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Protocolo ISO 11783: procedimentos para comunicação serial de dados do controlador de tarefa; ISO 11783 protocol: procedures for serial data communication with the task controller

Pereira, Robson Rogério Dutra
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/01/2009 Português
Relevância na Pesquisa
36.18%
O recente crescimento da utilização de tecnologias de automação e eletrônica embarcada em máquinas e implementos agrícolas tem estabelecido uma nova prática na área agrícola. Estas novas práticas relacionadas com a agricultura de precisão (AP) têm demandado a utilização de sensores e redes de comunicação embarcadas para aquisição de dados e controle dos dispositivos em campo. A incompatibilidade entre equipamentos e formatos de dados tornou-se um grande obstáculo. A tendência global é de uso de sistemas padronizados de acordo com a norma ISO 11783 (também conhecida como ISOBUS) nos dispositivos, ou Electronic Control Unit (ECU), utilizados na produção agrícola. No Brasil, essas ferramentas ainda não são largamente aplicadas. O objetivo deste trabalho é sistematizar as informações necessárias dos procedimentos para comunicação de uma ECU do implemento com a ECU de trator de gerenciamento. Focou-se no desenvolvimento dos arquivos padrões necessários e no programa da ECU do implemento, e testes de validação da comunicação dos dispositivos via rede ISO 11873. Estabeleceu-se a relação entre as informações sistematizadas e os dispositivos embarcados em máquinas agrícolas. Os dispositivos embarcados consistem em cinco ECUs interconectadas pela rede ISO 11783. Quatro ECUS estão localizados no tractor: ECU do GPS...

Critérios para seleção da arquitetura elétrica veicular em mercados emergentes.; Criteria for selection of vehicle electrical architectures for emerging markets.

Dal Poggetto, Gustavo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/07/2009 Português
Relevância na Pesquisa
46.18%
Este estudo tem por objetivo estabelecer os principais critérios de seleção de uma arquitetura elétrica adequada a mercados emergentes, considerando as necessidades de mercado, de legislação, de inovações e/ou novas funções a serem empregadas durante o ciclo de vida de um veículo. Para tanto, o resultado da pesquisa bibliográfica deste trabalho, apresentada na revisão teórica, primeiramente define o significado de arquitetura elétrica, e conta a sua evolução desde os primórdios da indústria automotiva até os dias de hoje, apontando quais são os principais sistemas elétricos existentes atualmente, deixando clara a fundamental importância da eletrônica embarcada na evolução do automóvel. Mostram, ainda, suas principais tendências tecnológicas, além de um descritivo sobre técnicas, critérios e metodologia de desenvolvimento de projetos de arquitetura elétrica empregados hoje na indústria. Na seqüência, o trabalho define os conceitos de mercado emergente e mercado desenvolvido, apontando suas particularidades, volumes de negócio (histórico e projetado), deixando evidente a importância dos mercados emergentes nos dias de hoje para a indústria automotiva mundial e a necessidade de se estabelecer estratégias específicas para estes mercados. Com base na própria pesquisa bibliográfica...

An aspect-oriented model-driven engineering approach for distributed embedded real-time systems; Uma abordagem de engenharia guiada por modelos para o projeto de sistemas tempo-real embarcados e distribuídos

Wehrmeister, Marco Aurélio
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
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Atualmente, o projeto de sistemas tempo-real embarcados e distribuídos está crescendo em complexidade devido à sua natureza heterogênea e ao crescente número e diversidade de funções que um único sistema desempenha. Sistemas de automação industrial, sistemas eletrônicos em automóveis e veículos aéreos, equipamentos médicos, entre outros, são exemplos de tais sistemas. Tais sistemas são compostos por componentes distintos (blocos de hardware e software), os quais geralmente são projetados concorrentemente utilizando modelos, ferramentas e linguagens de especificação e implementação diferentes. Além disso, estes sistemas tem requisitos específicos e importantes, os quais não representam (por si só) as funcionalidades esperadas do sistema, mas podem afetar a forma como o sistema executa suas funcionalidades e são muito importantes para a realização do projeto com sucesso. Os chamados requisitos não-funcionais são difíceis de tratar durante todo o ciclo de projeto porque normalmente um único requisito não-funcional afeta vários componentes diferentes. A presente tese de doutorado propõe a integração automatizada das fases de projeto de sistemas tempo-real embarcados e distribuídos focando em aplicações na área da automação. A abordagem proposta usa técnicas de engenharia guiada por modelos (do inglês Model Driven Engineering ou MDE) e projeto orientado a aspectos (do inglês Aspect-Oriented Design ou AOD) juntamente com o uso de plataformas previamente desenvolvidas (ou desenvolvida por terceiros) para projetar os componentes de sistemas tempo-real embarcados e distribuídos. Adicionalmente...

