Do discurso da impunidade à impunização: o sistema penal do capitalismo brasileiro e a destruição da democracia

Neste trabalho pretendemos demonstrar que a utilização da impunidade como suposto motivador criminal - seja como conceito, seja como conteúdo -, é equivocada na medida em que aquela não passa de um defeito funcional advindo do descompasso entre o programa criminalizador primário e a criminalização secundária, ainda que intermediada pela criminalização terciária (midiática). A consequência dessa paralaxe seria a migração léxica não só do verbete impunidade para o verbete impunização, senão a consideração de que essa não passa de um apontar de dedo político, útil ao sistema penal que, descaradamente, utiliza-se daquela desafinação para manter ou aumentar o seu poder punitivo. Para tanto, utilizamo-nos do método indiciário, haja vista não nos ser possível decifrar todas as causas e consequências que envolvem o discurso da impunidade criminógena, embora isso não nos tenha impedido de concluir que a seletividade inerente ao sistema penal, equivocadamente nomeada de impunidade, serve, em última medida, quando bem utilizada, como corretivo da voracidade do poder punitivo. Corretivo que, todavia, para exercer todo seu poder curativo, não pode continuar se valendo da própria seletividade, senão de uma redução do próprio poder punitivo.

Studies of inverter ratings of BDFM adjustable speed drive or generator systems

This paper discusses the inverter ratings of Brushless Doubly-Fed Machine (BDFM) adjustable speed drive (ASD) or generator (ASG) systems. Based on the per phase equivalent circuit model, the ratings of the two inverters in a bidirectional converter are evaluated individually. An approach to minimise the total inverter rating is presented, taking into account power factor constraints of the power grid. The effects of speed deviation and control winding excitation on the inverter ratings are discussed. Predictions of inverter ratings are presented with experimental verification. A design example is also provided in which the total inverter rating is minimised for a practical BDFM based ASG system. © 2005 IEEE.

Electromagnetic-thermal design optimization of the brushless doubly fed induction generator

In view of its special features, the brushless doubly fed induction generator (BDFIG) shows high potentials to be employed as a variable-speed drive or wind generator. However, the machine suffers from low efficiency and power factor and also high level of noise and vibration due to spatial harmonics. These harmonics arise mainly from rotor winding configuration, slotting effects, and saturation. In this paper, analytical equations are derived for spatial harmonics and their effects on leakage flux, additional loss, noise, and vibration. Using the derived equations and an electromagnetic-thermal model, a simple design procedure is presented, while the design variables are selected based on sensitivity analyses. A multiobjective optimization method using an imperialist competitive algorithm as the solver is established to maximize efficiency, power factor, and power-to-weight ratio, as well as to reduce rotor spatial harmonic distortion and voltage regulation simultaneously. Several constraints on dimensions, magnetic flux densities, temperatures, vibration level, and converter voltage and rating are imposed to ensure feasibility of the designed machine. The results show a significant improvement in the objective function. Finally, the analytical results of the optimized structure are validated using finite-element method and are compared to the experimental results of the D180 frame size prototype BDFIG. © 1982-2012 IEEE.

Remote electricity actuation and monitoring mote

This work presents the design and evaluation of the REAM (Remote Electricity Actuation and Monitoring) node based around the modular Tyndall Mote platform. The REAM node enables the user to remotely actuate power to a mains power extension board while sampling the current, voltage, power and power factor of the attached load. The node contains a current transformer interfaced to an Energy Metering IC which continuously samples current and voltage. These values are periodically read from the part by a PIC24 microcontroller, which calculates the RMS current and voltage, power factor and overall power. The resultant values can then be queried wirelessly employing the Tyndall 802.15.4 compliant wireless module.

