Dissertations / Theses on the topic 'Contrôle relaxé'
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Mezerdi, Mohamed Amine. "Equations différentielles stochastiques de type McKean-Vlasov et leur contrôle optimal." Electronic Thesis or Diss., Toulon, 2020. http://www.theses.fr/2020TOUL0014.
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Nous considérons les équations différentielles stochastiques (EDS) de Mc Kean-Vlasov, qui sont des EDS dont les coefficients de dérive et de diffusion dépendent non seulement de l'état du processus inconnu, mais également de sa loi de probabilité. Ces EDS, également appelées EDS à champ moyen, ont d'abord été étudiées en physique statistique et représentent en quelque sorte le comportement moyen d'un nombre infini de particules. Récemment, ce type d'équations a suscité un regain d'intérêt dans le contexte de la théorie des jeux à champ moyen. Cette théorie a été inventée par P.L. Lions et J.M. Lasry en 2006, pour résoudre le problème de l'existence d'un équilibre de Nash approximatif pour les jeux différentiels, avec un grand nombre de joueurs. Ces équations ont trouvé des applications dans divers domaines tels que la théorie des jeux, la finance mathématique, les réseaux de communication et la gestion des ressources pétrolières. Dans cette thèse, nous avons étudié les questions de stabilité par rapport aux données initiales, aux coefficients et aux processus directeurs des équations de McKean-Vlasov. Les propriétés génériques de ce type d'équations stochastiques, telles que l'existence et l'unicité, la stabilité par rapport aux paramètres, ont été examinées. En théorie du contrôle, notre attention s'est portée sur l'existence et l'approximation de contrôles relaxés pour les systèmes gouvernés par des EDS de Mc Kean-VlasovWe consider Mc Kean-Vlasov stochastic differential equations (SDEs), which are SDEs where the drift and diffusion coefficients depend not only on the state of the unknown process but also on its probability distribution. These SDEs called also mean- field SDEs were first studied in statistical physics and represent in some sense the average behavior of an infinite number of particles. Recently there has been a renewed interest for this kind of equations in the context of mean-field game theory. Since the pioneering papers by P.L. Lions and J.M. Lasry, mean-field games and mean-field control theory has raised a lot of interest, motivated by applications to various fields such as game theory, mathematical finance, communications networks and management of oil resources. In this thesis, we studied questions of stability with respect to initial data, coefficients and driving processes of Mc Kean-Vlasov equations. Generic properties for this type of SDEs, such as existence and uniqueness, stability with respect to parameters, have been investigated. In control theory, our attention were focused on existence, approximation of relaxed controls for controlled Mc Kean-Vlasov SDEs
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Fernandes, João Luís Gameiro. "Efeitos do suster-relaxar na cinemática tridimensional, função neuromuscular e sintomatologia álgica de um atleta de crossfit com dor lombar: um estudo de caso." Bachelor's thesis, [s.n.], 2016. http://hdl.handle.net/10284/5730.
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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em FisioterapiaIntrodução: A lombalgia está associada a alterações da atividade muscular e da cinemática lombo-pélvica provocada, em parte, pela fraqueza da musculatura do core. O teste de Thomas é utilizado nas áreas clínica e desportiva para determinar o encurtamento do ilíopsoas e do reto femoral, músculos constituintes do core. O encurtamento destes músculos é um dos fatores de risco de lesão músculo-esquelética nos membros inferiores e de dor lombar. A técnica de suster-relaxar, aumenta a amplitude de movimento articular, normalizando o tónus muscular. Objetivo: Avaliar o efeito da técnica de suster-relaxar na cinemática tridimensional do teste de Thomas, na função neuromuscular e sintomatologia álgica de um atleta de crossfit com dor lombar à direita. Metodologia: Análise da cinemática tridimensional do teste de Thomas através do sistema de captura e análise de movimento 3D, Qualisys Oqus Camera Series, e força isocinética dos joelhos pela dinamometria isocinética, antes e após a aplicação técnica suster-relaxar num atleta de crossfit de 25 anos. Resultados: Após a análise dos dados obtidos, verificou-se um aumento da amplitude de extensão da anca, do peak torque e diminuição da sintomatologia álgica, no lado afetado do atleta, em resultado da aplicação da técnica de suster-relaxar. Conclusão: A técnica suster-relaxar aumenta a amplitude de movimento articular, e o peak torque e diminui a sintomatologia de dor lombar associado a uma disfunção sacroilíaca num atleta de crossfit.
Introduction: Low back pain is associated with changes in muscle activity and lumbar- pelvic kinematics caused, partly by the weakness of the core musculature. The Thomas test is widely used in clinical and sports areas to determine the shortening of the iliopsoas and rectus femoris, core constituent muscles. The shortening of these muscles is one of the risk factors for musculoskeletal injury in the lower limbs and back pain. The technique of hold-relax, increases range of motion, normalizing muscle tone. Objective: To access the effect of the hold-relax technique in the three-dimensional kinematics of the Thomas test, neuromuscular function and symptoms of a crossfit athlete with right low back pain. Methodology: Analysis of three-dimensional kinematics of the Thomas test through the capture system and 3D motion analysis, Qualisys Oqus Camera Series, and isokinetic strength of the knee by isokinetic dynamometer before and after the hold-relax technique application in a 25 years crossfit athlete. Results: After analysing the data, there was an increase in hip extension range, peak torque and reduction of pain symptoms on the affected side of the athlete, as a result of the technical application of hold-relax. Conclusion: The hold-relax technique increases range of motion andpeak torque and decreases lumbar pain symptoms associated with a sacroiliac dysfunction in a crossfit athlete.
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Ivarsson, Mikael. "Modular relay control." Thesis, Mälardalen University, School of Innovation, Design and Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-10369.
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Enics Sweden AB, Västerås, is an electronics manufacturing services company with its main business in manufacturing electronics. Most, if not all, electronic devices that are manufactured are being widely tested before delivery to ensure proper functionality. Often during tests a large number of signals are measured by one to a few digital multimeters and are therefore controlled through relays. Relays are also used when applying stimuli with high currents or voltages to the unit under test.
This work have been focused on finding a concept, including designing and producing a prototype, for a modular relay control system for use in fabrication of small test systems and for use when there is a need for adding more relays to an existing system.
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Hunt, Richard K. "Hidden Failure in Protective Relays: Supervision and Control." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36571.
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This thesis performs simulations of a relay supervisory system (RSS) that works passively in conjunction with the existing protective relaying system at a substation. During normal system operating conditions, the RSS supervises the relay system to prevent trips due to hidden failures. During wide area network disturbances, it adapts the relay system to increase security of the power system. The RSS works passively in the sense that it waits for events to occur in the existing relay system before taking any action.
The simulation performed includes a model of the RSS, along with simplified models of existing relays, performed in Matlab. A power system model in EMTP provides inputs to the RSS model. Multiple faults are applied to the EMTP model, and the RSS is tested under each fault condition, and with a variety of relay hidden failures. For all tests performed, the simulation of the RSS successfully prevents relay hidden failure from removing circuit elements inadvertently, while allowing correct relay operations to remove circuit elements.Master of Science
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Majhi, Somanath. "Relay feedback process identification and controller design." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297557.
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The aim of this thesis is to investigate relay feedback process identification and some controller design methods. Using an exact analysis method, namely the state space method, a set of conditions for the prediction of oscillations in relay control systems has been developed. Since the exact solution for the limit cycle is found it becomes possible to assess the stability of these oscillations using an eigenvalue criterion. A correction factor has been introduced to overcome the limitations of the Balasubramanian's eigenvalue criterion. Relay feedback identification in process control can lead to erroneous results if the system parameters are estimated from the approximate describing function approach. Exact analytical expressions are derived and on the basis of these expressions an identification procedure is suggested which is capable of estimating the parameters of a class of process transfer functions. Analytical expressions are presented for quantifying the approximate estimation errors in the presence of measurement noise and load disturbance. The performance limitations of the conventional PID controller have been clearly shown in the context of controlling resonant, unstable or integrating processes. It has been shown that a PI-PD controller with the PD in the inner loop not only avoids the derivative kick but also a better performance is achieved than with a P or D controller in the inner loop. Further, the same controller provides good disturbance rejection and its performance is often near to that of an optimum controller for disturbance rejection and is significantly better than the results of other design methods based on setpoint response. Simple tuning methods based on standard forms for a PI-PD controller controlling time delay processes have been presented which are particularly effective for integrating and unstable plants. Automatic tuning formulae for PI, PID and PI-PD controllers have been proposed for controlling stable and unstable processes. The problem of controlling integrating and unstable processes incorporating time delay has been tackled by proposing a new Smith predictor. It is shown that the predictor is capable of successfully controlling stable, integrating and unstable processes. Controller parameters leading to robust performance for various levels of uncertainty in the model parameters particularly in the unstable time constant and time delay have been presented. Also, simple and effective automatic tuning formulae are derived for the new Smith predictor structure when the plant model is not available assuming first order model with time delay for stable, unstable and integrating processes. The plant model blocks in the control structure, as well as all the controllers, are designed from a single symmetrical relay test.