Sistema embarcado para a manutenção inteligente de atuadores elétricos; Embedded systems for intelligent maintenance of electrical actuators

Bosa, Jefferson Luiz
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
36.2%
O elevado custo de manutenção nos ambientes industriais motivou pesquisas de novas técnicas para melhorar as ações de reparos. Com a evolução tecnológica, principalmente da eletrônica, que proporcionou o uso de sistemas embarcados para melhorar as atividades de manutenção, estas agregaram inteligência e evoluíram para uma manutenção pró-ativa. Através de ferramentas de processamento de sinais, inteligência artificial e tolerância a falhas, surgiram novas abordagens para os sistemas de monitoramento a serviço da equipe de manutenção. Os ditos sistemas de manutenção inteligente, cuja tarefa é realizar testes em funcionamento (on-line) nos equipamentos industriais, promovem novos modelos de confiabilidade e disponibilidade. Tais sistemas são baseados nos conceitos de tolerância a falhas, e visam detectar, diagnosticar e predizer a ocorrência de falhas. Deste modo, fornece-se aos engenheiros de manutenção a informação antecipada do estado de comportamento do equipamento antes mesmo deste manifestar uma falha, reduzindo custos, aumentando a vida útil e tornando previsível o reparo. Para o desenvolvimento do sistema de manutenção inteligente objeto deste trabalho, foram estudadas técnicas de inteligência artificial (redes neurais artificiais)...

Java applets for a WWW-HTML-based course in power electronics

Gonçalves, F. A S; Canesin, C. A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 85-90
Português
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This paper introduces Java applet programs for a WWW (world wide web)-HTML (hypertext markup language)-based multimedia course in Power Electronics. The applet programs were developed with the purpose of providing an interactive visual simulation and analysis of idealized uncontrolled single-phase, and three-phase rectifiers. In addition, this paper discusses the development and utilization of JAVA applet programs to solve some design-oriented equations for rectifier applications. The major goal of these proposed JAVA applets was to provide more facilities for the students increase their pace in Power Electronics course, emphasizing waveforms analysis, and providing conditions for an on-line comparative analysis among different hands-on laboratory experiences, via a normal Internet TCP/IP connection. Therefore, using the proposed JAVA applets, which were embedded in a WWW-HTML-based course in Power Electronics, was observed an important improvement of the apprenticeship for the content of this course. Therefore, the course structure becomes fluid, allowing a true on-line course over the WWW, motivating students to learn its content, and apply it in some applications-oriented projects, and their home-works.

Physical principles for scalable neural recording

Marblestone, Adam H.; Zamft, Bradley M.; Maguire, Yael G.; Shapiro, Mikhail G.; Cybulski, Thaddeus R.; Glaser, Joshua I.; Amodei, Dario; Stranges, P. Benjamin; Kalhor, Reza; Dalrymple, David A.; Seo, Dongjin; Alon, Elad; Maharbiz, Michel M.; Carmena, Jose
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.13%
Simultaneously measuring the activities of all neurons in a mammalian brain at millisecond resolution is a challenge beyond the limits of existing techniques in neuroscience. Entirely new approaches may be required, motivating an analysis of the fundamental physical constraints on the problem. We outline the physical principles governing brain activity mapping using optical, electrical, magnetic resonance, and molecular modalities of neural recording. Focusing on the mouse brain, we analyze the scalability of each method, concentrating on the limitations imposed by spatiotemporal resolution, energy dissipation, and volume displacement. Based on this analysis, all existing approaches require orders of magnitude improvement in key parameters. Electrical recording is limited by the low multiplexing capacity of electrodes and their lack of intrinsic spatial resolution, optical methods are constrained by the scattering of visible light in brain tissue, magnetic resonance is hindered by the diffusion and relaxation timescales of water protons, and the implementation of molecular recording is complicated by the stochastic kinetics of enzymes. Understanding the physical limits of brain activity mapping may provide insight into opportunities for novel solutions. For example...

