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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.
581

3D Navigation with Six Degrees-of-Freedom using a Multi-Touch Display

Ortega, Francisco Raul 07 November 2014 (has links)
With the introduction of new input devices, such as multi-touch surface displays, the Nintendo WiiMote, the Microsoft Kinect, and the Leap Motion sensor, among others, the field of Human-Computer Interaction (HCI) finds itself at an important crossroads that requires solving new challenges. Given the amount of three-dimensional (3D) data available today, 3D navigation plays an important role in 3D User Interfaces (3DUI). This dissertation deals with multi-touch, 3D navigation, and how users can explore 3D virtual worlds using a multi-touch, non-stereo, desktop display. The contributions of this dissertation include a feature-extraction algorithm for multi-touch displays (FETOUCH), a multi-touch and gyroscope interaction technique (GyroTouch), a theoretical model for multi-touch interaction using high-level Petri Nets (PeNTa), an algorithm to resolve ambiguities in the multi-touch gesture classification process (Yield), a proposed technique for navigational experiments (FaNS), a proposed gesture (Hold-and-Roll), and an experiment prototype for 3D navigation (3DNav). The verification experiment for 3DNav was conducted with 30 human-subjects of both genders. The experiment used the 3DNav prototype to present a pseudo-universe, where each user was required to find five objects using the multi-touch display and five objects using a game controller (GamePad). For the multi-touch display, 3DNav used a commercial library called GestureWorks in conjunction with Yield to resolve the ambiguity posed by the multiplicity of gestures reported by the initial classification. The experiment compared both devices. The task completion time with multi-touch was slightly shorter, but the difference was not statistically significant. The design of experiment also included an equation that determined the level of video game console expertise of the subjects, which was used to break down users into two groups: casual users and experienced users. The study found that experienced gamers performed significantly faster with the GamePad than casual users. When looking at the groups separately, casual gamers performed significantly better using the multi-touch display, compared to the GamePad. Additional results are found in this dissertation.
582

Strategische Interaktion realer Agenten: ganzheitliche Konzeptualisierung und Softwarekomponenten einer interdisziplinären Forschungsinfrastruktur

