Dissertationen zum Thema „Largeur infinie“
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Hajjar, Karl. „A dynamical analysis of infinitely wide neural networks“. Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASM001.
Der volle Inhalt der QuelleNeural networks have had tremendous success in many practical tasks over the last decade, yet the theoretical reasons behind their performance are poorly understood and we lack a proper mathematical theory to rigorously study the properties of those objects. Infinite-width limits of neural networks have recently emerged as a way to shed light on some of the aspects of the problem. In this thesis, we study the infinite-width limit of networks of different depths under a particular scaling often referred to as the ''mean-field'' scaling in the literature. Part of the reason why neural networks are difficult to analyze from a theoretical standpoint is because they are highly non-linear and involve a huge amount of parameters, or weights, (up to hundreds of billions in practice) which interact as they are updated during gradient descent. We investigate the optimization trajectories of the infinite-width limit of neural networks during training in order to exhibit properties of those models in simple settings such as fully-connected networks with one or more hidden layers. This thesis focuses on different aspects of the optimization dynamics of networks in the infinite-width limit: from methods to enable training those models at arbitrary depths to the symmetry properties that can emerge in that limit as well as novel optimization algorithms which adapt the number of neurons in an on-line fashion during training
Mens, Irini-Eleftheria. „Learning regular languages over large alphabets“. Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAM052/document.
Der volle Inhalt der QuelleLearning regular languages is a branch of machine learning, which has been proved useful in many areas, including artificial intelligence, neural networks, data mining, verification, etc. On the other hand, interest in languages defined over large and infinite alphabets has increased in recent years. Although many theories and properties generalize well from the finite case, learning such languages is not an easy task. As the existing methods for learning regular languages depends on the size of the alphabet, a straightforward generalization in this context is not possible.In this thesis, we present a generic algorithmic scheme that can be used for learning languages defined over large or infinite alphabets, such as bounded subsets of N or R or Boolean vectors of high dimensions. We restrict ourselves to the class of languages accepted by deterministic symbolic automata that use predicates to label transitions, forming a finite partition of the alphabet for every state.Our learning algorithm, an adaptation of Angluin's L*, combines standard automaton learning by state characterization, with the learning of the static predicates that define the alphabet partitions. We use the online learning scheme, where two types of queries provide the necessary information about the target language. The first type, membership queries, answer whether a given word belongs or not to the target. The second, equivalence queries, check whether a conjectured automaton accepts the target language, a counter-example is provided otherwise.We study language learning over large or infinite alphabets within a general framework but our aim is to provide solutions for particular concrete instances. For this, we focus on the two main aspects of the problem. Initially, we assume that equivalence queries always provide a counter-example which is minimal in the length-lexicographic order when the conjecture automaton is incorrect. Then, we drop this ``strong'' equivalence oracle and replace it by a more realistic assumption, where equivalence is approximated by testing queries, which use sampling on the set of words. Such queries are not guaranteed to find counter-examples and certainly not minimal ones. In this case, we obtain the weaker notion of PAC (probably approximately correct) learnability and learn an approximation of the target language. All proposed algorithms have been implemented and their performance, as a function of automaton and alphabet size, has been empirically evaluated
Takisaka, Toru. „Large Scale Geometries of Infinite Strings“. Kyoto University, 2018. http://hdl.handle.net/2433/232221.
Der volle Inhalt der QuelleMallik, Mohammed Tariqul Hassan. „Electromagnetic Field Exposure Reconstruction by Artificial Intelligence“. Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDENGSYS/2023/2023ULILN052.pdf.
