957 resultados para Reforço


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In civil engineering, a structure is the whole sustainment of a construction and, thus, it is important that it remains intact throughout its lifetime. An engineering construction must last for decades without losing its functionality. However its purpose may be altered and several times the original structure does not meet the new needs of use. Still, in new buildings, the functionality is altered due to possible flaws in execution and the structure, invariably does not reach the desired solicitation needs. In cases like this, the commonly adopted solutions are, basically, the demolishment followed by the reconstruction of the desired mold or the structural reinforcement. This second option, for long years, has not been put to practice due to certain factors such as the high costs for its implantation, use of inadequate reinforcement execution techniques, and the culture of people involved in the area regarding its use and, in this case, the option would always be the reconstruction. Thoughtout the years, some techniques were developed to allow the execution of structural reinforcements with low costs and in efficient ways. An interesting, fast, efficient and economical technique is the structural reinforcement through metal sheets put together with epoxy resin that can be applied in beams, slabs and pillars. In the present work the different behavior of beams reinforced with this technique. Steel is a very recommended material for these reinforcements due to its characteristics related to traction, compression and the effectiveness of the technique related to its cost. For the attachment the epoxy resin is recommended, since it allows the joining of two materials, in this case, steel and concrete. The efficiency of this union is so considerably high that it rarely produces any flaws in adherence and, normally, when it happens it is due to problems in the execution process, not in the union of materials

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This work is the production of two types of particle boards reconstructed MDP (Medium Density Particleboard), the first with the addition, in the inner layer of particles of impregnated paper, the ratios of 0%, 1%, 5% and 20 %. In the second type of panel MDP was inserted with blades of bamboo species Dendrocalumus giganteus as coatings and structural reinforcement. The MDP panel, used as a basis for both cases has the composition of three layers, two external particles with smaller particle size and an inner layer composed of particles of larger particle sizes. Assays were performed based on physical and mechanical NBR 14.810/2006 for the determination of the board density, thickness swelling, water absorption, moisture content, bending, tension parallel and perpendicular, and testing of particle sizes of the particles did not exists in standard references. The results were analyzed and compared the results of the commercial boards made from 100% eucalyptus, based on the limits specified by the ABNT NBR 14.810/2006. The values of the tests showed similar results indicating normative specifications in a positive way, the possibility of production of MDP with the use of waste paper impregnated. As for the panel with bamboo blades, the tests showed a mechanical performance far superior to MDP market, explaining the study and possible implementation of the bamboo for use where the MDP will suffer greater mechanical stress, such as doors, tops and benches tables

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A antecipação constitui uma capacidade de extrema importância à evolução dos vertebrados, pois, ao permitir a geração de previsões e a orientação atencional para estímulos pendentes, possibilitou interpretações mais refinadas do meio, além de uma preparação para a ocorrência de estímulos críticos, aumentando as chances de sobrevivência daqueles que a possuem. O presente trabalho visou avaliar a habilidade de gerar comportamento antecipatório, por meio do teste de extrapolação a partir de padrões seriais de estímulos. Ratos da linhagem Wistar, machos, foram treinados a correr em uma pista reta, ao longo de 22 dias, para obter reforço ao final de cada uma de 4 tentativas sucessivas. Os sujeitos, organizados em dois grupos, foram expostos a uma sequência de quantidades de reforço envolvendo 14, 7, 3 e 1 sementes de girassol (Grupo Monotônico) ou 14, 3, 7 e 1 sementes de girassol (Grupo Não-Monotônico). No 23° dia do experimento uma quinta tentativa, nunca experienciada antes, portanto cuja quantidade de sementes não era conhecida, mas passível de extrapolação a partir do padrão serial, foi adicionada à sessão. Os resultados mostraram que os animais expostos ao padrão monotônico exibiram, na quinta tentativa, substancial aumento do tempo de corrida, como se esperassem uma quantidade de sementes menor do que a experimentada na tentativa anterior. Em contraste, os animais expostos ao padrão não-monotônico exibiram, na quinta tentativa, tempos de corrida relativamente baixos, indicando que esses animais geraram uma expectativa de obtenção de maior quantidade de sementes em relação à tentativa anterior. No conjunto, esses resultados indicam que ratos são capazes de extrapolar a partir de padrões seriais de estímulos, mostrando que esses animais são capazes de gerar previsões sobre condições ambientais que estão por vir, com base no registro de regularidades passadas mantidas na memória e na ...

