Desenvolvimento de um núcleo versátil e integrado de ferramentas CAD/CAE para a modelagem e simulação de peças mecânicas

Currently there is still a high demand for quality control in manufacturing processes of mechanical parts. This keeps alive the need for the inspection activity of final products ranging from dimensional analysis to chemical composition of products. Usually this task may be done through various nondestructive and destructive methods that ensure the integrity of the parts. The result generated by these modern inspection tools ends up not being able to geometrically define the real damage and, therefore, cannot be properly displayed on a computing environment screen. Virtual 3D visualization may help identify damage that would hardly be detected by any other methods. One may find some commercial softwares that seek to address the stages of a design and simulation of mechanical parts in order to predict possible damages trying to diminish potential undesirable events. However, the challenge of developing softwares capable of integrating the various design activities, product inspection, results of non-destructive testing as well as the simulation of damage still needs the attention of researchers. This was the motivation to conduct a methodological study for implementation of a versatile CAD/CAE computer kernel capable of helping programmers in developing softwares applied to the activities of design and simulation of mechanics parts under stress. In this research it is presented interesting results obtained from the use of the developed kernel showing that it was successfully applied to case studies of design including parts presenting specific geometries, namely: mechanical prostheses, heat exchangers and piping of oil and gas. Finally, the conclusions regarding the experience of merging CAD and CAE theories to develop the kernel, so as to result in a tool adaptable to various applications of the metalworking industry are presented

Desenvolvimento de têxteis técnicos para reforço de compósitos poliméricos

Materials denominated technical textiles can be defined as structures designed and developed with function to fulfill specific functional requirements of various industrial sectors as are the cases of the automotive and aerospace industries. In this aspect the technical textiles are distinguished from conventional textile materials, in which the aesthetic and of comfort needs are of primordial importance. Based on these considerations, the subject of this dissertation was established having as its main focus the study of development of textile structures from aramid and glass fibers and acting in order to develop the manufacture of composite materials that combine properties of two different structures, manufactured in an identical operation, where each structure contributes to improving the properties of the resulting composite material. Therefore were created in laboratory scale, textile structures with low weight and different composition: aramid (100%), glass (100%) and aramid /glass (65/35%), in order to use them as a reinforcing element in composite materials with polyester matrix. These composites were tested in tension and its fracture surface, evaluated by MEV. Based on the analysis of mechanical properties of the developed composites, the efficiency of the structures prepared as reinforcing element were testified by reason of that the resistance values of the composites are far superior to the polyester matrix. It was also observed that hybridization in tissue structure was efficient, since the best results obtained were for hybrid composites, where strength to the rupture was similar to the steel 1020, reaching values on the order of 340 MPa

Desenvolvimento e caracterização de soluções ternárias água-glicerol-propilenoglicol como fluido refrigerante secundário

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Desenvolvimento de perfis aerodinâmicos a partir de suas características utilizando redes neurais artificiais

One of the current major concerns in engineering is the development of aircrafts that have low power consumption and high performance. So, airfoils that have a high value of Lift Coefficient and a low value for the Drag Coefficient, generating a High-Efficiency airfoil are studied and designed. When the value of the Efficiency increases, the aircraft s fuel consumption decreases, thus improving its performance. Therefore, this work aims to develop a tool for designing of airfoils from desired characteristics, as Lift and Drag coefficients and the maximum Efficiency, using an algorithm based on an Artificial Neural Network (ANN). For this, it was initially collected an aerodynamic characteristics database, with a total of 300 airfoils, from the software XFoil. Then, through the software MATLAB, several network architectures were trained, between modular and hierarchical, using the Back-propagation algorithm and the Momentum rule. For data analysis, was used the technique of cross- validation, evaluating the network that has the lowest value of Root Mean Square (RMS). In this case, the best result was obtained for a hierarchical architecture with two modules and one layer of hidden neurons. The airfoils developed for that network, in the regions of lower RMS, were compared with the same airfoils imported into the software XFoil

Desenvolvimento e teste de um protótipo de reator de plasma com gaiola catódica rotatória para nitretação em lote de pequenas peças