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Ferssiwi, Abdesslam. "Contrôle hypothalamique des processus de renforcement dans un relais gustatif : l'aire branchiale." Bordeaux 1, 1987. http://www.theses.fr/1987BOR10545.
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Hunt, Gregory William. "Transportation relay network design." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/25788.
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Jiang, Peng. "Cooperative control of relay based cellular networks." Thesis, Queen Mary, University of London, 2009. http://qmro.qmul.ac.uk/xmlui/handle/123456789/577.
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The increasing popularity of wireless communications and the higher data requirements of new types of service lead to higher demands on wireless networks. Relay based cellular networks have been seen as an effective way to meet users’ increased data rate requirements while still retaining the benefits of a cellular structure. However, maximizing the probability of providing service and spectrum efficiency are still major challenges for network operators and engineers because of the heterogeneous traffic demands, hard-to-predict user movements and complex traffic models. In a mobile network, load balancing is recognised as an efficient way to increase the utilization of limited frequency spectrum at reasonable costs. Cooperative control based on geographic load balancing is employed to provide flexibility for relay based cellular networks and to respond to changes in the environment. According to the potential capability of existing antenna systems, adaptive radio frequency domain control in the physical layer is explored to provide coverage at the right place at the right time. This thesis proposes several effective and efficient approaches to improve spectrum efficiency using network wide optimization to coordinate the coverage offered by different network components according to the antenna models and relay station capability. The approaches include tilting of antenna sectors, changing the power of omni-directional antennas, and changing the assignment of relay stations to different base stations. Experiments show that the proposed approaches offer significant improvements and robustness in heterogeneous traffic scenarios and when the propagation environment changes. The issue of predicting the consequence of cooperative decisions regarding antenna configurations when applied in a realistic environment is described, and a coverage prediction model is proposed. The consequences of applying changes to the antenna configuration on handovers are analysed in detail. The performance evaluations are based on a system level simulator in the context of Mobile WiMAX technology, but the concepts apply more generally.
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Desnoyers, Peter J. (Peter Joseph). "Congestion control in large frame relay networks." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14747.
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Brahmia, Mohamed El Amine. "Mécanismes de contrôle de la qualité de services dans les réseaux WiMAX relais." Thesis, Mulhouse, 2012. http://www.theses.fr/2012MULH4074.
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Nous assistons ces dernières années à une émergence constante de nouvelles applications, notamment pour les services audiovisuels. Ces applications imposent au réseau un certain nombre de contraintes pour qu’elles puissent fonctionner correctement. Le développement de mécanismes permettant d’offrir une garantie à ces contraintes, est donc devenu un objectif crucial. La norme IEEE 802.16j est l’une des solutions sans fil qui propose plus de ressources afin de supporter les nouveaux services de télécommunications. Dans la présente thèse, nous focalisons notre étude sur la problématique de la qualité de service dans les réseaux WiMAX relais. Nos contributions se regroupent à travers les étapes ci-dessous : Nous proposons un protocole de routage multicast pour les services IPTV (HDTV, SD-TV, Web-TV et Mobile-TV). Ce protocole repose d’une part sur un nouveau mécanisme de construction de l’arbre multicast basé sur les nombres premiers et d’autre part, sur une nouvelle méthode d’agrégation basée sur le standard de compression Vidéo «SVC». L’objectif est de supporter l’hétérogénéité des utilisateurs tout en optimisant la consommation des ressources. Par ailleurs, nous étudions le problème d’ordonnancement dans les réseaux WiMAX. Nous proposons un algorithme d’ordonnancement adaptatif AWRR, ce dernier se base sur une technique à charge pondérée. L’objectif est d’ajuster dynamiquement le poids de chaque classe de service, en prenant en compte la charge de la file d’attente et les contraintes de la QoS. Enfin, nous nous intéressons à l’étude de la problématique du chemin optimal contraint. Nous proposons une solution déterministe basée sur une fonction de coût. Notre fonction permet aussi d’assurer le contrôle d’admission, elle se base sur deux fonctions de coût élémentaires qui prennent en compte quatre critères de QoSOver recent years, new applications steadily developed in a tremendous space, especially in audiovisual services area. The present applications have some of constraints to work properly. The developments of mechanism which enable to overcome these constraints become a critical issue in this area. The IEEE 802.16j standard is one of wireless communication technology which offering more resources to support new telecommunication services. In this thesis, we focus our research on the problem of quality of service (QoS) inWiMAX relay networks. Our contributions are classified as follows : we proposed a multicast routing protocol for IPTV services (such as HD-TV, SD-TV, Web-TV and Mobile-TV). This proposed protocol used a new multicast tree construction mechanism based-on prime numbers. We also developed a new aggregation method based on standard video compression called Scalable Video Coding (SVC). Our goal is to support user’s heterogeneity while optimizing resources consumption. In addition, we studied the problem of scheduling inWiMAX networks.We proposed an adaptive scheduling algorithm AWRR for IPTV services. The aim of this method is to support QoS constraints by using two schedulers, and assigning a dynamic value to each service queue. Finally, we interested to study about the problem of path selection. We proposed a solution based on a deterministic cost function. This function also ensures admission control based on two basic cost functions which include four QoS criteria. This thesis has been prepared in the MIPS/GRTC laboratory, University of Haute Alsace, under a research contract external (CRE) framework with France Telecom R&D. All proposed mechanisms were evaluated by the simulator QualNet, Matlab and mathematical analysis
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Zhao, Yanbin. "Relaxed stability analysis of fuzzy-model-based control systems." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/relaxed-stability-analysis-of-fuzzymodelbased-control-systems(df7ec615-6b23-4344-844d-00300a43f975).html.
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This thesis presents and extrapolates on the research works concerning the stability analysis of fuzzy-model-based (FMB) control systems. In this study, two types of FMB control systems are considered: 1) Takagi-Sugeno (T-S) FMB control systems; and 2) polynomial fuzzy-model-based (PFMB) control systems. The control scheme illustrated in this thesis has great design flexibility because it allows the number and/or shape of membership functions of fuzzy controllers to be designed independently from the fuzzy models. However, in wake of the imperfectly matched membership functions, the stability conditions of the FMB control systems are typically very conservative given the fact that they are con-gruent with traditional stability analysis methods. In this thesis, based on Lya-punov stability theory, membership-function-dependent (MFD) stability analysis methods are proposed to relax the stability conditions. Firstly, piecewise mem-bership functions (PMFs) are utilised as approximate membership functions to carry out a relaxed stability analysis of T-S FMB control system. Subsequently, PMF-based stability analysis is improved with the consideration of membership function boundary information. Based on the PMF method, we propose a lower-upper-PFM-based stability analysis method. Relaxed stability conditions are obtained in the form of linear matrix inequalities (LMIs) in consideration of the approximation accuracy of the membership function. For the purpose of stability analysis of PFMB control system, the other MFD method proposed is to extract the regional membership function information via operating domain partition. Two types of membership information are consid-ered in each sub-domain: 1) the numerical relationship between all membership function overlap terms; and 2) the bounds of every single membership function overlap term. Thereafter, relaxed sum of squares (SOS)-based stability conditions are derived. In conjunction with these proposed MFD methods, sub-domain fuzzy controllers are utilised to enhance the capability of feedback compensation. In this thesis, all the LMI/SOS-based stability conditions obtained can be solved nu-merically using existing computational tools. Furthermore, simulation examples are provided to illustrate the validity and applicability of the proposed methods.
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Guerreiro, covita João. "Role of relaxin-3/RXFP3 forebrain networks in the descending control of pain in the mouse." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0121.
