.cnpq.br/8114430529119286
The optical behavior of polymer systems with nanoparticles was studied in order to quickly assess the location of the nanoparticles in the immiscible polymer blend phases and interface using optical microscopy. The systems were designed taking into consideration microrheological and optical requirements. The morphology was a droplet-matrix phase, with particle size in the range of the visible light. Polystyrene and polycarbonate were chosen according to the parameters previously established, forming blends PS/PC with 95/5 %wt. Hydrophobic and hydrophilic silicas were chosen as nanoparticles, which were added to the blends in amounts of 0,5% and 1%. The melt blending procedure helped to set the nanoparticles at specific locations including within the dispersed phase, matrix phase and interphase. The morphology and the location of the nanoparticle were confirmed via transmission electron microscopy. The light scattering was measured via the normalized transmitted light intensity over temperature, overpassing the Tg of the two polymeric component. The PS/PC blends showed an increase in the light scattering, following a sigmoidal shape, in the temperature range of PS and PC Tg’s. The addition of the nanosilica forming PS/PC/Nanosilica systems greatly reduces the light scattering, particularly above the Tg of the PS phase. The use of hydrophilic nanosilica does not show any hysteresis upon comparing data from heating and cooling cycles. This type of silica stays mainly trapped within the PC particle, little interfering with the light scattering. On the other hand using hydrophobic nanosilica a clear hysteresis between heating and cooling portions is observed. The presence of the hydrophobic silica, located at the PS/PC interphase, interfere with the light scattering intensity at this interface, and can be used to identify its presence. The proposed procedure can be used to fast control the mixing process, thus improving the effective action of the nanoparticles in the final properties of the polymer systems.
Uma abordagem dirigida por modelos para distribuição tardia de aplicações
(Universidade Federal de São Carlos, 2016-03-07) Esperança, Vinicius Nordi; Lucrédio, Daniel; https://lattes.cnpq.br/9090396559596221; https://lattes.cnpq.br/2878349174376892
The need to improve software systems to adapt to the new technologies is a constant topic of research. As computing evolves, new challenges emerge and new solutions must be created. The increasing use of various types of devices for access to sites and software and the ease that the Internet provides the information access, force researchers to keep great efforts improving already developed applications, or even thinking of ways to facilitate the development of software to run on multiple devices. The general purpose of this master’s research was focused on this problem, distribute software systems initially designed to run on a single computer in order to eliminate many tasks that the developer thoroughly repeat this process. The approach allows developers to use the source code of any application and distribution models, perform the division of its software quickly in order to test different distributions without time cost. Using concepts of MDD (Model-Driven Development), analyzers and code generators, and concepts of microservices, it developed a partitioner that distributes the source code of an application on multiple servers, creating small services for each, making these services exchange information with each other while maintaining the functionality of the application intact. The partitioner gives flexibility to the programmer to choose the arrangement of classes among the services that will be created. Developers can then easily test different ways to distribute the code of the application without the need of having to develop services and communication between the new services. This approach was called late distribution. Experimental studies were performed to ensure the validity of the project. In total, five different tests were conducted in order to verify the creation of services would be performed as defined by the programmer. In all cases the result was satisfactory, allowing distribution of software code used between the designated servers.
Um modelo para estimativa do consumo de energia de desktops virtuais
(Universidade Federal de São Carlos, 2016-03-07) Bignatto Junior, Pedro Wilson; Senger, Hermes; https://lattes.cnpq.br/3691742159298316; https://lattes.cnpq.br/5949869749894579
The virtualization of computing resources is becoming increasingly frequent for several purposes. An example is desktop virtualization, in which the user’s workstation is virtualized, executed in a data center, and delivered to users as a service. Users can access their virtual desktops over the network, from anywhere, anytime, using simplified clients as smartphones or tablets. Besides mobility, desktop virtualization brings significant reduction in management costs and administration of desktops. In the present work we propose a model that estimates the energy consumption of a desktop virtualization service. The proposed model aims to assist decision-making on the provision of resources and improving energy efficiency. The model takes into account energy consumption during all the lifecycle of a virtualized desktop since the instantiation. From the experiments, applying the model, it was concluded that for applications with low transmission rate of frames and commands, such as a web browser, it is better to instantiate an VD instead of running as a local desktop. It happens because the energy cost of running is amortized through the sharing of resources between the various connected users into the server, in addition to the low cost of transmission. The best energy efficiency has been obtained as a result of instantiating an VD on a datacenter (DC) with acessible through a local area network (LAN), in which the energy consumption per bit transmission is suffucuently low to compensate energy cost of VD migration between different DCs.
