Este trabalho é em parte baseado no livro The Stability and Control of Discrete Processes de Joseph P. LaSalle. Nós estudamos equações como x(n+1) = T(x(n)), onde T : \' R POT. m\' \' SETA\' \'R POT. m\' é uma aplicação contínua, com o sistema dinâmico associado \'PI\' (n,x) := \' T POT. n\' (x). Nós fornecemos condições suficientes para a estabilidade de equilíbrios usando o método direto de Liapunov. Também consideramos sistemas discretos da forma x(n+1)=T(n, x(n),\'lâmbda\' ) dependendo de uma parâmetro \' lâmbda\' e apresentamos resultados obtendo estimativas de atratores. Finalmente, nós apresentamos algumas simulações de sistemas acoplados como uma aplicação em sistemas de comunicação / This work is in part based on the book The Stability and Control of Discrete Processes of Joseph P. LaSalle. We studing equations as x(n+1) = T(x(n)), where T : \' R POT.m\' \' ARROW\' \' \' R POT.m\' is continuous transformation, with the associated dynamic system \'PI\' (n,x) := \' T POT.n\' (x). We provide suddicient conditions for stability of equilibria, using Liapunov direct method. We also consider nonautonomous discrete systems of the form x(n + 1) = T(n, x(n), \' lâmbda\') depending on the parameter \'lâmbda\' and present results obtaining uniform estimatives of attractors. We finally we present some simulations on synchronization of coupled systems as an application on communication systems

This masters thesis main focus is a statement of cash flows as regulated by czech accounting legislation, International Financial Reporting Standards and US GAAP. First chapter describes the importance of Statement of cash flows and his value added for users of financial statements. The historical context of the statement is shown, it is stated which entities are obligated to report statement of cash flows and lastly the internal structure of the statement is discussed. The second chapter begins by general methods of preparing the statement, then so called specific items are dealt with. The solution of some advanced accounting transactions (government grants, leases, loans, deferred payments etc.) is described. In the end the presentation and dislocure requirements are discussed. Last chapter contains research, where 99 companies are researched, answers are made concerning stated research questions and research hypothesis are concluded.

Ma thèse en automatique s’inscrit dans la thématique de recherche «Transport» du LAMIH. L’objectif est d’améliorer le fonctionnement des moteurs thermiques (essence), notamment en réduisant la consommation et la pollution. Face à cet enjeu écologique et économique, et compte tenu des nouvelles normes et des stratégies court-termistes de l’industrie (scandale Volkswagen...), de nouveaux contrôleurs doivent être conçus pour piloter l’arrivée d’air et d’essence au sein du moteur. En considérant l’aspect hautement non-linéaire du système, la représentation Takagi-Sugeno et le background théorique du LAMIH sont utilisés. Un premier contrôleur est synthétisé pour régler le problème de la vitesse de ralenti du moteur. Cependant, la complexité du système impose l’utilisation d’un contrôleur très coûteux d’un point de vue computationnel. Un contrôleur alternatif est donc synthétisé afin d’être implémenté dans l’ordinateur embarqué du moteur. Un second contrôleur est obtenu pour maintenir la richesse en proportions stoechiométriques afin de réduire la pollution. Ce système étant sujet à un retard de transport variable, un changement de domaine est réalisé afin de rendre ce retard constant, et de concevoir un contrôleur simple et efficace. Des essais réels sur le banc d’essai moteur du LAMIH sont réalisés afin de valider la méthodologie présentée. / My PhD in Automatic Control is part of the research theme “Transport” of the LAMIH. The objective is to improve the functioning of the gasoline engines, mainly by reducing the fuel consumption and the pollution. With this ecologic and economic challenge, and taking into account the new norms and the short-term strategies of the industry (scandal of Volkswagen...), new controllers have to be designed to control the air valve and the fuel injection inside the engine. Considering the highly nonlinear aspect of the system, the Takagi-Sugeno representation and the theoretical background of the LAMIH have been used. A first controller is designed to solve the problem of idle engine speed. However, the complexity of the system forces the use of a controller that is very costly from a computational point of view. An alternative controller is then designed in order to be implemented inside the embedded computer of the engine. A second controller is obtained to maintain the air-fuel ratio in stoichiometric proportions in order to reduce the pollution. This system being subject to a variable transport delay, a change of domain is realized to make this delay constant, and to design a simple and efficient controller. Real-time experiments have been realized on the engine test bench of the LAMIH in order to validate the presented methodology.

