964 resultados para Reforço de subleito


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Although there are a wide variety of additives that act in fresh state, to adjust the properties of cement, there is also a search by additions that improve the tenacity of the cement in the hardened state. This, in turn, can often be increased by inserting fibers, which act on the deflection of microcracks. This study aimed to use a microfiber glass wool (silica-based) as an additive reinforcing the cement matrix, improving the rupture tenacity, in order to prevent the propagation of microcracks in the cement sheath commonly found in oil wells submitted to high temperatures. The fibers were added at different concentrations, 2 to 5% (BWOC) and varied average sizes, grinding for 90 s, 180 s, 300 s, 600 s. The cement slurries were made with a density of 1,90 g/ cm3 (15,6 lb/gal), using Portland cement CPP- Special Class as the hydraulic binder and 40% silica flour. The characterization of the fiber was made by scanning electron microscopy (SEM), particle size by sieving, X-ray fluorescence (XRF), X-ray diffraction (XRD) and thermogravimetry (TG / DTG). Were performed technological tests set by the API (American Petroleum Institute) by rheology, stability, free water, compressive strength, as well as testing rupture energy, elastic modulus and permeability. The characterization results showed good thermal stability of the microfiber glass wool for application in oil wells submitted to steam injection and, also, that from the particle size data, it was possible to suggest that microfibers milled up to 300 s, are ideal to act as reinforcement to the cement slurries. The rheological parameters, there was committal of plastic viscosity when larger lengths were inserted of microfiber (F90). The values obtained by free water and stability were presented according to API. The mechanical properties, the incorporation of microfiber to the cement slurries gave better rupture tenacity, as compared to reference cement slurries. The values of compressive strength, elastic modulus and permeability have been maintained with respect to the reference cement slurries. Thus, cement slurries reinforced with microfiber glass wool can ensure good application for cementing oil wells submitted to steam injection, which requires control of microcracks, due to the thermal gradients

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Avaliação da eficácia de um programa de educação sobre o conhecimento relacionado à postura sentada de estudantes da 1ª série do ensino fundamental, na esfera estadual, particular e municipal, em Bauru. Foram avaliados (pré-teste) 71 alunos e depois aplicado um programa de educação sobre o tema, composto de aulas expositivas, técnicas de demonstração e feedback, associado a um programa de reforço ministrado por professoras treinadas e, finalmente, a reavaliação (pós-teste) dos conhecimentos dos participantes. Foi observado que: 1) no pré-teste ocorreu diferença significativa entre as escolas, sendo que a municipal apresentou menor número de erros do que a particular e a estadual; 2) o pós-teste mostrou que houve diferença significativa sendo que as escolas municipal e particular tiveram um menor número de erros em relação a estadual; 3) em todas as escolas houve predominância da situação de erro pré-teste maior que pós-teste. A escola estadual tem resposta mais freqüente que a particular quando há aumento de erro. Conclui-se que o programa se mostrou eficaz para aumentar os conhecimentos dos escolares a respeito da postura sentada.

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The study Escola e Gênero: representações de gênero na escola show us the social man made, starting of an analysis in the having fun time in the children´s life and how it´s an important aspect of the building childish universe simbolic. My analysis started in a children´s daily at school and how they noticed the play value od dominant society. Our propouse is think about the linking between ideology, representations and gender like the children´s knowledge in the school activities. The toy, an instrument which is noticed and exist in the funny activities, is full of cultural concepts of male and female parts. Your color, lines, functions and the way you manipulate is driven of gender cathegories. In the scool, the ideological concepts have it´s important way which is to domesticate the feelings, the desires; categorize and normalize them without be known by the educational employers. In the children´s education, the funny time is noticed by others ways and turned as important as others subjects. By the way it´s not noticed by the school, like another thing which isn´t a funny moment. And it´s exactly here in the school funny time, the school did your cultural power of separete the gender and your extencions, feed by the society, generaly, in favor of the man whose woman is your subordinate. This ways of analysis help the society and the school universe about the funny time e how they are important in the Man made life. And how the toys bring the concepts and addicted thinking, ideological which put the power in the stages, without equal, addicted feelings around the gender concepts. I read and used the theories of Kishimoto, Berger & luckmann, Brougère, Sousa Filho, Bourdieu, Badinter, Geertz, Grossi, Louro, Foucault, among others

