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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.
141

Radar Emitter Emulation For Research And Experimental Purposes

Celebi, M.bahadir 01 August 2009 (has links) (PDF)
The scope of this thesis is to implement radar emitter emulator in a low cost, portablehardware for operational and educational purposes. The model enables pulse train generation in real environment belonging to radar emitters for military exercises. The motivation comes from another research area which is to design effective algorithms for deinterleaving mixed pulse sequences in a suitable hardware and this thesis, covers the work done for implementing a hardware that generates mixed pulse sequences. First of all, a basic radar emitter model is built up using laboratory instruments by considering basic radar emitter models. Technical specs of these instruments have to be known well to find out how many emitters can be emulated simultaneously and what the limits of these emulations are. After giving emulation results, trigging signal generator externally to obtain complex mixed pulse sequences is mentioned. In the following section related schematics are given about implementing radar emitters. Cost efficient way of emitter emulation is mentioned by using wideband RF synthesizer/VCO with integrated RF mixers and some microwave components in the following section. A board is designed including all required components to implement radar emitter emulation. Tests are implemented in laboratory environment. Finally test results and technical specifications of the design are given. Also cost calculations of the implemented designs are done in the final section and some examples related to the use of emulators in environmental scenarios are given. Future work is also explained again in this final section.
142

Attitude Control Hardware and Software for Nanosatellites

Lukaszynski, Pawel 05 December 2013 (has links)
The analysis, verification and emulation of attitude control hardware for nanosatellite spacecraft is described. The overall focus is on hardware that pertains to a multitude of missions currently under development at the University of Toronto Institute for Aerospace Studies - Space Flight Laboratory. The requirements for these missions push the boundaries of what is currently the accepted performance level of attitude control hardware. These new performance envelopes demand new acceptance test methods which must verify the performance of the attitude control hardware. In particular, reaction wheel and hysteresis rod actuators are the focus. Results of acceptance testing are further employed in post spacecraft integration for hardware emulation. This provides for a reduced mission cost as a function of reduced spare hardware. The overall approach provides a method of acceptance testing to new performance envelopes with the benefit of cost reduction with hardware emulation for simulations during post integration.
143

Attitude Control Hardware and Software for Nanosatellites

Lukaszynski, Pawel 05 December 2013 (has links)
The analysis, verification and emulation of attitude control hardware for nanosatellite spacecraft is described. The overall focus is on hardware that pertains to a multitude of missions currently under development at the University of Toronto Institute for Aerospace Studies - Space Flight Laboratory. The requirements for these missions push the boundaries of what is currently the accepted performance level of attitude control hardware. These new performance envelopes demand new acceptance test methods which must verify the performance of the attitude control hardware. In particular, reaction wheel and hysteresis rod actuators are the focus. Results of acceptance testing are further employed in post spacecraft integration for hardware emulation. This provides for a reduced mission cost as a function of reduced spare hardware. The overall approach provides a method of acceptance testing to new performance envelopes with the benefit of cost reduction with hardware emulation for simulations during post integration.
144

Virtual time-aware virtual machine systems

Yoginath, Srikanth B. 27 August 2014 (has links)
Discrete dynamic system models that track, maintain, utilize, and evolve virtual time are referred to as virtual time systems (VTS). The realization of VTS using virtual machine (VM) technology offers several benefits including fidelity, scalability, interoperability, fault tolerance and load balancing. The usage of VTS with VMs appears in two ways: (a) VMs within VTS, and (b) VTS over VMs. The former is prevalent in high-fidelity cyber infrastructure simulations and cyber-physical system simulations, wherein VMs form a crucial component of VTS. The latter appears in the popular Cloud computing services, where VMs are offered as computing commodities and the VTS utilizes VMs as parallel execution platforms. Prior to our work presented here, the simulation community using VM within VTS (specifically, cyber infrastructure simulations) had little awareness of the existence of a fundamental virtual time-ordering problem. The correctness problem was largely unnoticed and unaddressed because of the unrecognized effects of fair-share multiplexing of VMs to realize virtual time evolution of VMs within VTS. The dissertation research reported here demonstrated the latent incorrectness of existing methods, defined key correctness benchmarks, quantitatively measured the incorrectness, proposed and implemented novel algorithms to overcome incorrectness, and optimized the solutions to execute without a performance penalty. In fact our novel, correctness-enforcing design yields better runtime performance than the traditional (incorrect) methods. Similarly, the VTS execution over VM platforms such as Cloud computing services incurs large performance degradation, which was not known until our research uncovered the fundamental mismatch between the scheduling needs of VTS execution and those of traditional parallel workloads. Consequently, we designed a novel VTS-aware hypervisor scheduler and showed significant performance gains in VTS execution over VM platforms. Prior to our work, the performance concern of VTS over VM was largely unaddressed due to the absence of an understanding of execution policy mismatch between VMs and VTS applications. VTS follows virtual-time order execution whereas the conventional VM execution follows fair-share policy. Our research quantitatively uncovered the exact cause of poor performance of VTS in VM platforms. Moreover, we proposed and implemented a novel virtual time-aware execution methodology that relieves the degradation and provides over an order of magnitude faster execution than the traditional virtual time-unaware execution.
145

