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Anderson, Brian Eric. "Unitary Transformations in a Large Hilbert Space." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/305872.
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Quantum systems with Hilbert space dimension greater than two (qudits) provide an alternative to qubits as carriers of quantum information, and may prove advantageous for quantum information tasks if good laboratory tools for qudit manipulation and readout can be developed. We have implemented a protocol for arbitrary unitary transformations in the 16 dimensional hyperfine ground manifold of Cesium 133 atoms, using phase modulated rf and microwave magnetic fields to drive the atomic evolution. Our phase modulation waveforms are designed numerically using a variant of the highly efficient GRAPE algorithm. The fidelity of the resulting transformations is verified experimentally through randomized benchmarking, which indicates an average fidelity better than 97% across a sample of random unitaries.
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Martin, Steven. "Scalable Data Transformations for Low-Latency Large-Scale Data Analysis." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366108187.
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Martin, Steven A. "Culture of Control and its Relationship to Successful Large Scale Agile Transformations." Franklin University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=frank1620731439153882.
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Chick, Jane. "The large pavement at Qasr el-Lebia in Cyrenaica : episodes, narratives and transformations." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/49749/.
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The main focus of this thesis is the large mosaic pavement in the East Church complex at Qasr el-Lebia in Cyrenaica, Libya. It sets out to establish whether the fifty panels which comprise the pavement constitute a coherent programme. In order to do that the literature is reviewed, the site is set in its Cyrenaican context in terms of its history, its physical geography, its settlement patterns and its principal Christian buildings. The dating of the mosaic is considered and a detailed panel-bypanel catalogue of the images is offered. An iconographical study looks closely at groups of panels and correspondences between panels with a view to establishing whether they were entirely independent, one of another, or whether they constituted an overall programme. Having concluded that there are, indeed, significant levels of coherence, the study addresses a number of apparent discrepancies by looking at examples - in literature, sculpture and architecture – of a late antique predilection for disjunctions, puzzles and puns. After this wide-ranging review, the thesis returns to the most immediate context for the floor – its architectural setting. Inconclusive without further excavation, it nevertheless explores the possibility, based largely on the architectural evidence, that the pavement belonged to the ground floor of an episcopium. Finally, the study proposes an overall programme for the pavement and examines how the architecture constrained, and how the layout and iconography of the floor contributed to, a physical experience of the space in what may have been the consignatorium of a baptistery.
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Jackson, George. "Phase separation in solutions of large spherical particles." Thesis, University of Oxford, 1986. http://ora.ox.ac.uk/objects/uuid:9db7de2e-b365-4433-8e14-746efb32c070.
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The effect of large size ratios of solute to solvent on the critical properties and phase behaviour of binary mixtures of spherical particles is investigated using an "augmented van der Waals" equation of state. The equation used is essentially a van der Waals equation with an improved hard sphere repulsive term. Molecular dynamics and constant-pressure Monte Carlo simulations of binary mixtures of hard spheres with different diameter ratios and mole fractions are undertaken to check the adequacy of the hard sphere equation. Good agreement is found, even for systems with large differences in size. Furthermore, many of the hard sphere mixtures exhibited a transition from a fluid to a solid phase at high densities. Phase boundaries are calculated for model mixtures comprising spheres of different sizes between which there are long-ranged attractive forces. Particular attention is paid to the case in which the ratio of sizes is infinite. The systems show a wide variety of behaviour that includes liquid-liquid and gas-gas immiscibility, and the formation of negative azeotropes. Calculations investigating the effect of different attractive interactions between the small and large spheres show that as the magnitude of this interaction is increased, liquid-liquid immiscibility becomes the dominant feature of the phase diagram at moderate temperatures. The extent of liquid-liquid coexistence is greatest at large size differences. These model systems are shown to reproduce some of the behaviour of aqueous solutions of surfactants if it is assumed that the large spheres are models of the micelles and the small spheres models of the solvent molecules. The properties of binary lattice mixtures of bifunctional molecules whose ends are chosen to mimic surfactant and solvent molecules are also briefly investigated, to determine the effect of the asymmetric surfactant molecule on the phase separation. Closed-loops emerge in the phase diagrams as the surfactant character of one of the species is increased.