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Cet étude est une recherche sur les significations imaginaires de la violence pratiquée par des jeunes délinquants ou à laquelle ils sont soumis, dans la condition de confinés chez le Centre Éducationnel CEDUC/PITIMBU, lieu où l investigation a été faite. Dans la mésure où le sujet de la violence se présente plein de manifestations, nous proposons ici une réflexion sur l imaginaire de la production théorique sur la question et en même temps nous nous proposons identifier jusqu à quel point les diverses visions scientifiques établient un savoir qui finit par limiter une conception plus complexe et profonde des réseaux de la violence. Le parcours théorique et méthodologique realisé nous a permis concluire que certaines interventions finissent par renforcer des situations limites vécues à l intèrieur du Centre par les jeunes déliquants. Parmi d autres aspects, nous traitons de l espace de l institution, leurs objectifs, routines, aussi bien que sur les principaux expressions de la violence qu apparaissent dans les récits des jeunes. Nous traitons de leurs origines socioculturelles, en signalant les milieux d oú ils viennent et leur vie quotidienne. Ainsi, nous traitons d analyser les éléments de la culture constituée, les valeurs, la « loi de plus fort », le pouvoir, le courage, la peur, l astuce, la sagesse et les rêves. Nous remarquons aussi la notion de « destin » qui renvoie à l idée que le crime et la mort sont inéluctables. Nous nous occupons de réfléchir sur le rôle de l institution dans le renforcement de la violence et dans la reproduction de valeurs sociales. Dans cet étude, nous utilisons l analyse des trajectoires de vie des jeunes délinquants pour comprendre la réalité de la violence à laquelle ils sont soumis

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Mediante a utilização da prova de soroaglutinação microscópica (SAM), foi pesquisada a indução de anticorpos contra leptospira em bovinos vacinados com uma bacterina polivalente comercial. Procurou-se avaliar a resposta sorológica homóloga frente a dois esquemas de vacinação. Os animais utilizados foram fêmeas adultas em produção leiteira oriundas de seis propriedades da região noroeste do Estado de São Paulo. Vinte animais de cada propriedade foram escolhidos após três exames sorológicos com 24 sorovares de leptospiras com intervalo de 20 dias, através de triagem sorológica com 24 antígenos de leptospiras. Os grupos foram constituídos de animais não reagentes (I, II e III) e animais reagentes (IV, V e VI). Posteriormente os animais foram subdivididos em grupos controle (I e IV), os que receberam somente uma dose de vacina (II e V) e que receberam duas uma doses de vacina com e dose de reforço após 30 dias (III e VI). Os animais foram monitorados por meio da SAM nos dias 0, 15, 30, 45 e 60 após a primeira aplicação da vacina. Os resultados obtidos revelaram que não houve diferença significativa (p>0,05) entre os animais vacinados e não vacinados. Não houve diferença significativa (p>0,05) nas respostas de títulos vacinais com relação ao perfil sorológico apresentados pelos animais. A vacinação com reforço apresentou melhor desempenho e a indução produção de aglutininas somente ocorreu contra os sorovares hardjo, wolffi, icterohaemorrhagiae e pomona. Há a necessidade de maiores estudos sobre o poder imunogênico da vacina utilizada no experimento.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Advocating education as a humanizing task, the humanizing function of literature and the importance of scientific education, this paper proposes linking Science and Literature in Science Teaching using two specific books of Monteiro Lobato in the final series of elementary school level. Adopting the action research methodology, an interdisciplinary approach, we used the books A Reforma da Natureza and Serões de Dona Benta in two classes (8th and 9th) at Escola Estadual Professor José Mamede, located in the town of Tibau do Sul, Rio Grande do Norte. The readings were performed in Portuguese Language s course and the scientific content were discussed in Science´s classrooms. The book A Reforma da Natureza permitted to approach issues related to the environment, while the use of Serões de Dona Benta showed particularly its effectiveness in questioning the concepts of matter, mass, weight and some questions about the Nature of Science (NOS). In general, the analysis of results shows that the readings of these two books permitted interaction and dialogicity in the classroom, as well as indicates the potential of these books in contextualing and questioning the scientific content contained in it. We advise, however, the need for the science teacher be aware of the conceptual mistakes present in literary works, avoiding erroneous learning and reinforcement of alternative conceptions