Rescuing the legacy project: a case study in digital preservation and technical obsolescence

Mickens, Leah M. 08 April 2009 (has links)
The ability to maintain continuous access to digital documents and artifacts is one of the most significant problems facing the archival, manuscript repository, and record management communities in the twenty-first century. This problem with access is particularly troublesome in the case of complex digital installments, which resist simple migration and emulation strategies. The Legacy Project, which was produced by the William Breman Jewish Heritage Museum in Atlanta, was created in the early 2000s as a means of telling the stories of Holocaust survivors who settled in metropolitan Atlanta. Legacy was an interactive multimedia kiosk that enabled museum visitors to read accounts, watch digital video, and examine photographs about these survivors. However, several years after Legacy was completed, it became inoperable, due to technological obsolescence. By using Legacy as a case study, I examine how institutions can preserve access to complex digital artifacts and how they can rescue digital information that is in danger of being lost.
146

Sob a superfície de imagens e discursos : como as pecuárias bovinas tornaram-se instituições no sul do Pará, Amazônia brasileira?

Claudino, Livio Sergio Dias January 2016 (has links)
Ce travail de thèse porte sur la manière dont les images et les discours produits sur l’Amazonie, ses populations et ses ressources, ont permis de faire du sud du Pará l'un des territoires d’expansion de l'élevage bovin les plus importants. Nous avons pour cela considéré l’élevage comme une institution, définie ici comme des foyers d’expérience en mouvement, posture à la base de la formulation de notre cadre théorique et méthodologique. Celui-ci nous a permis de nous écarter des variables explicatives conventionnelles et d’identifier plutôt les différents mécanismes et dispositifs qui ont rendu possible la justification et légitimité de cette activité dans une région où les forêts prédominent. Nous avons utilisé pour cela une approche multidisciplinaire alimentée principalement par Thorstein Veblen, Michel Foucault, Gilles Deleuze et Veena Das,. La polyphonie de cette tessiture théorique et méthodologique a favorisé la mise en place d'un regard distinct sur l'évolution de l'élevage bovin dans le biome de l'Amazonie. Nous avons utilisé l'analyse d'images, de discours et d'autres pratiques qui sont à la base de la formation et du fonctionnement de cette institution unique. L'accent est mis sur certains mécanismes qui en font partie : les déclarations de « peur de perdre » et « volonté de changer », ce que nous appelons ici « dispositif d'efficacité » et « émulation-force ». Ces mécanismes ont été mis en valeur par la relecture des écrits sur les élevages itinérants partant du Nord-Est du Brésil et arrivés dans le sud du Para, qui sont considérés ici sous le concept de « machine de guerre », aux côtés de la notion de «marges d'État ». / Essa tese analisa como as imagens e os discursos produzidos sobre a Amazônia, as populações e os recursos, desde uma perspectiva histórica, permitiram tornar o sul do Pará em um dos locais de maior expansão da criação de gado bovino. No primeiro momento, passamos a considerar a pecuária como uma instituição, definida aqui como focos de experiência em movimento, de modo a conduzir a formulação de um referencial teórico e metodológico que fugisse das variáveis explicativas convencionais, buscando, antes, os diversos mecanismos e dispositivos que possibilitaram a justificação/legitimidade da atividade em uma região onde predominavam florestas. Para esse percurso, valemo-nos de uma abordagem multidisciplinar fecundada principalmente por reflexões de autores como Thorstein Veblen, Michel Foucault, Gilles Deleuze, Veena Das, entre outros. A polifonia dessa tessitura teórica e metodológica aqui proposta favoreceu a constituição de um olhar distinto sobre a evolução da pecuária bovina no bioma amazônico, pensando-a como uma instituição, e trazendo para o escopo das análises as imagens, os discursos e outras práticas que permitiram a formação e funcionamento dessa instituição singular. Há uma ênfase para alguns mecanismos que fizeram parte dessa trama: os enunciados do “medo de perder” e da “vontade de transformar” e aquilo que aqui chamamos de “dispositivos de eficiência” e a “emulação-força”, que foram construídos na tese a partir da releitura dos escritos sobre a pecuária itinerante que saiu do Nordeste brasileiro e chegou ao sul do Pará, considerada aqui à luz do conceito de “máquina de guerra”, juntamente com a noção de “margens do estado”. / This thesis examines how the images and discourses produced on Amazon, populations and resources, from a historical perspective, allowed making the south of Para in one of the sites of greatest expansion of cattle breeding. At first we should consider livestock as an institution, defined here as moving experience outbreaks, so as to allow the formulation of a theoretical and methodological framework to flee the conventional explanatory variables, seeking rather to the various mechanisms and devices that allowed the justification / legitimacy of the activity in a region where forests predominated. For this route, we make use of a multidisciplinary approach enriched mainly by reflections of authors such as Thorstein Veblen, Michel Foucault, Gilles Deleuze, Veena Das, among others. This polyphony made possible by theoretical and methodological frameworks proposed here allowed the establishment of a different look at the evolution of cattle breedingin the Amazon biome, considering it as an institution, and bringing to the scope of the image analysis, speeches and other practices that allowed the formation and operation of this unique institution. There is an emphasis on some mechanisms that were part of this plot: the statements of the "fear of losing" and "wish of transforming" and what we here call "efficiency device" and "emulation-force", as well as a reinterpretation the writings on the itinerant cattle that came out from Northeast Brazil and reached the south of Pará, considered here in the light of the concept of a "war machine" with the notion of "state banks".
147

