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Pykal, Vojtěch. "Výpočtové modelování dynamiky záběru čelního ozubeného soukolí v prostředí MBS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-445163.
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This master’s thesis is focused on the compilation of a computational modelling of gear mesh engagement dynamics of a spur gear by MBS approach. The user input is the specific geometry of gears, the operating speed, and the load torque. The output are the forces in the gear engagement and the reaction of the forces in the wheel bearings depending on the change in the stiffness of the gear due to the changing number of teeth in the engagement and the change in the axial distance. This model is characterized by a fast and relatively accurate calculation in the time domain. This means that it can react to changes in parameters during simulation such as axial distance, speed, and torque.
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Mallikarjuna, Rao Tarun. "Modelling and simulation of Research Concept Vehicle using MBD-FEM approach." Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183008.
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This work highlights the design process to build a MBD (Multi-Body Dynamics) model with flexible parts for a RCV (Research Concept Vehicle). Full vehicle dynamic simulations of the RCV model with flexible parts were performed for different load cases and the results were compared with that of a MBD model with rigid body components. In addition, FE modelling of the RCV body parts, selection of attachment nodes, generation and verification of Modal Neutral Files (MNFs) are discussed. RCV is a concept vehicle developed at KTH Royal Institute of technology as a research platform to implement, validate and demonstrate results of various research projects. The vehicle consists of body, suspension and tire subsystems which were designed and developed as individual projects. The body subsystem comprises of rollcage, subframe and a composite baseplate. In this project, a MBD model of the RCV was developed in ADAMS/CAR to measure the forces acting at the interface of these body components and also to consider the suspension forces acting on the individual front and rear subframe parts. Finite element (FE) models were incorporated to consider the flexibility of the body components. The RCV is a vehicle constantly evolving with addition of new components to implement and test various research results. To study the application of this method, two Models of the RCV with design modifications were developed and studied. A model of the RCV without rollcage and a model with a rigid link connecting the body components were built and the results of dynamic simulations were compared with that of the existing RCV design. When flexibility of the baseplate was considered in the models, an overall change in dynamics of the body components was observed. Further, observing the results from models with design modifications, it was evident that this method can be used to study the effect of these modifications on the dynamic behaviour of the vehicle.<br>Det här arbetet belyser konstruktionsprocessen för att bygga en MBD-modell (Multi-Body Dynamics) med flexibla komponenter av konceptfordonet RCV (Research Concept Vehicle). Fullständiga fordonsdynamiska simuleringar med flexibla komponenter utfördes för olika lastfall och resultaten jämfördes med en MBD-modell med stela komponenter. Dessutom diskuteras FE modellering av RCVs olika delsystem, val av kopplingsnoder, generering och verifiering av ”Modal Neutral Files” (MNFs). RCV är ett konceptfordon som utvecklats vid Kungliga Tekniska Högskolan, KTH, som en forskningsplattform för att implementera, validera och demonstrera resultaten av olika forskningsprojekt. Fordonet består av delsystemen; chassi, hjulupphängning, och däck, vilka har utvecklats tidigare i separata projekt. Chassit består i sin tur av delsystemen; ”rollcage”, ”subframe” och ”baseplate”. I detta projekt har en MBD-modell av RCV utvecklats i ADAMS/CAR för att simulera olika körfall och beräkna de krafter som verkar mellan dessa delsystem och att också studera skillnaden i belastning av främre resp. bakre ”subframe”. FE modeller importeradesäven till modellen för att studera effekten av elasticiteten hos komponenterna på fordonets beteende.RVC är ett fordon som konstant utvecklas med tillägg av nya komponenter för att implementera och testa olika forskningsresultat. För att studera tillämpningen av denna metod skapades två modeller av RCV med olika konstruktiva förändringar vilkas inverkan på fordonet studerades. En modell av RCV utan ”rollcage” och en modell med styv länk som förbinder olika delar av chassit skapades och resultaten av dynamiska simuleringar jämfördes med simuleringsresultat för den befintliga RCV-designen. När flexibiliteten hos basplattan beaktades i modellerna observerades förändringar i dynamiken hos chassit vad gäller vertikala förskjutningar och vinkelförskjutningar. Utifrån dessa simuleringar kan vi dra slutsatsen att den utvecklade metoden är användbar för att studera effekter av konstruktionsförändringar på det dynamiska beteendet hos fordonet.
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Roa, castro Laura. "Management de la complexité organisationnelle des projets en ingénierie systèmes : Mise en place d'une approche socio-technique pour l'amélioration des aspects collaboratifs." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLC023/document.
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Du fait du développement de nouveaux produits (NPD) dans l’industrie, l’organisation devient de plus en plus complexe, ceci est dû notamment à la complexité même des produits. Dans ce contexte, le MBSE (Model Based Systems Engineering) et les approches collaboratives, qui adressent ces complexités, ont été reconnus pour leurs facultés à améliorer le NPD. Une implémentation réussie d’une conception collaborative du type MBSE, doit permettre de gérer ces deux complexités. Cette thèse de doctorat a pour objet l’étude de projets de conception collaborative MBSE au sein des équipes françaises chez des équipementiers automobiles et aéronautiques, afin de mettre en avant l’amélioration du développement des produits. La conception collaborative du type MBSE est assimilable à un système organisationnel complexe, impliquant des vues ou dimensions différentes. Ainsi, l’identification de ces dimensions, leur définition et l’étude de leurs interactions constituent le premier objectif de cette recherche. La compréhension de chacune d’entre elles pour améliorer la collaboration entre les différents membres du projet, est le deuxième objectif.Le troisième et dernier objectif de cette thèse est de proposer des systèmes socio-techniques (STS), assistant la collaboration. Les résultats de cette recherche, fournissent une méthodologie pour manager la complexité organisationnelle dans des projets collaboratifs du type MBSE. Elle est le produit d’une combinaison de quatre méthodes permettant la caractérisation de ses dimensions (processus, acteurs, objets et outils), tout en définissant leurs interactions. Ces méthodes assistent respectivement : 1) La description et l’évaluation de ces projets avec une perspective systémique 2) l’établissement d’une vision partagée du travail 3) l’analyse des coopérations entre les acteurs, et 4) le développement de STS tels quels des environnements collaboratifs et des supports collaboratif de capitalisation. L’implémentation en industrie des méthodes proposées, processus et recommandations, a montré comment la mise en avant de la collaboration dans les projets de design MBSE, permet d’améliorer l’ensemble du développement de produit<br>The organisational complexity implied by New Product Development (NPD) within the industry, is often induced by the complex nature of the products themselves. In this context, MBSE (Model Based Systems Engineering) and collaborative approaches address those complexities and have been recognised by their contribution to improve the NPD processes. A successful implementation of a collaborative MBSE design would allow to manage both complexities. This PhD thesis describes an investigation on collaborative MBSE design projects within French teams in automotive and aeronautics companies, with the purpose of enhancing them to improve product development. We understand collaborative MBSE design as a complex organisational system which implies different views or dimensions. The identification of those dimensions, their definition and the study of their interactions constitute the first objective of this research. Understanding each dimension in order to improve collaboration between the project members is the second objectivedeuxième objectif.The third and last objective of this research is to propose Socio Technical Systems (STS) supporting this collaboration. The results of the thesis provide a methodology to manage organisational complexity in collaborative MBSE design projects. The methodology is a combination of four methods assisting the characterisation of the MBSE dimensions (people, process, information objects and tools), while defining their interactions. These methods support respectively: 1) The assessment and description of collaborative MBSE design projects from a systemic perspective 2) The establishment of a shared vision of the work 3) The analysis of the cooperation among the actors 4) The development of STS such as collaborative environment and a collaborative capitalisation support. The implementation of the proposed methods, process and guidelines in the industry has shown how the enhancement of collaboration in MBSE design projects can improve the overall product development
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Goumaa, Rasha. "Examining the nature of reflective learning in an online MBA : a dialogic approach." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/19513/.
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The debate around the relevance of management education to practice is a long standing one. Critics argue that conventional, lectured-based teaching does not attend to practitioners’ needs and their complex realities. Critical management education has been held up as an alternate teaching pedagogy that speaks more adequately to practice. A starting point for a critical pedagogy may be a social constructivist approach where students actively construct their own knowledge and meanings rather than passively receive information. The essence of critical management education is to create more spaces to promote a questioning attitude towards practice and theory and help management students to become active, reflective learners. So far, investigations of criticality seem to have largely drawn on exploring management students’ perspectives about their learning experience. Little evidence is available on what becoming more or less critical entails for management students from within practice. There is no mention of a rigorous framework that would offer insights about what to look for in investigating reflective learning from within its natural setting. As an area that appears to be under developed in critical management education research, the nature of reflective learning evoked in classroom dialogue is considered, and a framework is devised based on Bakhtin’s dialogism to help identify and conceptualize reflective learning. The availability of online courses has grown strongly over the past two decades. A number of commentators consequently see that online management learning is becoming a mainstream aspect of higher education. Yet, serious reservations against the nature of learning that an asynchronous, text-based learning environment can offer management students have been raised. Therefore, an online MBA classroom is chosen as the site of this study. Data is collected through a combination of observations of online classroom conversations and document analysis. The proposed framework is used is to carry out a relational analysis of online, text-based classroom conversations. It is not the asynchronicity of the setting that is inherently problematic in stimulating reflective, emancipatory learning. The potential of online management classrooms to engender dialogic, reflective learning amongst management students responds to the wider critiques of the status of learning in management classrooms. A critical approach to online teaching, which is not underpinned by a critical curriculum, is proposed. There is an urgent need to attend to the role of online tutors and their influence on the nature of learning, which occurs in their conversations with students in virtual classrooms. The study opens up the scope for assessing online management learning as a “dialogical construction of meaning” and offers insights into the online setting beyond the passive portrayals of learners.
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Abdeljabbar, Nourhene. "Conception d'une méthodologie appliquée aux modèles dynamiques multi-physiques à topologie dynamique." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC016.
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La modélisation des systèmes mécatroniques nécessite le même type de méthodologie pour la conception et le prototypage de dispositifs mécatroniques. Une ingénierie unifiée et intégrée doit être déployée. Diverses approches sont actuellement proposées pour atteindre de la modélisation multi-physique comme la théorie des graphes, les approches équationnelles ou les techniques. Dans ce contexte, l’objectif de nos travaux de recherche est la conception d'une méthodologie appliquée aux modèles dynamiques multi-physiques à topologie dynamique. Pour une telle contribution, il est nécessaire de partir d’une approche existante. Cette approche porte sur la modélisation topologique puisqu’elle est basée sur les collections topologiques et les transformations. Cette approche topologique est utilisée pour modéliser les systèmes mécatroniques.Son point fort est la séparation de la topologie (loi d'interconnexion) et la loi de comportement (physique) qui permet la simplification de la modélisation de systèmes complexes que l'on peut décrire comme un ensemble d'interactions locales entre entités élémentaires. La thèse propose donc une nouvelle méthodologie nommée 4Mo(DS)2 qui se rapporte à la modélisation multi-niveaux, multi-domaines et multi-physiques basée sur des systèmes dynamiques qui ont des structures dynamiques. Cette méthodologie permet la modélisation topologique des modèles dynamiques multi-physiques à topologie dynamique pendant la phase de conception tout en prenant en compte les modifications topologiques, le contrôle et commande ainsi que l’intégration de la dimension deux dans leur structure topologique<br>Mechatronic systems modelling requires the same type of methodology for the design and prototyping of mechatronic devices. Unified and integrated engineering must be deployed. Various approaches are currently proposed to achieve multi-physics modeling such as graph theory, equational approaches or techniques. In this context, the objective of our research work is the design of a methodology applied to dynamic multi-physical models with dynamic topology. For such a contribution, it is necessary to start from an existing approach. This approach focuses on topological modelling since it is based on topological collections and transformations. This topological approach is used to model mechatronic systems.Its strong point is the separation of topology (interconnection law) and behavior law (physical) which allows the simplification of the modeling of complex systems that can be described as a set of local interactions between elementary entities. The thesis therefore proposes a new methodology named 4Mo(DS)2 which relates to multilevel, multi-physical and multi-domain modeling based on dynamic systems that have dynamic structures. This methodology allows the topological modeling of dynamic multi-physical dynamic topology models during the design phase while taking into account topological modifications, control and command as well as the integration of dimension two into their topological structure
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McIntire, Mark Douglas. "Conformational studies of selected phosphines using an empirical computational approach." Virtual Press, 1985. http://liblink.bsu.edu/uhtbin/catkey/444702.
