Tesis sobre el tema "Systèmes à composants multiples"
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Vu, Hai Canh. "Stratégies de regroupement pour la maintenance des systèmes à composants multiples avec structure complexe". Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0008/document.
Texto completoIn the recent decades, with a strong development of the global economy and new technologies, the structure of industrial systems is more and more complex. It can be a combination of elementary structures such as series structures, parallel structures, series-parallel structures, etc. In the literature, the most work focused on developing grouping strategies by considering series structures. This assumption is sometimes much penalized and limited the application of these strategies in reality. Therefore, the main objective of this thesis is to develop dynamic and stationary grouping strategies for the maintenance of multi-component systems with complex structure. These strategies have been developed for age-based models with non-negligible maintenance durations. In addition, dynamic conditions (dynamic context) such as maintenance opportunities, changes of the structure, etc., are considered and integrated into the maintenance scheduling.Our studies show the necessity and the difficulties of taking into account of the complex structure in the maintenance decisions. Numerical examples confirm the advantages of our maintenance strategies by comparing with other existing strategies in the literature
Chefrour, Djalel. "Plate-forme de composants logiciels pour la coordination des adaptations multiples en environnement dynamique". Phd thesis, Université Rennes 1, 2005. http://tel.archives-ouvertes.fr/tel-00011148.
Texto completopour l'adaptation de composants logiciels et pour leur coordination en environnement
dynamique.
Nous proposons une capture des mécanismes de l'adaptabilité dans un modèle de
composants générique basé sur la réflexivité et les techniques objet. Ces composants
reposent sur un service de surveillance de l'environnement et sur un intergiciel de coordination
des adaptations. La coordination inclut la gestion des dépendances entre les
composants interagissants et/ou concurrents.
En instaurant la séparation des préoccupations, notre approche facilite la tâche du
développeur à qui nous offrons des langages déclaratifs pour spécifier les politiques qui
contrôlent les adaptations des composants et leur coordination dans des scripts séparés.
Nous avons montré l'utilité de notre modèle, appelé Aceel, en l'utilisant pour développer
une application vidéo et un navigateurWeb adaptables en environnement mobile.
Li, Zhi. "Commande optimale (en Production et Stock) de Systèmes Assemble-To-Order (ATO) avec prise en compte de demandes en composants individuels". Phd thesis, Ecole Centrale de Lille, 2013. http://tel.archives-ouvertes.fr/tel-00866378.
Texto completoLapertot, Arnaud. "Méthodologie d'optimisation de composants et de systèmes énergétiques complexes : application au secteur résidentiel". Thesis, Aix-Marseille, 2021. http://www.theses.fr/2021AIXM0624.
Texto completoThis thesis is dedicated to the optimization of components and energy systems with an application in the residential sector. The methodology developed is composed of a sensitivity analysis, a multi-objective optimization and a multi-criteria decision-making aid to select the best compromise.First of all, an optimization of a domestic hot water production system is implemented numerically and is based on an experimental set-up in the IUSTI laboratory. The aim of this study is to optimize the performance of a heat pump-based system by improving its regulation according to different drawing profiles. Then, the procedure is applied to the parametric optimization of an earth-air heat exchanger (EAHE). The system uses geothermal resources to preheat or cool the air in a building by ventilation. The model of the earth-air heat exchanger has been experimentally validated with an existing geothermal platform at Strasbourg. A system that combines an EAHE, a double flow ventilation and a heat pump is also studied. Optimal sizing makes it possible to obtain a system that is profitable, autonomous and efficient for the different climates considered. Finally, the process is applied to the topological optimization of heat exchangers. The procedure identifies the set of topologies that has a good compromise between pressure drops and heat transfer. The decision aid methodology selects the final topology that allows to have an optimized distribution of solid elements in order to obtain the best compromise between these objectives
Dinh, Duc-Hanh. "Opportunistic Predictive Maintenance for Multi-Component Systems with Multiple Dependences". Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0171.
Texto completoRecently, maintenance modeling for multi-component systems with dependences (economic, stochastic, and/or structural dependences) has been extensively studied. However, most of the existing studies only consider one type of dependence since combining more than one makes the models too complicated to analyze and solve. However, in practice, several types of dependences, especially, the economic and structural dependences, may exist together in the system. To face this issue, the main objective of this thesis is to consider both economic and structural dependences in maintenance modeling and optimization for multi-component systems in framework of predictive maintenance. For this purpose, the impacts of economic and structural dependences on the maintenance cost, duration and the degradation process of the components are firstly investigated. Mathematical models for quantifying the impacts of the economic and structural dependences are then developed. Finally, a multi-level opportunistic maintenance policy is proposed to consider the impacts of these dependences between components.Due to the structural dependence between components, when a maintenance (preventive or corrective action) occurs, only few components need to be disassembled. The disassembled components are subjected to both economic and structural dependences while the non-disassembled components are subjected to only economic dependence. In that way, the proposed maintenance policy is characterized by one preventive threshold, that is used to select survival components for preventive maintenance, and two opportunistic maintenance thresholds, that are used for opportunistic maintenance. When a maintenance occurs, the first opportunistic threshold is defined to select the non-disassembled components (with only economic dependence) while the second opportunistic threshold is then developed to consider the disassembled components for opportunistic maintenance (with both economic and structural dependences). To evaluate the performance of the proposed opportunistic maintenance policy, a cost model is developed. Particle swarm optimization algorithm is then implemented to find the optimal decision variables. Finally, the proposed opportunistic maintenance policy is illustrated through a conveyor system to show its feasibility and added value in maintenance optimization framework
Quitin, François. "Channel modeling for polarized MIMO systems". Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209951.
Texto completoThe PIPO model is a statistical channel model for tri-polarized to tri-polarized communication systems. A tri-polarized antenna system is a tranceiver using three perpendicular antennas. The aim of the PIPO channel model is to have a model that has a simple mathematical structure, so it can be used for solving precoding equations or capacity calculations. Although the PIPO model has a very simple structure, it takes the following parameters into account: coherent channel component, cross-polar channel power imbalance, inter-channel correlation, short- and long-scale time variance.
Experimental measurements are used to parameterize the model. It is shown how the model parameters are extracted from experimental measurements, and the results are analyzed to allow further simplification of the model.
The PDD model, on the other hand, is a geometry-based stochastic channel model. It models the channel as a sum of clusters, where each cluster consists of groups of multipath components (MPCs). The PDD model includes two novelties that will be developed in detail in this thesis.
