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MODELING AND SIMULATION OF AN AUTOMATED PARALLEL PARKING SYSTEM USING HYBRID PETRI NETSRamesh, Keerthanaa January 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In recent years, there have been a lot of technology innovations to automate the day to day processes done by every person. These days the automobile manufacturers introduce new features in their cars, in order to improve customer experience, like Adaptive cruise control, Parallel park assist, etc. The objective of this thesis is to model an automated parallel parking system and to simulate the system behavior, by taking into account the high level events which happen when a car is parallel parked. The tool used in this thesis to model and simulate the system is Hybrid Petri net (HPN), which is versatile to model the real life systems. Chapter 1 deals with a brief introduction of the related work in Hybrid Petri net modeling of real life systems, automatic parallel parking systems and how the concept for modeling the parallel parking system was developed. Chapter 2 deals with the general introduction about Discrete, Continuous and Hybrid Petri nets and their dynamics which are essential for understanding this thesis. Chapter 3 deals with the development of the model and the various stages in the model development. Errors encountered in each stage is briefly discussed and the improvements are discussed in the next stage of development. This chapter concludes with the final integrated model and operation of the model. Chapter 4 deals with the discussion of results obtained when the model is tested in MATLAB and SIMHPN (which is a Matlab embedded simulation program). The results are compared, the system behavior is observed and the purpose of the thesis is justified. In Chapter 5, a conclusion is provided to summarize the entire thesis.
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A Novel Methodology for Timely Brain Formations of 3D Spatial Information with Application to Visually Impaired NavigationManganas, Spyridon 06 September 2019 (has links)
No description available.
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[en] ANALYSIS OF NATURAL LANGUAGE SCENARIOS / [pt] ANÁLISE DE CENÁRIOS EM LINGUAGEM NATURALEDGAR SARMIENTO CALISAYA 28 November 2016 (has links)
[pt] A análise de requisitos desempenha um papel fundamental no processo de
desenvolvimento de software. Neste sentido, representações de cenários baseados
em linguagem natural são muitas vezes utilizados para descrever especificações
de requisitos de software (SRS). Cenários descritos usando linguagem natural
podem ser ambíguos e, às vezes, imprecisos. Este problema é parcialmente devido
ao fato de que os relacionamentos entre os cenários são raramente representados
explicitamente. Como os cenários são utilizados como entrada para as actividades
subsequentes do processo de desenvolvimento de software (SD), é muito
importante facilitar a sua análise; especialmente para detectar defeitos devido a
informações erradas ou falta de informação. Este trabalho propõe uma abordagem
baseada em Redes de Petri e técnicas de Processamento de Linguagem Natural
como uma forma eficaz para analisar os cenários adquiridos, e que toma
descrições textuais de cenários (em conformidade com um metamodelo definido
neste trabalho) como entrada e gera um relatório de análise como saída. Para
facilitar a análise automática, os cenários são transformados em Redes de Petri
(Lugar/Transição) equivalentes. Os cenários e suas Redes de Petri resultantes
podem ser analisados automaticamente para avaliar algumas propriedades
relacionadas à desambiguidade, completeza, consistência e corretude. Os defeitos
identificados podem ser rastreados até os cenários, permitindo a sua revisão. Nós
também discutimos como desambiguidade, completeza, consistência e corretude
das SRSs baseadas em cenários podem ser decompostas em propriedades
relacionadas, e definimos heurísticas para encontrar indicadores de defeitos que
prejudicam estas propriedades. Avaliamos nosso trabalho, aplicando a nossa
abordagem de análise em quatro estudos de caso. Essa avaliação compara os
resultados obtidos pela nossa abordagem automatizada contra os resultados
obtidos por um processo de inspeção e com trabalhos relacionados. / [en] Requirements analysis plays a key role in the software development process.
Natural language-based scenario representations are often used for writing
software requirements specifications (SRS). Scenarios written using natural
language may be ambiguous, and, sometimes, inaccurate. This problem is
partially due to the fact that relationships among scenarios are rarely represented
explicitly. As scenarios are used as input to subsequent activities of the software
development process (SD), it is very important to enable their analysis; especially
to detect defects due to wrong information or missing information. This work
proposes a Petri-Net and Natural Language Processing (NLP) based approach as
an effective way to analyze the acquired scenarios, which takes textual description
of scenarios (conform to a metamodel defined in this work) as input and generates
an analysis report as output. To enable the automated analysis, scenarios are
translated into equivalent Place/Transition Petri-Nets. Scenarios and their
resulting Petri-Nets can be automatically analyzed to evaluate some properties
related to unambiguity, completeness, consistency and correctness. The identified
defects can be traced back to the scenarios, allowing their revision. We also
discuss how unambiguity, completeness, consistency and correctness of scenario-based SRSs can be decomposed in related properties, and define heuristics for
searching defect indicators that hurt these properties. We evaluate our work by
applying our analysis approach to four case studies. The evaluation compares the
results achieved by our tool-supported approach, with an inspection based
approach and with related work.
