Exploration of the power-performance tradeoff through parameterization of FPGA-based multiprocessor systems

The design space of FPGA-based processor systems is huge, because many parameters can be modified at design- and runtime to achieve an efficient system solution in terms of performance, power and energy consumption. Such parameters are, for example, the number of processors and their configurations, the clock frequencies at design time, the use of dynamic frequency scaling at runtime, the application task distribution, and the FPGA type and size. The major contribution of this paper is the exploration of all these parameters and their impact on performance, power dissipation, and energy consumption for four different application scenarios. The goal is to introduce a first approach for a developer's guideline, supporting the choice of an optimized and specific system parameterization for a target application on FPGA-based multiprocessor systems-on-chip. The FPGAs used for these explorations were Xilinx Virtex-4 and Xilinx Virtex-5. The performance results were measured on the FPGA while the power consumption was estimated using the Xilinx X Power Analyzer tool. Finally, a novel runtime adaptive multiprocessor architecture for dynamic clock frequency scaling is introduced and used for the performance, power and energy consumption evaluations

Development of a robotic hand using bioinspired optimization for mechanical and control design : UnB-hand

For the last four decades, the development of robotic hands has been the focus of several works. However, a small part of those approaches consider the exploitation of parallelism of FPGA-based (Field Programmable Gate Arrays) systems or discuss how using bioinspired optimization algorithms could improve the mechanical and controller components. This work considers developing a bioinspired robotic hand that achieves motion and force control with a logic hardware architecture implemented in FPGA intended to be replicated and executed with suitable parallelism, fitting a single device. The developed robotic hand prototype has five fingers and seven DoF (Degrees of Freedom). Using bioinspired optimization, such as PSO (Particle Swarm Optimization), both the rigid finger mechanism and the impedance controller were optimized and incorporated the results in several practical grasping experiments. The validation of this work is done with the Cutkosky grasping taxonomy and some grasping experiments with interference. The tests proved the proficiency of this works for a wide range of power and some precision grasp. The reader can see the experiments in the attached videos

Architectural specification, exploration and simulation through rewriting-logic

In recent years Arvind’s Group at MIT has shown the usefulness of term rewriting theory for the specification of processor architectures. In their approach processors specified by term rewriting systems are translated into a standard hardware description language for simulation purposes.Keywords: Rewriting-logic, High Level Specification and Simulation, Design Environment.&nbsp

Pilares provisionales prototipados como alternativa a los pilares provisionales de poliéter éter-cetona

Una etapa muy importante en el proceso de rehabilitación oral de los pacientes con implantes dentales es la provisionalización, la cual da una idea de la futura restauración y permite la creación del perfil de emergencia de la encía, pero también da al paciente la oportunidad de tener una solución estética y funcional hasta el final cuando se fabrican las prótesis definitivas. Para soportar la restauración provisional, se utilizan pilares provisionales; estos pueden ser metálicos o poliméricos. Actualmente, la mayoría de las empresas productoras de implantes suministran pilares provisionales de Poliéter éter-cetona (PEEK), un material estético con buenas propiedades mecánicas, pero con escasa adherencia al polimetilmetacrilato (PMMA). Considerando que el PMMA es el material más utilizado para la fabricación de coronas provisionales, pero su adherencia con los pilares actuales no es la mejor, se han realizado diferentes investigaciones para mejorar esta unión. Este trabajo propone el uso de pilares provisionales fabricados mediante impresión 3D a partir de una resina de fotopolimerización, que ya ha tenido otras aplicaciones en el campo dental. Las propiedades mecánicas de los pilares de PEEK prefabricados se compararon con los pilares obtenidos por impresión 3D, encontrándose que, en las pruebas de comprensión, los pilares de PEEK se comportaron mejor con una diferencia estadísticamente significativa; no se encontraron diferencias significativas en las pruebas de flexión; mientras que en las pruebas de adherencia los pilares de resina tuvieron un mejor comportamiento, siendo la diferencia estadísticamente significativa

A methodology to design a domotics human-machine interface for visually impaired people

According to the World Health Organization (WHO), more than one billion people in the world have some disability. A 2017 report of the Brazilian Geography and Statistics Institute (IBGE) shows that 45.6 million Brazilians have an impairment, among which 18.8 million declare vision issues not fixed by glasses or contact lenses. So, a significant population leads to developing many legal mechanisms to guarantee their quality-of-life. Potentially, these mechanisms should regulate many aspects of urban design to assure the accessibility of any environment. However, there are several design challenges to be overcome. In this paper, we address the problem of developing Human-Machine Interfaces (HMI) for visually impaired people, focusing on residential automation systems (domotics). The efficient development of such interfaces needs a link among two accessibility areas: domotics and HMI. We used pre-tests, human-computer interaction (HCI) techniques, and the user's emotional state identification to determine the user's profile. We must highlight that the design is intended to be used by any user, visually impaired or not. That is, the system should be universal. The methodology described can be used to assess the efficiency and quality metrics of accessibility in domotics systems

O processo de desenvolvimento de produtos de um projeto realizado por equipes virtuais para construir um ventilador pulmonar de baixo custo no contexto do COVID-19 / The product development process of a virtual team project to build a low-cost lung ventilator in the context of COVID-19