- The model considers polarization on a per-cluster basis. This permits to have a more accurate description of the polar-angular spectrum.
- The diffuse multipath component (DMC) is included by considering a diffuse component for each cluster. The diffuse cluster component is then modeled as the sum of a set of diffuse MPCs.
The model is specified in detail, and it is shown how the model can be generated.
Experimental measurements were carried out to parameterize the model. A new extraction technique for extracting the specular-diffuse clusters from the measurements is proposed. This technique is based on joint clustering of the specular MPCs and the bins of the diffuse component. The experimental results are analyzed, and superimposed with environment information to gain further insight into the physical aspects of clustered propagation.
Finally, both models are validated. Several validation metrics are introduced, and their pertinence in the context of polarized MIMO systems is highlighted. Both models are successfully validated, and the advantages and limitations of each models are investigated.
Cette thèse traite des modèles de canal pour systèmes sans-fils multi-antennes polarisés. Des systèmes multi-antennes polarisés sont des systèmes qui utilisent des antennes polarisées perpendiculairement co-localisées à la station de base et au terminal mobile, dans le but de bénéficier de la diversité de polarisation. De tels systèmes peuvent bénéficier des avantages des systèmes MIMO tout en diminuant l'encombrement des équipements. Deux modèles seront présentés dans cette thèse. Le premier est le modèle Polarized-Input Polarized-Output (PIPO), le second est le modèle Polarized-Diffuse-Directional (PDD).
Le modèle PIPO est un modèle statistique pour des systèmes de communication tri-polaire à tri-polaire. Un système tri-polaire est un émetteur ou un récepteur qui utilise trois antennes perpendiculaires. Le but du modèle de canal PIPO est d'avoir un modèle qui a une structure mathématique simple, afin qu'il puisse être utilisé pour résoudre des équations de précodage ou des calculs de capacité. Malgré la structure simple du modèle PIPO, il tient compte des paramètres suivants: la composante cohérente du canal, les différences de puissance entre canaux cross-polaires, la corrélation entre canaux, les variations à courte et à longue échelle de temps. Des mesures expérimentales ont été réalisées afin de paramétriser le modèle. Les techniques pour extraire les paramètres du modèle des mesures expérimentales sont présentées, et les résultats sont analysés afin de permettre une simplification supplémentaire du modèle.
Le modèle PDD, quant à lui, est un modèle de canal stochasique-géométrique. Il modélise le canal comme une somme de clusters, où chaque clusters est composé d'un groupe de chemins multi-trajets. Le modèle PDD inclut les deux nouveautés suivantes qui seront développées en détail dans cette thèse.
- Le modèle considère une polarisation par cluster. Ceci permet d'avoir une description plus exacte du spectre angulaire-polaire.
- La composante diffuse est prise en compte en incluant une composante diffuse pour chaque cluster. La composante diffuse d'un cluster est alors modelisée comme une somme de multi-trajets diffus.
Le modèle est spécifié en détail, et il est présenté comment le modèle peut être généré. Des mesures expérimentales ont été faites afin de paramétriser le modèle. Une nouvelle technique d'extraction est proposée pour extraire les clusters spéculaires-diffus. Cette technique est basée sur le clustering conjoint des multi-trajets spéculaires et des "bins" de la composante diffuse. Les résultats expérimentaux sont analysés, et superposés avec l'information de l'environnement de mesure afin d'avoir une connaissance accrue des aspects physiques de la propagation par clusters.
Finalement, les deux modèles sont validés. Plusieurs métriques de validations sont introduites, et leur pertinence dans le cadre des systèmes MIMO polarisés est mis en avant. Les deux modèles sont validés avec succès, et les avantages et limitations de chaque modèle sont investigués.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Tsormpatzoglou, Andreas. "Caractérisation et modélisation des composants MOS à multiples grilles nanométriques". Grenoble INPG, 2009. http://www.theses.fr/2009INPG0143.
Texto completoThe subject of the PhD is focused on theoretical and experimental studies ofnanoscale multi-gate Metal Oxide Semiconductor Field Effect Transistors. The theoretical part is orientated towards the derivation of analytical expressions for the potential distribution within the channel of the transistors, from which characteristic parameters ofthe transistors are derived. The final aim of the work is to obtain analytical compact expressions for the drain current, valid in aH regions of operation. First, symmetrical Double-Gate MOSFETs are studied, whereas the study of all other types of multi-gate MOSFETs (triple-gate and gate-all-around) is based on the derived model of DG MOSFETs. For the experimental part, the transfer characteristics of single-FinFETs and 5-FinFETs were measured at room temperature. For analysis of the experimental data, numerical simulations were performed to verify the theoretical speculations and optimize the device performance
Belhadj, Taher Aymen. "Etude théorique et expérimentale de composants innovants à fibres optiques multiples". Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0036/document.
Texto completoThese research works presented in this manuscript aim at designing, simulate, manufacture and characterizing the modal converter based microstructured air-silica cane. This function represents a key element for modal multiplexers and chromatic dispersion compensators. The proposed component is based on a tapered microstructured air-silica cane « taper » which constitutes a transition between the two different fibers. The conversion is done through the excitation of a particular mode in a multimode or few mode fibers from a standard fiber. In the tapered structures, the understanding of the different theories involving the coupling between the different modes was yet necessary. A thorough study is carried to analyze the phenomenon of coupling and study the adiabatic criterion. This component is developed around an existing manufacturing technology at XLIM which based in the technique « stack and draw». Finally, we validate numerically and experimentally that principle. We succeed to excite the fundamental mode and higher order modes in a multimode fiber
Nguyen, Van-Thai. "AI-based maintenance planning for multi-component systems considering different kinds of dependencies". Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0070.
Texto completoMaintenance planning for systems consisting of multiple components has still been a challenging problem. Particularly, mathematically describing dependencies between components is usually a complicated task, however, omitting component dependencies in maintenance modeling might result in suboptimal plans. Moreover, the number of maintenance decision variables needed to be optimized increases rapidly in the number of components, causing computational expense for optimization algorithms.To face these issues, this PhD aims to propose an artificial-intelligence-based maintenance optimization approach allowing to consider different kinds of dependencies between components (i.e., economic, stochastic, and structural dependence). Particularly, the maintenance approach integrates a deep maintenance cost model, that allows to compute maintenance costs at system level without requiring individual costs at component level (e.g., setup costs, labor costs and costs of maintaining each component), into the framework of multi-agent deep reinforcement learning, which can be applicable for large sequential decision-making problems, to optimize maintenance decisions. Moreover, a novel degradation interaction model for discrete- state components is also developed and then integrated into the proposed maintenance approach. Numerical studied are conducted on multi-component systems with different configurations under different observability scenarios to investigate the performance and the advantage as well as limits of the proposed maintenance approach
Salmi, Nabila. "Analyse de performances des systèmes basés composants". Chambéry, 2008. http://www.theses.fr/2008CHAMS029.
