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Kouvaros, Panagiotis. "Parameterised verification for multi-agent systems". Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/33793.
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In the past ten years several methods have been put forward for the efficient model checking of multiagent systems against agent-based specifications. Yet, since the number of states is exponential in the number of agents in the system, the model checking problem remains intractable for systems of many agents. This is particularly problematic when wishing to reason about unbounded systems where the number of components is not known at design time. Systems ranging from robotic swarms to e-commerce applications constitute typical examples in which the number of participants is independent of the design process. This thesis develops parameterised model checking techniques for the validation of multiagent systems irrespectively of the number of the agents present. To do this, a semantics that captures parameterised, synchronous multiagent systems and one that models parameterised, interleaved multiagent systems are introduced. Both semantics extend interpreted systems in a parameterised setting where the number of agents is the parameter. Parameterised model checking techniques for the semantical classes introduced are developed. A sound and complete cutoff methodology is studied for parameterised interpreted systems. A sound but incomplete cutoff procedure for parameterised interleaved interpreted systems is also studied. While the latter procedure is in exponential space, three notable subclasses are isolated and more effective verification techniques are put forward. The algorithms proposed are shown to be sound. For one class the decidability of the verification problem is shown and a complete cutoff procedure is discussed. Finally, the model checker MCMAS-P is introduced. The tool supports the verification of unbounded multiagent systems against temporal-epistemic specifications. MCMAS-P implements the procedures here developed; the procedure invoked depends on the properties of the system under examination. Experimental results obtained on cache coherence protocols, mutual exclusion protocols, swarm foraging algorithms, and swarm aggregation algorithms are reported.
2
Houhou, Sara. "Parameterised Verification from Formal Specifications of Information Systems". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS421.
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La vérification des modèles de processus métiers est cruciale pour permettre d'y détecter d'éventuelles erreurs dès la conception, plutôt qu'à l'exécution sur des moteurs de processus métier. BPMN est la notation principale pour la modélisation de processus métier. Il s'agit d'un standard ISO, largement utilisé à la fois en enseignement et dans l'industrie. La sémantique de BPMN est cependant définie de façon semi-formelle au sein du standard. C'est pourquoi de nombreux travaux se sont attaqués à la définition d'une sémantique formelle pour BPMN. Dans cette thèse, nous avons tout d’abord fourni une étude détaillée des principaux travaux portant sur la vérification de modèles BPMN. Cela nous a permis d'identifier plusieurs fragments de la notation qui sont souvent mis de côté dans les travaux de formalisation, tels que les différents modèles de communication, la gestion temporelle, ou le caractère multi-instance. Ces aspects sont pourtant cruciaux pour l'élargissement du domaine d'application de BPMN vers des cadres tels que l'Internet des Objets ou l'Usine du Futur. Nous avons alors défini une approche pour la vérification de modèles de collaboration de processus métiers qui supporte plusieurs de ces perspectives, à savoir les différents modèles de communication et les contraintes liées au temps. Pour cela nous avons défini une sémantique d'exécution formelle, en termes de logique du premier ordre, au fragment de BPMN pris en compte. Nous avons ensuite défini des implantations de cette sémantique dans les langages formels TLA+ et Alloy. Ceci a, enfin, permis la vérification des modèles à l'aide des outils dédiés à ces langages formels. Notre approche est supportée par un outil, fbpmn, permettant les transformation formelles de modèles BPMN vers TLA+ et Alloy, la vérification des modèles, et l'animation de contre-exemples lorsque les propriétés à vérifier ne sont pas satisfaites. Ce retour se fait directement sur le modèle BPMN initial ce qui rend l'approche praticable dans un contexte d'utilisation par des non-spécialistes des méthodes formelles. Une application Web a aussi été développée pour rendre encore plus aisée l'application de notre approche formelle dans un cadre industriel. Nos outils, nos implantations en TLA+ et Alloy de la sémantique formelle, et notre bibliothèque d'exemples sont open source et disponibles en ligneBusiness process models verification is crucial to detect possible errors at design time, rather than at execution on business process engines. BPMN is the primary notation for business process modelling. It is an ISO standard, widely used both in education and in industry. The semantics of BPMN are however defined in a semi-formal way within the standard. This is why many works have tackled the definition of formal semantics for BPMN. In this thesis, we first provided a detailed study of the main works relating to the verification of BPMN models. This allowed us to identify several fragments of the notation which are often put aside in the work of formalization, such as the different models of communication, the temporal management, or the multi-instance character. These aspects are however crucial for the extension of the field of application of BPMN to frameworks such as the Internet of Things or the Factory of the Future. We then defined an approach for the verification of business process collaboration models that supports several of these perspectives, namely the different communication models and time constraints. For this, we have defined formal execution semantics, in terms of first-order logic, to the BPMN fragment taken into account. We then defined implementations of this semantics in the formal languages TLA + and Alloy. Finally, this enabled the models to be verified using tools dedicated to these formal languages. Our approach is supported by a tool, fbpmn, allowing the formal transformation of BPMN models to TLA + and Alloy, the verification of models, and the animation of counter-examples when the properties to be verified are not satisfied. This feedback is done directly on the initial BPMN model which makes the approach practicable in a context of use by non-specialists of formal methods. A web application has also been developed to make it even easier to apply our formal approach in an industrial setting. Our tools, our TLA + and Alloy formal semantics implementations, and our library of examples are open sources and available online
3
Graham, Douglas. "Parameterised verification of randomised distributed systems using state-based models". Thesis, Connect to e-thesis, 2008. http://theses.gla.ac.uk/95/.
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Thesis (Ph.D.) - University of Glasgow, 2008.Ph.D. thesis submitted to the Faculty of Information and Mathematical Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.
4
Lehaut, Mathieu. "Synthesis for parameterized systems". Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS341.
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Cette thèse étudie le problème de la synthèse dans le cadre de systèmes distribués dont le nombre de participants n’est pas connu à l’avance et qui interagissent avec un environnement incontrôlable. Il s’agit alors de construire automatiquement un programme pour un tel système qui sera correct par construction vis à vis d’une spécification donné, si cela est possible. On étudie aussi le problème proche qu’est le contrôle, où il s’agit alors de construire un contrôleur pour un système déjà partiellement défini afin que tous les comportements de ce système soient corrects par rapport à la spécificationIn this thesis, we study the synthesis problem for distributed systems where the number of participants is not known in advance and in which all participants interact with an uncontrollable environment. The synthesis problem is about automatically generating a program for such a system that would be correct by construction for a given specification, if such a program exist. We also study the closely related control problem, whose goal is generating a controller for a partially defined system such that all behaviors generated are correct with respect to the specification
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Peach, Nigel G. "Bearings only tracking using a set of range parameterised extended Kalman filters". Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362303.
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Mahata, Pritha. "Model Checking Parameterized Timed Systems". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4835.
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Malak, Richard J. Jr. "Using parameterized efficient sets to model alternatives for systems design decisions". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26697.
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Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Paredis, Christiaan J.J.; Committee Member: Bras, Bert; Committee Member: Choudhary, Ruchi; Committee Member: McGinnis, Leon; Committee Member: Rosen, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Ben, Henda Noomene. "Infinite-state Stochastic and Parameterized Systems". Doctoral thesis, Uppsala University, Department of Information Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8915.
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A major current challenge consists in extending formal methods in order to handle infinite-state systems. Infiniteness stems from the fact that the system operates on unbounded data structure such as stacks, queues, clocks, integers; as well as parameterization.
Systems with unbounded data structure are natural models for reasoning about communication protocols, concurrent programs, real-time systems, etc. While parameterized systems are more suitable if the system consists of an arbitrary number of identical processes which is the case for cache coherence protocols, distributed algorithms and so forth.
In this thesis, we consider model checking problems for certain fundamental classes of probabilistic infinite-state systems, as well as the verification of safety properties in parameterized systems. First, we consider probabilistic systems with unbounded data structures. In particular, we study probabilistic extensions of Lossy Channel Systems (PLCS), Vector addition Systems with States (PVASS) and Noisy Turing Machine (PNTM). We show how we can describe the semantics of such models by infinite-state Markov chains; and then define certain abstract properties, which allow model checking several qualitative and quantitative problems.
Then, we consider parameterized systems and provide a method which allows checking safety for several classes that differ in the topologies (linear or tree) and the semantics (atomic or non-atomic). The method is based on deriving an over-approximation which allows the use of a symbolic backward reachability scheme. For each class, the over-approximation we define guarantees monotonicity of the induced approximate transition system with respect to an appropriate order. This property is convenient in the sense that it preserves upward closedness when computing sets of predecessors.
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Kojić, Aleksandar M. 1974. "Parameter estimation in nonlinearly parameterized systems". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47637.
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Rezine, Ahmed. "Parameterized Systems : Generalizing and Simplifying Automatic Verification". Doctoral thesis, Uppsala universitet, Avdelningen för datorteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8587.