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Comprehending social representations of users relatives of Psychosocial Care Centers (CAPS) from Natal-RN, about their participation in the activities of these services, was the purpose of this study. The research instrument used was a semi-structured interview, led to 28 relatives of users of East and West CAPS II, East and North CAPS-ad, involved in the Relative Therapeutic Group, in Relative Meeting, in the Assembly of Users, Technicians and Relatives, according to the therapeutic schedule of each health services, between August to November 2007. Data obtained in family and users identification were characterized with the aid of charts and boards in absolute and/or percentage values. The discursive material from the guide from interviews was submitted to the informational resource ALCESTE (Analyse Lexicale par Contexte d'un Ensemble of Segments of Texte), and analyzed on the basis of the Theory of Social Representations and Central Nucleus Theory. Most of the relatives were women, married, aged over 50 years, who participated for more than two years in CAPS activities, and a coexistence of more than 11 years with the user. From the classification system of ALCESTE were selected categories, identified by: Category 1, Treatment Improvements and Expectations; Category 2, Living User Before and After; Category 3, Activities Relevance, Contradictions and Suggestions; Category 4, Guidelines -- Psychopharmacology and Medicalization; Category 5, Family Participation and Activities; and Category 6, Therapeutic Conditions Thanks, Tips and Vulnerability. The social representation of the family exists in the desire for change, identifying that we need to promote change by the continuity of therapeutic activities and overcome the detected inconsistencies, targeted by strengthening and by the stability of improvements in living and health conditions of users, experienced in CAPS treatment. The central nucleus had corresponded to positive changes in health and living conditions of users, and the peripheral elements were constituted by family conducts before and during treatment, and the expectations of changes in activities, especially in workshops. Despite this family participation be considered important, it still does not meet conditions to promote the inclusion of family, under an emancipating point of view, capable of causing in subject the hope for autonomy, initiative, individual and collective growths, a closer and active involvement in therapeutic activities, in workshops and discussions

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Exploratory descriptive study, with a quantitative approach and prospective data, performed in Pronto Socorro Clóvis Sarinho (PSCS), in Natal/RN, aiming to analyze care given by the nursing and medical staff to victims of violence attended to in an emergency hospital in Natal/RN; to identify care given by the nursing and medical staff as viewed by the victims; to compare data observed during the process of care with the victim s view on the care given by the nursing and medical staff; to identify the existing knowledge on violence and the process of caring for victims and its relation with prejudice; to identify obstacles and perspectives for prevention during the process of caring for victims in the emergency services. The population consisted of 97 physicians, 16 nurses, 75 nursing technicians and assistants and 365 victims of violence, with data collected from April to May 2009. Out of 188 professionals, 52.1% are female; 32% were aged 41 to 50; 99.5% had given care to a victim of violence; 90.4% reported to have given care to patients under custody; among these, 17.3% felt prejudice; 55.3% stated they don t provide different care for assaulted victims and assailants, however 44.7% stated they do; 86.7% feel their workplace is unsafe; 61.7% denied the existence of any obstacle and 38.3% reported the existence of obstacles; among these, 26.1% referred to inadequate facilities; 37.8% believe reinforcing security and professional training are the main solutions. Among the 365 researched violence victims, 82.2% were assaulted; male (69.6%); aged 18 to 24 (24.9%); hailing from the Greater Natal area (89.9%); on 19.7% the event happened on Saturday; during the night (48.8%); victim of physical assault (61.4%); produced by body force (27.7%); 24.4% were injured in the head and neck. 57% had used some drug, among which alcohol was predominant (75.5%). On 621 observations performed during the victim care process, when compared to the report of assaulted victims, there was a statistical difference, at 5% significance level, regarding reception, resistance from the professionals, questioning about the violent event, providing of guidance, interaction with the patient and the understanding of receiving proper care, and care resolution. In comparisons involving the observed and the assailant victims reports, there was a statistical difference regarding the resence of resistance from the professionals, performance of necessary procedures and the nteraction with the patient and the understanding of receiving proper care and 58.1% reported the nursing team was the one that provided the best care. We conclude that professionals had lready given care to assailant patients, acknowledge the importance of knowing how the vent took place and acquired this preparation during their practice. The most often referred bstacles that hinder assistance were: inadequate facilities, material deficit and lack of rofessional preparation. As solutions for these problems, they cited the reinforcement of ecurity and professional training

