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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Application of artificial neural networks and colored petri nets on earthquake resilient water distribution systems

Balakrishnan, Nandini Kavanal, January 2008 (has links) (PDF)
Thesis (M.S.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed January 21, 2009) Includes bibliographical references.

Power system availability determination through Petri net simulation

Scruggs, James N. January 1995 (has links)
Thesis (M.S.)--Ohio University, March, 1995. / Title from PDF t.p.

Noodle : a three-dimensional net-based object-oriented development environment /

Cheng, Chuk-ping. January 1994 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 99-102).

Performance analysis of timed Petri nets by decomposition of the state space /

Suciu, Floarea, January 1998 (has links)
Thesis (M. Sc.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 63-67.

Inheritance in systems comprising reactive components : a behaviour perspective

El-Hassan, A. S. January 2000 (has links)
The aggregation hierarchy is one of the most significant data abstraction mechanisms that emerged as a result to semantic extensions to traditional systems analysis and design methods. The way inheritance works in this hierarchy is studied in this thesis. Special emphasis is placed on the behaviour of objects which are related via an aggregation hierarchy. A framework is introduced for capturing the behaviour of a system from the respective behaviour(s) of its components. This framework is based on a 3-level behaviour modelling hierarchy. One of the most significant contributions of this framework is the ability to apply inter-object interactions when building a behaviour model of a system. These interactions are significant in that they can yield totally distinct models of the systems functionality. Some of the notions that are supported by the behaviour modelling framework include unreachable and transient states, transition chains (cascades) and concurrency. The framework also enables the creation of behaviour model (semantic) hierarchies, wherein certain facets of the systems behaviour or functionality can be hidden (abstracted out) in a gradual fashion that suits the requirements of the problem domain. This creates what is effectively, distinct views of the behaviour or functionality of the system. The notions and concepts that are introduced here are verified and presented in a comprehensive case study that shows what can be achieved using these ideas. Suggestions are also made for future work which can help overcome some of the limitations introduced throughout this research.

Emission control in rotary kiln limestone calcination using Petri net models

Saini, Amit K. 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The idea of emission control is not new. Different industries have been putting in a lot of effort to limit the harmful emissions and support the environment. Keeping our earth green and safe for upcoming generations is our responsibility. Many cement plants have been shut down in recent years on account of high emissions. Controlling SO2, NOx and CO emissions using the Petri net models is an effort towards the clean production of cement. Petri nets do not just give a pictorial representation of emission control, but also help in designing a controller. A controlled Petri net can be potentially implemented to control the process parameters. In Chapter 2, we discuss the Petri nets in detail. In Chapter 3, we explain the modeling of emissions using the Petri nets. A controlled emission model is given in Chapter 4. A general Petri net model is considered to design the controller, which can be easily modified depending on the specific requirements and type of kiln in consideration. The future work given at the end is the work in progress and a neural network model will likely be integrated with the Petri net model.

Výukový nástroj pro barvené Petriho sítě / Educational Tool for Coloured Petri Nets

Navrátil, Ondřej January 2013 (has links)
Coloured Petri nets (CPN) are an extension of a standard place-transition Petri nets (P/T PN). Every token and place have its type (and eventually a value) and various inscriptions can be inserted into the net. CPN excel with great readibility and expresivity. At the same time, they carry a well-defined formal basis, which eases its computer simulation and allows limited verification of certain attributes to be performed. Motivation for doing this project is the simple fact that currently only one public software tool is available for CPN creation and simulation - CPNTools developed on the Aarhus university. The program, however, is quite complicated and hard to handle for an unexperienced user. The goal is to research capabilities and properties of both CPNs and CPNTools and on this basis design and implement a didactic application with swift and intuitive interface that helps users without deeper theoretical insight to get a grasp of the problematics.

Modeling, analysis, and simulation of Muzima fingerprint module based on ordinary and time Petri nets

Eadara, Archana 15 April 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the healthcare industry, several modern patient identification and patient matching systems have been introduced. Most of these implement patient identification by their first, middle and last names. They also use Social Security Number and other similar national identifiers. These methods may not work for many developing and underdeveloped countries where identifying a patient is a challenge with highly redundant and interchangeable first and last names of the patient, this is aggravated by the absence of a national identification system. In order to make the patient identification more efficient, Muzima, an interface of OpenMRS (Open source medical records system) introduced an additional identifier, fingerprint, through a module to the system. Ordinary and Time Petri nets are used to analyze this module. Chapter 1 introduces Muzima fingerprint module and describes the workflow of this interface followed by the related work, importance and applications of Petri nets. Chapter 2 introduces Ordinary and Time Petri nets using examples. Chapter 3 discusses about the mathematical modeling of the Muzima Fingerprint module using Petri nets. Chapter 4 explains the qualitative and quantitative analysis done on the Muzima fingerprint module. Chapter 5 discusses about the programming and simulation done to prove the theoretical results obtained. Chapter 6 provides the conclusion and future work for the thesis.