Tagiew, Rustam 11 February 2011 (has links)
Zum Verständnis menschlichen sozialen, administrativen und wirtschaftlichen Verhaltens, das als Spiel bzw. strategische Interaktion aufgefasst werden kann, reichen die rein analytischen Methoden nicht aus. Es ist nötig, Daten menschlichen strategischen Verhaltens zu sammeln. Basierend auf Daten lässt sich solches Verhalten modellieren, simulieren bzw. vorhersagen. Der theoretische Teil der Zielsetzung wird über praxisorientierte Konzeptualisierung strategischer Interaktion realer Agenten - Menschen und Maschinen - und gegenseitige Integration der Konzepte aus Spieltheorie und Multiagentensysteme erreicht, die über die bisherigen Ansätze hinausgehen. Der praktische Teil besteht darin, ein allgemein verwendbares System zu entwerfen, das strategische Interaktionen zwischen realen Agenten mit maximalen wissenschaftlichen Nutzen durchführen kann. Die tatsächliche Implementation ist eines der Ergebnisse der Arbeit. Ähnliche vorhandene Systeme sind GDL-Server (für Maschinen) [Genesereth u.a., 2005] und z-Tree (für Menschen) [Fischbacher, 2007]. Die Arbeit ist in drei Bereiche unterteilt - (1) Entwicklung von Sprachen für die Beschreibung eines Spiels, (2) ein auf diesen Sprachen basierendes Softwaresystem und (3) eine Offline-Analyse der u.a. mit dem System bereits gesammelten Daten als Beitrag zur Möglichkeiten der Verhaltensbeschreibung. Die Innovation dieser Arbeit besteht nicht nur darin ,einzelne Bereiche mit einander zu kombinieren, sondern auch Fortschritte auf jedem Bereich für sich allein zu erreichen. Im Bereich der Spielbeschreibungssprachen, werden zwei Sprachen - PNSI und SIDL - vorgeschlagen, die beide Spiele bei imperfekter Information in diskreter Zeit definieren können. Dies ist ein Fortschritt gegenüber der bisherigen Sprachen wie Gala und GDL. Speziell die auf Petrinetzen basierende Sprache PNSI kann gleichermaßen für Gameserver und für spieltheoretische Algorithmen von z.B. GAMBIT verwendet werden. Das entwickelte System FRAMASI basiert auf JADE [Bellifemine u.a., 2001] und ist den bisherigen Client-Server-Lösungen durch Vorteile der Multiagentensysteme voraus. Mit dem entstandenen System wurde bereits ein Experiment entsprechend den Standards der experimentellen Spieltheorie durchgeführt und somit die Praxistauglichkeit nachgewiesen. Das Experiment hatte als Ziel, Daten zur menschlichen Unvorhersagbarkeit und zur Vorhersagefähigkeit anderer zu liefen. Dafür wurden Varianten von \"Knobeln\" verwendet. Die Daten dieses Experiments sowie eines Experiments einer externen Arbeitsgruppe mit ähnlicher Motivation wurden mit Hilfe von Datamining analysiert. Dabei wurden die in der Literatur berichteten Gesetzmäßigkeiten des Verhaltens nachgewiesen und weitere Gesetzmäßigkeiten entdeckt.:Einführung Grundlagen Verwandte Arbeiten Sprachen für Spielbeschreibung Implementation der Spielinfrastruktur Beschreibung Strategischen Verhaltens Resümee Ergebnisse Ausblick / To understand human social, administrative and economic behavior, which can be considered as a game or strategic interaction, the purely analytical methods do not suffice. It is necessary to gather data of human strategic behavior. Based on data, one can model, simulate and predict such behavior. The theoretical part of the objective is achieved using a practice oriented conceptualization of the real agents\' - humans and machines - strategic interaction and mutual integration of the concepts from game theory and multi-agent systems, which go beyond the related work. The practical part is the design of an universally usable system that can perform the strategic interactions between real agents with maximum scientific benefit. The current implementation is one of the results of the work. Similar existing systems are GDL-server (for machines) [Genesereth et al., 2005] and z-Tree (for humans) [Fischbacher, 2007]. The work is divided in three fields - (1) development of languages for the description of a game, (2) a software system based on these languages and (3) an offline analysis of the data already gathered among other things using the system as a contribution to behavior definition facilities. The innovation of this work does not consist only in combining of the several fields to each other, but also in achieving of improvements in every field on its own. In the field of game definition languages, two languages are proposed - PNSI and SIDL, which both can define games of imperfect information in discrete time. It is an improvement comparing with hitherto languages as Gala and GDL. Especially, the Petri net based language PNSI can likewise be used for game servers and game theoretic algorithms like GAMBIT. The developed system FRAMASI is based on JADE [Bellifemine et al., 2001] and is ahead of the hitherto client-server solutions through the advantages of the multi-agent systems. Using the originated system, an experiment has been conducted according to the standards from the experimental game theory, and thus demonstrated the practicability. The experiment had the objective to provide data on the human unpredictability and the ability to predict others. Therefore, variants of Roshambo were used. The data from this experiment and from an experiment of an external workgroup with a similar motivation were analyzed using data mining. As results, the regularities of the behavior reported in literature have been demonstrated and further regularities have been discovered.:Einführung Grundlagen Verwandte Arbeiten Sprachen für Spielbeschreibung Implementation der Spielinfrastruktur Beschreibung Strategischen Verhaltens Resümee Ergebnisse Ausblick
583

Transaldolase 1 is required for Neutrophil Extracellular Trap (NET) Formation

Morath, Jakob Paul 12 June 2020 (has links)
Transaldolase-Mangel (TALDO) ist ein extrem seltener, angeborener Stoffwechseldefekt, von dem weltweit nur 34 Fälle bekannt sind. Der Defekt geht auf den Verlust des Enzyms Transaldolase 1 aus dem nicht-oxidativen Pentosephosphat-Weg (nicht-oxPPW) zurück und äußert sich in einem weiten Spektrum klinischer Symptome. Die schwerwiegendsten Folgen sind Leber- und Nierenmangelfunktionen, die zum sehr frühen Tod führen können. Desweiteren leiden 15 % der Patienten an wiederkehrenden Infektionen. Neutrophile Granulozyten (Neutrophile) sind die häufigsten weißen Blutkörperchen im Menschen und essentiell für die angeborene Immunantwort gegen Infektionserreger. Ich habe hier funktionale Aspekte von TALDO-Neutrophilen untersucht. Der oxidative Pentosephosphat-Weg (oxPPW) stellt das Reduktionsäquivalent NADPH bereit, welches indirekt für die Entstehung von reactive oxygen species (ROS)-abhängigen Neutrophil Extracellular Traps (NETs) verantwortlich ist. Der Beitrag des nicht-oxPPW zur ROS-abhängigen NET-Bildung ist bislang nicht bekannt. In dieser Arbeit konnte ich für Neutrophile aus drei TALDO-Patienten eine jeweils komplett abwesende Entstehung ROS-abhängiger NETs und einen deutlich verringerten oxidativen Burst nach PMA-Stimulation zeigen. Um diese Beobachtungen in einem unabhängigen Modelsystem zu bestätigen, habe ich mit Hilfe des CRISPR-Cas9-Systems, ‚knock-out‘ Mutanten von Transaldolase 1 und dessen Partnerenzym Transketolase in der Neutrophil-ähnlichen Zelllinie PLB-985 hergestellt. Die dergestalt genetisch manipulierten Zellen waren nicht mehr zu PMA-induziertem Zelltod in der Lage. Dies ist somit der erste genetische Beweis für die Abhängigkeit des oxidativen Burst und der Bildung von NETs vom nicht-oxPPW. Diese Erkenntnis trägt zum einen zum mechanistischen Verständnis der NET-Entstehung bei und liefert zum anderen eine potentielle Erklärung für einige der bei TALDO beobachteten Symptome. Desweiteren wurden einige der metabolischen Erfordernisse für die Bildung von NETs mit Hilfe von Inhibitoren untersucht. Die erhaltenen Erkenntnisse zeigen, dass das initiale Maximum des oxidativen Bursts für NET-Bildung unerheblich ist und vielmehr die ROS-Generierung nach ca. 50 Minuten entscheidende Bedeutung für diese hat. / Transdaldolase 1-deficiency (TALDO) is a rare genetic disease with only 34 described cases globally. Transaldolase 1 is part of the non-oxidative pentose phosphate pathway (PPP) and its deficiency results in many clinical symptoms including kidney and liver failure, which can lead to early child-mortality. Some of these patients suffer from recurrent infections, for example in the respiratory tract. Neutrophils are the most abundant white blood cells and essential for the innate immune defence against bacterial and fungal pathogens. The PPP generates reduced NADPH that is crucial for the generation of superoxide by the NADPH oxidase NOX2. In turn, NOX2 is essential for neutrophil extracellular trap (NET) formation. NETs occur through the neutrophil-specific cell death netosis and consist of chromatin decorated with granular proteins. Here I report that neutrophils of three TALDO patients did not make NETs. Deletion of transaldolase 1, and its partner enzyme transketolase, in the neutrophil-like PLB-985 cell line reduced ROS generation and cell death. This confirms that transaldolase 1 is required for NET formation. We present, to the best of our knowledge, the first genetic evidence that the non-oxidative PPP is required for ROS generation and NET formation. Furthermore, some of the metabolic requirements for NET formation were assessed. The obtained data indicate that the initial peak of the oxidative burst is irrelevant for NET formation but the ROS generation after 50 minutes on the contrary has crucial significance.
584