Der volle Inhalt der QuelleThe topic of exposure to electromagnetic fields has received muchattention in light of the current deployment of the fifth generation(5G) cellular network. Despite this, accurately reconstructing theelectromagnetic field across a region remains difficult due to a lack ofsufficient data. In situ measurements are of great interest, but theirviability is limited, making it difficult to fully understand the fielddynamics. Despite the great interest in localized measurements, thereare still untested regions that prevent them from providing a completeexposure map. The research explored reconstruction strategies fromobservations from certain localized sites or sensors distributed inspace, using techniques based on geostatistics and Gaussian processes.In particular, recent initiatives have focused on the use of machinelearning and artificial intelligence for this purpose. To overcome theseproblems, this work proposes new methodologies to reconstruct EMFexposure maps in a specific urban area in France. The main objective isto reconstruct exposure maps to electromagnetic waves from some datafrom sensors distributed in space. We proposed two methodologies basedon machine learning to estimate exposure to electromagnetic waves. Forthe first method, the exposure reconstruction problem is defined as animage-to-image translation task. First, the sensor data is convertedinto an image and the corresponding reference image is generated using aray tracing-based simulator. We proposed an adversarial network cGANconditioned by the environment topology to estimate exposure maps usingthese images. The model is trained on sensor map images while anenvironment is given as conditional input to the cGAN model.Furthermore, electromagnetic field mapping based on the GenerativeAdversarial Network is compared to simple Kriging. The results show thatthe proposed method produces accurate estimates and is a promisingsolution for exposure map reconstruction. However, producing referencedata is a complex task as it involves taking into account the number ofactive base stations of different technologies and operators, whosenetwork configuration is unknown, e.g. powers and beams used by basestations. Additionally, evaluating these maps requires time andexpertise. To answer these questions, we defined the problem as amissing data imputation task. The method we propose takes into accountthe training of an infinite neural network to estimate exposure toelectromagnetic fields. This is a promising solution for exposure mapreconstruction, which does not require large training sets. The proposedmethod is compared with other machine learning approaches based on UNetnetworks and conditional generative adversarial networks withcompetitive results
Federici, Bruno. „Interactions between large-scale invariants in infinite graphs“. Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/108882/.
Der volle Inhalt der QuelleWinterfeld, Anton. „Large-scale semi-infinite optimization applied to industrial gemstone cutting“. Berlin dissertation.de, 2007. http://www.dissertation.de/buch.php3?buch=5290.
Der volle Inhalt der QuelleMaroulas, Vasileios Budhiraja Amarjit. „Small noise large deviations for infinite dimensional stochastic dynamical systems“. Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1779.
Der volle Inhalt der QuelleTitle from electronic title page (viewed Sep. 16, 2008). " ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Statistics and Operations Research Statistics." Discipline: Statistics and Operations Research; Department/School: Statistics and Operations Research.
He, Ruojun. „Square Coded Aperture: A Large Aperture with Infinite Depth of Field“. University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1418078808.
Der volle Inhalt der QuellePontes, Duff Pereira Igor. „Approximation des systèmes dynamiques à grande dimension et à dimension infinie“. Thesis, Toulouse, ISAE, 2017. http://www.theses.fr/2017ESAE0001/document.
Der volle Inhalt der QuelleIn the engineering area (e.g. aerospace, automotive, biology, circuits), dynamical systems are the basic framework used for modeling, controlling and analyzing a large variety of systems and phenomena. Due to the increasing use of dedicated computer-based modeling design software, numerical simulation turns to be more and more used to simulate a complex system or phenomenon and shorten both development time and cost. However, the need of an enhanced model accuracy inevitably leads to an increasing number of variables and resources to manage at the price of a high numerical cost. This counterpart is the justification for model reduction. For linear time-invariant systems, several model reduction approaches have been effectively developed since the 60’s. Among these, interpolation-based methods stand out due to their flexibility and low computational cost, making them a predestined candidate in the reduction of truly large-scale systems. Recent advances demonstrate ways to find reduction parameters that locally minimize the H2 norm of the mismatch error. In general, a reduced-order approximation is considered to be a finite dimensional model. This representation is quite general and a wide range of linear dynamical systems can be converted in this form, at least in principle. However, in some cases, it may be more relevant to find reduced-order models having some more complex structures. As an example, some transport phenomena systems have their Hankel singular values which decay very slowly and are not easily approximated by a finite dimensional model. In addition, for some applications, it is valuable to have a structured reduced-order model which reproduces the physical behaviors. That is why, in this thesis, reduced-order models having delay structures have been more specifically considered. This work has focused, on the one hand, in developing new model reduction techniques for reduced order models having delay structures, and, on the other hand, in finding new applications of model approximation. The major contribution of this thesis covers approximation topics and includes several contributions to the area of model reduction. A special attention was given to the H2 optimal model approximation problem for delayed structured models. For this purpose, some new theoretical and methodological results were derived and successfully applied to both academic and industrial benchmarks. In addition, the last part of this manuscript is dedicated to the analysis of time-delayed systems stability using interpolatory methods. Some theoretical statements as well as an heuristic are developed enabling to estimate in a fast and accurate way the stability charts of those systems
Xu, Tiange. „Large deviations and invariant measures for stochastic partial differential equations in infinite dimensions“. Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496642.