Texto completoSoftware and hardware industry is being more and more oriented to component based design of systems. The aim of such design is to reduce development cost and time by reuse of components, and to achieve high degree of maintainability, extensibility and dynamics. Ensuring correctness and analysis of these component based systems (CBS) seems to be an important matter, even qualitative or quantitative analysis. In this optic, we develop, in this thesis, a new method allowing to perform a qualitative and quantitative analysis of a CBS. The main benefit of our method is to exploit the compositional architecture of such systems in order to reduce the complexity of analysis (computation time and memory savings), and to allow thus the analysis of important state spaces. This approach starts from the definition of the component architecture of a CBS, and models systematically and adequately this CBS in order to apply a structured method for performance analysis of. The global system. The components are modeled with a high level model, the Stochastic Well-formed Net, widely used for performance evaluation of complex systems partially or totaly symmetrical. Two main kinds of interaction between components are considered : communication by service invocation and event based communication. In order to reduce analysis complexity, the structured analysis of a CBS is based on a tensorial descrition of the generato of the underlying Markov chain. Case studies illustrate our approach
Collet, Timothé. "Méthodes optimistes d’apprentissage actif pour la classification". Electronic Thesis or Diss., Université de Lorraine, 2016. http://www.theses.fr/2016LORR0084.
Texto completoA Classification problem makes use of a training set consisting of data labeled by an oracle. The larger the training set, the best the performance. However, requesting the oracle may be costly. The goal of Active Learning is thus to minimize the number of requests to the oracle while achieving the best performance. To do so, the data that are presented to the oracle must be carefully selected among a large number of unlabeled instances acquired at no cost. However, the true profitability of labeling a particular instance may not be known perfectly. It can therefore be estimated along with a measure of uncertainty. To Increase the precision on the estimate, we need to label more data. Thus, there is a dilemma between labeling data in order to increase the performance of the classifier or to better know how to select data. This dilemma is well studied in the context of finite budget optimization under the name of exploration versus exploitation dilemma. The most famous solutions make use of the principle of Optimism in the Face of Uncertainty. In this thesis, we show that it is possible to adapt this principle to the active learning problem for classification. Several algorithms have been developed for classifiers of increasing complexity, each one of them using the principle of Optimism in the Face of Uncertainty, and their performances have been empirically evaluated
Quinton, Sophie. "Design, vérification et implémentation de systèmes à composants". Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00685854.
Texto completoRoméo, Fabien. "Administration de composants logiciels pour systèmes sans fil". Pau, 2007. http://www.theses.fr/2007PAUU3012.
Texto completoA major trend in wireless systems is the design of their software as an assembly of components. Components are interconnected through their interfaces, while hiding their implementations in order to increase their reuse and to allow to be deployed by third parties. Deployment occurs on various and sundry devices such as mobile phones, PDAs, set-top boxes, and so on. Owing to the fact that deployment environments are different from development environments, abnormal behaviors and/or misuses occur and, consequently, call for remote administration. In this perspective, we designed an architecture for monitoring and controlling the behavior of wireless software components. This behavior is described by UML 2 state machines, which are directly executed on the wireless system and replicated on the administration system. Management policies based on the components' states can thus be defined and enforced. Our proposal has been evaluated and implemented in the WMX (Wireless Management eXtensions) technology, which provides the necessary facilities to build both the manageable software components in a wireless system and their behavioral managers in an administration system
Nguyen, Thanh-Hung. "Vérification Constructive des Systèmes à base de Composants". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENM020.
Texto completoThe goal of the thesis is to develop theory, methods and tools for the compositional and incremental verification for component-based systems. We propose a compositional verification method for proving safety properties. The method is based on the use of two kinds of invariants: component invariants which express local aspects of systems and interaction invariants which characterize global constraints induced by synchronizations between components. We provide efficient methods for computing these invariants. We also propose a new technique that takes the incremental design of the system into account. The integration of verification into design process allows to detect an error as soon as it appears. Moreover, the technique helps to avoid redoing all the verification process by reusing intermediate verification results. It takes advantage of the system structure for coping with complexity of the global verification and therefore, reduces significantly the cost of verification in both time and memory usage. The methods have been implemented in D-Finder tool-set. The experimental results obtained on non trivial examples and case studies show the efficiency of our methods as well as the capacity of D-Finder
Nguyen, Thanh-Hung. "Vérification Constructive des Systèmes à base de Composants". Phd thesis, Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00485933.
Texto completoZouine, Younes. "Contribution par la simulation système à l'étude des contraintes des composants optoélectroniques sur la transmission optique utilisant la technique CDMA". Limoges, 2005. http://aurore.unilim.fr/theses/nxfile/default/a2542528-1671-45c8-9ce8-76ef441c7766/blobholder:0/2005LIMO0059.pdf.
Texto completoThe CDMA technique (Code Division Multiple Access) is widely used in the radio cellular networks (3G). In the recent years, there has been a tendency towards the use of this technique in fibre-optic multiple access networks. This is mainly because of the large available bandwidth of the optical fibre. Associated with DWDM, this technique would indeed allow a significant increase in the number of users in the local area network without increasing in the number of fibres in the core network. It would be accompanied by a drastic cost decrease of the bit/km. This type of study is governed by the constraints bound to signal processing and the component performances. The research reported in this thesis, consists in an investigation through system simulations including the imposed constrains of the components and optoelectronic functions in response of the needs in local optical network architectures using CDMA applications. The limitations due to emission and reception blocks have been specially studied (laser + modulator, photodiodes, associated high speed electronics,…). In addition, the specific properties of optical fibre (dispersion, attenuation) has been considered in the particular case of optical access local network
Sellami, Noura. "Récepteurs itératifs pour les systèmes MIMO (Multiple-Input Multiple-Input)". Cergy-Pontoise, 2002. http://www.theses.fr/2002CERG0159.
