O ensino médio no Brasil: trajetória e perspectivas de uma organização politécnica entre educação e trabalho

The objective of this article is to present an abbreviation analysis and interpretation of the path of the medium teaching in Brazil, from where the idea of the relationship emerges between education and work, among theory and practice, and its organization in the molds of the polytechnical education, this last one that had guided the preliminary proposal for the medium teaching presented by Dermeval Saviani, in 1988. In that sense, subjects were approached on education and work. Finally, they were made brief considerations on the theme in the educational context for besides the capital

Prejuízos educacionais: a semiformação intensificada

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tratamento de modificação de eutético da liga AA356

Alloy Al-7%Si-0,3Mg (AA356), having an excellent combination of properties such as low solidification shrinkage and good fluidity, good weldability, high wear resistance, high strength to weight particularly in the automotive and aerospace engineering. The refinement of the structure aluminum silicon eutectic alloy is a fairly common practice in the casting, through the treatment knows as modification. You can get the modification for the addition of chemicals and rare earths, these have the ability to modify the structure of the eutectic, but only sodium and strontium produce a strong action modifier when used in low concentrations. The modifying effect of silicon grain turns into a fibrous form branched and enveloped by the metal matrix in the form of a composite structure that has the highest limit of tensile strength, ductility and machinability. This work will be obtained AA356 alloy ingots using two different types of molds: metal mold and sand mold. Macrographs will be made in ingots obtained for observation of the macrostructures obtained in both types of ingots. Will be sampled at strategic locations of the ingots to correlate microstructure and cooling rate. The results showed that the material of the ingot has a strong influence on the resulting micro-andmacrostructure

Preparação de substratos de carbeto de silício para fins aeroespaciais

This conclusion thesis has the objective of produce substrates of Silicon Carbide from the powder of SiC for aerospace use. The powder of SiC was pressed in cylindrical form by the process called “wet way”. For the inicial pressing process was used a uniaxial squeezer and after that was used a isostatic squeezer, after that the samples were synthesized. The next step was the machining and polishing to improve the features of the surface of the sample. Then the roughness was measured, as also the Arquimedes method and optical microscopy and scanning eletron microscopy. Some innovations were done, in one of the lots little vacancys were done with organic material or silicon to reduce the weight of the sample; and the other innovation were the use of a slip film of SiC on the surface of the sample, that were after synthesized with LASER to reduce the roughness, in this samples the roughness were reduce in 50 % if compared with the other samples

Um estudo sobre a preparação metalográfica da liga de aluminio AA7075-T6

The increasing technological innovation and demand for materials with better properties boosts research into new materials and new alloys. To do so, aluminum alloys are being developed, among them the AA7075-T6, having many applications in aerospace and military industries, machinery and equipment, molds for plastic injection and structures. To study and understand the properties, characteristics and especially the microstructure of the material, the metallographic preparation is essential. This paper presents new methodologies to achieve the metallography of samples of scrap alloy AA7075-T6, with emphasis on methods of polishing. For the five samples, the best results were those with specific grinding, the samples only going down on the sander. For polishing, the most effective method so far has been using the polishing cloth 16.3, of ATM enterprise, solution of diamond 3 μm, solution of diamond 1 μm, and colloidal solution of OP-S. For the etching, the reactive agent used was phosphoric acid (H3PO4) 85% P.A., as 90% in the proportion of distilled water to 10% acid. The best results were obtained in the attacks of 300 and 240 seconds, revealing the grain boundaries in most areas. Methodologies need more studies and more tests, but the results have proved to be satisfactory

Análise comparativa entre sistemas de resfriamento de injeção de plástico

This study aims to prove the economic feasibility of the installation of mechanical compression chillers on plastic injection molding machines in order to reduce the production cycle time of toothbrush cables in a specific case study. This evidence was confirmed by the comparative analysis of the system replaced and the new system installed. The old system had only one closed loop cooling tower which pumped chilled water to the injection molds, and the new system has the same tower sending cold water to the condensers of individual chillers installed on each injection machine. We conducted an analysis of energy efficiency in each system, showing that in terms of thermal efficiency virtually nothing has changed, but in terms of electricity demand the new system consumes 60.3 kW more. We conducted an analysis of machine productivity for both systems, showing a much higher productivity of the new system due to reduced cycle times caused by the presence of chillers and their greater cooling capacities. Equipped with data such as electricity rates, increases in operating costs and initial investments, the increase in consumption and demand of electricity plus the cycle time reduction were also calculated over so the simple payback 1 year and 2 months was reached