Os projetos colaborativos entre governo, universidade e empresa privada desempenham um importante papel no gerenciamento de crises, além de serem fundamentais para a implementação de estratégias de inovação. A partir das necessidades geradas pela crise de saúde pública advindas com a Covid-19, este trabalho apresenta uma análise do diagnóstico do processo de desenvolvimento de produto (PDP) de um ventilador pulmonar de baixo custo, desenvolvido em parceria entre pesquisadores da Universidade de Brasília (UNB), da Universidade Federal de São Carlos (UFSCAR), do Instituto Federal de Brasília (IFB), e da Escola Superior de Ciências da Saúde (ESCS). O projeto foi financiado pela Fundação de Apoio à Pesquisa do Distrito Federal, é gerenciado financeiramente pela Fundação de apoio da UNB, e tem parceria com uma empresa privada, com o foco em transferir tecnologia e na produção em escala do equipamento. O diagnóstico do PDP foi realizado a partir da associação de dois modelos amplamente difundidos na literatura, apresentando características peculiares de um projeto materializado em ambiente universitário, com prazos curtos, e atividades desenvolvidas, em grande parte, remotamente. Os resultados apresentados comprovaram uma estrutura similar a projetos do tipo mecatrônico, e com uma alta interação entre os atores do projeto na realização das atividades

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Desarrollo de una matriz polimérica obtenida por la técnica de electrospinning para regeneración ósea.

Los accidentes de tránsito en Colombia presentan una gran prevalencia y las estadísticas del instituto colombiano de Medicina Legal muestran una tendencia a conservarse así. Una de las zonas anatómicas más afectadas en un accidente de tránsito es el complejo cráneo facial. Los huesos del cráneo y de la cara a menudo presentan problemas para regenerarse, siendo necesario recurrir a técnicas reconstructivas y en el caso del cráneo, a elementos como las mallas y láminas de titanio que aunque logran sellar la cavidad, son incapaces de estimular la regeneración ósea y elevan notablemente los costos del tratamiento. Los defectos óseos de gran tamaño se comportan como “críticos”, y son incapaces de cicatrizar espontáneamente, siendo necesario la utilización de injertos o sustitutos óseos para estimular la iniciación y desarrollo del proceso regenerativo. También son considerados defectos de tamaño crítico las cavidades que permanecen como consecuencia de la extirpación quirúrgica de lesiones intraóseas como tumores, quistes, osteomielitis, etc., y las pérdidas fisiológicas de los rebordes alveolares en la cavidad oral. Los materiales de elección para injerto, son en primer lugar el hueso del propio paciente (autoinjerto), y como segunda opción los aloinjertos, provenientes de un banco de hueso, o los xenoinjertos, que tienen su origen en otras especies. El desarrollo científico, con la aparición de la Ingeniería de Tejidos, ha permitido una tercera opción que son los aloplásticos, materiales sintéticos capaces de servir como soporte al desarrollo tisular. De la gran variedad de materiales utilizados, los polímeros por sus propiedades físicas, químicas y biológicas, son los mejores candidatos para la elaboración de matrices, con las cuales se busca estimular el proceso regenerativo y reparar el tejido dañado mediante la incorporación de células del mismo organismo

Comparative analysis of simulation and experiment for the Hall-type thruster BPT-4000

Since 2004, the Plasma Physics Laboratory (PPL/PI/UnB) has been developing permanent magnet Hall thrusters due to their high efficiency. However, permanent magnets have limited use due to their maximum working temperature (the point at which they begin to demagnetize). Therefore, strict control of the temperature of the magnets must be carried out. In the present work we perform a numerical thermal simulation of a Hall thruster taken from the literature (e.g., the BPT-4000) and compare the obtained simulated thruster temperatures with experimental values taken in the laboratory. This work aims to verify the reliability of our simulation strategy in order to simulate other Hall-type thrusters in the future. The obtained simulation data was consistent with experimental results, demonstrating that the used simulation tool is reliable. In the future we will use this strategy for the simulation of improved plasma Hall thrusters developed at PPL aiming at improving its engineering model in order to prepare for future space qualification tests

Elaboración y caracterización biomecánica de pilares provisionales anatómicos mediante un tipo de prototipeado con ácido poliláctico.

El manejo de pacientes parcialmente edéntulos con implantes dentales es una opción ideal actualmente, pero está restringida debido a su alto costo. Para realizar una restauración definitiva se necesita de varios aditamentos, uno de ellos son los pilares provisionales, existen en el mercado varias casas comerciales que los ofrecen de diferentes materiales, pero todos con un elevado costo. El objetivo de esta investigación fue desarrollar y caracterizar pilares provisionales anatómicos fabricados en impresión 3D con ácido poliláctico y resina fotopolimerizable. Materiales y métodos: Se diseñaron pilares anatómicos temporales y se obtuvieron por impresión 3D en PLA y Resina fotopolimerica, estos fueron sometidos a pruebas de biocompatibilidad, caracterización biomecánica y pruebas de adhesión