Sustainable embedded software lifecycle planning

Lee, Dong-Hyun; In, Hoh Peter; Lee, Keun; Park, Sooyong; Hinchey, Mike
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: info:eu-repo/semantics/article; all_ul_research; ul_published_reviewed
Português
Relevância na Pesquisa
36.2%
peer-reviewed; Time-to-market is a crucial factor in increasing market share in the consumer electronics (CE) market. Furthermore, fierce competition in the market tends to sharply lower the prices of brand-new CE products as soon as they are released. Software-intensive embedded system design methods such as hardware/software co-design have been studied with the goal of reducing development lead-time by designing hardware and software simultaneously. Many researchers, however, concentrate on static design methods—in which design remains unchanged once determined. To survive this deadly market competition, a dynamic design strategy that takes various market conditions into account is needed for software-intensive embedded systems. In this paper, a sustainable embedded software lifecycle planning (SESLIP) process based on the evolution of embedded software is proposed. The SESLIP process provides a dynamic method for both selecting product lifecycle design alternatives and generating a profit-maximizing transition plan that covers the entire lifecycle of a product

Optimum wireless power transmission for sensors embedded in concrete

Jiang, Shan
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.2%
Various nondestructive testing (NDT) technologies for construction and performance monitoring have been studied for decades. Recently, the rapid evolution of wireless sensor network (WSN) technologies has enabled the development of sensors that can be embedded in concrete to monitor the structural health of infrastructure. Such sensors can be buried inside concrete and they can collect and report valuable volumetric data related to the health of a structure during and/or after construction. Wireless embedded sensors monitoring system is also a promising solution for decreasing the high installation and maintenance cost of the conventional wire based monitoring systems. Wireless monitoring sensors need to operate for long time. However, sensor batteries have finite life-time. Therefore, in order to enable long operational life of wireless sensors, novel wireless powering methods, which can charge the sensors’ rechargeable batteries wirelessly, need to be developed. ^ The optimization of RF wireless powering of sensors embedded in concrete is studied here. First, our analytical results focus on calculating the transmission loss and propagation loss of electromagnetic waves penetrating into plain concrete at different humidity conditions for various frequencies. This analysis specifically leads to the identification of an optimum frequency range within 20–80 MHz that is validated through full-wave electromagnetic simulations. Second...

FPGA-based embedded system for ultrasonic positioning

Sánchez, Alberto; Castro, Ángel de; González-de-Rivera, Guillermo; Garrido, Javier
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: conferenceObject; bookPart
Português
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Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. A. Sánchez, Á. de Castro, G. Gonzalez-de-Rivera, and J. Garrido, "FPGA-based embedded system for ultrasonic positioning", 2010 IEEE International Symposium on Industrial Electronics, ISIE, Bari (Italy), 2010, pp. 3051 - 3056; This paper presents an FPGA-based ultrasonic location system. This system uses low-cost FPGAs and ultrasonic transducers to provide 3-D location to mobile nodes in an indoor environment. Synchronization is reached using the radiofrequency transducers that mobile nodes usually include. FPGAs have been used to sample ultrasonics and radiofrequency inside a custom peripheral which is attached to a MicroBlaze soft-processor. The calculus of the position of the mobile node is accomplished inside this processor.