Design of Micro-Scale Energy Harvesting Systems for Low Power Applications Using Enhanced Power Management System

Ababneh, Majdi M 07 March 2018 (has links)
The great innovations of the last century have ushered continuous progress in many areas of technology, especially in the form of miniaturization of electronic circuits. This progress shows a trend towards consistent decreases in power requirements due to miniaturization. According to the ITRS and industry leaders, such as Intel, the challenge of managing and providing power efficiency still persist as scaling down of devices continues. A variety of power sources can be used in order to provide power to low power applications. Few of these sources have favorable characteristics and can be designed to deliver maximum power such as the novel mini notched turbine used as a source in this work. The MiNT is a novel device that can be used as a feasible energy source when integrated into a system and evaluated for power delivery as investigated in this work. As part of this system, a maximum power point tracking system provides an applicable solution for capturing enhanced power delivery for an energy harvesting system. However, power efficiency and physical size are adversely affected by the characteristics and environment of many energy harvesting systems and must also be addressed. To address these issues, an analysis of mini notched turbine, a RF rectenna, and an enhanced maximum power point tracking system is presented and verified using simulations and measurements. Furthermore, mini notched energy harvesting system, RF rectenna energy harvesting system, and enhanced maximum power point tracking system are developed and experimental data analyzed. The enhanced maximum power point tracking system uses a resistor emulation technique and particle swarm optimization (PSO) to improve the power efficiency and reduce the physical size. This new innovative design improves the efficiency of optimized power management circuitry up to 7% compared to conventional power management circuits over a wide range of input power and range of emulated resistances, allowing more power to be harvested from small energy harvesting sources and delivering it to the load such as smart sensors. In addition, this is the first IC design to be implemented and tested for the patented mini notched turbine (MiNT) energy harvesting device. Another advantage of the enhanced power management system designed in this work is that the proposed approach can be utilized for extremely small energy sources and because of that the proposed work is valid for low emulated resistances. and systems with low load resistance Overall, through the successful completion of this work, various energy harvesting systems can have the ability to provide enhanced power management as the IC industry continues to progress toward miniaturization of devices and systems.
148

Sob a superfície de imagens e discursos : como as pecuárias bovinas tornaram-se instituições no sul do Pará, Amazônia brasileira?

