Rodrigo Dalla Vecchia

Modelagem Matemática e Tecnologias de Informação e Comunicação: a realidade do mundo cibernético como um vetor de virtualização

In this paper, we build a theoretical-philosophical interlacing that aims to discuss the relationship between Mathematical Modeling and the reality of the cyberworld. This reality is particularly viewed as a possible vector of virtualization, i.e. as an element that enables the transformation of the perception of the problem involving a particular situation or entity. To do so, we make an association between mathematical modeling and transformations that involve the ways of being denoted by real, possible, current and virtual, through the four Aristotelian causes. Complementing this association, we assume a conception of problem that allows a consolidation among the established relationships and also a conception of reality that sees the cyberworld as one of its dimensions. Finally, we present an example of mathematical modeling from the classroom, aiming to characterize the reality of the cyberworld as a vector of virtualization.

IEEE 802.11 wireless location and network security mechanism through fingerprint, triangulation and dynamic obstacle identification

This paper presents the results obtained in the development of a security mechanism for internet access control, based on the physical location of wireless stations. To achieve such a mechanism a wireless location system was develop, so that the network infrastructure can dynamically reconfigure proxy/firewall rules. To locate the wireless stations with the precision needed in this system, two techniques was used: amplitude fingerprint and amplitude triangulation. We also build a dynamic obstacle attenuation identifier due the fact that this obstacles can interfer in the location process. The dynamic obstacles attenuation was incorporate in the location technique to achieve a better precision in this process. After identifying the wireless station, the security system can apply the security policy defined to a specific physical area. In order to validate the system, we used a academic environment with classroom based security rules. In this environment, each classroom is defined by a specific subnet and the security rules are defined by the teacher based on the class educational objectives. The wireless network is defined in a unique subnet, differing from all the classroom networks. The system goal is to apply the class-based security restrictions to all the devices physically located in the specific classroom, been either wired or wireless stations.

Proposição de um modelo de otimização para programação da produção em Sistema Flexível de Manufatura (FMS) com tempos de setup dependentes da sequência: a combinação de esforços em sequenciamento e tempos de preparação na indústria eletrônica

Este trabalho tem como proposito pesquisar e auxiliar a programacao da producao na industria eletronica, importante setor da economia. A pesquisa e desenvolvida em um Sistema Flexivel de Manufatura (FMS - Flexible Manufacturing System) responsavel pela montagem de placas de circuito impresso com tempos de setup dependentes da sequencia de producao. O campo de estudo sugerido apresenta fatores comuns encontrados na manufatura de equipamentos eletronicos caracterizados por trabalhar em ambientes HMLV (high-mix, low-volume). E proposto um modelo matematico visando minimizar o makespan, ou seja, a duracao total de atendimento da programacao, a partir da combinacao de esforcos em sequenciamento da producao e tempos de preparacao. Os achados de pesquisa evidenciaram a possibilidade de utilizacao estrategica de duas logicas de setup para execucao da programacao. A aplicacao da alternância das estrategias, a partir dos desdobramentos da proposta de trabalho deste artigo, e o que gera a minimizacao do makespan.

The Construction of Electronic Games as an Environment for Mathematics Education

The main aim of this chapter is to reflect on the teaching and learning of mathematics as processes carried out through the construction of electronic games. Here, game construction is associated with the perspective of Mathematical Modeling, emphasizing the mathematical aspects specific to the programming language used by the software Scratch. In particular, we present the implicit and the explicit mathematics embedded in the construction of two games developed by university students. We believe that the quest for associations between mathematics and computational languages may help enhance the teaching and learning of mathematics as a whole. More specifically, we understand that Mathematical Modeling that takes place in the process of electronic games construction may contribute to the mathematisation process, when it considers the students’ choices and interests, and takes into account the concerns with learning as it occurs throughout the construction process.