Modeling, monitoring and optimization of discrete event systems using Petri nets

Yan, Jiaxiang 29 January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Yan, Jiaxiang. M.S.E.C.E., Purdue University, May 2013. Modeling, Monitoring and Optimization of Discrete Event Systems Using Petri Nets. Major Professor: Lingxi Li. In last decades, the research of discrete event systems (DESs) has attracts more and more attention because of the fast development of intelligent control strategies. Such control measures combine the conventional control strategies with discrete decision-making processes which simulate human decision-making processes. Due to the scale and complexity of common DESs, the dedicated models, monitoring methods and optimal control strategies for them are necessary. Among various DES models, Petri nets are famous for the advantage in dealing with asynchronous processes. They have been widely applied in intelligent transportation systems (ITS) and communication technology in recent years. With encoding of the Petri net state, we can also enable fault detection and identification capability in DESs and mitigate potential human errors. This thesis studies various problems in the context of DESs that can be modeled by Petri nets. In particular, we focus on systematic modeling, asynchronous monitoring and optimal control strategies design of Petri nets. This thesis starts by looking at the systematic modeling of ITS. A microscopic model of signalized intersection and its two-layer timed Petri net representation is proposed in this thesis, where the first layer is the representation of the intersection and the second layer is the representation of the traffic light system. Deterministic and stochastic transitions are both involved in such Petri net representation. The detailed operation process of such Petri net representation is stated. The improvement of such Petri net representation is also provided with comparison to previous models. Then we study the asynchronous monitoring of sensor networks. An event sequence reconstruction algorithm for a given sensor network based on asynchronous observations of its state changes is proposed in this thesis. We assume that the sensor network is modeled as a Petri net and the asynchronous observations are in the form of state (token) changes at different places in the Petri net. More specifically, the observed sequences of state changes are provided by local sensors and are asynchronous, i.e., they only contain partial information about the ordering of the state changes that occur. We propose an approach that is able to partition the given net into several subnets and reconstruct the event sequence for each subnet. Then we develop an algorithm that is able to reconstruct the event sequences for the entire net that are consistent with: 1) the asynchronous observations of state changes; 2) the event sequences of each subnet; and 3) the structure of the given Petri net. We discuss the algorithmic complexity. The final problem studied in this thesis is the optimal design method of Petri net controllers with fault-tolerant ability. In particular, we consider multiple faults detection and identification in Petri nets that have state machine structures (i.e., every transition in the net has only one input place and one output place). We develop the approximation algorithms to design the fault-tolerant Petri net controller which achieves the minimal number of connections with the original controller. A design example for an automated guided vehicle (AGV) system is also provided to illustrate our approaches.
585

Modeling, Analysis, and Simulation of Two Connected Intersections Using Discrete and Hybrid Petri Nets

Yaqub, Omar Seddeq Omar 29 January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In recent decades, Petri nets (PNs) have been used to model traffic networks for different purposes, such as signal phase control, routing, and traffic flow estimation, etc. Because of the complex nature of traffic networks where both discrete and continuous dynamics come into play, the Hybrid Petri net (HPN) model becomes an important tool for the modeling and analysis of traffic networks. In Chapter 1 a brief historical summery about traffic systems control and then related work is mentioned followed by the major contributions in this research. Chapter 2 provides a theoretical background on Petri nets. In Chapter 3, we develop a HPN model for a single signalized intersection first, then we extend this model to study a simple traffic network that consists of two successive intersections. Time delays between different points of network are also considered in order to make the model suitable for analysis and simulation. In addition to HPN models, we also consider discrete Petri nets where their modeling simplicity enables the characterization of the occurrences of all events in the system. This discrete PN is particularly useful to give a higher-level representation of the traffic network and study its event occurrences and correlations. In Chapter 4, we build a discrete PN model to represent a traffic network with two successive intersections. However, we find that the model leads to unbounded places which cannot accurately reflect the dynamics of the traffic in terms of event occurrences. Hence, we introduce the Modified Binary Petri nets (MBPN) to overcome the limitation and resolve the confliction problem when we design our controllers. This MBPN model is a powerful tool and can be useful for the modeling and analysis of many other applications in traffic networks. Chapter 5 gives a summary for each chapter, provides conclusion and discusses future work for both discrete and hybrid Petri nets.
586