Claudino, Livio Sergio Dias January 2016 (has links)
Ce travail de thèse porte sur la manière dont les images et les discours produits sur l’Amazonie, ses populations et ses ressources, ont permis de faire du sud du Pará l'un des territoires d’expansion de l'élevage bovin les plus importants. Nous avons pour cela considéré l’élevage comme une institution, définie ici comme des foyers d’expérience en mouvement, posture à la base de la formulation de notre cadre théorique et méthodologique. Celui-ci nous a permis de nous écarter des variables explicatives conventionnelles et d’identifier plutôt les différents mécanismes et dispositifs qui ont rendu possible la justification et légitimité de cette activité dans une région où les forêts prédominent. Nous avons utilisé pour cela une approche multidisciplinaire alimentée principalement par Thorstein Veblen, Michel Foucault, Gilles Deleuze et Veena Das,. La polyphonie de cette tessiture théorique et méthodologique a favorisé la mise en place d'un regard distinct sur l'évolution de l'élevage bovin dans le biome de l'Amazonie. Nous avons utilisé l'analyse d'images, de discours et d'autres pratiques qui sont à la base de la formation et du fonctionnement de cette institution unique. L'accent est mis sur certains mécanismes qui en font partie : les déclarations de « peur de perdre » et « volonté de changer », ce que nous appelons ici « dispositif d'efficacité » et « émulation-force ». Ces mécanismes ont été mis en valeur par la relecture des écrits sur les élevages itinérants partant du Nord-Est du Brésil et arrivés dans le sud du Para, qui sont considérés ici sous le concept de « machine de guerre », aux côtés de la notion de «marges d'État ». / Essa tese analisa como as imagens e os discursos produzidos sobre a Amazônia, as populações e os recursos, desde uma perspectiva histórica, permitiram tornar o sul do Pará em um dos locais de maior expansão da criação de gado bovino. No primeiro momento, passamos a considerar a pecuária como uma instituição, definida aqui como focos de experiência em movimento, de modo a conduzir a formulação de um referencial teórico e metodológico que fugisse das variáveis explicativas convencionais, buscando, antes, os diversos mecanismos e dispositivos que possibilitaram a justificação/legitimidade da atividade em uma região onde predominavam florestas. Para esse percurso, valemo-nos de uma abordagem multidisciplinar fecundada principalmente por reflexões de autores como Thorstein Veblen, Michel Foucault, Gilles Deleuze, Veena Das, entre outros. A polifonia dessa tessitura teórica e metodológica aqui proposta favoreceu a constituição de um olhar distinto sobre a evolução da pecuária bovina no bioma amazônico, pensando-a como uma instituição, e trazendo para o escopo das análises as imagens, os discursos e outras práticas que permitiram a formação e funcionamento dessa instituição singular. Há uma ênfase para alguns mecanismos que fizeram parte dessa trama: os enunciados do “medo de perder” e da “vontade de transformar” e aquilo que aqui chamamos de “dispositivos de eficiência” e a “emulação-força”, que foram construídos na tese a partir da releitura dos escritos sobre a pecuária itinerante que saiu do Nordeste brasileiro e chegou ao sul do Pará, considerada aqui à luz do conceito de “máquina de guerra”, juntamente com a noção de “margens do estado”. / This thesis examines how the images and discourses produced on Amazon, populations and resources, from a historical perspective, allowed making the south of Para in one of the sites of greatest expansion of cattle breeding. At first we should consider livestock as an institution, defined here as moving experience outbreaks, so as to allow the formulation of a theoretical and methodological framework to flee the conventional explanatory variables, seeking rather to the various mechanisms and devices that allowed the justification / legitimacy of the activity in a region where forests predominated. For this route, we make use of a multidisciplinary approach enriched mainly by reflections of authors such as Thorstein Veblen, Michel Foucault, Gilles Deleuze, Veena Das, among others. This polyphony made possible by theoretical and methodological frameworks proposed here allowed the establishment of a different look at the evolution of cattle breedingin the Amazon biome, considering it as an institution, and bringing to the scope of the image analysis, speeches and other practices that allowed the formation and operation of this unique institution. There is an emphasis on some mechanisms that were part of this plot: the statements of the "fear of losing" and "wish of transforming" and what we here call "efficiency device" and "emulation-force", as well as a reinterpretation the writings on the itinerant cattle that came out from Northeast Brazil and reached the south of Pará, considered here in the light of the concept of a "war machine" with the notion of "state banks".
149

Metodologia de injeção de falhas baseada em emulação de processadores / Fault injection methodology based on processor emulation