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In this thesis we propose general and simple methods for automatic verification of parameterized systems. These are systems consisting of an arbitrary number of identical processes or components. The number of processes defines the size of the system. A parameterized system may be regarded as an infinite family of instances, namely one for each size. The aim is to perform a parameterized verification, i.e. to verify that behaviors produced by all instances, regardless of their size, comply with some safety or liveness property. In this work, we describe three approaches to parameterized verification. First, we extend the Regular Model Checking framework to systems where components are organized in tree-like structures. For such systems, we give a methodology for computing the set of reachable configurations (used to verify safety properties) and the transitive closure (used to verify liveness properties). Next, we introduce a methodology allowing the verification of safety properties for a large class of parameterized systems. We focus on systems where components are organized in linear arrays and manipulate variables or arrays of variables ranging over bounded or numerical domains. We perform backwards reachability analysis on a uniform over-approximation of the parameterized system at hand. Finally, we suggest a new approach that enables us to reduce the verification of termination under weak fairness conditions to a reachability analysis for systems with simple commutativity properties. The idea is that reachability calculations (associated with safety) are usually less expensive then termination (associated with liveness). This idea can also be used for other transition systems and not only those induced by parameterized systems.
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Bherer, Hans. "Controller Synthesis for Parameterized Discrete Event Systems". Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26696/26696.pdf.
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Les systèmes à événements discrets sont des systèmes dynamiques particuliers. Ils
changent d’état de fa¸con discrète et le terme événement est utilisé afin de représenter
l’occurrence de changements discontinus. Ces systèmes sont principalement construits
par l’homme et on les retrouve surtout dans les secteurs manufacturier, de la circu-
lation automobile, des bases de données et des protocoles de communication. Cette
thèse s’intéresse au contrôle des systèmes paramétrés à événements discrets où les
spécifications sont exprimées à l’aide de prédicats et satisfont une condition de similarité.
Des conditions sont données afin de déduire des propriétés, en observation partielle ou
totale, pour un système composé de n processus similaires à partir d’un système com-
posé de n0 processus, avec n ≥ n0. De plus, il est montré comment inférer des politiques
de contrôle en présence de relations d’interconnexion entre les processus. Cette étude
est principalement motivée par la faiblesse des méthodes actuelles de synthèse pour le
traitement des problèmes industriels de taille réelle.Discrete event systems are a special type of dynamic systems. The state of these systems changes only at discrete instants of time and the term event is used to represent the occurrence of discontinuous changes. These systems are mostly man-made and arise in the domains of manufacturing systems, traffic systems, database management systems and communication protocols. This thesis investigates the control of parameterized discrete event systems when specifications are given in terms of predicates and satisfy a similarity assumption. For systems consisting of similar processes under total or partial observation, conditions are given to deduce properties of a system of n processes from properties of a system of n0 processes, with n ≥ n0. Furthermore, it is shown how to infer a control policy for the former from the latter’s, while taking into account interconnections between processes. This study is motivated by a weakness in current synthesis methods that do not scale well to huge systems.
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Majumdar, Anirban. "Verification and synthesis of parameterized concurrent systems". Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG059.
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Cette thèse se situe au croisement de la vérification et de la synthèse des systèmes concurrents paramétrés. Le problème de la vérification de modèles paramétrés demande si un système satisfait une spécification donnée indépendamment du nombre de ses composants, alors que la synthèse vise la conception de protocoles pour ses composants afin que la spécification soit satisfaite.Nous étudions un modèle paramétré de réseaux où les processus sont distribués sur un graphe non orienté; ils exécutent le même protocole et communiquent par des diffusions sélectives de messages. Le problème de couverture demande si un état donné du protocole est peut être atteint. Nous montrons que pour les instances positives du problème de couverture, en supposant que la topologie de communication est reconfigurable, la taille et la longueur d'une exécution couvrante minimale sont bornées linéairement et quadratiquement, respectivement. Nous introduisons une sémantique de perte à l'envoi et montrons des bornes similaires pour la taille et la longueur d'une exécution couvrante.Les interactions entre différents agents peuvent être modélisées par des jeux. Nous introduisons et étudions deux cadres de ce que l'on appelle les jeux concurrents paramétrés, un modèle de jeux concurrents avec un nombre arbitraire d'agents. Tout d'abord, nous considérons le scénario où un joueur distingué Eve tente d'atteindre un objectif contre un nombre arbitraire d'adversaires, quelles que soient leurs stratégies. Nous prouvons que l'existence d'une stratégie gagnante pour Eve est décidable, et nous fournissons des bornes de complexité exactes pour ces jeux d'accessibilité. Deuxièmement, nous considérons un jeu de coalition où tous les joueurs essaient collectivement d'atteindre un objectif commun. Dans ce cadre, nous considérons des objectifs de sûreté et montrons que l'existence d'une stratégie de coalition gagnante est décidable, et nous établissons des bornes de complexité pour ce même problèmeThis thesis is at the crossroad of verification and synthesis of parameterized concurrent systems. The parameterized model checking problem asks whether a system satisfies a given specification independently of the number of its components, whereas synthesis requires an algorithmic design of protocols for its components so that the specification is satisfied.We study a parameterized model of networks where processes are distributed over an undirected graph, running the same broadcast protocol, and communicating via selective broadcasts of messages. The coverability problem asks whether a given state of the protocol is coverable. We show that for positive instances of the coverability problem in reconfigurable semantics, the size (cutoff) and the length (covering length) of a minimal covering execution is linearly and quadratically bounded, respectively. We introduce loss-on-broadcast semantics, and show similar bounds for the cutoff and the covering length.The interactions between agents can be modelled using games. We introduce and study two different settings of the so-called parameterized concurrent games, a model of concurrent games with arbitrarily many agents. First, we consider a scenario of a distinguished player Eve trying to achieve a goal against arbitrarily many opponents, irrespective of their strategies. We prove the existence of a winning strategy for Eve is decidable, and show tight complexity bounds for reachability objectives. Second, we consider a coalition game where all players collectively try to achieve a common goal. We consider safety objectives and show the existence of a winning coalition strategy is decidable, and prove complexity bounds for the same
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Haydar, May. "Parameterized events for designing real-time reactive systems". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ59324.pdf.
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Sävström, Tomas. "Small Model Theorems for Verification of Parameterized Systems". Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-244347.
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The world of software is increasing and the requirements on software systems are getting harder. To ensure that these requirements are fulfilled, we use program verification. The goal of verification is to prove that the system automatically fulfills its requirements. In this thesis, we will consider parameterized systems. A parameterized system is a system that contains an arbitrary number of components (processes) organized according to a particular pattern. Such systems are heavily used to implement mutual exclusion protocols [1,2]. In this thesis we will extend parameterized verification to handle variables over unbounded data domain. In fact, there is a large number of protocols (or programs) that manipulate variable over unbounded data domain. An example is the Bakery[2] protocol which uses integer variables to decide the order in which the processes are allowed to enter their critical section. In order to handle the unbounded data domain, we use abstract interpretation. The key idea is to abstract away the variable values and only keep their internal relationships. Finally, we have constructed a prototype in C and tested it again on a number of mutual exclusion protocol.
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Bond, Bradley N. (Bradley Neil). "Parameterized model order reduction for nonlinear dynamical systems". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37935.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 67-70).
The presence of several nonlinear analog circuits and Micro-Electro-Mechanical (MEM) components in modern mixed signal System-on-Chips (SoC) makes the fully automatic synthesis and optimization of such systems an extremely challenging task. The research presented in this thesis concerns the development of techniques for generating Parameterized Reduced Order Models (PROMs) of nonlinear dynamical systems. Such reduced order models could serve as a first step towards the automatic and accurate characterization of geometrically complex components and subcircuits, eventually enabling their synthesis and optimization. This work combines elements from a non-parameterized trajectory piecewise linear method for nonlinear systems with a moment matching paramneterized technique for linear systems. Exploiting these two methods one can create four different algorithms or generating PROMs of nonlinear systems. The algorithms were tested on three different systems: a MEM switch and two nonlinear analog circuits. All three examples contain distributed strong nonlinearities and possess dependence on several geometric parameters.
(cont.) Using the proposed algorithms, the local and global parameter-space accuracy of the reduced order models can be adjusted as desired. Models call be created which are extremely accurate over a narrow range of parameter values. as well as models which are less accurate locally but still provide adequate accuracy over a much wider range of parameter values.
by Bradley N. Bond.
S.M.
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Cao, Chengyu 1973. "Parameter estimation and control of nonlinearly parameterized systems". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30326.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references.
Parameter estimation in nonlinear systems is an important issue in measurement, diagnosis and modeling. The goal is to find a differentiator free on-line adaptive estimation algorithm which can estimate the internal unknown parameters of dynamic systems using its inputs and outputs. This thesis provides new algorithms for adaptive estimation and control of nonlinearly parameterized (NLP) systems. First, a Hierarchical Min-max algorithm is invented to estimate unknown parameters in NLP systems. To relax the strong condition needed for the convergence in Hierarchical Min-max algorithm, a new Polynomial Adaptive Estimator (PAE) is invented and the Nonlinearly Persistent Excitation Condition for NLP systems, which is no more restrictive than LPE for linear systems, is established for the first time. To reduce computation complexity of PAE, a Hierarchical PAE is proposed. Its performance in the presence of noise is evaluated and is shown to lead to bounded errors. A dead-zone based adaptive filter is also proposed and is shown to accurately estimate the unknown parameters under some conditions. Based on the adaptive estimation algorithms above, a Continuous Polynomial Adaptive Controller (CPAC) is developed and is shown to control systems with nonlinearities that have piece-wise linear parameterizations. Since large classes of nonlinear systems can be approximated by piece-wise linear functions through local linearization, it opens the door for adaptive control of general NLP systems. The robustness of CPAC under bounded output noise and disturbances is also established.
by Chengyu Cao.