New embedded digital front-end for high resolution PET scanner

Guerra, P.; Espinosa, J.; Ortuño, Juan E.; Kontaxakis, G.; Vaquero, Juan José; Desco, Manuel; Santos, Andrés
Fonte: Institute of Electrical and Electronics Engineers (IEEE) Publicador: Institute of Electrical and Electronics Engineers (IEEE)
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article Formato: application/pdf
Publicado em //2006 Português
Relevância na Pesquisa
46.12%
This work describes a new digital front-end for a high-resolution low-cost animal PET scanner which is currently under development. The advances in flexibility and size of modern FPGAs together with the release of new tools enable the integration of most of the front-end electronics in a single FPGA. The implemented system includes a small 32-bit RISC processor, several peripherals attached to the internal buses and a special DSP unit closely attached to the processor which is dedicated to the detection of the gamma events. On top of these, a small footprint real time operating system abstracts the underlying hardware, providing the mechanisms to combine on-chip slow control and data streaming; This work was supported in part by the FPU Research Grant from the Spanish Education and Science Ministry, by the Spanish Thematic Network IM3 (PI052204) and project TEC2004-07052-C02-02

Diagnosis of embedded software using program spectra

Zoeteweij, Peter; Abreu, Rui; Golsteijn, Rob; Van Gemund, Arjan JC
Fonte: IEEE Publicador: IEEE
Tipo: Conferência ou Objeto de Conferência
Publicado em //2007 Português
Relevância na Pesquisa
36.26%
Automated diagnosis of errors detected during software testing can improve the efficiency of the debugging process, and can thus help to make software more reliable. In this paper we discuss the application of a specific automated debugging technique, namely software fault localization through the analysis of program spectra, in the area of embedded software in high-volume consumer electronics products. We discuss why the technique is particularly well suited for this application domain, and through experiments on an industrial test case we demonstrate that it can lead to highly accurate diagnoses of realistic errors.

Experimental and analytical evalution of embedded link performance with small-scale channel fluctuations

Camp, Joseph D.
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: application/pdf
Português
Relevância na Pesquisa
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We have deployed a first-of-its-kind, urban-scale wireless mesh network which provides Internet access to 1000's of users spanning multiple square kilometers in an underserved area in Houston, TX. However, in this and other urban environments, IEEE 802.11 link performance is both misunderstood and poor-performing due to complex node interactions which are affected by a vast array of factors including topology, channel conditions, modulation rate, packet sizes, and physical layer capture. In this thesis, I draw from 100's of thousands of urban measurements and develop an analytical model to understand the performance of links embedded in the aforementioned complex scenarios. My focus is on two fundamental concepts involving embedded links. First, choosing the modulation rate which maximizes the throughput is imperative since each bit of the (overly-)shared medium is critical. Yet, all existing rate adaptation mechanisrns fail to track the ideal rate even in a simple, non-mobile urban scenario. Using a custom cross-layer framework, I implement multiple and previously un-implemented rate adaptation mechanisms to reveal the reasons for the failure and design rate adaptation mechanisms which are able to track urban and downtown vehicular and non-mobile environments. Second...

Embedded heat pipes in cofired ceramic substrates for enhanced thermal management of electronics

Zampino, Marc Anthony
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.18%
A novel and new thermal management technology for advanced ceramic microelectronic packages has been developed incorporating miniature heat pipes embedded in the ceramic substrate. The heat pipes use an axially grooved wick structure and water as the working fluid. Prototype substrate/heat pipe systems were fabricated using high temperature co-fired ceramic (alumina). The heat pipes were nominally 81 mm in length, 10 mm in width, and 4 mm in height, and were charged with approximately 50–80 μL of water. Platinum thick film heaters were fabricated on the surface of the substrate to simulate heat dissipating electronic components. Several thermocouples were affixed to the substrate to monitor temperature. One end of the substrate was affixed to a heat sink maintained at constant temperature. The prototypes were tested and shown to successful and reliably operate with thermal loads over 20 Watts, with thermal input from single and multiple sources along the surface of the substrate. Temperature distributions are discussed for the various configurations and the effective thermal resistance of the substrate/heat pipe system is calculated. Finite element analysis was used to support the experimental findings and better understand the sources of the system's thermal resistance. ^