Estudo da eficiência de reforços estruturais em vigas de concreto armado com o uso de chapas de aço coladas com resina epóxi: uma análise qualitativa

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

Estudo do efeito do modificador Al-Sr no tratamento de modificação do eutético da liga AA356

The AA356 alloy is an alloy widely used in the automotive industry and aerospace due to its excellent mechanical properties. Refining the structure of eutectic silicon aluminum alloys is a fairly common practice in the foundry through treatment known as modification. This can be achieved by modifying agent adding chemicals such as contained in groups I and IIa of the periodic table and rare earths (europium, céreioi, praseodymium, neodymium, etc.). Has the ability to modify the structure of the eutectic, but only sodium and strontium produce an action modifier strong when used in low concentrations. The modifying effect of the shafts turn silicon into a fibrous form and branched surrounded by metallic matrix in the form of a composite structure that has the highest limit of tensile strength, ductility and machinability. In this work will be obtained ingots with and without the modifier type Al-10% Sr, made in sand molds and are generated and analyzed cooling curves and also the study of the macrostructure and microstructure of the solidified material. It was found that by adding the Al-Sr made shorten the solidification time and lower the grain size

O jazz e a mundialização: processos culturais e consumo musical no século XX

Jazz brings to the surface discussions about globalization and its unfolding. The development of such music style allows a reflection about the processes that influence 20th century culture, thus enabling a closer look into debates that involve cultural industrialization and standardization in such context. Horkheimer‟s and Adorno‟s work deal with this theme, considering culture as something standardized, a result of the process that fits into the industrial production mold. Morin goes further in this discussion, suggesting the emergence of a mass culture as a third culture. Later, Latin-American authors Ortiz and Canclini bring up new tones and approaches to the globalization through culture theme

O mercado editorial na formação dos professores da educação básica: levantamento e caracterização de revistas pedagógicas (1996-210)

A pesquisa tem por foco o mercado editorial voltado para a formação dos professores da educação básica, com ênfase para as revistas pedagógicas com periodicidade regular em circulação na região Sudeste do país. Objetivou-se reconhecer e caracterizar manifestações desse mercado a partir da análise da materialidade das revistas, buscando encontrar também representações sobre os professores e sua profissão. O trabalho foi realizado sob uma abordagem qualitativa, nos moldes da pesquisa documental. Em um primeiro momento, realizou-se a identificação de quais são as revistas pedagógicas disponíveis no mercado e a que tipo de profissional elas se destinam, partindo de levantamento de materiais presentes em bancas de jornal, livrarias, bibliotecas e também em sites especializados. O segundo momento caracteriza-se pela análise e comparação da materialidade das revistas. Trata-se de um Trabalho de Conclusão de Curso que teve apoio financeiro pelo Programa Institucional de Bolsas de Iniciação Científica da Pró-Reitoria (PROPE) de Pesquisa da UNESP (PIBIC/Reitoria). É parte do projeto “Mercado de formação docente: constituição, funcionamento, possibilidades e limites”, financiado pelo CNPq, que por sua vez integra o Projeto Temático FAPESP “Programas Especiais de Formação de Professores, educação a distância e escolarização: pesquisas sobre novos modelos de formação em serviço