Ph.D.
17
Jahundovics, Vladislavs. "Automatic Verification of Parameterized Systems by Over-Approximation". Licentiate thesis, Linköpings universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121776.
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This thesis presents a completely automatic verification framework to check safety properties of parameterized systems. A parameterized system is a family of finite state systems where every system consists of a finite number of processes running in parallel the same algorithm. All the systems in the family differ only in the number of the processes and, in general, the number of systems in a family may be unbounded. Examples of parameterized systems are communication protocols, mutual exclusion protocols, cache coherence protocols, distributed algorithms etc. Model-checking of finite state systems is a well-developed formal verification approach of proving properties of systems in an automatic way. However, it cannot be applied directly to parameterized systems because the unbounded number of systems in a family means an infinite state space. In this thesis we propose to abstract an original family of systems consisting of an unbounded number of processes into one consisting of a fixed number of processes. An abstracted system is considered to consist of k+1 components—k reference processes and their environment. The transition relation for the abstracted system is an over-approximation of the transition relation for the original system, therefore, a set of reachable states of the abstracted system is an over-approximation of the set of reachable states of the original one. A safety property is considered to be parameterized by a fixed number of processes whose relationship is in the center of attention in the property. Such processes serve as reference processes in the abstraction. We propose an encoding which allows to perform reachability analysis for an abstraction parameterized by the reference processes. We have successfully verified three classic parameterized systems with replicated processes by applying this method.
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BRADDE, TOMMASO. "Parameterized macromodeling of passive and active dynamical systems". Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2970988.
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Chan, Brendan K. "Hyperboloid-Parameterized Description of Diffusive Superconducting-Magnetic Hybrid Systems". Thesis, California State University, Long Beach, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10606400.
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We present a study of diffusive Josephson junctions made of two superconductors connected by a magnetic heterostructure. When the link is sufficiently thin, Cooper pairs can tunnel from one superconductor to the other, generating a Josephson current. Junctions with inhomogeneous magnetization are of particular interest because they may display triplet pair correlations with non-zero spin projection along the quantization axis. The generation of these correlations in the hybrid structure is studied by solving numerically the Usadel equations. In previous works, we have shown for example that the rotation of the magnetization can be used to tune the relative weight of the singlet and triplet pair correlations, thereby tuning the current. Here we present a novel approach to the numerical treatment of the Usadel equations, using a parameterization that takes automatically into account a required constraint of the model. The method significantly reduces the computational time, allowing us to calculate the Gor'kov functions self-consistently and extend the model to include the inverse proximity effect. We show results for SF and SFS systems with a helical magnetization profile for various twisting angles.
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KojiÄ, Aleksandar M. 1974. "Global parameter identification and control of nonlinearly parameterized systems". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/8330.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2002.Includes bibliographical references (leaves 109-114).
Nonlinearly parameterized (NLP) systems are ubiquitous in nature and many fields of science and engineering. Despite the wide and diverse range of applications, there exist relatively few results in control systems literature which exploit the structure of the nonlinear parameterization. A vast majority of presently applicable global control design approaches to systems with NLP, make use of either feedback-linearization, or assume linear parameterization, and ignore the specific structure of the nonlinear parameterization. While this type of approach may guarantee stability, it introduced three major drawbacks. First, they produce no additional information about the nonlinear parameters. Second, they may require large control authority and actuator bandwidth, which makes them unsuitable for some applications. Third, they may simply result in unacceptably poor performance. All of these inadequacies are amplified further when parametric uncertainties are present. What is necessary is a systematic adaptive approach to identification and control of such systems that explicitly accommodates the presence of nonlinear parameters that may not be known precisely. This thesis presents results in both adaptive identification and control of NLP systems. An adaptive controller is presented for NLP systems with a triangular structure. The presence of the triangular structure together with nonlinear parameterization makes standard methods such as back-stepping, and variable structure control inapplicable. A concept of bounding functions is combined with min-max adaptation strategies and recursive error formulation to result in a globally stabilizing controller.
(cont.) A large class of nonlinear systems including cascaded LNL (linear-nonlinear-linear) systems are shown to be controllable using this approach. In the context of parameter identification, results are derived for two classes of NLP systems. The first concerns systems with convex/concave parameterization, where min-max algorithms are essential for global stability. Stronger conditions of persistent excitation are shown to be necessary to overcome the presence of multiple equilibrium points which are introduced due to the stabilization aspects of the min-max algorithms. These conditions imply that the min-max estimator must periodically employ the local gradient information in order to guarantee parameter convergence. The second class of NLP systems considered in this concerns monotonically parameterized systems, of which neural networks are a specific example. It is shown that a simple algorithm based on local gradient information suffices for parameter identification. Conditions on the external input under which the parameter estimates converge to the desired set starting from arbitrary values are derived. The proof makes direct use of the monotonicity in the parameters, which in turn allows local gradients to be self-similar and therefore introduces a desirable invariance property. By suitably exploiting this invariance property and defining a sequence of distance metrics, global convergence is proved. Such a proof of global convergence is in contrast to most other existing results in the area of nonlinear parameterization, in general, and neural networks in particular.
by Aleksandar M. KojiÄ.
Ph.D.
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Sakr, Mouhammad [Verfasser]. "Parameterized verification and repair of concurrent systems / Mouhammad Sakr". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2021. http://d-nb.info/1236571320/34.
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Baur, Ulrike, Christopher Beattie, Peter Benner e Serkan Gugercin. "Interpolatory Projection Methods for Parameterized Model Reduction". Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000011.
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We provide a unifying projection-based framework for structure-preserving interpolatory model reduction of parameterized linear dynamical systems, i.e., systems having a structured dependence on parameters that we wish to retain in the reduced-order model. The parameter dependence may be linear or nonlinear and is retained in the reduced-order model. Moreover, we are able to give conditions under which the gradient and Hessian of the system response with respect to the system parameters is matched in the reduced-order model. We provide a systematic approach built on established interpolatory $\mathcal{H}_2$ optimal model reduction methods that will produce parameterized reduced-order models having high fidelity throughout a parameter range of interest. For single input/single output systems with parameters in the input/output maps, we provide reduced-order models that are \emph{optimal} with respect to an $\mathcal{H}_2\otimes\mathcal{L}_2$ joint error measure. The capabilities of these approaches are illustrated by several numerical examples from technical applications.
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Saksena, Mayank. "Verifying Absence of ∞ Loops in Parameterized Protocols". Doctoral thesis, Uppsala University, Department of Information Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8605.
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The complex behavior of computer systems offers many challenges for formal verification. The analysis quickly becomes difficult as the number of participating processes increases.
A parameterized system is a family of systems parameterized on a number n, typically representing the number of participating processes. The uniform verification problem — to check whether a property holds for each instance — is an infinite-state problem. The automated analysis of parameterized and infinite-state systems has been the subject of research over the last 15–20 years. Much of the work has focused on safety properties. Progress in verification of liveness properties has been slow, as it is more difficult in general.
In this thesis, we consider verification of parameterized and infinite-state systems, with an emphasis on liveness, in the verification framework called regular model checking (RMC). In RMC, states are represented as words, sets of states as regular expressions, and the transition relation as a regular relation.
We extend the automata-theoretic approach to RMC. We define a specification logic sufficiently strong to specify systems representable using RMC, and linear temporal logic properties of such systems, and provide an automatic translation from a specification into an analyzable model.
We develop acceleration techniques for RMC which allow more uniform and automatic verification than before, with greater power. Using these techniques, we succeed to verify safety and liveness properties of parameterized protocols from the literature.
We present a novel reachability based verification method for verification of liveness, in a general setting. We implement the method for RMC, with promising results.
Finally, we develop a framework for the verification of dynamic networks based on graph transformation, which generalizes the systems representable in RMC. In this framework we verify the latest version of the DYMO routing protocol, currently being considered for standardization by the IETF.
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Deneux, Johann. "Verification of Parameterized and Timed Systems : Undecidability Results and Efficient Methods". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6891.
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Bui-Thanh, Tan. "Model-constrained optimization methods for reduction of parameterized large-scale systems". Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40305.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 143-158).
Most model reduction techniques employ a projection framework that utilizes a reduced-space basis. The basis is usually formed as the span of a set of solutions of the large-scale system, which are computed for selected values (samples) of input parameters and forcing inputs. In existing model reduction techniques, choosing where and how many samples to generate has been, in general, an ad-hoc process. A key challenge is therefore how to systematically sample the input space, which is of high dimension for many applications of interest. This thesis proposes and analyzes a model-constrained greedy-based adaptive sampling approach in which the parametric input sampling problem is formulated as an optimization problem that targets an error estimation of reduced model output prediction. The method solves the optimization problem to find a locally-optimal point in parameter space where the error estimator is largest, updates the reduced basis with information at this optimal sample location, forms a new reduced model, and repeats the process. Therefore, we use a systematic, adaptive error metric based on the ability of the reduced-order model to capture the outputs of interest in order to choose the snapshot locations that are locally the worst case scenarios.