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La douleur est un processus biologique complexe qui alerte sur les changements potentiellement délétères de l’environnement et s’avère nécessaire à la survie de l’organisme. Toutefois, l’activation continue de ce système de signalisation peut provoquer des changements maladaptifs qui se caractérisent par des altérations anatomiques et fonctionnelles. La douleur est considérée comme chronique lorsque sa durée dépasse 3 mois. Les douleurs chroniques sont accompagnées de problèmes économiques et sociaux qui font de leur traitement une priorité de santé publique.Le cerveau décode les composantes sensori-discriminatives et affectives de la douleur. Il détermine ainsi le type de douleur (pincement, brûlure, etc.), et sa localisation dans l’organisme, et sa valeur aversive, respectivement. Le cerveau transmet ensuite à la périphérie des informations en accord avec les stimuli reçus, et qui tiennent aussi compte des expériences présentes et passées de l’individu.Le signal nociceptif est modulé à toutes les étapes de sa transmission par la mise en jeu de nombreux systèmes neurochimiques, et en particulier par des neuropeptides. La présence de neuropeptides et de leurs récepteurs dans des aires du système nerveux central (SNC) impliquées dans la transmission douloureuse suggère que les systèmes peptidergiques participent au contrôle de la nociception.La relaxine-3 est un neuropeptide principalement synthétisée dans une région du rhombencéphale appelée Nucleus Incertus (NI). Depuis sa découverte, la relaxine-3 a été impliquée, via l’activation de son récepteur RXFP3, dans le contrôle d’une large variété de comportements tels que l’anxiété, l’éveil, la recherche de récompense. Ces rôles de la signalisation relaxine-3/RXFP3 suggèrent que l’activation du récepteur RXFP3 pourrait contribuer à la modulation de la sensibilité douloureuse.Mes travaux visaient initialement à évaluer les effets de l’activation et de l’inhibition du récepteur RXFP3 sur la sensibilité thermique et mécanique dans des conditions normales et en situation de douleurs persistantes. Nos travaux ont démontré que l’administration centrale, par injection intracérébroventriculaire (icv), de l’agoniste peptidique A2 du récepteur RXFP3, provoquaient une diminution de la sensibilité mécanique mais pas thermique. De plus, l’injection icv de l’antagoniste peptidique R3(B1-22)R augmente la sensibilité mécanique et thermique. Ces données suggèrent que la signalisation relaxine-3/RXFP3 exerce un effet tonique inhibiteur sur la sensibilisation mécanique et thermique, et que la mise en jeu du récepteur RXFP3 pourrait avoir des propriétés antalgiques.De plus, j’ai étudié la mise en jeu de différentes aires cérébrales en comparant l’immunoréactivité c-Fos dans différentes régions après injection de l’agoniste A2. Toutefois, ces travaux n’ont pas révélé de différence dans le nombre des cellules marquées ni dans l’intensité du marquage.L’hybridation in situ de différentes aires cérébrales a permis d’identifier les populations exprimant les ARNm de RXFP3. J’ai analysé la coexpression des ARNm de marqueurs spécifiques, parvalbumine et somatostatine, et déterminé l’expression relative des ARNm de RXFP3 parmi ces populations.Enfin, j’ai examiné une possible anxiété comorbide chez des souris en conditions de douleur inflammatoire. De manière surprenante, le comportement anxieux n’était pas modifié chez ces souris suggérant que ce modèle ne développe pas d’anxiété et que l’activation du RXFP3 cible spécifiquement la transmission nociceptive.L’ensemble de mes résultats montre l’implication du système relaxine-3/RXFP3 dans le contrôle de la douleur, offrant de nouvelles possibilités pour le développement d’outils thérapeutiques en ciblant un système peptidergique susceptible d’impacter plusieurs comportements altérés en conditions de douleurs chroniquesPain is a complex biological phenomenon that is beneficial and necessary for our survival, warning of changes and hazards in the environment that compromise optimal function. However, continuous activation of pain signalling systems results in maladaptive changes characterized by altered tissue and organ structure and activity. Pain lasting more than 3 months is termed chronic pain and it is under these conditions that it becomes a major burden for affected individuals. Chronic pain is also accompanied by serious social and economic burdens, making research in this field a high priority globally.The central nervous system (CNS) acts as a major control centre for nociceptive signal transmission, decoding pain for its sensory-discriminative and aversive components, i.e., deciphering the type of pain (pinch, burn, etc.), its location in the body, and its associated hedonic value, respectively. Once the information is decrypted, neural signals from the brain to the periphery act in accordance with the provided stimulus based on past and current experiences.The nociceptive signal is modulated at every step of this process by an abundance of neurochemical signals, including neuropeptides. The presence of neuropeptides and/or their receptors in areas linked to nociceptive processing and transmission suggests putative roles for these systems in the control of nociception.Relaxin-3 is a neuropeptide that is mainly synthesized in a hindbrain region known as the nucleus incertus (NI). Since its discovery, relaxin-3 has been linked to the control of a wide range of behaviours such as anxiety-like behaviours, arousal, and reward-seeking, through activation of the Gi/o-protein-coupled receptor, RXFP3. These putative roles of relaxin-3/RXFP3 signalling suggest a possible link between RXFP3 activation and modulation of pain sensitivity.Therefore, my initial studies assessed the effect of RXFP3 activation and inhibition on mechanical and thermal pain sensitivity in normal and persistent pain conditions. These studies demonstrated that central administration of the RXFP3 agonist peptide, RXFP3-A2, via intracerebroventricular (icv) injection, produced relief of mechanical, but not thermal, pain sensation. Moreover, icv injection of the RXFP3 antagonist peptide, R3(B1-22)R, augmented mechanical and thermal pain sensitivity. These data suggest that relaxin-3/RXFP3 signalling has a tonic action in maintaining mechanical and thermal pain thresholds, and the potential for activation of RXFP3 to produce pain relief.Additionally, I examined the possible involvement of different brain areas in these effects, by assessing the number of c-Fos-positive cell nuclei under different conditions. However, these studies revealed no difference in the number of c-Fos-positive cell nuclei or staining intensity in the vehicle- and RXFP3 agonist-treated mice.Further characterization of pain circuit-related brain areas using multiplex in situ hybridization revealed that RXFP3 mRNA is expressed within discrete populations of neurons in these areas. I also evaluated possible co-expression of RXFP3 mRNA with somatostatin and parvalbumin mRNA, and determined the relative proportion of RXFP3 mRNA expression in populations of neurons that express these transcripts.Finally, I examined the possible presence of comorbid anxiety in mice subjected to the persistent pain protocol. However, anxiety-like behaviour was not altered in mice with persistent hindpaw pain, suggesting this model does not display produce anxiety, and that effects of RXFP3 modulation observed specifically targeted nociceptive transmission.Overall, my findings implicate the relaxin-3/RXFP3 system in control of pain transmission, providing new opportunities for the development of therapeutic tools for pain management, by targeting a neuropeptide system that impacts several behaviours that are altered in chronic pain conditions
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Vaidyanathan, Sundararaman. "A feasibility study of an adaptive reclosing relay." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/44091.
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Logic for an adaptive reclosing relay has been developed.
The relay works correctly in a wide number of fault cases. The
relay has the following distinguishing characteristics :
(a) Reclosing into a three phase fault is avoided under all
circumstances.
(b) The logic is applicable only for circuit breakers which. have
reclosing on individual phases.
(c) The relay works correctly in the case of both (shunt)
compensated and uncompensated lines.Master of Science
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Feng, Jiao. "Distributed relay selection aided cooperative medium access control." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/362096/.
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A variety of cooperative medium access control (MAC) schemes are designed for the sake of improving the achievable transmit rate and for reducing the transmit energy dissipation of cooperative communication systems relying on realistic greedy - rather than altruistic - relay nodes (RNs). Based on the system’s objective functions (OF), novel distributed relay selection schemes are developed for selecting the best relay node (RN) set. In order to investigate the effect of the proposed MAC schemes on the performance of the cooperative communication systems considered, the system’s stability is analysed with the aid of queueing theory. Specifically, we first consider a cooperative spectrum leasing system (CSLS) supporting a licensed source node (SN) and a licensed destination node (DN) as well as multiple unlicensed greedy RNs, which require rewards for providing cooperative transmission assistance. A ’win-win’ (WW) cooperative framework (WWCF) is formulated for sake of improving the achievable transmit rate and for simulanteously minimizing the energy dissipation of the co- operative spectrum leasing system considered. Based on the proposed WWCF, the licensed SN intends to lease part of its spectrum to the unlicensed RNs in exchange for cooperative support, leading to an improved transmit rate, while simultaneously reducing the transmit power. The unlicensed RNs also have an incentive to provide cooperative transmission assistance for the SN, since in exchange for relaying assistance they are allowed to access the licensed spectrum for transmitting their own data, and even to maintain their own target Quality of Service (QoS). Furthermore, a distributed WW cooperative MAC protocol is developed for implementing the proposed WWCF by designing a specific signalling procedure and the format of both the data frame control messages as well as a distributed relay selection scheme. More explicitly, a novel backoff algorithm is designed for distributively selecting the best RN in order to optimize the system’s OF formulated by our WWCF. Our simulation results demonstrated that both substantial rate improvements and considerable energy savings are achieved by implementing the proposed distributed WW cooperative MAC protocol. However, encountering a low service rate at the MAC layer may excessively increase the length of queue in the buffer storing the incoming packet. Hence, the queueing system may become unstable due to the low service rate limited by an inferior MAC protocol design. Hence we conceived a queueing model for our cooperative spectrum leasing system relying on the proposed distributed WW cooperative MAC protocol. In order to simplify the stability analysis, some idealized simplifying assumptions are invoked and a non-Markovian analysis method is used for investigating the transmission probability of each node and for deriving the average departure rates at both the SN and the RNs operating under the control of the proposed distributed WW cooperative MAC protocol. Our simulation results confirmed that an increased stable throughput is provided by the proposed distributed WW cooperative MAC protocol for both the SN and RNs compared to the benchmark schemes. As an improved extension of the proposed WWCF, a WW reciprocal-selection-based framework (WWRSF) is formulated for a cooperative spectrum leasing system hosting multiple licensed transmission pairs and multiple unlicensed transmission pairs. The SN of a licensed pair of nodes is referred as the primary transmitter (PT), while the SN of an unlicensed transmission pair is termed as the secondary transmitter (ST). Based on the proposed WWRSF, the PT intends to lease its spectral resources to an appropriate secondary transmitter (ST) in exchange for cooperative transmission assistance for the sake of minimizing its transmit power and simultaneously satisfying its transmit rate requirement. The ST has an incentive to collaborate with the best PT for the sake of minimizing the ST’s transmit power under the constraint of its QoS requirement, whilst simultaneously winning a transmission opportunity for its own traffic. Based on the OFs of the proposed WWRSF, a distributed WW reciprocal-selection-based medium access scheme (DWWRS-MAS) is designed, which is capable of producing the best cooperative pairs set for the sake of reducing the transmit power of both the PT and of the ST in each cooperative pair, whilst simultaneously satisfying their transmit rate requirements. This is achieved with the aid of the proposed distributed reciprocal selection between the active PTs and STs, which have the capability of providing successful cooperative transmission assistance. Moreover, we analyse both the queueing stability and the algorithmic stability of our cooperative spectrum leasing system exploiting our DWWRS-MAS. In comparison to the benchmark schemes considered in the literature, the proposed DWWRS-MAS is capable of achieving a performance, which is comparable to that of the optimal schemes in terms of the system’s transmit power and system’s achievable transmit rate.
