Automated design of microwave discrete tuning differential capacitance circuits in Si-integrated technologies

A genetic algorithm used to design radio-frequency binary-weighted differential switched capacitor arrays (RFDSCAs) is presented in this article. The algorithm provides a set of circuits all having the same maximum performance. This article also describes the design, implementation, and measurements results of a 0.25 lm BiCMOS 3-bit RFDSCA. The experimental results show that the circuit presents the expected performance up to 40 GHz. The similarity between the evolutionary solutions, circuit simulations, and measured results indicates that the genetic synthesis method is a very useful tool for designing optimum performance RFDSCAs.

Analysis of support for modularity in object teams based on design patterns

Dissertação de Mestrado em Engenharia Informática

A Design methodology for integrated inductor-based DC-DC converters

A design methodology for monolithic integration of inductor based DC-DC converters is proposed in this paper. A power loss model of the power stage, including the drive circuits, is defined in order to optimize efficiency. Based on this model and taking as reference a 0.35 mu m CMOS process, a buck converter was designed and fabricated. For a given set of operating conditions the defined power loss model allows to optimize the design parameters for the power stage, including the gate-driver tapering factor and the width of the power MOSFETs. Experimental results obtained from a buck converter at 100 MHz switching frequency are presented to validate the proposed methodology.

From design-for-test to design-for-debug-and-test: analysis of requirements and limitations for 1149.1

The increasing complexity of VLSI circuits and the reduced accessibility of modern packaging and mounting technologies restrict the usefulness of conventional in-circuit debugging tools, such as in-circuit emulators for microprocessors and microcontrollers. However, this same trend enables the development of more complex products, which in turn require more powerful debugging tools. These conflicting demands could be met if the standard scan test infrastructures now common in most complex components were able to match the debugging requirements of design verification and prototype validation. This paper analyses the main debug requirements in the design of microprocessor-based applications and the feasibility of their implementation using the mandatory, optional and additional operating modes of the standard IEEE 1149.1 test infrastructure.

Design state exploration applied to the development of a remote lab for projectile launch experiments

This paper describes the application of Design State Exploration techniques in the development of a remote lab for projectile motion experiments. The application was enabled by the existence of two independent teams: one composed of a series of internships that started first and another with two grantees that started a few months later. The paper presents evidence on how this approach provided gains in the development process conducted by the second team that benefited from design state exploration studies performed by the first team. This particular aspect is highlighted in relation to the work already presented in the 10th Remote Engineering and Virtual Instrumentation (REV) conference.

Using SysML in systems design

System of systems involves several secondary systems working together with its creation gathering the knowledge of several distinct disciplines and teams, each one with their own background and methods, leading to a difficult communication between them. SysML, a language originated from UML, enables that communication, without background interference, with the use of a rich notation for systems design. This paper analyzes its use through the experience gained in the design of a chemical system with SysML.

Addressing software impact in the design of remote laboratories

Remote Laboratories or WebLabs constitute a first-order didactic resource in engineering faculties. However, in many cases, they lack a proper software design, both in the client and server side, which degrades their quality and academic usefulness. This paper presents the main characteristics of a Remote Laboratory, analyzes the software technologies to implement the client and server sides in a WebLab, and correlates these technologies with the characteristics to facilitate the selection of a technology to implement a WebLab. The results obtained suggest the adoption of a Service Oriented Laboratory Architecture-based approach for the design of future Remote Laboratories so that client-agnostic Remote Laboratories and Remote Laboratory composition are enabled. The experience with the real Remote Laboratory, WebLab-Deusto, is also presented.

Particle swarm design of digital circuits

Swarm Intelligence (SI) is the property of a system whereby the collective behaviors of (unsophisticated) agents interacting locally with their environment cause coherent functional global patterns to emerge. Particle swarm optimization (PSO) is a form of SI, and a population-based search algorithm that is initialized with a population of random solutions, called particles. These particles are flying through hyperspace and have two essential reasoning capabilities: their memory of their own best position and knowledge of the swarm's best position. In a PSO scheme each particle flies through the search space with a velocity that is adjusted dynamically according with its historical behavior. Therefore, the particles have a tendency to fly towards the best search area along the search process. This work proposes a PSO based algorithm for logic circuit synthesis. The results show the statistical characteristics of this algorithm with respect to number of generations required to achieve the solutions. It is also presented a comparison with other two Evolutionary Algorithms, namely Genetic and Memetic Algorithms.

A fractional calculus perspective in the evolutionary design of combinational circuits

This paper analyses the performance of a genetic algorithm (GA) in the synthesis of digital circuits using two novel approaches. The first concept consists in improving the static fitness function by including a discontinuity evaluation. The measure of variability in the error of the Boolean table has similarities with the function continuity issue in classical calculus. The second concept extends the static fitness by introducing a fractional-order dynamical evaluation.

A qualitative assessment of modularity in CaesarJ components based on implementations of design patterns

Tese de Mestrado em Engenharia Informática

Investigação de lipofuscina em miócitos cardíacos de camundongos após tratamento com oxamniquine

A fluorescencia natural devida à presença de corpos de lipofuscina foi pesquisada em miócitos cardíacos de camundongos adultos jovens tratados com oxamniquine. O objetivo foi buscar uma evidência de indução de envelhecimento celular precoce, com base em dados prévios de acentuação poliploidia, promovida pela droga. Comparando o miocárdio dos camundongos tratados com animais contrôle jovens e velhos, não foi observada a presença de lipofuscina nos seus miócitos. Isto possivelmente se deva a um não comprometimento da eficiência das lipases lisossomiais apesar da acentuação do fenômeno de poliploidização induzida pela droga.

Novel techniques for the design and practical realization of switched-capacitor circuits in deep-submicron CMOS technologies

Dissertação apresentada para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Desenho universal para a aprendizagem: construindo práticas pedagógicas inclusivas

O presente artigo tem como objetivo apresentar uma grelha de planificação da intervenção facilitadora do desenvolvimento de práticas pedagógicas inclusivas. Para o efeito, procedeu-se a uma revisão da literatura centrada nos conceitos de Educação Inclusiva e de Desenho Universal para a Aprendizagem (Universal Design for Learning), a qual permitiu identificar e fundamentar a pertinência das dimensões a considerar na planificação da intervenção pedagógica, de modo a assegurar o acesso, a participação e o sucesso de todos os alunos. Com a apresentação da grelha de planificação da intervenção pedagógica pretende-se, em última análise, sublinhar a necessidade e a importância de desenvolver processos de planificação que disponibilizem formas diversificadas de motivação e envolvimento dos alunos, que equacionem múltiplos processos de apresentação dos conteúdos a aprender e, por último, que possibilitem a utilização de diversas formas de ação e expressão por parte dos alunos.

O desenvolvimento de competências sociais na educação de infância: a música como estratégia de intervenção

Relatório da Prática Profissional Supervisionada Mestrado em Educação Pré-Escolar

Apropriação de conteúdos do conhecimento explícito da língua por alunos do 2.º ano do 1.º ciclo do ensino básico

Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1.º e 2.º Ciclo do Ensino Básico