(cont.) The state-of-the-art subspace trust-region interior-reflective inexact Newton conjugate-gradient optimization solver is employed to solve the resulting greedy partial differential equation constrained optimization problem, giving a reduction methodology that is efficient for large-scale systems and scales well to high-dimensional input spaces. The model-constrained adaptive sampling approach is applied to a steady thermal fin optimal design problem and to probabilistic analysis of geometric mistuning in turbomachinery. The method leads to reduced models that accurately represent the full large-scale systems over a wide range of parameter values in parametric spaces up to dimension 21.
by Tan Bui-Thanh.
Ph.D.
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Haziza, Frédéric. "Few is Just Enough! : Small Model Theorem for Parameterized Verification and Shape Analysis". Doctoral thesis, Uppsala universitet, Avdelningen för datorteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-264171.
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This doctoral thesis considers the automatic verification of parameterized systems, i.e. systems with an arbitrary number of communicating components, such as mutual exclusion protocols, cache coherence protocols or heap manipulating programs. The components may be organized in various topologies such as words, multisets, rings, or trees. The task is to show correctness regardless of the size of the system and we consider two methods to prove safety:(i) a backward reachability analysis, using the well-quasi ordered framework and monotonic abstraction, and (ii) a forward analysis which only needs to inspect a small number of components in order to show correctness of the whole system. The latter relies on an abstraction function that views the system from the perspective of a fixed number of components. The abstraction is used during the verification procedure in order to dynamically detect cut-off points beyond which the search of the state-space need not continue. Our experimentation on a variety of benchmarks demonstrate that the method is highly efficient and that it works well even for classes of systems with undecidable property. It has been, for example, successfully applied to verify a fine-grained model of Szymanski's mutual exclusion protocol. Finally, we applied the methods to solve the complex problem of verifying highly concurrent data-structures, in a challenging setting: We do not a priori bound the number of threads, the size of the data-structure, the domain of the data to store nor do we require the presence of a garbage collector. We successfully verified the concurrent Treiber's stack and Michael & Scott's queue, in the aforementioned setting. To the best of our knowledge, these verification problems have been considered challenging in the parameterized verification community and could not be carried out automatically by other existing methods.
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DIAZ, RUBEN GOMEZ. "A SYSTEM FOR GENERATION OF PARAMETERIZED MODELS FOR VESSELS DESIGN". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14888@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOEste trabalho situa-se numa das linhas de pesquisa da PUC-Rio de projeto de unidades flutuantes tais como, navios e plataformas semi-submersíveis. Nesta linha de pesquisa estão sendo desenvolvidos os programas gráficos MG (Mesh Generator) e o Sstab. O primeiro programa é um modelador geométrico por meio de seções transversais e gerador de malhas para modelos de estruturas flutuantes. O segundo programa é utilizado para a análise de estabilidade estática dos modelos gerados pelo MG. Este trabalho propõe um ambiente integrado de modelagem e de análise estática e dinâmica de estruturas flutuantes. O principal diferencial deste ambiente está no fato de possibilitar a geração automática de variantes de um determinado modelo padrão, a fim de atingir uma configuração desejada, seja no aspecto geométrico ou com relação a sua estabilidade estática. Este ambiente faz uso da linguagem Lua e é possível definir variáveis globais para serem utilizadas como parâmetros de modelagem que extraem, ou modificam, dados como comprimento, largura, altura etc. É possível parametrizar um modelo qualquer, em função de variáveis escolhidas pelo usuário, o que possibilita uma modelagem automática, com a variação de alguns destes parâmetros. Foram ainda desenvolvidas algumas ferramentas auxiliares que facilitam a modelagem de uma estrutura flutuante. Estas ferramentas verificam a consistência topológica de uma malha, gerar uma subdivisão gradativa das curvas cortadas e simplificar as novas malhas geradas. É possível também detectar se o modelo possui simetria num determinado plano e realizar, de forma automática, cortes do modelo final para diferentes calados.
This work is related to the PUC-Rio research area of vessel´s designs such as ships and semi-sub platforms. In this research area two softwares have been developed: MG and Sstab. The first is a geometric modeler based on cross sections and also on a mesh generator; the second is a software for the analysis of static and dynamic stability of MG models. This work proposes an integrated environment for modeling, and static and dynamic analysis of vessels. The main advantage of the proposed environment is that it is possible to obtain automatically variants of a specific model in order to achieve a desired configuration, not only in relation to geometry but also concerning the static stability aspect. This environment uses the Lua programming language and it is possible to define global variables to be used as parameters which retrieve or modify modeling values such as length, width, height, and so on. Any model can be parameterized, as a function of user chosen variables, which allows an automatic modeling with the variation of those parameters. There has been also developed some auxiliary tools which help the modeling of floating structures. Those tools verify the topological consistency of a mesh, generate a gradual subdivision of intersected curves and simplify the new generated meshes. They are also able to detect if the model has symmetry in relation to a certain plane, and sections can be automatically obtained according to different draughts.
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Röckl, Christine. "On the mechanized validation of infinite-state and parameterized reactive and mobile systems". [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962067180.
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Göthel, Thomas [Verfasser], e Sabine [Akademischer Betreuer] Glesner. "Mechanical Verification of Parameterized Real-Time Systems / Thomas Göthel. Betreuer: Sabine Glesner". Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1023762234/34.
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Rubattu, Claudio. "Response time analysis of parameterized dataflow applications on heterogeneous SW/HW systems". Thesis, Rennes, INSA, 2020. http://www.theses.fr/2020ISAR0005.
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Les fortes contraintes de réactivité et de consommation énergétique des systèmes embarqués et cyber-physiques nécessitent l’utilisation croissante de systèmes de calculs parallèles et fortement hétérogènes. La nature de ces systèmes parallèles implique une énorme complexité dans la compréhension et la prévision des performances en termes de temps de réponse. En effet, le temps de réponse dépend de nombreux facteurs associés aux caractéristiques à la fois de la fonctionnalité implémentée et de l’architecture cible. Les méthodes d’optimisation système actuelles dérivent le temps de réponse du système en examinant les opérations requises par chaque tâche, tant pour le traitement que pour l’accès aux ressources partagées. Cette procédure est souvent suivie par l’ajout ou l’élimination des interférences potentielles dues à la concurrence entre tâches. Cependant, de telles approches nécessitent une connaissance avancée des détails du logiciel et du matériel, rarement disponible en pratique lors du dimensionnement du système. Cette thèse propose une stratégie alternative "top-down" visant à étendre les cas dans lesquels le temps de réponse matériel et logiciel peut être analysé et prédit. La stratégie proposée s’appuie sur des représentations d’applications par des modèles flux de données et se concentre sur l’estimation du temps de réponse d’applications reconfigurables exécutées par des unités de calcul à la fois générales et spécialiséesIn contexts such as embedded and cyber-physical systems, the design of a desired functionality under constraints increasingly requires a parallel execution of different tasks on heterogeneous architectures. The nature of such parallel systems implies a huge complexity in understanding and predicting performance in terms of response time. Indeed, response time depends on many factors associated with the characteristics of both the functionality and the target architecture. State-of-the art strategies derive response time by examining the operations required by each task for both processing and accessing shared resources. This procedure is often followed by the addition or elimination of potential interferences due to task concurrency. However, such approaches require an advanced knowledge of the software and hardware details, rarely available in practice. This thesis provides an alternative "topdown" strategy aimed at extending the cases in which hardware and software response times can be analyzed and predicted. The proposed strategy leverages on dataflow-based application representations and focuses on the response time estimation of reconfigurable applications mapped on both general-purpose and specialized processing elements
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Arslan, Ali Erkin. "Range Parameterized Bearings-only Tracking Using Particle Filter". Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614888/index.pdf.
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In this study, accurate target tracking for bearings-only tracking problem is investigated. A new tracking filter for this nonlinear problem is designed where both range parameterization and Rao-Blackwellized (marginalized) particle filtering techniques are used in a Gaussian mixture formulation to track both constant velocity and maneuvering targets. The idea of using target turn rate in the state equation in such a way that marginalization is possible is elaborated. Addition to nonlinear nature, unobservability is a major problem of bearings-only tracking. Observer trajectory generation to increase the observability of the bearings-only tracking problem is studied. Novel formulation of observability measures based on mutual information between the state and the measurement sequences are derived for the problem. These measures are used as objective functions to improve observability. Based on the results obtained better understanding of the required observer trajectory for accurate bearings-only target tracking is developed.
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Hover, Franz S. "Deeply-towed underwater vehicle systems : a verified analytical procedure for creating parameterized dynamic models". Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14005.
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Frechina, Navarro Francisco. "A Rewriting-based, Parameterized Exploration Scheme for the Dynamic Analysis of Complex Software Systems". Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/44234.
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Los sistemas software actuales son artefactos complejos cuyo comportamiento es a menudo extremadamente difícil de entender. Este hecho ha llevado al desarrollo de metodologías formales muy sofisticadas para el análisis, comprensión y depuración de programas.
