Estudo da sinterização de cavacos de aço ferritico

This research studies the sintering of ferritic steel chips from the machining process. Were sintered metal powder obtained from machining process chips for face milling of a ferritic steel. The chip was produced by machining and characterized by SEM and EDS, and underwent a process of high energy mill powder characterized also by SEM and EDS. Were constructed three types of matrixes for uniaxial compression (relation l / d greater than 2.5). The differences in the design of the matrixes were essentially in the direction of load application, which for cylindrical case axial direction, while for the rectangular arrays, the longer side. Two samples were compressed with different geometries, a cylindrical and rectangular with the same compaction pressure of 700 MPa. The samples were sintered in a vacuum resistive furnace, heating rate 20 °C / min., isotherm 1300 °C for 60 minutes, and cooling rate of 25 °C / min to room temperature. The starting material of the rectangular sample was further annealed up to temperature of 800 ° C for 30 min. Sintered samples were characterized by scanning electron microscopy, optical microscopy and EDS. The sample compressed in the cylindrical matrix did not show a regular density reflecting in the sintered microstructure revealed by the irregular geometry of the pores, characterizing that the sintering was not complete, reaching only the second phase. As for the specimen compacted in the rectangular array, the analysis performed by scanning electron microscopy, optical microscopy and EDS indicate a good densification, and homogeneous microstructure in their full extent. Additionally, the EDS analyzes indicate no significant changes in chemical composition in the process steps. Therefore, it is concluded that recycling of chips, from the processed ferritic steel is feasible by the powder metallurgy. It makes possible rationalize raw material and energy by manufacture of known properties components from chips generated by the machining process, being benefits to the environment

A importância da atividade física regular como estratégia complementar na promoção de resiliência de idosas e sua importância para suas vidas

O conceito de saúde, na concepção mais abrangente, é uma condição multidimensional de bem-estar físico, psicológico e social e não apenas a inexistência de enfermidades. Os benefícios da atividade física são tão relevantes quanto os benefícios psicológicos, porque ambos contribuem para a saúde. A literatura aponta um conjunto de ligações diretas e indiretas entre a atividade física e a qualidade de vida. Apesar destes benefícios, o processo de envelhecimento é caracterizado por grandes perdas biopsicossociais, que geram várias situações de adversidades que causam preocupação e podem colocar em risco a saúde do idoso. Deste modo, surge a resiliência como um conjunto de processos sociais e intrapsíquicos, que possibilitam o desenvolvimento saudável do idoso, mesmo diante de experiências negativas. Nesta direção, observou-se a necessidade de executar uma pesquisa de conhecimento multidisciplinar conciliando a Educação Física com a Psicologia, a Medicina, a Terapia Ocupacional e a Gerontologia, com o objetivo de investigar o efeito da atividade física sobre os níveis de resiliência em mulheres idosas, bem como conhecer a importância desta atividade para suas vidas. Para tanto, realizou-se um estudo comparativo descritivo, de caráter transversal. Assim sendo, 230 mulheres idosas foram divididas em dois grupos: ativas (n=115; 65,8±5,8 anos de idade), constituído por idosas matriculadas em um programa de atividade física orientada para idosos com período de prática igual ou superior a dois anos, e sedentárias (n=115; 69,2±7,2 anos de idade). Em seguida, foram submetidas à avaliação do nível de resiliência psicológica e da aptidão física (resistência muscular de membros superiores e inferiores, flexibilidade e resistência aeróbia). As idosas ativas apresentaram valores significativamente (p=0,001) maiores do fator 3 da resiliência psicológica quando comparados àqueles do grupo de idosas sedentárias, o qual está relacionado à autoconfiança e à capacidade de adaptação a situações diversas. Não foram observadas diferenças significativas (p>0,05) entre os grupos para os demais fatores (1 e 2). Quando comparados os testes de aptidão física com o nível de resiliência psicológica moderada (n=28) e alta (n=202) do fator 3, observou- se que idosas com nível de resiliência psicológica alta apresentaram maior flexibilidade (p=0,004). E para a avaliação da percepção da importância da atividade física para as idosas foi aplicado um questionário semiestruturado. A partir da Análise de Conteúdo proposto por Bardin (2009) os resultados foram: saúde/prevenção (85%), interação (47%), autonomia (40%), alegria/felicidade (33%), resiliência (33%), lazer (15%). E para avaliar a resiliência utilizou-se a Escala de resiliência de Wagnild e Young (1993). Quanto aos níveis de resiliência os resultados demonstraram que todas idosas apresentaram alto nível. Considerando os achados do presente estudo, sugere-se o emprego da atividade física como método de intervenção para melhora da saúde mental e, por conseguinte, da resiliência psicológica na população em questão, uma vez que os resultados apontam que idosas fisicamente ativas apresentam escores de resiliência psicológica superiores àquelas estratificadas como sedentárias. O resultado desse estudo possibilitou também concluir que a importância da atividade física parece estar relacionada, na sua maioria, às características de saúde/prevenção, interação social, autonomia, resiliência, alegria/felicidade e lazer. Além disso, as mulheres do presente estudo apresentaram um alto nível de resiliência quando comparado à tabela normativa

