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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
461

Exploring the biocybernetic loop : classifying psychophysiological responses to cultural artefacts using physiological computing

Karran, Alexander John January 2014 (has links)
The aim of this research project was to provide a bio-sensing component for a real-time adaptive technology in the context of cultural heritage. The proposed system was designed to infer the interest or intention of the user and to augment elements of the cultural heritage experience interactively through implicit interaction. Implicit interaction in this context is the process whereby the system observes the user while they interact with artefacts; recording psychophysiological responses to cultural heritage artefacts or materials and acting upon these responses to drive adaptations in content in real-time. Real-time biocybernetic control is the central component of physiological computing wherein physiological data are converted into a control input for a technological system. At its core the bio-sensing component is a biocybernetic control loop that utilises an inference of user interest as its primary driver. A biocybernetic loop is composed of four main stages: inference, classification, adaptation and interaction. The programme of research described in this thesis is concerned primarily with exploration of the inference and classification elements of the biocybernetic loop but also encompasses an element of adaptation and interaction. These elements are explored first through literature review and discussion (presented in chapters 1-5) and then through experimental studies (presented in chapters 7-11).
462

Asymmetric Multiprocessing Real Time Operating System on Multicore Platforms

January 2014 (has links)
abstract: The need for multi-core architectural trends was realized in the desktop computing domain fairly long back. This trend is also beginning to be seen in the deeply embedded systems such as automotive and avionics industry owing to ever increasing demands in terms of sheer computational bandwidth, responsiveness, reliability and power consumption constraints. The adoption of such multi-core architectures in safety critical systems is often met with resistance owing to the overhead in migration of the existing stable code base to the new system setup, typically requiring extensive re-design. This also brings about the need for exhaustive testing and validation that goes hand in hand with such a migration, especially in safety critical real-time systems. This project highlights the steps to develop an asymmetric multiprocessing variant of Micrium µC/OS-II real-time operating system suited for a multi-core system. This RTOS variant also supports multi-core synchronization, shared memory management and multi-core messaging queues. Since such specialized embedded systems are usually developed by system designers focused more so on the functionality than on the coding standards, the adoption of automatic production code generation tools, such as SIMULINK's Embedded Coder, is increasingly becoming the industry norm. Such tools are capable of producing robust, industry compliant code with very little roll out time. This project documents the process of extending SIMULINK's automatic code generation tool for the AMP variant of µC/OS-II on Freescale's MPC5675K, dual-core Microcontroller Unit. This includes code generation from task based models and multi-rate models. Apart from this, it also de-scribes the development of additional software tools to allow semantically consistent communication between task on the same kernel and those across the kernels. / Dissertation/Thesis / Masters Thesis Computer Science 2014
463

Real-time Mesh Destruction System for a Video Game

Grönberg, Anton January 2017 (has links)
Destructive environments in video games are a feature that can give a gamemore depth and realism by being able to change the landscape or raze a building.This report talks about the research and implementation of a dynamicdestruction system for the video game Scrap Mechanic. The end results are asystem that could split convex 3D meshes to smaller pieces in almost real-time.It was a somewhat stable implementation that needs some future work beforeit can be used in the game. Therefore, in this report, things that could beimproved with the current implementation and how to use it are discussed.
464

Smooth silhouette rendering of low polygon models for computer games

Lindström, Kristian January 2006 (has links)
This dissertation presents a method capable of smoothing the silhouette of a 3D model using interpolation to find smooth edges. The method has as goal to be used with normal mapping to improve the performance and give a better result with a low polygonal count. To do this the lines located on the silhouette of a model is interpolated to find a curve that is used as clipping frame in the stencil buffer. This method is able to modify the silhouette for the better. The amount of interpolation is rather limited.
465

Replacing OSE with Real Time capable Linux

Boman, Simon, Rutgersson, Olof January 2009 (has links)
For many years OSE has been a common used operating system, with real time extensions enhancements, in embed-ded systems. But in the last decades, Linux has grown and became a competitor to common operating systems and, in recent years, even as an operating system with real time extensions. With this in mind, ÅF was interested in replacing the quite expensive OSE with some distribution of the open source based Linux on a PowerPC MPC8360. Therefore, our purpose with thesis is to implement Linux on the named platform and make some tests to see if it is possible to replace OSE with Linux. Using Linux has several advantages, for example it is free of charge to use and over the years the popularity of Linux within the developer community has resulted in numerous tools and utilities available for free. As a result, this study shows that Linux with real time extensions on the MPC8360 PowerPC platform is a viable alternative to OSE regarding cost efficiency, flexibility, adaptability and competence available on the market. Further studies can be done towards benchmarking for I/O systems and implementing support for more hardware on the MPC8360 AF platform.
466

Política de escalonamento de tempo real baseada em exigência para provisão de QoS absoluto em serviços Web / Exigency-based real-time scheduling policy to provide absolute QoS for web services