El análisis de trazas de ejecución consiste en la búsqueda dinámica de contenidos específicos dentro de las trazas de ejecución de un cierto programa. La búsqueda puede llevarse a cabo hacia adelante o hacia atrás. Si bien el análisis hacia adelante se traduce en una forma de análisis de impacto que identifica el alcance y las posibles consecuencias de los cambios en la entrada del programa, el análisis hacia atrás permite llevar a cabo un rastreo de la procedencia; es decir, muestra como (partes de) la salida del programa depende de (partes de) su entrada y ayuda a estimar qué dato de la entrada es necesario modificar para llevar a cabo un cambio en el resultado.
En esta tesis se investiga una serie de metodologías de análisis de trazas que son especialmente adecuadas para el análisis de trazas de ejecución largas y complejas en la lógica de reescritura, que es un marco lógico y semántico especialmente adecuado para la formalización de sistemas altamente concurrentes.
La primera parte de la tesis se centra en desarrollar una técnica de análisis de trazas hacia atrás que alcanza enormes reducciones en el tamaño de la traza. Esta metodología se basa en la fragmentación incremental y favorece un mejor análisis y depuración ya que la mayoría de las inspecciones, tediosas e irrelevantes, que se realizan rutinariamente en el diagnostico y la localización de errores se pueden eliminar de forma automática. Esta técnica se ilustra por medio de varios ejemplos que ejecutamos mediante el sistema iJulienne, una herramienta interactiva de fragmentación que hemos desarrollado y que implementa la técnica de análisis de trazas hacia atrás. En la segunda parte de la tesis se formaliza un sistema paramétrico, flexible y dinámico, para la exploración de computaciones en la lógica de reescritura. El esquema implementa un algoritmo de animación gen érico que permite la ejecución indeterminista de una teoría de reescritura condicional dada y que puede ser objeto de seguimiento mediante el uso de diferentes modalidades, incluyendo una ejecución gradual paso a paso y una fragmentación automática hacia adelante y/o hacia atrás, lo que reduce drásticamente el tamaño y la complejidad de las trazas bajo inspección y permite a los usuarios evaluar de forma aislada los efectos de una declaración o instrucción dada, el seguimiento de los efectos del cambio de la entrada, y obtener información sobre el comportamiento del programa (o mala conducta del mismo). Por otra parte, la fragmentación de la traza de ejecución puede identificar nuevas oportunidades de optimización del programa. Con esta metodología, un analista puede navegar, fragmentar, filtrar o buscar en la traza durante la ejecución del programa. El marco de análisis de trazas gen érico se ha implementado en el sistema Anima y describimos una profunda evaluación experimental de este que demuestra la utilidad del enfoque propuesto.Frechina Navarro, F. (2014). A Rewriting-based, Parameterized Exploration Scheme for the Dynamic Analysis of Complex Software Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/44234
TESIS
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Murali, madhavan rathai Karthik. "Synthesis and real-time implementation of parameterized NMPC schemes for automotive semi-active suspension systems". Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT052.
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Cette thèse traite de la synthèse et de la mise en œuvre en temps réel (RT) de schémas de contrôle prédictif non linéaire paramétré (pNMPC) pour les systèmes de suspension semi-active des automobiles. Le schéma pNMPC est basé sur une technique d'optimisation par simulation en boîte noire. Le point essentiel de la méthode est de paramétrer finement le profil d'entrée et de simuler le système pour chaque entrée paramétrée et d'obtenir la valeur approximative de l'objectif et de la violation des contraintes pour le problème pNMPC. Avec les résultats obtenus de la simulation, l'entrée admissible (si elle existe) ayant la valeur objective minimale ou, à défaut, la valeur de violation de contrainte la plus faible est sélectionnée et injectée dans le système et ceci est répété indéfiniment à chaque période de décision. La méthode a été validée expérimentalement sur dSPACE MicroAutoBoX II (MABXII) et les résultats montrent de bonnes performances de l'approche proposée. La méthode pNMPC a également été étendue à une méthode pNMPC parallélisée et la méthode proposée a été mise en œuvre pour le contrôle du système de suspension semi-active d'un demi-véhicule. Cette méthode a été mise en œuvre grâce à des unités de traitement graphique (GPU) qui servent de plate-forme modèle pour la mise en œuvre d'algorithmes parallèles par le biais de ses processeurs multi-cœurs. De plus, une version stochastique de la méthode pNMPC parallélisée est proposée sous le nom de schéma pNMPC à Scénario-Stochastique (SS-pNMPC). Cette méthode a été mise en œuvre et testée sur plusieurs cartes NVIDIA embarquées pour valider la faisabilité de la méthode proposée pour le contrôle du système de suspension semi-active d'un demi-véhicule. En général, les schémas pNMPC parallélisés offrent de bonnes performances et se prêtent bien à un large espace de paramétrage en entrée. Enfin, la thèse propose un outil logiciel appelé "pNMPC - A code generation software tool for implementation of derivative free pNMPC scheme for embedded control systems". L'outil logiciel de génération de code (S/W) a été programmé en C/C++ et propose également une interface avec MATLAB/Simulink. Le logiciel de génération de code a été testé pour divers exemples, tant en simulation que sur du matériel embarqué en temps réel (MABXII), et les résultats semblent prometteurs et viables pour la mise en œuvre de la RT pour des applications réelles. L'outil de génération de code S/W comprend également une fonction de génération de code GPU pour une mise en œuvre parallèle. Pour conclure, la thèse a été menée dans le cadre du projet EMPHYSIS et les objectifs du projet s'alignent sur cette thèse et les méthodes pNMPC proposées sont compatibles avec la norme eFMIThis thesis discusses the synthesis and real-time (RT) implementation of parameterized Nonlinear Model Predictive Control (pNMPC) schemes for automotive semi-active suspension systems. The pNMPC scheme uses a black-box simulation-based optimization method. The crux of the method is to finitely parameterize the input profile and simulate the system for each parameterized input and obtain the approximate objective and constraint violation value for the pNMPC problem. With the obtained results from the simulation, the input with minimum objective value or the least constraint violation value is selected and injected into the system and this is repeated in a receding horizon fashion. The method was experimentally validated on dSPACE MicroAutoBoX II (MABXII) and the results display good performance of the proposed approach. The pNMPC method was also augmented to parallelized pNMPC and the proposed method was implemented for control of semi-active suspension system for a half car vehicle. This method was implemented by virtue of Graphic Processing Units (GPUs) which serves as a paragon platform for implementation of parallel algorithms through its multi-core processors. Also, a stochastic version of the parallelized pNMPC method is proposed which is termed as Scenario-Stochastic pNMPC (SS-pNMPC) scheme and the method was implemented and tested on several NVIDIA embedded boards to verify and validate the RT feasibility of the proposed method for control of semi-active suspension system for a half car vehicle. In general, the parallelized pNMPC schemes provide good performance and also, fares well for large input parameterization space. Finally, the thesis proposes a software tool termed “pNMPC – A code generation software tool for implementation of derivative free pNMPC scheme for embedded control systems”. The code generation software (S/W) tool was programmed in C/C++ and also, provides interface to MATLAB/Simulink. The S/W tested for variety of examples both in simulation as well as on RT embedded hardware (MABXII) and the results looks promising and viable for RT implementation for real world applications. The code generation S/W tool also includes GPU code generation feature for parallel implementation. To conclude, the thesis was conducted under the purview of the EMPHYSIS project and the goals of the project align with this thesis and the proposed pNMPC methods are amenable with eFMI standard
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Lacirignola, Martino. "Life cycle assessment of enhanced geothermal systems : from specific case studies to generic parameterized models". Thesis, Paris, CNAM, 2017. http://www.theses.fr/2017CNAM1095/document.
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Cette recherche vise à étudier les impacts environnementaux d'une technologie émergente de production d’électricité basée sur une source renouvelable, les systèmes géothermiques stimulés (EGS), par l’analyse de leur cycle de vie (ACV).Après avoir analysé plusieurs études de cas, nous avons développé un modèle ACV paramétré capable de caractériser les performances environnementales de la filière EGS. Nos résultats montrent que les émissions de gaz à effet de serre des EGS sur leur cycle de vie sont bien inférieures à celles des centrales utilisant des combustibles fossiles.Dans un deuxième temps, nous avons mis au point un cadre méthodologique pour appliquer l'analyse de sensibilité globale (GSA) à l’ACV des technologies émergentes comme les EGS, prenant en compte les incertitudes élevées liées à leur caractère innovant. Nous avons appliqué notre nouvelle approche GSA pour développer un modèle ACV simplifié, à destination des décideurs, permettant une estimation rapide des impacts des EGS à partir de seulement cinq paramètres clefs: capacité installée, profondeur de forage, nombre de puits, débit géothermal et durée de vie.L'approche méthodologique développée dans cette thèse est applicable à d'autres technologies et ouvre de larges perspectives de recherche dans le domaine de l'évaluation environnementaleThis thesis investigates the environmental impacts of an emerging renewable energy technology, the enhanced geothermal systems (EGS), using a life cycle assessment (LCA) approach.Following the analysis of several EGS case studies, we developed a parameterized LCA model able to provide a global overview of the life cycle impacts of the EGS technology. The greenhouse gas emissions of EGS are found comparable with other renewable energy systems and far better than those of power plants based on fossil fuels.In a second stage, we developed a methodological framework for the application of global sensitivity analysis (GSA) to the LCA of emerging technologies like the EGS, taking into account the high uncertainties related to their description. We applied our new GSA approach to generate a simplified LCA model, aimed at decision makers, allowing a rapid estimation of the life cycle impacts of EGS from only five key parameters: installed capacity, drilling depth, number of wells, flow rate and lifetime.The methodological approach developed in this thesis is applicable to other technologies and opens large research perspectives in the field of environmental assessment
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Andung, Muntaha Muhamad. "Non-intrusive Logging and Monitoring System of a Parameterized Hardware-in-the-loop Real-Time Simulator". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254655.
