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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.
11

A simulation-driven model-based approach for designing software-intensive systems-of-systems architectures / Uma abordagem digirida por simulação e baseada em modelos para projeto de arquiteturas de sistemas de sistemas intensivos em software

Valdemar Vicente Graciano Neto 27 March 2018 (has links)
Context: Software-intensive systems have been increasingly interoperated forming alliances termed as Systems-of-Systems (SoS). SoS comprises a collection of systems joined to achieve a set of missions that none of the systems can accomplish on its own. Each constituent system keeps its own management, goals, and resources while coordinating within the SoS and adapting to meet SoS goals. Applications of SoS range from traffic control to emergency response and crisis management. As SoS often support critical domains, such systems must be correct by dealing with malfunction or defects and avoiding failures that could cause extensive damage and losses to the users. Problem: Correct SoS operations depend on a precise specification and a rigorous attestation of its operational consistency. However, besides limitations on languages to jointly capture SoS structure and behavior, predictions on the SoS operational consistency rely on constituent systems not totally known at design-time. Therefore, SoS have been developed and deployed without evaluating their operations, since current languages do not support such precision in evaluation. Objectives: This thesis provides solutions founded on a formal architectural description language to support an early evaluation of SoS operation regarding SoS structure and behavior by means of simulations. Contribution: The main contributions of this project comprise (i) a model transformation approach for automatically producing simulation models from SoS software architecture descriptions, combining SoS structure and behavior description in a same solution, (ii) a SoS software architecture evaluation method for SoS operation prediction considering the inherent changes that can occur, (iii) environment modelling and automatic generation of stimuli generators to sustain the SoS simulation, delivering data to feed such simulation, and (iv) a method for the automatic synchronization between the runtime descriptive architecture (changed at runtime due to dynamic architecture) and its original prescriptive architecture based on model discovery and recovery mechanisms and a backward model transformation. Evaluation: We conducted case studies to assess our solutions using Flood Monitoring SoS and Space SoS. Results: Our solutions support a high accuracy to (i) produce fault-free and fully operational simulations for SoS software architectures, (ii) support evaluation and prediction of SoS operation at design-time, (iii) automatically generate stimuli generators to sustain and feed the simulation execution, and (iv) maintain the synchronization between the runtime architecture and the intended version of the SoS architecture. Conclusions: We concluded that the proposed solutions advance the state of the art in SoS software architecture evaluation by offering solutions to predict the SoS operations effectiveness to maintain a continuous operation despite architectural changes, providing more trust for users that futurely shall rely on SoS services. / Contexto: Sistemas intensivos em software tem sido interoperados para formar alianças conhecidas como Sistemas-de-Sistemas (SoS). Domínios de aplicação de SoS variam do controle de tráfego ao gerenciamento de situações de crises e emergência. Devido à criticidade destes domínios, tais sistemas precisam ser confiáveis e robustos, lidando com potenciais defeitos e mal funcionamento, e evitando falhas que poderiam causar ameaças à integridade dos usuários. Problema: O funcionamento correto de um SoS depende da especificação precisa e da garantia rigorosa da consistência de suas operações. Entretanto, além das limitações nas linguagens quanto à especificação de ambos estrutura e comportamento do SoS, prever seu comportamento depende da especificação de constituintes que não são totalmente conhecidos em tempo de projeto e de seu comportamento emergente. Neste sentido, SoS têm sido desenvolvidos e implantados sem a devida avaliação de seus comportamentos, uma vez que as linguagens disponíveis atualmente não dão suporte a uma especificação precisa destes comportamentos. Objetivos: Este projeto de doutorado relata avanços teóricos e práticos fundamentados em uma linguagem de descrição arquitetural formal para permitir a predição e avaliação do comportamento e estrutura dos SoS com base em simulações. Contribuições: As principais contribuições deste projeto envolvem (i) uma transformação de modelos para produzir automaticamente modelos de simulação para descrições de arquitetura de software de SoS, combinando estrutura e comportamento em uma mesma solução, (ii) um método de avaliação de arquitetura de software de SoS para prever o comportamento do SoS considerando sua dinâmica inerente, (iii) modelagem do ambiente e derivação automática de geradores de estímulos entregando dados continuamente e sustentando a execução de simulações de SoS, e (iv) um método para promover a sincronização automática entre modelos descritivos e prescritivos de arquitetura de software de SoS baseados em mecanismos de descoberta e recuperação de modelos, e transformação de modelos reversa. Avaliação: Estudos de caso foram conduzidos para avaliar as soluções nos domínios de Monitoramento de Enchentes e Espacial. Resultados: As abordagens propostas exibem alta acurácia no que tange (i) a produzir simulações operacionais e sem falhas para arquiteturas de software de SoS, (ii) ao suporte á avaliação, ainda em tempo de projeto, do comportamento que emerge da operação do SoS, (iii) à derivação automática de geradores de estímulos para entrega contínua de dados e manutenção da execução das simulações geradas, e (iv) à manutenção do alinhamento entre os modelos descritivos e prescritivos da arquitetura do SoS avaliado. Conclusões: Conclui-se que as abordagens propostas avançam o estado da arte no projeto de arquiteturas de Software de SoS ao permitir prever, em tempo de projeto, como o SoS vai operar em tempo de execução, permitindo estabelecer estratégias para manter a simulação rodando, e sua operação contínua, mesmo com as mudanças arquiteturais inerentes ao seu funcionamento, provendo mais confiabilidade para os usuários futuramente dependerão de seus serviços.
12