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Daniel, Gwendal. "Efficient persistence, query, and transformation of large models." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2017. http://www.theses.fr/2017IMTA0049/document.
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L’Ingénierie Dirigée par les Modèles (IDM) est une méthode de développement logicielle ayant pour but d’améliorer la productivité et la qualité logicielle en utilisant les modèles comme artefacts de premiers plans durant le processus développement. Dans cette approche, les modèles sont typiquement utilisés pour représenter des vues abstraites d’un système, manipuler des données, valider des propriétés, et sont finalement transformés en ressources applicatives (code, documentation, tests, etc). Bien que les techniques d’IDM aient montré des résultats positifs lors de leurs intégrations dans des processus industriels, les études montrent que la mise à l’échelle des solutions existantes est un des freins majeurs à l’adoption de l’IDM dans l’industrie. Ces problématiques sont particulièrement importantes dans le cadre d’approches génératives, qui nécessitent des techniques efficaces de stockage, requêtage, et transformation de grands modèles typiquement construits dans un contexte mono-utilisateur. Plusieurs solutions de persistance, requêtage, et transformations basées sur des bases de données relationnelles ou NoSQL ont été proposées pour améliorer le passage à l’échelle, mais ces dernières sont souvent basées sur une seule sérialisation model/base de données, adaptée à une activité de modélisation particulière, mais peu efficace pour d’autres cas d’utilisation. Par exemple, une sérialisation en graphe est optimisée pour calculer des chemins de navigations complexes,mais n’est pas adaptée pour accéder à des valeurs atomiques de manière répétée. De plus, les frameworks de modélisations existants ont été initialement développés pour gérer des activités simples, et leurs APIs n’ont pas évolué pour gérer les modèles de grande taille, limitant les performances des outils actuels. Dans cette thèse nous présentons une nouvelle infrastructure de modélisation ayant pour but de résoudre les problèmes de passage à l’échelle en proposant (i) un framework de persistance permettant de choisir la représentation bas niveau la plus adaptée à un cas d’utilisation, (ii) une solution de requêtage efficace qui délègue les navigations complexes à la base de données stockant le modèle,bénéficiant de ses optimisations bas niveau et améliorant significativement les performances en terme de temps d’exécution et consommation mémoire, et (iii) une approche de transformation de modèles qui calcule directement les transformations au niveau de la base de données. Nos solutions sont construites en utilisant des standards OMG tels que UML et OCL, et sont intégrées dans les solutions de modélisations majeures telles que ATL ou EMFThe Model Driven Engineering (MDE) paradigm is a softwaredevelopment method that aims to improve productivity and software quality by using models as primary artifacts in all the aspects of software engineering processes. In this approach, models are typically used to represent abstract views of a system, manipulate data, validate properties, and are finally transformed to application artifacts (code, documentation, tests, etc). Among other MDE-based approaches, automatic model generation processes such as Model Driven Reverse Engineering are a family of approaches that rely on existing modeling techniques and languages to automatically create and validate models representing existing artifact. Model extraction tasks are typically performed by a modeler, and produce a set of views that ease the understanding of the system under study. While MDE techniques have shown positive results when integrated in industrial processes, the existing studies also report that scalability of current solutions is one of the key issues that prevent a wider adoption of MDE techniques in the industry. This isparticularly true in the context of generative approaches, that require efficient techniques to store, query, and transform very large models typically built in a single-user context. Several persistence, query, and transformation solutions based on relational and NoSQL databases have been proposed to achieve scalability, but they often rely on a single model-to-database mapping, which suits a specific modeling activity, but may not be optimized for other use cases. For example a graph-based representation is optimized to compute complex navigation paths, but may not be the best solution for repeated atomic accesses. In addition, low-level modeling framework were originally developed to handle simple modeling activities (such as manual model edition), and their APIs have not evolved to handle large models, limiting the benefits of advance storage mechanisms. In this thesis we present a novel modeling infrastructure that aims to tackle scalability issues by providing (i) a new persistence framework that allows to choose the appropriate model-to-database mapping according to a given modeling scenario, (ii) an efficient query approach that delegates complex computation to the underlying database, benefiting of its native optimization and reducing drastically memory consumption and execution time, and (iii) a model transformation solution that directly computes transformations in the database. Our solutions are built on top of OMG standards such as UML and OCL, and are integrated with the de-facto standard modeling solutions such as EMF and ATL
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Choucair, Israa. "A Four-dimensional Approach to Finite Element Method for the Large Transformations of Materials." Thesis, Troyes, 2021. http://www.theses.fr/2021TROY0025.