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Conformations of phenyl and alkyl substituted phosphines were studied by using an empirical computer program, CAMSEQ. The computer program employs potential energy functions for calculating non-bonded interactions. The three potential energy functions employed are: steric interactions, represented by Lennard-Jones 6-12 potentials; electrostatic interactions, computed from a Coulomb's Law function; and torsional barriers, approximated by a two-term cosine function. P-C and C-C torsional functions were parameterized for a variety of phosphorus and carbon substituents from published experimental data. Phenyl and alkyl substituent conformations as affected by length, Position and number of alkyl chain substituents are described and related to effective sizes of the phosphines.Ball State UniversityMuncie, IN 47306
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Hodgson, S. P. "A unified MCS based approach to the adaptive position and interaction control of robotic manipulators." Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357953.
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Gorman, C. Allen, and Thomas W. Moore. "Constructing Future Business Leaders:Evaluating a Mixed Methods Approach to Leadership Education in an MBA Curriculum." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/413.
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Gorman, C. Allen, and T. W. Moore. "Constructing Future Business Leaders: Evaluating a Mixed Methods Approach to Leadership Education in an MBA Curriculum." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/7787.
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Faye-Dumanget, Christine. "L'épuisement estudiantin : approche clinique, psychopathologique, épidémiologique et psychothérapeutique TCC du syndrome du burnout académique." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT2050/document.
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Dans le champ de la santé mentale, la population étudiante constitue un groupe particulièrement vulnérable en termes de détresse ou de souffrance psychologique. En effet, les risques anxiodépressifs et addictifs font partie des troubles souvent identifiés chez ces jeunes adultes. Le stress est également particulièrement prégnant et l’épuisement pour cette classe d’âge représente la première cause de fragilité psychologique. Les recherches internationales qui s’intéressent à la santé psychique des étudiants décrivent ce phénomène sous le terme de syndrome de burnout académique ou burnout académique (BOA). Cette souffrance largement reconnue dans le milieu professionnel est transposable au monde des études et de la formation. Elle reflète un processus tridimensionnel dont les composantes sont l’épuisement psychique, le cynisme et la réduction ou la perte du sentiment d’efficacité lié aux études. Si de nombreux travaux internationaux s’intéressent au BOA, il n’existe pas d’outil validé en français, ce qui complique la possibilité de mener de telles études systématisées dans des pays francophones. L’objectif de ce travail consiste à rendre compte du phénomène d’un point de vue clinique (cas cliniques), à valider empiriquement un outil d’évaluation du burnout académique (validation psychométrique du Maslach Burnout Inventory-Student Survey (MBI-SS) sur un échantillon de 667 étudiants), à procéder à l’exploration épidémiologique du BOA et ses les liens avec certains facteurs psychopathologiques (anxiété, dépression) et processus adaptatifs (régulation émotionnelle, flexibilité mentale) avec un échantillon de 2260 étudiants provenant d’espaces francophones et enfin à proposer une prise en charge du BOA s’appuyant sur les Thérapies Comportementales et Cognitives. L’ensemble de ces études est discuté afin de mettre en exergue la particularité du BOA dans cette population et la caractéristiques d’une dimension du BOA, l’épuisement émotionnel, en tant que processus transdiagnostique<br>The student population is a particularly vulnerable group in terms of distress or psychological suffering. Indeed, anxiety-depressive and addictive risks are often identified in these young adults. Stress is also particularly prevalent and exhaustion for this age group is the first leading cause of psychological fragility. International researches focusing on student psychic health refer to this phenomenon with the terms academic burnout syndrome or academic burnout (ABO). Burnout is widely recognized in professional environments and is transferable to other contexts, such as higher education and training. It reflects a three-dimensional process which includes mental exhaustion, cynicism and the reduction or loss of the sense of effectiveness associated with studies. Even if many international studies investigated ABO, no French validated tool is available, which complicates the possibility of conducting systematic studies in French-speaking countries. The objective of this work is to report on the phenomenon from a clinical point of view (clinical cases), to empirically validate an evaluation tool for academic burnout (psychometric validation of the Maslach Burnout Inventory Student Survey (MBI-SS) on a sample of 667 students), to carry out the epidemiological exploration of the ABO and its links with certain psychopathological factors (anxiety, depression) and adaptive processes ( emotional regulation, mental flexibility) with a sample of 2260 students from French-speaking areas and finally to propose a management of ABO based on Behavioral and Cognitive Therapies. All of these studies are discussed in order to highlight the particularity of the ABO in this population as well as the characteristics of one ABO dimension, the emotional exhaustion, as a transdiagnostic process
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Baduel, Ronan. "An integrated model-based early validation approach for railway systems." Thesis, Toulouse 2, 2019. http://www.theses.fr/2019TOU20083.
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L’ingénierie système est un domaine où l’on étudie la conception de systèmes complexes. Un système est une solution que l’on veut développer, par exemple un train ou un réseau de satellites. Un système complexe est composé de différents éléments indépendants. Les ingénieurs travaillent à partir de listes d’attentes vis à vis du système, chacune caractérisant ce qu’il doit être ou doit faire. Ils créent alors un système et vérifient qu’il répond aux attentes. Afin de gagner du temps et de l’argent, on souhaite vérifier que le système correspond aux attentes avant même de le réaliser. Cela demande d’intégrer les différentes attentes et spécifier comment elles doivent être mises ensembles, générant ainsi un système attendu que l’on peut valider. Le but de la thèse est de fournir une méthode permettant d'intégrer les informations caractérisant un système de train au cours de sa conception, permettant ainsi la spécification, la représentation et la validation de son comportement<br>System engineering is a domain that studies the conception of complex system. A system corresponds to a solution we want to develop, such as a train, a satellite network, etc. A complex system is composed of several independent elements Engineers work from lists of individual expectations regarding the system to be or what it is supposed to do, which they use to create a system and see if it answers expectations. To gain time and money, we would like to check that the system-to-be answers expectations before developing it: it requires to integrate expectations and specify how they should be put together, inducing a system expected that we can check. The goal pursued in this PhD is to provide a method to integrate information regarding a train system during conception, enabling the specification, representation and validation of its behavior
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Lundkvist, Herman, and Alexander Yngve. "Accelerated Simulation of Modelica Models Using an FPGA-Based Approach." Thesis, Linköpings universitet, Datorteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-145692.
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This thesis presents Monza, a system for accelerating the simulation of modelsof physical systems described by ordinary differential equations, using a generalpurpose computer with a PCIe FPGA expansion card. The system allows bothautomatic generation of an FPGA implementation from a model described in theModelica programming language, and simulation of said system.Monza accomplishes this by using a customizable hardware architecture forthe FPGA, consisting of a variable number of simple processing elements. A cus-tom compiler, also developed in this thesis, tailors and programs the architectureto run a specific model of a physical system.Testing was done on two test models, a water tank system and a Weibel-lung,with up to several thousand state variables. The resulting system is several timesfaster for smaller models and somewhat slower for larger models compared to aCPU. The conclusion is that the developed hardware architecture and softwaretoolchain is a feasible way of accelerating model execution, but more work isneeded to ensure faster execution at all times.
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Veeramani, Lekamani Sarangi. "Model Based Systems Engineering Approach to Autonomous Driving : Application of SysML for trajectory planning of autonomous vehicle." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254891.
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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.<br>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.
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Kerns, Corey Michael. "Naval Ship Design and Synthesis Model Architecture Using a Model-Based Systems Engineering Approach." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/32459.
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The Concept and Requirements Exploration process used at Virginia Tech is based on a Multi-Objective Optimization approach that explores the design space to produce a Non-Dominated set of ship design solutions ranked objectively by Cost, Risk, and Effectiveness. Prior research and effort has also been made to leverage the validation and verification of the U.S. Navyâ s ship synthesis design tool, ASSET, into the Virginia Tech Ship Synthesis Model.
This thesis applies Design Structure Matrix theory to analyze and optimize the ASSET synthesis process by reducing or removing the feedback dependencies that require the iterative convergence process. This optimized ASSET synthesis process is used as the basis to develop a new Simplified Ship Synthesis Model (SSSM) using Commercial Off-The-Shelf (COTS) software, ASSET Response Surface Models (RSMs) and simplified parametric equations to build the individual synthesis modules.
The current method of calculating an Overall Measure of Effectiveness (OMOE) used at Virginia Tech is based on expert opinion and pairwise comparison. This thesis researches methods for building a Design Reference Mission (DRM) composed of multiple operational situations (OpSits) required by the shipâ s mission. The DRM is defined using a Model Based Systems Engineering (MBSE) approach and an overall Ship Design System Architecture to define and understand the relationships between various aspects of the ship design. The system architecture includes the DRM and enables the development of Operational Effectiveness Models (OEMs) as an alternative to an expert opinion-based OMOE. The system architecture also provides the means for redefining and optimizing the entire ship design process by capturing the entire process and all related data into a single repository.
This thesis concludes with a preliminary assessment of the utility of these various system engineering tools to the naval ship design process.<br>Master of Science
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Borchani, Mohamed. "Approche d’ingénierie systèmes pour l’intégration de la fabricabilité dans le processus de conception des systèmes mécatroniques." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC043/document.
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L’originalité de notre travail consiste à développer une approche qui intègre l’ingénierie systèmes basée sur les modèles (MBSE) avec les principes de l’approche SBCE afin de réduire les boucles itératives entre les concepteurs inexpérimentés, les fabricants et les experts. D’autres parties prenantes participent également au développement du produit afin d’assurer environnement d’ingénierie simultanée. Cette approche offre un grand potentiel pour gérer les aspects de fabricabilité et de fiabilité, en raison de la capacité à développer des connaissances en parallèle, en particulier pour les technologies avancées et non matures. L’avantage d’utilisation des principes du SBCE est d’offrir des possibilités de communication entre les parties prenantes au début de la phase de conception. SysML est utilisé comme langage descriptif pour représenter les différentes phases de cette approche. Pour étudier la robustesse ces système, nous avons développé un modèle intitulé «Model Based for Robustness Analysis» (MBRA) qui a pour objectif de filtrer les solutions faibles ou coûteuses au fil du temps et d’assister l’ingénieur système lors de l'adoption d’une étude de compromis. Pour l’étude de la fabricabilité des systèmes complexes, nous avons développé un autre modèle intitulé « Model Based for Manufacturability analysis »<br>The originality of our work is to develop an approach that integrates model-based systems engineering (MBSE) with the principles of the SBCE approach to reduce iterative loops between inexperienced designers, manufacturers, and experts. Other stakeholders are also involved in product development to ensure simultaneous engineering environment. This approach offers great potential for managing manufacturability and reliability aspects, due to the ability to develop parallel knowledge, especially for advanced and non-mature technologies. The advantage of using SBCE principles is to provide opportunities for communication between stakeholders early in the design phase. SysML is used as a descriptive language to represent the different phases of this approach. To study the robustness of these systems, we have developed a model called "Model Based for Robustness Analysis" (MBRA) which aims to filter low or expensive solutions over time and to assist the system engineer when adopting a trade-offs study. For the assessment of the manufacturability of complex systems, we have developed another model entitled "Model Based for Manufacturability analysis"
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Carroll, Dustin W. "TARGETING THE CELLULAR REDOX ENVIRONMENT: A NOVEL APPROACH FOR THE TREATMENT OF HEMATOPOIETIC NEOPLASMS." UKnowledge, 2018. https://uknowledge.uky.edu/toxicology_etds/21.
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Hematopoietic stem cells (HSCs) that function to maintain the hematopoietic compartment through self-renewal and differentiation capacities, as well as their downstream progeny, are susceptible to transformation resulting in the generation of the leukemic stem cell (LSC). Chief in the factors that control HSC regulation and protection of the HSC compartment is the cellular redox environment. Deregulation of the Hematopoietic Stem/Progenitor Cell (HSPC) redox environment results in loss of HSPC function and exhaustion. The characteristic developments of HSPC exhaustion via exposure to redox stress closely mirror phenotypic traits of hematopoietic malignancies, presenting the HSPC/LSC redox environment as a potential therapeutic target. While myelosuppression and HSPC exhaustion are detrimental side effects of classical chemotherapies, new approaches that differentially modify the HSPC/LSC redox environment may demonstrate LSC cytotoxicity while offering protection of normal HSPC function via differential activation of internal signaling pathways. Precisely how the redox environment and downstream signaling events are affected by these treatments remains unclear; thus highlighting the need for robust methods that evaluate the HSPC/LSC redox state. Because the glutathione (GSH), glutathione disulfide (GSSG) redox couple heavily contributes to the management of HSPC function and redox environment, characterizing the GSH/GSSG redox potential at the HSPC level would provide great insight for therapeutic opportunities. However, accurate measurement the GSH/GSSG redox potential within HSPCs/LSCs has been difficult due to their inherently low numbers. Here, we describe the development and validation of a sensitive method used for the direct and simultaneous quantitation of both oxidized and reduced GSH via LC-MS/MS. We use these methodologies to establish a difference in GSH-GSSG half-cell reduction potentials between normal and malignant HSPCs and examine the therapeutic effect of a redox active MnSOD mimetic, Mn(III) mesotetrakis (N-n-butoxyethylpyridinium-2yl) porphyrin, MnTnBuOE-2-PyP5+ (MnP), within these populations in vitro as well as within a human xenograft model in vivo. MnP demonstrates significant cytotoxic effects in several malignant models, while inducing an opposite cytoprotective effect in normal HSPC populations. The GSH/GSSG redox balance, specifically managed by glutathione reductase activity, is identified as a determining factor of MnP efficacy in various malignant populations. Treatment of the human myelodysplastic cell line (MDSL) offers mechanistic insights into MnP efficacy through hydrogen peroxide mediated activation of activator protein 1 (AP-1) signaling. We identify the redox dependent activation of JunB, a known regulator of normal myeloid lineage HSC proliferation, as a transcriptional mechanistic mediator of MnP treatment induced AP-1 signaling resulting in malignant cytotoxicity. The development of this novel method allowing for the identification of targetable differences between normal and malignant cell populations has provided insight to the underpinnings of potential redox based therapies. Additionally, the finding that MnP can target varying cellular redox states and exert selective cytotoxicity in malignant over normal populations by re-gaining lost control of AP-1 signaling demonstrates the potential for development of safe therapeutics within a variety of clinical applications.
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Hjelmblom, Magnus. "Norm-Regulation of Agent Systems : Instrumentalizing an algebraic approach to agent system norms." Doctoral thesis, Stockholms universitet, Institutionen för data- och systemvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120602.
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An architecture for norm-regulated multi-agent systems based on an algebraic approach to normative systems is instrumentalized and further developed. The core of the instrumentalization is a Prolog module, which together with a Java library can be used for creating client/server-based runtime systems. Norms are represented as conditional sentences, whose normative consequences are formulated by applying normative operators to descriptive conditions. From such general normative conditions follow normative sentences regarding specific states of affairs. These in turn result in permission or prohibition of individual actions in specific situations. Furthermore, an approach to turning runtime systems into instruments for problem-solving by using evolutionary mechanisms for evolving normative systems, is presented. The construction of norm-creating operators on conditions, which forms the basis for the representation of normative systems, is approached from two angles. (i) A logical analysis based on the Kanger-Lindahl theory of normative positions is conducted. This results in two extended sets of types of normative positions, and based on an algebraic version of one of these extended systems, a set of operators for creating agent-specific norms is constructed. (ii) An alternative analysis, which takes as its starting point a systematic exploration of types of state transitions, yields a set of norm-creating operators based on prohibition of transition types. It is furthermore argued that in the context of a class of transition systems, in which transitions are deterministic and associated with a single agent performing an act, operators based on (ii) specify a meaningful semantics of operators based on (i). Theoretical results together with shared code and example applications contribute to make possible theoretically sound, transparently described, and efficiently implemented norm-regulated autonomous agent systems.<br>En arkitektur för normreglerade multiagentsystem baserad på en algebraisk representation av normativa system instrumentaliseras och vidareutvecklas. Kärnan i instrumentaliseringen utgörs av en Prolog-modul som tillsammans med ett Java-bibliotek kan användas för att skapa client/server-baserad körbar kod. Normer representeras som ordnade par av grundvillkor och följdvillkor. De senare konstrueras genom att normativa operatorer appliceras på deskriptiva villkor. Från sådana generella normativa villkor följer normativa satser om specifika sakförhållanden, vilka i sin tur ger upphov till förbud mot eller tillåtelse att utföra enskilda handlingar i olika situationer. Vidare skisseras en metod för att göra körbara multiagentsystem till verktyg för problemlösning genom att använda evolutionära mekanismer för att odla fram normativa system. Konstruktionen av normskapande operatorer på villkor, vilka ligger till grund för representationen av normativa system, betraktas ur två olika synvinklar. (i) En logisk analys, baserad på Kanger-Lindahls teori om normativa positioner. Denna resulterar i två utökade uppsättningar av typer av normativa positioner och utgående från en algebraisk version av ett av dessa utökade system konstrueras sedan en uppsättning operatorer för att skapa agentspecifika normer. (ii) En alternativ analys, som tar sin utgångspunkt i en systematisk undersökning av olika typer av tillståndsövergångar. Denna ger upphov till en uppsättning av normskapande operatorer som är baserade på förbud mot olika typer av övergångar. Argument presenteras vidare för att inom ramen för en klass av övergångssystem, där övergångar är deterministiska och associerade med en agent som utför en handling, så specificerar operatorer baserade på (ii) en meningsfull semantik för operatorer baserade på (i). Teoretiska resultat tillsammans med tillgängliggjord programkod och exempel på tillämpningar bidrar till att underlätta skapandet av teoretiskt sunda, transparent beskrivna och effektivt implementerade normreglerade system av autonoma agenter.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Submitted. Paper 5: Forthcoming.</p>
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Sellali, Brahim. "Intégration du retour d'expérience d'exploitation dans une approche MBF pour optimiser la fiabilité de matériel." Nancy 1, 1998. http://www.theses.fr/1998NAN10307.
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Dans cette étude nous avons proposé une méthodologie permettant de faciliter la mise en place d'un retour d'expérience évolutif et pertinent, élément essentiel dans la démarche maintenance basée sur la fiabilité (MBF). Cette démarche permet d'affiner le programme de maintenance, de mieux maîtriser les risques (arrêts de machines, pertes de productions) et de capitaliser de l'expérience pour l'avenir dans une logique qualité dans le secteur des PME/PMI. Les principes et les méthodes qui sous-tendent cette réalisation sont mis en évidence et la généralité de leur portée les rend directement transportables à d’autres tissus industriels. Pour valider cette démarche et mettre en exergue ses possibilités, nous avons développé pour le secteur des fonderies, un outil d'analyse des données d'exploitation par les méthodes appropriées facilitant la mise en place d'un Programme de Maintenance Optimisé (PMO) tenant compte de l'entreprise.
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Pastrana, John. "Model-Based Systems Engineering Approach to Distributed and Hybrid Simulation Systems." Doctoral diss., University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6336.
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INCOSE defines Model-Based Systems Engineering (MBSE) as "the formalized application of modeling to support system requirements, design, analysis, verification, and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases." One very important development is the utilization of MBSE to develop distributed and hybrid (discrete-continuous) simulation modeling systems. MBSE can help to describe the systems to be modeled and help make the right decisions and partitions to tame complexity.
The ability to embrace conceptual modeling and interoperability techniques during systems specification and design presents a great advantage in distributed and hybrid simulation systems development efforts. Our research is aimed at the definition of a methodological framework that uses MBSE languages, methods and tools for the development of these simulation systems. A model-based composition approach is defined at the initial steps to identify distributed systems interoperability requirements and hybrid simulation systems characteristics. Guidelines are developed to adopt simulation interoperability standards and conceptual modeling techniques using MBSE methods and tools. Domain specific system complexity and behavior can be captured with model-based approaches during the system architecture and functional design requirements definition. MBSE can allow simulation engineers to formally model different aspects of a problem ranging from architectures to corresponding behavioral analysis, to functional decompositions and user requirements (Jobe, 2008).<br>Ph.D.<br>Doctorate<br>Industrial Engineering and Management Systems<br>Engineering and Computer Science<br>Industrial Engineering
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Ammar, Randa. "Approche de co-développement pour l’intégration des modèles des produits mécatroniques avec les modèles des systèmes de production." Thesis, CY Cergy Paris Université, 2020. http://www.theses.fr/2020CYUN1107.
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Les produits d'ingénierie à l'ère de l'industrie 4.0 sont contraints d'être plus compacts, intelligents et efficaces. Les entreprises manufacturières sont aujourd'hui obligées d'adapter leurs systèmes de production avec des changements constants et inattendus dans les exigences des clients pour faire face à différents besoins et modes d'utilisation. Par conséquent, les contraintes de production doivent être intégrées dans les premières phases du processus de développement de systèmes complexes multidisciplinaires, et à la fois le produit et la gestion du système de production doivent être optimisés simultanément. Dans cette thèse, nous proposons une approche pour intégrer les contraintes de production au processus de conception du produit. Pour cela, les principes de l'approche Set-Based Concurrent Engineering (SBCE) sont mis en oeuvre en utilisant la méthode MBSE (Model-based System Engineering), afin de réduire les boucles d'échange itératives entre les acteurs de l'ingénierie. L'implémentation a été réalisée avec un prototype de framework logiciel utilisant le langage Python. Une étude de cas d'un boîtier-papillon électronique (ETB) a été utilisée pour illustrer et valider l'approche. L'analyse de l'étude de cas nous a permis de conclure que notre approche aide les concepteurs de systèmes complexes à intégrer les contraintes de production dans le processus de conception dès les phases préliminaires, et à prendre les bonnes décisions de conception pour éviter des investissements lourds liés au système de production<br>Engineered products in the era of Industry 4.0 are constrained to be more compact, smart and efficient. Manufacturing companies are today forced to adapt their production systems with constant and unexpected changes in the customer requirements to face different needs and user modes. Therefore, production constrains need to be integrated in the early phases of the development process of multidisciplinary complex systems, and both the product and the management of the production system should to be optimized concurrently. In this thesis, we propose an approach to integrate the production system constraints with the product design process. For this, the principles of the Set-Based Concurrent Engineering (SBCE) approach are implemented using the model-based system engineering (MBSE) method, in order to reduce the iterative exchange loops between engineering stakeholders. The implementation was performed in a software framework prototype using Python language. A case study of an Electronic Throttle Body (ETB) was used to illustrate and validate the approach. The analysis of the case study allowed us to conclude that our approach supports system designers to integrate production constraints in the early design process and make the right design decisions to avoid heavy investment in the production system
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Moones, Emna. "Proposition d'une approche méthodologique d'interopérabilité multi-niveaux dans un environnement de PLM collaboratif." Thesis, Paris 8, 2017. http://www.theses.fr/2017PA080093/document.