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An Exposition of Performance-Security Trade-offs in RANETs Based on Quantitative Network ModelsMiskeen, Guzlan M.A., Kouvatsos, Demetres D., Habib Zadeh, Esmaeil January 2013 (has links)
No / Security mechanisms, such as encryption and authentication protocols, require extra computing resources and therefore, have an adverse effect upon the performance of robotic mobile wireless ad hoc networks (RANETs). Thus, an optimal performance and security trade-off should be one of the main aspects that should be taken into consideration during the design, development, tuning and upgrading of such networks. In this context, an exposition is initially undertaken on the applicability of Petri nets (PNs) and queueing networks (QNs) in conjunction with their generalisations and hybrid integrations as robust quantitative modelling tools for the performance analysis of discrete flow systems, such as computer systems, communication networks and manufacturing systems. To overcome some of the inherent limitations of these models, a novel hybrid modelling framework is explored for the quantitative evaluation of RANETs, where each robotic node is represented by an abstract open hybrid G-GSPN_QN model with head-of-line priorities, subject to combined performance and security metrics (CPSMs). The proposed model focuses on security processing and state-based control and it is based on an open generalised stochastic PN (GSPN) with a gated multi-class 'On-Off' traffic and mobility model. Moreover, it employs a power consumption model and is linked in tandem with an arbitrary QN consisting of finite capacity channel queues with blocking for 'intra' robot component-to-component communication and 'inter' robot-to-robot transmission. Conclusions and future research directions are included.
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Modelagem e análise das cadeias de suprimentos globais e resilientes baseadas em rede de Petri. / Modeling and analysis of global and resilient supply chain based on Petri Net.Kano, Célia Hanako 16 June 2015 (has links)
Em um cenário de aumento de competitividade, crescente expectativa por inovações do produto e necessidade de atender diferentes perfis de consumidores, o conceito de gerenciamento de cadeias de suprimentos globais (GSCM) surge como uma estratégia para coordenar mais eficazmente as atividades dispersas geograficamente dos sistemas produtivos. Na adoção do GSCM, as organizações devem lidar com rupturas que impactam no gerenciamento das suas atividades, tais como a interrupção de vias de transporte, pane no fornecimento de energia, desastres naturais e até ataques terroristas. Nesse contexto, o trabalho introduz um procedimento sistematizado para modelagem das cadeias de suprimentos visto como um sistema a eventos discretos e sua análise por simulação das atividades do GSCM baseada em técnicas formais como a rede de Petri (PN) e o Production Flow Schema (PFS). Um exemplo é também apresentado para ilustrar e comprovar as vantagens do método proposto na análise do GSCM. / In a context of increasing competition, rising of expectations for product innovations and need to satisfy different consumer needs, the concept of global supply chain management (GSCM) emerges as a strategy to more efficiently coordinate the geographically dispersed activities of production systems. Adopting GSCM, organizations have to deal with external disruptions that impact management activities, such as transport interruption, power supply failure, natural disasters and terrorist attacks. In this way, a systematized procedure for modeling supply chains as a discrete event system and simulation analysis of GSCM activities based on formal techniques, such as Petri net (PN) and Production Flow Schema (PFS) is introduced. An example is also presented to illustrate and confirm the advantages of the proposed method for GSCM analysis.
