El presente trabajo propone un modelo para las relaciones de producción de una economía, basándose en una red de Petri, aplicada sobre el modelo entrada salida dinámico, de Leontief. Para ello, se analiza dicho modelo a partir del origen y evolución de las cuentas nacionales, llegando a la obtención de la Matriz Insumo Producto Argentina en 1997. Se elabora un método de regionalizar dicha matriz, para el Sudoeste Bonaerense y se desarrolla un programa de computación, que permite obtener los resultados que arroja el modelo, comparándose los resultados con la información suministrada por la Dirección de Estadística Provincial del Ministerio de Economía de la Provincia de Buenos Aires. Los resultados obtenidos se comparan con los obtenidos por un modelo similar, que se aplica en Holanda, el modelo DIMITRI. / This paper proposes a model for the production relations of an economy, based on a Petri‟s network applied on the Leontief‟s dynamic input output model. To this end, discusses this model from the origin and evolution of national accounts, reaching the matrix input output Argentina in 1997. A method of regionalizing the matrix to the southwest of Buenos Aires will be obtained, and a computer program was developed to obtain outcomes of the model, thus, comparing the results with the information provided by the Dirección de Estadística Provincial del Ministerio de Economía de la Provincia de Buenos Aires. The results obtained are compared with obtained by a similar model that is applied in Netherland, the DIMITRI model.

Yes / System safety, reliability and risk analysis are important tasks that are performed throughout the system lifecycle to ensure the dependability of safety-critical systems. Probabilistic risk assessment (PRA) approaches are comprehensive, structured and logical methods widely used for this purpose. PRA approaches include, but not limited to, Fault Tree Analysis (FTA), Failure Mode and Effects Analysis (FMEA), and Event Tree Analysis (ETA). Growing complexity of modern systems and their capability of behaving dynamically make it challenging for classical PRA techniques to analyse such systems accurately. For a comprehensive and accurate analysis of complex systems, different characteristics such as functional dependencies among components, temporal behaviour of systems, multiple failure modes/states for components/systems, and uncertainty in system behaviour and failure data are needed to be considered. Unfortunately, classical approaches are not capable of accounting for these aspects. Bayesian networks (BNs) have gained popularity in risk assessment applications due to their flexible structure and capability of incorporating most of the above mentioned aspects during analysis. Furthermore, BNs have the ability to perform diagnostic analysis. Petri Nets are another formal graphical and mathematical tool capable of modelling and analysing dynamic behaviour of systems. They are also increasingly used for system safety, reliability and risk evaluation. This paper presents a review of the applications of Bayesian networks and Petri nets in system safety, reliability and risk assessments. The review highlights the potential usefulness of the BN and PN based approaches over other classical approaches, and relative strengths and weaknesses in different practical application scenarios. / This work was funded by the DEIS H2020 project (Grant Agreement 732242).

A fairly general model of the elevator system is presented. Coloured Petri Nets (CPN) and CPN tools are adopted as modeling tools. The model, which is independent of the number of floors and elevators, covers different stages of the elevator system in substantial detail. The model assists simulation-based analysis of different algorithms and rules which govern real elevator systems. The results prove the compatibility and applicability of this model in various situations and demonstrate the expressive power and convenience of CPN. / Thesis / Master of Applied Science (MASc)

Petri nets are a graphical construction with clearly de ned semantics which can model concurrent communicating systems in a formal manner similar to the way that automata theory can model formal language theory(Petri, 1962). As Dr. Carl Petri found the existing automata insu cient or too cumbersome for describing communicating systems others have found Petri Nets to be too cumbersome for e ectively reasoning about sophisticated, real world systems. In some cases these di culties were overcome by extending the theory of Petri Nets. Dr. Kurt Jensen developed the theory of Coloured Petri Nets (Jensen, 1981) for the purpose of generalizing and simplifying complex Petri Net models. This work incorporates Coloured Petri Nets and other theoretical extensions to describe a real world automated steel cutting system. During the course of this investigation the paper will formalize colours in the language of algebras and examine patterns related to timing conditions. / Thesis / Master of Science (MSc) / Petri nets can provide a graphical explanation of computer systems that have sophisticated communications. The graph has a precise mathematical meaning which allows it to be formally analyzed to prove many interesting properites of the net. There have been many extensions of the theory, some of which are incorporated to this model of an automated steel cutting machine. This thesis also presents the idea of colours, or data types, in the language of algebras.

No description available.

En esta tesis doctoral se presenta la formulación de una nueva técnica para el diagnóstico de fallos en sistemas complejos llamada el Método de Anidamiento Latente. Esta técnica, nace como respuesta a algunas tesis de doctorado predecesoras que contemplan el diagnóstico en relación a los problemas y conceptos de explosión combinacional, descomposición modular y fallos intermitentes dando paso con esta a nuevas técnicas de diagnóstico y supervisión enfocadas hacia el mantenimiento predictivo de sistemas como lo son: el seguimiento del estado o la monitorización de la condición. En relación a esta nueva técnica de anidamiento latente, se utilizan herramientas de modelado como lo son las Redes de Petri y algunas de sus extensiones más importantes como las del tipo Coloreadas e Híbridas las cuales le dan al método su base teórica y matemática. En el contexto de diagnóstico, la metodología ofrece una nueva posibilidad para la detección de fallos en diferentes tipos de sistemas complejos ya sea por su complejidad en cuanto a señales y variables, o a su funcionamiento y aplicación, sin importar que su naturaleza sea discreta, continua o híbrida como en la mayoría de casos complejos. Las diferentes características de la metodología según su diseño e implementación le permiten dar un paso adelante en la resolución de problemas de diagnóstico de manera sencilla y con modelos computacionales rápidos solucionando el paradigma clásico de diagnóstico: detección, aislamiento e identificación. Junto a las formulaciones teóricas y a los modelos realizados en la tesis, se presentan los resultados experimentales y de simulaciones obtenidos en dos sistemas complejos totalmente distintos en su aplicación, que permiten ver la viabilidad del método y su implicación práctica. Estas dos aplicaciones están enfocadas una hacia el diagnóstico de fallos en aerogeneradores (sistemas complejos de gran número de señales distintas), y la segunda al diagnóstico de fallos en semiconductores de potenc / Rodríguez Urrego, L. (2012). Diagnóstico de Fallos en Sistemas Complejos basado en el Método de Anidamiento Latente usando Redes de Petri Coloreadas e Híbridas [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17461

Les convertisseurs de puissance multicellulaires trouvent une place privilégiée dans le contrôle des systèmes de très forte puissance. Dans ce travail de thèse une nouvelle classe de convertisseurs de puissance est étudiée les Convertisseurs Multicellulaires Parallèles (CMP). La topologie de ces convertisseurs repose sur une association de n cellules de commutationinterconnectées par l'intermédiaire d'inductances indépendantes, appelées aussiinductances de liaison. Le CMP permet d'atteindre un courant de sortie égal à n fois le courant d'entrée du convertisseur, l'inconvénient majeur de ce type de convertisseur est le déséquilibrage des courants de branches . Dans le but de réduire et d'économiser le nombre de capteurs, nous avons proposé dans la première partie de la thèse une analyse d'observabilité spécifique à une classe de système dynamique hybride appelée Z(TN)-Observability et synthétisé un observateur hybride en utilisant l'algorithme super twisting. La deuxièmepartie du travail a été consacrée à la synthèse d'une loi de commande pour la régulation des courants de branches. En effet, le régulateur proposé est un régulateur hybride en basant sur la modélisation par réseaux de pétri de l'algorithme de contrôle. Enfin, Les deux parties théoriques sont suivies par une réalisation pratique d'un CMP à trois cellules de commutation pour valider les deux approches proposées. Les résultats expérimentaux nous ont montré les performances de l'observateur et le régulateur de courant et de tension de sortie. / This study deals with observability problems and control of the parallel multicell chopper. In the area of strong currents with high switching frequencies, new structures based on the combination of components have been developed. This type of chopper is a DC/DC static power converter which has an output current equals to n (n is the number of cells) times the source current. After recalling the dynamical equations of the converter, its hybrid dynamical behaviour and properties are highlighted. This particular hybrid system induces new and difficult observability problems, such problem can be tackled by a new observability concept [the Z(TN)-observability]. However, for a large number of switching cells in parallel, the complexity of the system makes it impossible to predict the transient behaviour of the converter and therefore all predimensioning. The main disadvantage of this type of converter is the imbalance branches of current with increasing number of cells. Therefore modelling and control with Petri net is proposed to solve the problems of imbalanced of currents and the voltage output regulation with variation of the load. The authors approaches are attested by several numerical simulations and experimental results considering noisy measurements and load variations.

Nous présentons dans ce travail de thèse des approches pour la spécification et la vérificationdes systèmes temporisés. La première partie concerne une méthode de spécification enutilisant les diagrammes états-transitions pour modéliser un système donné en partant d’unedescription textuelle. Cette méthode guide l’utilisateur pour le développement de la modélisation.Elle comporte plusieurs étapes et utilise des observateurs d’états et des événements afind’engendrer le diagramme états-transitions. Un outil qui implémente les différentes étapes de laméthode de spécification pour une application semi-automatique est présenté. La seconde partieconcerne une traduction des diagrammes états-transitions vers les réseaux de Petri colorés, cequi permet d’utiliser les méthodes de vérification. Nous prenons en considération dans cette traductionun ensemble important des éléments syntaxiques des diagrammes états-transitions, telsque la concurrence, la hiérarchie, etc. Un outil qui implémente la traduction pour un passageautomatique des diagrammes états-transitions vers les réseaux de Petri colorés est en cours de développement.La dernière partie concerne l’intégration des contraintes temporelles dans les deuxapproches précédentes. Nous définissons des annotations pour les diagrammes états-transitionsdont nous fournissons la syntaxe et la sémantique. Ces annotations seront ensuite utilisées dansla méthode de spécification et la traduction. Le but est de proposer des annotations faciles àcomprendre et à utiliser avec une syntaxe qui prend en compte des contraintes parmi les plusutilisées. / In order to specify and verify timed systems, we present in this thesis approaches using UMLstate machines and coloured Petri nets. Our first approach is a specification method that takesinto account a textual description of the system and generates the corresponding state machinediagram. This method helps a non-expert user to model a system in a structural way. We presenta tool that implements the specification method. Our second approach is the translation of UMLstate machine diagrams to coloured Petri nets diagrams. In this approach we take into account animportant set of UML state machine elements that allows the modelling of concurrent systems,etc. A tool that implements the approach and allows us to automate the translation is beingdeveloped. Finally, the last approach is the integration of time constraints in our specificationmethod and in our translation. We propose a set of annotations to model time in state machinediagrams, and we define the corresponding syntax and semantics.

