abstract: The efficiency of spacecraft’s solar cells reduces over the course of their operation. Traditionally, they are configured to extract maximum power at the end of their life and not have a system which dynamically extracts the maximum power over their entire life. This work demonstrates the benefit of dynamic re-configuration of spacecraft’s solar arrays to access the full power available from the solar panels throughout their lifetime. This dynamic re-configuration is achieved using enhancement mode GaN devices as the switches due to their low Ron and small footprint. This work discusses hardware Implementation challenges and a prototype board is designed using components-off-the-shelf (COTS) to study the behavior of photovoltaic (PV) panels with different configurations of switches between 5 PV cells. The measurement results from the board proves the feasibility of the idea, showing the power improvements of having the switch structure. The measurement results are used to simulate a 1kW satellite system and understand practical trade-offs of this idea in actual satellite power systems. Additionally, this work also presents the implementation of CMOS controller integrated circuit (IC) in 0.18um technology. The CMOS controller IC includes switched-capacitor converters in open loop to provide the floating voltages required to drive the GaN switches. Each CMOS controller IC can drive 10 switches in series and parallel combination. Furthermore, the designed controller IC is expected to operate under 300MRad of total dose radiation, thus enabling the controller modules to be placed on the solar cell wings of the satellites. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2019

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Yes / This paper examines the relationship between open innovation (OI) practices (inbound and coupled) and innovation performance in service firms. Specifically, it invokes a dynamic capabilities perspective to propose the differential moderating effects of two forms of reconfiguration capabilities, strategic reconfiguration capability (SRC) and operational reconfiguration capability (ORC), on the focal relationship. Based on a sample of service sector firms drawn from the UK Community Innovation Survey, our analysis shows the positive combinative effects of SRC and coupled OI on radical innovation outcomes and those of ORC and coupled OI on incremental innovation outcomes. The findings of differential moderating effects underscore the need to assess the boundary conditions within which OI positively impacts on innovation outcomes and offer insights to managers on the importance of strategic and operational reconfiguration capabilities for achieving better innovation outcomes from OI practices.

Modern Field-Programmable Gate Arrays (FPGAs) are no longer used to implement small “glue logic” circuitries. The high-density of reconfigurable logic resources in today’s FPGAs enable the implementation of large systems in a single chip. FPGAs are highly flexible devices; their functionality can be altered by simply loading a new binary file in their configuration memory. While the flexibility of FPGAs is comparable to General-Purpose Processors (GPPs), in the sense that different functions can be performed using the same hardware, the performance gain that can be achieved using FPGAs can be orders of magnitudes higher as FPGAs offer the ability for customisation of parallel computational architectures. Dynamic Partial Reconfiguration (DPR) allows for changing the functionality of certain blocks on the chip while the rest of the FPGA is operational. DPR has sparked the interest of researchers to explore new computational platforms where computational tasks are off-loaded from a main CPU to be executed using dedicated reconfigurable hardware accelerators configured on demand at run-time. By having a battery of custom accelerators which can be swapped in and out of the FPGA at runtime, a higher computational density can be achieved compared to static systems where the accelerators are bound to fixed locations within the chip. Furthermore, the ability of relocating these accelerators across several locations on the chip allows for the implementation of adaptive systems which can mitigate emerging faults in the FPGA chip when operating in harsh environments. By porting the appropriate fault mitigation techniques in such computational platforms, the advantages of FPGAs can be harnessed in different applications in space and military electronics where FPGAs are usually seen as unreliable devices due to their sensitivity to radiation and extreme environmental conditions. In light of the above, this thesis investigates the deployment of DPR as: 1) a method for enhancing performance by efficient exploitation of the FPGA resources, and 2) a method for enhancing the reliability of systems intended to operate in harsh environments. Achieving optimal performance in such systems requires an efficient internal configuration management system to manage the reconfiguration and execution of the reconfigurable modules in the FPGA. In addition, the system needs to support “fault-resilience” features by integrating parameterisable fault detection and recovery capabilities to meet the reliability standard of fault-tolerant applications. This thesis addresses all the design and implementation aspects of an Internal Configuration Manger (ICM) which supports a novel bitstream relocation model to enable the placement of relocatable accelerators across several locations on the FPGA chip. In addition to supporting all the configuration capabilities required to implement a Reconfigurable Operating System (ROS), the proposed ICM also supports the novel multiple-clone configuration technique which allows for cloning several instances of the same hardware accelerator at the same time resulting in much shorter configuration time compared to traditional configuration techniques. A faulttolerant (FT) version of the proposed ICM which supports a comprehensive faultrecovery scheme is also introduced in this thesis. The proposed FT-ICM is designed with a much smaller area footprint compared to Triple Modular Redundancy (TMR) hardening techniques while keeping a comparable level of fault-resilience. The capabilities of the proposed ICM system are demonstrated with two novel applications. The first application demonstrates a proof-of-concept reliable FPGA server solution used for executing encryption/decryption queries. The proposed server deploys bitstream relocation and modular redundancy to mitigate both permanent and transient faults in the device. It also deploys a novel Built-In Self- Test (BIST) diagnosis scheme, specifically designed to detect emerging permanent faults in the system at run-time. The second application is a data mining application where DPR is used to increase the computational density of a system used to implement the Frequent Itemset Mining (FIM) problem.