O aluno surdo em classe regular: concepções e práticas dos professores

Le texte se rapporte à une recherche sur les conceptions d enseignants concernant l inclusion scolaire d élèves sourds , et leurs ralations avec les pratiques qu ils développent dans les classe régulières. Elle a été conduite dans une école publique régulière appartenant à la commune de Assu RN, et dont le choix méthodologique a été une approche qualitative, du genre ethnographyque. La construction des données devient d un processus d observation, de l application d entretiens demi-structurés et de l analyse de documents, ayant pour sujets quatre enseignants des années initiales de l enseignement fondamental. L apport théorique de base a été la théorie socio-culturelle proposée par Vygotsky (2003 ; 2005), censée traduire la compréhension de l homme dans sa dimension historique et culturelle, et mettre en évidence l interaction sociale en tant que condition pour le développement des individus. Les données font connaître que les enseignants sujets de la recherche sont favorables à l inclusion scolaire des élèves sourds dans les classes régulières, néanmoins soulignent le besoin d un changement à l école pour que l inclusion devienne une réalité. Les enseignants sont d avis que l apprentissage des élèves sourds se fait d une façon qui met trop de temps, moyennant l utilisation de recours spécifiques, tels que l usage du langage des signes (Libras). Ils signalent les difficultés qu ils doivent faire face quand il s agit de travailler pédagogiquement avec ces élèves dans le quotidien, telles que : manque d un travail collectif à l école ; besoin d une formation spécialisée ; démonstration de sentiments de peur, ou préjugés de la part de quelques uns du personnel de l école , tout celà interférant directement dans leurs attitudes et leurs actions faces aux élèves ; manque d appui des instances administratives de l école ; absence de politiques consistentes pour guider l éducation sous un regard inclusif. Quant aux pratiques pédagogiques développées à l école, la recherche laisse voir que, par rapport à la présence des élèves sourds, très peu d adaptations y ont été introduites, d où se dégage que la planification des actions éducatives à l école se tourne, prioritairement, vers les élèves qui écoutent, c est-à-dire, vers un groupe apparemment homogène. On a constaté, en plus, qu il n existe pas à l école aucun professionnel habilité pour l établissement d un processus de communication avec les élèves sourds. Malgré ces difficultés, les enseignants avouent, quand même, que travailler avec ces élèves rapporte toujours des bénéfices, tels que la collaboration et le respect mutuels chez les élèves, l acquisition de nouveaux savoirs et l amélioration de la pratique pédagogique des enseignants

O educando com síndrome de down: um estudo sobre a relação entre pais e profissionais na escola regular