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Une description spatio-temporelle des grandes déformations thermomécaniques des milieux continus est développée: l'utilisation d'une telle approche quadridimensionnelle garantit la covariance générale des modèles proposés. Les équations de conservation sont écrites dans ce contexte et un modèle constitutif est dérivé pour les transformations réversibles. Nous utilisons des opérateurs de projection pour obtenir les composantes spatiales et temporelles des équations régissant 4D et pour interpréter les résultats. Nous proposons ensuite une formulation faible du problème ainsi que sa discrétisation par éléments finis, à résoudre pour les grandes déformations d'un solide. L'avantage de cette description est que l'intégration sur l'espace et le temps se fait en une seule étape. Nous discutons pourquoi le système de coordonnées convectives 4D est intéressant pour résoudre le problème. Enfin, nous illustrons la démarche par des exemples analytiques et résolvons numériquement des problèmes thermomécaniques avec une implémentation sur le logiciel FEniCSA space-time description of the finite transformations of thermo-mechanical continua is developed: the use of such a four-dimensional approach guarantees the general covariance of the proposed models. The conservation equations are written in this context and a constitutive model is derived for reversible transformations. We use projection operators to obtain the space and time components of the 4D governing equations and to interpret the results. We next propose a weak formulation of the problem along with its finite-element discretization, to be solved for the finite transformations of a solid. The advantage of this description is that the integration on space and time is performed in one step. We discuss why the 4D convective coordinate system is of interest to solve the problem. Finally, we illustrate the approach with analytical examples and solve thermo-mechanical problems numerically with an implementation on FEniCS software
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Storå, Erik. "Towards scaled agility : A case study on successfully initiating agile transformations at large banks." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279610.
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Large banks are facing challenges from a new regulatory and competitive landscape which have led to 30 % of banks adopting agile using the Scaled agile framework (SAFe). The transformation process towards agile is complex and has led to a change process covering aspects such as a product development, leadership and organizational design. Currently scientific knowledge on how to conduct an agile transformation successfully is lacking. The current explorative case study aimed to provide an empirical contribution assisting theory building in the field of scaled agile. Empirical data was collected through thirteen semi structured interviews, totaling ten hours combined with ten ethnographic observations spanning 34 hours. The subsequent findings identified four approaches to scaling agile combined with eight aspects of scaled agility providing a new depth regarding how to apply them and what to achieve. The four approaches identified were: creating a virtual organization, standardization of agile methods, unifying around one portfolio and, changing towards an agile mindset. The eight aspects include strategic agility, payoff agility, business agility, product agility, agile organization, tools agility, people agility, and organizational culture. The eight aspects where synthesized into a framework from the fields of agile software development, agile portfolio management, Scrum, SAFe, Lean, New product development, Lean product development, aspects of change, emergent change models, organizational design, resistance to change, and organizational culture. In addition, insights from previous agile transformations was conducted by researching benchmark studies of the bank ING. The results indicated an initial successful implementation as the interviewees expressed joy in working with the new methods. Furthermore an effective use of all four major approaches to scaling agile was evident. The results showed that the scope of the transformation kept growing and was managed through iterative improvements. Integration of already agile parts of the organization such as projects was enabled, and initial changes in leadership and delegation as well as new roles were managed. However some struggles remained regarding product development which could not be conducted in a fully agile way due to large releases and a regulated environment. In addition dependencies between different teams limited the creation of autonomous teams capable of delivering end to end. Furthermore as the work was visualized the amount spent on non value adding activites such as preparing low value task could be avoided, which however required extensive refinement. The focus on the new methods furthermore led to less time spent with customers. One challenge that emerged was that the virtual organization started to interfere with the traditional organization. A shift in power from hierarchies to teams took place. Aspects such as recruitment and rewards remained in the old structure highlighting a double organizational culture. This provides some uncertanty regarding further adaptions in the long run. The study has provided an empirical contribution as well as conceptualization of the approaches and aspects of scaled agility which provides hypothesis that assist future theory building. In addition the implications showed to be noteworthy from as sustainability pespective by enabling ecnomic benefits such as efficency and new IT-infrastrucutre combined with good jobs and limited enviromental impacts. To validate the results more studies could be performed at other companies, other parts of banks as well as more extensive data collection such as quantitative approaces and long term observations.Stora banker möter utmaningar från ett nya regleringar och ökad konkurrens som har lett till att 30% av bankerna har infört agila metoder genom Scaled agile framework (SAFe). Omvandlingsprocessen mot agile är komplex och leder till en förändringsprocess som täcker aspekter som produktutveckling, ledarskap och organisationsdesign och som för närvarande saknar vetenskaplig kunskap om hur den ska bedrivas framgångsrikt. Denna undersökande fallstudie syftade till att tillhandahålla ett empiriskt bidrag som hjälper till med teoriuppbyggnad inom området skalad agile genom hypotesformulering. Empiriska data samlades in genom tretton halvstrukturerade intervjuer, sammanlagt tio timmar, i kombination med tio etnografiska observationer som sträckte sig över 34 timmar. Från fynden identifierades fyra metoder för att skala agile i kombination med åtta aspekter av skalad agilitet som ger ett nytt djup angående tillämpningar av dem och vad man ska uppnå. De fyra identifierade tillvägagångssätten är: skapandet av en virtuell organisation, standardisering av agila metoder, förenande kring en portfölj och förändring mot ett agilt tankesätt. De åtta aspekterna inkluderar strategisk agility, payoff agility, business agility, produkt agility, agile organisation, tools agility, resurs agility och organisationskultur. De åtta aspekterna av scalad agilitet var syntetiserade till ett ramverk baserat på ämnesområdena agil programvaruutveckling, agil portföljhantering, Scrum, SAFe, Lean, New product development, Lean produktutveckling, aspekter av förändring, framväxande förändringsmodeller, organisationsdesign, motstånd mot förändring och organisatorisk kultur. Dessutom samlades insikter från tidigare agila transformationer på banker genom att undersöka en benchmarkstudie av banken ING. Resultaten visade på initiala framgångar i genomförande då intervjuobjekten uttryckte at de metoderna var givande att arbeta med. En framgångsrik användning av alla fyra huvudsakliga tillvägagångssätt för att scala agila metoder observerades. Resultaten visade att den planerade omfattningen av omvandlingen ökade under processens gång och hanterades genom iterativa förbättringar. Integrering av redan agila delar av organisationen som projekt möjliggjordes och initiala förändringar i ledarskap och delegering liksom nya roller hanterades. Vissa utmaningar återstod emellertid som berörde produktutveckling som inte kunde genomföras på ett fullständigt agilt sätt på grund av stora leveranser och den starkt reglerade miljön. Dessutom utgjorde beroenden mellan olika team en utmaning för införandet av autonoma end-to-end team. Eftersom arbetet visualiserades kunde man också undvika mängden arbete på aktiviteter som inte tillförde värde. Förberedandet av dessa uppgifter krävde omfattande tidskrävande förfining. En nackdel med det ökade arbetet mellan olika avdelningar var att dialogen med kunder minskade. En utmaning med den virtuella organisationen var