Texto completoIn this work, we studied coded MIMO (multiple-input multiple-output) systems, in particular equalization and decoding methods. We choose to use at the transmitter a system based on spatial multiplexing using BICM (Bit Interleaved Coded Modulation) structure. Because of the presence of interleavers, the optimal receiver, based on joint equalization and decoding, is too complex. In order to achieve a good complexity/performance trade-off, we propose to use an iterative receiver. When the channel is frequency selective, the equalizer has to perform time equalization in addition to spatial one. The optimal equalizer is too complex in this case. In order to achieve a good complexity/performance trade-off, we consider a List-type MAP equalizer which is a sub optimal version of the MAP equalizer based on state reduction and Per Survivor Processing (PSP). In order to fight against error propagation, we propose to use a Whitened Matched Filter which concentrates the channel energy on its first taps. In the last part, we study channel estimation when the MIMO channel is frequency selective. First, we show that channel estimation errors are equivalent to a loss in signal to noise ratio and we provide an approximation of this loss. Then, in order to improve the first channel estimation performed using training sequences, we propose to integrate the EM (Expectation Maximisation) algorithm in our iterative receiver. This study is then extended to CDMA systems
Chefrour, Djalel André Françoise. "Plate-forme de composants logiciels pour la coordination des adaptations multiples en environnement dynamique". [S.l.] : [s.n.], 2005. ftp://ftp.irisa.fr/techreports/theses/2005/chefrour.pdf.
Texto completoBen, Hafaiedh Imane. "Systèmes à base de composants : du design à l'implémentation". Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00573291.
Texto completoAl, Masri Nada. "Modèle d'Administration des Systèmes Distribués à Base de Composants". Phd thesis, INSA de Lyon, 2005. http://tel.archives-ouvertes.fr/tel-00474407.
Texto completoBarros, Tomás. "Spécification et vérification formelles des systèmes de composants répartis". Phd thesis, Université de Nice Sophia-Antipolis, 2005. http://tel.archives-ouvertes.fr/tel-00090718.
Texto completoTurki, Slim. "Des hyperclasses aux composants pour l'ingénierie des systèmes d'information". Phd thesis, Université Joseph Fourier (Grenoble), 2005. http://tel.archives-ouvertes.fr/tel-00067785.
Texto completoLe concept d'hyperclasse est une généralisation du concept de classe. Construite à partir d'un ensemble de classes connexe et complet, une hyperclasse permet d'exprimer des concepts que le niveau de classe n'aurait permis d'exprimer, et se comporte comme une classe : elle dispose d'hyperobjets, d'hyperattributs et d'hyperméthodes, équivalents des concepts d'objet, d'attribut et de méthode pour une classe. Un hyperobjet de l'hyperclasse est formé à partir des objets des classes de l'hyperclasse, atteints par navigation, à partir d'une classe particulière de l'hyperclasse qui est sa classe racine, et en suivant un graphe de navigation. Un hyperattribut de l'hyperclasse est un attribut de l'une de ses classes. Une hyperméthode est une méthode associée à l'hyperclasse qui peut avoir comme opérandes des hyperattributs, des hyperobjets, d'autres hyperméthodes de l'hyperclasse, les classes de l'hyperclasse, leurs objets et leurs méthodes de classes. Le concept d'hyperclasse offre une forme d'indépendance entre la structure du SI et ses traitements.
Un composant de SI est une entité autonome et cohérente, dans un modèle de SI, qui regroupe les représentations des espaces informationnel et opérationnel associés à une zone de responsabilité. Il est défini à partir d'une hyperclasse, d'un ensemble de transactions et d'un ensemble de règles d'intégrité du SI. La notion de transaction est associée à une activité productrice ou consommatrice d'informations dans un processus de prise de décision. Les règles d'intégrité sont définies sur un SI pour garantir sa cohérence durant son exploitation.
Les concepts d'hyperclasse et de composant de SI sont munis d'ensembles complets d'opération d'évolution. Ils sont définis indépendamment des méthodes, des langages et des technologies dans lesquelles le SI est implanté.
Le cadre conceptuel que nous proposons permet notamment de prendre en charge les situations de recouvrement de composants de SI, leur évolution, l'évolution du SI et ses répercussions sur ses composants.
Youssef, Lilia. "Construction de systèmes répartis sécurisés à base de composants". Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00721746.
Texto completoNazarpour, Hosein. "Surveillance de systèmes à composants multi-threads et distribués". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAM027/document.
Texto completoComponent-based design is the process leading from given requirements and a set of predefined components to a system meeting the requirements. Components are abstract building blocks encapsulating behavior. They can be composed in order to build composite components. Their composition should be rigorously defined so that it is possible to infer the behavior of composite components from the behavior of their constituents as well as global properties from the properties of individual components. It is, however, generally not possible to ensure or verify the desired property using static verification techniques such as model-checking or static analysis, either because of the state-space explosion problem or because the property can only be decided with information available at runtime (e.g., from the user or the environment). Runtime Verification (RV) is an umbrella term denoting the languages, techniques, and tools for the dynamic verification of system executions against formally-specified behavioral properties. In this context, a run of the system under scrutiny is analyzed using a decision procedure: a monitor. Generally, the monitor may be generated from a user-provided specification (e.g., a temporal-logic formula, an automaton), performs a step-by-step analysis of an execution captured as a sequence of system states, and produces a sequence of verdicts (truth-values taken from a truth-domain) indicating specification satisfaction or violation.This thesis addresses the problem of runtime monitoring multi-threaded and distributed component-based systems with multi-party interactions (CBSs). Although, neither the exact model nor the behavior of the system are known (black box system), the semantic of such CBSs can be modeled with labeled transition systems (LTSs). Inspiring from conformance testing theory, we refer to this as the monitoring hypothesis. Our monitoring hypothesis makes our approach oblivious of (i) the behavior of the CBSs, and (ii) how this behavior is obtained. We consider a general abstract semantic model of CBSs consisting of a set of intrinsically independent components whose interactions are managed by several schedulers. Using such an abstract model, one can obtain systems with different degrees of parallelism, such as sequential, multi-threaded and distributed systems. When monitoring concurrent (multi-threaded and distributed) CBSs, the problem that arises is that a global state of the system is not available at runtime, since the schedulers execute interactions even by knowing the partial state of the system. Moreover, in distributed systems the total ordering of the execution of the interaction is not observable. A naive solution to these problems would be to plug in a monitor which would however force the system to synchronize in order to obtain the sequence of global states as well as the total ordering of the executions at runtime Such a solution would defeat the whole purpose of having concurrent executions and distributed systems. We define two approaches for the monitoring of multi-threaded and distributed CBSs. In both approaches, we instrument the system to retrieve the local events of the schedulers. Local events are sent to an online monitor which reconstructs on-the-fly the set of global traces that are i) compatible with the local traces of the schedulers, and ii) suitable for monitoring purposes, in a concurrency-preserving fashion
Ayache, Nicolas. "Vérification formelle, compositionnelle at automatique de systèmes de composants". Paris 11, 2010. http://www.theses.fr/2010PA112013.