Lucas dos Santos Casagrande 14 June 2007 (has links)
Este trabalho apresenta um estudo, implementação e validação em ambiente simulado de uma política de escalonamento de tempo real para provisão de QoS absoluto em serviço Web. Sintetizando características de escalonamento de tempo real, com baixa latência e de modelo re-alimentado, a política proposta permite um ajuste ponderado pela quantificação da exigência à qual o sistema está submetido por meio de suas classes. A meta é oferecer ações imediatas às requisições mais urgentes, sem, entretanto, degradar a qualidade do sistema como um todo. Verificou-se que a estratégia de escalonamento baseada em exigência (EBS - Exigency-Based Scheduling) é benéfica para o controle da qualidade de serviço oferecida. Escalonar de forma a evitar demasiado peso imposto ao sistema permite que o servidor tenha mais condições de cumprir os requisitos contratuais. Também foi alvo do estudo a criação de uma métrica de avaliação da satisfação de atendimento por parte dos usuários dos serviços. Os resultados alcançados com o emprego da política EBS sinalizam uma melhoria em termos de qualidade de serviço e melhor satisfação dos clientes de forma balanceada / The present work presents a study, implementation and validation in a simulated environment of a real time scheduling policy to provide absolute QoS for web services. Synthesizing characteristic from real time scheduling, low latency and feedback scheduling, the proposed policy allows an adjustment weighed by the quantification of the exigency which the system is exposed through its classes. The goal is to offer immediate actions to most urgent requests, without decreasing the system quality as a whole. It was verified that the scheduling strategy based on exigency (EBS - Exigency-Based Scheduling) helps to control the quality of service offered. Scheduling in order to avoid imposing a heavy load to the system gives more condition to the server to fulfill the requirements agreed. Another goal of this work is the creation of a metrics to evaluate the client satisfaction. The results achieved with the EBS policy indicate a higher quality of service and better client satisfaction
467

Avaliação de desempenho da política EBS em uma arquitetura de escalonamento realimentada / Performance evaluation of EBS policy on a fedback scheduling architecture

Alessandro Nakamuta 27 April 2012 (has links)
Este trabalho apresenta uma avaliação do algoritmo EBS, uma política de escalonamento proposta para sistemas de tempo real flexíveis com qualidade de serviço baseado em limites superiores para tempos médios de resposta. Experimentos têm demonstrado propriedades vantajosas da política EBS em servidores Web com diferenciação de serviço. O objetivo do presente estudo é compreender o comportamento da EBS em relação à diferentes parâmetros que descrevem a carga de trabalho. Esse conhecimento é útil para obtenção de um melhor aproveitamento computacional. São apresentados experimentos e resultados que analisam a influência de cada um dos fatores considerados na qualidade do serviço oferecido. A partir desses resultados são tecidas conclusões acerca de abordagens para o dimensionamento de carga e de capacidade do servidor / This Master degree project has presented an evaluation of the EBS algorithm, a scheduling policy proposed for soft real-time systems with quality of service based on upper limits for average response times. Experiments have shown advantageous properties of the EBS policy on Web servers with service differentiation. The aim of this study is to understand the behavior of the EBS in relation to different parameters that describe the workload. This knowledge is useful for obtaining a better use of computing. Experiments and results are presented analyzing the influence of each factor considering the quality of service offered. From these results, conclusions are woven about approaches to the design load and server capacity
468

Desenvolvimento de um mestre PROFIBUS com a finalidade de análise de desempenho / Development of a PROFIBUS master for performance analyzing purpose

Valéria Paula Venturini 19 June 2007 (has links)
Quando se dispõe de um sistema de controle distribuído em tempo real, o atendimento aos requisitos temporais constitui-se num fator crucial para a aplicação. Assim, para garantir que tais requisitos sejam atendidos, é fundamental que o tráfego de mensagens no barramento seja gerenciado e controlado apropriadamente, evitando-se atrasos na comunicação para não prejudicar a performance do sistema e do produto final. Este trabalho apresenta um mestre PROFIBUS desenvolvido em PC, cujas finalidades foram analisar por meio de dados experimentais, a influência do parâmetro TTR no tempo de atualização das variáveis de processo no sistema e o tempo de reintegração da estação-mestre no anel lógico após perda de mensagem de token. / Using a real-time distributed control system, it is crucial to fullfill the time requirements for an application. Therefore, to guarantee that these requirements are fulfilled, it is essential to manage and control the message traffic in the bus properly, avoiding delays in the communication that could compromise the final product and the system performance. This study presents a PROFIBUS master based on PC. The main purpose of the PROFIBUS master is to analyze, using empirical data, the influence of the TTR parameter in the updating time of the process variables and the time interval to reintegrate a master device to the logical ring after a token message is lost.
469

Desenvolvimento e aplicação de RT-PCR em tempo real para Vesiculovirus brasileiros / Development and application of a real-time RT-PCR for brazilian Vesiculovirus