Subsystem Failure Analysis Within the Horizon Simulation Framework

Lunsford, Ian M 01 June 2016 (has links) (PDF)
System design is an inherently expensive and time consuming process. Engineers are constantly tasked to investigate new solutions for various programs. Model-based systems engineering (MBSE) is an up and coming successful method used to reduce the time spent during the design process. By utilizing simulations, model-based systems engineering can verify high-level system requirements quickly and at low cost early in the design process. The Horizon Simulation Framework, or HSF, provides the capability of simulating a system and verifying the system performance. This paper outlines an improvement to the Horizon Simulation Framework by providing information to the user regarding schedule failures due to subsystem failures and constraint violations. Using the C# language, constraint violation rates and subsystem failure rates are organized by magnitude and written to .csv files. Also, proper subsystem failure and constraint violation checking orders were stored for HSF to use as new evaluation sequences. The functionalities of the systemEval framework were verified by five test cases. The output information can be used for the user to improve their system and possibly reduce the total run-time of the Horizon Simulation Framework.
13

ORQA : un canevas logiciel pour la gestion de l'énergie dans les véhicules électriques / ORQA : a framework for the energy management in electric vehicles

Christophe-Tchakaloff, Borjan 13 January 2015 (has links)
Les véhicules électriques présentent désormais une alternative crédible aux véhicules équipés demoteurs à combustion interne. Ils sont plus propres et plus confortables à l’utilisation. La gestion del’énergie d’un véhicule électrique est actuellement focalisée sur le fonctionnement du moteur, principalconsommateur d’énergie, sans tenir compte du confort de l’utilisateur.Le travail présenté dans cette thèse intègre la prise en compte des préférences utilisateur au seinde la gestion de l’énergie des véhicules électriques. La contribution est réalisée par un canevas logicielnommé ORQA. Dans un premier temps, les organes du véhicule sont caractérisés par leurs besoinsénergétiques et par les niveaux de qualité de service qu’ils proposent. Un gestionnaire d’énergie estensuite intégré au système logiciel du véhicule. Il se base sur les caractéristiques des organes et propose àl’utilisateur une solution de configuration de trajet prenant en compte ses préférences d’utilisation ainsique d’éventuelles contraintes de temps et d’énergie. Cette solution définit des contraintes d’utilisationsur le moteur et les organes de confort lors du déroulement du trajet.Le gestionnaire d’énergie est exécuté au sein des systèmes embarqués du véhicule dont les platesformessont fortement contraintes. Pour satisfaire celles-ci, il est primordial de proposer une configurationefficace du gestionnaire d’énergie. L’intérêt et la validité de l’approche employée sont démontrésau travers de la comparaison entre la configuration originelle et une configuration optimisée sur deuxvéhicules exemples. / Electric vehicles are nowadays a viable alternative to vehicles built around an internal combustionengine. They offer a cleaner and more comfortable driving thanks to the electric engine. The energymanagement of an electric vehicle is usually focused on the engine operation, the biggest energyconsumer, thus ignoring the user comfort.The contribution presented in this thesis allows for the consideration of the user preferences insidethe energy management of electric vehicles. It takes shape with a framework named ORQA. First,the vehicle devices are characterised by their energy requirements and the quality levels they offer.An energy manager based on the devices characteristics is then integrated into the software systemof the vehicle. The manager offers the user a solution to configure a trip request. The configuration isbased on the usage preferences and optional constraints over duration and consumption. The solutiondefines a set of constraints on the motor and on the comfort-related devices during the trip execution.The energy manager is executed in the embedded systems of the vehicle which platforms are highlyconstrained. Thus, the energy manager’s implementation is optimised to satisfy the execution platformconstraints. The interest and the validity of the chosen approach are attested by the comparison ofthe original configuration and an optimised configuration on two example vehicles.
14

De la conception de produit à la conception de filière : Quelles méthodologies pour les étapes amont de l’innovation ? / From product design to supply chain design : Which methodologies for the upstream stages of innovation?

Marche, Brunelle 22 November 2018 (has links)
Ce travail contribue à la recherche scientifique à travers différents aspects. Tout d’abord, le couple produit/filière, traditionnellement pensé de façon causaliste, a été envisagé à travers le prisme du paradigme de la complexité. Cette contribution théorique souligne la nécessité de co-concevoir le couple produit/filière afin d’atténuer les efforts associés au lancement d’un produit innovant sur le marché et de s’assurer de son succès. Cependant, une étude empirique a souligné que peu d’entreprises tenaient compte de la filière lors de la conception de leur produit innovant. Dans ce contexte, une ingénierie de conception de filière a été élaborée en se basant sur les données de conception du produit afin de concevoir, spécifier, valider et mettre en œuvre la filière d’un nouveau produit. Cette ingénierie se décompose en trois étapes majeures : une étape de co-conception, une étape de positionnement et une étape d’évaluation. L’étape de co-conception vise à collecter et à traiter les données de conception du produit fournies par l’équipe projet. Un modèle instancié de la filière a été développé afin de collecter les données nécessaires à la conception de la filière qui sont ensuite traités pour faciliter la modélisation. L’étape de positionnement vise à souligner le rôle de l’entreprise innovante au sein des différents scénarios de filière obtenus. Basée sur le processus Harmony for System Engineering et son outil Rational Rhapsody®, cette étape détaille la filière d’un point de vue exigences, acteurs, processus et comportement (chacun représenté par différents diagrammes) afin d’élaborer différents scenarios. Enfin, la dernière étape vise à évaluer ces scénarios de filière afin d’établir une stratégie cohérente. En effet, de nombreux chercheurs ont montré qu’une filière agile était plus apte à supporter un produit innovant lors de son lancement afin de s’adapter plus rapidement aux changements (organisationnels, tactiques, marketing, environnementaux…). Par conséquent, une trame basée sur des phénomènes observables a été développée afin de faciliter la mise en œuvre de stratégie d’agilité, ce qui permet d’évaluer la typologie de la filière actuelle et de décider des actions à mettre en place pour obtenir une filière plus agile. Cette ingénierie a été testée auprès d’entreprises manufacturières / This thesis contributes to scientific research through different aspects. First of all, the product/supply chain couple, traditionally thought of in a causalistic way, was considered through the prism of the complexity paradigm. This theoretical contribution underlines the need to co-design the product/supply chain couple in order to mitigate the efforts associated with launching an innovative product on the market and to ensure its success. However, an empirical study has pointed out that few companies consider the supply chain when designing their innovative product. In this context, supply chain design engineering was developed based on product design data in order to design, specify, validate and implement the supply chain of a new product. This engineering is divided into three major stages: a co-design stage, a positioning stage and an evaluation stage. The co-design stage aims to collect and process the product design data provided by the project team. An instantiated supply chain model was developed to collect the data needed to design the supply chain which is then processed to facilitate modeling. The positioning stage aims to highlight the role of the innovative company within the various supply chain scenarios obtained. Based on the Harmony for System Engineering process and its Rational Rhapsody® tool, this step details the supply chain from a point of view of requirements, stakeholders, processes and behavior (each represented by different diagrams) in order to elaborate different scenarios. Finally, the last step aims to evaluate these supply chain scenarios in order to establish a coherent strategy. Indeed, many researchers have shown that an agile supply chain is better able to support an innovative product when it is launched in order to adapt more quickly to changes (organizational, tactical, marketing, environmental…). Consequently, a framework based on observable phenomena has been developed to facilitate the implementation of an agility strategy, which makes it possible to evaluate the typology of the current supply chain and decide which actions to implement to obtain a more agile supply chain. This engineering has been tested with manufacturing companies
15

MODEL-BASED SIMULATION OF AUTOMOTIVE SOFTWARE SYSTEMS

Kozhakenov, Temirzhan January 2020 (has links)
The car is the most common vehicle in the world. Millions of cars are produced annually. In order for each car to find its buyer, car companies are forced to constantly improve the design of the car. Modern models are emerging, new car systems are being developed and implemented. All this is accompanied by a huge flow of information, in which it is easy to get lost. This master’s work is devoted to the trace analysis and connection of two different files. The paper proposes a developed algorithm of trace analysis for some functions of the vehicle in the C++ programming language. The files that we use to trace analysis relate to the model and the final result of its simulation.EATOP is a tool with which a model based on the EAST-ADL language was developed. Adapt is an event simulator with which our model of automotive functionality was simulated. The purpose of the study is to identify possible ways to meet timing requirements. The work is carried out in collaboration with Volvo Group Truck Technology. This company provided the LogFile, which presents results of the simulation, and model. We get an analysis of performance, one of the ways to trace data and timing. The results of our implementation are presented and discussed.
16

Model based engineering for electro-hydraulic solutions

Wahler, Matthias, Sendelbach, Thomas 26 June 2020 (has links)
This paper will give an overview about the technological change in Industrial Hydraulics and the impact of the Digital Twin on the related new engineering processes and methods in order to overcome the challenges coming out of that technology change. Simulation models will more and more become a decisive factor for the engineering process. The Digital Twin will be a window of opportunity for innovations and a technology push for the engineering process and the products in the Industrial Hydraulics.
17

Modélisation et optimisation des systèmes complexes en conception innovante : application aux chaines de transmission hybrides / Modelling and optimization approach for the design complex systems in innovation : case study applied to hybrid powertrain system

Ben beldi, Nesrine 02 September 2015 (has links)
Dans un contexte industriel qui évolue rapidement et constamment, les constructeurs automobiles sont amenés à développer des produits qui soient en adéquation avec des demandes d'un marché international et qui respectent en même temps les contraintes réglementaires imposées. Les systèmes de chaine de transmission hybrides rentrent donc dans cette volonté des constructeurs à vouloir proposer des produits véhicules performants, à faible coût et respectant les contraintes d'émission de gaz polluants. A travers le travail effectué dans cette thèse, nous proposons une démarche de conception permettant de modéliser un système technique complexe à différents niveaux systémiques au cours du cycle de conception, de l'optimiser localement à partir des expertises métiers, de modéliser les connaissances collaboratives qui sont échangées entre les modèles métiers et d'optimiser l'espace de conception afin de converger vers une solution de conception optimale dans un contexte d'innovation ou nous partons de la feuille blanche.L'objectif de ce travail est de proposer une nouvelle façon d'aborder les problèmes de conception des systèmes complexes, qui s'adapte au contexte de conception innovante tout comme la conception routinière. Ceci afin de permettre aux entreprises telles que PSA Peugeot Citroën de pouvoir proposer des produits avec des technologies à forte rupture tout en réduisant leurs coûts et garantir leurs images de marque. Ce travail a été illustré et validé à travers les résultats obtenus dans le cadre du projet de conception de chaine de transmission hybride MTI effectué au département d'innovation de PSA Peugeot Citroën. / In an industrial context that is continuously evolving and changing, automotive constructors find themselves obliged to develop their products by taking into account the requirements of an international market and the imposed regulations in this field. Hybrid powertrain systems fits into this constructor will to propose to customers efficient products that respects the regulation regarding gas emissions and presents a profitable low cost. Through the work done in this PhD, we propose a design approach that allow the modeling of a complex technical system in its different systemic levels during the design process, the local optimization done from professional expertise, the modeling of collaborative data exchanged between expert models and the optimization of the design space in order to converge towards an optimal design solution in innovative context.The aim of our work is to propose a new way of dealing with design problems related to complex systems that can be adapted to an innovative design context. This will allow companies such as PSA Peugeot Citroen to be able to diversify their products and integrated even the latest technology in it. This work has been illustrated and validated through the results obtained on the MTI project for the design of hybrid powertrain.
18

Plateforme autonomique dirigée par les modèles pour la construction d'interfaces multimodales dans les environnements pervasifs / Model-Driven Autonomic Framework for Building Multimodal Interfaces in Pervasive Environments

Avouac, Pierre-Alain 07 February 2013 (has links)
La construction d’interfaces homme-machine au dessus d’applications complexes soulève aujourd’hui des problèmes importants et requiert des efforts de recherche conséquents et soutenus. Il s’agit en effet d’aborder des technologies de plus en plus diverses et complexes de façon à construire des interfaces modulaires, évolutives et tirant profits des récents progrès dans les domaines de la programmation et des intergiciels. Il s’agit également de permettre à des non informaticiens, spécialistes de l’ergonomie, de définir et de mettre en place des interfaces appropriées. L’approche orientée service (Service-oriented Computing - SOC) constitue une avancée récente en Génie Logiciel. Cette approche promeut la mise en place de solutions modulaires et dynamiques permettant de faire évoluer, possiblement à l’exécution, les interfaces. L’approche orientée service est très prometteuse et de nombreux projets de recherche sont en cours dans les domaines de l’intégration d’entreprise, des équipements mobiles ou encore de l’informatique pervasive. L’approche orientée service demeure néanmoins complexe et demande un haut niveau d’expertise. Elle est difficilement accessible par des informaticiens non formés et totalement hors de portée des ingénieurs d’autres métiers, ergonomes par exemple. L’approche proposée dans cette thèse est de construire un atelier manipulant des services IHM abstraits. Ces services abstraits décrivent leurs fonctionnalités et leurs dépendances à un haut niveau d’abstraction. Ils peuvent ainsi être composés de façon plus aisée par des ingénieurs non experts en SOC. Le rôle de l’atelier est ensuite d’identifier des services concrets, implantant les services abstraits, de les composer en générant le code nécessaire (glue code) et de les déployer sur une plate-forme d’exécution. Un deuxième point concerne la spécialisation de l’atelier. Il est effet important de proposer un langage de composition de services proches des concepts métiers manipulés par les experts, notamment les ergonomes. Un tel langage se base sur les concepts métiers et intègre les contraintes de composition propres au domaine. L’approche actuelle passe par l’utilisation de méta-modèles, exprimant les connaissances métier, pour la spécialisation de l’atelier. / N pervasive environments, with the proliferation of communicating devices in the environments (e.g., remoter controller, gamepad, mobile phone, augmented object), the users will express their needs or desires to an enormous variety of services with a multitude of available interaction modalities, expecting concurrently the environment and its equipment to react accordingly. Addressing the challenge of dynamic management at runtime of multimodal interaction in pervasive environments, our contribution is dedicated to software engineering of dynamic multimodal interfaces by providing: a specification language for multimodal interaction, an autonomic manager and an integration platform. The autonomic manager uses models to generate and maintain a multimodal interaction adapted to the current conditions of the environment. The multimodal interaction data-flow from input devices to a service is then effectively realized by the integration platform. Our conceptual solution is implemented by our DynaMo platform that is fully operational and stable. DynaMo is based on iPOJO, a dynamic service-oriented component framework built on top of OSGi and on Cilia, a component-based mediation framework.
19

DIGITAL TWIN: FACTORY DISCRETE EVENT SIMULATION

Zachary Brooks Smith (7659032) 04 November 2019 (has links)
Industrial revolutions bring dynamic change to industry through major technological advances (Freeman & Louca, 2002). People and companies must take advantage of industrial revolutions in order to reap its benefits (Bruland & Smith, 2013). Currently, the 4th industrial revolution, industry is transforming advanced manufacturing and engineering capabilities through digital transformation. Company X’s production system was investigated in the research. Detailed evaluation the production process revealed bottlenecks and inefficiency (Melton, 2005). Using the Digital Twin and Discrete Event Factory Simulation, the researcher gathered factory and production input data to simulate the process and provide a system level, holistic view of Company X’s production system to show how factory simulation enables process improvement. The National Academy of Engineering supports Discrete Event Factory Simulation as advancing Personalized Learning through its ability to meet the unique problem solving needs of engineering and manufacturing process through advanced simulation technology (National Academy of Engineering, 2018). The directed project applied two process optimization experiments to the production system through the simulation tool, 3DExperience wiht the DELMIA application from Dassualt Systemes (Dassault, 2018). The experiment resulted in a 10% improvement in production time and a 10% reduction in labor costs due to the optimization

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