Hybrid Linux System Modeling with Mixed-Level Simulation

Dissertação de mestrado integrado em Engenharia Electrónica Industrial e ComputadoresWe live in a world where the need for computer-based systems with better performances is growing fast, and part of these systems are embedded systems. This kind of systems are everywhere around us, and we use them everyday even without noticing. Nevertheless, there are issues related to embedded systems in what comes to real-time requirements, because the failure of such systems can be harmful to the user or its environment. For this reason, a common technique to meet real-time requirements in difficult scenarios is accelerating software applications by using parallelization techniques and dedicated hardware components. This dissertations’ goal is to adopt a methodology of hardware-software co-design aided by co-simulation, making the design flow more efficient and reliable. An isolated validation does not guarantee integral system functionality, but the use of an integrated co-simulation environment allows detecting system problems before moving to the physical implementation. In this dissertation, an integrated co-simulation environment will be developed, using the Quick EMUlator (QEMU) as a tool for emulating embedded software platforms in a Linux-based environment. A SystemVerilog Direct Programming Interface (DPI) Library was developed in order to allow SystemVerilog simulators that support DPI to perform co-simulation with QEMU. A library for DLL blocks was also developed in order to allow PSIMR to communicate with QEMU. Together with QEMU, these libraries open up the possibility to co-simulate several parts of a system that includes power electronics and hardware acceleration together with an emulated embedded platform. In order to validate the functionality of the developed co-simulation environment, a demonstration application scenario was developed following a design flow that takes advantage of the mentioned simulation environment capabilities.Vivemos num mundo em que a procura por sistemas computer-based com desempenhos cada vez melhores domina o mercado. Estamos rodeados por este tipo de sistemas, usando-os todos os dias sem nos apercebermos disso, sendo grande parte deles sistemas embebidos. Ainda assim, existem problemas relacionados com os sistemas embebidos no que toca aos requisitos de tempo-real, porque uma falha destes sistemas pode ser perigosa para o utilizador ou o ambiente que o rodeia. Devido a isto, uma técnica comum para se conseguir cumprir os requisitos de tempo-real em aplicações críticas é a aceleração de aplicações de software, utilizando técnicas de paralelização e o uso de componentes de hardware dedicados. O objetivo desta dissertação é adotar uma metodologia de co-design de hardwaresoftware apoiada em co-simulação, tornando o design flow mais eficiente e fiável. Uma validação isolada não garante a funcionalidade do sistema completo, mas a utilização de um ambiente de co-simulação permite detetar problemas no sistema antes deste ser implementado na plataforma alvo. Nesta dissertação será desenvolvido um ambiente de co-simulação usando o QEMU como emulador para as plataformas de software "embebido" baseadas em Linux. Uma biblioteca para SystemVerilog DPI foi desenvolvida, que permite a co-simulação entre o QEMU e simuladores de Register-Transfer Level (RTL) que suportem SystemVerilog. Foi também desenvolvida uma biblioteca para os blocos Dynamic Link Library (DLL) do PSIMR , de modo a permitir a ligação ao QEMU. Em conjunto, as bibliotecas desenvolvidas permitem a co-simulação de diversas partes do sistema, nomeadamente do hardware de eletrónica de potência e dos aceleradores de hardware, juntamente com a plataforma embebida emulada no QEMU.Para validar as funcionalidades do ambiente de co-simulação desenvolvido, foi explorado um cenário de aplicação que tem por base esse mesmo ambiente

INTEGRAÇÃO DE SISTEMAS FOTOVOLTAICOS E AQUECEDORES DE ÁGUA SOLAR EM TELHADOS RESIDENCIAIS

O aumento da demanda de energia elétrica no Brasil para os próximos 10 anos é de 4,25% ao ano, demandando assim uma expansão do sistema de 3,8% a.a., com previsão de crescimento médio da carga de energia de 2.900 MW ano-1. O aumento da demanda, somado aos recorrentes déficits hídricos em várias usinas hidrelétricas e a lentidão da expansão do sistema de geração sustentável, acarretará aumento do consumo de energia gerada por meio de combustíveis fósseis. Neste contexto, a implantação de sistemas híbridos (energia elétrica fotovoltaica e aquecedor de água solar) integrados a rede de distribuição de energia elétrica, apresenta-se como uma alternativa para reduzir essa demanda, com um potencial de produção média de cerca de 3.000 MWh mês-1 a cada 10 mil casas, que corresponde a energia produzida por uma pequena central hidrelétrica de 6 MW (FC = 0,7) de capacidade instalada.Palavras-chave: energia solar, aquecimento de água, matriz energética.  INTEGRATION OF PHOTOVOLTAIC SYSTEMS AND WATER HEATER SOLAR ROOFS IN RESIDENTIAL ABSTRACTThe increase in electric energy demand in Brazil for the next 10 years is 4.25% per year, thus requiring an expansion of the system of 3.8% per year, with an expected average energy load growth of 2,900 MW year-1. The increase in demand coupled with the recurring water deficits in several hydroelectric plants and the slow expansion of the sustainable generation system will increase the consumption of energy generated by fossil. In this context, the deployment of hybrid systems (photovoltaic electricity and solar water heater) integrated electrical power distribution network, presents itself as an alternative to reduce this demand, with an average production potential of about 3,000 MWh month-1 every 10,000 homes, equivalent to the energy produced by a small hydroelectric power plant of 6 MW (FC = 0,7) of installed capacity.Keywords: solar energy, water heating, energy matrix. DOI: http://dx.doi.org/10.5935/2318-7670.v05n03a0

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

A century of trends in adult human height

International audienc

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions