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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.
31

Industrial case study on the integration of SysML and AUTOSAR with triple graph grammars

Giese, Holger, Hildebrandt, Stephan, Neumann, Stefan, Wätzoldt, Sebastian January 2012 (has links)
During the overall development of complex engineering systems different modeling notations are employed. For example, in the domain of automotive systems system engineering models are employed quite early to capture the requirements and basic structuring of the entire system, while software engineering models are used later on to describe the concrete software architecture. Each model helps in addressing the specific design issue with appropriate notations and at a suitable level of abstraction. However, when we step forward from system design to the software design, the engineers have to ensure that all decisions captured in the system design model are correctly transferred to the software engineering model. Even worse, when changes occur later on in either model, today the consistency has to be reestablished in a cumbersome manual step. In this report, we present in an extended version of [Holger Giese, Stefan Neumann, and Stephan Hildebrandt. Model Synchronization at Work: Keeping SysML and AUTOSAR Models Consistent. In Gregor Engels, Claus Lewerentz, Wilhelm Schäfer, Andy Schürr, and B. Westfechtel, editors, Graph Transformations and Model Driven Enginering - Essays Dedicated to Manfred Nagl on the Occasion of his 65th Birthday, volume 5765 of Lecture Notes in Computer Science, pages 555–579. Springer Berlin / Heidelberg, 2010.] how model synchronization and consistency rules can be applied to automate this task and ensure that the different models are kept consistent. We also introduce a general approach for model synchronization. Besides synchronization, the approach consists of tool adapters as well as consistency rules covering the overlap between the synchronized parts of a model and the rest. We present the model synchronization algorithm based on triple graph grammars in detail and further exemplify the general approach by means of a model synchronization solution between system engineering models in SysML and software engineering models in AUTOSAR which has been developed for an industrial partner. In the appendix as extension to [19] the meta-models and all TGG rules for the SysML to AUTOSAR model synchronization are documented. / Bei der Entwicklung komplexer technischer Systeme werden verschiedene Modellierungssprachen verwendet. Zum Beispiel werden bei der Entwicklung von Systemen in der Automobilindustrie bereits früh im Entwicklungsprozess Systemmodelle verwendet, um die Anforderungen und die grobe Struktur des Gesamtsystems darzustellen. Später werden Softwaremodelle verwendet, um die konkrete Softwarearchitektur zu modellieren. Jedes Modell stellt spezifische Entwurfsaspekte mit Hilfe passender Notationen auf einem angemessenen Abstraktionsniveau dar. Wenn jedoch vom Systementwurf zum Softwareentwurf übergegangen wird, müssen die Entwicklungsingenieure sicherstellen, dass alle Entwurfsentscheidungen, die im Systemmodell enthalten sind, korrekt auf das Softwaremodell übertragen werden. Sobald danach auch noch Änderungen auftreten, muss die Konsistenz zwischen den Modellen in einem aufwändigen manuellen Schritt wiederhergestellt werden. In diesem Bericht zeigen wir, wie Modellsynchronisation und Konsistenzregeln zur Automatisierung dieses Arbeitsschrittes verwendet und die Konsistenz zwischen den Modellen sichergestellt werden können. Außerdem stellen wir einen allgemeinen Ansatz zur Modellsynchronisation vor. Neben der reinen Synchronisation umfasst unsere Lösung weiterhin Tool-Adapter, sowie Konsistenzregeln, die sowohl die Teile der Modelle abdecken, die synchronisiert werden können, als auch die restlichen Teile. Der Modellsynchronisationsalgorithmus basiert auf Tripel-Graph-Grammatiken und wird im Detail erläutert. An Hand einer konkreten Transformation zwischen SysML- und AUTOSAR-Modellen, die im Rahmen eines Industrieprojektes entwickelt wurde, wird der Ansatz demonstriert. Im Anhang des Berichts sind alle TGG-Regeln für die SysML-zu-AUTOSAR-Transformation dokumentiert.
32

Integrating models and simulations of continuous dynamic system behavior into SysML

Johnson, Thomas Alex 05 May 2008 (has links)
Contemporary systems engineering problems are becoming increasingly complex as they are handled by geographically distributed design teams, constrained by the objectives of multiple stakeholders, and inundated by large quantities of design information. According to the principles of model-based systems engineering (MBSE), engineers can effectively manage increasing complexity by replacing document-centric design methods with computerized, model-based approaches. In this thesis, modeling constructs from SysML and Modelica are integrated to improve support for MBSE. The Object Management Group has recently developed the Systems Modeling Language (OMG SysML ) to provide a comprehensive set constructs for modeling many common aspects of systems engineering problems (e.g. system requirements, structures, functions). Complementing these SysML constructs, the Modelica language has emerged as a standard for modeling the continuous dynamics (CD) of systems in terms of hybrid discrete- event and differential algebraic equation systems. The integration of SysML and Modelica is explored from three different perspectives: the definition of CD models in SysML; the use of graph transformations to automate the transformation of SysML CD models into Modelica models; and the integration of CD models and other SysML models (e.g. structural, requirements) through the depiction of simulation experiments and engineering analyses. Throughout the thesis, example models of a car suspension and a hydraulically-powered excavator are used for demonstration. The core result of this work is the provision of modeling abilities that do not exist independently in SysML or Modelica. These abilities allow systems engineers to prescribe necessary system analyses and relate them to stakeholder concerns and other system aspects. Moreover, this work provides a basis for model integration which can be generalized and re-specialized for integrating other modeling formalisms into SysML.
33

Aspectos iniciais modelados com uma extensão da SYSML

Oliveira, Kênia Santos de 19 February 2013 (has links)
Aspect Oriented Programming has been proposed in order to handle crosscutting concerns in an ecient manner. Initial proposals in this area have been applied to the source code. Subsequently, aspects were considered to be implemented in other phases of software development such as Requirements Engineering and Software Architecture. There are several advantages in identifying aspects at the requirements level and architecture level such as detecting conicts of interest, improving the requirements modularity, reducing costs of software maintenance and preserving the notion of aspects in software development process ensuring traceability. Therefore, the purpose of this work is to develop a model to represent aspects at the requirements level and the architecture level. The requirements model denes the activities of identication of aspect requirements, both functional and non-functional, separation and composition of aspect requirements and identication of conict between aspect requirements. Since dierent stakeholders need to view the system from dierent perspectives, the architecture model allows to represent dierent views considering the representation with aspects. The proposed views are structural, use case + requirements and development. Compared to other analysed approaches, the proposed models in this work represent important characteristics that others models do not represent, such as maintaining traceability of aspects between requirements and the architecture level. In order to represent the models, extensions to the SysML modeling language were proposed. / A Programação Orientada a Aspectos foi proposta com o objetivo de manipular interesses transversais de uma maneira eciente. Propostas iniciais nesta área foram aplicadas no código fonte. Posteriormente, aspectos foram considerados para serem aplicados em outras fases do desenvolvimento de software tais como Engenharia de Requisitos e Arquitetura de Software. Há várias vantagens em identicar aspectos no nível de requisitos e no nível arquitetural, tais como detectar inicialmente conitos de interesses, melhorar a modularidade dos requisitos, reduzir custos de manutenção de software e preservar a noção de aspectos no processo de desenvolvimento de software garantindo rastreabilidade. Portanto, o propósito desse trabalho é desenvolver um modelo para representar aspectos no nível de requisitos e no nível arquitetural. O modelo de requisitos dene as atividades de identicação de requisitos aspectuais tanto de origem funcional quanto não-funcional, separação e composição de requisitos e requisitos aspectuais e identicação de conitos entre requisitos aspectuais. Uma vez que diferentes stakeholders necessitam visualizar o sistema a partir de diferentes perspectivas, o modelo de arquitetura permite representar diferentes visões considerando a representação com aspectos. As visões propostas são a estrutural, a de casos de uso + requisitos, e a de desenvolvimento. Em comparação com outras abordagens analisadas, os modelos propostos nesse trabalho cobrem importantes características que os outros modelos não cobrem, como por exemplo, manter a rastreabilidade de aspectos entre os níveis de requisitos e de arquitetura. Para representar os modelos, extensões da linguagem de modelagem SysML foram propostas. / Mestre em Ciência da Computação
34

Conception et déploiement des Systèmes de Production Reconfigurables et Agiles (SPRA) / Design and deployment of Reconfigurable and Agile Manufacturing Systems (RAMS)