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Nos travaux de thèse concernent l’´étude de l’interopérabilité dans un environnement collaboratif et dynamique d’entreprise. Elle est considérée comme un facteur clé de collaboration qui doit être pris en compte tout au long du cycle de vie du produit. Ceci est particulièrement important en ce qui concerne les réseaux d'entreprise collaboratifs, tel que DMN, où un groupe distinct de partenaires est connecté dans un modèle en forme de chaîne et où la coopération est cruciale pour atteindre un objectif spécifique. Ce contexte a fait émerger la nécessité de faire inter-opérer une multitude de systèmes d’information, distribués, autonomes et hétérogènes. Sur la base d'une analyse approfondie des problèmes d'interopérabilité au sein du DMN, ces travaux ont abouti `à une approche générique conceptuelle d’interopérabilité multi-niveaux. Cette approche repose sur le standard ISA95 et l’approche d’ingénierie dirigée par les modèles (IDM), notre démarche vise à contribuer à l'amélioration de l'interopérabilité des systèmes d’entreprises au cours de la phase de fabrication du produit dans un DMN collaboratif. En s’intéressant aux trois niveaux d’interopérabilité, cette approche permet de s’assurer que les informations sont physiquement échangées (l'interopérabilité technique), sont comprises (l'interopérabilité sémantique) et sont bien utilisées pour atteindre le but pour lequel elles ont été produites (l'interopérabilité organisationnelle). La qualité et l'efficacité de l'approche proposée ont été confirmées par une application sur un cas concret de collaboration entre ERP et MES dans une usine de fabrication de stylos DEKENZ<br>Our thesis work deals with the study of interoperability in a collaborative and dynamic enterprise environment. Interoperability is considered as a key factor for collaboration that must be considered throughout the life cycle of the product. This is particularly important for collaborative enterprise networks, such as DMN, where a group of partners is connected in a chain model and where cooperation is crucial to achieve a specific goal.This context has led to the need for inter-operate a multitude of distributed, autonomous and heterogeneous information systems.Basis on a thorough analysis of the interoperability problems within the DMN, this work proposed a generic conceptual multi-level approach of interoperability. This approach relies on the use of ISA95 standard and Model Driven Engineering (MDE) method. It aims to contribute to the improvement of the interoperability of information systems during the manufacturing phase of the product in a collaborative DMN. By focusing on the three levels of interoperability, this approach ensures that information is physically exchanged (technical interoperability), is understood (semantic interoperability), and is well used to achieve the purpose for which it have been produced (organizational interoperability). The quality and effectiveness of the proposed approach were confirmed by an application on a concrete case of collaboration between ERP and MES in a DEKENZ pen manufacturing plant
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Marzougui, Borhen. "Contribution à la modélisation et à la vérification des systèmes multi agents." Thesis, Paris, CNAM, 2014. http://www.theses.fr/2014CNAM0918/document.
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Les Réseaux de Petri (RdP) sont actuellement les approches les plus prometteuses pour modéliser et vérifier les systèmes complexes tels que les Systèmes Multi Agents (SMA). De nombreuses solutions ont été proposées pour remédier aux problèmes de communication, de coordination et d’interaction entre les Agents. Cependant, il n’existe aucune en mesure de traiter, à la fois les aspects structurels et comportementaux, du moins à notre connaissance. La thèse s'intéresse à la problématique de modélisation formelle et de vérification automatique et semi-automatique de propriétés pour les Systèmes Multi Agents. Plus précisément, l'objectif consiste à proposer un nouveau modèle formel original basé sur les réseaux de Petri, les Réseaux de Petri à Agents (RdPA), qui permettent d’exprimer de manière consistante et plus précise les systèmes Multi Agents. Il s’intéresse de plus à l’extension de ce modèle aux fins de modéliser la migration des agents dans le cadre des systèmes à agents mobiles. Cette classe de modèle permet de s’intéresser à la vérification formelle de propriétés classiques comme notamment la vivacité ou l’absence d’interblocage dans le cadre des Systèmes Multi-Agent<br>Petri nets (PN) are currently the most promising approaches to model and to verify complex systems such as Multi Agent Systems (MAS). Several solutions have been proposed to solve the problems of communication, coordination and interaction among Agents. However, to best of our knowledge, none of this solution has able to handle both aspects: structural and behavioral. The thesis focuses on the problem of formal modeling and automatic and semi-automatic verification of properties in Multi Agent Systems. More specifically, the objective is to propose a new original formal model based on Petri nets, Agents Petri nets (APN), which express consistently more accurate a Multi Agent Systems. There is growing interest in the extension of this model for modeling the migration of Agents within the mobile Agent systems. This class of model allows focusing on the formal verification of classical properties such as alertness or absence of deadlock in the context of Multi Agent Systems
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Qamar, Ahsan. "An Integrated Approach towards Model-Based Mechatronic Design." Licentiate thesis, KTH, Mekatronik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-35374.
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Mechatronic design is an enigma. On the one hand, mechatronic products promise enhanced functionality, and better performance at reduced cost. On the other hand, optimizing mechatronic design concepts is a major challenge to overcome during the design process. In the past, less attention has been paid to the life phases of a mechatronic product, and it was assumed that modifications in electronics and software will ensure that the product performs to expectation throughout its life time. However it has been realized that introducing design changes in mechatronics is not easy, since it is difficult to assess the consequences of a design decision, both during the design process of a new product, and during a design modification. It is also realized that there is a strong need to consider the product's life phases during the early phases of product development. Furthermore, it is rather difficult to perform a design optimization since it requires introducing changes across different domains, which is not well supported by the methods and tools available today. This thesis investigates the topic of mechatronic design and attacks some of the major challenges that have been identified regarding the design of mechatronic products. The goal is to provide support to the designers to facilitate better understanding of the consequences of their design choices as early as possible. The work also aims to provide support for assessing alternative design concepts, and for optimizing a design concept based on requirements, constraints and designer preferences at the time of design. The thesis highlights three main challenges related to mechatronic product development: the need for a common language during conceptual design; the inadequate information transfer between engineering domains; and the difficulty in assessing the properties of competing mechatronic concepts. A model-based integration approach is presented, and these key challenges are considered in relation to an integrated modeling and design infrastructure. The approach is illustrated through the design of two mechatronic systems- a two degrees-of-freedom robot, and a hospital bed propulsion system. Initial results provide evidence of good potential for information transfer across mechatronic domains. Although SysML was used for the case studies, some important questions were raised about its suitability as a common language for mechatronics. Suggestions for future work are: to utilize the developed infrastructure and incorporate a capability to model and assess consequences of competing design concepts; provide support for optimizing these concepts; and evaluate the usefulness of the developed infrastructure in a real-world design setting. These efforts should provide ample information to the designer for making adequate decisions during the design process.<br>QC 20110629
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Paul, Parneet. "Using traditional modelling approaches for a MBR system to investigate alternate approaches based on system identification procedures for improved design and control of a wastewater treatment process." Thesis, De Montfort University, 2011. http://hdl.handle.net/2086/5387.
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The specific research work described in this thesis forms part of a much larger research project that was funded by the Technology Programme of the UK Government. This larger project considered improving the design and efficiency of membrane bioreactor (MBR) plant by using modelling, simulation and laboratory methods. This research work uses phenomenological mechanistic models based on MBR filtration and biochemical processes to measure the effectiveness of alternative behavioural models based upon input-output system identification methods. Both model types are calibrated and validated using similar plant layouts and data sets derived for this purpose. Results prove that although both approaches have their advantages, they also have specific disadvantages as well. In conclusion, the MBR plant designer and/or operator who wishes to use good quality, calibrated models to gain a better understanding of their process, should carefully consider which model type is selected based upon on what their initial modelling objectives are (e.g. using either a physically mechanistic model or an input-output behaviourial model). Each situation usually proves unique. In this regard, this research work creates a "Model Conceptualisation Procedure" for a typical MBR which can be used by future researchers as a theoretical framework which underpins any newly created model type. There has been insufficient work completed to date on using a times series input-output approach in the model development of a wastewater treatment plant, so only general conclusions can be made from this research work. However, it can be stated that this novel approach seems to be applicable for a membrane filtration model if care it taken to select appropriate input-output model structures, such as those suggested in the "Model Conceptualisation Procedure". In the case of the development of a MBR biological model, it is thought that a conventional Activated Sludge model produced by the IWA could be coupled to a input-output model structure as suggested by this report to give a hybrid model structure that may have the advantages of both model types. Further research work is needed in this area. Future work that should follow on from this research study should focus on whether these input-output models could be used for predictive control purposes, whether an integrated model could be created, and whether a benchmark could be created for the three main MBR configurations.
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Hallén, Malin, and Malin Rindeskär. "Let's turn the ABC around : The communication needs of young women in Kampala to prevent HIV/AIDS." Thesis, Jönköping University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-791.
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<p>This thesis is a part of a Bachelor’s degree within the field of Media and Communication at the School of Education and Communication at Jönköping University in Sweden. It is based on a Minor Field Study accomplished from the 30th of October to the 17th of December 2006 in Kampala, Uganda, East Africa.</p><p>The background of the research is that women who are between 15 and 24 years old and live in sub-Saharan Africa are more than tree times as likely to be infected by HIV/AIDS as men in the same age and location.</p><p>The purpose of the study is to discover indicators of what kind of health communication young women need to protect themselves from HIV/AIDS. The young women in the study are between 15 and 24 years old and live in areas affected by urban poverty in Kampala, Uganda.</p><p>To be able to gain a deeper understanding for the young women’s situation, the empirical study has been based on eleven conversation interviews made one by one with eleven young women. The procedure of the study has been guided by developed grounded theory and during the analysis of the interviews phenomenology has been used.</p><p>The result of the study shows that the ABC (Abstinence, Be faithful and Condom use) approach, which is used to fight HIV/AIDS in Uganda, is well known and carries an important message about prevention methods. At the same time it preaches moral in its hierarchical order which seems to judge women harder than men. The ABC approach was turned around by one of the young women in the study, which might create a more realistic message. It is however necessary to complement the approach with communication to young women about for example women’s rights and general sexual knowledge. This can be done through the use of verbal interpersonal communication, combined with easy access to HIV testing. The young women themselves can be effective peer educators and there is a need to let the interpersonal agenda be reflected in the political agenda, as well as in the developing media. To make young women able to act on their knowledge for protection, men and the community also need to be approached with gender sensitive messages.</p>
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Terrill, John R. "A critique of ethics training in the secular graduate business academy and a pedagogical approach for character formation in the lives of Christian MBA students." Online full text .pdf document, available to Fuller patrons only, 2003. http://www.tren.com.
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Herzig, Sebastian J. I. "A Bayesian learning approach to inconsistency identification in model-based systems engineering." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53576.
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Designing and developing complex engineering systems is a collaborative effort. In Model-Based Systems Engineering (MBSE), this collaboration is supported through the use of formal, computer-interpretable models, allowing stakeholders to address concerns using well-defined modeling languages. However, because concerns cannot be separated completely, implicit relationships and dependencies among the various models describing a system are unavoidable. Given that models are typically co-evolved and only weakly integrated, inconsistencies in the agglomeration of the information and knowledge encoded in the various models are frequently observed. The challenge is to identify such inconsistencies in an automated fashion. In this research, a probabilistic (Bayesian) approach to abductive reasoning about the existence of specific types of inconsistencies and, in the process, semantic overlaps (relationships and dependencies) in sets of heterogeneous models is presented. A prior belief about the manifestation of a particular type of inconsistency is updated with evidence, which is collected by extracting specific features from the models by means of pattern matching. Inference results are then utilized to improve future predictions by means of automated learning. The effectiveness and efficiency of the approach is evaluated through a theoretical complexity analysis of the underlying algorithms, and through application to a case study. Insights gained from the experiments conducted, as well as the results from a comparison to the state-of-the-art have demonstrated that the proposed method is a significant improvement over the status quo of inconsistency identification in MBSE.
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Tran, Ngoc Hoang. "Extension des systèmes MES au diagnostic des performances des systèmes de production au travers d'une approche probabiliste Bayésienne." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI048/document.
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Cette thèse s'inscrit dans le domaine de la diagnostic, en particulier de Manufacturing Execution System (MES) . Elle apporte sa contribution au diagnostic de système en présence de défaillances potentielles suit à une variation du TRS, un indicateur de performance qui donne une image de l’état de fonctionnement d’un système de production (équipement, ligne, atelier, usine) à travers l’estimation des pertes selon trois origines : disponibilité, performance, qualité. L’objectif est de fournir le maximum d’informations sur les origines d’une variation du TRS afin de permettre à l'exploitant de prendre la bonne décision. Aussi, sur la base d'un tel modèle, nous proposons une méthodologie de déploiement pour intégrer une fonction de diagnostic aux solutions MES existantes dans un contexte industriel<br>This Phd thesis takes place in the diagnostic field, especially in contexte of Manufacturing Execution System (MES). It contributes to the diagnostic system in the presence of potential failures following a triggering signal OEE drift, an indicator performance that gives a picture of the production system state (equipment, production line, site, and enterprise) by estimating downtime from 3 major origins: availability, performance, and quality. Our objective is to provide maximum information of the origins of an OEE variation and to support making the best decision for four categories users of OEE (operator, leader team, supervisor, direction). Also, basis on that model, the purpose will provides a deployment methodology to integrate with MES solution in an industrial context
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Leserf, Patrick. "Optimisation de l’architecture de systèmes embarqués par une approche basée modèle." Thesis, Toulouse, ISAE, 2017. http://www.theses.fr/2017ESAE0008/document.
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L’analyse de compromis d’un modèle système a pour but de minimiser ou de maximiser différents objectifs tels que le coût ou les performances. Les méthodes actuelles de type OOSEM avec SysML ou ARCADIA sont basées sur la classification ; il s’agit de définir les différentes variantes de l’architecture d’un système de base puis d’analyser ces variantes. Dans ces approches, les choix d’architecture sont contraints : la plateforme d’exécution et la topologie sont déjà figées. Nous proposons la notion de « points de décision » pour modéliser les différents choix du système, en utilisant de nouveaux stéréotypes. L’avantage est d’avoir une modélisation plus « compacte » des différentes variantes et de piloter l’exploration des variantes en utilisant des contraintes. Lorsque le concepteur définit l’architecture du système, des points de décisions sont insérés dans le modèle du système. Ils permettent de modéliser la redondance ou le choix d’une instance pour un composant, les variations des attributs d’un composant, ou l’allocation des activités sur les blocs. Les fonctions objectifs sont définies dans un contexte d’optimisation à l’aide du diagramme paramétrique de SysML. Nous proposons des transformations du modèle SysML vers un problème de satisfaction de contraintes pour l’optimisation (CSMOP) dont la résolution nous permet d’obtenir l’ensemble des architectures optimales. Cette transformation est implantée dans un démonstrateur (plug-in Eclipse) permettant une utilisation conjointe de l’outil Papyrus et de solveurs, disponibles sous forme de logiciels libres. La méthode est illustrée avec des cas d’étude constitués d’une caméra stéréoscopique puis d’un drone, l’ensemble étant modélisé avec Papyrus<br>Finding the set of optimal architectures is an important challenge for the designer who uses the Model-Based System Engineering (MBSE). Design objectives such as cost, performance are often conflicting. Current methods (OOSEM with SysML or ARCADIA) are focused on the design and the analysis of a particular alternative of the system. In these methods, the topology and the execution platform are frozen before the optimization. To improve the optimization from MBSE, we propose a methodology combining SysML with the concept of “decision point”. An initial SysML model is complemented with “decisions points” to show up the different alternatives for component redundancy, instance selection and allocation. The constraints and objective functions are also added to the initial SysML model, with an optimiza-tion context and parametric diagram. Then a representation of a constraint satisfaction problem for optimization (CSMOP) is generated with an algorithm and solved with an existing solver. A demonstrator implements this transformation in an Eclipse plug-in, combining the Papyrus open-source tool and CSP solvers. Two case studies illustrate the methodology: a stereoscopic camera sensor module and a mission controller for an Unmanned Aerial Vehi-cle (UAV)
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Le, Grand Yveline. "Approche méthodologique et technologique d'un site d'habitat du Pléistocène moyen : la grotte no 1 du Mas des Caves (Lunel-Viel, Hérault)." Aix-Marseille 1, 1993. http://www.theses.fr/1994AIX10013.
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La demarche qui a guide cette these tend vers une comprehension des comportements de l'homme dans son environnement et est exposee en introduction. Ce travail s'appuie surles artefacts lithiques et sur les structures d'habitat. La premiere partie expose l'historique des fouilles et le bilan des recherches anterieures effectuees sur le site. La seconde partie s'interesse, par le biais de l'analyse de la distribution spatiale des remontages, aux processus de formation des depots archeologiques et constitue un important point de discussion. La troisieme partie correspond a l'analyse technologique de l'assemblage lithique global et a pour but de degager les grandes tendances des comportements humains vis a vis de l'exploitation des ressources minerales : un approvisionnement local, une exploitation differentielle des materiaux par trois systemes de production adaptes a la qualite de la matiere premiere. La quatrieme partie constitue une approche de l'espace habite, par le biais des structures evidentes, en axant la demarche sur la reconnaissance de leur facture anthropique. En conclusion, par comparaison entre les resultats obtenus a lunel-viel 1 et les donnees des publications, quelques reflexions sur des comportements humains au pleistocene moyen sont avancees a titre d'hypotheses.
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Lebamba, Judicael. "Relation pollen-végétation-climat actuels en Afrique centrale : une approche numérique appliquée à la séquence quaternaire du lac Barombi Mbo, Cameroun." Montpellier 2, 2009. http://www.theses.fr/2009MON20203.
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Ce travail présente l'analyse de 80 nouveaux échantillons polliniques actuels d'Afrique centrale atlantique, en particulier de milieu forestier. Les assemblages polliniques obtenus ont été complétés par des données déjà existantes dans cette région, soit un total de 199 assemblages. L'application d'analyses statistiques et de la méthode de biomisation a permis de tester la fiabilité du contenu pollinique de cette base de données par rapport aux données botaniques mettant en évidence que plus de 95% des sites étaient correctement reconstruits en termes de biomes (forêt tropicale humide, forêt tropicale saisonnière, savane) ou de stades de succession forestière (savane, forêt secondaire, forêt mature). Sur une base de données polliniques plus étendue à l'Afrique de l'ouest, la méthode de biomisation a été appliquée à la séquence pollinique du lac Barombi Mbo, Cameroun, afin de recontruire les différents biomes et stades forestiers qui se sont succédés au cours des derniers 33 000 ans cal BP. L'application de la technique des meilleurs analogues, parallèlement à celle des réseaux de neurones artificiels a permis de reconstruire sur cette séquence la pluviosité et l'évapotranspiration moyennes annuelles, ainsi qu'un indice bioclimatique représentatif de la physionomie de la végétation<br>This work presents the analysis of 80 new modern pollen samples from central Africa, mainly in forest environment. Complemented by pollen assemblages previously obtained in this region, i. E. A total of 199 assemblages, statistical analysis and the application of the biomisation method have allowed to test the reliability of the pollen content of this dataset compared to local botanical data, showing that potential biomes (tropical rain forest, tropical seasonal forest, savanna) and forest successional stages (savanna, secondary forest, mature forest) were reconstructed with more than 95% of confidence level. Based on a more extended pollen database toward drier vegetations from West Africa and using the biomisation method, the best analogues and the artificial neural networks techniques, we proposed new quantitative and more precise reconstructions of the vegetation and climate at Lake Barombi Mbo, in Cameroon, during the last 33,000 cal yrs BP
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Gunnesby, Marica, and Karin Wallin. "Att mäta eller inte mäta : en studie om förhållandet mellan prestationsmätning och kulturell styrning i mer eller mindre osäkra omgivningar." Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-14786.
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Det finns i management control-litteraturen en efterfrågan på studier som tar ett helhetsperspektiv på styrsystem (Management Control Systems, MCS) och som förklarar hur dessa system bidrar till effektivitet hos organisationer. Utifrån ett contingency-synsätt undersöker vi i denna studie hur kulturell styrning och prestationsmätning som delar av MCS, tillsammans med den kontextuella variabeln osäkerhet i omgivningen, påverkar hur effektiva organisationer är. Vi antar en systemansats och önskar studera relationen mellan fler variabler, och därför tillämpas en klusteranalys där datamaterialet delas in i grupper med liknande karaktäristika. Då det är tveksamt om det finns en skillnad i effektivitet mellan de kluster vi identifierar, och för att få en bättre förståelse för vårt resultat, väljer vi att analysera detta utifrån två olika perspektiv. Utifrån det ena perspektivet antas organisationernas effektivitet skilja sig från varandra. Sett från detta perspektiv verkar en hög grad av prestationsmätning tillsammans med en hög grad av kulturell styrning vara effektivt under hög grad av osäkerhet i omgivningen. Utgångspunkten i det andra perspektivet är däremot att alla de företag som existerar och kan studeras är effektiva, och utifrån denna analys verkar det tvärtemot den tidigare analysens resultat som att en lägre grad av prestationsmätning tillsammans med en lika stor grad av kulturell styrning är mer effektivt i osäkra omgivningar, även om detta samband är något oklart. Under låg grad av osäkerhet i omgivningen visar analyser ur båda perspektiven att en hög grad av kulturell styrning tillsammans med en låg grad av prestationsmätning är en effektiv kombination. Dessutom visar det sig utifrån det sistnämnda perspektivet att även hög grad av båda styrmekanismerna är effektivt i mindre osäkra omgivningar.<br>Within the management control literature, studies have been requested that take a holistic view of Management Control Systems (MCS) and that explain how these systems contribute to organizational effectiveness. In this study, from a contingency perspective, we examine how cultural control and performance measurement as parts of the MCS, together with the contextual variable environmental uncertainty, affect the effectiveness of organizations. Adopting a systems approach we wish to study the relationship between several variables and therefore use a cluster analysis to divide the data into groups with similar characteristics. Since it is not clear whether there are any differences in effectiveness between the identified clusters and to get a better understanding of our findings, we choose to analyze the results from two different perspectives. Adopting one of the perspectives, the organizations are assumed to be unequally effective. From this perspective a high degree of performance measurement combined with a high degree of cultural control seem to be effective under high degrees of environmental uncertainty. From the other perspective it is implicitly understood that all of the observed organizations are effective since they exist. Seen from this, second, perspective it seems that a lower degree of performance measurement together with an equal degree of cultural control is more effective in uncertain environments, even though this relationship is somewhat vague. Under a low degree of environmental uncertainty, analyses from both perspectives show that a high degree of performance measurement together with a low degree of cultural control in an effective combination. Furthermore, the analysis from the second perspective indicates that also a high degree of both of the control variables is effective in high degrees of environmental uncertainty.
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Kitio, Teussop Rosine. "Gestion de l’ouverture au sein d’organisations multi-agents : une approche basée sur des artefacts organisationnels." Thesis, Saint-Etienne, EMSE, 2011. http://www.theses.fr/2011EMSE0630/document.
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Les systèmes multi-agents sont des systèmes dans lesquels des entités logiciellesappelées agents interagissent de façon autonome dans des environnements partagés. Ces dernièresannées, de nombreuses recherches sur les organisations multi-agents ont été menées etdivers modèles organisationnels ont été proposés. Cependant, ils n’offrent pas de solution pourune gestion effective de la problématique d’ouverture dans des organisations multi-agents normatives.Dans cette thèse, nous nous sommes intéressées à l’étude de cette problématique etdonc à la spécification des besoins relatifs à la mise en oeuvre de l’ouverture au sein d’organisationmulti-agent. Nous avons ainsi identifié trois propriétés caractéristiques de cette problématique: l’interopérabilité d’une organisation avec son environnement extérieur et interne, lagestion des entrées / sorties et la gestion du contrôle et de la régulation des agents. Pour répondreà ces propriétés, nous avons proposé un langage de modélisation d’organisation (OML)MOISE qui est une extension de Moise+. MOISE permet de spécifier de façon explicite lesprocessus d’entrée / sortie dans une organisation et notamment les exigences relatives auxmissions, buts, et rôles de l’organisation. Nous avons également proposé une infrastructure degestion d’organisation (OMI) ORA4MAS qui s’inspire du méta-modèle Agents et Artifacts(A&A). Nous avons défini le concept d’artefact organisationnel pour implémenter les fonctionnalitéscorrespondant aux spécifications du langage MOISE. Nos propositions ont été illustréesavec une spécification d’organisation de gestion de la construction d’un édifice. La miseen oeuvre des propriétés d’ouverture a été expérimentée avec la gestion des processus d’entrée/ sortie des agents, la négociation des clauses de contrat, la coordination des coopérations desagents à la réalisation des buts de construction d’un édifice, le contrôle des comportements desagents relativement aux normes de l’organisation ainsi que leur régulation<br>Multi-Agent Technology concerns the development of decentralized and open systemscomposed of different agents interacting in a shared environment. In recent years, organizationhas become an important in this research field. Many models have been, and are still,proposed. While no concensual model emerges of these different works, it appears that theyall lack the ability to build open and normative organizations in the sense of management ofentry / exit of agents into organization but also decentralized control / regulation of the autonomyof the agents. In this thesis, our objective consists in the definition of a new modeladdressing these requirements. Ours reseaches allow us to extend theMOISE+ organizationalmodeling language (OML) in a new version namming MOISE. In this one we define an Entry/ Exit specification allowing to explicitly specify the ways in which the agents can enter orexit in or from an organisation by providing some requirements according to the missions, thegoals and the roles of the organisation. The organizational management infrastructure (OMI)ORA4MAS proposed take advantage of the Agents and Artifacts (A&A) approach. We definedthe Organizational Artifacts concept as the basic building block of our OMI for themanagement of organized and open MAS. To focus our study, the organizational artifacts willbe defined considering the OML specification of the MOISE model. We experimented ourproposal with the specification of an application aiming to manage the build of a house. Wethen experimented the management of the candidate agents to enter in the organisation and cooperatewith the other to build the house according to a specified social scheme, the specifiednorms and their contract clauses negociated when they will be admitted in the organisation
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Mazyad, Hanaa. "Une approche Multi-agents à Architecture P2P pour l'apprentissage collaboratif." Phd thesis, Université du Littoral Côte d'Opale, 2013. http://tel.archives-ouvertes.fr/tel-00845225.