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This study discusses the use of information technologies for knowledge management in networks of franchises in the Rio Grande do Norte/Brazil, whose management and operation are complex activities, characterized by the geographic spread of their network unities, creating barriers to communication and information sharing between franchisors, franchisees and final customers. In view of this, the following hypotheses were formulated: the knowledge management can be a positive alternative for improving communication between units; and information technology can eliminate many problems related mainly to capture and share knowledge. In general, it aims to investigate, in qualitative and quantitative aspects, how information technology can support knowledge management in networks of franchises. Specifically purposes to register the existence of managerial practices related to knowledge management in enterprises at the franchising sector; to verify whether they have the technological resources with the potential to facilitate the sharing of information; to identify what are the technologies of information and communication used in the organizational environment; and suggest measures that will facilitate the process of organizational learning, using information technology and communication as tools. It concludes that knowledge management becomes a positive alternative, especially in strengthening of bonds of communication and sharing of knowledge between the franchises. In this regard, information technology must provide all the services of the corporation to facilitate communication between franchisor and franchisee, through a single and integrated system. However, they still show unsuitable for more sophisticated technology platforms

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Techniques of optimization known as metaheuristics have achieved success in the resolution of many problems classified as NP-Hard. These methods use non deterministic approaches that reach very good solutions which, however, don t guarantee the determination of the global optimum. Beyond the inherent difficulties related to the complexity that characterizes the optimization problems, the metaheuristics still face the dilemma of xploration/exploitation, which consists of choosing between a greedy search and a wider exploration of the solution space. A way to guide such algorithms during the searching of better solutions is supplying them with more knowledge of the problem through the use of a intelligent agent, able to recognize promising regions and also identify when they should diversify the direction of the search. This way, this work proposes the use of Reinforcement Learning technique - Q-learning Algorithm - as exploration/exploitation strategy for the metaheuristics GRASP (Greedy Randomized Adaptive Search Procedure) and Genetic Algorithm. The GRASP metaheuristic uses Q-learning instead of the traditional greedy-random algorithm in the construction phase. This replacement has the purpose of improving the quality of the initial solutions that are used in the local search phase of the GRASP, and also provides for the metaheuristic an adaptive memory mechanism that allows the reuse of good previous decisions and also avoids the repetition of bad decisions. In the Genetic Algorithm, the Q-learning algorithm was used to generate an initial population of high fitness, and after a determined number of generations, where the rate of diversity of the population is less than a certain limit L, it also was applied to supply one of the parents to be used in the genetic crossover operator. Another significant change in the hybrid genetic algorithm is the proposal of a mutually interactive cooperation process between the genetic operators and the Q-learning algorithm. In this interactive/cooperative process, the Q-learning algorithm receives an additional update in the matrix of Q-values based on the current best solution of the Genetic Algorithm. The computational experiments presented in this thesis compares the results obtained with the implementation of traditional versions of GRASP metaheuristic and Genetic Algorithm, with those obtained using the proposed hybrid methods. Both algorithms had been applied successfully to the symmetrical Traveling Salesman Problem, which was modeled as a Markov decision process

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In multi-robot systems, both control architecture and work strategy represent a challenge for researchers. It is important to have a robust architecture that can be easily adapted to requirement changes. It is also important that work strategy allows robots to complete tasks efficiently, considering that robots interact directly in environments with humans. In this context, this work explores two approaches for robot soccer team coordination for cooperative tasks development. Both approaches are based on a combination of imitation learning and reinforcement learning. Thus, in the first approach was developed a control architecture, a fuzzy inference engine for recognizing situations in robot soccer games, a software for narration of robot soccer games based on the inference engine and the implementation of learning by imitation from observation and analysis of others robotic teams. Moreover, state abstraction was efficiently implemented in reinforcement learning applied to the robot soccer standard problem. Finally, reinforcement learning was implemented in a form where actions are explored only in some states (for example, states where an specialist robot system used them) differently to the traditional form, where actions have to be tested in all states. In the second approach reinforcement learning was implemented with function approximation, for which an algorithm called RBF-Sarsa($lambda$) was created. In both approaches batch reinforcement learning algorithms were implemented and imitation learning was used as a seed for reinforcement learning. Moreover, learning from robotic teams controlled by humans was explored. The proposal in this work had revealed efficient in the robot soccer standard problem and, when implemented in other robotics systems, they will allow that these robotics systems can efficiently and effectively develop assigned tasks. These approaches will give high adaptation capabilities to requirements and environment changes.