Geissler, Filipe de Aguiar January 2014 (has links)
Esta dissertação tem por finalidade apresentar uma metodologia de injeção de falhas baseada em emulação de processadores. Os efeitos causados pela radiação em processadores, operando no espaço ou em altitudes elevadas, têm sido estudados na literatura para o desenvolvimento de mecanismos de tolerância a falhas. Com a crescente popularidade do uso de processadores comerciais, (COTS – do inglês, Commercial Off-The-Shelf), em aplicações críticas, uma série de preocupações tem surgido devido a falta de confiabilidade apresentada por estes sistemas. Sendo desprovidos de mecanismos de tolerância para melhor robustez em ambientes espaciais, estes dispositivos comerciais são mais suscetíveis aos efeitos da radiação. Neste contexto, técnicas de tolerância a falhas baseadas em software vêm sendo estudadas a fim de aumentar a confiabilidade desta abordagem. Para a devida validação de tais mecanismos de tolerância, o uso de técnicas de injeção de falhas é aplicável. Estas técnicas de injeção de falhas possuem uma série de limitações que podem inviabilizar a sua aplicabilidade, dependendo da abordagem utilizada. Fatores como custo, indisponibilidade da descrição de hardware – utilizada em técnicas de injeção de falhas por simulação ou emulação em FPGA (Field Programmable Gate Array), e o longo tempo necessário para execução dos experimentos, são alguns exemplos de limitações das técnicas disponíveis. Com base nisso, a metodologia de injeção de falhas alternativa apresentada neste trabalho, visa reduzir as limitações presentes nas mais diversas técnicas. Baseada na utilização de tradução dinâmica de instruções, para acelerar o processo de execução de aplicações em emuladores, a metodologia apresenta um modelo de falhas para efeitos transientes e permanentes, aplicáveis neste cenário. Como método de classificação dos efeitos observados neste processo, um modelo presente na literatura foi utilizado. Para validação desta metodologia, um injetor de falhas baseado no emulador QEMU foi desenvolvido. Posteriormente, um estudo de caso com o injetor de falhas foi realizado para três estruturas de software distintas executando individualmente no processador MIPS 24kc, representando três níveis de complexidade distintos: sistema operacional Linux, sistema de tempo real, (RTEMS – do inglês, Real-Time Operating System), e uma aplicação dedicada. Cada sistema foi submetido a uma campanha de injeção de falhas transientes para emulação de efeitos singulares (SEU – do inglês, Single Event Upset). Como alvo de falhas, foram selecionados os registradores do processador e a memória de dados. Por fim, as análises obtidas através dos experimentos mostraram os diferentes efeitos observados para os três níveis de complexidade dos softwares executados. Além disso, se pôde avaliar o desempenho do injetor de falhas, disponibilizando ao final do trabalho uma ferramenta para o auxílio no desenvolvimento de técnicas de tolerância a falhas por software. / This dissertation aims to present a fault injection methodology based on microprocessor emulation. The effects caused by radiation in microprocessors, operating in space or at high altitudes, have been studied in the literature for the development of fault tolerance mechanisms. With the growing popularity of COTS (Commercial Off-The-Shelf) processors usage, in critical applications, a number of concerns have arisen due to the lack of reliability, presented in these systems. Due to the lack of fault tolerance mechanisms, these COTS devices are more susceptible to radiation effects. In this context, software-based fault tolerance techniques have been studied in the literature in order to increase the reliability of this approach. To validate such fault tolerance mechanisms, the use of fault injection techniques is applicable. These fault injection techniques have several limitations which can preclude their applicability, depending on of its design approach. Factor such as cost, unavailability of hardware description – used by fault injection techniques based on simulation or emulation with FPGA (Field Programmable Gate Array), and the long time demanded to execute experiments, are some examples of limitations in the available techniques. Based on this, the alternative fault injection methodology presented in this work aims to reduce these limitations. Based on the dynamic translation of instructions usage to accelerate the execution of application on emulators, the methodology presents a fault model for transient and permanent faults applicable in this scenario. As a classification method of the observed effects in this process, a model in the literature has been used. To validate this methodology, a fault injector based on the QEMU emulator was implemented. Later, a case study with the fault injector was performed for three software structures running at a time on a MIPS 24kc processor, representing three different levels of complexity: Linux operating system, RTEMS (Real-Time Operating System), and a dedicated application. Each system was submitted to a fault injection campaign emulating Single Event Upsets (SEUs). As fault targets it was selected the processor registers and the data memory. Finally, the analysis obtained with the experiments showed the different effects observed for the three levels of complexity. Besides that, the fault injector performance could be evaluated providing in the end a tool to help in the development of software-based fault injection techniques.
150

Metodologia de injeção de falhas baseada em emulação de processadores / Fault injection methodology based on processor emulation

