Otimização de forma aplicando B-splines sob critério integral de tensões

This work proposes a computational methodology to solve problems of optimization in structural design. The application develops, implements and integrates methods for structural analysis, geometric modeling, design sensitivity analysis and optimization. So, the optimum design problem is particularized for plane stress case, with the objective to minimize the structural mass subject to a stress criterion. Notice that, these constraints must be evaluated at a series of discrete points, whose distribution should be dense enough in order to minimize the chance of any significant constraint violation between specified points. Therefore, the local stress constraints are transformed into a global stress measure reducing the computational cost in deriving the optimal shape design. The problem is approximated by Finite Element Method using Lagrangian triangular elements with six nodes, and use a automatic mesh generation with a mesh quality criterion of geometric element. The geometric modeling, i.e., the contour is defined by parametric curves of type B-splines, these curves hold suitable characteristics to implement the Shape Optimization Method, that uses the key points like design variables to determine the solution of minimum problem. A reliable tool for design sensitivity analysis is a prerequisite for performing interactive structural design, synthesis and optimization. General expressions for design sensitivity analysis are derived with respect to key points of B-splines. The method of design sensitivity analysis used is the adjoin approach and the analytical method. The formulation of the optimization problem applies the Augmented Lagrangian Method, which convert an optimization problem constrained problem in an unconstrained. The solution of the Augmented Lagrangian function is achieved by determining the analysis of sensitivity. Therefore, the optimization problem reduces to the solution of a sequence of problems with lateral limits constraints, which is solved by the Memoryless Quasi-Newton Method It is demonstrated by several examples that this new approach of analytical design sensitivity analysis of integrated shape design optimization with a global stress criterion purpose is computationally efficient

Método de Otimização Topológica em Estruturas Tridimensionais

The topology optimization problem characterize and determine the optimum distribution of material into the domain. In other words, after the definition of the boundary conditions in a pre-established domain, the problem is how to distribute the material to solve the minimization problem. The objective of this work is to propose a competitive formulation for optimum structural topologies determination in 3D problems and able to provide high-resolution layouts. The procedure combines the Galerkin Finite Elements Method with the optimization method, looking for the best material distribution along the fixed domain of project. The layout topology optimization method is based on the material approach, proposed by Bendsoe & Kikuchi (1988), and considers a homogenized constitutive equation that depends only on the relative density of the material. The finite element used for the approach is a four nodes tetrahedron with a selective integration scheme, which interpolate not only the components of the displacement field but also the relative density field. The proposed procedure consists in the solution of a sequence of layout optimization problems applied to compliance minimization problems and mass minimization problems under local stress constraint. The microstructure used in this procedure was the SIMP (Solid Isotropic Material with Penalty). The approach reduces considerably the computational cost, showing to be efficient and robust. The results provided a well defined structural layout, with a sharpness distribution of the material and a boundary condition definition. The layout quality was proporcional to the medium size of the element and a considerable reduction of the project variables was observed due to the tetrahedrycal element

O Desenvolvimento local sustentável no semi-árido nordestino: um estudo de caso na comunidade de mirandas, Caraúbas/RN

Brazil s semi-arid region is an immense territory characterized by a mosaic of natural environments and human settlements. Inside this multifaceted framework, there are problems that are specific to the region (the water resources situation, for example) while others are more universal (such as the inequality between men and women). The circumstances that give rise to these problems are complex and require a holistic view so that our understanding can go beyond the simple concept that this is a problem region . The semi-arid must be perceived as a viable area in need of a new analysis, taking into account its successes, limitations, challenges and the strategic public policy framework that guarantees its sustainable development. The dissertation analyzes, from a sustainable local development perspective, the experience of the Northeastern Brazil Groundwater Project (PROASNE), carried out from 2001 to 2003, in partnership with the Waters and Sewers Company of Rio Grande do Norte (CAERN) in the rural community of Mirandas, municipality of Caraúbas/RN, situated in the middle of the northeastern Brazil semi-arid region

Em direção a uma representação para equações algébricas :uma lógica equacional local