The technique of ion nitriding, despite being fully consolidated in the industry, has great limitations when applied to the treatment of small parts. This is because effects that occur due to non-uniformity of the electric field, generate localized heating in parts, damaging the uniformity of nitrided layer. In addition, because the samples are treated static parts thereof are untreated. To expand the use of plasma nitriding, this work presents the development, assembly and testing of a prototype plasma reactor with rotatory cathodic cage [patent pending], able to meet these needs, giving the material a uniform treatment and opening doors to industrial scale production. The samples tested with hexagonal nuts are 6.0 mm in diameter, made of stainless steel AISI 304 nitrided at a pressure of 1 mbar in an atmosphere of 20% H2 + 80% N2 for 1 h. After treatment, testing visual inspection, optical microscopy and microhardness were carried out to check the effectiveness of the process for uniformity and hardness of the parts. All samples exhibited uniform color, and matte brownish, unlike the untreated samples, silver color and gloss. The hardness of the surface (top and sides) was 65% and even higher than the original hardness. The nitrided layer showed great uniformity in microstructure and thickness. It is concluded, therefore, that the unit was effective constructed for the purposes for which it was designed

Desenvolvimento e avaliação de padrão de torque para calibração de torquímetros em três faixas de medição

The continuous development of instruments and equipment used as tools or torque measurement in the industry is demanding more accurate techniques in the use of this kind instrumentation, including development of metrological characteristics in torque measurement. The same happens with the needs in calibration services. There is a diversity of methods of hand torque tools in the market with different measuring range but without complaining with technical standards in terms of requirements of quality and reliability. However, actually there is no choice of a torque measuring standard that fulfils, with low cost, the needs for the calibration of hand torque tools in a large number of ranges. The objective of this thesis is to show the development and evaluation of a torque measuring standard device with a conception to allow the calibration of hand torque tools with three levels of torque with an single instrument, promoting reduction of costs and time in the calibration, also offering reliability for the evaluation of torque measuring instrument. To attend the demand in the calibration of hand torque tools it is necessary that the calibration laboratories have a big collection of torque measuring standards, to fulfills the needs of the costumer, what is very costly. The development of this type of torque measuring standard revealed a viable technique and economically making possible the calibration of hand torque tools in different nominal ranges through a single measurement system versatile, efficient and of easy operation

Determinação de Dados de Equilíbrio Líquido-Vapor para Sistemas Hidrocarbonetos e Desenvolvimento de uma Nova Célula Dinâmica

In the present work are established initially the fundamental relationships of thermodynamics that govern the equilibrium between phases, the models used for the description of the behavior non ideal of the liquid and vapor phases in conditions of low pressures. This work seeks the determination of vapor-liquid equilibrium (VLE) data for a series of multicomponents mixtures of saturated aliphatic hydrocarbons, prepared synthetically starting from substances with analytical degree and the development of a new dynamic cell with circulation of the vapor phase. The apparatus and experimental procedures developed are described and applied for the determination of VLE data. VLE isobarics data were obtained through a Fischer's ebulliometer of circulation of both phases, for the systems pentane + dodecane, heptane + dodecane and decane + dodecane. Using the two new dynamic cells especially projected, of easy operation and low cost, with circulation of the vapor phase, data for the systems heptane + decane + dodecane, acetone + water, tween 20 + dodecane, phenol + water and distillation curves of a gasoline without addictive were measured. Compositions of the equilibrium phases were found by densimetry, chromatography, and total organic carbon analyzer. Calibration curves of density versus composition were prepared from synthetic mixtures and the behavior excess volumes were evaluated. The VLE data obtained experimentally for the hydrocarbon and aqueous systems were submitted to the test of thermodynamic consistency, as well as the obtained from the literature data for another binary systems, mainly in the bank DDB (Dortmund Data Bank), where the Gibbs-Duhem equation is used obtaining a satisfactory data base. The results of the thermodynamic consistency tests for the binary and ternary systems were evaluated in terms of deviations for applications such as model development. Later, those groups of data (tested and approved) were used in the KijPoly program for the determination of the binary kij parameters of the cubic equations of state original Peng-Robinson and with the expanded alpha function. These obtained parameters can be applied for simulation of the reservoirs petroleum conditions and of the several distillation processes found in the petrochemistry industry, through simulators. The two designed dynamic cells used equipments of national technology for the determination Humberto Neves Maia de Oliveira Tese de Doutorado PPGEQ/PRH-ANP 14/UFRN of VLE data were well succeed, demonstrating efficiency and low cost. Multicomponents systems, mixtures of components of different molecular weights and also diluted solutions may be studied in these developed VLE cells

