Discalculia do desenvolvimento: avalia����o da representa����o num��rica pela ZAREKI-R

O presente estudo investigou aspectos da representa����o num��rica (processamento num��rico e c��lculo) e mem��ria operacional de crian��as com transtornos de aprendizagem. Participaram 30 crian��as de idade entre 9 e 10 anos, ambos os g��neros, divididas em dois grupos: sem dificuldade em aritm��tica (SDA; N=11) e com dificuldade em aritm��tica (CDA; N=19), avaliadas pela ZAREKI-R, Matrizes Coloridas de Raven, o Blocos de Corsi e o BCPR. Crian��as CDA exibiram escores levemente mais baixos que as SDA quanto ao n��vel intelectual e nos Blocos de Corsi. Na ZAREKI-R apresentaram preju��zo nos subtestes ditado de n��meros, c��lculo mental, problemas aritm��ticos e total. Crian��as CDA apresentaram d��ficits espec��ficos em mem��ria operacional visuoespacial e comprometimento em processamento num��rico e c��lculo, compat��vel com discalculia do desenvolvimento.

Fundamentos de otimiza����o por intelig��ncia de enxames: uma vis��o geral

Este artigo apresenta uma breve revis��o de alguns dos mais recentes m��todos bioinspirados baseados no comportamento de popula����es para o desenvolvimento de t��cnicas de solu����o de problemas. As metaheur��sticas tratadas aqui correspondem ��s estrat��gias de otimiza����o por col��nia de formigas, otimiza����o por enxame de part��culas, algoritmo shuffled frog-leaping, coleta de alimentos por bact��rias e col��nia de abelhas. Os princ��pios biol��gicos que motivaram o desenvolvimento de cada uma dessas estrat��gias, assim como seus respectivos algoritmos computacionais, s��o introduzidos. Duas aplica����es diferentes foram conduzidas para exemplificar o desempenho de tais algoritmos. A finalidade �� enfatizar perspectivas de aplica����o destas abordagens em diferentes problemas da ��rea de engenharia.

Avalia����o do rendimento escolar: estudos e concep����o

No presente artigo, al��m de lan��ar m��o de informa����es da literatura, como comumente se faz, pe��o licen��a e me autorizo a emitir sobre avalia����o escolar, minhas pr��prias id��ias e opini��es, fruto de muitos anos de investiga����o, viv��ncia em salas de aula, problemas e reflex��o.

Percep����o do egresso de enfermagem sobre a contribui����o do curso para o exerc��cio do cuidado

O estudo avaliou a forma����o em enfermagem ancorada na problematiza����o e na aprendizagem baseada em problemas a partir da percep����o dos egressos. Trata-se de estudo transversal de natureza ex-post-facto. Os resultados foram analisados na triangula����o das abordagens quantitativa e qualitativa e na perspectiva hermen��utica dial��tica. Na abordagem quantitativa 180 egressos responderam um question��rio. Na qualitativa, 14 participaram das entrevistas, que buscaram sentidos relacionados ao cuidado ideal, para constru����o dos indicadores que revelassem a l��gica da avalia����o. Esses indicadores nortearam a escolha das quest��es para triangula����o. Os resultados apontaram que 85,1% dos egressos est��o inseridos no mercado de trabalho, 92,1% cursaram p��s-gradua����o e 99,1% acreditam apresentar forma����o necess��ria ao cuidado ��tico, humanizado e fundamentado. A an��lise dos dados aponta para forma����o comprometida com a constru����o da autonomia e do conhecimento, bem como articulada aos princ��pios do Sistema ��nico de Sa��de e do mundo do trabalho em enfermagem.

The application of preprocessing and cutting plane techniques for a class of production planning problems

This paper investigates properties of integer programming models for a class of production planning problems. The models are developed within a decision support system to advise a sales team of the products on which to focus their efforts in gaining new orders in the short term. The products generally require processing on several manufacturing cells and involve precedence relationships. The cells are already (partially) committed with products for stock and to satisfy existing orders and therefore only the residual capacities of each cell in each time period of the planning horizon are considered. The determination of production recommendations to the sales team that make use of residual capacities is a nontrivial optimization problem. Solving such models is computationally demanding and techniques for speeding up solution times are highly desirable. An integer programming model is developed and various preprocessing techniques are investigated and evaluated. In addition, a number of cutting plane approaches have been applied. The performance of these approaches which are both general and application specific is examined.

As diferentes ���personalidades��� do n��mero racional trabalhadas atrav��s da resolu����o de problemas

We address the different "personalities" of the rational number and the concept of proportionality, analyzing the possibilities for using the Mathematics Teaching and Learning through Problem-solving Method. This method is based on the principle that knowledge can be constructed through the use of problems that generate new concepts and new contents. The different meanings of rational number - rational point, quotient, fraction, ratio, and operator - are constructs that depend on mathematical theories in which they are imbedded and the situations that evoke them in problem-solving. Some data will be presented from continuing education courses for teachers, aiming to contribute to understanding regarding the different "personalities" of the rational number. In general, these "personalities" are not easily identified by teachers and students, which is the reason for the many difficulties encountered during problem-solving involving rational numbers. One of these "personalities", the ratio, provides the basis for the concept of proportionality, which is relevant because it is a unifying idea in mathematics.