Proteins bind Neutrophil extracellular traps in specific patterns

Winkler, Jonay Moritz Julius 24 June 2024 (has links)
Neutrophile sind die häufigsten weißen Blutkörperchen im menschlichen Blut. Sie bilden die erste Verteidigungslinie und töten eindringende Krankheitserreger ab. Neutrophile extrazelluläre Fallen (NETs) sind netzartige Strukturen, die aus dekondensiertem Chromatin bestehen und mit zytotoxischen Proteinen dekoriert sind. NETs können Mikroben in vitro und in vivo einfangen und abtöten, sind aber auch für verschiedene Krankheiten verantwortlich. Frühere Studien haben eine spezifische Gruppe von 20-50 Neutrophilenproteinen identifiziert, die an NETs gebunden sind und von denen einige eine mikrobizide Wirkung haben. Wie diese Proteine an die NETs binden, wie sie interagieren und wie die Bindung ihre antimikrobielle Aktivität beeinflusst, ist noch nicht bekannt. In dieser Dissertation habe ich die Verteilung von acht neutrophilen Proteinen und Nukleosomen auf NETs mit Hilfe der Superauflösungsmikroskopie untersucht. Es wurden drei unabhängige Techniken mit Auflösungen von mehr als 90 nm verwendet. Die Nukleosomen bildeten auf den NETs periodische Cluster mit deutlich größeren Abständen im Vergleich zum kondensierten Chromatin. Drei NET-Proteine waren ebenfalls in periodischen Clustern auf den NETs lokalisiert und zwei von ihnen waren stark mit Nukleosomen kolokalisiert. Alle anderen analysierten Proteine zeigten keine Muster der Bindung an NETs. Zusammengenommen zeigen diese Ergebnisse, dass die Bindung von Proteinen an NETs zumindest teilweise spezifisch ist und teilweise durch Wechselwirkungen mit Nukleosomen vermittelt wird. Die erfolgreiche Einführung der superauflösenden Mikroskopie für schwierige NET-Proben in Kombination mit einem vorgeschlagenen rekonstituierten NET-System eröffnet neue Möglichkeiten für das Verständnis der molekularen Mechanismen der NET-Bildung und der Protein-Protein-Interaktion bei der NET-vermittelten Abtötung. / Neutrophils are the most abundant human white blood cell in circulation. They are the first line of defense and kill invading pathogens. Neutrophil Extracellular Traps (NETs) are weblike structures composed of decondensed chromatin decorated with cytotoxic proteins. NETs can trap and kill microbes in vitro and in vivo, but also mediate several diseases. Previous studies identified a specific set of 20-50 neutrophil proteins bound to NETs, several with microbicidal activity. It remains unknown how these proteins bind to NETs, how they interact and how binding influences their anti-microbial activity. In this dissertation, I studied the distribution of eight neutrophil proteins and nucleosomes on NETs using super-resolution microscopy. Three independent techniques with resolutions larger than 90nm were used. Nucleosomes formed periodic clusters on NETs, with significantly larger spacing compared to condensed chromatin. Three NET proteins also localized in periodic clusters on NETs and two of them strongly co-localized with nucleosomes. All other proteins analyzed showed no patterns binding to NETs. Taken together, these findings demonstrate that, at least some, protein binding to NETs is specific and in part mediated by interactions with nucleosomes. The successful introduction of super-resolution microscopy to the challenging NET samples in combination with a proposed reconstituted NET system opens new possibilities to understand the molecular mechanisms behind NET formation and protein-protein interaction in NET mediated killing.
587