Opiniões de professores do ensino médio: refletindo sobre os projetos escolares e a interdisciplinaridade

Official documents indicate to a curriculum organization that promotes the dialogue in different areas of knowledge. Among the proposals strategies are the "School Projects". This research appears from the staff need evidenced in the development of practice of the researcher in recent years as Pedagogical Advisor in high school. The comments made in the daily work on the kinds of projects and how they were developed in the school, generated concerns. They aroused the interest in further the discussion, aiming to reflect with teachers about the implementation of a pedagogic action on the use of educational projects in the classroom, as a didactic strategy which promotes the learning of students. In this sense, it seeks to develop studies and discussions by the application of questionnaires and the holding of a workshop with teachers in the area of Science of Nature and Mathematics in private high school institutions from Natal, searching opinions of them as the preparation and development of school projects. As general purpose, it aims to contribute with elements to the reflection of the teachers on the use of this strategy of education. For both, we propose: the knowledge of ideas/opinions of teachers on planning, development and evaluation of projects, both disciplinary and interdisciplinary, identifying the main difficulties of these teachers about the work with projects at school; reviewing projects developed at school after the press conference in a meeting with teachers, incorporating the identified aspects as weak points. In the course of the methodology research, questionnaires were used with open and closed questions for the lifting of preliminary ideas for teachers in order to subsidize the planning of a developed meeting later in the school itself on the subject in question. 10 teachers took part of the first step and 17 in the second one (pressconference). In the third stage, an individual interview was carried out and analysis of projects already developed. It is observed that, as the main difficulty for the development of projects in school, pointed to the time factor in the planning team, followed by excessive working hours for teachers that, generally, also work in other schools. Some teachers say they do not develop projects for not having knowledge of how to develop school projects, neither disciplinary, nor interdisciplinary

Projetos de letramento na educação de jovens e adultos: o ensino da escrita em uma perspectiva emancipatória

This ethnographical research-action is included in the Applied Linguistics area and its study object is related to literacy projects (KLEIMAN, 2000), since they bring a new sense to the literacy practices in school and emphasizes the agentive writing character and the role of the discursive genres in the formation of literacy agents who aim at the action and the social change. Considering the emancipatory potential that these didactic organizations have in the civic literacy of those who live in social risk and vulnerability situations our aim in this investigation is: to reflect about the role of the redefinition of the literacy school practices and investigate how the action of teachers and students as literacy agents occur. The specific aims are: to promote literacy events which encourage the writing practice for the action and social change; to comprehend how the identity construction of the literacy student-agent occurs by the reflection of its agency process in the literacy projects; to identify teaching strategies and procedures which enable the development of emancipatory language practices; to investigate the axiological values constructed by the learners in and about the writing work in literacy projects. Our discussion is based on the language conception supported by Bakhtin (BAKHTIN/VOLOSHINOV, 2000; BAKHTIN, 1990, 2003); in literacy studies (KLEIMAN, 1995; BAYNHAM, 1995; BARTON; HAMILTON; IVANIC, 2000, LAZERE, 2005); on critical studies which defend the idea that the texts are ideological instruments able to give power to the individuals (MCLAREN, 1988, 1991, 1997, 1999, 2000, 2001; FREIRE, 1971, 1978, 1979, 1982, 1992, 1996, 2001a, 2001b, 2009; GIROUX, 1983, 1986, 1990, 1992, 1997, 1999, 2003; APPLE, 1989); on the social genre approach inspired by the New Rhetoric (BAZERMAN, 2005, 2006, 2007; MILLER, 1984, 2009). The data were generated between 2006 and 2010 in the Youth and Adult Education (YAE), in public schools in Natal-RN. The research permitted us to deduce, firstly, that the redefinition of the work with discursive genres provide the learner to read and write to act discursively in the social world, earning, thus, empowerment, autonomy and emancipation; secondly, that involving the students in literacy projects goes beyond didactic competence related to specificities and content domain. It is necessary that the teacher is certain about to whom, what, why and how to teach and that he/she gets a reflexive posture, becoming a learner as well; thirdly, that through the literacy practices which were developed, the collaborators of the research have constructed a more conscious and a more critical view in relation to the language and to the world where they live through the social-political writing and they have improved as interventive and politicized citizens