Texto completoNowadays, critical systems based on components are widely used and require a maximal level of trust. Formal methods such as Model-Checking are used to guarantee crucial properties, with a high level of automation. However, Model-Checking suffers from combinatorial explosion when the size of the system becomes too big. This thesis defines a framework for high level description, where verification accompanies the modelisation of the system, and limits the combinatorial explosion problem with a compositional verification of the system. Our approach is based on observer systems. They are executed in parallel of the studied system without interfering on its global behavior, and allow the expression of system properties. The compositional aspect of the verification comes from the possibility to safely replace a part of or a whole system by another one. This is done through the conjoined use of Model-Checking and Abstract Interpretation, which assure the computation of a subset of the behaviors of the system. When Abstract Interpretation introduces approximations, observers can distinguish states that would have been joined otherwise to bring the needed precision. They guide the analysis and are described by the user who explicitly specifies instants of observation. This framework is adapted to the conception flow of a system, where abstractions and refinements are intensively used. For experimental purposes, we developed the SystemD language, resembling SystemC, that integrates the description, the specification and the verification of a system, and stays close to the engineering world
Flamez, Claire. "Systèmes à deux composants et virulence de Yersinia pseudotuberculosis". Lille 2, 2007. http://www.theses.fr/2007LIL2S003.
Texto completoYersinia pseudotuberculosis is a bacterium which colonizes a range of ecosystems, notably the intestine (the ileo-caecal junction) in humans and various other animals, in which it induces lesions. Very rapid adaptation when confronted with a changing (and generally hostile) environment is essential for survival of the bacterium. To this end, a number of pathways enable the bacterium to interact with external signals. One of the most effective involves two-component systems. The prototype is constituted by a membrane-located histidine kinase (sensing changes in the environment) coupled to a cytoplasmic response regulator capable of acting on the transcription of a set of target genes referred to as a regulon. Once the stimulus has been sensed, the sensor phosphorylates itself and then transfers the phosphate group to the coupled response regulator. This reaction induces a cellular response: two bacterial proteins thus create a circuit which converts an external danger signal into an appropriate gene transcription response. In silico analysis of the Y. Pseudotuberculosis genome has revealed the presence of 24 two-component regulatory systems, together with one orphan sensor (i. E. Lacking a partner) and three orphan regulators. Following inactivation of each of the response regulators via reverse genetics, we sought to determine the ability of the resultant 27 mutants to survive in vitro when confronted with the various types of stress encountered by the bacterium in the digestive tube. Ten showed levels of resistance to low pH and/or high osmotic pressure, oxidative stress, the presence of bile or anti-microbial peptides which differed from those of the wild type. However, only 4 were less virulent when administered per os in mice: phoP, rstA-like, yfhA-like and above all ompR. Bearing in mind the limitations of our experimental models, a small number of two-component systems thus appear to influence the virulence of Y. Pseudotuberculosis. Characterization of their respective regulons should reveal the genes involved in the bacterium's as yet poorly understood pathogenic ability
Gault, Sophie. "Conception et optimisation de systèmes de communications à porteuses multiples". Paris 11, 2005. http://www.theses.fr/2005PA112291.
Texto completoThis work is part of the French RNRT project IDILE. We have entirely conceived a modem dedicated to data transmission over the low voltage network (network protocol, synchronization, access, etc. ). An overall point-multipoint network architecture is also presented. We have derived Cramér-Rao Bounds associated with the joint estimation of the clock frequency offset and the channel. This theoretical study shows that the CRBs decrease in the order of O(1/N^3) and O(1/N) respectively, where N is the training sequence length. Moreover, the asymptotic expressions give guidelines for training sequence design. And if we compare its performance with the CRB, our clock frequency offset estimator makes a good compromise between performance and complexity. The last part of this thesis deals with resource and power attribution in a wireless multi-cell OFDMA context, and the constraint is to both satisfy the bitrates requests and minimize the total emitted power in the downlink. We use Rayleigh channels and the base station only knows the mean gain-to-noise ratios of each user. This optimization problem is solved using Lagrange multipliers. The mean rate required in the cell appears as a central parameter in the obtained expressions. Finally, the major result is that in the multi-cell context, the attribution algorithm converges if this mean required rate is below a given threshold
Blackburn, Elizabeth. "Observations de paramètres d'ordre multiples dans les systèmes d'électrons 5ƒ". Université Joseph Fourier (Grenoble), 2005. http://www.theses.fr/2005GRE10226.
Texto completoIn this thesis, multiple order parameters originating in the same electronic system are studied. The multi-k magnetic structures, where more than one propagation wavevector, k, is observed in the same volume, are considered as prototypical models. The effect of this structure on the elastic and inelastic response is studied. In cubic 3-k uranium rocksalts, unexpected elastic diffraction events were observed at positions in reciprocal space where the structure factor should have been zero. These diffraction peaks are identified with correlations between the (orthogonal) magnetic order parameters. The 3-k structure also affects the observed dynamics; the spin-wave fluctuations in uranium dioxide as observed by inelastic neutron polarization analysis can only be explained on the basis of a 3-k structure In the antiferromagnetic superconductor UPd2Al3 the magnetic order and the superconducting state coexist, and are apparently generated by the same heavy fermions. The effect of an external magnetic field on both the normal and superconducting states is examined. In the normal state, the compound displays Fermi-liquid-like behaviour. The inelastic neutron response is strongly renormalized on entering the superconducting state, and high-precision measurements of the low-energy transfer part of this response confirm that the superconducting energy gap has the same symmetry as the antiferromagnetic lattice
Ghaffar, Rizwan. "Atténuation d'interférence dans les systèmes multi-antennaires". Paris, Télécom ParisTech, 2010. http://www.theses.fr/2010ENST0030.