In-Flight Collision Avoidance Controller Based Only on OS4 Embedded Sensors

Becker, Marcelo; Sampaio, Rafael Coronel Bueno; Bouabdallah, Samir; de Perrot, Vincent; Siegwart, Roland
Fonte: ABCM BRAZILIAN SOC MECHANICAL SCIENCES & ENGINEERING; Rio de Janeiro, RJ Publicador: ABCM BRAZILIAN SOC MECHANICAL SCIENCES & ENGINEERING; Rio de Janeiro, RJ
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.18%
The major goal of this research was the development and implementation of a control system able to avoid collisions during the flight for a mini-quadrotor helicopter, based only on its embedded sensors without changing the environment. However, it is important to highlight that the design aspects must be seriously considered in order to overcome hardware limitations and achieve control simplification. The controllers of a UAV (Unmanned Aerial Vehicle) robot deal with highly unstable dynamics and strong axes coupling. Furthermore, any additional embedded sensor increases the robot total weight and therefore, decreases its operating time. The best balance between embedded electronics and robot operating time is desired. This paper focuses not only on the development and implementation of a collision avoidance controller for a mini-robotic helicopter using only its embedded sensors, but also on the mathematical model that was essential for the controller developing phases. Based on this model we carried out the development of a simulation tool based on MatLab/Simulink that was fundamental for setting the controllers' parameters. This tool allowed us to simulate and improve the OS4 controllers in different modeled environments and test different approaches. After that...

In-flight collision avoidance controller based only on OS4 embedded sensors

Becker,Marcelo; Sampaio,Rafael Coronel B.; Bouabdallah,Samir; Perrot,Vincent de; Siegwart,Roland
Fonte: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM Publicador: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 Português
Relevância na Pesquisa
36.18%
The major goal of this research was the development and implementation of a control system able to avoid collisions during the flight for a mini-quadrotor helicopter, based only on its embedded sensors without changing the environment. However, it is important to highlight that the design aspects must be seriously considered in order to overcome hardware limitations and achieve control simplification. The controllers of a UAV (Unmanned Aerial Vehicle) robot deal with highly unstable dynamics and strong axes coupling. Furthermore, any additional embedded sensor increases the robot total weight and therefore, decreases its operating time. The best balance between embedded electronics and robot operating time is desired. This paper focuses not only on the development and implementation of a collision avoidance controller for a mini-robotic helicopter using only its embedded sensors, but also on the mathematical model that was essential for the controller developing phases. Based on this model we carried out the development of a simulation tool based on MatLab/Simulink that was fundamental for setting the controllers' parameters. This tool allowed us to simulate and improve the OS4 controllers in different modeled environments and test different approaches. After that...

A Constructivist Approach for Teaching Embedded Systems

Ordinez, Leonardo Damian; Alimenti, Omar Ruben
Fonte: Ieee-inst Electrical Electronics Engineers Inc Publicador: Ieee-inst Electrical Electronics Engineers Inc
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Português
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46.13%
Due to the technological breakthrough of recent years, electronic devices have become an important part of everyday life. Most of these devices falls within the class of systems called embedded systems. This article presents a proposal for a course on embedded systems. The proposal is based on a
constructivist approach to teaching, with particular emphasis on problem-based learning.; Fil: Ordinez, Leonardo Damian. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Bahia Blanca. Instituto de Invest.en Ing.Electrica; Argentina;; Fil: Alimenti, Omar Ruben. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Bahia Blanca. Instituto de Invest.en Ing.Electrica; Argentina;

Virtual embedded blocks: A methodology for evaluating embedded elements in FPGAs

Ho, C. H.; Leong, P. H W; Luk, W.; Wilton, S. J E; López-Buedo, Sergio
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: conferenceObject; bookPart
Português
Relevância na Pesquisa
36.22%
Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. C. H. Ho, P. H. W. Leong, W. Luk, S. J. E. Wilton, and S. Buedo, "Virtual embedded blocks: A methodology for evaluating embedded elements in FPGAs", in 14th Annual IEEE Symposium on Field-Programmable Custom Computing Machines, 2006. FCCM '06. 35-44; Embedded elements, such as block multipliers, are increasingly used in advanced field programmable gate array (FPGA) devices to improve efficiency in speed, area and power consumption. A methodology is described for assessing the impact of such embedded elements on efficiency. The methodology involves creating dummy elements, called virtual embedded blocks (VEBs), in the FPGA to model the size, position and delay of the embedded elements. The standard design flow offered by FPGA and CAD vendors can be used for mapping, placement, routing and retiming of designs with VEBs. The speed and resource utilisation of the resulting designs can then be inferred using the FPGA vendor's timing analysis tools. We illustrate the application of this methodology to the evaluation of various schemes of involving embedded elements that support floating-point computations