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Ariño, Latorre Carlos Vicente. "Relaxed LMI conditions for control of nonlinear Takagi-Sugeno models." Doctoral thesis, Universitat Politècnica de València, 2010. http://hdl.handle.net/10251/8301.
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Los problemas de optimización de desigualdades matriciales lineales en control borroso se han convertido en la herramienta más utilizada en dicha área desde los años 90. Muchos sistemas no lineales pueden ser modelados como
sistemas borrosos de modo que el control borroso puede considerarse como una técnica de control no lineal. Aunque se han obtenido muchos y buenos resultados, quedan algunas fuentes de conservadurismo cuando se comparan con
otros enfoques de control no lineal. Esta tesis discute dichas cuestiones de conservadurismo y plantea nuevos enfoques para resolverlas.
La principal ventaja de la formulación mediante desigualdades matriciales lineales es la posibilidad de asegurar estabilidad y prestaciones de un sistema no lineal modelado como un sistema borroso Takagi-Sugeno. Estos
modelos están formados por un conjunto de modelos lineales eligiendo el sistema a aplicar mediante el uso de unas reglas borrosas. Estas reglas se traducen en funciones de interpolación o de pertenecía que nos indican el
grado de validez de un modelo lineal respecto del resto. El mayor problema que presentan estas técnicas basadas en desigualdades matriciales lineales es que las funciones de pertenencia no están incluidas en las condiciones de
estabilidad del sistema, lo que significa que se prueba la estabilidad y prestaciones para cualquier forma de interpolación entre los diferentes modelos lineales. Esto genera una fuente de conservadurismo que sería conveniente limitar.
En la tesis doctoral se presentan varias metodologías capaces de trasladar la información de las funciones de pertenencia del sistema al problema basado en desigualdades matriciales lineales de estabilidad y prestaciones. Las dos principales aportaciones propuestas se basan, respectivamente, en introducir una serie de matrices de relajación que permitan incorporar esta información y en aprovechar la descripción de una amplia clase de sistemas borrosos en
productos tensoriales de...Ariño Latorre, CV. (2008). Relaxed LMI conditions for control of nonlinear Takagi-Sugeno models [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8301
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Liu, Chuang. "Relaxed stability analysis for fuzzy-model-based observer-control systems." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/relaxed-stability-analysis-for-fuzzymodelbased-observercontrol-systems(082673fa-9a83-4cda-8622-9358ed8d7118).html.
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Fuzzy-model-based (FMB) control scheme is an efficient approach to conduct stability analysis for nonlinear systems. Both Takagi-Sugeno (T-S) FMB and polynomial fuzzy-model-based (PFMB) control systems have been widely investigated. In this thesis, the stability analysis of FMB control systems is conducted via Lyapunov stability theory. The main contribution of the thesis is improving the applicability of T-S FMB and PFMB control strategies by relaxing stability conditions and designing fuzzy observer-controller, which is presented in the following three parts: 1) The stability conditions of FMB control systems are relaxed such that the FMB control strategy can be applied to a wider range of nonlinear systems. For T-S FMB control systems, higher order derivatives of Lyapunov function (HODLF) are employed, which generalizes the commonly used first order derivative. For PFMB control systems, Taylor series membership functions (TSMF) are brought into stability conditions such that the relation between membership grades and system states is expressed. 2) Two types of T-S fuzzy observer-controller are designed such that the T-S FMB control strategy can be applied to systems with unmeasurable states. For the first type, the T-S fuzzy observer with unmeasurable premise variables is designed to estimate the system states and then the estimated states are employed for state-feedback control of nonlinear systems. Convex stability conditions are obtained through matrix decoupling technique. For the second type, the T-S fuzzy functional observer is designed to directly estimate the control input instead of the system states, which can reduce the order of the observer. A new form of fuzzy functional observer is proposed to facilitate the stability analysis such that the observer gains can be numerically obtained and the stability can be guaranteed simultaneously. 3) The polynomial fuzzy observer-controller with unmeasurable premise variables is designed for systems with unmeasurable states. Although the consideration of the polynomial fuzzy model and unmeasurable premise variables enhances the applicability of the FMB control strategy, it leads to non-convex stability conditions. Therefore, two methods are applied to derive convex stability conditions: refined completing square approach and matrix decoupling technique. Additionally, the designed polynomial fuzzy observer-controller is extended for systems where only sampled-output measurements are available. Furthermore, the membership functions of the designed polynomial observer-controller are optimized by the improved gradient descent method. Simulation examples are provided to demonstrate and verify the theoretical analysis.
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Sjöberg-Linna, Annica. "Krav och Kontroll på arbetet : - vilka förklaringsvariabler påverkar individens upplevelse?" Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-14152.
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Arbetsmiljön kan enligt Karasek och Theorell (1990) karaktäriseras i två dimensioner, psykologiska krav från arbetet och i vilken utsträckning individen möter dessa med hjälp av egenkontrollen. De har utvecklat krav-kontroll modellen som mäter den psykosociala arbetsmiljön. Modellen används i denna studie för att undersöka huruvida några förklaringsvariabler relaterar till individens upplevelse av krav och kontroll på arbetet. Deltagarna fick besvara en enkät besående av olika variabler och självskattningsskalor som mätte krav och kontroll. Även känslan av sammanhang mättes med 13 frågor (Antonovsky, 1993). Deltagarna bestod av 116 anställda på två arbetsplatser i Västmanlands län. Resultatet visade att vissa dimensioner av förklaringsvariablerna (demografiska, arbets-, hälso och KASAM) bidrog till viss förklarad varians med avseende på krav och kontroll. Den psykiska hälsan hade ett positivt samband med kontroll och negativt samband med krav. Enligt Theorell (2003) mår individer med hög kontroll vanligtvis bättre än individer som uppleverlåg kontroll.
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Felício, Ana Carolina Guerios. "Correspondência entre o fazer e o dizer de psicólogos clínicos: exame do efeito de algumas variáveis antecedentes estímulos verbais para o próprio relato sobre o relato de comportamentos passados." Pontifícia Universidade Católica de São Paulo, 2011. https://tede2.pucsp.br/handle/handle/16622.
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The correspondence between what a person does and his report about his past behavior has been often studied under conditions designed, although studies under natural conditions have been less frequent. This study purposed to investigate the effects of some verbal stimuli questions, audio recording and script about past behaviors emitted by the therapist in a therapeutic session under the therapist s report about her behaviors in session. The study involved two newly graduated therapists who were studying in a postgraduate curse (behavioral therapy). Each one carried out seven therapeutic sessions with their patients and seven meetings with the researcher to answer questions about the sessions. During the meeting the therapist should write what she made after a patient s behavior that was presented in the questionnaire, where was presented the context in which the patient spoke, the therapist s verbalization and a question about the therapist s behavior. On Base Line (LB) there wasn t tips to participant s report. In phases A and B, the report was emitted after the participant listened to an audio recording (Phase A) and after she read a script followed by audio recording. The reports were analyzed based on the categories proposed by Ricci (2003). The antecedent conditions under which the reports are evoked were considered, and the correspondence in this case was less than in the situation in that the antecedent conditions were disregarded. Although there was not consistent increase in reports with the use of tips, it is possible that the therapists began to report better their behaviors, even if they did not know the patient s behavior that evoked their response during the therapeutic session
A correspondência entre o que uma pessoa faz e o seu relato sobre seu comportamento passado tem sido frequentemente estudado em condições planejadas, mas estudos em situação natural têm sido menos frequentes. O presente trabalho teve como objetivo investigar os efeitos de estímulos verbais perguntas, gravação em áudio e roteiro referentes a comportamentos passados emitidos pelo terapeuta em sessão de psicoterapia sobre o relato, por terapeutas, de seus comportamentos durante as sessões. Participaram do estudo duas terapeutas recém-formadas que faziam um curso de especialização em clínica (terapia comportamental). Cada uma delas realizou sete atendimentos com suas respectivas clientes e sete encontros com a pesquisadora para aplicação de um questionário, no qual eram apresentados episódios ocorridos durante o atendimento e solicitava-se que a participante descrevesse o que havia feito após uma dada verbalização da cliente. Cada episódio continha o contexto em que se deu a verbalização da cliente, a própria verbalização e a pergunta sobre o comportamento da terapeuta. Na fase de Linha de Base (LB), não havia nenhuma dica para o relato da participante. Nas fases A e B, o relato era emitido após a exposição da participante à gravação em áudio da sessão (Fase A) e após a leitura de um roteiro seguido da gravação (Fase B). Os relatos foram analisados com base nas categorias propostas por Ricci (2003), levando-se em consideração as condições antecedentes nas quais eles foram produzidos. Nessa análise, a correspondência entre o relato e o comportamento das participantes durante o atendimento foi menor do que quando as condições antecedentes eram desconsideradas. Embora não tenha havido uma melhora consistente nos relatos conforme as dicas para sua emissão aumentassem, é possível afirmar que as participantes passaram a relatar mais precisamente seus comportamentos, embora não tenham ficado sob controle de qual comportamento da cliente evocou determinada resposta sua na sessão
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Alkhoury, Abboud Cynthia. "Contrôle peptidergique de la douleur : modulation des voies descendantes par les systèmes relaxine." Thesis, Bordeaux, 2021. http://www.theses.fr/2021BORD0133.