O modelo de Romberg e o percurso metodol��gico de uma pesquisa qualitativa em educa����o de uma pesquisa qualitativa em educa����o

The objective of this study is to present the trajectory of a research project (ALLEVATO, 2005) whose phenomenon of interest is the teaching of mathematics using problem solving with computers. The text is an attempt to portray this trajectory, from the point of view of the methodological route followed by the researcher, which was based on two main axes: the guidance of the educator Thomas A. Romberg (1992), and the guidelines provided by the foundations of qualitative research. The study was developed during a doctoral course offered by the Graduate Program in Mathematics Education at the State University of S��o Paulo (UNESP), Rio Claro campus.

Analog nonderivative optimizers

Analog networks for solving convex nonlinear unconstrained programming problems without using gradient information of the objective function are proposed. The one-dimensional net can be used as a building block in multi-dimensional networks for optimizing objective functions of several variables.

Algorithms for network piecewise-linear programs: A comparative study

Piecewise-Linear Programming (PLP) is an important area of Mathematical Programming and concerns the minimisation of a convex separable piecewise-linear objective function, subject to linear constraints. In this paper a subarea of PLP called Network Piecewise-Linear Programming (NPLP) is explored. The paper presents four specialised algorithms for NPLP: (Strongly Feasible) Primal Simplex, Dual Method, Out-of-Kilter and (Strongly Polynomial) Cost-Scaling and their relative efficiency is studied. A statistically designed experiment is used to perform a computational comparison of the algorithms. The response variable observed in the experiment is the CPU time to solve randomly generated network piecewise-linear problems classified according to problem class (Transportation, Transshipment and Circulation), problem size, extent of capacitation, and number of breakpoints per arc. Results and conclusions on performance of the algorithms are reported.

Conditional reasoning: A key to assessing computer-based knowledge-building communication processes

This article describes a methodological approach to conditional reasoning in online asynchronous learning environments such as Virtual-U VGroups, developed by SFU, BC, Canada, consistent with the notion of meaning implication: If part of a meaning C is embedded in B and a part of a meaning B is embedded in A, then A implies C in terms of meaning [Piaget 91]. A new transcript analysis technique was developed to assess the flows of conditional meaning implications and to identify the occurrence of hypotheses and connections among them in two human science graduate mixed-mode online courses offered in the summer/spring session of 1997 by SFU. Flows of conditional meaning implications were confronted with Virtual-U VGroups threads and results of the two courses were compared. Findings suggest that Virtual-U VGroups is a knowledge-building environment although the tree-like Virtual-U VGroups threads should be transformed into neuronal-like threads. Findings also suggest that formulating hypotheses together triggers a collaboratively problem-solving process that scaffolds knowledge-building in asynchronous learning environments: A pedagogical technique and an built-in tool for formulating hypotheses together are proposed. �� Springer Pub. Co.

Conservation laws for non-potential operators

A study was developed in order to build a function M invariant in time, by means of Hamiltonian's formulation, taking into account the equation associated to the problem, showing that starting from this function the equation of motion of the system with the contour conditions for non-conservative considered problems can be obtained. The Hamiltonian method is extended for these kind of systems in order to validate for non-potential operators through variational approach.

Projeto E an��lise de uma rede neural para resolver problemas de programa����o din��mica

Systems based on artificial neural networks have high computational rates due to the use of a massive number of simple processing elements and the high degree of connectivity between these elements. Neural networks with feedback connections provide a computing model capable of solving a large class of optimization problems. This paper presents a novel approach for solving dynamic programming problems using artificial neural networks. More specifically, a modified Hopfield network is developed and its internal parameters are computed using the valid-subspace technique. These parameters guarantee the convergence of the network to the equilibrium points which represent solutions (not necessarily optimal) for the dynamic programming problem. Simulated examples are presented and compared with other neural networks. The results demonstrate that proposed method gives a significant improvement.

Otimiza����o global para os problemas de redu����o H2 de modelos e redu����o H2 da ordem do controlador

A branch and bound algorithm is proposed to solve the H2-norm model reduction problem and the H2-norm controller reduction problem, with conditions assuring convergence to the global optimum in finite time. The lower and upper bounds used in the optimization procedure are obtained through linear matrix inequalities formulations. Examples illustrate the results.

On the solution of mathematical programming problems with equilibrium constraints

Mathematical programming problems with equilibrium constraints (MPEC) are nonlinear programming problems where the constraints have a form that is analogous to first-order optimality conditions of constrained optimization. We prove that, under reasonable sufficient conditions, stationary points of the sum of squares of the constraints are feasible points of the MPEC. In usual formulations of MPEC all the feasible points are nonregular in the sense that they do not satisfy the Mangasarian-Fromovitz constraint qualification of nonlinear programming. Therefore, all the feasible points satisfy the classical Fritz-John necessary optimality conditions. In principle, this can cause serious difficulties for nonlinear programming algorithms applied to MPEC. However, we show that most feasible points do not satisfy a recently introduced stronger optimality condition for nonlinear programming. This is the reason why, in general, nonlinear programming algorithms are successful when applied to MPEC.

Lyapounov stability for impulsive dynamical systems

This article addresses the problem of stability of impulsive control systems whose dynamics are given by measure driven differential inclusions. One important feature concerns the adopted solution which allows the consideration of systems whose singular dynamics do not satisfy the so-called Frobenius condition. After extending the conventional notion of control Lyapounov pair for impulsive systems, some stability conditions of the Lyapounov type are given. Some conclusions follow the outline of the proof of the main result.