This thesis describes a study into the performance of both opening and closing switches, as used in pulsed-power networks. It also discusses the important energy storage and compression techniques that are used in the generation of high-energy pulsed power. Various different types of switches are involved in these applications, and particular consideration is paid to the performance of the MESS (Magnetic Energy Switching System) switch, used both in isolation and as part of a pulse-forming network. Exploding wires and foils are also investigated in some detail, since important features from the action of these are present in most opening switches.

Physical processes which are governed by differential equations or difference equations with discontinuous behavior can be modeled as jump systems. An important type of jump systems is the one evolving linearly among the discrete events; this type of systems is called jump linear systems. A common analysis approach is to employ stochastic processes to describe the sequences, switches, and statistic properties of the discrete events. In this thesis, the jump linear systems to be studied are governed by semi-Markov processes. This type of jump linear systems is called the semi-Markov jump linear system. Due to the nature of the jump linear system, it finds many applications in networked control systems, fault tolerant control systems, and other systems subject to abrupt changes. It is worthwhile to mention that the well studied Markov jump linear system is a special case of the semi-Markov jump linear system. The thesis consists of two parts: The analysis and synthesis of semi-Markov jump linear systems and networked dynamic systems. In Chapter 2 and Chapter 3, the stochastic stability and optimal control for semi-Markov jump linear systems with or without time delays are investigated. In Chapter 4, a novel fault tolerant control scheme is proposed based on the semi-Markov jump linear system stability conditions. Chapter 5 to Chapter 7 discuss the networked dynamic systems analysis via jump linear system approaches. The stochastic stability conditions for semi-Markov jump linear systems are firstly derived. The Lyapunov theory is used to establish the sufficient stability conditions by deriving the infinitesimal generator of the Lyapunov function. Since in practice, almost all the system models could not be identified precisely, robust control problems for systems with uncertainties are investigated based on the established stability conditions. Considering the potential applications on networked systems where time delays are inevitable, optimal control problems for systems with time-varying delays have been studied. In the fault tolerant control design, the semi-Markov process is ideal to characterize time-varying failure rates of the system components whose life time is not exponentially distributed. The designed controller is capable of maintaining the stability when an actuator malfunctions. In the networked control system analysis, stochastic processes are used to model time delays and sensor scheduling rules. Network limitations are compensated by considering more historical information or planning for all possible delays that happen in the future. Both simulations and experiments show the improvements of the control performance by using the proposed techniques. A networked haptic system is investigated via the switching system approach. In the haptic system, the avatar interacts one-dimensionally with a multi-material virtual wall in the virtual environment.The random trajectory along which the avatar moves upon the wall is modeled by stochastic processes, then the multi-material virtual wall rendering is achieved. Finally, the thesis work is summarized and two future research topics are proposed. One is on the networked control system design where delays are modeled by semi-Markov processes, and the other one is on the event-trigger scheme design for networked dynamic systems. / Graduate / 0548 / 0544 / 0546 / jihuang@uvic.ca

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the status of the Edwards Digital Switch (EDS) [1] and the success of the Digital Switch Sustainment Program (DSSP); a multi-service program aimed at cost-effective means for providing maintenance and development of an advanced digital switching system. This digital communications switching system is deployed at the mission control centers of Edwards AFB, Eglin AFB, and China Lake Naval Air Warfare Center (NAWC). Each system provides the test ranges with mission-critical voice communications and Time Space Position Information (TSPI) switching. Through user-friendly Graphical User Interfaces (GUIs), the switch provides exceptional resource management of radios, telephones, user positions, secure communications, radars, trackers, 4-wire Ear & Mouth (E&M) devices, subscriber services, and other equipment. Developed using commercial equipment, such as the Lucent Technologies Digital Access and Cross-Connect System (DACS) II, the digital switch can integrate and interface with the technologies of other test ranges and customers. The DSSP sustaining engineering contract, a $10M contract awarded in 1997, is a multi-service effort in supporting cost effective maintenance and enhancement for the systems’ software and hardware. Eglin and China Lake have agreed to participate in a Digital Switch Working Group (DSWG) to ensure that this configuration management is in place and that all players follow the same system migration path. These ranges and other interested ranges that agree to purchase systems off the contract and participate in the working group will continue to derive benefits by reducing overhead and eliminating the duplication of effort involved in separate endeavors.