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La douleur chronique souvent accompagnée d’anxiété et de dépression est un fléau mondial. La modulation de la douleur par les neuropeptides (NP) est bien connu au niveau des afférences primaires et de la moelle épinière. Peu de données sont toutefois disponibles sur leur rôle dans la douleur dans le cerveau. La famille relaxine comprend la relaxine, présente dans le système nerveux central (SNC) et qui possède des propriétés antifibrotiques, et la relaxine-3, strictement exprimée dans le SNC et qui présente des effets anxiolytiques et antidépressifs. Notre objectif est d’étudier la modulation de la douleur par les neuropeptides relaxine et relaxine-3 dans un modèle de douleur inflammatoire persistante chez la souris.Nos résultats démontrent que non seulement le système relaxine-3 / RXFP3, mais aussi le système relaxine / RXFP1 encore très peu exploré dans le SNC, ont des effets analgésiques en conditions de douleur inflammatoire. Les sites d'action de ces systèmes peptidergiques comprennent des régions corticales (cortex cingulaire, claustrum) et sous-corticales (amygdale) qui régulent les voies descendantes et l'intégration sensorielle dans la moelle épinière. Nos données mettent en évidence le potentiel thérapeutique de cette famille peptidergique dont les rôles dans la douleur n'avaient jamais été testésChronic pain often accompanied by anxiety and depression is a global scourge. The modulation of pain by neuropeptides (NP) is well known at the level of primary afferents and the spinal cord. However, little data is available on their role in pain in the brain. The relaxin family includes relaxin, which is present in the central nervous system (CNS) and has antifibrotic properties, and relaxin-3, which is strictly expressed in the CNS and has anxiolytic and antidepressant effects. Our objective is to study the modulation of pain by the neuropeptides relaxin and relaxin-3 in a mouse model of persistent inflammatory pain.Our results show that not only the relaxin-3 / RXFP3 system, but also the relaxin / RXFP1 system, which is still poorly explored in the CNS, have analgesic effects in conditions of inflammatory pain. The sites of action of these peptide systems include cortical (cingulate cortex, claustrum) and subcortical (amygdala) regions that regulate descending pathways and sensory integration in the spinal cord. Our data highlight the therapeutic potential of this peptide family, whose role in pain has never been tested before
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Gerab, Flavio Karpinscki. "Ilusões temporais: um estudo sobre percepção de tempo em função de contingências de reforçamento e punição, a partir do relato verbal." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-14052014-153224/.
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As alteracoes na percepcao da passagem do tempo dos seres humanos tem sido investigadas em relacao as caracteristicas de diversos estimulos, condicoes corporais ou determinados tipos de tarefa. Porem, pouco se sabe sobre essas alteracoes como funcao das contingencias reforcadoras ou punitivas que controlam o comportamento. Este estudo visou investigar essa questao experimentalmente atraves do uso de um jogo virtual em computador simulando percursos de um avatar em um labirinto com 36 situacoes de escolha entre esquerda e direita. Pontos poderiam ser ganhos ou perdidos, sendo a pontuacao final convertida em titulos de nobreza hipoteticos dentro de um ranking previamente estabelecido. Tres contingencias foram manipuladas: sob Punicao (P) escolhas erradas entre direita e esquerda produziam perda de pontos; sob Reforcamento (R) escolhas certas produziam ganho de pontos; na condicao Controle (C) nao havia alteracao nos pontos. No Experimento 1 (n=60), tres grupos foram manipulados, cada um exposto a uma dessas contingencias; no Experimento 1A (n=40) novos participantes passaram pelas condicoes P e R, porem com uma alteracao na instrucao explicitando o nao perigo de morte do avatar; no Experimento 2 (n=6), cada participante foi exposto as tres condicoes experimentais, sendo manipulada a ordem de exposicao: C-P-R e C-R-P. Cada participante foi solicitado a estimar o tempo que permaneceu jogando: nos dois primeiros estudos essa solicitacao foi feita apenas apos o termino do jogo (estimativa retrospectiva); no ultimo os participantes foram informados ao inicio da primeira sessao experimental que essa solicitacao lhes seria feita ao final de cada sessao (estimativa prospectiva). Da mesma forma, ao final da sessao no Experimentos 1 e 1A, e ao final de cada sessao no Experimento 2, foi solicitada aos participantes uma avaliacao do jogo, com pontuacoes crescentes proporcionais ao grau de diversao em joga-lo. Os resultados mostraram que no Experimento 1 a condicao P produziu tempo de sessao maior que na condicao C e a condicao R produziu tempo de sessao menor do que na condicao C, sendo que no Experimento 1A as diferencas se reduziram; no Experimento 2 esse tempo foi sendo reduzido na sucessao das contingencias, independente da ordem utilizada. Nos experimentos 1 e 1A os participantes superestimaram a duracao da sessao de jogo na condicao R, e as condicoes C e P produziram estimativas proximas a duracao real. No Experimento 2 a condicao R tambem esteve associada a superestimativas na maioria dos participantes, porem sua relacao com os resultados obtidos em C e P varia entre os participantes. A magnitude da consequencia se mostrou uma variavel relevante no efeito da punicao, que foi menos acentuado no Experimento 1A. A apreciacao do jogo pelos sujeitos foi, no geral, mais positiva para a condicao P. Esses resultados apontam a interacao das contingencias operantes na percepcao temporal, sendo discutida tambem a aparente independencia entre o efeito operante da punicao e o relato verbal sobre a diversao inerente a atividade consequenciadaAlterations in the perception of the passage of time in humans have been investigated in relation to the characteristics of several stimuli, bodily conditions and certain types of task. However, little is known about these alterations as a function of reinforcing or punishing contingencies that control behavior. This study aimed to investigate this question experimentally by using a virtual computer game simulating a maze in which an avatar was faced with 36 choice situations between left and right. Points could be won or lost, the final score being converted into hypothetical titles of nobility within a predetermined ranking. Three contingencies were manipulated: under Punishment (P) \"wrong \" choices between right and left produced loss of points; under Reinforcement (R) \"right\" choices produced gain points; under control condition (C) there was no change in points at all. In Experiment 1 (n=60), three groups were manipulated, each exposed to one of these contingencies, in Experiment 1A (n=40) new participants were exposed to the conditions P and R, but with a statement explaining that there was no chance of avatar\'s death during the game, in Experiment 2 (n=6), each participant was exposed to three experimental conditions, having the sequence of exposure being manipulated: C-P-R for half the participants and C-R-P for the other half. Each participant was asked to estimate the duration spent playing: in the first two studies this request was made just after the end of the game (retrospective estimation), at the last study participants were informed at the beginning of the first experimental session that this request would be made to them end of each session (prospective estimate). Similarly, at the end of the session in Experiments 1 and 1A, and at the end of each session in Experiment 2, participants were requested a review of the game, with scores increasing with the degree of fun playing it. The results showed that in Experiment 1 the condition P produced greater session length than the condition C, and condition R produced lesser session length than condition C, whereas in Experiment 1A differences are reduced; in Experiment 2 session length was being reduced along the succession of contingencies, regardless of the sequence used. In Experiments 1 and 1A participants overestimated the duration of the game session under the condition R, and C and P conditions produced close to the actual duration estimates. In Experiment 2 the R condition was also associated with overestimation in the majority of participants, however its relationship to the results obtained in C and P varies between participants. The magnitude of the result proved to be a relevant variable in the effect of punishment, which was less pronounced in Experiment 1A. The enjoyment of the game by the subjects was generally more positive for condition P. These results indicate the interaction of operant contingencies on time perception, and also discussed the apparent independence between the operant effect of punishment and verbal report about the fun inherent in activity that was punished
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Kaya, Ibrahim. "Relay feedback identification and model based controller design." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299955.
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Moore, Brian M. "Flexible multibody dynamics and control of the bifocal relay mirror." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FMoore.pdf.
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Thesis (Aeronautical and Astronautical Engineer and M.S. in Astronautical Engineering)--Naval Postgraduate School, December 2003.Thesis advisor(s): Brij N. Agrawal, Marcello Romano. Includes bibliographical references (p. 59). Also available online.