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Les Systèmes multi-agents ou SMA proposent une approche originale de conception de systèmes intelligents et coopératifs. Ils se caractérisent par la distribution du contrôle global du système et par la présence d'agents autonomes évoluant dans un environnement partagé et dynamique. De plus, il existe plusieurs interdépendances entre les buts des agents, leurs capacités et les ressources qu'ils utilisent, donc afin d'éviter d'éventuels conflits, de favoriser la synergie des activités des agents et de partager les ressources de l'environnement commun, il est important que les agents coordonnent leurs actions. Nous nous sommes intéressés, dans le cadre de cette thèse, au déploiement des systèmes multi-agents sur une architecture pair à pair (Peer-to-Peer ou P2P) et ceci dans le but d'établir la communication entre ces agents et les relier entre eux. Cependant, du fait de la nature dynamique des systèmes P2P où chaque pair peut apparaître et disparaître à tout moment, des nouveaux problèmes se posent pour la coordination d'agents nécessitant des mécanismes de coordination adaptés au contexte spécifique des P2P. Pour cela, nous avons proposé une méthode de formation de groupe comme solution à ces problèmes. Nous nous sommes intéressés ensuite à l'application des systèmes multi-agents à architecture P2P au domaine d'apprentissage collaboratif en ligne où des apprenants contribuent aux apprentissages du groupe, et en retour, le groupe contribue à ceux des apprenants et c'est la cohérence du collectif qui permet d'atteindre l'objectif. Cependant, l'apprentissage collaboratif à distance implique des nouveaux rôles pour l'enseignant ainsi que pour les apprenants. Il est donc essentiel de définir ces rôles pour identifier les besoins qui en découlent pour pouvoir intégrer à l'outil informatique des fonctionnalités afin de satisfaire ces besoins. En effet, il est essentiel de fournir aux enseignants et apprenants la possibilité d'avoir des informations sur la progression de leur apprentissage ainsi que sur les niveaux de collaboration et de sociabilité de chaque apprenant et du groupe. Enfin, nous avons proposé, comme application de nos travaux, un système appelé COLYPAN (COllaborative Learning sYstem for Project mANagment) conçu pour l'apprentissage à distance et de façon collaborative de la gestion des projets.
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Petit, Sophie. "Étude des méthodes de prédiction de taux d'erreurs en orbite dans les mémoires : nouvelle approche empirique." Toulouse, ENSAE, 2006. http://www.theses.fr/2006ESAE0015.
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Le phénomène de Single Event Upset (SEU) correspond au basculement logique d'un point mémoire suite au passage d'une particule énergétique. Les composants de type SRAM et DRAM, soumis à l'environnement spatial, sont sensibles aux SEU, il est alors primordial de prévoir leur sensibilité avant de les intégrer dans les missions spatiales. L'enjeu actuel est de concevoir un modèle de prédiction fiable utilisable pour tout type de mémoire, même fortement intégrée. La première phase de ce travail est une analyse des retours d'expériences embarquées qui a permis d'évaluer les modèles de prédiction standard, basés sur la modélisation IRPP, en comparant directement les taux d'erreurs en vol aux taux prédits, et démontrant leur incapacité à fournir des prédictions correctes. L'analyse des sources d'erreurs possibles a montré la difficulté d'améliorer les modèles standard, nous amenant alors à proposer une tout autre technique de prédiction. Ainsi, la méthode de prédiction empirique, basée sur la sensibilité mesurée des composants aux SEU, pour plusieurs angles d'incidence des particules, est présentée et mise en œuvre sur un ensemble de composants ; elle donne des résultats très encourageants. Une étude des événements multiples a été menée : elle montre que la diffusion des porteurs est à prendre en compte dans la modélisation des mécanismes de collection de charge mis en jeu. Enfin, des simulations numériques 3D couplées à des modèles analytiques simples permettent l'étude quantitative des mécanismes de collection dans une des structures ayant volé : ces outils ont confirmé le rôle majeur de la diffusion dans les SEU.
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Savy, Benoît. "Hydro-limnologie du haut bassin de la Charente : une approche géographique appliquée aux relations lac de barrage - émissaire : la température de l'eau en aval des lacs de Lavaud et Mas Chaban." Limoges, 2006. http://www.theses.fr/2006LIMO2012.
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Le Bassin de la Charente connaît depuis plusieurs décennies une pression grandissante de certaines activités sur la ressource en eau. Pour tenter de satisfaire ces exigences, deux retenues ont été mises en eau dans le haut bassin de la Charente, les lacs Lavaud et de Mas Chaban, dont la capacité de stockage avoisine les 25 millions de mètres cubes, soutiennent l'étiage de la Charente depuis 1990 pour le premier, et 2000, pour le second. Le plus récent des deux est équipé d'un destratificateur à injection d'air brisant la stratification thermique estivale. De fait, le lac de Mas Chaban a une structuration thermique forcée alors que celle de Lavaud évolue plus librement, en fonction des modalités du soutien d'étiage. Ce travail a pour but de comprendre la thermique lacustre, contrainte dans la retenue de Mas Chaban et libre dans celle de Lavaud, pour analyser ses répercussions en aval, lors des lâchers. Les résultats montrent que durant certaines périodes les modifications thermiques sont résorbées au bout de quelques kilomètres, alors que pour d'autres, elles sont encore décelables à plusieurs dizaines de kilomètres en aval de deux déversoirs.
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Lequay, Victor. "Une approche ascendante pour la gestion énergétique d'une Smart-Grid : modèle adaptatif et réactif fondé sur une architecture décentralisée pour un système générique centré sur l'utilisateur permettant un déploiement à grande échelle." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1304.
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Le domaine de la gestion de l'énergie dans les smart grids a été largement exploré ces dernières années, de nombreuses approches différentes étant proposées dans la littérature. En collaboration avec notre partenaire industriel Ubiant, qui déploie des solutions d'optimisation énergétique du bâtiment, nous avons mis en évidence le besoin d'un système vraiment robuste et évolutif exploitant la flexibilité de la consommation résidentielle pour optimiser l'utilisation de l'énergie au sein d'une smart grid. Dans le même temps, nous avons observé que la majorité des travaux existants se concentraient sur la gestion de la production et du stockage et qu'aucune des architectures proposées n'étaient véritablement décentralisées. Notre objectif était alors de concevoir un mécanisme dynamique et adaptatif permettant de tirer parti de toute la flexibilité existante tout en garantissant le confort de l'utilisateur et une répartition équitable des efforts d'équilibrage ; mais aussi de proposer une plate-forme ouverte et modulaire avec laquelle une grande variété d'appareils, de contraintes et même d'algorithmes pourraient être interfacés. Dans cette thèse, nous avons réalisé (1) une évaluation des techniques actuelles de prévision de la consommation individuelle en temps réel, dont les résultats nous ont amenés à suivre (2) une approche ascendante et décentralisée pour l'ajustement diffus résidentiel reposant sur un mécanisme de compensation pour assurer un effacement stable. Sur cette base, nous avons ensuite construit (3) une plate-forme générique centrée sur l'utilisateur pour la gestion de l'énergie dans les réseaux intelligents, permettant une intégration aisée de plusieurs périphériques, une adaptation rapide à l'évolution de l'environnement et des contraintes, ainsi qu'un déploiement efficace<br>The field of Energy Management Systems for Smart Grids has been extensively explored in recent years, with many different approaches being described in the literature. In collaboration with our industrial partner Ubiant, which deploys smart homes solutions, we identified a need for a highly robust and scalable system that would exploit the flexibility of residential consumption to optimize energy use in the smart grid. At the same time we observed that the majority of existing works focused on the management of production and storage only, and that none of the proposed architectures are fully decentralized. Our objective was then to design a dynamic and adaptive mechanism to leverage every existing flexibility while ensuring the user's comfort and a fair distribution of the load balancing effort ; but also to offer a modular and open platform with which a large variety of devices, constraints and even algorithms could be interfaced. In this thesis we realised (1) an evaluation of state of the art techniques in real-time individual load forecasting, whose results led us to follow (2) a bottom-up and decentralized approach to distributed residential load shedding system relying on a dynamic compensation mechanism to provide a stable curtailment. On this basis, we then built (3) a generic user-centered platform for energy management in smart grids allowing the easy integration of multiple devices, the quick adaptation to changing environment and constraints, and an efficient deployment
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Shen, Ying. "Élaboration d'ontologies médicales pour une approche multi-agents d'aide à la décision clinique." Thesis, Paris 10, 2015. http://www.theses.fr/2015PA100040/document.
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La combinaison du traitement sémantique des connaissances (Semantic Processing of Knowledge) et de la modélisation des étapes de raisonnement (Modeling Steps of Reasoning), utilisés dans le domaine clinique, offrent des possibilités intéressantes, nécessaires aussi, pour l’élaboration des ontologies médicales, utiles à l'exercice de cette profession. Dans ce cadre, l'interrogation de banques de données médicales multiples, comme MEDLINE, PubMed… constitue un outil précieux mais insuffisant car elle ne permet pas d'acquérir des connaissances facilement utilisables lors d’une démarche clinique. En effet, l'abondance de citations inappropriées constitue du bruit et requiert un tri fastidieux, incompatible avec une pratique efficace de la médecine.Dans un processus itératif, l'objectif est de construire, de façon aussi automatisée possible, des bases de connaissances médicales réutilisables, fondées sur des ontologies et, dans cette thèse, nous développons une série d'outils d'acquisition de connaissances qui combinent des opérateurs d'analyse linguistique et de modélisation de la clinique, fondés sur une typologie des connaissances mises en œuvre, et sur une implémentation des différents modes de raisonnement employés. La connaissance ne se résume pas à des informations issues de bases de données ; elle s’organise grâce à des opérateurs cognitifs de raisonnement qui permettent de la rendre opérationnelle dans le contexte intéressant le praticien.Un système multi-agents d’aide à la décision clinique (SMAAD) permettra la coopération et l'intégration des différents modules entrant dans l'élaboration d'une ontologie médicale et les sources de données sont les banques médicales, comme MEDLINE, et des citations extraites par PubMed ; les concepts et le vocabulaire proviennent de l'Unified Medical Language System (UMLS).Concernant le champ des bases de connaissances produites, la recherche concerne l'ensemble de la démarche clinique : le diagnostic, le pronostic, le traitement, le suivi thérapeutique de différentes pathologies, dans un domaine médical donné.Différentes approches et travaux sont recensés, dans l’état de question, et divers paradigmes sont explorés : 1) l'Evidence Base Medicine (une médecine fondée sur des indices). Un indice peut se définir comme un signe lié à son mode de mise en œuvre ; 2) Le raisonnement à partir de cas (RàPC) se fonde sur l'analogie de situations cliniques déjà rencontrées ; 3) Différentes approches sémantiques permettent d'implémenter les ontologies.Sur l’ensemble, nous avons travaillé les aspects logiques liés aux opérateurs cognitifs de raisonnement utilisés et nous avons organisé la coopération et l'intégration des connaissances exploitées durant les différentes étapes du processus clinique (diagnostic, pronostic, traitement, suivi thérapeutique). Cette intégration s’appuie sur un SMAAD : système multi-agent d'aide à la décision<br>The combination of semantic processing of knowledge and modelling steps of reasoning employed in the clinical field offers exciting and necessary opportunities to develop ontologies relevant to the practice of medicine. In this context, multiple medical databases such as MEDLINE, PubMed are valuable tools but not sufficient because they cannot acquire the usable knowledge easily in a clinical approach. Indeed, abundance of inappropriate quotations constitutes the noise and requires a tedious sort incompatible with the practice of medicine.In an iterative process, the objective is to build an approach as automated as possible, the reusable medical knowledge bases is founded on an ontology of the concerned fields. In this thesis, the author will develop a series of tools for knowledge acquisition combining the linguistic analysis operators and clinical modelling based on the implemented knowledge typology and an implementation of different forms of employed reasoning. Knowledge is not limited to the information from data, but also and especially on the cognitive operators of reasoning for making them operational in the context relevant to the practitioner.A multi-agent system enables the integration and cooperation of the various modules used in the development of a medical ontology.The data sources are from medical databases such as MEDLINE, the citations retrieved by PubMed, and the concepts and vocabulary from the Unified Medical Language System (UMLS).Regarding the scope of produced knowledge bases, the research concerns the entire clinical process: diagnosis, prognosis, treatment, and therapeutic monitoring of various diseases in a given medical field.It is essential to identify the different approaches and the works already done.Different paradigms will be explored: 1) Evidence Based Medicine. An index can be defined as a sign related to its mode of implementation; 2) Case-based reasoning, which based on the analogy of clinical situations already encountered; 3) The different semantic approaches which are used to implement ontologies.On the whole, we worked on logical aspects related to cognitive operators of used reasoning, and we organized the cooperation and integration of exploited knowledge during the various stages of the clinical process (diagnosis, prognosis, treatment, therapeutic monitoring). This integration is based on a SMAAD: multi-agent system for decision support
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Wu, Quentin. "Capitalisation et réutilisation de savoir-faire dans une approche d’ingénierie système basée sur les modèles : application au système de distribution électrique d’aéronefs." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0112.