Dentre as tendências de uso racional de recursos, principalmente energia, e da necessidade de assegurar a produtividade e qualidade na execução de atividades produtivas, destaca-se o conceito de edifício inteligente. Este ambiente materializa o conceito de integração dos sistemas prediais potencializando a otimização dos recursos e a eficiência do trabalho humano. Neste contexto, abordagens conceituais baseadas em sistemas a eventos discretos e técnicas derivadas de rede de Petri têm sido introduzidas como uma alternativa eficaz de modelagem e análise das soluções de integração dos sistemas prediais. Um resultado expressivo destas iniciativas são os métodos propostos para a modelagem e análise de estratégias de gerenciamento de sistemas de ar condicionado, utilizando uma abordagem híbrida, onde são considerados os aspectos de sistemas a eventos discretos e as variáveis de dinâmica contínua. Contudo, as abordagens e métodos existentes são limitados a soluções específicas de implementação, como os sistemas de ar condicionado com volume de ar contínuo. Assim, o presente trabalho introduz uma extensão destas abordagens para modelar e analisar soluções de automação predial que incluem sistemas de ar condicionado com volume de ar variável. A eficiência deste método na concepção e validação destas soluções é ilustrada através de um estudo de caso. / Among the trends of rational use of resources, especially energy, and the need to ensure productivity and quality in the implementation of productive activities, there is the concept of intelligent building. This environment materializes the concept of integrating building systems, powering the optimization of resources and the efficiency of human labor. In this context, conceptual approaches that are based on systems of discreet events and techniques, which are derived from the Petri nets, have been introduced as an effective alternative to modeling and analysis of solutions of building systems integration. A significant result of these initiatives are the proposed methods for modeling and the analysis of strategies for air conditioning systems management using a hybrid approach where the aspects of systems of discreet events and the variables of continuing dynamic are considered. However, the existing methods and approaches are limited to their specific implementation solutions, such as air conditioning systems with continuous volume of air. Thus, this work introduces an extension of these approaches to model and analyze the building automation solutions that include air conditioning systems with variable volume of air. The efficiency of this method in the design and validation of these solutions is illustrated through a case study.

A globalização reforça a necessidade das empresas aprimorarem seus processos e produtos continuamente para se manterem competitivas e atenderem às expectativas de um mercado dinâmico e de acionistas cada vez mais exigentes, que buscam maximizar seus lucros. A melhoria contínua acima mencionada não se refere apenas à qualidade percebida pelo consumidor final, mas também à qualidade e confiabilidade dos processos de produção. Desta forma, quando as empresas têm melhores processos, melhores são os produtos originados e também os seus custos. Porém, a questão é como esses processos são modelados na fase de projeto e como ferramentas de qualidade, sobretudo o Seis Sigma metodologia mais em voga na atualidade podem utilizar tais modelos para obter melhores resultados. Essa dissertação propõe a utilização de ferramentas de modelagem e simulação tais como as Redes de Petri para modelagem de processos produtivos fornecem um modelo formal para a representação de sistemas de produção, capturando aspectos inerentes a tais sistemas como concorrência, paralelismo e sincronização suportando a aplicação da metodologia Seis Sigma, a qual geralmente atua somente no nível de melhoria do processo produtivo e não do projeto que o originou. Dessa forma, essa dissertação trás uma proposta de integração entre os times que projetam o processo e os que executam a produção, demonstrando tal viabilidade por meio da análise dos projetos/modelos durante a aplicação da metodologia Seis Sigma. É realizado um estudo de caso na estamparia de uma indústria automotiva que ilustra a aplicação da metodologia proposta. / The globalization strengthens the necessity for companies to improve its processes and products in order to remains competitive and to attend expectations of a dynamic market and shareholders each time more demanding and eager to maximize their profits. The continuous improvement mentioned above, is not related only to the quality perceived by the final consumer, but also to the quality and reliability of the production processes. Therefore, as better processe the company gets, as better would be their final products and as lower would be the costs. However, the question is wheter a continuous improvement using Six Sigma could benefit from the design documentation for the target process returning also an improved documentation after the cycle is completed. This work considers the use of Petri Nets for production processes modeling - even if any other design and modeling representation would return similar results - supporting the Six Sigma methodology application. The main result is a proposition of continuous improvement life cycle that maintains the design documentation consistent and up-to-date. Thus, this work pursuits the integration between the teams that design processes and those who implement them in the manufacturing plant. To show the potential of the models analysis during Six Sigma projects a case study is analyzed for the Press Shop area in an Automotive Industry.