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Pandey, Sony. "Does altered expression of growth control genes relate to WT1 in leukemia?" Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1461592576.
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Thompson, Adam Craig. "The Future of Substations: Centralized Protection and Control." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73177.
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Modern power substations continue to use hardware that is dated and resistant to modernization. This document discusses the basics of substations, identifies their weaknesses, and suggests a method of improvement. This suggestion implements a centralized protection and control system to make the overall system more robust and flexible to the ever changing power system landscape.Master of Science
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Wu, Victor Kai Yuen. "OFDM-based cooperative communications in a single path relay network and a multiple path relay network." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11092006-152421/.
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Taylor, William Patrick. "The design and fabrication of fully integrated magnetically actuated micromachined relays." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/13345.
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Dewadasa, Jalthotage Manjula Dinesh. "Protection of distributed generation interfaced networks." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/43681/1/Jalthotage_Dewadasa_Thesis.pdf.
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With the rapid increase in electrical energy demand, power generation in the form of distributed generation is becoming more important. However, the connections of distributed generators (DGs) to a distribution network or a microgrid can create several protection issues. The protection of these networks using protective devices based only on current is a challenging task due to the change in fault current levels and fault current direction. The isolation of a faulted segment from such networks will be difficult if converter interfaced DGs are connected as these DGs limit their output currents during the fault. Furthermore, if DG sources are intermittent, the current sensing protective relays are difficult to set since fault current changes with time depending on the availability of DG sources. The system restoration after a fault occurs is also a challenging protection issue in a converter interfaced DG connected distribution network or a microgrid. Usually, all the DGs will be disconnected immediately after a fault in the network. The safety of personnel and equipment of the distribution network, reclosing with DGs and arc extinction are the major reasons for these DG disconnections. In this thesis, an inverse time admittance (ITA) relay is proposed to protect a distribution network or a microgrid which has several converter interfaced DG connections. The ITA relay is capable of detecting faults and isolating a faulted segment from the network, allowing unfaulted segments to operate either in grid connected or islanded mode operations. The relay does not make the tripping decision based on only the fault current. It also uses the voltage at the relay location. Therefore, the ITA relay can be used effectively in a DG connected network in which fault current level is low or fault current level changes with time. Different case studies are considered to evaluate the performance of the ITA relays in comparison to some of the existing protection schemes. The relay performance is evaluated in different types of distribution networks: radial, the IEEE 34 node test feeder and a mesh network. The results are validated through PSCAD simulations and MATLAB calculations. Several experimental tests are carried out to validate the numerical results in a laboratory test feeder by implementing the ITA relay in LabVIEW. Furthermore, a novel control strategy based on fold back current control is proposed for a converter interfaced DG to overcome the problems associated with the system restoration. The control strategy enables the self extinction of arc if the fault is a temporary arc fault. This also helps in self system restoration if DG capacity is sufficient to supply the load. The coordination with reclosers without disconnecting the DGs from the network is discussed. This results in increased reliability in the network by reduction of customer outages.
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Canevet, David. "Architectures électroactives polyfonctionnelles à base tétrathiafulvalène : Xérogels conducteurs et contrôle conformationnel à travers les relais calixarène et biphényle." Phd thesis, Université d'Angers, 2010. http://tel.archives-ouvertes.fr/tel-00492345.
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Le tétrathiafulvalène (TTF) est un composé organique remarquable de par la simplicité de sa structure et la diversité de ses applications. Depuis près d'une quarantaine d'années, ce donneur d'électrons-π a stimulé la recherche autour de matériaux cristallins conducteurs voire supraconducteurs. Tout récemment, le TTF a fait son apparition dans de nouveaux types de matériaux organiques, les organogels. La première partie de ce travail décrit la conception et l'optimisation structurale des premiers précurseurs d'organogels multifonctionnels à base TTF. L'étude des différents paramètres structuraux gouvernant la formation des organogels et la caractérisation des xérogels correspondants, par différentes techniques de microcopie, est présentée. La robustesse de ces gels est illustrée par leur persistance après oxydation à l'iode, fournissant des xérogels conducteurs. La présence d'unités pyrène au sein des molécules gélifiantes a également permis une incorporation maîtrisée de nanotubes de carbone simple paroi (NTC). Ces premiers exemples de xérogels conducteurs intégrant des NTCs présentent une morphologie et des propriétés conductrices remarquablement modifiées par rapport aux gels qui en sont dépourvus, traduisant un effet positif de structuration du gel par les NTCs. La multifonctionnalité de ces composés associant sites redox, de complexation et fluorophores, leur confère également un intérêt vers la préparation de portes logiques moléculaires, pour lesquelles une étude des paramètres initiaux (électrochimie, fluorescence) est réalisée. La seconde partie de ce travail s'inscrit dans la continuité, par la synthèse de différentes architectures moléculaires conformationnellement flexibles, associant le TTF et différents motifs accepteurs ou fluorophores sur la périphérie d'édifices calix[4]arène ou biphényle. Différents aspects du comportement dynamique de ces systèmes, ainsi que la synthèse de nouvelles briques moléculaires sont explorés.
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Campestrini, Lucíola. "Sintonia de controladores PID descentralizados baseada no método do ponto crítico." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/8187.
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Controladores PID são largamente utilizados no controle de processos industriais, tanto em sistemas monovariáveis como em sistemas multivariáveis. No entanto, muitos dos controladores encontrados na indústria são mal sintonizados. Um dos métodos mais simples de sintonia de controladores PID consiste em identificar algumas grandezas, as quais se relacionam com características do processo a controlar, e em seguida aplicar fórmulas para os parâmetros dos controladores baseadas nestas grandezas. Estas grandezas são o ganho e o período críticos do processo, os quais se relacionam diretamente com o limite de estabilidade do sistema. Uma característica bastante interessante deste método é que o mesmo pode facilmente ser implementado por um controle auto-ajustável. Por este fato, métodos de auto-ajuste destes controladores têm sido bastante utilizados em sistemas monovariáveis, através do uso do método do relé como procedimento de obtenção das grandezas críticas, necessárias à sintonia dos controladores. O método do relé consiste em aplicar um controle bang-bang em malha fechada com o processo do qual se quer identificar as grandezas críticas. Este procedimento, dentro de certas condições, provoca uma oscilação sustentada na saída do processo, da qual as grandezas críticas são obtidas. Tendo como objetivo o auto-ajuste de controladores PID em sistemas multivariáveis, o método do relé também pode ser utilizado para obtenção das grandezas críticas, devidamente adequado de maneira a obter as grandezas críticas multivariáveis do processo. Diferentes procedimentos de ensaios com relés podem ser aplicados em sistemas multivariáveis, porém somente um destes procedimentos é capaz de identificar as grandezas críticas multivariáveis do processo diretamente: o ensaio descentralizado com relés. Mesmo assim, a sintonia proposta na literatura é baseada nas fórmulas monovariáveis de Ziegler-Nichols e afins, mostrando-se, muitas vezes, inadequada. Desta forma, este trabalho tem o objetivo de apresentar um método de ajuste multivariável para controladores PID descentralizados, baseado nas grandezas críticas do processo. Este método estende o método do ponto crítico para sistemas monovariáveis aos sistemas multivariáveis, através da análise multivariável do problema. A análise do método do ponto crítico para sistemas monovariáveis mostra que um controlador PI ou PID sintonizado pelas fórmulas baseadas nas grandezas críticas do processo sempre irá deslocar o ponto crítico do processo para um outro ponto no plano complexo, determinado pelas fórmulas utilizadas. Da mesma forma, o método de sintonia proposto neste trabalho desloca o ponto crítico do processo para outro ponto no plano complexo, escolhido a priori, alterando a freqüência crítica do sistema.PID controllers are widely used in process control, in singlevariable systems as well as in multivariable ones. Yet, many of the controllers found in industry are poorly tuned. One of the simplest tuning method of PID controllers consists in identifying some values which are related to the process characteristics, and simply apply some formulae based on these quantities to determine the parameters of the controllers. Theses quantities are the ultimate gain and the ultimate period of the process, which are directly related to the system stability limit. A very interesting characteristic of this method is that it is easily implemented by an auto-tuning control. Thus, auto-tuning methods of this kind of controllers have been largely used in singlevariable systems, using the relay feedback experiment in order to obtain the ultimate quantities, which are needed to tune the controllers. The relay feedback experiment consists in applying a bang-bang control to the process from which the ultimate quantities are to be identified. This procedure, under some conditions, provides a sustained oscillation in the process’ output, from which the ultimate quantities are obtained. Aiming at auto-tuning of PID controllers in multivariable systems, the relay feedback experiment can also be used in order to get the ultimate quantities. Different relay feedback procedures can be applied to multivariable processes, but only one of these can identify the real multivariable ultimate quantities, formally considering the multivariable nature of the process: the decentralized relay feedback (DRF). However, the tuning of the controllers proposed in the literature is based on Ziegler-Nichols like formulae, what seems to be, many times, inappropriate. This work presents a multivariable tuning method of decentralized PID controllers, based on the process’ ultimate quantities. This method extends the ultimate point method used in SISO systems to multivariable ones, through multivariable analysis of the problem. The analysis of the ultimate point method used in singlevariable systems shows that a PI or PID controller tuned through formulae based on the process’ ultimate quantities will always dislocate the ultimate point to another point in the complex plane, determined by the used formulae. The tuning method proposed in this work dislocates the process’ ultimate point of a multivariable process to another point in the complex plane, chosen a priori, modifying the system’s ultimate frequency.