Application-Specific Instruction Set Processor for SoC implementation of Modern Signal Processing Algorithms

A novel application-specific instruction set processor (ASIP) for use in the construction of modern signal processing systems is presented. This is a flexible device that can be used in the construction of array processor systems for the real-time implementation of functions such as singular-value decomposition (SVD) and QR decomposition (QRD), as well as other important matrix computations. It uses a coordinate rotation digital computer (CORDIC) module to perform arithmetic operations and several approaches are adopted to achieve high performance including pipelining of the micro-rotations, the use of parallel instructions and a dual-bus architecture. In addition, a novel method for scale factor correction is presented which only needs to be applied once at the end of the computation. This also reduces computation time and enhances performance. Methods are described which allow this processor to be used in reduced dimension (i.e., folded) array processor structures that allow tradeoffs between hardware and performance. The net result is a flexible matrix computational processing element (PE) whose functionality can be changed under program control for use in a wider range of scenarios than previous work. Details are presented of the results of a design study, which considers the application of this decomposition PE architecture in a combined SVD/QRD system and demonstrates that a combination of high performance and efficient silicon implementation are achievable. © 2005 IEEE.

Multiple Input Governor Control for a Diesel Generating Set

The paper presents a multiple input single output fuzzy logic governor algorithm that can be used to improve the transient response of a diesel generating set, when supplying an islanded load. The proposed governor uses the traditional speed input in addition to voltage and power factor to modify the fuelling requirements during various load disturbances. The use of fuzzy logic control allows the use of PID type structures that can provide variable gain strategies to account for non-linearities in the system. Fuzzy logic also provides a means of processing other input information by linguistic reasoning and a logical control output to aid the governor action during transient disturbance. The test results were obtained using a 50 kVA naturally aspirated diesel generator testing facility. Both real and reactive load tests were conducted. The complex load test results demonstrate that, by using additional inputs to the governor algorithm, enhanced generator transient speed recovery response can be obtained.

Investigation of the process energy demand in polymer extrusion: a brief review and an experimental study

Extrusion is one of the fundamental production methods in the polymer processing industry and is used in the production of a large number of commodities in a diverse industrial sector. Being an energy intensive production method, process energy efficiency is one of the major concerns and the selection of the most energy efficient processing conditions is a key to reducing operating costs. Usually, extruders consume energy through the drive motor, barrel heaters, cooling fans, cooling water pumps, gear pumps, etc. Typically the drive motor is the largest energy consuming device in an extruder while barrel/die heaters are responsible for the second largest energy demand. This study is focused on investigating the total energy demand of an extrusion plant under various processing conditions while identifying ways to optimise the energy efficiency. Initially, a review was carried out on the monitoring and modelling of the energy consumption in polymer extrusion. Also, the power factor, energy demand and losses of a typical extrusion plant were discussed in detail. The mass throughput, total energy consumption and power factor of an extruder were experimentally observed over different processing conditions and the total extruder energy demand was modelled empirically and also using a commercially available extrusion simulation software. The experimental results show that extruder energy demand is heavily coupled between the machine, material and process parameters. The total power predicted by the simulation software exhibits a lagging offset compared with the experimental measurements. Empirical models are in good agreement with the experimental measurements and hence these can be used in studying process energy behaviour in detail and to identify ways to optimise the process energy efficiency.

A floating point CORDIC based SVD processor

An SVD processor system is presented in which each processing element is implemented using a simple CORDIC unit. The internal recursive loop within the CORDIC module is exploited, with pipelining being used to multiplex the two independent micro-rotations onto a single CORDIC processor. This leads to a high performance and efficient hardware architecture. In addition, a novel method for scale factor correction is presented which only need be applied once at the end of the computation. This also reduces the computation time. The net result is an SVD architecture based on a conventional CORDIC approach, which combines high performance with high silicon area efficiency.

Retificador trifásico controlado com fator de potência quase unitário

Dissertação de Mestrado para obtenção do grau de Mestre em Engenharia Eletrotécnica Ramo Automação e Eletrónica Industrial

Retificador monofásico com fator de potência quase unitário

Dissertação para a obtenção do grau de Mestre em Engenharia Eletrotécnica Ramo de Automação e Eletrónica Industrial

Compensação da energia reactiva com minimização de perturbações sobre a rede eléctrica

Trabalho Final de Mestrado para a obtenção de grau de Mestre em Engenharia Electrotécnica Ramo de Automação e Electrónica Industrial