Der volle Inhalt der QuelleKing, James Allen. „Application of H(infinity) optimal control to large space structures“. Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183649698.
Der volle Inhalt der QuelleBose, Gibin. „Approximation H infini, interpolation analytique et optimisation convexe : application à l’adaptation d’impédance large bande“. Thesis, Université Côte d'Azur, 2021. http://www.theses.fr/2021COAZ4007.
Der volle Inhalt der QuelleThe thesis makes an in-depth study of one of the classical problems in RF circuit design,the problem of impedance matching. Matching problem addresses the issue of transmitting the maximum available power from a source to a load within a frequency band. Antennas are one of the classical devices in which impedance matching plays an important role. The design of a matching circuit for a given load primarily amounts to find a lossless scattering matrix which when chained to the load minimize the reflection of power in the total system.In this work, both the theoretical aspects of the broadband matching problem and thepractical applicability of the developed approaches are given due importance. Part I of the thesis covers two different yet closely related approaches to the matching problem. These are based on the classical approaches developed by Helton and Fano-Youla to study the broadband matching problems. The framework established in the first approach entails in finding the best H infinity approximation to an L infinity function, Փ via Nehari's theory. This amounts to reduce the problem to a generalized eigen value problem based on an operator defined on H2, the Hankel operator, HՓ. The realizability of a given gain is provided by the constraint, operator norm of HՓ less than or equal to one. The second approach formulates the matching problem as a convex optimisation problem where in further flexibility is provided to the gain profiles compared to the previous approach. It is based on two rich theories, namely Fano-Youla matching theory and analytic interpolation. The realizabilty of a given gain is based on the Fano-Youla de-embedding conditions which reduces to the positivity of a classical matrix in analytic interpolation theory, the Pick matrix. The concavity of the concerned Pick matrix allows finding the solution to the problem by means of implementing a non-linear semi-definite programming problem. Most importantly, we estimate sharp lower bounds to the matching criterion for finite degree matching circuits and furnish circuits attaining those bounds.Part II of the thesis aims at realizing the matching circuits as ladder networks consisting of inductors and capacitors and discusses some important realizability constraints as well. Matching circuits are designed for several mismatched antennas, testing the robustness of the developed approach. The theory developed in the first part of the thesis provides an efficient way of comparing the matching criterion obtained to the theoretical limits
HIRET, ARNAUD. „Pilotage robuste d'un missile sur un large domaine de vol synthese et analyse dans le cadre h-infini et lpv“. Paris 11, 1999. http://www.theses.fr/1999PA112260.
Der volle Inhalt der QuelleVouvakis, Marinos N. „A Non-Conformal Domain Decomposition Method for Solving Large Electromagnetic Wave Problems“. The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1125498071.
Der volle Inhalt der QuelleWei, Fajin. „Stochastic Infinity-Laplacian equation and One-Laplacian equation in image processing and mean curvature flows : finite and large time behaviours“. Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7345.
Der volle Inhalt der QuelleTsitsopoulos, Vasileios. „Modelling of buoyant flows associated with large area fires and indirect free convection“. Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/modelling-of-buoyant-flows-associated-with-large-area-fires-and-indirect-free-convection(7e849d5b-6b95-4534-b387-63387f5ff26f).html.
Der volle Inhalt der QuelleTheodoulis, Spilios. „Robust Control in a Nonlinear Context for Large Operating Domains“. Phd thesis, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00352237.
Der volle Inhalt der QuelleCette stratégie est basée sur une pré-compensation (loop shaping) faite à partir des systèmes linéarisés du système non-linéaire autour d'un petit nombre de points de fonctionnement en utilisant des compensateurs de structure simple (e.g. PID), et de plus en utilisant une compensation additionnelle/corrective type retour de sortie H1 statique. Les points de fonctionnement de la deuxième compensation sont calculés à l'aide d'un algorithme de choix de points de synthèse basé sur la connexion des théories de la gap métrique et de la commande H1 par loop shaping. La loi de commande globale non-linéaire séquencée est finalement obtenue en utilisant une interpolation de tous les gains des com-pensateurs impliqués pendant la phase de synthèse.