Texto completoAchieving enhanced spectral efficiency and increased reliability are the leading objectives of upcoming wireless systems. In the pursuit of these objectives, it is imperative to devise strategies taking into account the practical constraints so that the ensuing solutions are implementable in the real world. Our focus in this thesis is therefore on the practical communication systems. In the first part of the thesis, we consider low dimensional MIMO systems and propose a low complexity intelligent receiver structure for such systems. This receiver is based on the matched filter (MF) outputs and it successfully reduces one complex dimension of the system. We compare the proposed receiver with MMSE receiver and show that the proposed receiver is characterized by full diversity whereas MMSE receiver suffers from a loss of diversity. Moreover the proposed receiver has a coding gain whereas MMSE suffers from a coding loss. In the second part of the thesis, we look at interference suppression for the cell-edge users in cellular systems. We question the conventional Gaussian assumption for the interference in such scenario and emphasize that this interference has a structure that can be exploited in the detection process. In the last part of the thesis, we consider multi-user (MU) MIMO mode in long term evolution (LTE) systems. We propose a precoding strategy for low resolution LTE precoders which encompass geometrical interference alignment at the base station followed by the exploitation of the residual interference structure by the users
Diallo, Aliou. "Systèmes multi-antennes pour diversité et MIMO". Nice, 2007. https://tel.archives-ouvertes.fr/tel-00454612.
Texto completoThe high data rates required in modern communication can be achieved by multiplying the radiating element involved in the broadcast and in the reception of the wireless link. This solution is called MIMO (Multiple Input and Multiple Output). Also, to reduce the deep fading caused by the multi-path propagating environment, the diversity technique which consists to place one antenna in the broadcast and several antennas in the reception can be used. However, the integration of several efficient antennas on the printed circuit board (PCB) of a mobile phone is a new challenge for antenna researchers. The main goal remains to keep a high isolation between these radiators, otherwise, the diversity gain and the channel capacity of the system can drastically be reduced. The aim of this thesis is to demonstrate the possibility to integrate two closely spaced quarter-wavelength resonators on a small PCB, with high isolation and high total efficiencies when using a neutralization effect between the radiators. However, these two Planar Inverted-F Antennas (PIFAS) were not operating in the same frequency band (DCS and UMTS). This work has been further extended with the successful implementation of this technique to a multi-antennas system operating in the same UMTS band. Several multi-antenna handsets have been designed. Their performance in diversity and MIMO are measured in a reverberation chamber to Göteborg, and in a indoor and outdoor environments to Helsinki
Sy, Ousmane. "Spécification comportementale de composants CORBA". Toulouse 1, 2001. http://www.theses.fr/2001TOU10035.
Texto completoThe thesis proposes three contributions. A formalism for the behavioural specification of CORBA components : the Cooperative Objects CORBA Extension (COCE); a case study : the behavioural specification of the OMG's COS Event Service; an environment for the behavioural specification of CORBA components, named Petshop
Romenska, Yuliia. "Composants abstraits pour la vérification fonctionnelle des systèmes sur puce". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAM019/document.
Texto completoThe work presented in this thesis deals with modeling, specification and testing of models of Systems-on-a-Chip (SoCs) at the transaction abstraction level and higher. SoCs are heterogeneous: they comprise bothhardware components and processors to execute embedded software, which closely interacts with hardware.SystemC-based Transaction Level Modeling (TLM) has been very successful in providing high-level executablecomponent-based models for SoCs, also called virtual prototypes (VPs). These models can be used early in thedesign flow for the development of the software and the validation of the actual hardware. For SystemC/TLMvirtual prototypes, Assertion-Based Verification (ABV) allows property checking early in the design cycle,helping to find bugs early in the model and to save time and effort that are needed for their fixing. TL modelscan be over-constrained, which means that they do not represent all the behaviors of the hardware, and thus,do not allow detection of some malfunctions of the prototype. Our contributions consist of two orthogonal andcomplementary parts: On the one hand, we identify sources of over-constraints in TL models appearing due tothe order of interactions between components, and propose a notion of loose-ordering which allows to removethese over-constraints. On the other hand, we propose a generalized stubbing mechanism which allows the veryearly simulation with SystemC/TLM virtual prototypes.We propose a set of patterns to capture loose-ordering properties, and define a direct translation of thesepatterns into SystemC monitors. Our generalized stubbing mechanism enables the early simulation with Sys-temC/TLM virtual prototypes, in which some components are not entirely determined on the values of theexchanged data, the order of the interactions and/or the timing. Those components have very abstract speci-fications only, in the form of constraints between inputs and outputs. We show that essential synchronizationproblems between components can be captured using our simulation with stubs. The mechanism is generic;we focus only on key concepts, principles and rules which make the stubbing mechanism implementable andapplicable for real, industrial case studies. Any specification language satisfying our requirements (e.g., loose-orderings) can be used to specify the components, i.e., it can be plugged in the stubbing framework. We providea proof of concept to demonstrate the interest of using the simulation with stubs for very early detection andlocalization of synchronization bugs of the design
Chang, Hervé. "Négociation de contrats dans les systèmes à composants logiciels hiérarchiques". Phd thesis, Université de Nice Sophia-Antipolis, 2007. http://tel.archives-ouvertes.fr/tel-00782493.
Texto completoEwann, Fanny. "Analyse fonctionnelle de systèmes à deux composants de Mycobacterium tuberculosis". Lille 2, 2003. http://www.theses.fr/2003LIL2MT23.
Texto completoErddalane, Abdelâli. "Réactivité des états excités de systèmes photoamorceurs à trois composants". Mulhouse, 1994. http://www.theses.fr/1994MULH0327.
Texto completoHamouche, Rédha. "Modélisation des systèmes embarqués à base de composants et d'aspects". Evry-Val d'Essonne, 2004. http://www.theses.fr/2004EVRY0015.
Texto completoThis thesis work address embedded systems design. It proposes a modelling approach that faces the complexity of theses systems, reduces their design time and covers their different and multiple application domains (Models of Computation). This approach, called ModelJ, is based on two main paradigms recently appeared in software engineeriing : the component and the aspect paradigms. The component paradigm addresses the system complexity and improves reusability where as the aspect paradigm deals with the flexibility and adaptability of system descriptions. The proposed approach defines a metamodel and a framework. The metamodel provides a set of reusable and modular abstract models for describing the embedded system in a language-independent way. The framework is the software environment that implements the defined metamodel and allows to model, develop and simulate the system
Oudot, Emilie. "Contributions à la vérification incrémentale des systèmes temporisés à composants". Besançon, 2006. http://www.theses.fr/2006BESA2051.