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Ferssiwi, Abdesslam. "Contrôle hypothalamique des processus de renforcement dans un relai gustatif, l'aire parabrachiale." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376050357.
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Williams, Dana Albert. "Feasibility of meteor burst buoy relay as a command and control asset." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23898.
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Approved for public release; distribution is unlimitedMeteor burst communication is currently being researched as a survivable, backup means to long-range communications due to a preceived vulnerability to HF and satellite communications. A specific hypothetical link that is analyzed in this thesis is that of a meteor burst relay network. The network consists of fixed land facilities, permanently moored ocean buoys, and air-deployable buoys, all in support of deployed submarines. The advantage of such a system for the submarine fleet is that it would allow the ability of establishing communications while maintaining a covert posture on-station. This is due to the meteor burst phenomenon of scattering, where a meteor trail projects a small ground illumination footprint, as compared to HF communications. As a result, a meteor burst channel has inherent characteristics that are resistant to ground based interception and jamming.
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Lee, Chee-Heng. "Integrated dynamic bandwidth allocation and congestion control in satellite frame relay networks." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/35957.
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Moʾin, Ali. "Computer aided design and analysis of nonlinear phenomena in relay control systems." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296527.
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Marklind, Anton, and Simon Marklind. "Relay-attacker : Utnyttjande av trådlösa bilnycklar." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-40262.
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Bilen är en av de saker som många människor använder dagligenoch för att underlätta användandet kommer det hela tiden nya funk-tioner som underlättar användandet. Ett exempel är trådlösa nycklar.Många moderna bilar använder en teknik som kallas för “keyless” vilketinnebär att bilnycklarna under intervaller sänder ut radiosignaler. Detger en möjlighet att inte behöva hålla i nyckeln när bilen ska användasoch bilägaren har det lättare att öppna bilen och lasta in saker, utanatt aktivt behöva använda nycklen.Men är det tillräckligt säkert med helt trådlösa nycklar? Signaler-na är öppen för alla som kan avlyssna dem. Signalerna mellan bil ochnyckel skickas trådlöst och obehöriga kan lyssna av innehållet. I dettaprojekt undersöker vi möjligheten att spela in signalen och därefterspela upp den igen i syfte att låsa upp en bil, utan tillgång till denverkliga nyckeln. Vi utför experiment på X fordon, med olika nycklaroch olika signalfrekvenser. Om det är öppet för alla borde det ock-så gå att spela in dessa signaler och sända ut dem med hjälp utaven radiosändare. Det kallas för en relay-attack och där kommer syftetmed detta arbete, nämligen en studie om hur attackerna går till ochhur enkelt det egentligen är att göra dem själva. Samt att ett experi-ment utförs på en mängd olika bilar med olika typer av bilnycklar medvarierande frekvenser.On a daily basis the car is frequently used, and a lot of people arein need of their cars. New technologies are developed to make it easierfor car owners to unlock the car and drive away without making theeffort of using the car keys. A technology called “keyless” car keys areimplemented in modern cars, the car keys sends out radio frequenciesin an interval on a couple of seconds.But is a complete wireless key system secure enough? The radiosignals are open to whoever wants to listen to them, and that couldhave devastating consequences. If it is open to everyone, then it shouldalso be possible to record these signals and send them out using a radiotransmitter. It’s called a relay attack and the purpose of this report isto get broader perspective of how an attack like that works and howeasy it is to execute the attack. The experiment was performed ondifferent types of cars and their keys with varying frequencies.
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Burgoyne, Vicky. "L'alliance thérapeutique en psychothérapie interculturelle, telle que relatée par des psychologues québécois." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5421.
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Les psychologues québécois sont de plus en plus amenés à intervenir auprès d'une clientèle de diverses origines ethniques, notamment dans la métropole que constitue la grande région montréalaise. Ceux-ci se trouvent ainsi souvent à adapter leurs interventions en fonction de divers cadres de référence culturels. Dans un contexte de psychothérapie interculturelle, les difficultés provenant des différences culturelles du psychothérapeute et du client d'origine ethnique différente peuvent entraver la qualité de la relation thérapeutique et, par conséquent, nuire à l'efficacité du processus thérapeutique. La connaissance de la perspective des professionnels est donc importante afin d'améliorer la qualité des interventions offertes à de tels clients. Ainsi, l'objectif général de la présente étude est de mettre en évidence et de mieux comprendre le vécu expérientiel de psychologues en lien avec l'alliance thérapeutique en contexte de psychothérapie interculturelle, et ce, par la voie d'une recherche qualitative. Aussi, de façon plus spécifique, les objectifs de cette recherche sont d'explorer l'expérience de psychologues québécois qui reçoivent des clients d'une origine ethnique différente de la leur, notamment de façon à: 1) en cerner les particularités; 2) relever les facteurs liés à la diversité culturelle qui peuvent nuire à l'établissement et au maintien de l'alliance thérapeutique; 3) identifier les stratégies adaptatives qu'adoptent ces psychologues pour contrer les obstacles à l'alliance thérapeutique liés à la différence culturelle. À cette fin, 8 psychologues québécois, pratiquant la psychothérapie interculturelle de type individuel avec une clientèle adulte dans la grande région de Montréal, ont été rencontrés dans le cadre d'entrevues individuelles semi-structurées. Une analyse thématique des données recueillies a permis de cerner différents aspects signifiants dans la relation thérapeutique interculturelle, lesquels sont classés en six grandes catégories: 1) la perception du psychologue de la relation thérapeutique avec un client d'origine ethnique différente; 2) la perception du psychologue de son rôle en tant que professionnel; 3) les contributions du client et du psychologue à l'alliance thérapeutique en contexte de psychothérapie interculturelle; 4) les obstacles à l'alliance thérapeutique; 5) les stratégies adaptatives du psychologue pour contrer les obstacles à l'alliance thérapeutique; 6) les aspects positifs rencontrés par le psychologue dans l'expérience de la relation psychologue-client en intervention interculturelle. Un cadre d'analyse psychodynamique permet d'exposer les transferts et contre-transferts personnels et culturels qui influencent la relation thérapeutique interculturelle. Malgré certaines limites méthodologiques, tel le nombre restreint de l'échantillon ou certains inhibiteurs affectant la capacité des participants à relater leur expérience, les propos recueillis tracent un portrait riche des enjeux qui peuvent affecter l'établissement et le maintien de l'alliance thérapeutique en contexte interculturel. Plusieurs avenues de recherche sont suggérées, à la lumière de la présente étude.
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Johnson, Scott L. "Beam control of extremely agile relaying laser source for bifocal relay mirror spacecraft." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Sep%5FJohnson_Sc.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2006.Thesis Advisor(s): Brij Agrawal. "September 2006." Includes bibliographical references (p. 91). Also available in print.
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Ansari, Rukhsana 1971 Carleton University Dissertation Engineering Systems and Computer. "Compressed voice in integrated services frame relay networks: voice synchronization and congestion control." Ottawa.:, 1995.
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Roslon, Ewa. "Relay cropping of spring barley and winter wheat /." Uppsala : Dept. of Ecology and Crop Production Science, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a427-ab.html.
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Kilic, Eda. "Quality Of Service Aware Dynamic Admission Control In Ieee 802.16j Non-transparent Relay Networks." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611631/index.pdf.
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Today, telecommunication is improving rapidly. People are online anywhere anytime. Due to
increasing demand in communication, wireless technologies are progressing quickly trying to
provide more services in a wide range. In order to address mobility and connectivity requirements
of users in wide areas, Worldwide Interoperability for Microwave Access (Wimax) has
been introduced as a forth generation telecommunication technology.
Wimax, which is also called Metropolitan Area Network (MAN), is based on IEEE 802.16
standard where a Base Station (BS) provides last mile broadband wireless access to the end
users known as Mobile Stations (MS). However, in places where high constructions exist,
the signal rate between MS and BS decreases or even the signal can be lost completely due
to shadow fading. As a response to this issue, recently an intermediate node specification,
namely Relay Station, has been defined in IEEE 802.16j standard for relaying, which provides
both throughput enhancement and coverage extension. However, this update has introduced a
new problemcall admission control in non-transparent relay networks that support coverage extension. In this thesis, a Quality of Service (QoS) aware dynamic admission control algorithm for IEEE 802.16j non-transparent relay networks is introduced. Our objectives are admitting more service flows, utilizing the bandwidth, giving individual control to each relay station (RS) on call acceptance and rejection, and finally not affecting ongoing service flow quality in an RS due to the dense population of service flows in other RSs. The simulation results show that the proposed algorithm outperforms the other existing call admission control algorithms. Moreover, this algorithm can be interpreted as pioneer call admission control algorithm in IEEE 802.16j non-transparent networks.
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Vichare, Nitin Shrikrishna. "Measurement and modelling of errors for relaying current transformers and voltage transformers." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42139.