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In this work polystyrene composites reinforced with recycled sisal fibers were processed, in order to apply in the manufacture of printed circuit boards. A thermoplastic matrix of recycled polystyrene was used, this material came from waste expanded polystyrene (EPS) used in appliance's packages. Composites were prepared with 15% and 25% of sisal fibers. To obtain the composites, wasted EPS and natural sisal fibers were chosen, to encourage recycling and reuse of household waste and also the use of renewable resources. The composites were analyzed by standard tensile and flexural test, in order to verify the mechanical properties of the material. The characterization of the composite was done by scanning electron microscopy (SEM) , thermogravimetry (TGA / DTG) , differential scanning calorimetry (DSC) and dielectric analysis . The analysis of the results showed that the percentage of fibers in the composite influences directly the thermal and mechanical properties. Plates with a lower percentage of fibers showed superior properties at a higher percentage. The composite material obtained is easy to process and it's use is feasible for the confection of printed circuit boards, considering it's mechanical, thermal and insulative properties

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The experiences lived in the Read and Write Program (Programa Ler e Escrever), through the scholarship project Public School and University at literacy (Escola Pública e Universidade na alfabetização), were the starting point for the preparation of this research. From this observations obtained in the classroom, it was noticed gaps present in the process of teaching-learning in the system imposed by the state government of Sao Paulo, preponderant factors to understand how and when children learn. This way, was noted that only one literacy proposal to be adopted by all schools revealed not being efective to meet different contexts, also disregards the individuality of each student. Thus, we applied the Paulo Freire's Method with children from Second year (Former First series) adapted in a playful way, during reinforcement classes at state shcool “Torquato Minhoto”, located in Bauru/SP. Sought to promote, properly, the comprehension of the language code and the development of learning in reading and writing. This manner, some barriers prevented a more thorough job covering a wider range of studantes over an extended period, however, the results were generally positives about the startup of literacy

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In order to study resin distribution and homogeneity of composite laminates manufactured by RTM, it was used CYCOM 890 monolithic toughened epoxy as a matrix with two different configurations of intermediated modulus (IM) carbon fibers: Satin Weave (5HS) and non crimp fabric (NCF). The injection parameters were defined based on Thermo Gravimetric Analysis (TG), Differential Scanning Calorimetry (DSC) and rheological analysis. After processing the material, the resin/fiber impregnation was studied using ultrasonic test, Thermo Gravimetric Analysis, Differential Scanning Calorimetry, Dynamic Mechanical Analysis (DMA) and flexural tests. Therefore, it was able to observe an internal residual stress during the cooling process in both laminates, higher in the composite using NCF fabric due to the lack of symmetry, although a good proportion of fiber/matrix has been verified by the lower values of flexural modulus deviation. The DMA enabled the visualization of glass transition and its association with the inter and intra molecular interaction and movement, in which the NCF composite presented better permeability due to the lowest temperature of glass transition, when compared to the Satin Weave composite

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As a more extensive issue, this paper deals with the polysemy attested in all Romance languages between interrogative pronouns and subordination markers in complex sentences. It investigates, specifically, the behavior of objective complement clauses introduced by “como” (“how”) in constructions in which they occur as equivalent to the meaning of prototypical declarative complement clause introduced by the conjunction “que” (“that”). It analyzes complement clauses introduced by “como” and “que” occurring in representative Portuguese texts from the thirteenth to the twentieth centuries. The results of the comparative analysis between the two forms of clausal complement show that in archaic Portuguese “como” was used primarily to introduce complement clauses of factive verbs. When the complement clause is introduced by “como”, the content that is presupposed as true due to the meaning of matrix verb has reinforced this factuality. In the passage from the archaic to the modern period, there was a drastic decrease in the frequency of occurrences of complement clauses with “como”, which are replaced by the form of completive introduced by the conjunction “que” in the context of factual constructions. In contemporary Portuguese, this replacement is fully established. Complement clauses with “como” remain rare and limited to specific contexts in which “como” maintains its reinforcement function of factual meaning.