Lazer na terceira idade: desenvolvimento humano e qualidade de vida

The article aimed to understand the concept of leisure and understanding that older people have about their benefits to the quality of life as part of the idleness of the population. We used a sample of subjects living in the city of Bauru, SP, aged less than fifty years, of both sexes and economically disadvantaged class. It was used in literature, documentary and field. We developed an intervention project that aimed to education for leisure. It was the conclusion that public policies are necessary and qualified professionals for construction projects and equipment to expand the Recreation, spreading it and reaching the people of old age since previous stages of life. Materials with simple and low cost, the project of intervention, it reached the recreation-education and education for leisure satisfactorily.

Maturidade em gerenciamento de projetos no contexto da gestão estratégica no setor público: análise na Secretaria de Estado da Tributação do Rio Grande do Norte

This paperwork attempts to measure the project management maturity in the State Department of Taxation in Rio Grande do Norte. Project management has shown to be a critical component to any organization success, as the projects are directly related to a set of activities resulting into organizational innovations such as products, services and processes; and its improvement is directly aligned with the strategic management. Methodologically, this paperwork uses both a quantitative and qualitative approach that will be applied to the coordinators, sub-coordinators, and directors of the Regional Offices of the State Department of Taxation. In the theoretical reference it is about the public management and analyzes the strategic management in contemporary public administration. Presents the maturity in project management is by discussing the main models: CMM, Capability Maturity Model; PMMM, Project Management Maturity Model; OPM3, Organization Project Maturity Model and the Prado-MMGP, Modelo de Maturidade em Gerenciamento de Projetos. From this analysis, considering attributes as an aid in taking strategic positioning, access to the model, possibility of benchmarking and continuous improvement, the Prado-MMGP model was the most appropriate for this research process. It has been proved that the State Department of Taxation shows a very low project management maturity level. Regarding the acceptance of the maturity dimensions by the State Department, it is still in an early developmental stage, as one of the dimensions showed a poor performance while the rest showed a regular one. In contrast with similar organizations, the maturity results have shown to be below the national average. The maturity assessment enables in the institution the implementation of a plan for institutional growth with the creation of sector strategic and project management

Natal, outra cidade : o papel da Intendência Municipal no desenvolvimento de uma nova ordem urbana(1904-1929)

The present work regards, as its subject, the management of the urban space. It aims to survey the role assumed by the Conselho de Intendência Municipal de Natal (Municipal Stewardship Council of Natal) in the formation of a new urban order between the years of 1904 and 1929. For a better comprehension of the object of research, the milestone of the time span analyzed in this work was receded to the year of 1890, specifically at the first chapter of this dissertation. In this chapter, we will turn our attention towards an analysis of the referred council, on the regulation of its operation, the relations of this institution with the state government and its mechanisms of action in the city, among other topics. In the next chapter, we will delve into an elite who administrated the city of Natal during the first republic, understanding that the analysis of the formation of a modern city project by the Municipal Stewardship undergoes the comprehension of those who leaded this institution. In the third chapter, we will examine the limits of the municipal management to put into practice its projects to the upraise of a new Natal, between the years of 1904 and 1921. The last chapter, on its turn, presents a new Stewardship, reformulated after a process of administrative streamlining, and a city that transforms itself, especially during the O Grady tenure by receiving major constructions, which alter its main features. We will regard, as the main resources of this study, articles from the daily newspapers A República (The Republic) and Diário de Natal (Daily Natal), dictums, announcements, laws, state decrees and the messages disclosed by the state government. To build a way of analysis, we make use of authors such as Anthony Giddens, Peter Burke and Laurent Vidal, among many others who discuss concepts related to the proposed theme

Estudo da viabilidade do desenvolvimento de sistemas integrados baseados em redes em chip sem processadores: sistema IPNoSys