att den störde den traditionella organisationen. Till exempel genom att fördela makt från tidigare hierarkier till nya team. Dessutom kvarstod aspekter som anställningar och belöningar inom den traditionella strukturen vilket ledde till en dubbel organisationskultur. Detta kan ge en viss osäkerhet när det gäller ytterligare anpassningar på lång sikt. Studien har gett ett empiriskt bidrag till agile såväl som en konceptualisering av såväl tillvägagångssätt som olika aspekter av skalad agilitet inför framtida teoriskapande. Dessutom visade sig den agila transformation vara positiv utifrån ett hållbarhetsperspektiv genom att möjliggöra ekonomiska fördelar som effektivitet och ny IT-infrastruktur kombinerat med ansenliga arbetsvillkor och icke ökande miljöpåverkan. För att validera resultaten kan fler studier behöva utföras hos andra företag, andra delar av banker, mer omfattande datainsamling inkluderande kvantitativa metoder och mera långsiktiga observationer.
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Oueslati, Jamel. "Contribution à l'étude numérique des grandes transformations élastoplastiques." Paris 6, 1986. http://www.theses.fr/1986PA066132.
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On cherche à étudier aux grandes transformations des moyens de calcul permettant de traiter des problèmes généraux d'équilibre élastoplastiques de structures planes ou axosymétriques; ces structures peuvent subir de grands déplacements, de grandes rotations et de grandes déformations plastiques, les déformations élastiques étant supposées petites. On se limite au cas du matériau initialement isotrope, avec écrouissage isotrope ou cinématique.
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Phadke, Nandan Neelkanth. "OPTIMIZATIONS ON FINITE THREE DIMENSIONAL LARGE EDDY SIMULATIONS." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1431084092.
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Zhang, Lei. "Sur une approche isogéométrique pour problèmes multi-champs couplés en grandes transformations." Thesis, Ecole centrale de Marseille, 2016. http://www.theses.fr/2016ECDM0012/document.
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La méthode isogéométrique (IGA) récemment proposée en tant que méthode numérique générique offre de réelles perspectives dans l’unification des modèles géométriques et computationnel. La méthode isogéométrique est intiment liée à la méthode des éléments finis (FEM) étant donné que la méthode est basée sur le même cadre variationnel. Cette méthode a montré dans de nombreuses circonstances de très bonne qualités numériques notamment avec des maillages grossiers (précision numérique, capacité à supporter de grandes déformations…). Notre objectif final dans ce travail est de fournir un environnement de base, numérique et logiciel, pour la simulation de problèmes à champs et physiques multiples pour des pièces élastomériques de type industriel. Dans ce contexte, les points numériques à développer pour l’IGA sont le traitement de l’incompressibilité et le caractère multi-champs du problème thermique dans la formulation de Galerkin. Ainsi dans ce travail nous proposons en premier, un paradigme objet de l’IGA intégré au sein d’une architecture orientée objet en Java, initialement con?ue pour résoudre des problèmes multi-champs couplés en transformations finies. L’approche proposée s’appuie pleinement sur le contexte variationnel existant dans le code dans le cadre des éléments finis pour réduire les développements pour MEF et IGA (une formulation développée en IGA tourne en MEF et vice versa). Dans un second temps, nous avons étudié le problème de l’incompressibilité pour notamment réduire le verrouillage numérique existant toujours sur l’IGA standard. Par un souci de simplicité, nous adoptons des formulations mixtes à 2 champs (déplacement/pression). Afin d’essayer de satisfaire la condition inf-sup en relachant la contrainte sur le déplacement, nous avons développé deux idées de la littérature (naturelle en NURBS) qui consiste à soit dupliquer une fois les n?uds intérieurs du patch des déplacements ou subdiviser les éléments du patch des déplacements. Nous avons étendu ce type d’éléments aux transformations finies. Enfin, et de manière originale, nous avons adopté la même stratégie pour les problèmes à 2-champs pour la thermomécanique. Différentes simulations à petites et grandes déformations confirment le potentiel de l’approche. Enfin, nous évaluons l’ensemble sur un modèle quasi-incompressible thermo-visco-élastique de type Zener sur des éprouvettes classiques dans un contexte physique complexeRecently proposed as a general purpose numerical method, the Isogeometric Analysis (IGA) offers great perspective to bridge the gap between CAD and CAE. The IGA is closely related to the finite element method (FEM) as the method is based on the same variational framework. Moreover, this method has shown in many circumstances to be have a better accuracy than the FEM (large mesh distortions…). Our final aim in this work is to simulate complex multiphysics problems for elastomers industrial parts. As matter of fact, the two main numerical issues in this context is the incompressibility/quasi-incompressibility of the material and the thermochemical coupling in Galerkin formulations. First, we propose, a programming paradigm of the IGA in an existing Java object-oriented hierarchy initially designed for solving multi-fields coupled problems at finite strains. We develop an approach that fully take benefit of the original architecture to reduce developments for both FEM and IGA (one problem developed in FEM can be run in IGA and vice versa). Second, we investigate volumetric locking issues persisting for low order NURBS element observed with standard displacement formulation as finite elements. To cure the problem, we adopt two-fields mixed formulation (displacement/pressure) for the sake of simplicity and target at assessing different discretizations in stability (inf-sup condition). The basic idea is to first to increase the internal knot’s multiplicity or to subdivide the patch for displacements. These ideas that are directly inspired from patches properties, have been found in the literature for the Stokes problem and extended to large strain in solid mechanics. The comparison between the two-fields mixed formulation and a strain projection method is lead at small and large strains. At last, we originally adopt a similar strategy for thermomechanical problem at small and large strains. In the context two-fields formulation, displacement/temperature, the LBB stability condition must be fulfilled to guaranty stability. Thus, we investigate the choices of patches for two-fields formulation displacement/temperature fields for IGA applied to thermoelasticity. Several numerical results for thermomechanical problems at small and finite strains, linear and nonlinear have been presented. At last, an incompressible viscous thermo-hyperelastic model is evaluated in the IGA framework with the proposed approach
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Corsini, Niccolo. "Pressure-induced structural transformations in nanomaterials : towards high accuracy large length- and time-scale simulations." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/42247.
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The study of pressure-induced structural transformations in nanomaterials is both of fundamental and technological importance. Accurate simulations of these transformations are challenging because large length- and time-scales have to be simulated to make contact with experiments whilst retaining the atomic detail for a faithful description. In this thesis, both classical and quantum mechanical techniques are used to model pressure-induced structural transformations in realistic Si, Ge and CdS nanocrystals and comparison made to experiment where possible. We implement an electronic enthalpy method within the linear-scaling density-functional theory ONETEP code and, after introducing an approach for calibrating the volume definition, investigate the size-dependent pressure-induced amorphisation and polyamorphic transformations in hydrogenated Si and Ge nanocrystals. For the latter, we elucidate the surface-induced amorphisation and the new high-density amorphous metallic Ge phase observed experimentally. We combine this method with the projector-augmented wave and time-dependent density-functional theory methods to study the size and ligand dependence of deformation and optoelectronic properties of CdS nanocrystals with pressure. We develop a novel classical parametrisation for the simulation of bare and ligated CdS nanocrystals immersed in a pressure-transmitting medium and investigate their transformation under pressure using classical molecular dynamics and the metadynamics method for accelerating rare events. The resulting polymorphic transformation and pressure-induced amorphisation are analysed in detail.