This work makes a documental analise about the relationship between families of Down syndrome students and professionals of who teach them, in order to improve the process of developing teaching-learning, in an inclusive perspective. For this, we use a qualitative approach, because we believe that the object of research is not a passive and neutral knowledge, since it has meanings and relationships whose can be better interpreted and understood by the researcher in a real and active situation. For the development of this research, a bibliographical review was made about the subject, and a case studied in two regular education schools, both of them at the city of Natal/RN, one public and another one particular. We work on these educational institutions with professionals and parents of Down syndrome students. As an instrument of building information we used a semi-structured interview and to analise the results a qualitative method. Crossing the stages, we noticed: the pedagogical coordinators who made up both analyzed schools showed interest about doing an effective work with parents, regardless of Educational Policy Project of each school, predict or not the participation on educational undertaken process; On teachers discourses, reporting the relationship with the family, we realize that one of those teachers try to keep a good relationship with parents, permeated by learning exchanges, guidance and knowledge, in relation to another one, even existing an apparent openness to dialogue, when parents have any suggestions or criticism, that attitude is not always well coming. From the parents interviews, we can emphasize, first of all, that both of them recognize the benefits of inclusion, with regard to socialization - in general from the coexistence with pairs and the process of teaching and learning, as shown in a consistent way. Regarding school meetings with teachers, the studied parents agree about importance of such appointments and try to attend them, besides the other events organized by the school, beyond keeping individual touch with the teacher, when necessary. They are always present, looking for get envolved in everything that happens at school, in order to know better what is being done, listening and may suggest alternatives to improving the educational process. We perceive, from the study undertaken, that although the school inclusion is not an easy process to be built, is something that could be achieved. For this, is necessary that professionals of education and families recognize their functions in the educational process and act jointly on this direction

A escrita e a criança com síndrome de Down: uma relação possível na escola regular

The school inclusion is based on respect for diversity and the belief that everyone has the capacity to learn and develop, for this the school needs to prepare itself to meet the differences and provide a meaningful learning for everyone, including those with Down syndrome. It is in the interaction with others that children develop their skills and exchange substantial experiences to learn the school and non school knowledge. Among the knowledge the school must offer students, there is one that is indispensable to the present society; the writing, because writing is a way to Interact, to communicate and to build autonomy to relate in society. Before exposed, the research that started this study aimed to investigate the level of the writing conceptualization of children with Down syndrome during the literacy process in a regular school of the private school network in the city of Natal/RN. For carrying out this study, initially we conducted a qualitative research, using the bibliographical as a methodological recourse, seeking to the deepening of information, based on the literature about the subject, which allowed us to collect data about people with Down syndrome, their education and the process of the writing acquisition. Later, a case study was performed, involving free observation in the room and interviews with teachers and children, trying to verify how this writing acquisition process occurs by children with Down syndrome. The data analyzed and information recorded demonstrated that the school inclusion, when taken seriously, benefits the learning of writing for children who have intellectual deficit, and, mainly, they develop in this environment and are able to learn to write, as long as their own pace are respected

Interações comunicativas entre uma professora e um aluno com transtorno invasivo do desenvolvimento na escola regular

Inclusion of students with autism in regular education settings is a topic that has not been much explored by the national scientific literature. This matter is complex and, due to the extent of various aspects involved, it is essential to delimitate a focus of investigation. The direction taken by this study was to evaluate the effects of an intervention program in the communicative interactions between a student with autism and his teacher in a regular classroom. Data were collected in an elementary private school, located in the city of Natal, Rio Grande do Norte during the 2010 academic school year. The study included a teacher and a non-vocal, 10-year-old student diagnosed with autism. A quasi-experimental A-B research design was employed. During the intervention program the teacher was trained to use Naturalistic Teaching Strategies and Alternative and Augmentative Communication (AAC) resources to increase the frequency of interactions with the student during three classroom routines (entry time, snack and pedagogical activity). The results indicated qualitative and quantitative changes in the interactions of the dyad after the implementation of the intervention program. The student began to use pictograms to communicate with the teacher in two of the three routines investigated. The frequency of AAC use was also observed in the teacher‟s repertoire, especially when the student failed to understand gestures and words. The teacher positively evaluated the intervention program