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Identifizierung und Charakterisierung von Muskeldystrophie Duchenne modifizierenden Genen und StoffwechselwegenGrunwald, Stefanie 04 March 2010 (has links)
Hintergrund und Zielsetzung: DMD ist die häufigste Form der Muskeldystrophie im Kindesalter und bis heute unheilbar. Sie wird durch das Fehlen des Proteins Dystrophin verursacht, welches verschiedene Signaltransduktionswege beeinflusst. Das Anliegen der Arbeit ist die Untersuchung und Modulation von Signaltransduktionswegen, die als alternative Therapiestrategie den Verlust von Dystrophin kompensieren könnten. Experimentelle Strategie: Für die Charakterisierung von Dystrophin nachgeschalteten Prozessen wurden mRNA-Expressionsanalysen in Muskelgeweben von DMD-Patienten und einem DMD-Brüderpaar mit einem infrafamiliär unterschiedlichen Verlauf der DMD durchgeführt. Aus diesen Expressionsdaten wurde erstmalig ein Petri-Netz entwickelt, welches Dystrophin mit in diesem Zusammenhang bisher unbekannten Signaltransduktionswegen verknüpft. Das Petri-Netz wurde auf Netzwerkintegrität und –verhalten mittels Invarianten- (INA) und theoretischen Knockout- (Mauritius Maps) Analysen untersucht. Durch beide Methoden läßt sich der maßgebliche Teilsignalweg bestimmen. In diesem Signalweg wurden die Proteinaktivität und die Genexpression durch siRNA, Vektor-DNA und chemische Substanzen in humanen SkMCs moduliert. Anschließend wurden die Proliferation und die Vitalität der Zellen sowie auch die Expression auf mRNA- und Protein-Niveau untersucht. Ergebnisse: RAP2B und CSNK1A1 waren in dem DMD-Brüderpaar differentiell exprimiert und konnten erstmalig in einem neuen, komplexen Signalweg in Zusammenhang mit Dystrophin nachgeschalteten Prozessen dargestellt werden. Mittelpunkt dieses Signalweges ist die De- und Aktivierung des Transkriptionsfaktors NFATc. Seine Zielgene umfassen neben anderen den negativen Proliferationsfaktor p21, das Dystrophin homologe UTRN und den Differenzierungsfaktor MYF5. Folglich würde ein Anstieg von UTRN eine unerwünschte Reduktion der Proliferationsrate von Myoblasten implizieren. Letzteres konnte bereits nachgewiesen werden und stellte das Motiv für weitere Studien dar. Jedoch zeigten siRNA- und Vektor-DNA-Experimente, daß NFATc nicht der ausschlaggebende Faktor für diese Zielgene ist. Die Substanzen Deflazacort (DFZ) und Cyclosporin A (CsA) wurden dagegen beschrieben, die Aktivierung von NFATc zu beeinflussen. Die Ergebnisse zeigten, daß beide Substanzen die Proliferation von Myoblasten erhöhen können. Die gleichzeitige Applikation von DFZ und CsA führte zu einem Anstieg der UTRN-Expression. Schlußfolgerung: Die Modulation der Proliferation und UTRN-Expression ist unabhängig von einander möglich. Entsprechend der Grundidee der Arbeit zeichnet sich eine neue Therapiestrategie ab, welche Dystrophin nachgeschaltete Prozesse einbezieht. / Background and aim: DMD is the most common muscular dystrophy in childhood and incurable to date. It is caused by the absence of dystrophin, what influences several signal transduction pathways. The thesis is interested in the investigation and modulation of signal transduction pathways that may compensate the lack of dystrophin as an alternative therapy strategy. Experimental strategy: To study Dystrophin downstream pathways the mRNA expression of DMD patients and two DMD siblings with an intra-familially different course of DMD were analysed in muscle tissue. On the basis of these expression data a Petri net was first developed implicating signal transduction pathways and Dystrophin downstream cascades. Invariant (INA) and theoretical knockout (Mauritius Maps) analyses were applied for studying network integrity and behaviour. Both methods provide information about the most relevant part of the network. In this part modulation of protein activity and of gene expression using siRNA, vector-DNA, and chemical substances were performed on human SkMCs. Subsequently, the cells were studied by proliferation and vitality tests as well as expression analyses at mRNA and protein level. Results: RAP2B and CSNK1A1 were differently expressed in two DMD siblings, and first are part of a signal transduction pathway implicating Dystrophin downstream processes. The central point of this pathway is the de- and activation of the transcription factor NFATc. Its target genes are, among others, the negative proliferation factor p21, the Dystrophin homologue UTRN, and the differentiation factor MYF5. Consequently, an increase in UTRN implicates an undesirably reduced myoblast proliferation rate. Latter was found in DMD patients and was target for further studies. But, siRNA and vector DNA experiments showed that NFATc is not the decisive factor for the target genes. Deflazacort and cyclosporin A are known to influence the activation of NFATc. The results first showed that both substances do induce myoblast proliferation. The use of deflazacort in combination with cyclosporin A resulted in an increase of UTRN expression. Conclusion: The modulation of proliferation and UTRN-expression independently of each other is possible. According to the basic idea of this study, a new therapeutic strategy becomes apparent, which considers Dystrophin downstream processes.
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Konzepte der internetbasierten GerätesteuerungHoffmann, Gunnar 16 December 2011 (has links) (PDF)
Auf dem Gebiet der Gerätesteuerung existieren zahlreiche Insellösungen, die den Anspruch nach generischer Eignung nicht erfüllen. In besonderer Weise defizitär ist der Mangel an ganzheitlichen, offenen Frameworks, bei denen die Autokonfiguration, die Gerätezuordenbarkeit vor Ort, die Geräteüberwachbarkeit, die Inter-Gerätekommunikation und die Automatisierbarkeit von Abläufen Berücksichtigung finden.
Vor diesem Hintergrund öffnet die Arbeit mit einer Bestandsaufnahme von Technologien, die Einzelanforderungen der generischen Gerätesteuerung erfüllen. Sie bilden im weiteren Verlauf das potentielle Architekturfundament. Der Betrachtungsrahmen wird hierbei soweit ausgedehnt, dass relevante Verfahrensschritte vom Geräteanschluss bis zur automatisierten Generierung von User Interfaces abgedeckt sind.
Unter Rückgriff auf ausgewählte Technologien wird ein zweigliedriger Ansatz vorgestellt, der ein sehr breites Spektrum potentieller Steuergeräte unterstützt und gleichzeitig technologieoffen im Hinblick auf die Autogenerierung von User Interfaces ist. Höchstmögliche Funktionalität wird durch die Beschreibungssprache Device XML (DevXML) erreicht, deren Entwicklung einen Schwerpunkt der Arbeit darstellte.
In Anlehnung an die etablierte Petrinetztheorie werden Abhängigkeiten zwischen Zuständen und Funktionen formal beschrieben. Das Sprachvokabular von DevXML ermöglicht hierauf aufbauend Regeldefinitionen mit dem Ziel der Ablaufautomatisierung.
Das entworfene Framework wurde anhand von insgesamt elf praktischen Beispielen wie z.B. einem Schalter, einem Heizungsmodul, einem Multimeter bis hin zu virtuellen Geräten erfolgreich verifiziert.
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Contribution à la gestion des perturbations dans les systèmes manufacturiers à contraintes de temps / Contribution to the management of temporal disturbances in manufacturing systems with time constraintsM'halla, Anis 12 July 2010 (has links)
Les travaux proposés dans cette thèse s’intéressent à la commande et la surveillance d’une classe particulière de systèmes de production : les systèmes manufacturiers à contraintes de temps de séjour. Nous supposons dans l'étude que les ressources ont déjà été affectées et que l'ordre des opérations est déjà fixé par le module de planification/ordonnancement. Les hypothèses de fonctionnement répétitif avec et sans postes d'assemblage sont adoptées. De manière assez classique pour ce type de problématique, le formalisme utilisé est celui des Réseaux de Petri P-temporels pour l'étude des instants de débuts et de fins des opérations.Une étude de la robustesse des ateliers manufacturiers à contraintes de temps a été développée. La robustesse est abordée avec et sans modification de la commande relative à la robustesse active et à la robustesse passive respectivement, face aux perturbations temporelles. Un algorithme de calcul d'une borne supérieure de la robustesse passive est présenté. De plus, trois stratégies de commande robuste face aux perturbations temporelles ont été développées.Par ailleurs, l’incertitude dans les systèmes de production manufacturière à été étudié. Notre contribution dans ce cadre porte sur l’intégration des résultats concernant la robustesse dans la génération de symptômes et la classification des comptes rendus associés aux différentes opérations en utilisant la logique floue.Partant d’un système commandé, nous avons présenté en détail une démarche à suivre pour la mise en œuvre d’un modèle de surveillance en se basant sur les chroniques et les arbres de défaillance flous. Cette démarche est appliquée à un atelier de production laitière / The works proposed in this thesis are interested in controlling and monitoring of a particular class of production system : manufacturing job-shops with time constraints. We suppose in the study that the resources are allocated and the operations order is fixed by the module of planning/scheduling. The assumptions of repetitive functioning mode with and without assembling tasks are adopted. For this type of problems, the formalism of P-time Petri nets is used in order to study the operations time constraints.A study of the robustness of the manufacturing workshop to time constraints, has been developed. The robustness is approached with and without control reaction qualified as active robustness and passive robustness respectively, towards time disturbances. A computing algorithm of the upper bound of the passive robustness is presented. In addition, three robust control strategies facing time disturbances were developed.Furthermore, uncertainty in manufacturing systems has been studied. Our contribution in this context is by integration of the analytical knowledge of the robustness in the filtering mechanism of sensors signals that are associated to operations, by using fuzzy logic.Starting from a controlled system, we have presented in detail, a method to be followed for the implementation of a monitoring model based on the chronicles and fuzzy fault tree analysis. This approach is applied to a milk production unit
