Bertrand model under incomplete information

We consider a Bertrand duopoly model with unknown costs. The firms' aim is to choose the price of its product according to the well-known concept of Bayesian Nash equilibrium. The chooses are made simultaneously by both firms. In this paper, we suppose that each firm has two different technologies, and uses one of them according to a certain probability distribution. The use of either one or the other technology affects the unitary production cost. We show that this game has exactly one Bayesian Nash equilibrium. We analyse the advantages, for firms and for consumers, of using the technology with highest production cost versus the one with cheapest production cost. We prove that the expected profit of each firm increases with the variance of its production costs. We also show that the expected price of each good increases with both expected production costs, being the effect of the expected production costs of the rival dominated by the effect of the own expected production costs.

Reconfigurable IEEE1451-FPGA based weblab infrastructure

Weblabs are spreading their influence in Science and Engineering (S&E) courses providing a way to remotely conduct real experiments. Typically, they are implemented by different architectures and infrastructures supported by Instruments and Modules (I&Ms) able to be remotely controlled and observed. Besides the inexistence of a standard solution for implementing weblabs, their reconfiguration is limited to a setup procedure that enables interconnecting a set of preselected I&Ms into an Experiment Under Test (EUT). Moreover, those I&Ms are not able to be replicated or shared by different weblab infrastructures, since they are usually based on hardware platforms. Thus, to overcome these limitations, this paper proposes a standard solution that uses I&Ms embedded into Field-Programmable Gate Array (FPGAs) devices. It is presented an architecture based on the IEEE1451.0 Std. supported by a FPGA-based weblab infrastructure able to be remotely reconfigured with I&Ms, described through standard Hardware Description Language (HDL) files, using a Reconfiguration Tool (RecTool).

Automated synthesis procedure of RF discrete tuning differential capacitance circuits

The paper presents a RFDSCA automated synthesis procedure. This algorithm determines several RFDSCA circuits from the top-level system specifications all with the same maximum performance. The genetic synthesis tool optimizes a fitness function proportional to the RFDSCA quality factor and uses the epsiv-concept and maximin sorting scheme to achieve a set of solutions well distributed along a non-dominated front. To confirm the results of the algorithm, three RFDSCAs were simulated in SpectreRF and one of them was implemented and tested. The design used a 0.25 mum BiCMOS process. All the results (synthesized, simulated and measured) are very close, which indicate that the genetic synthesis method is a very useful tool to design optimum performance RFDSCAs.

Comércio eletrónico em Angola: impacto e desafio face à internacionalização de uma empresa de transporte aéreo - caso TAAG

Dissertação apresentada ao Instituto Superior de Contabilidade e Administração do Porto para a obtenção do Grau de Mestre em Empreendedorismo e Internacionalização Orientação pela Professora Doutora: Ana Azevedo Manuela Patrício

Aparato para experimentação remota do lançamento de projéteis

Num sistema de ensino cada vez mais exigente, a experimentação assume um papel fundamental na aquisição e validação do conhecimento. No ensino da Física, a necessidade de compreender a influência do meio num dado conceito teórico leva a que a experimentação tenha um carácter obrigatório. Neste contexto, surgem três cenários capazes de suportar a aprendizagem dos conceitos teóricos adquiridos. A simulação que faz uso da velocidade e capacidades de cálculo do computador para obter o resultado de uma experiência, a experimentação tradicional em laboratório, na qual o aluno executa, presencialmente, a sua experiência e por último a experimentação remota, que permite a execução de uma experiência real sem a presença física do aluno. Esta dissertação apresenta o projeto de um aparato para experimentação remota do “Lançamento de projéteis”. De forma a providenciar um meio de ensino de Física mais flexível, o aparato desenvolvido permite, aos alunos, a determinação da aceleração da gravidade e o estudo da dependência do movimento de um projétil num conjunto de parâmetros. Este aparato, operado remotamente, é acedido via web, onde primeiramente é reservado um intervalo de tempo. O conjunto de parâmetros (“Bola”, “Altura de lançamento” e “Ângulo de lançamento”) da máquina permite suportar vários cenários de ensino da Física, com diferentes complexidades.