Contribuição para o estudo do embarque de uma rede neural artificial em field programmable gate array (FPGA)

This study shows the implementation and the embedding of an Artificial Neural Network (ANN) in hardware, or in a programmable device, as a field programmable gate array (FPGA). This work allowed the exploration of different implementations, described in VHDL, of multilayer perceptrons ANN. Due to the parallelism inherent to ANNs, there are disadvantages in software implementations due to the sequential nature of the Von Neumann architectures. As an alternative to this problem, there is a hardware implementation that allows to exploit all the parallelism implicit in this model. Currently, there is an increase in use of FPGAs as a platform to implement neural networks in hardware, exploiting the high processing power, low cost, ease of programming and ability to reconfigure the circuit, allowing the network to adapt to different applications. Given this context, the aim is to develop arrays of neural networks in hardware, a flexible architecture, in which it is possible to add or remove neurons, and mainly, modify the network topology, in order to enable a modular network of fixed-point arithmetic in a FPGA. Five synthesis of VHDL descriptions were produced: two for the neuron with one or two entrances, and three different architectures of ANN. The descriptions of the used architectures became very modular, easily allowing the increase or decrease of the number of neurons. As a result, some complete neural networks were implemented in FPGA, in fixed-point arithmetic, with a high-capacity parallel processing

Fractais e percolação na recuperação de Petróleo

The complex behavior of a wide variety of phenomena that are of interest to physicists, chemists, and engineers has been quantitatively characterized by using the ideas of fractal and multifractal distributions, which correspond in a unique way to the geometrical shape and dynamical properties of the systems under study. In this thesis we present the Space of Fractals and the methods of Hausdorff-Besicovitch, box-counting and Scaling to calculate the fractal dimension of a set. In this Thesis we investigate also percolation phenomena in multifractal objects that are built in a simple way. The central object of our analysis is a multifractal object that we call Qmf . In these objects the multifractality comes directly from the geometric tiling. We identify some differences between percolation in the proposed multifractals and in a regular lattice. There are basically two sources of these differences. The first is related to the coordination number, c, which changes along the multifractal. The second comes from the way the weight of each cell in the multifractal affects the percolation cluster. We use many samples of finite size lattices and draw the histogram of percolating lattices against site occupation probability p. Depending on a parameter, ρ, characterizing the multifractal and the lattice size, L, the histogram can have two peaks. We observe that the probability of occupation at the percolation threshold, pc, for the multifractal is lower than that for the square lattice. We compute the fractal dimension of the percolating cluster and the critical exponent β. Despite the topological differences, we find that the percolation in a multifractal support is in the same universality class as standard percolation. The area and the number of neighbors of the blocks of Qmf show a non-trivial behavior. A general view of the object Qmf shows an anisotropy. The value of pc is a function of ρ which is related to its anisotropy. We investigate the relation between pc and the average number of neighbors of the blocks as well as the anisotropy of Qmf. In this Thesis we study likewise the distribution of shortest paths in percolation systems at the percolation threshold in two dimensions (2D). We study paths from one given point to multiple other points. In oil recovery terminology, the given single point can be mapped to an injection well (injector) and the multiple other points to production wells (producers). In the previously standard case of one injection well and one production well separated by Euclidean distance r, the distribution of shortest paths l, P(l|r), shows a power-law behavior with exponent gl = 2.14 in 2D. Here we analyze the situation of one injector and an array A of producers. Symmetric arrays of producers lead to one peak in the distribution P(l|A), the probability that the shortest path between the injector and any of the producers is l, while the asymmetric configurations lead to several peaks in the distribution. We analyze configurations in which the injector is outside and inside the set of producers. The peak in P(l|A) for the symmetric arrays decays faster than for the standard case. For very long paths all the studied arrays exhibit a power-law behavior with exponent g ∼= gl.