The increase of capacity to integrate transistors permitted to develop completed systems, with several components, in single chip, they are called SoC (System-on-Chip). However, the interconnection subsystem cans influence the scalability of SoCs, like buses, or can be an ad hoc solution, like bus hierarchy. Thus, the ideal interconnection subsystem to SoCs is the Network-on-Chip (NoC). The NoCs permit to use simultaneous point-to-point channels between components and they can be reused in other projects. However, the NoCs can raise the complexity of project, the area in chip and the dissipated power. Thus, it is necessary or to modify the way how to use them or to change the development paradigm. Thus, a system based on NoC is proposed, where the applications are described through packages and performed in each router between source and destination, without traditional processors. To perform applications, independent of number of instructions and of the NoC dimensions, it was developed the spiral complement algorithm, which finds other destination until all instructions has been performed. Therefore, the objective is to study the viability of development that system, denominated IPNoSys system. In this study, it was developed a tool in SystemC, using accurate cycle, to simulate the system that performs applications, which was implemented in a package description language, also developed to this study. Through the simulation tool, several result were obtained that could be used to evaluate the system performance. The methodology used to describe the application corresponds to transform the high level application in data-flow graph that become one or more packages. This methodology was used in three applications: a counter, DCT-2D and float add. The counter was used to evaluate a deadlock solution and to perform parallel application. The DCT was used to compare to STORM platform. Finally, the float add aimed to evaluate the efficiency of the software routine to perform a unimplemented hardware instruction. The results from simulation confirm the viability of development of IPNoSys system. They showed that is possible to perform application described in packages, sequentially or parallelly, without interruptions caused by deadlock, and also showed that the execution time of IPNoSys is more efficient than the STORM platform

KitSmart: Uma biblioteca de componentes para o desenvolvimento rigoroso de aplicações Java Card com o método B

The development of smart card applications requires a high level of reliability. Formal methods provide means for this reliability to be achieved. The BSmart method and tool contribute to the development of smart card applications with the support of the B method, generating Java Card code from B specifications. For the development with BSmart to be effectively rigorous without overloading the user it is important to have a library of reusable components built in B. The goal of KitSmart is to provide this support. A first research about the composition of this library was a graduation work from Universidade Federal do Rio Grande do Norte, made by Thiago Dutra in 2006. This first version of the kit resulted in a specification of Java Card primitive types byte, short and boolean in B and the creation of reusable components for application development. This work provides an improvement of KitSmart with the addition of API Java Card specification made in B and a guide for the creation of new components. The API Java Card in B, besides being available to be used for development of applications, is also useful as a documentation of each API class. The reusable components correspond to modules to manipulate specific structures, such as date and time. These structures are not available for B or Java Card. These components for Java Card are generated from specifications formally verified in B. The guide contains quick reference on how to specify some structures and how some situations were adapted from object-orientation to the B Method. This work was evaluated through a case study made through the BSmart tool, that makes use of the KitSmart library. In this case study, it is possible to see the contribution of the components in a B specification. This kit should be useful for B method users and Java Card application developers

Um método para desenvolvimento de abordagens generativas com composição de linguagens específicas de domínio

The software systems development with domain-specific languages has become increasingly common. Domain-specific languages (DSLs) provide increased of the domain expressiveness, raising the abstraction level by facilitating the generation of models or low-level source code, thus increasing the productivity of systems development. Consequently, methods for the development of software product lines and software system families have also proposed the adoption of domain-specific languages. Recent studies have investigated the limitations of feature model expressiveness and proposing the use of DSLs as a complement or substitute for feature model. However, in complex projects, a single DSL is often insufficient to represent the different views and perspectives of development, being necessary to work with multiple DSLs. In order to address new challenges in this context, such as the management of consistency between DSLs, and the need to methods and tools that support the development with multiple DSLs, over the past years, several approaches have been proposed for the development of generative approaches. However, none of them considers matters relating to the composition of DSLs. Thus, with the aim to address this problem, the main objectives of this dissertation are: (i) to investigate the adoption of the integrated use of feature models and DSLs during the domain and application engineering of the development of generative approaches; (ii) to propose a method for the development of generative approaches with composition DSLs; and (iii) to investigate and evaluate the usage of modern technology based on models driven engineering to implement strategies of integration between feature models and composition of DSLs