The intervalar arithmetic well-known as arithmetic of Moore, doesn't possess the same properties of the real numbers, and for this reason, it is confronted with a problem of operative nature, when we want to solve intervalar equations as extension of real equations by the usual equality and of the intervalar arithmetic, for this not to possess the inverse addictive, as well as, the property of the distributivity of the multiplication for the sum doesn t be valid for any triplet of intervals. The lack of those properties disables the use of equacional logic, so much for the resolution of an intervalar equation using the same, as for a representation of a real equation, and still, for the algebraic verification of properties of a computational system, whose data are real numbers represented by intervals. However, with the notion of order of information and of approach on intervals, introduced by Acióly[6] in 1991, the idea of an intervalar equation appears to represent a real equation satisfactorily, since the terms of the intervalar equation carry the information about the solution of the real equation. In 1999, Santiago proposed the notion of simple equality and, later on, local equality for intervals [8] and [33]. Based on that idea, this dissertation extends Santiago's local groups for local algebras, following the idea of Σ-algebras according to (Hennessy[31], 1988) and (Santiago[7], 1995). One of the contributions of this dissertation, is the theorem 5.1.3.2 that it guarantees that, when deducing a local Σ-equation E t t in the proposed system SDedLoc(E), the interpretations of t and t' will be locally the same in any local Σ-algebra that satisfies the group of fixed equations local E, whenever t and t have meaning in A. This assures to a kind of safety between the local equacional logic and the local algebras

Multicast packing problem: abordagem multiobjetivo

This work presents a algorithmic study of Multicast Packing Problem considering a multiobjective approach. The first step realized was an extensive review about the problem. This review serverd as a reference point for the definition of the multiobjective mathematical model. Then, the instances used in the experimentation process were defined, this instances were created based on the main caracteristics from literature. Since both mathematical model and the instances were definined, then several algoritms were created. The algorithms were based on the classical approaches to multiobjective optimization: NSGA2 (3 versions), SPEA2 (3 versions). In addition, the GRASP procedures were adapted to work with multiples objectives, two vesions were created. These algorithms were composed by three recombination operators(C1, C2 e C3), two operator for build solution, a mutation operator and a local search procedure. Finally, a long experimentation process was performed. This process has three stages: the first consisted of adjusting the parameters; the second was perfomed to indentify the best version for each algorithm. After, the best versions for each algorithm were compared in order to identify the best algorithm among all. The algorithms were evaluated based on quality indicators and Hypervolume Multiplicative Epsilon

Açude do cais: uma proposta de aplicação de uma sequência de atividades didáticas em um contexto real

Currently it is expected that science education will enable a more comprehensive conception of the world and of the relationship between scientific knowledge, technology and society. Thus, we seek the science teaching attend around contexts related to science, technology and society (STS). According CTS approaches, the science education should promote learning in the scientific, technological and social fields, from experienced real contexts, generating motivation to students, offering them tools to work as scientifically literate citizens. For this, it becomes crucial to resort to innovative activities and the various methodologies and appropriate teaching materials, and there is a lack of this perspective in general basic education, which drives the practice of an STS approach. Therefore, the aim of this research is the production of an instructional sequence for the exploration of the theme: "The quality of the water in the municipality of Cuité-PB," according to focus CTS in the 2nd year of high school. The choice of this topic is due to the problem caused by the quality of water in this municipality, with the concern to address an issue that came to work the critical / reflective understanding of a real context, in order to sensitize students to the importance of scientific / technological knowledge. The selection criteria of STS subjects were also observed. In this research the materials were produced and applied by the teacher / researcher. For data collection we used the observation and analysis of student records. The results were encouraging in the sense of participation, motivation and skill acquisition. This research contributes to the teaching of science with a focus STS, as well as encourage the use of perspective in new contexts with real questioning

Políticas públicas, desenvolvimento local e participação social nas instâncias de governança associadas ao turismo no Rio Grande do Norte

In contemporary dynamics, a change is observed in the institutional structure of the state, culminating in several policies for the tourist sector which promote a new management format. The from this view, the Tourism Regionalization Macro Program (TRP), considered a significant program to Ministry of Tourism, arose as an answer to this new reality, having as strategy a joint working of structuring and promotion turned at decentralization of actions, valuing the residents participation in the search of the permanent dialogue between peers and revaluation of places and territories, based in the regionalization process. Based on this bias, this study aims to examine the role of the Tourism State Council of Rio Grande do Norte, with regard to the tourism planning, trying to understand it and solve it as governance Instance, through the Tourism Regionalization Program interventions, given the participation context of its actors and agents. For purposes of this study is delimited as time frame the year 2007 at 2014, understanding that it was this time, there was greater council members accession, as well as different types of sectors representation of civil society, as a result of a tourism public policy based on principles of innovation and participation. In relation to the research problem, this study is conceptualized as a qualitative and the chosen method is the materialist dialectic. Still on the methodological options, utilize the Content Analysis. The results show that the institutionalization of governance instance as the Conetur does not contributes, ideally, in the planning and management process of participatory and integrated tourist activity, facing a fair direction of your space production. The research indicates that there are debates, discussions and guidelines (still in a timely and targeted form), but not reverberates practical effects, by act in a conjuncture that Is strategically designed for political and economic power game, setting the hegemonic actors performance, which uses this arena to instill personal desires and wishes, that are decided in absentia to the council.