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A measurement tool has been developed to estimate errors in relaying current transformers and voltage transformers. The tool has been developed to collect data in a substation and send it to a remote location over a telephone line. Different schemes were evaluated and tested in the laboratory. The final choice was made on the basis of the hardware and transmission cost constraints.
The measurement unit was developed using hardware similar to that used in a computer relay. The signals from the current and voltage transducers were sampled using a microprocessor and an analog to digital converter in real-time. The measurement device has been installed in the field. The data from the field was collected remotely and analyzed in the Virginia Tech Power Systems laboratory. The analysis of the data is presented at the end.Master of Science
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Olsson, Markus. "Simulation Comparison of Auto-Tuning Methods for PID Control." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11106.
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Auto-tuning has become an important function in distributed control systems (DCS) and is especially appreciated in large industries that can have hundreds of controllers. In the DCS 800xA manufactured by ABB, there is an auto-tuning method implemented based on a relay experiment to determine the ultimate gain and the ultimate period, with which the PID parameters are obtained using the modified Ziegler-Nichols tuning rules. The tuning procedure can then proceed with a step identification experiment to get additional parameters for kappa-tau tuning. In the previous DCS, called Advant, there was another auto-tuning approach implemented. This method was based on dominant pole design, which included an identification of the process. The purpose of this thesis is to compare these auto-tuning methods, to investigate if the dominant pole placement method should be migrated to the 800xA system.
Automatisk trimning har blivit en viktig funktion i distribuerade styrsystem (DCS och är speciellt av intresse för stora industrier som kan ha flera hundra regulatorer. Den automatiska trimningen som idag är implementerad i ABB:s DCS 800xA är baserad på ett reläexperiment för att bestämma den ultimata förstärkningen och den ultimata periodtiden. Modifierade Ziegler-Nichols trimningsregler används sedan för att bestämma PID parametrarna. Vidare kan trimningen fortsätta med ett stegsvars-experiment för att erhålla ytterliggare parametrar och trimma med kappa-tau metoden. Den automatiska trimningsmetoden som var implementerad i tidigare DCS, Advant, var baserad på dominant polplacering med identifiering av processen. Syftet med detta examensarbete är att jämföra dessa automatiska trimningsmetoder för att undersöka om den tidigare trimningsmetoden baserad på dominant polplacering ska implementeras i 800xA systemet.
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Paris-Ficarelli, Natacha. "Magistrats en réseaux contre "la criminalité organisée" : l'Appel de Genève, genèse et relais politiques en Europe /." Strasbourg : Presses universitaires de Strasbourg, 2008. http://catalogue.bnf.fr/ark:/12148/cb41370414c.
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Santos, André Henrique Lameira dos, and 92992384056. "Identificação e Controle de Altitude de um Quadrirrotor." Universidade Federal do Amazonas, 2018. https://tede.ufam.edu.br/handle/tede/6639.
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In this work approaches the development altitude control for a low-cost quadrotor vehicle. The identification of the model of the altitude dynamics of the quadrotor using the relay method is presented. This method is also a tool in the tuning of a PID controller implemented for dynamics model. Comparisons of controller performances, designed for the identified and mathematically modeled plant, were analyzed, in addition to the performance of the controller tuned by the Relay direct method, without the need for the altitude model. In the experiments, transient response performance parameters were evaluated for a step-type reference input. In addition, the behavior of the compensated altitude for a trapezoidal reference trajectory was evaluated. The results showed that the technique employed is, besides simple, efficient for this type of system.
Neste trabalho é abordado o desenvolvimento de um controlador de altitude para um veículo quadrirrotor de baixo custo. A identificação do modelo da dinâmica de altitude do quadrirrotor é realizada utilizando o método do relé. Esse método também é uma ferramenta de auxílio na sintonia de um controlador PID implementado para modelo da dinâmica. Comparações dos desempenhos do controlador, realizados para a planta identificada e modelada matematicamente, foram analisadas, além do desempenho do controlador sintonizado pelo método direto do Relé, esse sem a necessidade do modelo de altitude. Nos experimentos foram avaliados parâmetros de desempenho da resposta em regime transitório para uma entrada de referência do tipo degrau. Além disso, foi avaliado o comportamento da altitude compensada para uma trajetória de referência trapezoidal. Os resultados mostraram que a técnica empregada é, além de simples, eficiente para este tipo de sistema.
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Chernesky, Vincent S. "Development and control of a three-axis satellite simulator for the bifocal relay mirror initiative." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA401293.
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Thesis (M.S. in Astronautical Engineering) Naval Postgraduate School, December 2001.Thesis Advisor(s): Spencer, Michael G. ; Agrawal, Brij N. "December 2001." Includes bibliographical references (p. 85-86). Also available in print.
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Zhang, Shu Carleton University Dissertation Engineering Systems and computer. "Congestion control in frame relay networks with variable bit rate compressed voice and data traffic." Ottawa, 1993.
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Spatti, Danilo Hernane. "Sistema inteligente para controle de relés reguladores de tensão." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-29032007-103518/.
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Este trabalho apresenta uma estratégia para realizar o controle de tensão em um sistema de distribuição de energia elétrica dotado de comutadores de tap sob carga. Será investigada a aplicação de sistemas inteligentes para tornar os relés reguladores de tensão mais flexíveis. A inserção de módulos inteligentes em relés reguladores de tensão convencionais irá permitir um melhor aproveitamento das funcionalidades já existentes destes dispositivos. Ainda como foco do estudo, pretende-se atuar apenas na subestação de distribuição, realizando medições no barramento secundário e tomando medidas de controle também neste barramento. A capacidade dos sistemas fuzzy em tratar informações incertas, bem como sua potencial aplicabilidade em problemas tendo comportamentos não previsíveis, permitiram a criação de uma estratégia de controle de tensão que atende todas as regulamentações dos órgãos fiscalizadores e, também, os anseios das concessionárias de distribuição de energia elétrica devido aos resultados promissores obtidos em simulação com dados reais das subestações.This work presents an approach to voltage control in power distribution systems with load tap changers. Intelligent approaches are studied and applied in voltage regulator relay in order to improve the voltage profiles of the system. The proposal of this work is the addition of fuzzy modules in the conventional voltage regulator relays, which allows the exploration of the main functionalities already implemented in such devices. The adaptive fuzzy voltage regulator relay controls the voltage in the distribution substation, monitoring electrical variables and performing the regulation on secondary bus based on the results provided by the fuzzy modules, which are capable to take into account the voltage profile standards for distribution systems as well as operational interests defined by electrical distribution companies. Simulation results using real data from substations are presented to validate the proposed approach.
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Anderson, Sharon Lee. "Reduced order power system models for transient stability studies." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09052009-040743/.
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Dutton, David Moreton. "Controls on the genesis, evolution and be=reaching of relay ramps : examples from offshore West Africa." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424469.
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Junior, José Roberto Caon. "Controladores PID industriais com sintonia automática por realimentação a relê." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-04042001-172532/.
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O presente trabalho tem por objetivo a implementação de algoritmos de controle do tipo PID com sintonia automática de seus parâmetros para controle de processos térmicos de primeira ordem mais tempo morto. Existe um grande número de métodos para a sintonia automática, os quais requerem informações variadas sobre o processo. A sintonia automática dos parâmetros do controlador escolhida para implementação é baseada no método da realimentação a relê que utiliza o ganho estático e o período e amplitude críticos do processo e pode ser facilmente adotada na indústria. Este método foi implementado em um controlador industrial microprocessado que utiliza um microcontrolador da família 8051. A correta identificação dos parâmetros críticos do processo presume a geração de oscilações simétricas durante a realimentação a relê. O algoritmo de sintonia automática desenvolvido inclui correção em tempo real da amplitude do relê para evitar identificação falsa de um ciclo da oscilação e da assimetria na saída do processo durante a realimentação a relê. A implementação do algoritmo é simples e direta em termos de programação no ambiente de microcontroladores mesmo em linguagem de baixo nível (assembly). São apresentados resultados de simulação e os resultados experimentais realizados em um aparelho industrial comercial.The objective of this work is the implementation of a PID control algorithm with auto-tuning for a thermal first order process plus dead-time. There is a number of methods for the auto-tuning of PID controllers which require different information on the process. The auto-tuning algorithm is implemented in a industrial controller based on the 8051 microcontroller family. The auto-tuning method considered for implementation is based on the relay feedback procedure which require the process steady state gain and the ultimate point on the Nyquist plot and can be easily adopted by industry. The method is also suited for pre-tuning adaptive controllers. The auto-tuning method used assume symmetrical oscillations during the relay feedback experiment to render the correct ultimate point on the Nyquist plot The proposed auto-tuning algorithm includes on-line correction for asymmetry oscillation and relay amplitude to avoid false capture of the limit cycle. The symmetrical oscillations are ensured by a DC bias signal added to the relay output. The algorithm is simply and straight to be written in a microcontroller programming language. Experimental results accomplished in a industrial PID auto-tuner are presented.
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Brockway, Christine May. "Maternal control and its antecedents: an examination of monitoring and autonomy promotion as they relate to prior emotional availability." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406641253.
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