L’objectif principal de cette thèse consiste à étudier plusieurs thématiques : l’étude de l’observation et la commande d’un système de structure flexible et l’étude de la stabilité asymptotique d’un système d’échangeurs thermiques. Ce travail s’inscrit dans le domaine du contrôle des systèmes décrits par des équations aux dérivées partielles (EDP). On s’intéresse au système du corps-poutre en rotation dont la dynamique est physiquement non mesurable. On présente un observateur du type Luenberger de dimension infinie exponentiellement convergent afin d’estimer les variables d’état. L’observateur est valable pour une vitesse angulaire en temps variant autour d’une constante. La vitesse de convergence de l’observateur peut être accélérée en tenant compte d’une seconde étape de conception. La contribution principale de ce travail consiste à construire un simulateur fiable basé sur la méthode des éléments finis. Une étude numérique est effectuée pour le système avec la vitesse angulaire constante ou variante en fonction du temps. L’influence du choix de gain est examinée sur la vitesse de convergence de l’observateur. La robustesse de l’observateur est testée face à la mesure corrompue par du bruit. En mettant en cascade notre observateur et une loi de commande stabilisante par retour d’état, on souhaite obtenir une stabilisation globale du système. Des résultats numériques pertinents permettent de conjecturer la stabilité asymptotique du système en boucle fermée. Dans la seconde partie, l’étude est effectuée sur la stabilité exponentielle des systèmes d’échangeurs thermiques avec diffusion et sans diffusion. On établit la stabilité exponentielle du modèle avec diffusion dans un espace de Banach. Le taux de décroissance optimal du système est calculé pour le modèle avec diffusion. On prouve la stabilité exponentielle dans l’espace Lp pour le modèle sans diffusion. Le taux de décroissance n’est pas encore explicité dans ce dernier cas. / The main objective of this thesis consists to investigate the following themes : observation and control of a flexible structure system and asymptotic stability of a heat exchangers system. This work is placed in the field of the control of systems described by partial differential equations (PDEs). We consider a rotating body-beam system whose dynamics are not physically measurable. An infinite-dimensional exponentially convergent Luenberger-like observer is presented in order to estimate the state variables. The observer is also valid for a time-varying angular velocity around some constant. We can accelerate the decay rate of the observer by a second step design. The main contribution of this work consists in building a numerical simulator based on the finite element method (FEM). A numerical investigation is carried out for the system with constant or time-varying angular velocity. We examine the influence of the gain choice on the decay rate of the observer. The robustness of the observer is tested with the measurement corrupted by noise. By cascading our observer and a feedback control law, we wish to obtain a global stabilization of the rotating bodybeam system. The relevant numerical results make it possible for us to conjecture that the closed-loop system is locally asymptotically stable. We investigate the exponential stability of the heat exchangers systems with diffusion or without diffusion. We establish the exponential stability of the model with diffusion in a Banach space. Moreover, the optimal decay rate of the system is computed for the model with diffusion. We prove exponential stability in (C[0, 1])4 space for the model without diffusion. The optimal decay rate in the latter case is not yet found.

This diploma thesis describes a JSD600 unit intended for mathematical processing, measuring and data recording. The JSD600 unit is highly intended for industrial measuring of water steam energy delivery.First part of the work focuses on basics of the JSD600 unit detailing and describing main structures and principles for relevant data storing.Next part summarizes some basic facts and knowledge from the area of industrial liquid flow, energy measuring and describes water steam states. All these points within this range are needed for dilemma understanding.Last task deals with complete list of communication datagrams, which have been used for communication with JSD600 unit, including a main packet of structure descriptions.The second part of this dissertation brings the unit setup application description including some implementation details of the most interesting parts.