Verification of asynchronous concurrency and the shaped stack constraint

Kochems, Jonathan Antonius January 2014 (has links)
In this dissertation, we study the verification of concurrent programs written in the programming language Erlang using infinite-state model-checking. Erlang is a widely used, higher order, dynamically typed, call-by-value functional language with algebraic data types and pattern-matching. It is further augmented with support for actor concurrency, i.e. asynchronous message passing and dynamic process creation. With decidable model-checking in mind, we identify actor communicating systems (ACS) as a suitable target model for an abstract interpretation of Erlang. ACS model a dynamic network of finite-state processes that communicate over a fixed, finite number of unordered, unbounded channels. Thanks to being equivalent to Petri nets, ACS enjoy good algorithmic properties. We develop a verification procedure that extracts a sound abstract model, in the form of an ACS, from a given Erlang program; the resulting ACS simulates the operational semantics of the input. Using this abstract model, we can conservatively verify coverability properties of the input program, i.e. a weak form of safety properties, with a Petri net model-checker. We have implemented this procedure in our tool Soter, which is the first sound verification tool for Erlang programs using infinite-state model-checking. In our experiments, we find that Soter is accurate enough to verify a range of interesting and non-trivial benchmarks. Even though ACS coverability is Expspace-complete, Soter's analysis of these verification problems is surprisingly quick. In order to improve the precision of our verification procedure with respect to recursion, we investigate an extension of ACS that allows pushdown processes: asynchronously communicating pushdown systems (ACPS). ACPS that satisfy the empty-stack constraint (a pushdown process may receive only when its stack is empty) are a popular subclass of ACPS with good decision and complexity properties. In the context of Erlang, the empty stack constraint is unfortunately not realistic. We introduce a relaxation of the empty-stack constraint for ACPS called the shaped stack constraint. Stacks that fit the shape constraint may reach arbitrary heights. Further, a process may execute any communication action (be it process creation, message send or retrieval) whether or not its stack is empty. We prove that coverability for shaped ACPS, i.e. ACPS that satisfy the shaped constraint, reduces to the decidable coverability problem for well-structured transition systems (WSTS). Thus, shaped ACPS enable the modelling and verification of a larger class of message passing programs. We establish a close connection between shaped ACPS and a novel extension of Petri nets: nets with nested coloured tokens (NNCT). Tokens in NNCT are of two types: simple and complex. Complex tokens carry an arbitrary number of coloured tokens. The rules of a NNCT can synchronise complex and simple tokens, inject coloured tokens into a complex token, and eject all tokens of a specified set of active colours to predefined places. We show that the coverability problem for NNCT is Tower-complete, a new complexity class for non-elementary decision problems introduced by Schmitz. To prove Tower-membership, we devise a geometrically inspired version of the Rackoff technique, and we obtain Tower-hardness by adapting Stockmeyer's ruler construction to NNCT. To our knowledge, NNCT is the first extension of Petri nets (belonging to the class of nets with an infinite set of token types) that is proven to have primitive recursive coverability. This result implies Tower-completeness of coverability for ACPS that satisfy the shaped stack constraint.
588

Methodology for the derivation of product behaviour in a Software Product Line / Méthodologie SPL pour la dérivation de modèles comportementaux des produits