Chalfoun, Imad 26 September 2014 (has links)
L'industrie est aujourd'hui, comme elle a toujours été, une pierre angulaire de l'économie pour chaque pays développé. Avoir une base solide en entreprises industrielles est très important parce qu’elles poussent et stimulent tous les autres secteurs de l'économie, et offrent également une grande variété d'emplois qui apporte des bonnes conditions de vie dans de nombreux secteurs de la société. L’augmentation de la concurrence mondiale, l’évolution rapide du marché, la nécessité de créer des entreprises stables avec des usines rentables obligent la mise en oeuvre d’une démarche globale prenant en compte à la fois les aspects techniques, économiques, logistiques et sociétaux lors de la conception d’un système de production innovant. L’objectif de cette thèse est de contribuer au développement d’un concept innovant de Systèmes de Production Reconfigurables et Agiles (SPRA) permettant de s'adapter rapidement et efficacement aux exigences imposées du marché, des clients, de la technologie des procédés, de l’environnement et de la société afin que l’entreprise soit dynamique, compétitive et rentable. Dans ces travaux de thèse, la proposition d'un modèle générique et la caractérisation de ce nouveau type de système de production ont été décrits en utilisant le langage de modélisation des systèmes complexes (SysML : Systems Modeling Language). Ensuite, nous avons développé un processus de reconfiguration qui représente une démarche à suivre pour concevoir et implanter une nouvelle configuration. De plus, un pilotage opérationnel adapté au SPRA a été introduit. Enfin, quelques travaux développés au cours de cette thèse ont été partiellement déployés sur un démonstrateur industriel au sein de la plate-forme AIP-PRIMECA Auvergne. / Industry is, today as it has always been, a cornerstone of the economy for any developed country. Having a strong manufacturing base is very important because it impels and stimulates all the other sectors of the economy. It provides a wide variety of job, which bring higher standards of living to many sectors of society, and builds a strong middle class. Increasing global competition, rapid changes in the marketplace and the need to create stable companies with profitable plants require the implementation of a global approach, taking into account technical, economic, logistic and societal aspects in the design of an innovative manufacturing system. The aim of this dissertation is to contribute to the development of an innovative concept of Reconfigurable and Agile Manufacturing Systems (RAMS) to adapt quickly and effectively to the requirements imposed by markets, customers, technology processes, the environment and society, to ensure that the enterprise is dynamic, competitive and profitable. In this thesis work, the characterization and proposal of a generic model for this new type of manufacturing system have been described using the language of complex systems modeling (SysML: Systems Modeling Language). We have developed a reconfiguration process that represents the approach to follow in the design and implementation of a new configuration. In addition, the operational control of a RAMS has been introduced. Finally, some works developed in this thesis have been partially deployed on an industrial demonstrator within the AIP-PRIMECA Auvergne organisation.
35

Analyse formelle de spécifications hybrides à partir de modèles SysML pour la validation fonctionnelle des systèmes embarqués / Formal analysis of hybrid specifications from SysML models for functional validation of embedded systems specifications

Medimegh, Slim 20 December 2018 (has links)
Le logiciel embarqué est devenuaujourd’hui incontournable dans la plupart dessecteurs industriels. Ce dernier fait appel engénéral à des connaissances métier différentes.L’ensemble du système (le logiciel et sonenvironnement) est ainsi spécifié d’une manièrehétérogène, avec des parties discrètes et d’autrescontinues. La simulation de ces systèmeshybrides nécessite des données précises et unesynchronisation des changements continus avecles transitions discrètes. Mais, dans les premièresphases de conception, l’absence des informationsempêche de simuler le système numériquement.Dans notre thèse, nous présentons un nouveaulangage qualitatif dédié à la simulationqualitative des systèmes hybrides. Ce nouveaulangage consiste à modéliser les relations entreles variables du système. Il est implémenté dansDiversity, un moteur d’exécution symbolique,pour construire les traces du système. Nousavons appliqué cette approche à l’analyse desmodèles SysML, en utilisant une transformationM2M à partir de SysML vers un langage pivot,une transformation M2T à partir de ce langagevers Diversity. Nous avons aussi analysé lestraces brutes de l’exécution symbolique deDiversity pour construire les comportementsqualitatifs du système. / Embedded software has becomeessential in most industrial sectors. The latterusually involves various business knowledge.The whole system (the software and itsenvironment) is specified in a heterogeneousform, with discrete and continuous parts.Simulating these hybrid systems requiresprecise data and synchronization of continuouschanges and discrete transitions. However, inthe first design steps, missing informationforbids numerical simulation. We present in ourthesis a new qualitative language for qualitativesimulation of hybrid systems, which consists incomputing the relationships between the systemvariables. This language is implemented in theDiversity symbolic execution engine to build thetraces of the system. We apply this approach tothe analysis of SysML models, using an M2Mtransformation from SysML to a pivot language,an M2T transformation from this language toDiversity. We also analyze the brutal symbolictraces obtained by Diversity to build the realqualitative behaviors of the system.
36