Reproduction de : Thèse de doctorat : Génie électrique : Toulouse, INPT : 2006. Reproduction de : Thèse de doctorat : Génie électrique : Tunis, ENIT : 2006. / Thèse soutenue en co-tutelle. Titre provenant de l'écran-titre. Bibliogr. 54 réf.

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FPGA design implementation and debug tools have not kept pace with the advances in FPGA device density. The emphasis on area optimization and circuit speed has resulted in longer runtimes of the implementation tools. We address the implementation problem using a divide-and-conquer approach in which some device area and circuit speed is sacrificed for improved implementation turnaround time. The PATIS floorplanner enables dynamic modular design that accelerates implementation for incremental changes to a design. While the existing implementation flows facilitate timing closure late in the design cycle by reusing the layout of unmodified blocks, dynamic modular design accelerates implementation by achieving timing closure for each block independently. A complete re-implementation is still rapid as the design blocks can be processed by independent and concurrent invocations of the standard tools. PATIS creates the floorplan for implementing modules in the design. Bus macros serve as module interfaces and enable independent implementation of the modules. The dynamic modular design flow achieves around 10x speedup over the standard design flow for our benchmark designs. / Master of Science

La complexité croissante de notre environnement socio-économique se traduit en génie logiciel par une augmentation de la taille des systèmes et par conséquent de leur complexité. Les systèmes actuels sont le plus souvent concurrents, distribués à grande échelle et composés d’autre systèmes. Ils sont alors appelés Systèmes de Systèmes (SdS). La complexité des systèmes de systèmes réside dans leurs cinq caractéristiques intrinsèques qui sont : l’indépendance opérationnelle des systèmes constituants, leur indépendance managériale, la distribution géographique, l’existence de comportements émergents, et enfin un processus de développement évolutionnaire. Les SdS évoluent dans des environnements non prévisibles et intègrent constamment de nouveaux systèmes. Nous avons traité la problématique du développement évolutionnaire d’un SdS en utilisant la reconfiguration dynamique. Nous avons défini un processus pour élaborer des modèles de configurations et un processus de conception de la reconfiguration intégrant le concept de patron de reconfiguration. Pour la validité et la faisabilité de notre approche, nous avons développé un framework d’expérimentation basé sur notre cas d’étude réel d’organisation des systèmes de secours français. / The growing complexity of our socio-economic environment is reflected in software engineering by an increase of the size of systems and therefore their complexity. Current systems are mostly concurrent, widely distributed and composed of other systems. They are then called Systems of Systems (SoS). The complexity of systems of systems lies in five intrinsic characteristics: the operational independence of the constituent systems, their managerial independence, the geographical distribution, the existence of emerging behaviours, and finally an evolutionary development process.SoS evolve in unpredictable environment and are constantly integrating new systems. We deal with the problem of the evolutionary development of a SoS by using dynamic reconfiguration. We have defined a process for developing configuration models and a reconfiguration design process incorporating the concept of reconfiguration pattern. For the validity and feasibility of our approach, we have developed an experimental framework based on our real case study of organization of the French emergency service.