La méthode proposée ici est validée sur deux exemples d'application : le pilotage autour de l'axe de tangage d'un missile fortement manœuvrant et d'un véhicule de rentrée atmosphérique. Les deux autopilotes sont testés de façon intensive en utilisant des simulations non-linéaires, une analyse Monte Carlo et linéaire à temps figé afin de démontrer leurs excellentes caractéristiques en termes de performance et de robustesse.
Harrat, Ayoub. „Problème de moments avec applications et estimations du spectre discret des opérateurs définis par des matrices infinies non bornées THE QUINTIC COMPLEX MOMENT PROBLEM ASYMPTOTIC EXPANSION OF LARGE EIGENVALUES FOR A CLASS OF UNBOUNDED JACOBI MATRICES“. Thesis, Littoral, 2020. http://www.theses.fr/2020DUNK0563.
Der volle Inhalt der QuelleIn this thesis, we first provide a concrete solution to the, almost all, quintic TCMP (that is, when m = 5). We also study the cardinality of the minimal representing measure. Based on the bi-variate recurrence sequence properties with some Curto-Fialkow's results. Our method intended to be useful for all odd-degree moment problems. Second, we investigate the full moment problem for discrete measures using Vasilescu's idempotent approach based on Λ-multiplicative elements with respect to the associated square positive Riesz functional. We give a sufficient condition for the existence of a discrete integral representation for the associated Riesz functional, which turns to be necessary in bounded shift space case. A particular attention is given to Λ-multiplicative elements, where a total description, for the cases where they are a single point indicator functions, is given. Lastly, We investigate a class of infinite Jacobi matrices which define unbounded self-adjoint operators with discrete spectrum. Our purpose is to establish the asymptotic expansion of large eigenvalues and to compute two correction terms explicitly. This method works in general for band matrices but Jacobi matrices case still much interesting due to applications and explicit expressions obtained for the first correction terms in the asymptotic formula
Mansouri, Mejda. „Observation et commande des systèmes de grande dimension“. Electronic Thesis or Diss., Université de Lorraine, 2012. http://www.theses.fr/2012LORR0303.
Der volle Inhalt der QuelleIn this dissertation, we investigated the problems of the estimation, H∞ filtering and the controller based-observer design for standard large scale systems and for algebro-differentials ones called also singular large scale systems. So, we began to propose methods for decentralized observer design with unknown interconnections for standard and singular systems. We search here to decouple the unknown interconnections and the dynamics of the observation error. The method is based on LMIs approach to find the gain matrix implemented in the observer matrices. The LMI formulation is based on Lyapunov approach and deduced from various bounded lemmas. We propose then, filters that permits to ensure, in addition to the stability, an H∞ performance criteria; we search to attenuate the perturbations effect, supposed unknown but of bounded energy, on the dynamics of the estimation error. We discussed after the study of interconnected observers for large systems, we have proposed a new method to design a new form of interconnected observers connectively stable. We are interested in the ability of a such observer to be robustly stable towards uncertainties in the interconnections between sub-observers. Finally, we are interested to the application of the proposed estimation methods to the control purpose. Indeed, in a first step, we propose a decentralized control based on a filter H∞ for a class of large scale standard systems with nonlinear interconnections. Then, Then, we focus our attention on the observer based control for singular systems to search for a control law which ensures an H∞ performance criteria. The approach is an extension of recent works of Kalsi and al. to the case of disturbed large scale systems. One of the main contributions of our work was to propose a new method of control design based on a filter H∞ which generated by using less restrictive conditions than those introduced in the work of Kalsi and al. Thus, we have relaxed the constraint on the distance between the pair of matrices formed by the state matrix and input matrix and the set of pairs of matrices uncontrollable. In addition, we consider the maximization of the bound of the interconnection, which is very important in practice. Our approach is obtained into two steps. The first one consist on calculating the gain state feedback that meets the specifications of the closed loop system. The second one , then we reconstruct this control law using our previous results on the H∞ filtering. The approach has been validated on an example of a system composed of three interconnected electrical machines
Sun, Wen. „A study of interacting stochastic networks : large scale, long time behavior and fluctuations, with applications in communication networks and protein polymerization“. Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS075.