Processamento remoto em solução para interação com ambientes arquitetônicos 3D através de tablets
(Universidade Federal de São Carlos, 2016-03-07) Rabello, Guilherme Picanço; Teixeira, Cesar Augusto Camillo; https://lattes.cnpq.br/1123376648713853; https://lattes.cnpq.br/6936352500632761
The evolution of Computer Graphics, supported by the computational development, enables increasingly advanced visual creations and promotes benefits to various areas such as: Art, architecture, Product Design, Visual Design, Games, Movies, Engineering, GIS and Medicine. However, the processing power needed for applications that require a high degree of realism, restricts the use of these applications to a small portion of the entire range of the computing devices in use by the population. Recently, the evolution of mobile network technologies brought a possible solution to the inability of most mobile devices in dealing with interactive applications and a high degree of realism. The solution is based on the remote processing of applications on servers with high processing capacity, and delivery of the images produced for mobile devices made by its conversion into video and streaming broadcasts. This master dissertation explores a remote processing solution for interacting with architectural environments through tablets. Emphasis was placed in: keeping high degree of realism, difficult to achieve due to the processing requirements in real-time interactive applications; the adaptation and combination of tools available in the market; and in mitigating latency through different ways of user interaction. The evaluation of the results was carried out in training sessions, interaction and interviews with volunteers.
Análise teórica-experimental de semicondutores / Mateus Meneghetti Ferrer
(Universidade Federal de São Carlos, 2016-03-07) Ferrer, Mateus Meneghetti; Longo, Elson; https://lattes.cnpq.br/9848311210578810; https://lattes.cnpq.br/6355560471517685
The rapid modernization of industrial and technological poles spurs the development of new materials, always in search of efficiency and low costs, given that the expression "new materials" does not relate just to the new classes or compounds never seen before but also to the structural modifications in materials already studied. In this context, research using theoretical and experimental models tends Researches using combined theoretical and experimental methods tend to be more and more commonly due to the better correlation between system characteristics and properties. However, a better interpretation can assists in the planning and developing of new materials. In the present study, a set of theoretical and experimental models were built in order to explain the properties and phenomena of semiconductors. The chosen materials were the α-Ag2WO4, β-Ag2MoO4, Co3O4, α- Fe2O3 and In2O3. Characterization techniques of X-Ray difraction, Rietveld refinament, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy were related with quantum mechanical calculations to a better understanding of the observed results. Theoretical results of band structure and density of states are in agreement with the experimental band gaps.The data showed a creation of new eletronic states on the forbiden region on the band gap due to the criation of structural defects, by means of a impurity or structural changes. The final models were used to a better explanation of the photoluminescent properties modifications. Quantum mechanical calculations were also used to the explanation of a phenomenon caused by electron bombing, which was observed in Ag2WO4 and Ag2MoO4 crystals. In this model, the Ag reduction results in its removal of the clusters generating the Ag metallic filaments on the material surface. Finally, it was created a new approach about the mapping and prediction of crystals morphology that serves as an experimental reference to the comparison between surface and final properties. The presented papers consist in an interdisciplinary research, from fundamental to applications and show how quantum chemical and other theoretical computational means can be used for an understanding of physical and chemical properties of materials for searching a rational materials design.