Geissler, Filipe de Aguiar January 2014 (has links)
Esta dissertação tem por finalidade apresentar uma metodologia de injeção de falhas baseada em emulação de processadores. Os efeitos causados pela radiação em processadores, operando no espaço ou em altitudes elevadas, têm sido estudados na literatura para o desenvolvimento de mecanismos de tolerância a falhas. Com a crescente popularidade do uso de processadores comerciais, (COTS – do inglês, Commercial Off-The-Shelf), em aplicações críticas, uma série de preocupações tem surgido devido a falta de confiabilidade apresentada por estes sistemas. Sendo desprovidos de mecanismos de tolerância para melhor robustez em ambientes espaciais, estes dispositivos comerciais são mais suscetíveis aos efeitos da radiação. Neste contexto, técnicas de tolerância a falhas baseadas em software vêm sendo estudadas a fim de aumentar a confiabilidade desta abordagem. Para a devida validação de tais mecanismos de tolerância, o uso de técnicas de injeção de falhas é aplicável. Estas técnicas de injeção de falhas possuem uma série de limitações que podem inviabilizar a sua aplicabilidade, dependendo da abordagem utilizada. Fatores como custo, indisponibilidade da descrição de hardware – utilizada em técnicas de injeção de falhas por simulação ou emulação em FPGA (Field Programmable Gate Array), e o longo tempo necessário para execução dos experimentos, são alguns exemplos de limitações das técnicas disponíveis. Com base nisso, a metodologia de injeção de falhas alternativa apresentada neste trabalho, visa reduzir as limitações presentes nas mais diversas técnicas. Baseada na utilização de tradução dinâmica de instruções, para acelerar o processo de execução de aplicações em emuladores, a metodologia apresenta um modelo de falhas para efeitos transientes e permanentes, aplicáveis neste cenário. Como método de classificação dos efeitos observados neste processo, um modelo presente na literatura foi utilizado. Para validação desta metodologia, um injetor de falhas baseado no emulador QEMU foi desenvolvido. Posteriormente, um estudo de caso com o injetor de falhas foi realizado para três estruturas de software distintas executando individualmente no processador MIPS 24kc, representando três níveis de complexidade distintos: sistema operacional Linux, sistema de tempo real, (RTEMS – do inglês, Real-Time Operating System), e uma aplicação dedicada. Cada sistema foi submetido a uma campanha de injeção de falhas transientes para emulação de efeitos singulares (SEU – do inglês, Single Event Upset). Como alvo de falhas, foram selecionados os registradores do processador e a memória de dados. Por fim, as análises obtidas através dos experimentos mostraram os diferentes efeitos observados para os três níveis de complexidade dos softwares executados. Além disso, se pôde avaliar o desempenho do injetor de falhas, disponibilizando ao final do trabalho uma ferramenta para o auxílio no desenvolvimento de técnicas de tolerância a falhas por software. / This dissertation aims to present a fault injection methodology based on microprocessor emulation. The effects caused by radiation in microprocessors, operating in space or at high altitudes, have been studied in the literature for the development of fault tolerance mechanisms. With the growing popularity of COTS (Commercial Off-The-Shelf) processors usage, in critical applications, a number of concerns have arisen due to the lack of reliability, presented in these systems. Due to the lack of fault tolerance mechanisms, these COTS devices are more susceptible to radiation effects. In this context, software-based fault tolerance techniques have been studied in the literature in order to increase the reliability of this approach. To validate such fault tolerance mechanisms, the use of fault injection techniques is applicable. These fault injection techniques have several limitations which can preclude their applicability, depending on of its design approach. Factor such as cost, unavailability of hardware description – used by fault injection techniques based on simulation or emulation with FPGA (Field Programmable Gate Array), and the long time demanded to execute experiments, are some examples of limitations in the available techniques. Based on this, the alternative fault injection methodology presented in this work aims to reduce these limitations. Based on the dynamic translation of instructions usage to accelerate the execution of application on emulators, the methodology presents a fault model for transient and permanent faults applicable in this scenario. As a classification method of the observed effects in this process, a model in the literature has been used. To validate this methodology, a fault injector based on the QEMU emulator was implemented. Later, a case study with the fault injector was performed for three software structures running at a time on a MIPS 24kc processor, representing three different levels of complexity: Linux operating system, RTEMS (Real-Time Operating System), and a dedicated application. Each system was submitted to a fault injection campaign emulating Single Event Upsets (SEUs). As fault targets it was selected the processor registers and the data memory. Finally, the analysis obtained with the experiments showed the different effects observed for the three levels of complexity. Besides that, the fault injector performance could be evaluated providing in the end a tool to help in the development of software-based fault injection techniques.

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