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Geopolymers are cementing materials that depict a number of advantages compared to Portland cement. Contrary to the latter, geopolymers are synthesized at room temperature, thus significantly reducing the emission of CO2 to the atmosphere. Moreover, the composition and synthesis reactions can be tailored to adjust the setting time of the material as well as its compressive mechanical strength. It is then possible to produce geopolymeric cements with short setting times and high compressive strength, although relatively brittle. The objective of the present study was to produce and characterize composite materials by reinforcing fastsetting geopolymeric matrixes with polypropylene geosynthetics (geomats and geotextiles) in an attempt to improve the toughness and tensile strength of the cementing material. Geosynthetics have been increasingly used to reinforce engineering structures, providing higher strength and better toughness. In particular, polypropylene nonwoven and geomats depict other attractive properties such as low density, durability, impact absorption and resistance to abrasion. Fast-setting geopolymers were then synthesized and reinforced with polypropylene nonwoven and geomats. The mechanical strength of the materials, reinforced or not, was characterized. The results showed that relatively short setting times and adequate flowing behavior were achieved by adjusting the composition of the geopolymer. In addition, it is possible to improve the fracture resistance of geopolymeric cements by adding polypropylene geosynthetics. The best results were achieved by reinforcing geopolymer with polypropylene TNT

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The advantage in using vegetable fibres in place of synthetic fibres such as glass fibre, for reinforcements in composites are: biodegradability, low cost, low density, good tenacity, good thermal properties, low energy content and reduced use of instruments for its treatment or processing. Even though, problems related to low mechanical performance of some of the natural fibres, has caused difficulty in their direct application in structural elements. The use of alternative materials like hybrid composites has been encouraged, thus trying to better the structural performance of the composites with natural fibres. This work presents a comparative study of the strength and stiffness of hybrid composites with orthopthalic polyester matrix reinforced with E-fibre glass, jute and curauá. The experimental part includes uniaxial tension and three point bending tests to determine the mechanical properties of the final product. The hybrid composite was manufactured in a local industry and was in the form of laminates. All the samples were projected to withstand the possible structural applications as reservoirs and pipes. CH (laminated hybrid composite with glass and curauá fibres). The results obtained show clearly the influence of the hybridization in all the types tested and indicate a good mechanical performance of the composite with glass/curauá fibres in relation to the composite with glass fibres. Aspects in relation to the interfaces glass/curauá composites besides the fracture characteristics for all loading types were also analysed

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The advantages of the use of vegetable fibers on the synthetic fibers, such as glass fibers, in the reinforcements in composites are: low cost, low density, good tenacity, good thermal properties and reduced use of instruments for their treatment or processing. However, problems related to poor performance of some mechanical natural fibers, have hindered its direct use in structural elements. In this sense, the emergence of alternative materials such as hybrids composites, involving natural and synthetic fibers, has been encouraged by seeking to improve the performance of structural composites based only on natural fibers. The differences between the physical, chemical and mechanical properties of these fibers, especially facing the adverse environmental conditions such as the presence of moisture and ultraviolet radiation, is also becoming a concern in the final response of these composites. This piece of research presents a comparative study of the strength and stiffness between two composite, both of ortoftalic polyester matrix, one reinforced with fibers of glass-E (CV) and other hybrid reinforced with natural fibers of curauá and fiberglass-E (CH). All the comparative study is based on the influence of exposure to UV rays and steam heated water in composites, simulating the aging environment. The conditions for the tests are accelerated through the use of the aging chamber. The composites will be evaluated through tests of uniaxial static mechanical traction and bending on three points. The composite of glass fiber and hybrid manufacturing industry are using the rolling manual (hand lay-up) and have been developed in the form of composites. All were designed to meet possible structural applications such as tanks and pipes. The reinforcements used in composites were in the forms of short fiber glass-E quilts (450g/m2 - 5cm) of continuous wires and fuses (whose title was of 0.9 dtex) for the curauá fibers. The results clearly show the influence of aging on the environmental mechanical performance of the composite CV and CH. The issues concerning the final characteristics of the fracture for all types of cargoes studied were also analyzed