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Electronic Control Unit (ECU) is a crucial component in today’s vehicle. In a complete vehicle, there are many ECUs installed. Each of these controls a single function of the vehicle. During the development cycle of an ECU, its functionality needs to be validated against the requirement specification. The Hardware-in-the-loop (HIL) method is commonly used to do this by testing the ECU in a virtual representation of its controlled system. One crucial part of the HIL testing method is an intermediary component that acts as a bridge between the simulation computer and the ECU under test. This component runs a parameterized real-time system that translates messages from the simulation computer to the ECU under test and vice versa. It has a strict real-time requirement for each of its tasks to complete.A logging and monitoring system is needed to ensure that the intermediary component is functioning correctly. This functionality is implemented in the form of low priority additional tasks that run concurrently with the high priority message translation tasks. The implementation of these tasks, alongside with a distributed system to support the logging and monitoring functionality, is presented in this thesis work.Several execution time measurements are carried out to get the information on how the parameters of a task affect its execution time. Then, the linear regression analysis is used to model the execution time estimation of the parameterized tasks. Finally, the time demand analysis is utilized to provide a guarantee that the system is schedulable.Elektronisk styrenhet (ECU) är en viktig del i dagens fordon. I ett komplett fordon finns det många ECU installerade. Var och en av dessa kontrollerar en enda funktion hos fordonet. Under en utvecklingscykel för en ecu måste dess funktionalitet valideras mot kravspecifikationen. HIL-metoden (Hardware-in-the-loop) används vanligtvis för att göra detta genom att testa ECU i en virtuell representation av sitt styrda system. En viktig del av HIL-testmetoden är en mellanliggande komponent som fungerar som en bro mellan simuleringsdatorn och den ecu som testas. Denna komponent driver ett parametrerat realtidssystem som översätter meddelanden från simuleringsdatorn till ECU som testas och vice versa. Det har en strikt realtidskrav för att alla uppgifter ska kunna slutföras.Ett loggnings och övervakningssystem behövs för att den mellanliggande komponenten ska fungera korrekt. Denna funktionalitet är implementerad i form av extraordinära uppgifter med låg prioritet som körs samtidigt med de högsta prioritetsuppgifterna för översättningstjänster. Genomförandet av dessa uppgifter, tillsammans med ett distribuerat system för att stödja loggnings och övervakningsfunktionaliteten, presenteras i detta avhandlingararbete.Flera utförandetidsmätningar utförs för att få information om hur parametrarna för en uppgift påverkar dess körtid. Därefter används den linjära regressionsanalysen för att modellera exekveringstidestimeringen av de parametrerade uppgifterna. Slutligen används tidsanalysanalysen för att garantera att systemet är schemaläggbart.
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Stavrakakis, Kynthia Katherina [Verfasser], Thomas [Akademischer Betreuer] Weiland e Romanus [Akademischer Betreuer] Dyczij-Edlinger. "Model Order Reduction Methods for Parameterized Systems in Electromagnetic Field Simulations / Kynthia Katherina Stavrakakis. Betreuer: Thomas Weiland ; Romanus Dyczij-Edlinger". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2012. http://d-nb.info/110611650X/34.
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Farough, Aida. "A Parameterized Approach to Partitioning Between Focused and Diffuse Heat Output and Modeling Hydrothermal Recharge at The East Pacific Rise 9°50´N". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/78062.
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Ever since the discovery of seafloor hydrothermal systems at mid ocean ridges, scientists have been trying to understand the complex dynamic processes by which thermal energy is transported advectively by chemically reactive aqueous fluids from Earth's interior to the surface. Hydrothermal systems are generally assumed to consist of a heat source and a fluid circulation system. Understanding the interconnected physical, chemical, biological, and geological processes at oceanic spreading centers is important because these processes affect the global energy and biogeochemical budgets of the Earth system.
Despite two decades of focused study of hydrothermal systems, several key questions remain concerning the behavior and evolution of hydrothermal vent systems. Among these are: (a) the partitioning of heat transport between focused and diffuse flow, and (b) the spatial extent and distribution of hydrothermal recharge. These are the main topics of investigation in this thesis.
To address these issues, I first use a single-pass modeling approach using a variety of observational data in a simple parametric scale analysis of a hydrothermal vent field to determine fundamental parameters associated with the circulation and magmatic heat transfer for a number of seafloor hydrothermal systems for which the constraining data are available. To investigate the partitioning of heat flux between focused high temperature and diffuse flow I extend the one-limb single pass model to incorporate two single-pass limbs to represent deep and shallow circulation pathways. As a result, I find that 90% of the heat output is from high temperature fluid circulating in the deep limb even though much of the heat loss appears at the seafloor as low-temperature diffuse flow.
Next, I use the parametric description of hydrothermal circulation to investigate hydrothermal recharge at the East Pacific Rise 9°50′ N hydrothermal site. Using a 1-D model of recharge through an area of 10⁵ m² elucidated by microseismicity in the oceanic crust I find that anhydrite precipitation is likely to result in rapid sealing of pore space in the recharge zone. This would lead to rapid decay of hydrothermal venting, which is contrary to observations. Then I consider two-dimensional numerical models of hydrothermal circulation in a porous box heated from below. The preliminary results of these models suggests that the anhydrite precipitation zone will be more diffuse, but additional work is needed to test whether anhydrite precipitation will seal the pore space.Master of Science
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Kaiser, Alexander. "Monotonicity in shared-memory program verification". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:1d16b4b5-524a-40db-b7bf-062374f8679c.
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Predicate abstraction is a key enabling technology for applying model checkers to programs written in mainstream languages. It has been used very successfully for debugging sequential system-level C code. Although model checking was originally designed for analysing concurrent systems, there is little evidence of fruitful applications of predicate abstraction to shared-variable concurrent software. The goal of the present thesis is to close this gap. We propose an algorithmic solution implementing predicate abstraction that targets safety properties in non-recursive programs executed by an unbounded number of threads, which communicate via shared memory or higher-level mechanisms, such as mutexes and broadcasts. As system-level code makes frequent use of such primitives, their correct usage is critical to ensure reliability. Monotonicity - the property that thread actions remain executable when other threads are added to the current global state - is a natural and common feature of human-written concurrent software. It is also useful: if every thread’s memory is finite, monotonicity often guarantees the decidability of safety properties even when the number of running threads is unspecified. In this thesis, we show that the process of obtaining finite-data thread abstrac tions for model checking is not always compatible with monotonicity. Predicate-abstracting certain mainstream asynchronous software such as the ticket busy-wait lock algorithm results in non-monotone multi-threaded Boolean programs, despite the monotonicity of the input program: the monotonicity is lost in the abstraction. As a result, the unbounded thread Boolean programs do not give rise to well quasi-ordered systems [1], for which sound and complete safety checking algorithms are available. In fact, safety checking turns out to be undecidable for the obtained class of abstract programs, despite the finiteness of the individual threads’ state spaces. Our solution is to restore the monotonicity in the abstract program, using an inexpensive closure operator that precisely preserves all safety properties from the (non-monotone) abstract program without the closure. As a second contribution, we present a novel, sound and complete, yet empirically much improved algorithm for verifying abstractions, applicable to general well quasi-ordered systems. Our approach is to gradually widen the set of safety queries during the search by program states that involve fewer threads and are thus easier to decide, and are likely to finalise the decision on earlier queries. To counter the negative impact of "bad guesses", i.e. program states that turn out feasible, the search is supported by a parallel engine that generates such states; these are never selected for widening. We present an implementation of our techniques and extensive experiments on multi-threaded C programs, including device driver code from FreeBSD and Solaris. The experiments demonstrate that by exploiting monotonicity, model checking techniques - enabled by predicate abstraction - scale to realistic programs even of a few thousands of multi-threaded C code lines.
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Korneva, Alexandrina. "The Cubicle Fuzzy Loop : A Testing Framework for Cubicle". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASG095.