No description available.

La théorie des systèmes a acquis un statut interdisciplinaire au cours des cinq dernières décennies, et un aspect important de cette théorie concerne la commande automatique des systèmes dynamiques. Un dispositif de commande, appelé contrôleur ou régulateur, est un dispositif qu'on interconnecte à un système donné, qu'on désigne aussi sous le terme de procédé ou processus, de manière à réaliser un système global ayant un comportement désiré ou des performances spécifiées. Dans cette thèse, nous traitons de la problématique de la commande automatique des systèmes dynamiques sujets à des défaillances. Cette problématique est fortement motivée par les exigences de sûreté de fonctionnement des systèmes en milieu industriel où la commande tolérante aux défauts constitue un moyen pour améliorer la fiabilité et accroître la disponibilté des systèmes tout en assurant les performances souhaitées. Le travail présenté dans cette thèse porte essentiellement sur la synthèse de techniques de commande en ligne en vue de garantir une tolérance aux pannes à tout moment pour le système bouclé. Deux approches sont proposées, à savoir une première approche basée sur une banque de contrôleurs pré-conçus et une seconde approche basée sur la conception en ligne des commandes. L'originalité de ces approches réside dans le fait qu'aucune information a priori sur le procédé n'est exigée ou n'est disponible en temps réel. En particulier, aucune identification ni estimation des paramètres du procédé n'est effectuée en temps réel. La reconfiguration des contrôleurs suite à une défaillance du procédé se base uniquement sur les trajectoires réelles (signaux) issues du procédé. Nous utilisons l'approche comportementale des systèmes comme paradigme de modélisation mathématique pour le développement des solutions proposées. Dans ce cadre mathématique, le concept d'interconnexion entre deux systèmes dynamiques, à savoir le contrôleur et le procédé, joue un rôle important dans la formulation et la solution du problème de commande et permet de déterminer l'ensemble admissible des trajectoires du procédé qui sont compatibles avec les spécifications de performance. Du point de vue pratique, la réduction des transitoires lors de la reconfiguration des contrôleurs est l'une des exigences importantes dans les algorithmes de commandes tolérantes aux défauts. La dernière partie de la thèse traite de la gestion de ces transitoires à l'aide d'une technique d'implantation des contrôleurs en temps réel qui assure une transition sans-à-coup lors des reconfigurations. En outre, on illustre dans cette dernière partie de la thèse les solutions de commandes obtenues pour la tolérance aux fautes sur des exemples issus du monde réel, à savoir un procédé hydraulique constitué de deux bacs à niveau, un avion en phase d'approche à l'atterrissage, et une éolienne NREL de 5 mégawatts / The field of system and control theory has achieved an interdisciplinary status during the past five decades, and we refer to the theory that was developed during this period as the conventional control theory. This mainly relates to the study of automation and the design of controllers. A controller is a device that makes the interconnection with a given system so that the controlled system can behave in a desired way. In this thesis, we deal with the issues when the controlled system becomes faulty. The control of a faulty system addresses the concept of Fault-Tolerant Control System (FTCS). The study of such systems is in response to the demands of large-scale industries since from their viewpoint it is the foremost task to design control systems, which are capable of tolerating potential faults occurring either in the internal closedloops or from the environmental factors in order to improve the reliability and availability of a system while providing the expected performance. The work presented in this thesis is mainly focused on synthesizing the online controllers that guarantee the closed-loop system to be fault-tolerant at anytime. Two methodologies are proposed in this work, which rest under the broad classification of FTC systems, namely projection-based approach and online redesign approach. The novelty of these approaches lies in the fact that any a priori information about the plant is not available in realtime. In addition, no online identification or estimation of the operating plant is carried out. Rather, the re-configuration procedure of the controllers is solely based on the measurements generated by the unknown plant. This phenomenon is very nicely demonstrated by using the time-trajectory based viewpoint of behavioral theory. Within this mathematical framework, the interconnection between two dynamical systems, namely the plant and the controller, plays the significant role. Consequently, taking the benefits of this behavioral framework, the real-time measurement based solutions are proposed to handle the fault-tolerant control problem. From the practical implementation viewpoint, the transient management during the controller reconfiguration mechanism is one of the important requirements for active FTCS. The last part of the thesis deals with the online implementation of the controllers within the behavioral framework, which takes care of the transient mechanism. The proposed approach guarantees the "real-time smooth interconnection" between the controller and the unknown plant. Moreover, in this part the application of the theory developed in the thesis is effectively demonstrated on real-world examples, namely the two-tanks system, the aircraft landing mechanism, and the NREL's 5MW wind turbine system.