Der volle Inhalt der QuelleThis PhD document is devoted to the analyses of large stochastic networks used to study mathematical models in communication networks and in biology. The first part consists of the analysis of three models used to evaluate the efficiency of duplication and placement algorithms in large distributed systems. These models are represented by large stochastic networks under different scaling regimes assumptions. In Chapter 2, the dynamic of the system can be described with the empirical measure associated to a multi-dimensional transient Markov process. We provide a detailed study of these processes on several fast time scales. Stochastic averaging principles with multiple time scales are investigated in particular. In Chapter 3 and Chapter 4, the interactions have unbounded jump sizes and occur within a limited random set of nodes. We develop a convenient mean field analysis in despite that the associated empirical measures do not have autonomous evolution equations. We also study the long time behavior of the corresponding limiting nonlinear jump diffusions. The second part analyzes two models used to study the variability in the polymerization phenomena occurring in a biological context. In Chapter 5, we investigate the polymerization and fragmentation processes with an assumption of critical nucleus size. A scaling analysis of these stochastic models show that the sharp phase transition and, especially the large variance, observed in the experiments can be explained by these models. In Chapter 6, we provide a functional central limit theorem in the classical (infinite dimensional) stochastic Becker-Döring model
Mansouri, Mejda. „Observation et commande des systèmes de grande dimension“. Phd thesis, Université de Lorraine, 2012. http://tel.archives-ouvertes.fr/tel-00808649.
Der volle Inhalt der QuelleGao, Nan. „Observateurs dynamiques et commande des systèmes : application aux systèmes de grande dimension“. Electronic Thesis or Diss., Université de Lorraine, 2015. http://www.theses.fr/2015LORR0081.
Der volle Inhalt der QuelleThe present thesis is the result of research conducted in Longwy, within the department Control, Identification, Diagnosis (CID) of Research Center for Automatic Control of Nancy (CRAN). This thesis investigates the problem of dynamic observer (full- and reduced-order) and observer-based control design and their applications to large-scale systems. Firstly, a new form of H-infinity dynamic observer is designed for linear systems in the presence of unknown inputs and disturbances. The proposed observer generalizes the existing results on proportional observer and proportional integral observer. The observer design is based on the solution of linear matrix inequalities (LMI). Both continuous-time and discrete-time systems are considered. Thereafter, by inserting the proposed observer into a closed-loop, an observer-based control is presented for uncertain systems in the presence of disturbances. Based on the parameterization of algebraic constraints obtained from the analysis of the estimation error, the control design is derived from the solution of bilinear matrix inequality, by using a two-steps algorithm. Finally, the obtained results have been extended to large-scale systems. A decentralized observer-based control is proposed for large-scale uncertain systems in the presence of disturbances. These systems are composed of several interconnected subsystems of low dimensions, where the interconnections are assumed to be nonlinear and satisfy quadratic constraints
Bel, Haj Frej Ghazi. „Estimation et commande décentralisée pour les systèmes de grandes dimensions : application aux réseaux électriques“. Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0139/document.
Der volle Inhalt der QuelleThis thesis focuses on the decentralized estimation and control for large scale systems. The objective is to develop software sensors that can produce a reliable estimate of the variables necessary for the interconnected nonlinear systems stability analysis. A decomposition of a such large system into a set of n interconnected subsystems is paramount for model simplification. Then, taking into account the nature of the subsystem as well as the interconnected functions, observer-based decentralized control laws have been synthesized. Each control law is associated with a subsystem which allows it to be locally stable, thus the stability of the overall system is ensured. The existence of an observer and a controller gain matrix stabilizing the system depends on the feasibility of an LMI optimization problem. The LMI formulation, based on Lyapunov approach, is elaborated by applying the DMVT technique on the nonlinear interconnection function, assumed to be bounded and uncertain. Thus, non-restrictive synthesis conditions are obtained. Observer-based decentralized control schemes have been proposed for nonlinear interconnected systems in the continuous and discrete time. Robust Hinfini decentralized controllers are provided for interconnected nonlinear systems in the presence of perturbations and parametric uncertainties. Effectiveness of the proposed schemes are verified through simulation results on a power systems with interconnected machines
Jakel, Roland. „Das neue Kontaktmodell mit endlicher Reibung in Creo Simulate 3.0 : Theorie und Anwendung ; Vergleich mit dem reibungsfreien und unendlich reibungsbehafteten Kontaktmodell“. Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-206817.