Análise macro e micrográfica da liga AA-356 conforme a taxa de resfriamento

The present work aims to study the characteristics of the alloy Al - 7 % Si - 0 , 3Mg ( AA356 ) , more specifically characterize the macrostructure and microstructure and mechanical properties of the alloy ingots AA356 obtained in metal molds and sand molds for power studying the structures through the difference of cooling rates . This alloy is explained by the fact of referring league has excellent combination of properties such as low solidification shrinkage and good fluidity, good weldability , high wear resistance , high strength to weight ratio, has wide application in general engineering , and particularly in the automotive and aerospace engineering . In this work we will verify this difference in properties through two different cooling rates . We monitor the solid solidification temperatures by thermocouples building with them the cooling curve as a tool that will aid us to evaluate the effectiveness of the grain refining because it achieved with some important properties of the alloy as the latent heat of solidification fraction the liquid and solid temperatures, the total solidification time, and identify the presence of inoculants for grain refinement. Thermal analysis will be supported by the study of graphic software “Origin “will be achieved where the cooling curve and its first derivative that is the cooling rate. Made thermal analysis, analysis will be made in macrographs ingots obtained for observation of macrostructures obtained in both types of ingots and also analysis of micrographs where sampling will occur in strategic positions ingots to correlate with the microstructure. Finally will be collecting data from Brinell hardness of ingots and so then correlating the properties of their respective ingots with cooling rate. We found that obtained with cast metal ingots showed superior properties to the ingots obtained with sand mold

Saber docente e acadêmico: possibilidade para uma formação coerente

O presente trabalho apresenta a experiência vivenciada, no ambiente universitário, de um grupo de alunos da Pedagogia que se envolveram no projeto de extensão “Grupo de Formação: Diálogo e Alteridade” no ano de 2010, oferecido na UNESP de Rio Claro. O objetivo geral do trabalho é compreender, a partir de análise de documentos, os processos formativos desencadeados nesses alunos, no contexto desse projeto e entender as contribuições do mesmo para a formação inicial. Este trabalho discute, a partir de uma pesquisa bibliográfica, os conceitos de saberes docentes, diálogo e trabalho coletivo. Os dados serão obtidos a partir da leitura de uma série de documentos: caderno de registro do grupo, caderno de registro da pesquisadora e as avaliações elaboradas pelos participantes do primeiro e do segundo semestre do ano de 2010. A partir da discussão dos textos e das trocas das experiências desses alunos (ao participar de um projeto de pesquisa na escola e de um curso de extensão para professores da rede municipal de ensino), o projeto de extensão, promovia em nós, universitários, um processo formativo diferente dos moldes convencionais. Isto repercutiu e permitiu uma complementação da formação acadêmica justamente por estar vinculada às experiências advindas da prática docente, e, com isso, uma visão diferenciada e mais próxima da realidade escolar. Busco, nesse contexto, analisar os saberes construídos por esses estudantes ao longo do projeto. Enfatizo as mudanças e questionamentos que foram necessários para que escola e universidade deixassem de ser meros espaços físicos e que começassem a ser parte de uma relação que permitiu a modificação nos aspectos formativos desses estudantes

Caracterização estrutural da Liga Al-1% Si

The aim of this study is to characterize the macrostructure and microstructure of Al - 1%Si alloy obtained in sand and metallic molds. Aluminium has good mechanical properties, but adding silicon, even in small quantities, can change the microstructure and improves mechanical behavior. Workpieces were castings in metallic and sand molds and one can see a difference in their cooling curve, macroscopic and microscopic structures. The sand mold casting has lower cooling rate and so its grains are larger. Due to the lower concentration of grain boundary, the hardness is lower compared to that found in metallic molds, which has smaller grains and a higher hardness. Therefore, it can be concluded that the cooling rate and alloying elements affect the final microstructure of the workpiece

Análise da curva de resfriamento da liga de alumínio AA 356

It is very important to study the macrostructure of a material in the crude state of solidification due to influence the mechanical properties, as well as the study of their cooling curve. In the present work was to study the alloy AA 356, its macrostructure and its cooling curve. The material was cast in two different molds, a sand and other metallic. In this paper we study the differences in its macrostructure and its cooling curves. In macrostructure can observe the absence of the three zones of solidification and the presence of large pores because of moisture in the sand. In the sample taken from the metal mold can observe the three zones of solidification: a coquilhada, columnar and equiaxed

Jogo Mega-Duque: uma proposta para o ensino de probabilidade

Pós-graduação em Matemática em Rede Nacional - IBILCE