Istoan, Paul 21 February 2013 (has links)
Le principal problème abordé dans cette thèse est la définition d'une nouvelle méthodologie SPL qui couvre les deux phases du processus et met l'accent sur la dérivation de modèles comportementaux des produits. Le chapitre 2 définit le cadre de cette thèse : les lignes de produits logiciels, les processus opérationnels et l'ingénierie dirigé par les modèles. Dans le chapitre 3, nous proposons une nouvelle méthodologie SPL centrée sur la dérivation de comportement des produits. Nous décrivons d'abord le courant principal de la méthodologie, et ensuite les différentes étapes. Dans le chapitre 4, nous proposons un nouveau langage spécifique domaine appelé CBPF pour la modélisation des fragments de processus opérationnels. Une approche dirigée par les modèles est suivie pour créer CBPF: syntaxe abstraite, syntaxe concrète graphique et sémantique translationnelles. Dans le chapitre 5, nous proposons plusieurs types de vérifications applicables aux fragments afin de déterminer leur justesse. Pour la vérification structurelle, est définit un ensemble des règles de cohérence qui doivent être valides pour chaque fragment réalisé avec CBPF. Pour vérifier le comportement, nous transformons d'abord les fragments dans des réseaux de Pétri équivalents. On peut alors vérifier des propriétés génériques mais aussi définir des propriétés spécifiques. Dans le chapitre 6, nous illustrons la méthodologie proposée en l'appliquant à une étude de cas à partir du domaine système de gestion de crise. Nous proposons également une suite d'outils qui supporte notre méthodologie. Le chapitre 7 décrit les améliorations possibles et les extensions aux contributions de cette thèse. Nous concluons la thèse dans le chapitre 8. / The major problem addressed in this thesis is the definition of a new SPLE methodology that covers both phases of the SPLE process and focuses on the derivation of behavioral models of SPL products. In Chapter 2 three research areas scope context of this thesis: Software Product Lines, Business Processes, and Model-Driven Engineering. Throughout Chapter 3, we propose a new SPLE methodology that focuses on the derivation of product behavior. We first describe the main flow of the methodology, and then detail the individual steps. In chapter 4 we propose a new domain specific language called CBPF created for modeling composable business process fragments. A model driven approach is followed for creating CBPF: definition of the abstract syntax, graphical concrete syntax and translational semantics. In Chapter 5 we propose several types of verifications that can be applied to business processfragments to determine their "correctness". For structural verification we definine a set of fragment consistency rules that should be valid for every business process fragment created with CBPF. To check behavioral correctness we first transform the business process fragment into an equivalent HCPN. We can then check generic properties but also define aset of fragment specific properties. In chapter 6 we exemplify the proposed SPL methodology by applying it to a case study from the crisis management system domain. We also propose a tool suite that supports our methodology. Chapter 7 describes possible improvements and extensions to the contributions of this thesis. We conclude the thesis in Chapter 8 and draw some conclusions.
589

Contribution à l'évaluation de sûreté de fonctionnement des architectures de surveillance/diagnostic embarquées. Application au transport ferroviaire / Contribution to embedded monitoring/diagnosis architectures dependability assesment. Application to the railway transport