Aline Lavado Tolardo 06 February 2015 (has links)
Os Vesiculovirus são um gênero de vírus de RNA da família Rhabdoviridae que inclui os sorotipos Carajás, Cocal, Marabá, Piry, Alagoas e Indiana. Estes são causadores de estomatite vesicular em ruminantes e doença febril humana no Brasil. As vesiculoviroses e suas epidemiologias são pouco conhecidas em seres humanos. Ainda, os Vesiculovirus (VSV) são pouco diagnosticados no homem e em animais pela escassez de métodos laboratoriais diagnósticos. Por isso, objetivamos neste trabalho desenvolver e testar uma RT-PCR em tempo real, pelo método SYBR Green, visando à detecção de VSV brasileiros. Primers que amplificam parte do gene da proteína G dos VSV foram utilizados no teste o qual mostrou-se capaz de detectar genomas dos VSV Piry, Indiana, Alagoas e Carajás. O método foi usado para testar amostras séricas de pacientes com doença febril aguda, de bovinos, de equinos e de macerados de artrópodos. A RT-PCR em tempo real mostrou-se 100 vezes mais sensível que a RT-PCR convencional para Vesiculovirus e também, permitiu detectar até 10 cópias de RNA do vírus Piry. Ainda, a RT-PCR em tempo real para Vesiculovirus mostrou-se capaz de diagnosticar e quantificar o VSV Alagoas nas amostras séricas de bovinos e de equinos. Portanto, a RT-PCR em tempo real desenvolvida neste trabalho, provavelmente, será muito útil no diagnóstico e também, em futuras pesquisas, que permitirão ampliar o conhecimento epidemiológico, ainda pouco conhecido, sobre os Vesiculovirus. / The Vesiculovirus is a Rhabdoviridae family genre of RNA virus that includes serotypes Carajás, Cocal, Maraba, Piry, Alagoas and Indiana. These are causes of vesicular stomatitis in ruminants and human febrile illness in Brazil. The vesiculoviroses and its epidemiology are little known in humans. Still, Vesiculovirus (VSV) are poorly diagnosed in humans and laboratory animals by the lack of diagnostic methods. Therefore, we proposed in this work to develop and test a real-time RT-PCR by SYBR Green method, focusing on the detection of Brazilian VSV. Primers that amplify part of the VSV G protein gene were used in the test which proved capable of detecting genomes of VSV Piry, Indiana, Alagoas and Carajás. The method was used to test serum samples from patients with acute febrile disease, cattle, horses and macerated arthropods. Real time RT-PCR showed to be 100 times more sensitive than conventional RT-PCR for Vesiculovirus and also was possible to detect up to 10 RNA copies of the Piry virus. Also, the real-time RT-PCR for Vesiculovirus proved able to diagnose and quantify Alagoas VSV in serum samples from cattle and horses. Therefore, the real-time RT-PCR developed in this work will probably be very useful in the diagnosis and in future research, which will increase the epidemiological knowledge, as it is still little known about the Vesiculovirus.
470

Tecnologias system on chip e CAN em sistemas de controle distribuído / System on chip and CAN technologies into distributed control systems

Jean Mimar Santa Cruz Yabarrena 23 May 2006 (has links)
Sistemas de controle precisam trabalhar com restrições temporais rigorosas para garantir seu correto funcionamento, sendo por isso considerados sistemas de tempo-real. Quando tais sistemas são distribuídos, as redes de sensores, atuadores e controladores estão interligados em geral, por redes de campo. Nesse contexto, as redes de campo desempenham um papel extremamente importante no comportamento global do sistema. O presente trabalho de pesquisa apresenta a descrição do processo de desenvolvimento de um system on-chip (SoC) para um sistema de controle. Diferentemente das abordagens clássicas, o trabalho está focado em implementar o sistema baseado em um paradigma diferenciado, baseado em lógica reprogramável. Apresenta-se o projeto e construção dos IP cores necessários para controlar um motor DC, utilizando o barramento control area network (CAN) para obter uma plataforma distribuída. A arquitetura on chip utilizada está baseada na especificação CoreConnect da IBM. São expostos, ainda, trabalhos de simulação tanto dos componentes isolados, como do sistema integrado, de forma a realizar uma comparação qualitativa do processo de desenvolvimento / Control systems require strict time constraints to work properly, being therefore considered real-time systems. When such systems are distributed, controllers, sensors, and actuators are generally interconnected by fieldbuses. In this context the fieldbuses play an important role in the system global behavior. This research presents the description of the development process of a system-on-chip SoC. Differentiated from the classical approaches, this work focus the implementation of a reprogrammable logic based system. This work explain the necessary IP cores implementation, allowing a DC motor control, using a control area network (CAN) bus to reach a distributed platform. The on-chip architecture used is based on the IBM CoreConnect specification. Moreover it shows isolated components and integral system simulations, in such a way to obtain a qualitative comparison of development processes

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