Texto completoWe are interested in the verification by model-checking of component-based timed systems. The state-space explosion problem of the model-checking makes the method difficult to apply on large-sized systems. A way out is to use incremental development methods, such as refinement or integration of components. From a verification point of view, these methods must provide the possibility to check properties at each step of the incremental process (instead of performing the verification on the complete model of the system). This framework is applicable only if already established properties are preserved by the development. Tau-simulations are a way to guarantee this preservation. This document presents two tau-simulations, for timed systems: a timed tau-simulation which preserves safety properties, and a divergence-sensitive and stability-respecting (DS) timed tau-simulation, which preserves all MITL properties. In compositionnal frameworks, the following properties of the tau-simulations w. R. T. Composition operators are essential: compositionnality, compatibility and composability. They show the interest of the tau-simulations for incremental development. Thus, we study these properties w. R. T. An operator à la CSP, and an operator à la CCS. To show the interest in practice of these simulations, we developped the prototype VeSTA. It focuses on an incremental development of timed systems by integration of components. It allows to guarantee the preservation of MITL properties by checking the DS timed tau-simulation. Moreover, the design of VeSTA was inspired by the tool Open-Kronos, to make possible the connection to the verification platform Open-Caesar
Skiba, Karima. "Modélisation de systèmes intégrés à base de composants électroniques virtuels". Grenoble INPG, 2002. http://www.theses.fr/2002INPG0088.
Texto completoDuong, Phuong Quynh. "La tolérance aux fautes adaptable pour les systèmes à composants". Grenoble INPG, 2003. http://www.theses.fr/2003INPG0112.
Texto completoFrancisco, Martín Rubén de. "Optimisation de la performance des systèmes MIMO avec connaissance partielle du canal". Paris, ENST, 2008. http://pastel.archives-ouvertes.fr/pastel-00003718.
Texto completoMultiple-input multiple-output (MIMO) wireless communication systems have the potential to offer high data rates as well as link reliability. The feasibility of these systems in future mobile communication standards depends on the ability to provide high rates with a reduced amount of channel state information at the transmitter (CSIT), due to limited resource availability on the feedback link. This thesis addresses the problem of optimizing MIMO systems with partial CSIT. On the one hand, we provide methods for obtaining CSIT. On the other hand, we propose techniques to exploit the available sources of CSIT to optimize the system performance. In the first part, point-to-point MIMO channels are considered for the purpose of error rate minimization. Linear precoding techniques are proposed to enhance the performance of space-time coded (STC) MIMO systems, by appropriately combining information on the channel mean and covariance. In the second part of this thesis, we focus on sum-rate performance optimization in MIMO broadcast channels with limited feedback. Low-complexity cross-layer approaches are proposed for systems with joint linear beamforming and multiuser scheduling, optimizing the following parts in the MIMO communications system: linear beamforming techniques, scheduling algorithms, feedback strategies and feedback quantization techniques. A design framework for channel quality information (CQI) feedback design is proposed, based on an estimate on each user's signal-to-interference-plus-noise ratio (SINR). As we show, the system performance can be enhanced by using simple channel quantization strategies combined with optimized linear beamforming techniques
Collet, Timothé. "Méthodes optimistes d’apprentissage actif pour la classification". Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0084/document.
Texto completoA Classification problem makes use of a training set consisting of data labeled by an oracle. The larger the training set, the best the performance. However, requesting the oracle may be costly. The goal of Active Learning is thus to minimize the number of requests to the oracle while achieving the best performance. To do so, the data that are presented to the oracle must be carefully selected among a large number of unlabeled instances acquired at no cost. However, the true profitability of labeling a particular instance may not be known perfectly. It can therefore be estimated along with a measure of uncertainty. To Increase the precision on the estimate, we need to label more data. Thus, there is a dilemma between labeling data in order to increase the performance of the classifier or to better know how to select data. This dilemma is well studied in the context of finite budget optimization under the name of exploration versus exploitation dilemma. The most famous solutions make use of the principle of Optimism in the Face of Uncertainty. In this thesis, we show that it is possible to adapt this principle to the active learning problem for classification. Several algorithms have been developed for classifiers of increasing complexity, each one of them using the principle of Optimism in the Face of Uncertainty, and their performances have been empirically evaluated
Kharrat, Fatma. "Techniques adaptatives et classification pour les canaux à antennes multiples". Paris, ENST, 2006. http://www.theses.fr/2006ENST0041.
Texto completoThis thesis report focuses on wireless communication systems with multiple transmit and multiple receive antennas. At first, we study the performance of such systems assuming a spatial multiplexing scheme at the transmitter and an ML detection at the receiver. We derive an accurate approximation for the conditional error probability on a quasi static channel. This approximation is computed when distinct modulations are applied on the transmit antennas and for any MIMO channel configuration. Then, we outline some adaptive techniques for MIMO systems: adaptive modulation and antenna selection. The first one adjusts the modulations on transmit antennas according to the channel conditions in order to maximize the spectral efficiency while satisfying a constraint on error probability. The second technique selects the set of active antennas to optimize the chosen selection criterion (e. G. Maximize the capacity, etc) providing a channel estimation. Both adaptive techniques need a relevant matric to evaluate the MIMO system performance. We propose a new adaptive modulation scheme and antenna selection algorithm where the derived error probability approximation is used as a selection metric. Finally, we consider the quantization of MIMO channels. This quantization, in our terminology classification, allows the partitioning of MIMO channels set into different classes, where each class is identified by a representative. This method could be used for adaptive techniques to find the best adjustable parameters. We describe our MIMO classification algorithm and we illustrate its application for closed-loop MIMO systems, e. G beamforming
Froberger, Kévin. "Caractérisation et modélisation de composants terahertz". Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I102.