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L’ « Ingénierie Système Basée sur les Modèles » (ISBM), est une approche d’Ingénierie Système dans laquelle la modélisation est le support de toutes les activités d’ingénierie. Elle est plébiscitée par les industriels comme étant une manière de satisfaire le besoin de prise en compte de la complexité croissante des systèmes, pour lesquels les pratiques d’Ingénierie Systèmes centrées sur les documents arrivent à leurs limites. Cependant, de nombreux retours d’expérience sur la transition vers l’ISBM soulignent la forte courbe d’apprentissage nécessaire à sa mise en œuvre, ainsi que la difficulté pour les ingénieurs de se l’approprier. Dans ce contexte, la contribution de ce manuscrit vise à faciliter l’adoption de l’ISBM par la valorisation des actifs d’ingénierie. Elle cherche à systématiser la capitalisation et la réutilisation de savoir-faire en utilisant le concept de « patron », dont le rôle et le périmètre sont définis dans le cadre de l’ISBM. De manière à accompagner la montée en maturité des processus de capitalisation et de réutilisation au sein d’une entreprise, elle introduit une échelle de maturité permettant d’évaluer une situation d’ingénierie de manière à cibler les efforts à fournir. La contribution porte également sur la formalisation de niveaux d’abstraction des patrons capitalisés et de mécanismes de transition entre ces niveaux d’abstraction. Sur cette base, elle formalise les processus de l’approche « Minage-Maturation-Implémentation de Patrons » (MMIP), dont l’objectif est d’être un guide pour les ingénieurs dans la capitalisation et la réutilisation d’actifs d’ingénierie. La contribution a été éprouvée sur un cas d’étude, dans le cadre d’un nouveau projet industriel au sein de Safran Electrical & Power. L’objectif était de démontrer l’existence de patrons techniques, de les formaliser et de les réutiliser dans un contexte d’ISBM<br>Model Based System Engineering (MBSE) is a System Engineering approach in which modeling is the backbone of all engineering activities. It is widely accepted by the industry as a way to satisfy the need to take into account the ever-increasing complexity of systems, for which document-based Systems Engineering practices are reaching their limits. However, numerous feedbacks on the transition to MBSE highlight the steep learning curve required for its implementation, as well as the difficulty for engineers to master it. In this context, the contribution of this manuscript aims at facilitating the adoption of MBSE through the valorization of engineering assets. It seeks to systematize the capitalization and reuse of know-how by using the concept of "pattern", whose role and scope are defined within the framework of MBSE. In order to increase the maturity of capitalization and reuse processes within a company, a maturity scale is also introduce to assess an engineering situation in order to target the efforts to be made. The contribution also deals with the formalization of levels of abstraction of capitalized patterns and of transition mechanisms between these levels of abstraction. On this basis, it formalizes the “Mining-Maturation-Implementation of Patterns” (MMIP) process, whose objective is to be a guide for engineers in the capitalization and reuse of engineering assets. The contribution has been tested on a case study, within the framework of a new industrial project at Safran Electrical & Power. The objective was to demonstrate the existence of patterns, to formalize them and to reuse them in an MBSE context
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Sadaoui, Mahrez. "Variabilité et évolution des apports de matières en suspension dans la zone côtière : approche multi-échelle dans le bassin de la Méditerranée." Thesis, Perpignan, 2016. http://www.theses.fr/2016PERP0037.
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Les fleuves assurent le transport des matières particulaires vers la mer, introduisant ainsi du sable, des nutriments et des contaminants. Les fleuves méditerranéens sont de part leurs caractéristiques (relief accidenté, climat contrasté) naturellement riches en matières en suspension (MES), mais leurs flux sont aujourd’hui largement modifiés par la construction de barrages. Cette étude vise à comprendre la variabilité et l’évolution des apports fluviaux en MES en Méditerranée par une approche multi-échelle : (1) Dans le Golfe du Lion, les flux de MES (et nutriments associés) ont été estimés à long terme grâce à la nouvelle méthode SiRCA (Simplified Rating Curve Approach). La lithologie est le contrôle principal pour la variabilité spatiale de ces flux, ce qui attribue au Rhône le rôle dominant dans les apports totaux (95%). (2) Dans le bassin méditerranéen, une quantification complète des apports par l’ensemble des fleuves a été établie (modélisation empirique) dont 35% de MES sont aujourd’hui retenus dans les grands barrages (GB). (3) Dans le bassin du Maghreb, la retenue sédimentaire par les petits barrages a pu être estimée égale à celle des GB<br>Rivers ensure the transport of suspended particulate matter (SPM) to the Sea, introducing sand, nutrients and contaminants. According to their drainange basin characteristics (mountainous relief, contrasting climates), Mediterranean rivers are naturally rich in SPM, but their fluxes are largely altered today because of damming. This study aims to understand the variability and evolution of the riverine SPM inputs to the Mediterranean sea by a multiscale approach. (1) In the Gulf of Lion, total SPM fluxes (and associated nutrients) were estimated on the long term through the development of a new method SiRCA (Simplified Rating Curve Approach). The lithology is the main control for the spatial variability of these fluxes, which attributes to the Rhône River the dominant role in the overall fluxes (95%). (2) In the Mediterranean basin, empirical modeling could be established which allows for the first time a complete quantification of the inputs by all the rivers in this region (997 Mt/an). It also confirms the importance of lithology among the dominant controlling factors. By combining this model with a database of large dams in this region, it has been calculated that about 35% of SPM are today retained behind dams. (3) In the Maghreb basin, finally the role of sediment retention by small dams and hillside reservoirs has been studied. A new database on these reservoirs was created and combined with the database on large dams. This study demonstrates that small dams probably retain the same amount of sediments that large dams
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Chang, Po-Jen, and 張博仁. "A Nonparametric Approach to Pricing and Hedging MBS Via Kernel-Density Regression Model." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/34145936749136671434.
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碩士<br>國立中正大學<br>財務金融研究所<br>90<br>The Financial Asset Securitization Law was just passed by Taiwan’s legislature in June, 2002. The law is expected to address stagnancy in Taiwan''s capital markets, it could potentially reinvigorate domestic banks by allowing their asset-backed loans to be packaged into securities. Hence, this new law facilitates the mechanism whereby banks can re-package collateral and sell it to investors as securities, helping to increase the "liquidity of banks" and also diversifying their risks. Financial assets such as mortgages, car loans or credit card receivable accounts can be repackaged into small values in the form of securities certificates or beneficiary certificates for sales to investors. Among all kinds of financial asset products, mortgage-backed security is the most popular in US market.
The current way of solving this valuation problems has been to assume a stochastic process for term structure movements and to employ either a simulation/forecasting pricing approach or an empirical/statistical approach for prepayment behavior and price process. In this article, we propose a nonparametric pricing method, kernel-density regression approach, to price weekly TBA (to be announced) GNMA securities. Here we have three goals: the first is to find out what is the best way to reduce the number of independent variables to use for the kernel model and other model and what is the remaining inputs, the second is to assess the pricing effect of kernel-density regression approach versus other pricing models. Finally, we want to recognize the hedging effectiveness of kernel-density regression approach and other models. For comparison, we use another two popular pricing approaches: ordinary least squares (OLS) and a parametric model (proprietary practitioner model).
According empirical results, we find that kernel-density regression model perform more effectively on estimating MBS price than the other two models mentioned in this article, except in out-of-sample of time-series sampling. Moreover, kernel-density regression model have better pricing effect on random sampling than on time-series sampling, especially in out-of-sample. In addition, SAS MAXR procedure and principal component analysis can effectively reduce the number of independent variables used for both kernel-density regression model and OLS model. In regard to the hedging effect, the results of in-of-sample are approximately the same with pricing effect analysis. But, in contrast with in-of-sample, Kernel(3-month rate) is the best way to hedge the MBS in out-of-sample, especially on random sampling.
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Kaliski, Rafael, and 柯拉飛. "A game theoretic approach to sponsored LTE MBMS & D2D services." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/w8k78h.
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博士<br>國立臺灣大學<br>電機工程學研究所<br>105<br>Abstract
Two of the goals of the 3rd Generation Partnership Project (3GPP) are to deploy Long Term Evolution (LTE) Multimedia Broadcast/Multicast Service (MBMS) and commercial Device to Device (D2D) Proximity Services (ProSe). As the mobile market is nearing saturation, and additional spectrum is scarce, Service Providers (SPs) are searching for additional sources of revenue. Currently, both MBMS and D2D services lack feasible economic models for wide-spread deployment. We present two economically feasible models for MBMS and commercial D2D services. Both of these models can be viewed as solving resource allocation problems, where the bandwidth is the resource being allocated by each of the aforementioned services and the advertisers are the sponsors of said service.
Wireless Networking Resource Allocation problems are often combinatorial optimization problems, which are considered NP-hard and are solvable via an exhaustive search. Furthermore, when the players interested in acquiring resources exhibit rationality, they may try to manipulate the resource allocation mechanism by acting selfishly and misreport their private information in order to increase their resource allocation / reduce their costs. As such, these resource allocation problems are considered complex due to the rationality of the players and the combinatorial optimization. Based on a game-theoretic analysis, we identify the selfish behaviors of the players and propose novel solutions to incentivize the players to truthfully reveal their private information in a tractable computational complexity. Simulations are presented for evaluating the performance of each of the proposed solutions.
We first study the most recent release of LTE MBMS, i.e. LTE Rel’14 FeMBMS. LTE FeMBMS opens the possibilities for a higher percentage of cell capacity to be allocated for MBMS services, in addition to inter-Mobile Network Operator dual connectivity, dynamic MBMS, and non-subscriber reception of MBMS services. Furthermore, shared content distribution is enabled via shared eMBMS networks (SEN) and the content provider can determine the method of content delivery, be it unicast or multicast.
For streaming real-time video, fast and efficient resource allocation is necessary. Real-time video is expected to make use of MBMS operation On-Demand (MooD). For MBMS resource allocation at the MAC-layer, integer linear programming (ILP) can be used to achieve an optimal resource allocation among multiple video streams. Yet ILP is known to be NP-hard. We observe that for resource allocation at the MAC-layer, where multiple MAC allocation periods are required for the complete transmission of a video frame, a gradient-based resource allocation approach can achieve similar performance to that of ILP. Unlike ILP, in terms of computational complexity, our proposed gradient-based approach runs in P-time.