Otimização de consumo energético de equipamento de grande potência

Um dos princípios da Gestão é: “If you cannot measure it, you cannot improve it.” In The Economist – 26.Dez.2008, idea of 19th century English physicist Lord Kelvin. Embora seja uma afirmação aplicável à gestão económica, também pode ser utilizada no domínio da gestão da energia. Este trabalho surge da necessidade sentida pela empresa Continental - Industria Têxtil do Ave, S.A. em efetuar uma atualização dos seus standards de produção, minimizando os seus consumos de eletricidade e gás natural. Foi necessário efetuar o levantamento dos consumos em diversas máquinas e equipamentos industriais, caracterizando e analisando os consumos ao longo de todo o processo produtivo. Para o tratamento de dados recolhidos foi desenvolvida uma folha de cálculo em MS Office ExcelTM com metodologia adequada ao equipamento em análise, que dará apoio ao decisor para a identificação dos aspetos que melhorem o processo produtivo e garantam uma elevada eficiência energética. Porém, não se enquadra no âmbito do Plano Nacional de Racionalização de Energia, sendo uma “auditoria energética” ao processo produtivo. Recentemente, a empresa, tem vindo a utilizar equipamentos eletrónicos que permitem otimizar o funcionamento mecânico dos equipamentos e das potências instaladas dos transformadores, na tentativa de racionalizar o consumo da energia elétrica. Outros equipamentos como, conversores de frequência para controlo de motores, balastros eletrónicos que substituem os convencionais balastros ferromagnéticos das lâmpadas de descarga fluorescente, têm sido incluídos ao nível das instalações elétricas, sendo gradualmente substituída a eletromecânica pela eletrónica. Este tipo de soluções vem deteriorar as formas de onda da corrente e da tensão do sistema pela introdução de distorções harmónicas. Faz ainda parte deste trabalho, um estudo de uma solução que melhore, simultaneamente o fator de potência e reduza as harmónicas presentes num posto de transformação localizado no seio da fábrica. Esta solução, permite melhorar a qualidade da energia elétrica e as condições de continuidade de serviço, garantindo melhores condições de exploração e incrementando a produtividade da empresa.

Co3M2S2 (M ¼ Sn, In) shandites as tellurium-free thermoelectrics

Chemical substitution in Co3Sn2-xInxS2 (0 # x # 2) enables tuning of the Fermi level within narrow bands of Co d-states. This results in a compositionally induced double metal–semiconductor–metal transition and manipulation of the thermoelectric power factor. The maximum power factor (14 mW cm-1 K-2) is found for x ¼ 0.85, which corresponds to ZT z 0.2 at 300 K.

Synthesis, structural characterisation and thermoelectric properties of Bi1−xPbxOCuSe

The effect of Pb2+ doping on the structure and thermoelectric properties of BiOCuSe (also known as BiCuSeO or BiCuOSe) is described. With increasing Pb2+ content, the expansion of the unit cell results in a weakening of the bonding between the [Bi2(1-x) Pb2xO2]2(1-x)+ and the [Cu2Se2]2(1-x)- layers. The electrical resistivity and Seebeck coefficient decrease in a systematic way with growing Pb2+ levels. The thermal conductivity rises due to the increase of the electronic contribution with doping. The power factor of materials with a 4-5% Pb2+ content takes values of ca. 8 W cm-1 K-2 over a wide temperature range. ZT at 673 K is enhanced by ca. 50% when compared to values found for other dopants, such as Sr2+ or Mg2+.

Low-Frequency Noise in Field-Effect Devices Functionalized With Dendrimer/Carbon-Nanotube Multilayers

Low-frequency noise in an electrolyte-insulator- semiconductor (EIS) structure functionalized with multilayers of polyamidoamine (PAMAM) dendrimer and single-walled carbon nanotubes (SWNT) is studied. The noise spectral density exhibits 1/f(gamma) dependence with the power factor of gamma approximate to 0.8 and gamma = 0.8-1.8 for the bare and functionalized EIS sensor, respectively. The gate-voltage noise spectral density is practically independent of the pH value of the solution and increases with increasing gate voltage or gate-leakage current. It has been revealed that functionalization of an EIS structure with a PAMAM/SWNTs multilayer leads to an essential reduction of the 1/f noise. To interpret the noise behavior in bare and functionalized EIS devices, a gate-current noise model for capacitive EIS structures based on an equivalent flatband-voltage fluctuation concept has been developed.