Texto completoThe terahertz domain is a frequency range, which interest keeps growing because of its properties. Because of the low energy of the photons, it becomes possible to use it for medical imaging, non destructive testing in the industry or even learn about the celestial objects around us. Its high frequencies also allow to increase the data bit rate, which is currently one of the main point of interest. This PhD thesis is mainly based on this aspect of the terahertz domain even though it is not completly restrained to it. The increase of telecommunication frequencies allows an increase in data rate but requires to find and optimize new sources and antennas. Therefore, simulations of a Uni-Travelling Carrier photodiode (UTC photodiode) structure were done in order to increase its photoresponse. A second part of this thesis is about the design, the fabrication and the characterization of a new kind of antenna which goal is to be broadband and to allow the transmission of signals which frequencies are over 300 GHz. In all its applications, the terahertz domain could be difficiult to grasp because its waves are invisible to the human eye. As a result, it would be useful to develop cameras to see those beams. The last part of the thesis is about the detection of signals at 2.5 THz where we propose two designs of a micro thermo-opto-mechanical system (MEMS). The systems are then fabricated and measured. The final goal would be to be able to use it as a single pixel in a terahertz camera at this frequency
Dumont, Julien. "Optimisation conjointe de l'émetteur et du récepteur par utilisation des a priori du canal dans un contexte MIMO". Marne-la-Vallée, 2006. http://www.theses.fr/2006MARN0310.
Texto completoDhayni, Achraf. "Test intégré pseudo aléatoire pour les composants microsystèmes". Grenoble INPG, 2006. https://tel.archives-ouvertes.fr/tel-00135916.
Texto completoThe growing use of MEMS in life-critical applications has accelerated the need for robust test methods. MEMS have complex failure mechanisms and device dynamics that are most often poorly understood. This is due to their multi-domain nature which makes them inherently complex for both design and test. Manufacturing is in addition complicated by the need of new fabrication steps in particular when System-in-Package (SiP) techniques are used. These packaging techniques enable to have a module that contains highly heterogeneous IP blocks or chips, giving important benefits in terms of time-to-market shortening and miniaturization. However, this poses many test problems. In this area, BIST techniques for analog and mixed-signal circuits have attracted considerable industrial interest for helping reduce increasing test related difficulties. In this thesis we propose a pseudorandom (PR) functional BIST for MEMS. Since the test control is necessarily electrical, electrical test sequences must be converted to the energy domain required by the MEMS. Thus, we propose the use of pseudorandom electrical pulses that have the advantage of being easily generated on-chip and the conversion to the actual energy domain has been demonstrated for different types of MEMS. We show how different types of PR sequences can be exploited within a BIST approach for both linear and nonlinear MEMS. In general, we show that two-level PR sequences are sufficient for testing both linear and nonlinear MEMS. In addition, while two-level PR sequences are sufficient for characterizing linear MEMS, we describe how the use of multilevel PR sequences is necessary for the characterization of nonlinear MEMS. The number of needed levels depends on the order of nonlinearity of the MEMS under test. The output test response is digitized using an existing on-chip self-testable ADC and a digital circuit performs some simple digital signal processing to extract Impulse Response (IR) samples for linear MEMS, or Volterra kernel samples for nonlinear MEMS. Next, these samples (called test signature) are compared with their tolerance ranges and a pass/fail signal is generated by the BIST. We use Monte Carlo simulations to derive the test signature tolerance ranges out of the specification tolerance ranges. Monte Carlo simulations are also used to form the test signature after a sensitivity analysis, and to inject parametric variations to calculate the test metrics and to optimize BIST design parameters, such as the length of the LFSR and the bit precision of digital circuitry. We have applied the PR BIST for MEMS like commercialized accelerometers and microbeams that we have fabricated. Satisfactory experimental results have been obtained
Bouvet, Pierre-Jean. "Récepteurs itératifs pour systèmes multi-antennes". Rennes, INSA, 2005. http://www.theses.fr/2005ISAR0021.
Texto completoLetessier, Jonathan. "Performances théoriques de systèmes MIMO pré-égalisés et applications avec un simulateur de propagation 3D". Brest, 2005. http://www.theses.fr/2005BRES2028.
Texto completoThe MIMO (multiple-input multiple-output) systems are a great interest for the next generation of wireless systems. Indeed, these systems have been developed to increase the theoretical capacity and/or robustness of the traditional systems (mono-antenna) by using space diversity. The framework of this thesis focused around pre-equalized MIMO systems having the channel state information at the transmitter side by information feedback. We expresssed literally the average bit error probabilities (BEP) in the decorrelated Rayleigh channel case for pre-equalized systems WF (WF : capacity maximization), MMSE (minimization of the mean square error), QoS(quality of service between channels), EE (equal error between channels) and max-SNR ( maximization of the signal-to-noise ratio at the receiver side). The resulting BEP curves highlighted that performance improvement is influenced by the total number of antennas, the distribution of the antennas between the transmitter and the receiver, the choice of the parameters of the precoder to be used. A collaboration with the SIC laboratory of Poitiers (France) enabled us of study statistically "realistic" channels produced by their 3-D propagation simulator. We, thus, tested the robustness of the precoders for different indoor configurations in the HIPERLAN/2 frequency band and compared results to those of the Rayleigh case
Tirki, Moncef. "Synthèse d’observateurs pour des classes de systèmes non linéaires". Caen, 2011. http://www.theses.fr/2011CAEN2003.
Texto completoThe work presented in this thesis focuses on the synthesis of observers for classes of nonlinear systems namely the classical observers used for state estimation, unknown input observers and the adaptive observers. At first, we propose a non triangular canonical form of observability characterising a large class of multi-output systems observable for any input. A high gain observer is proposed. The exponential convergence of the proposed observer is detailed and validated in simulation and illustrated through examples. Then, we discuss the synthesis of unknown input observers. A class of systems with unknown inputs is presented. The proposed observer can jointly estimate all the states of the system and all the unknown inputs. The synthesis of this observer is verified under certain sufficient conditions based on those adopted in the absence of unknown inputs. Indeed, numerical simulations illustrate the convergence of the observer. Finally an adaptive observer is proposed for the non triangular canonical form introduced at the beginning of this report. The exponential convergence of the proposed observer is established under a certain condition of persistent excitation which has been given. The performances of this observer are illustrated in simulation through an academic example
Stoicescu, Miruna. "Conception et implémentation de systèmes résilients par une approche à composants". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2013. http://tel.archives-ouvertes.fr/tel-01018621.
Texto completoMorel, Hervé. "Modélisation et simulation des composants et des systèmes électroniques de puissance". Habilitation à diriger des recherches, INSA de Lyon, 1994. http://tel.archives-ouvertes.fr/tel-00731059.
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