Model Based Systems Engineering Approach to Autonomous Driving : Application of SysML for trajectory planning of autonomous vehicle

Veeramani Lekamani, Sarangi January 2018 (has links)
Model Based Systems Engineering (MBSE) approach aims at implementing various processes of Systems Engineering (SE) through diagrams that provide different perspectives of the same underlying system. This approach provides a basis that helps develop a complex system in a systematic manner. Thus, this thesis aims at deriving a system model through this approach for the purpose of autonomous driving, specifically focusing on developing the subsystem responsible for generating a feasible trajectory for a miniature vehicle, called AutoCar, to enable it to move towards a goal. The report provides a background on MBSE and System Modeling Language (SysML) which is used for modelling the system. With this background, an MBSE framework for AutoCar is derived and the overall system design is explained. This report further explains the concepts involved in autonomous trajectory planning followed by an introduction to Robot Operating System (ROS) and its application for trajectory planning of the system. The report concludes with a detailed analysis on the benefits of using this approach for developing a system. It also identifies the shortcomings of applying MBSE to system development. The report closes with a mention on how the given project can be further carried forward to be able to realize it on a physical system. / Modellbaserade systemteknikens (MBSE) inriktning syftar till att implementera de olika processerna i systemteknik (SE) genom diagram som ger olika perspektiv på samma underliggande system. Detta tillvägagångssätt ger en grund som hjälper till att utveckla ett komplext system på ett systematiskt sätt. Sålunda syftar denna avhandling att härleda en systemmodell genom detta tillvägagångssätt för autonom körning, med särskild inriktning på att utveckla delsystemet som är ansvarigt för att generera en genomförbar ban för en miniatyrbil, som kallas AutoCar, för att göra det möjligt att nå målet. Rapporten ger en bakgrund till MBSE and Systemmodelleringsspråk (SysML) som används för modellering av systemet. Med denna bakgrund, MBSE ramverket för AutoCar är härledt och den övergripande systemdesignen förklaras. I denna rapport förklaras vidare begreppen autonom banplanering följd av en introduktion till Robot Operating System (ROS) och dess tillämpning för systemplanering av systemet. Rapporten avslutas med en detaljerad analys av fördelarna med att använda detta tillvägagångssätt för att utveckla ett system. Det identifierar också bristerna för att tillämpa MBSE på systemutveckling. Rapporten stänger med en omtale om hur det givna projektet kan vidarebefordras för att kunna realisera det på ett fysiskt system.
37

Using model-based methods to support vehicle analysis planning

Bailey, William 13 January 2014 (has links)
Vehicle system analysis models are becoming crucial to automotive designers wishing to better understand vehicle-level attributes and how they vary under different operating conditions. Such models require substantial planning and collaboration between multidisciplinary engineering teams. To improve the process used to create a vehicle system analysis model, the broader question of how to plan and develop any model should be addressed. Model-Based Systems Engineering (MBSE) is one approach that can be used to make such complex engineering tasks more efficient. MBSE can improve these tasks in several ways. It allows for more formal communication among stakeholders, avoids the ambiguity commonly found in document-based approaches to systems engineering, and allows stakeholders to all contribute to a single, integrated system model. Commonly, the Systems Modeling Language (SysML) is used to integrate existing analysis models with a system-level SysML model. This thesis, on the other hand, focuses on using MBSE to support the planning and development of the analysis models themselves. This thesis proposes an MBSE approach to improve the development of system models for Integrated Vehicle Analysis (IVA). There are several contributions of this approach. A formal process is proposed that can be used to plan and develop system analysis models. A comprehensive SysML model is used to capture both a descriptive model of a Vehicle Reference Architecture (VRA), as well as the requirements, specifications, and documentation needed to plan and develop vehicle system analysis models. The development of both the process and SysML model was performed alongside Ford engineers to investigate how their current practices can be improved. For the process and SysML model to be implemented effectively, a set of software tools is used to create a more intuitive user interface for the stakeholders involved. First, functionality is added to views and viewpoints in SysML so that they may be used to formally capture the concerns of different stakeholders as exportable XML files. Using these stakeholder-specific XML files, a custom template engine can be used to generate unique spreadsheets for each stakeholder. In this way, the concerns and responsibilities of each stakeholder can be defined within the context of a formally defined process. The capability of these two tools is illustrated through the use of examples which mimic current practices at Ford and can demonstrate the utility of such an approach.
38