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The proposal of this work is based on the elaboration of didactic sequences from fairy tales, for students of Elementary School, during reinforcement classes of Portuguese language. It is deemed appropriate to use this genre, because it gives to the child and to the adolescents a pleasurable reading, approaching them of playful situations. As a main goal of this work, this research aimed the preparation of didactic sequences using fairy tales in the classroom, as well as encouraging the reading for these students. The intention was also the internalization of the narratives and the messages conveyed by them, associating them to everyday situations. We used the deductive method, in which we initially organized the approach in the classroom and the teaching sequences from theoretical assumptions and materials already designed

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Due to growing concerns for reducing environmental damage caused by the use of non-renewable raw materials, there is a growing demand for research related to aggregate technology with environmental preservation. Thus, the use of non-renewable materials and less aggressive materials has been gaining attention. About composite materials, the exchange of synthetic fibers by natural fibers, especially vegetable fiber as reinforcement, has been increasing, due to its physical-chemical properties such as mechanical strength, nontoxic, low cost, low density, processing flexibility, non-abrasive to the process equipment, requiring simple surface treatments, etc. This objective was to process composites reinforced with long fibers of sapegrass in epoxy matrix and characterize the composites through mechanical tests. Three groups of composites were prepared according to the treatment received by the reinforcement: without treatment, alkali treatment at concentration of 5% w/v and alkali treatment at 10% w/v concentration. The materials were analyzed by tensile and flexural, and tests also optical microscopy and scanning electron microscopy (SEM). The results were statistically analyzed. As the main result, the alkali treatment of 5% in the sapegrass fibers increases the tensile and flexural strength, as a consequence of the improve adhesion between matrix and reinforcement

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Pós-graduação em Engenharia Mecânica - FEG

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Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

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The presented article discuss theoretical context and the practical impact reported in the bibliography about Continued Progression at São Paulo State schools. Such proceeding, oriented through Law of Basic Guidelines, LBG, from 1996, previses a restructuring in the Basic Education at the schools, primarily with respect to evaluations. Grades are replaced for cycles and reprobation only can happen if the student exceeds the limit of stated absences or for lowered acting at final of each cycle. The impact of educational public policy drafted through Continued Progression provoke transformations that need more attention, indicating a path of reflection turned to structural conditions in order that school offers the required reinforcement to students and assure quality education. It’s primordial understand, therefore, the endogenous and exogenous factors that leaded to adoption of such proceeding in the São Paulo State.

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This introductory text to the 40th Issue of "Pensamiento Propio" refers to the diversity in the search to expand and deepen democracy in the continent. Even after a decade of left-wing parties who prioritized implementing high-impact policies on social inequality which characterizes Latin America, the democratic deficit persists, both in the context of local and national governments and of the multilateral organizations of the hemisphere. Reflecting on the participation of civil society in the control of governments and the State in the past few decades is an absolute necessity for those who acknowledge the need to strengthen our political citizenship.

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Due to mechanical and aesthetic improvement properties, continuous fiber-reinforced composites have been developed to replace the metal framework in fixed partial dentures becoming an interesting alternative to conventional treatments. A male patient, 57 years old, attended at Fixed Partial Denture Clinic of Araraquara Dental School - UNESP, complaining about upper right first molar absence. After clinical examination, it was observed: upper right second molar with amalgam restoration and periodontal bone reduction and upper right second premolar unsatisfactory treated. Following the clinical conditions and the patient expectations, it was decided to use a fiber-reinforced composite resin to make a three-element fixed bridge. The patient showed full satisfaction with the aesthetic and functional results. The case has been followed up for 60 months.