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Modelagem e análise das cadeias de suprimentos globais e resilientes baseadas em rede de Petri. / Modeling and analysis of global and resilient supply chain based on Petri Net.Célia Hanako Kano 16 June 2015 (has links)
Em um cenário de aumento de competitividade, crescente expectativa por inovações do produto e necessidade de atender diferentes perfis de consumidores, o conceito de gerenciamento de cadeias de suprimentos globais (GSCM) surge como uma estratégia para coordenar mais eficazmente as atividades dispersas geograficamente dos sistemas produtivos. Na adoção do GSCM, as organizações devem lidar com rupturas que impactam no gerenciamento das suas atividades, tais como a interrupção de vias de transporte, pane no fornecimento de energia, desastres naturais e até ataques terroristas. Nesse contexto, o trabalho introduz um procedimento sistematizado para modelagem das cadeias de suprimentos visto como um sistema a eventos discretos e sua análise por simulação das atividades do GSCM baseada em técnicas formais como a rede de Petri (PN) e o Production Flow Schema (PFS). Um exemplo é também apresentado para ilustrar e comprovar as vantagens do método proposto na análise do GSCM. / In a context of increasing competition, rising of expectations for product innovations and need to satisfy different consumer needs, the concept of global supply chain management (GSCM) emerges as a strategy to more efficiently coordinate the geographically dispersed activities of production systems. Adopting GSCM, organizations have to deal with external disruptions that impact management activities, such as transport interruption, power supply failure, natural disasters and terrorist attacks. In this way, a systematized procedure for modeling supply chains as a discrete event system and simulation analysis of GSCM activities based on formal techniques, such as Petri net (PN) and Production Flow Schema (PFS) is introduced. An example is also presented to illustrate and confirm the advantages of the proposed method for GSCM analysis.
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Maintenance modelling, simulation and performance assessment for railway asset management / Modélisation, simulation et évaluation de performances de la maintenance des infrastructures ferroviairesShang, Hui 25 September 2015 (has links)
Les travaux présentés dans ce manuscrit visent à développer des modèles de coût/performances pour améliorer les décisions de maintenance sur les infrastructures ferroviaires exploitées dans un environnement de plus en plus contraint: trafic accru, détérioration accélérée, temps de maintenance réduits. Les modèles de maintenance proposés sont construits à base de réseaux de Petri colorés ; ils sont animés par simulation de Monte Carlo pour estimer les performances (en termes de coût et de disponibilité) des politiques de maintenance considérées. Ils sont développés aux niveaux "composant" et "réseau", et plusieurs problèmes de maintenance différents sont étudiés. Au niveau "composant" (rail), des politiques de maintenance mettant en jeu différents niveaux d'information de surveillance sont comparées pour montrer l'intérêt de surveiller la détérioration graduelle du composant. L'effet de l'existence d'un délai de maintenance est également étudié pour les politiques conditionnelle et périodique. Au niveau système (ligne), une maintenance mettant en jeu différents types d'inspections complémentaires (automatique ou visuelle) est d'abord étudiée. On s'intéresse ensuite au cas de figure où l'évolution de la détérioration dépend du mode d'utilisation et de la charge de la voie : le problème de maintenance étudié vise alors à définir un réglage optimal des paramètres d'exploitation de la voie (vitesse limite) et de maintenance (délai d'intervention) / The aim of this thesis research work is to propose maintenance models for railways infrastructures that can help to make better maintenance decisions in the more constrained environment that the railway industry has to face, e.g. increased traffic loads, faster deterioration, longer maintenance planning procedures, shorter maintenance times. The proposed maintenance models are built using Coloured Petri nets; they are animated through Monte Carlo simulations to estimate the performance of the considered maintenance policies in terms of cost and availability. The maintenance models are developed both at the component and network levels, and several different maintenance problems are considered. At the rail component level, maintenance policies with different level of monitoring information (level of gradual deterioration vs binary working state) are compared to show the benefits of gathering monitoring information on the deterioration level. The effect of preventive maintenance delays is also investigated for both condition-based inspection policies and periodic inspection policies on a gradually deteriorating component. At the line level, a maintenance policy based on a two-level inspection procedure is first investigated. Then, considering the case when the deterioration process depends on the operation modes (normal vs limited speed), a maintenance optimization problem is solved to determine an optimal tuning of the repair delay and speed restriction
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