Test and diagnosis of discrete event systems using Petri nets / Test et diagnostic des systèmes à événements discrets par les réseaux de Petri

Pocci, Marco 23 September 2013 (has links)
Le test d’identification d’état d’un système à événement discret (SED) a pour but d’en identifier l’état final, lorsque son état initial est inconnu. Une solution classique à ce problème, en supposant que le SED n’ait pas de sorties observables, consiste à déterminer une séquences de synchronisation, c.à-d., une séquence d’événements d’entrée qui conduit le SED sur un état connu. Ce problème a été résolu dans les années 60’ à l’aide des automates. L’objectif principal de cette thèse est d’utiliser les réseaux de Petri (RdP) pour obtenir une résolution plus optimal de ce problème et pour une plus large classe de systèmes.Initialement, nous montrons que la méthode classique peut être aisément étendue aux RdP synchronisés. Pour cette classe de réseaux non-autonomes, toute transition est associée à un événement d’entrée.L’approche proposée est générale, dans la mesure où elle s’applique à des RdP bornés arbitraires. Cependant, elle engendre le problème d’explosion combinatoire du nombre d’états. Pour obtenir des meilleures solutions, nous considérons une classe spéciale de RdP : les graphes d’état (GdE). Pour ces réseaux, nous considérons d’abord les GdE fortement connexes et proposons des approches pour la construction de SS, qui exploitent les propriétés structurelles du réseau en évitant ainsi une énumération exhaustive de l’espace d’état. Ces résultats s’étendent aux GdE non fortement connexes et à tout RdP synchronisé composé de GdE. Enfin, nous considérons la classe des RdP non bornés et proposons des séquences qui synchronisent le marquage des places non bornées. Une boîte à outils fournit toutes les approches décrites et est appliquée à des différents bancs d’essai. / State-identification experiments are designed to identify the final state of a discrete event system (DES) when its initial state is unknown. A classical solution, assuming the DES has no observable outputs, consists in determining a synchronizing sequence (SS), i.e., a sequence of input events that drives the system to a known state. This problem was essentially solved in the 60’ using automata. The main objective of this thesis is to use Petri nets (PNs) for solving the state-identification problem more efficiently and for a wider class of systems.We start showing that the classical SS construction method based on automata can be easily applied to synchronized PNs, a class of non-autonomous nets where each transition is associated with an input event. The proposed approach is fairly general and it works for arbitrary bounded nets with a complexity that is polynomial with the size of the state space. However, it incurs in the state-space explosion problem.Looking for more efficient solutions, we begin by considering a subclass of PNs called state machines (SMs). We first consider strongly connected SMs and propose a framework for SS construction that exploits structural criteria, not requiring an exhaustive enumeration of the state space of the net. Results are further extended to larger classes of nets, namely non strongly connected SMs and nets containing SM subnets. Finally we consider the class of unbounded nets that describe infinite state systems: even in this case we are able to compute sequences to synchronize the marking of bounded places. A Matlab toolbox implementing all approaches previously described has been designed and applied to a series of benchmarks.

A geometric approach to integer optimization and its application for reachability analysis in Petri nets. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Finding integer solutions to linear equations has various real world applications. In the thesis, we investigate its application to the reachability analysis of Petri nets. Introduced by Petri in 1962, Petri net has been a powerful mathematical formalism for modeling, analyzing and designing discrete event systems. In the research community of Petri nets, finding a feasible path from the initial state to the target state in Petri net, known as reachability analysis, is probably one of the most important and challenging subjects. The reachability algebraic analysis is equivalent to finding the nonnegative integer solutions to a fundamental equation constructed from the Petri net. We apply our algorithm in this thesis to reachability analysis of Petri net by finding the nonnegative integer solutions to the fundamental equation. / Finding the optimal binary solution to a quadratic object function is known as the Binary Quadratic Programming problem (BQP), which has been studied extensively in the last three decades. In this thesis, by investigating geometric features of the ellipse contour of a concave quadratic function, we derive new upper and lower bounding methods for BQP. Integrating these new bounding schemes into a proposed solution algorithm of a branch-and-bound type, we propose an exact solution method in solving general BQP with promising preliminary computational results. Meanwhile, by investigating some special structures of the second order matrix and linear term in BQP, several polynomial time algorithms are discussed to solve some special cases of BQP. / In the realm of integer programming, finding integer solutions to linear equations is another important research direction. The problem is proved to be NP-Complete, and several algorithms have been proposed such as the algorithm based on linear Diophantine equations as well as the method based on Groebner bases. Unlike the traditional algorithms, the new efficient method we propose in this thesis is based on our results on zero duality gap and the cell enumeration of an arrangement of hyperplanes in discrete geometry. / Integer programming plays an important role in operations research and has a wide range of applications in various fields. There are a lot of research directions in the area of integer programming. In this thesis, two main topics will be investigated in details. One is to find the optimal binary solution to a quadratic object function, and the other is to find integer solutions to linear equations. / Gu, Shenshen. / Adviser: Wang Jun. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 98-103). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

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