An Embedded 12-bit 80MS/s A/D/A Interface for Power-Line Communications in 0.13μm Pure Digital CMOS Technology

Delgado-Restituto, Manuel; Ruiz Amaya, Jesús; Rosa, José M. de la; Fernández-Bootello, Juan Francisco; Díez, Leila; Río, Rocío del; Rodríguez-Vázquez, Ángel
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: Artículo Formato: 463351 bytes; application/pdf
Português
Relevância na Pesquisa
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This paper presents an embedded interface, comprising both A/D and D/A converters, which has been implemented in a 0.13μm pure digital CMOS technology. The interface is integrated in a system for high-performance broad-band power-line communications. The A/D converter uses a pipelined structure, whereas the D/A stage is based on segmented current steering techniques. In both cases, specifications are 12-b resolution at 80MS/s and MTPR above 56dB.; This work has been partially funded by the European MEDEA+ Office under Project MIDAS-A110.; Peer reviewed

HW-SW components for parallel embedded computing on NoC-based MPSoCs

Joven Murillo, Jaume
Fonte: Bellaterra: Universitat Autònoma de Barcelona, Publicador: Bellaterra: Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2010 Português
Relevância na Pesquisa
36.13%
Descripció del recurs: el 1 de febrer de 2011; Recentment, en el camp del sistemes encastats, estem assistint al creixement de sistemes Multi-Processor System-on-Chip (MPSoC). El paradigma de Network-on-chip (NoC) s'ha proposat una solució viable, eficient, escalable, predictible i flexible per connectar components dins un xip, o inclús sistemes complets basats en busos dins al xip amb la finalitat de crear sistemes altament complexos. Així, el paradigma de computació encastada d'altres prestacions està arribant a través d'integrar hardware altament paral·lel amb llibreries software per obtenir una màxima integració a nivell de plataforma utilitzant de components prèviament dissenyats (IP cores), en la forma de arquitectures NoC-based MPSoCs. No obstant, quan el nombre de components augmenta hi ha diversos desafiaments i problemes a resoldre. El primer repte és el disseny d'una xarxa d'interconnexió que proporcioni qualitat de servei assegurant un cert ample de banda i latència entre cada bloc del sistema, amb el mínim area i consum possible. Ja que l'espai de disseny en arquitectures NoCs és enorme, s'han de desenvolupar entorns de simulació, i verificació per explorar validar i optimitzar múltiples NoC arquitectures. El segon objectiu...

Scratchpad-oriented address generation for low-power embedded VLIW processors

Talavera Velilla, Guillermo
Fonte: Bellaterra: Universitat Autònoma de Barcelona, Publicador: Bellaterra: Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2010 Português
Relevância na Pesquisa
36.18%
Descripció del recurs: el 10 de febrer de 2011; Actualmente, los sistemas encastados están creciendo a un ritmo impresionante y proporcionan cada vez aplicaciones más sofisticadas. Un conjunto de creciente importancia son los sistemas multimedia portátiles de tiempo real y los sistemas de comunicación de procesado digital de señal: teléfonos móviles, PDAs, cámaras digitales, consolas portátiles de juegos, terminales multimedia, netbooks, etc. Estos sistemas requieren computación específica de alto rendimiento, generalmente con restricciones de tiempo real y calidad de servicio (Quality of Service - QoS), que han de ejecutarse con un nivel bajo de consumo para extender la vida de la batería y evitar el calentamiento del dispositivo. También se requiere una arquitectura flexible para satisfacer las restricciones del "time-to-market". En consecuencia, los sistemas encastados necesitan una solución programable, de bajo consumo y alta capacidad de computación para satisfacer todos los requerimientos. Las arquitecturas de tipo Very Long Instruction Word parecen una buena solución ya que proporcionan el suficiente rendimiento a bajo consumo con la programabilidad requerida. Estas arquitecturas se asientan sobre el esfuerzo del compilador para extraer el paralelismo disponible a nivel datos y de instrucciones para mantener las unidades computacionales ocupadas todo el rato. Con la densidad de los transistores doblando cada 18 meses...