We present a model of coupled transcriptional-translational ultradian oscillators (TTOs) as a possible mechanism for the circadian rhythm observed at the cellular level. It includes nonstationary Poisson interactions between the transcriptional proteins and their affined gene sites. The associated reaction-rate equations are nonlinear ordinary differential equations of stochastic switching type. We compute the deterministic limit of this system, or the limit as the number of gene-proteins interactions per unit of time becomes large. In this limit, the random variables of the model are simply replaced by their limiting expected value. We derive the Kolmogorov equations — a set of partial differential equations —, and we obtain the associated moment equations for a simple instance of the model. In the stationary case, the Kolmogorov equations are linear and the moment equations are a closed set of equations. In the nonstationary case, the Kolmogorov equations are nonlinear and the moment equations are an open-ended set of equations. In both cases, the deterministic limit of the moment equations is in agreement with the deterministic state equations.

We present a model of coupled transcriptional-translational ultradian oscillators (TTOs) as a possible mechanism for the circadian rhythm observed at the cellular level. It includes nonstationary Poisson interactions between the transcriptional proteins and their affined gene sites. The associated reaction-rate equations are nonlinear ordinary differential equations of stochastic switching type. We compute the deterministic limit of this system, or the limit as the number of gene-proteins interactions per unit of time becomes large. In this limit, the random variables of the model are simply replaced by their limiting expected value. We derive the Kolmogorov equations — a set of partial differential equations —, and we obtain the associated moment equations for a simple instance of the model. In the stationary case, the Kolmogorov equations are linear and the moment equations are a closed set of equations. In the nonstationary case, the Kolmogorov equations are nonlinear and the moment equations are an open-ended set of equations. In both cases, the deterministic limit of the moment equations is in agreement with the deterministic state equations.

Rapporten beskriver ett examensarbete genomfört på uppdrag av Motoman Robotics Europe AB i Torsås. Uppdraget gick ut på att hitta en lösning för att helautomatiskt kunna växla svetspistoler med en Motoman HP-20 industrirobot. Projektet har i första hand varit ett utvecklingsarbete med fokus på en fungerande praktisk lösning. Arbetet har fortskridit i nära samarbete med och handledning av konstruktörer på företaget samt stöd från vår lärare. Resultatet har blivit en kompakt och estetiskt tilltalande konstruktion som uppfyller kraven som uppdragsgivaren ställt. / The paper describes a final thesis carried out on assignment of Motoman Robotics Europe AB in Torsås, Sweden. The assignment was to find a solution for a fully automated switching of welding-guns with a Motoman HP-20 industrial robot. The project has formerly been a development-work with focus on a functioning practical solution. The work has proceeded in close cooperation and guidance from constructors at the company as well as support from our teacher. The result has given us a compact and ecstatically pleasing construction that fulfils the demands that the commissioner has ordered.

<p>Rapporten beskriver ett examensarbete genomfört på uppdrag av Motoman Robotics Europe AB i Torsås. Uppdraget gick ut på att hitta en lösning för att helautomatiskt kunna växla svetspistoler med en Motoman HP-20 industrirobot. Projektet har i första hand varit ett utvecklingsarbete med fokus på en fungerande praktisk lösning. Arbetet har fortskridit i nära samarbete med och handledning av konstruktörer på företaget samt stöd från vår lärare. Resultatet har blivit en kompakt och estetiskt tilltalande konstruktion som uppfyller kraven som uppdragsgivaren ställt.</p> / <p>The paper describes a final thesis carried out on assignment of Motoman Robotics Europe AB in Torsås, Sweden. The assignment was to find a solution for a fully automated switching of welding-guns with a Motoman HP-20 industrial robot. The project has formerly been a development-work with focus on a functioning practical solution. The work has proceeded in close cooperation and guidance from constructors at the company as well as support from our teacher. The result has given us a compact and ecstatically pleasing construction that fulfils the demands that the commissioner has ordered.</p>

Informationen des Universitätsrechenzentrums