Notre objectif principal est de permettre l’utilisation de propriétés temporelles dans une politique d’adaptation en tenant compte des spécificités de la vérification à l’exécution.Pour y répondre, nous définissons un modèle de système à composants supportant les reconfigurations dynamiques. Nous introduisons les reconfigurations gardées qui nous permettent d’utiliser des opérations primitives en tant que “briques” pour construire des reconfigurations plus élaborées impliquant des constructions, non seulement, séquentielles, mais aussi alternatives ou répétitives, tout en garantissant la consistance des configurations du système.En outre, nous étendons (aux événements externes) la logique temporelle utilisée précédemment pour exprimer des contraintes architecturales sur des configurations. Avec une sémantique, dite progressive, nous pouvons, dans la plupart des cas, évaluer (de fac¸on centralisée ou décentralisée)une expression temporelle pour une configuration donnée `a partir d’ évaluations déjà réalisées à la seule configuration précédente. Nous utilisons cette logique dans des politiques d’adaptation permettant de guider et contrôler les reconfigurations de systèmes à composants à l’exécution.Enfin, l’implémentation de politiques d’adaptation a été expérimentée dans divers cas d’ études sur les plateformes Fractal et FraSCAti. Nous utilisons notamment le fuzzing comportemental afin de pouvoir tester des aspects spécifiques d’une politique d’adaptation. / Our main goal is to allow the usage of temporal properties within an adaptation policy while takinginto account runtime verification specificities.In order to reach it, we define a component-based system model that supports dynamicreconfigurations. We introduce guarded reconfigurations in order to use primitive operations as“building blocks” to craft more elaborated reconfigurations involving, not only sequential, but also,alternate and repetitive constructs while ensuring the system’s configurations consistency.Furthermore, we extend (to external events) the temporal logic previously used to expressarchitectural constraints on configurations. Using, so called, progressive semantics, we can, in mostof the cases, evaluate (in a centralised or decentralised fashion) a temporal expression for a givenconfiguration using evaluations performed only at the previous configuration. We use this logic withinadaptation policies enabling the steering and control of dynamic reconfigurations at runtime.Finally, we implemented such adaptation policies in various case studies using frameworks such asFractal and FraSCAti. We also use behavioural fuzzing to test various specific aspects of a givenadaptation policy.

L’interaction entre ceux qui se définissent comme autochtones et les allochtones s’illustre de façon manifeste dans la commune rurale de Sanso en raison de la découverte et de l’exploitation d’une mine d’or à partir de l’année 2000. Nous avons choisi ce site car il est considéré comme exemplaire tant par sa forte production aurifère (avec plus 20 millions de minerais en 2012, depuis sa mise en service elle a injecté 400 milliards Franc CFA dans l’économie nationale) que pour les projets de développement mis en place par la société minière. Nous avons analysé les changements sociaux au delà des discours politiques, juridiques et économiques sur l’or tout se référant sur l’environnement social et les changements qui le caractérisent, L’implantation des allochtones a provoqué de nombreuses modifications qui affectent les relations sociales telles que tes systèmes de parenté, les stratégies d’alliance ou encore les règles de pouvoir. Notre recherche s’est focalisée sur les interactions entre les autochtones et les allochtones. Les comportements traditionnels sociaux, politiques ou quotidiens ont connu des mouvements au profit de la généralisation d’un mode de vie unique inspiré par la ville. Notre problématique se résume donc à la question suivante : quels sont les changements provoqués par le déséquilibre démographique entre les habitants originaires de la commune et ceux qui sont venus s’y installer depuis l’exploitation de la mine et les incidences sur les conditions socio-économiques de la commune rurale de Sanso ? De manière plus spécifique, cette recherche analyse les interactions entre les autochtones et les allochtones dans la sphère de la modernité. Afin de rendre compte le plus finement possible des changements intervenus, l’analyse documentaire. l’observation in situ et les entretiens constituent les trois piliers de notre méthodologie / The interaction between those who define themselves as indigenous and non·indigenous stands out overtly in rural Sanso commune due to the discover and exploitation of a gold mine from 2000. We chose this site because it is considered exemplary both for its high gold production and for its development projects implemented by the mining company. Since its commissioning, Morila gold mine has extracted more than 200 tons of gold and contributed up lo 1,000 billion CFA francs in the national economy (customs duty. dividend taxes,). But if you exceed the posted showcase figures, social complexity, frustrations and daily questioning of the inhabitants of Sanso more than one third of the local population complain about the high cost of life, access to health care problems, drinking water. overstaffing in school classes, upheavals, environmental changes. Installation of non-native (regional, national and international) made numerous changes that affect social relationships such as kinship systems, alliance strategies and the rules of power. Our research has focused on interactions between natives and non-natives. Traditional social attitudes. political or experienced daily movements in favor of the generalization of a unique way of life inspired by other referential. It would. however. be wrong to think that people in the rural community of Sanso passively undergo transformations imported from outside. They involved in changes that affect the area. According to their practices and representations, they orient indeed local transformations, in a way not always expected by the Stale or mining jurisdictions such as deforestation resulting in the: destruction of wildlife habitats and the transformation of the traditional hunting for lucrative purposes. Based on the three priority areas identified by the Malian government and the direction of Morila SA, our analysis thus includes changes to both desired and undesired. which took shape al the option of development of Morita SA mine in the rural town of Sanso. Our problem is summarized in the following question: What are the changes caused by the demographic imbalance between the inhabitants from the commune and those who came to settle there since the operation of the mine? What were the implications of these changes on the socio-economic conditions of the rural commune of Sanso? More specifically, this research analyzes the interactions between indigenous and non· indigenous in a context of modernity. So as to relate as more specifically as possible the changes, document analysis, in-situ observation and interviews arc the three pillars of our methodology