Der volle Inhalt der QuelleThe presentation describes the underlying theory and software functionality of the finite friction contact model introduced with PTC Creo Simulate 3.0. It is being compared with the friction-free and infinite friction contact model used exclusively until Creo Simulate 2.0. It is being tried to demonstrate the mode of operation of the new model with help of two examples: A brake sword clamped by two brake pads and a bolted flywheel. Because of actual software quality problems, the usability of the contact model for the user is being rated (status Creo 3.0 M080 / Creo 2.0 M200). Furthermore, comprehensive feedback is given to the software developer PTC
Gao, Nan. „Observateurs dynamiques et commande des systèmes : application aux systèmes de grande dimension“. Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0081/document.
Der volle Inhalt der QuelleThe present thesis is the result of research conducted in Longwy, within the department Control, Identification, Diagnosis (CID) of Research Center for Automatic Control of Nancy (CRAN). This thesis investigates the problem of dynamic observer (full- and reduced-order) and observer-based control design and their applications to large-scale systems. Firstly, a new form of H-infinity dynamic observer is designed for linear systems in the presence of unknown inputs and disturbances. The proposed observer generalizes the existing results on proportional observer and proportional integral observer. The observer design is based on the solution of linear matrix inequalities (LMI). Both continuous-time and discrete-time systems are considered. Thereafter, by inserting the proposed observer into a closed-loop, an observer-based control is presented for uncertain systems in the presence of disturbances. Based on the parameterization of algebraic constraints obtained from the analysis of the estimation error, the control design is derived from the solution of bilinear matrix inequality, by using a two-steps algorithm. Finally, the obtained results have been extended to large-scale systems. A decentralized observer-based control is proposed for large-scale uncertain systems in the presence of disturbances. These systems are composed of several interconnected subsystems of low dimensions, where the interconnections are assumed to be nonlinear and satisfy quadratic constraints
Bel, Haj Frej Ghazi. „Estimation et commande décentralisée pour les systèmes de grandes dimensions : application aux réseaux électriques“. Electronic Thesis or Diss., Université de Lorraine, 2017. http://www.theses.fr/2017LORR0139.
Der volle Inhalt der QuelleThis thesis focuses on the decentralized estimation and control for large scale systems. The objective is to develop software sensors that can produce a reliable estimate of the variables necessary for the interconnected nonlinear systems stability analysis. A decomposition of a such large system into a set of n interconnected subsystems is paramount for model simplification. Then, taking into account the nature of the subsystem as well as the interconnected functions, observer-based decentralized control laws have been synthesized. Each control law is associated with a subsystem which allows it to be locally stable, thus the stability of the overall system is ensured. The existence of an observer and a controller gain matrix stabilizing the system depends on the feasibility of an LMI optimization problem. The LMI formulation, based on Lyapunov approach, is elaborated by applying the DMVT technique on the nonlinear interconnection function, assumed to be bounded and uncertain. Thus, non-restrictive synthesis conditions are obtained. Observer-based decentralized control schemes have been proposed for nonlinear interconnected systems in the continuous and discrete time. Robust Hinfini decentralized controllers are provided for interconnected nonlinear systems in the presence of perturbations and parametric uncertainties. Effectiveness of the proposed schemes are verified through simulation results on a power systems with interconnected machines
Dumaz, Laure. „Processus auto-interagissants et grandes déviations“. Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00772274.
Der volle Inhalt der QuelleKassas, Zaher. „Optimal [H-2] and [H-infinity] control of extremely large segmented telescopes“. Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-08-1618.
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Sturm, Stephan [Verfasser]. „Small-time large deviations for sample paths of infinite dimensional symmetric dirichlet processes / vorgelegt von Stephan Sturm“. 2010. http://d-nb.info/1007320141/34.
Der volle Inhalt der QuelleBill, AF. „Using Fathom® statistical education software in high school to examine students' acceptance of virtual simulation and use of simulation to model sample size when sampling from large and infinite populations“. Thesis, 2012. https://eprints.utas.edu.au/15893/1/front-bill-2012.pdf.
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