For the MBMS services, we present a mobile TV system where the advertisers sponsor the TV service. We first study how the impact of viewership of a TV station and its associated bandwidth affects each advertiser’s valuation. By using mechanism design, we design a truthful voting mechanism to accurately capture each viewer’s current TV channel they are watching. The bandwidth allocated to each TV station is dependent on the current resource demands of the streaming videos and the viewership statistics. Based on the projected viewership and bandwidth allocated to each TV station, we design a truthful auction to allocate each advertisement slot to the set of advertisers interested in broadcasting their advertisements and consequently sponsoring said MBMS service.
Finally, for commercial D2D services, we observe that SPs most likely have underutilized spectrum they are looking to monetize. We investigate how commercial D2D services, which can be limited to sub-sectors, can make use of SP controlled underutilized spectrum. The under-utilized spectrum allocation problem is formulated as an SP-controlled gap allocation problem; gaps are used by commercial D2D services. As D2D has a limited range, the gaps can be allocated to multiple D2D stations (UEs transmitting D2D services) within a sector. Based on the channel conditions of each D2D station, the associated bandwidth is auctioned off to advertisers who are interested in broadcasting their advertisements to the associated localized area. To perform the bandwidth allocation in a reasonable time, we derive a truthful auction which has a computational complexity in P-time and has a similar profit performance to the theoretically optimal VCG auction.
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Silva, Ana Margarida Arantes. "Onfalocelo e gastrosquise: estudo de casos diagnosticados na MBB." Master's thesis, 2019. http://hdl.handle.net/10316/89815.
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Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina<br>Introdução: a gastrosquise e o onfalocelo são as malformações major congénitas daparede abdominal anterior mais frequentes e caracterizam-se por herniação das vísceras. Porserem patologias distintas, a melhor caracterização e compreensão destas e dasmalformações associadas é importante de forma a melhorar a abordagem e seguimentodestes doentes e consequentemente aumentar a sobrevida e a qualidade de vida.Objetivo: determinar a incidência de onfalocelos e gastrosquises na Maternidade BissayaBarreto (MBB), caracterizar os casos diagnosticados, bem como a avaliação da sua evoluçãocirúrgica no Hospital Pediátrico de Coimbra (HPC).Metodologia: foram estudados retrospetivamente todos os casos diagnosticados comogastrosquise ou onfalocelo na MBB e posteriormente seguidos no HPC, no período decorridoentre janeiro de 1991 e dezembro de 2017.Resultados: de um total de 78 defeitos diagnosticados, 52 correspondem a onfalocelose 26 a gastrosquises, sendo a prevalência de 6,53 e 3,26:10000 nascimentos, respetivamente.Dos nados vivos (41), 49% apresentavam onfalocelos e 51% gastrosquises, sendo aprevalência de 2,51 e 2,63:10000 nascimentos, respetivamente. A taxa de deteção estesdefeitos em período pré-natal foi de 94%. A percentagem de óbitos fetais foi 61% dosonfalocelos e 19% das gastrosquises. Na totalidade dos casos, as malformações associadasestiveram presentes em 80% dos casos de onfalocelos e 35% de gastrosquises. Aprematuridade registou-se em 37% dos onfalocelos e 71% dos gastrosquises. A abordagemcirúrgica mais utilizada foi redução com encerramento primário (63% dos onfalocelos e 95%das gastrosquises). Dos onfalocelos 3/17 e das gastrosquises 7/21 necessitaram dereintervenção cirúrgica. Registaram-se 21% de óbitos no grupo dos onfalocelos e, comosequelas, 14% de síndromes de intestino curto no grupo das gastrosquises.Conclusões: o diagnóstico pré-natal (DPN) é de suma importância de forma a aumentara sobrevida e a qualidade de vida dos doentes com estes defeitos. Devido ao protocoloestabelecido entre a MBB e os cuidados de saúde primários da sua área de influência, a taxade deteção neonatal destes defeitos foi muito elevada. Por fim, a avaliação destas gravidezesnum centro de apoio perinatal diferenciado com ligação ao serviço de pediatria cirúrgicapermite uma orientação célere de forma a melhorar o prognóstico destes recém-nascidos.<br>Introduction: omphaloceles and gastroschisis are the most common congenitalabdominal wall defects represented by the extra peritoneal herniation of the abdominal viscera.Since they are different pathologies it is importante to have a full understanding of theircharacteristics and associated malformations, in order to chose the best treatment, andconsequently have the best prognosis and quality of life.Objective: to determine the incidence of omphaloceles and gastroschisis in the MBB,characterise the cases diagnosed and evaluate their cirurgical evolution in the HPC.Methodology: retrospective study of all cases diagnosed at the MBB as omphaloceles orgastroschisis which later were followed at the HPC in the period between January 1991 andDecember 2017.Results: In a total of 78 diagnosed defects, 52 corresponded to omphaloceles and 26 togastroschisis, being the prevalence of 6,53 and 3,26: 10 000 births, respectively. Regardinglive births (41), 49% had omphalocele and 51% gastroschisis, with a prevalence of 2,51 and2,63: 10 000 births, respectively. The rate of detection of these defects in the prenatal periodwas 94%. The percentage of fetal deaths was 61% of omphaloceles and 19% of gastroschisis.In our case serie, the associated malformations were present in 80% of cases of omphalocelesand 35% of gastroschisis. Prematurity was present in 37% of omphaloceles and 71% ofgastroschisis. The most used surgical approach was reduction with primary closure (63% ofomphaloceles and 95% of gastroschisis). Surgical reintervetion was required in 3/17omphaloceles and in 7/21 gastroschisis. There were 21% of deaths in the omphafolecelesgroup and, as sequels, 14% of short bowel syndromes in the gastroschisis group.Conclusions: prenatal diagnosis is extremely important in order to increase the survivaland quality of life of patients with these defects. Due to the protocol established between MBBand the primary care of its influence area, the rate of neonatal detection of these defects wasvery high. Finally, the evaluation of these pregnancies in a differentiated perinatal supportcenter with connection to the surgical pediatric service allows a quick orientation in order toimprove the prognosis of these newborns.
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"Hydrogen Fuel Cell on a Helicopter: A System Engineering Approach." Master's thesis, 2016. http://hdl.handle.net/2286/R.I.38685.
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abstract: Hydrogen fuel cells have been previously investigated as a viable replacement to traditional gas turbine auxiliary power unit onboard fixed wing commercial jets. However, so far no study has attempted to extend their applicability to rotary wing aircrafts. To aid in the advancement of such innovative technologies, a holistic technical approach is required to ensure risk reduction and cost effectiveness throughout the product lifecycle. This paper will evaluate the feasibility of replacing a gas turbine auxiliary power unit on a helicopter with a direct hydrogen, air breathing, proton exchange membrane fuel cell, all while emphasizing a system engineering approach that utilize a specialized set of tools and artifacts.<br>Dissertation/Thesis<br>Masters Thesis Engineering 2016
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Chu, Chung-Ping, and 朱中平. "The effect of MAS provision and external oversight on auditors'' independence- an experimental approach." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/31482969026545490325.
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碩士<br>東吳大學<br>會計學系<br>91<br>ABSTRACT
This thesis examines the effects of provision of management advisory services (MAS) to audit clients and implementation of external oversight mechanism on auditor independence. Unlike most of prior empirical research, which employed questionnaire survey, the current study adopts an experimental approach to examine issues related to auditor independence.
Adopting a 2 (provision of MAS versus no provision of MAS) x 2 (external oversight versus no external oversight) between-subjects design, this study recruited auditors with average experience length of 6.2 years from Big 5 firms as subjects. Subjects were asked to judge the appropriateness of an audit client’s accounting treatment on provision of allowance for bad debts. Subjects were also asked to decide the amount for allowance for bad debts.
The experimental results based on 53 subjects are as follows. First, auditors providing MAS to their audit clients were found to decide a significantly smaller amount of allowance for bad debts than auditors without providing MAS, though they were not significantly different in judging the appropriateness of accounting treatment by the audit client. The association between the amount of allowance for bad debts and the felt pressure arising from the audit client was negative. Taken together, these findings suggest the auditors in this experiment were capable of detecting the errors in accounting treatment, and provision of MAS to an audit client may increase the perceived pressure. This increased pressure may induce them to decide a less conservative amount of allowance for bad debts. Second, implementing external oversight mechanism similar to that proposed by the Sarbanes-Oxley Act had an effect on auditors’ decision on the amount of allowance for bad debts in an expected direction. Limitations and implications of this study are offered.
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Zambare, Hrishikesh B. "Nonlinear design, modeling and simulation of magneto rheological suspension: a control system and systems engineering approach." Thesis, 2017. https://doi.org/10.7912/C2GW8S.
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Indiana University-Purdue University Indianapolis (IUPUI)<br>Suspension has been the most important subsystem of the vehicle viewed as a system. The ride comfort and vehicle handling performance are affected by the suspension design. Automotive technology has been continuously incorporating developments over the past few decades to provide the end users with a better comfort of driving. Multi-objective optimization of MR damper with objective function of maximizing damping force generated by MR damper with the geometrical parametric constraint function is achieved in this research using pattern search optimization technique.
Research focuses on design, modeling, and simulation of active suspension using non-linear theory of the Magneto-Rheological (MR) damper with consideration of the hysteresis behavior for a quarter car model. The research is based on the assumption that each wheel experiences same disturbance excitation. Hysteresis is analyzed using Bingham, Dahl’s, and Bouc-Wen models. Research includes simulation of passive, Bingham, Dahl, and Bouc-wen models. Modeled systems are analyzed for the six road profiles, including road type C according to international standards ISO/TC108/SC2N67. Furthermore, the comparative study of the models for the highest comfort with less overshoot and settling time of vehicle sprung mass are executed. The Bouc-Wen model is 36.91 percent more comfortable than passive suspension in terms of damping force requirements and has a 26.16 percent less overshoot, and 88.31 percent less settling time. The simulation of the Bouc-Wen model yields a damping force requirement of 2003 N which is 97.63 percent in agreement with analytically calculated damping force generated by MR damper. PID controller implementation has improved the overshoot response of Bouc-Wen model in the range of 17.89 percent-81.96 percent for the different road profiles considered in this research without compromising on the settling time of system. PID controller implementation further improves the passenger comfort and vehicle ride handling capabilities.
The interdisciplinary approach of systems engineering principles for the suspension design provides unique edge to this research. Classical systems engineering tools and MBSE approach are applied in the design of the MR damper. Requirement traceability successfully validates the optimized MR damper.
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(7039955), Casey Allen Shull. "ALGORITHM TO DEVELOP A MODEL PROVIDING SECURITY AND SUSTAINABILITY FOR THE U.S. INFRASTRUCTURE BY PROVIDING INCREMENTAL ELECTRICAL RESTORATION AFTER BLACKOUT." Thesis, 2019.
Find full textAbstract:
<p>Is North America vulnerable to widespread electrical
blackout from natural or man-made disasters? Yes. Are electric utilities and
critical infrastructure (CI) operators prepared to maintain CI operations such
as, hospitals, sewage lift stations, food, water, police stations etc., after
electrical blackout to maintain National security and sustainability? No. Why? Requirements
to prioritize electrical restoration to CI do not exist as a requirement or
regulation for electrical distribution operators. Thus, the CI operators cannot
maintain services to the public without electricity that provides power for the
critical services to function. The problem is that electric utilities are not
required to develop or deploy a prioritized systematic plan or procedure to
decrease the duration of electrical outage, commonly referred to as blackout. The
consequence of local blackout to CI can be multi-billion-dollar financial
losses and loss of life for a single outage event attributed to the duration of
blackout. This study utilized the review of authoritative literature to answer
the question: “Can a plan be developed to decrease the duration of electrical
outage to critical infrastructure”. The literature revealed that electric
utilities are not required to prioritize electrical restoration efforts and do
not have plans available to deploy minimizing the duration of blackout to CI.
Thus, this study developed a plan and subsequent model using Model Based System
Engineering (MBSE) to decrease the duration of blackout by providing incremental
electrical service to CI.</p>