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Rosenberg, Paul Adam. "The pattern of large-scale history : Hegel's system and its political transformations in Marx and Postmodernism." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621367.
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Boucard, Pierre-Alain. "Approche à grand incrément de temps en grandes transformations." Cachan, Ecole normale supérieure, 1996. http://www.theses.fr/1996DENS0006.
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L'étude des problèmes statiques en grandes transformations suppose la résolution d'équations non linéaires ou les non linéarités sont d'origine physique et géométrique. Les méthodes usuelles de calcul sont basées sur la méthode incrémentale en sollicitation et nécessitent l'utilisation de techniques de type Riks ou Crisfield pour franchir les points d'instabilité. L'approche utilisée dans ce travail s'en différencie sur deux points. Tout d'abord nous exploitons une reformulation matérielle du problème en grandes transformations qui, utilisant des grandeurs tournées par la rotation locale, permet d'écrire le comportement et l'équilibre dans un espace unique de représentation. La formulation ainsi obtenue est formellement très proche d'un problème de type petites perturbations. Sur cette formulation, une approche a grand incrément de temps est développée: c'est une méthode non incrémentale qui traite de façon itérative l'ensemble de l'intervalle d'étude sans hypothèse a priori et qui ne nécessite pas le recours a des méthodes de type Riks ou Crisfield lorsque celui-ci inclut un point critique. Les premiers développements donnes dans cette étude ont été menés sur les arcs plans élastiques. La reformulation matérielle en théorie des poutres et l'approche à grand incrément de temps qui lui est associée y sont détaillées. Ce cadre nous sert de banc d'essai pour mettre en évidence et résoudre les problèmes informatiques et numériques poses par cette nouvelle approche. Sur quelques exemples de la littérature traitant du calcul du post flambement, nous illustrons le fonctionnement de la méthode, et nous la comparons avec les démarches classiques. Pour ces exemples, la réponse post critique est guidée par l'introduction d'une imperfection. Le problème est résolu globalement sur tout l'intervalle d'étude, ou sur deux sous-intervalles séparés par le point critique, ne nécessitant chacun que peu d'itérations donc peu de problèmes globaux à résoudre. Cette première étude est donc une étude de faisabilité qui montre les performances de la méthode dans un cadre simplifie et permet d'envisager des extensions au cadre tridimensionnel et à des modèles de matériaux en grandes transformations
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Adjaout, Abdelhamid. "Validation des mesures de gravité en mer : détermination du géoïde gravimétrique au large du Japon et détection du courant Kuroshio." Observatoire de Paris (1667-....), 1994. https://theses.hal.science/tel-01958570.
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Le but de cette thèse est la validation des données gravimétriques marines. Le premier chapitre est une revue des principes de la mesure de gravité en mer, des différents types d'appareils utilisés et des sources d'erreurs. Un modèle de validation et d'ajustement des données fondé sur l'examen et la minimisation des différences de mesures aux points de croisement (à l'intérieur d'une croisière et/ou entre diverses croisières), est proposé au deuxième chapitre. Le troisième chapitre est l'application de ce modèle aux données gravimétriques au large du Japon. Plus d'un demi-million de mesures de 173 croisières ont ainsi été ajustées. Un géoïde gravimétrique est ensuite calculé par trois méthodes : collocation, formule de stokes et transformation de Fourier puis comparé avec les travaux antérieurs. Afin d'estimer la précision de notre géoïde gravimétrique, un nouveau géoïde altimétrique a été calculé à partir d'un an de données du satellite Topex/Poséidon, d'un an du satellite Geosat et un cycle de mesures du satellite ERS-1. Le dernier chapitre traite de la détection de la signature du courant Kuroshio à partir de la différence entre le géoïde gravimétrique et la surface instantanée de l'océan sous les traces de Topex/Poséidon. La mise en évidence du courant et de ses variations saisonnières est meilleure qu'à partir des précédents modèles.