Gandibleux, Jean 06 December 2013 (has links)
Dans le transport ferroviaire, le coût et la disponibilité du matériel roulant sont des questions majeures. Pour optimiser le coût de maintenance du système de transport ferroviaire, une solution consiste à mieux détecter et diagnostiquer les défaillances. Actuellement, les architectures de surveillance/diagnostic centralisées atteignent leurs limites et imposent d'innover. Cette innovation technologique peut se matérialiser par la mise en oeuvre d’architectures embarquées de surveillance/diagnostic distribuées et communicantes afin de détecter et localiser plus rapidement les défaillances et de les valider dans le contexte opérationnel du train. Les présents travaux de doctorat, menés dans le cadre du FUI SURFER (SURveillance active Ferroviaire) coordonné par Bombardier, visent à proposer une démarche méthodologique d’évaluation de la sûreté de fonctionnement d’architectures de surveillance/diagnostic. Pour ce faire, une caractérisation et une modélisation génériques des architectures de surveillance/diagnostic basée sur le formalisme des Réseaux de Petri stochastiques ont été proposées. Ces modèles génériques intègrent les réseaux de communication (et les modes de défaillances associés) qui constituent un point dur des architectures de surveillance/diagnostic retenues. Les modèles proposés ont été implantés et validés théoriquement par simulation et une étude de sensibilité de ces architectures de surveillance/diagnostic à certains paramètres influents a été menée. Enfin, ces modèles génériques sont appliqués sur un cas réel du domaine ferroviaire, les systèmes accès voyageurs des trains, qui sont critiques en matière de disponibilité et diagnosticabilité. / In the railway transport, rolling stock cost and availability are major concern. To optimise the maintenance cost of the railway transport system, one solution consists in better detecting and diagnosing failures. Today, centralized monitoring/diagnosis architectures reach their limits. Innovation is therefore necessary. This technological innovation may be implemented with embedded distributed and communicating monitoring/diagnosis architectures in order to faster detect and localize failures and to make a validation with respect to the train operational context.The present research work, carried out as part of the SURFER FUI project (french acronym standing for railway active monitoring) lead by Bombardier, aim to propose a methodology to assess dependability of monitoring/diagnosis architectures. To this end, a caracterisation et une modélisation génériques des monitoring/diagnosis architectures based on the stochastic Petri Nets have been proposed. These generic models take into account communication networks (and the associated failure modes), which constitutes a central point of the studied monitoring/diagnosis architectures. The proposed models have been edited and theoretically validated by simulation. A sensitiveness of the monitoring/diagnosis architectures to parameters has been studied. Finally, these generic models have applied to a real case of the railway transport, train passenger access systems, which are critical in term of availability and diagnosability.
590

Fluxo de dados em redes de Petri coloridas e em grafos orientados a atores / Dataflow in colored Petri nets and in actors-oriented workflow graphs

Borges, Grace Anne Pontes 11 September 2008 (has links)
Há três décadas, os sistemas de informação corporativos eram projetados para apoiar a execução de tarefas pontuais. Atualmente, esses sistemas também precisam gerenciar os fluxos de trabalho (workflows) e processos de negócio de uma organização. Em comunidades científicas de físicos, astrônomos, biólogos, geólogos, entre outras, seus sistemas de informações distinguem-se dos existentes em ambientes corporativos por: tarefas repetitivas (como re-execução de um mesmo experimento), processamento de dados brutos em resultados adequados para publicação; e controle de condução de experimentos em diferentes ambientes de hardware e software. As diferentes características dos dois ambientes corporativo e científico propiciam que ferramentas e formalismos existentes ou priorizem o controle de fluxo de tarefas, ou o controle de fluxo de dados. Entretanto, há situações em que é preciso atender simultaneamente ao controle de transferência de dados e ao controle de fluxo de tarefas. Este trabalho visa caracterizar e delimitar o controle e representação do fluxo de dados em processos de negócios e workflows científicos. Para isso, são comparadas as ferramentas CPN Tools e KEPLER, que estão fundamentadas em dois formalismos: redes de Petri coloridas e grafos de workflow orientados a atores, respectivamente. A comparação é feita por meio de implementações de casos práticos, usando os padrões de controle de dados como base de comparação entre as ferramentas. / Three decades ago, business information systems were designed to support the execution of individual tasks. Todays information systems also need to support the organizational workflows and business processes. In scientific communities composed by physicists, astronomers, biologists, geologists, among others, information systems have different characteristics from those existing in business environments, like: repetitive procedures (such as re-execution of an experiment), transforming raw data into publishable results; and coordinating the execution of experiments in several different software and hardware environments. The different characteristics of business and scientific environments propitiate the existence of tools and formalisms that emphasize control-flow or dataflow. However, there are situations where we must simultaneously handle the data transfer and control-flow. This work aims to characterize and define the dataflow representation and control in business processes and scientific workflows. In order to achieve this, two tools are being compared: CPN Tools and KEPLER, which are based in the formalisms: colored Petri nets and actors-oriented workflow graphs, respectively. The comparison will be done through implementation of practical cases, using the dataflow patterns as comparison basis.

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