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L'objectif de cette thèse est d'intégrer une technique de test dans le model checker Cubicle. Pour cela, nous avons étendu Cubicle avec une boucle de Fuzzing (appelée Cubicle Fuzzy Loop - CFL). Cette nouvelle fonctionnalité remplit deux fonctions principales.Tout d'abord, elle sert d'oracle pour l'algorithme de génération d'invariants de Cubicle. Ce dernier, basé sur une exploration en avant de l'ensemble des états atteignables, était fortement limité par ses heuristiques lorsqu'elles sont appliquées à des modèles fortementconcurrents. CFL apporte une nouvelle manière plus efficace d'explorer ces modèles, en particulier il permet de visiter beaucoup plus d'états pertinents.Son deuxième objectif est de détecter rapidement et efficacement les problèmes et les vulnérabilités dans les modèles de toutes tailles, ainsi que de capturer les deadlocks.L'intégration de CFL nous a également permis d'augmenter l'expressivité du langage d'entrée de Cubicle, avec l'inclusion de nouvelles primitives pour manipuler des threads (verrous, sémaphores, etc.).Enfin, nous avons construit un cadre de test autour de Cubicle et de CFL avec un interpréteur interactif, utile pour le débogage, le prototypage et l'exécution pas à pas des modèles. Ce nouveau système a été appliqué avec succès sur une étude de cas d'un algorithme deconsensus distribué pour blockchainsThe goal of this thesis is to integrate a testing technique into the Cubicle model checker. To do this, we extended Cubicle with a Fuzzing loop (called the Cubicle Fuzzy Loop - CFL). This new feature serves two primary purposes.Firstly, it acts as an oracle for Cubicle's invariant generation algorithm. The existing algorithm, which is based on a forward exploration of reachable states, was significantly limited by its heuristics when applied to highly concurrent models. CFL introduces amore efficient way to explore these models, visiting a larger number of relevant states.Its second objective is to quickly and efficiently detect issues and vulnerabilities in models of all sizes, as well as detect deadlocks.The integration of CFL has also enabled us to enhance the expressiveness of Cubicle's input language, including new primitives for manipulating threads (locks, semaphores, etc.).Lastly, we built a testing framework around Cubicle and CFL with an interactive interpreter, which is useful for debugging, prototyping, and step-by-step execution of models. This new system has been successfully applied in a case study of a distributed consensus algorithm for blockchains
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Mebsout, Alain. "Inférence d'invariants pour le model checking de systèmes paramétrés". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112188/document.
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Cette thèse aborde le problème de la vérification automatique de systèmesparamétrés complexes. Cette approche est importante car elle permet de garantircertaines propriétés sans connaître a priori le nombre de composants dusystème. On s'intéresse en particulier à la sûreté de ces systèmes et on traitele côté paramétré du problème avec des méthodes symboliques. Ces travauxs'inscrivent dans le cadre théorique du model checking modulo théories et ontdonné lieu à un nouveau model checker : Cubicle.Une des contributions principale de cette thèse est une nouvelle technique pourinférer des invariants de manière automatique. Le processus de générationd'invariants est intégré à l'algorithme de model checking et permet de vérifieren pratique des systèmes hors de portée des approches symboliquestraditionnelles. Une des applications principales de cet algorithme estl’analyse de sûreté paramétrée de protocoles de cohérence de cache de tailleindustrielle.Enfin, pour répondre au problème de la confiance placée dans le model checker,on présente deux techniques de certification de notre outil Cubicle utilisantla plate-forme Why3. La première consiste à générer des certificats dont lavalidité est évaluée de manière indépendante tandis que la seconde est uneapproche par vérification déductive du cœur de CubicleThis thesis tackles the problem of automatically verifying complexparameterized systems. This approach is important because it can guarantee thatsome properties hold without knowing a priori the number of components in thesystem. We focus in particular on the safety of such systems and we handle theparameterized aspect with symbolic methods. This work is set in the theoreticalframework of the model checking modulo theories and resulted in a new modelchecker: Cubicle.One of the main contribution of this thesis is a novel technique forautomatically inferring invariants. The process of invariant generation isintegrated with the model checking algorithm and allows the verification inpractice of systems which are out of reach for traditional symbolicapproaches. One successful application of this algorithm is the safety analysisof industrial size parameterized cache coherence protocols.Finally, to address the problem of trusting the answer given by the modelchecker, we present two techniques for certifying our tool Cubicle based on theframework Why3. The first consists in producing certificates whose validity canbe assessed independently while the second is an approach by deductiveverification of the heart of Cubicle
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Pham, Thi Ngoc Diem. "Spécification et conception de services d'analyse de l'utilisation d'un environnement informatique pour l’apprentissage humain". Thesis, Le Mans, 2011. http://www.theses.fr/2011LEMA1015/document.
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Notre travail de recherche s’inscrit dans le cadre du projet de recherche REDiM (Réingénierie des EIAH Dirigée par les Modèles) qui porte sur la réingénierie d'un scénario pédagogique. Il se focalise plus précisément sur l'analyse de traces collectées en session par un EIAH pour fournir à l'enseignant des indicateurs calculés.Dans notre contexte de travail, UTL (Usage Tracking Language) permet de définir des indicateurs sous une forme proche des patrons de conception. Il a été conçu pour répondre aux questions de capitalisation et de réutilisation. Par contre, UTL ne disposait initialement pas de moyens pour spécifier formellement la façon de calculer l’indicateur à partir des traces collectées. De plus, les approches par développement ad hoc d’indicateurs ne permettent pas de modéliser de façon formelle la méthode de calcul. En général, les patrons de conception se limitent à la description, ils ne peuvent donc pas être automatisés. Des descriptions textuelles dans UTL pour produire un indicateur à partir des traces ne permettent pas de générer automatiquement les valeurs d’un indicateur.Notre principal objectif de recherche a donc été de définir des modèles, des méthodes et des outils pour la formalisation et l’automatisation du calcul d’indicateurs. Pour cela, nous avons élaboré une nouvelle version d’UTL qui intègre un langage de combinaison de données nommé DCL4UTL, qui permet de modéliser des indicateurs sous une forme capitalisable, automatisable et réutilisable afin de fournir des indicateurs signifiants à l’enseignant/concepteur. Ces indicateurs peuvent être calculés en temps réel ou après une session, respectivement dans un contexte de tutorat ou de réingénierie du scénario pédagogique.L'originalité de notre approche réside dans le fait que cette version permet non seulement de capitaliser des savoir-faire sur les techniques d'analyse d'usage d'un EIAH, mais aussi, avec le langage DCL4UTL (1) de décrire formellement dans une forme générique des méthodes de modélisation et de calcul d’indicateurs à partir des traces collectées par un EIAH, (2) d’intégrer des fonctions externes (qui proviennent d’autres outils d’analyse), et (3) de créer des données intermédiaires paramétrées facilitant la modélisation et la réutilisation de la méthode de calcul d’indicateurs. Nous avons également développé un outil d’analyse pour calculer les indicateurs modélisés.Cette version est le résultat d'une étude théorique et d’une analyse de l’état de l’art, mais aussi de travaux exploratoires sur la modélisation d’indicateurs et l’analyse de traces. L’approche et le langage ont été validés par plusieurs expérimentations avec plusieurs EIAH existantsThe research topic of this thesis is a part of the REDIM (model driven re-engineering) research project. It focuses specifically on the analysis of tracks collected during the learning session by a TEL (Technology Enhanced Learning) system in order to provide teachers indicators calculated. In our work environment, UTL (Usage Tracking Language) allows users to define the indicators in a form close to the design patterns. It was designed to response capitalization and reuse questions. However, UTL did not initially have any means to formally specify how to calculate indicators based on tracks collected. In general, design patterns are limited to the description, they cannot be automated. In addition, textual descriptions in UTL to produce indicators from tracks do not allow generating automatically an indicator’s values.Our main research objective was therefore to define models, methods and tools for formalizing and automating the calculation of indicators. We propose an extension for UTL named DCL4UTL (Data Combination Language for UTL) to model indicators in a capitalizable, automatable and reusable form to provide meaningful indicators to teachers/designers. With this new version, the indicators can be calculated in real-time or after a learning session in the context of tutoring actions or the reengineering of learning scenarios, respectively.The originality of our approach (DCL4UTL) lies in the fact that this version not only capitalize know-how on analysis techniques of the use an TEL system, but also (1) formally describe models and calculation methods of indicators from tracks collected by a TEL system, (2) integrate external functions (from other analysis tools), and (3) create parameterized intermediate data facilitating the modeling and reuse of indicators’ calculation method. We have also developed an analysis tool to calculate modeled indicators. Our approach and language have been validated by several experiments with several existent TEL systems
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PIRES, Stéfani Silva. "Descoberta de causa-raiz em ocorrências de sistemas elétricos". Universidade Federal de Campina Grande, 2010. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1471.