Manufacturing compliance analysis for architectural design: a knowledge-aided feature-based modeling framework

Valdes, Francisco Javier 27 May 2016 (has links)
Given that achieving nominal (all dimensions are theoretically perfect) geometry is challenging during building construction, understanding and anticipating sources of geometric variation through tolerances modeling and allocation is critical. However, existing building modeling environments lack the ability to support coordinated, incremental and systematic specification of manufacturing and construction requirements. This issue becomes evident when adding multi-material systems produced off site by different vendors during building erection. Current practices to improve this situation include costly and time-consuming operations that challenge the relationship among the stakeholders of a project. As one means to overcome this issue, this research proposes the development of a knowledge-aided modeling framework that integrates a parametric CAD tool with a system modeling application to assess variability in building construction. The CAD tool provides robust geometric modeling capabilities, while System Modeling allows for the specification of feature-based manufacturing requirements aligned with construction standards and construction processes know-how. The system facilitates the identification of conflicting interactions between tolerances and manufacturing specifications of building material systems. The expected contributions of this project are the representation of manufacturing knowledge and tolerances interaction across off-site building subsystems to identify conflicting manufacturing requirements and minimize costly construction errors. The proposed approach will store and allocate manufacturing knowledge as Model-Based Systems Engineering (MBSE) design specifications for both single and multiple material systems. Also, as new techniques in building design and construction are beginning to overlap with engineering methods and standards (e.g. in-factory prefabrication), this project seeks to create collaborative scenarios between MBSE and Building Information Modeling (BIM) based on parametric, simultaneous, software integration to reduce human-to-data translation errors, improving model consistency among domains. Important sub-stages of this project include the comprehensive review of modeling and allocation of tolerances and geometric deviations in design, construction and engineering; an approach for model integration among System Engineering models, mathematical engines and BIM (CAD) models; and finally, a demonstration computational implementation of a System-level tolerances modeling and allocation approach.
39

Model-Based Systems Engineering in Mobile Applications

Koch, Oliver, Weber, Jürgen 03 May 2016 (has links) (PDF)
An efficient system development needs reuse, traceability and understanding. Today, specifications are usually written in text documents. Reuse means a copy and paste of suitable specifications. Traceability is the textual note that references to affected requirements. Achieving a full context understanding requires reading hundreds of pages in a variety of documents. Changing one textual requirement in complex systems can be very time-consuming. Model-based systems engineering (MBSE) addresses these issues. There, an integrated system model is used for the design, analysis, communication and system specification and shall contribute to handling the system complexity. This paper shows aspects of this approach in the development of a wheel loader\'s attachment system. Customer requirements will be used to derive a specification model. Based on this, the author introduces the system and software architecture. The connection between requirement and architecture leads to a traceable system design and produces the huge advantage of MBSE.
40

Applying systems modeling and case study methodologies to develop building information modeling for masonry construction

Lee, Bryan 08 June 2015 (has links)
Building Information Modeling, or BIM, is a digital representation of physical and functional characteristics of a facility that serves as a shared resource for information for decision-making throughout the project lifecycle (National Institute of Building Sciences, 2007). The masonry construction industry currently suffers from the lack of BIM integration. Where other industries and trades have increased productivity by implementing standards for software-enhanced workflows, masonry construction has failed to adopt information tools and processes. New information technology and process modeling tools have grown in popularity and their use is helping to understand and improve construction processes. The Systems Modeling Language, or SysML, is one of the process modeling tools we can use to model and analyze the various processes and workflows. In this research, a case study methodology was applied to analyze the masonry construction industry to understand the current state of masonry construction processes and workflows. This thesis reviews these concepts and the applied case studies which are necessary to move forward with the implementation of BIM for masonry.

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