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STEFANI SILVA PIRES - DISSERTAÇÃO PGCC 2010..pdf: 819684 bytes, checksum: 625f468cb174d699bf5b98131d1adf61 (MD5)Made available in DSpace on 2018-08-16T13:58:48Z (GMT). No. of bitstreams: 1 STEFANI SILVA PIRES - DISSERTAÇÃO PGCC 2010..pdf: 819684 bytes, checksum: 625f468cb174d699bf5b98131d1adf61 (MD5) Previous issue date: 2010-08-19
Este trabalho apresenta uma técnica de análise de causa-raiz para sistemas elétricos de potência. A análise de causa-raiz é uma forma de auxiliar o operador na compreensão da ocorrênciadefalha,interpretandoasocorrênciascomefeito"cascata"entreoselementosda rede. A técnica proposta utiliza o raciocínio baseado em regras, onde regras parametrizadas constroem um modelo de propagação com os diagnósticos de uma ocorrência de falha. A técnica permite apontar o elemento causador da ocorrência, e detalhar a sua propagação para os demais elementos em um modelo de causa-efeito. A utilização de regras parametrizadas traz grandes vantagens ao processo, permitindo que a técnica seja adaptável a alterações na topologia do sistema, e contribuindo para sua escalabilidade. Um estudo de caso foi elaborado para sua avaliação, no contexto da Companhia Hidro Elétrica do São Francisco (CHESF), onde foi desenvolvido um protótipo que implementa a técnica, e levantados um conjunto de regras parametrizadas e um conjunto de cenários de falha utilizando uma ferramenta de simulação de um ambiente real, o Simulop. Utilizamos também na avaliação, um conjunto de regressões, que são dados históricos armazenados pela CHESF. As regressões foramimportantesnaprimeirafasededefiniçãodatécnica,masapresentamproblemascomo afaltadedados,ecomportamentosinesperadosdosistema,ondeamargemdeacertodatécnica foi de 74%. Para o conjunto de cenários levantados com oSimulop, a técnica proposta conseguiu realizar com sucesso o processo de análise de causa-raiz, identificando a causaraiz da ocorrência em 100% dos cenários de falha, e detalhando sua propagação para todos os outros elementos da rede envolvidos em 89% dos cenários, onde a margem de erro é composta de cenários cuja propagação foi identificada apenas parcialmente, devido à falta de regras que contemplassem os cenários. Dessa forma, a técnica proposta se mostrou uma abordagem viável para a análise de causa-raiz em sistemas elétricos. A margem de acerto reduzida nas regressões, indica que, para ser aplicada em um ambiente operacional real, faz-se necessária a elaboração de um conjunto de regras mais abrangente e que possa contornar esses problemas.
This paper presents a root cause analysis technique for electric power systems. The root cause analysis is a way to assist the operator in understanding the occurrence of failure, interpreting the events cascade occurrences. The proposed technique uses a rule based reasoning, where parameterized rules construct a propagation model with diagnosis of an occurrence of failure. The technique allows to point out the element that causes the occurrence, and detailing its propagation to other elements in a cause and effect model. The use of parameterized rules brings major benefits to the process, allowing the technique to be adaptable to changes in system topology, and contributing to its scalability A case study was prepared for evaluation in the context of the Companhia Hidro Elétrica do São Francisco (CHESF). We developed a prototype that implements the technique, and raised a set of parameterized rules and a set of failure scenarios using a tool to simulate a real environment, the Simulop. We also used in the evaluation process, a set of regressions, which are historical data stored by CHESF. The regressions were important in the first phase of the technique, but they have problems such as lack of data, and unexpected behavior of the system, where the accuracy of the technique was 74%. For the set of scenarios created with Simulop, the proposed technique has achieved success in the root cause analysis process, identifying the root cause of the occurrence in 100% of failure scenarios, and detailing their propagation to all other equipments involved in 89% of scenarios, where the margin of error is composed of scenarios whose propagation has been identified only in part due to the lack of rules that contemplate these scenarios. Thus, the proposed technique proved to be a viable approach to root cause analysis in electrical systems. The reduced margin of success in the regressions , indicates that, to be applied to an operational environment, it is necessary to elaborate a comprehensive set of rules that can deal these problems.
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TSAO, YA-LAN, e 曹亞嵐. "Parameterized DSP Core for Communication System". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/67315834973933899323.
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博士國立中央大學
電機工程研究所
93
This thesis is a comprehensive work of a parameterized DSP core for embedded system. The overall research includes the parameterized architecture of the DSP core, multi-function data-path, input/output modes for embedded applications, low-power techniques, optional special function blocks and module generator. Parameterized DSP core is designed for optimal usage of different requirements in system applications. Owing to the parameterized structure, the DSP core can be custom made for dedicated system with parameters setting. The parameterized DSP core is especially suitable for an embedded system. The primary application is digital signal processing system which designed to achieve demodulation/synchronization with better performance and flexibility. We set up a novel design flow of embedded parameterized DSP core. The design flow includes a newly designed flexible parameterized DSP core structure, a module generator and a methodology to build the DSP core with optimal performance. The features in this DSP core include parameterized data-path, dual MAC unit, sub-word MAC and optional function-specific blocks for accelerating communication system modulation operations. This DSP core also has a low power structure, which includes the gray code addressing mode, pipeline sharing and a novel buffered hardware looping. Users can select the parameters and special function blocks based on the specification of their applications and then a synthesizable DSP core is generated in a proposed module generator with graph user interface. The proposed DSP core and the synthesizable RTL code have been verified with TSMC 0.35um SPQM, 0.25um 1P5M cell based and FPGA design flow.
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Teng, Jun-Xian, e 鄧君賢. "Parameterized and Embedded DSP Datapath for Communication Systems". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/08688439715373836824.
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碩士國立中央大學
電機工程研究所
90
Abstract In this thesis, a parameterized DSP datapath design and the parameterized DSP design flow are carried out. The proposed parameterized DSP is composed of DSP itself along with special blocks designed for communication systems. We term this kind processor as parameterized ASIC/DSP core. In the DSP datapath design, a subword MAC path with consideration of guard bit allocation is built for application in two different precision situations. Other than the subword MAC path, a correlator designed for WCDMA system is proposed. The correlator is designed to cooperate with DSP and share the same data bus with DSP. A parameterized DSP design flow is also proposed in this thesis, we divide issues during a parameterized DSP develop process into three sorts : arguments, control schemes, and structures. These issues are introduced and solved by establish an parameterized DSP generator, which is designed in Visual Basic and C language.
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Stahl, Karsten [Verfasser]. "Exploring the limits of parameterized system verification / Karsten Stahl". 2003. http://d-nb.info/971627908/34.
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Rosemblun, Marcela Laura. "Automatic differentiation: Overview and application to systems of parameterized nonlinear equations". Thesis, 1993. http://hdl.handle.net/1911/13777.
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Automatic Differentiation is a computational technique that allows the evaluation of derivatives of functions defined by computer programs. Derivatives are calculated by applying the chain rule of differential calculus to the sequence of elementary computations involved in the program. In this work, an overview of the theory and implementation of automatic differentiation is presented, as well as a description of the available software.
An application of automatic differentiation in the context of solving systems of parameterized nonlinear equations is discussed. In this application, the "differentiated" functions are implementations of Newton's method and Broyden's method. The iterates generated by the algorithms are differentiated with respect to the parameters. The results show that whenever the sequence of iterates converges to a solution of the system, the corresponding sequence of derivatives (computed by automatic differentiation) also converges to the correct value. Additionally, we show that the "differentiated" algorithms can be successfully employed in the solution of parameter identification problems via the Black-Box method.
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Stavrakakis, Kynthia Katherina. "Model Order Reduction Methods for Parameterized Systems in Electromagnetic Field Simulations". Phd thesis, 2012. https://tuprints.ulb.tu-darmstadt.de/3033/1/ThesisStavrakakisKynthia.pdf.
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The topic of this thesis falls in the field of system approximation. The original large-scale and parameter-dependent model is reduced to a smaller model which approximates the transfer function of the original model while the parameter dependence is retained in the reduced model. The simplified model is then succesfully used instead of the original model in a large variety of applications. The models stem from the Maxwell grid equations, which are obtained from the continuous Maxwell equations with the help of the Finite Integration Theory (FIT). In general, a variety of parameters is possible for electromagnetic field problems. In this work though, the focus has been set to material and geometry parameters with particular emphasis on the latter.
To this purpose, two main strategies are followed. The first strategy is based on already existing work on parametric order reduction which are not applicable in the form naturally obtained by the Maxwell grid equations. Therefore, a linearization step is shown that appropriately adapts the FIT systems to the desired form.
An alternative approach is based on using the system in the form directly obtained from the Maxwell grid equations, and defines the projection matrix of the parametric systems as the composition of local projection matrices. This method provides more flexibility in the geometry variation than the approach described above. The methods developed in this thesis have been applied to several numerical examples.
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Liu, Shi Hui. "Simulated validation of real-time reactive system with parameterized events". Thesis, 2003. http://spectrum.library.concordia.ca/2334/1/MQ83912.pdf.
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This thesis addresses the problems encountered during the simulated validation of real-time reactive systems at the design phase before the implementation. We assume that such systems are modeled as timed labeled transition systems, following the TROM methodology with parameterized events. In the previous work on the simulation, the simulator's algorithm had problems simulating some real-time reactive systems, such as the Train-Gate-Controller and Robotics system. This thesis aims to correct the flaws related to time conflicts in previous models, separate the Data Model module from the Validation tool, and add support for parameterized events in the simulator. As a system grows larger, assessing the performance of mission-critical applications become more important. This thesis proposes an assessment of a system's performance in terms of functionality, based on a Simulation, and illustrates its approach using the Robotics case study.
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Miller, Adam Robert. "Development and verification of parameterized digital signal processing macros for microelectronic systems". 2003. http://etd.utk.edu/2003/MillerAdam.pdf.
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Thesis (M.S.)--University of Tennessee, Knoxville, 2003.Title from title page screen (viewed Oct. 14, 2003). Thesis advisor: D.W. Bouldin. Document formatted into pages (v, 106 p. : ill. (some col.)). Vita. Includes bibliographical references (p. 49-50).