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Benrabah, Imed-Eddine. "Développement d’alliages métalliques à gradient de composition pour l’exploration combinatoire des microstructures." Thesis, Université Grenoble Alpes, 2021. http://www.theses.fr/2021GRALI005.
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La transformation de l'austénite en ferrite dans les aciers présente un intérêt considérable pour le contrôle des propriétés finales des aciers, en particulier des aciers à haute résistance (AHSS) tels que l'acier dual phase (DP). Malgré les efforts considérables déployés pour comprendre les mécanismes qui contrôlent la cinétique de formation de la ferrite, le rôle des éléments substitutionnels pendant la croissance de la ferrite et leur interaction avec l'interface de migration α/γ restent peu clair. Plusieurs modèles ont été développés pour décrire la cinétique de croissance de la ferrite dans les systèmes ternaires et les systèmes d’ordre supérieur. Les modèles ‘solute drag’ ont été utilisés avec succès pour prédire la cinétique de transformation pour plusieurs solutés et à de nombreuses compositions et températures dans les systèmes ternaires. Cependant, l'extension de ce modèle aux systèmes d'ordre supérieur a mis en évidence un comportement complexe de l'interaction entre les différents éléments interstitiels et substitutionnels à l'interface. La validation des modèles développés nécessite une étude expérimentale de l'effet de la composition et de la température sur la cinétique de croissance. L'objectif de cette contribution est de présenter une méthodologie combinatoire à haut débit complète pour accélérer l'étude l’effet de la concentration des solutés sur la transformation austénite-ferrite. Il convient toutefois de noter que cette nouvelle méthodologie pourrait être utilisée pour étudier toute autre transformation de phase dans tout autre alliage métallique. L'essence de la méthodologie est de fabriquer des matériaux avec des gradients de composition macroscopiques, et d'effectuer des expériences in situ de diffraction des rayons X à haute énergie, résolues dans le temps et dans l'espace, pour enregistrer la cinétique de transformation de phases austénite-ferrite en de nombreux points de l'espace de composition. Des couples de diffusion contenant des gradients de soluté à l'échelle millimétrique et une teneur en carbone presque constante ont été générés en utilisant la présente méthodologie et utilisés pour étudier la cinétique de croissance de la ferrite à des températures intercritiques en utilisant des expériences in situ de diffraction des rayons X à haute énergie. Pendant 4 jours d'expériences, plus de 1500 cinétiques ont été mesurées pour différentes compositions et à différentes températures. Cet ensemble de données d'une taille sans précédent a été utilisé pour valider une version modifiée du modèle ‘three-jump solute drag’ pour les systèmes ternaires et quaternaires. Les calculs du modèle correspondent parfaitement à la cinétique de transformation expérimentale à toutes les températures étudiées et sur presque toutes les plages de composition étudiées de Si, Cr, Mn, Ni et Mo, contrairement aux résultats des modèles de para-équilibre (PE) et de partitionnement négligeable à l'équilibre local (LENP). En outre, il a été démontré que l'étalonnage des paramètres thermodynamiques dans les systèmes ternaires reste valable dans les systèmes quaternaires, ouvrant la voie à la modélisation de la transformation dans les systèmes d'ordre supérieurThe transformation of austenite into ferrite in steels is of considerable interest in controlling the final properties of steels, in particular Advanced High-Strength Steels (AHSS) such as Dual Phase (DP) steel. Despite tremendous efforts in understanding the mechanisms controlling ferrite formation, the role of substitutional elements during ferrite growth and their interaction with the migrating α/γ interface remain unclear. Several models have been developed to describe ferrite growth kinetics in ternary and higher systems. The solute drag based models have been successfully used to predict kinetics for multiple substitutional solutes, compositions and temperatures in ternary systems. However, the extension of this model to higher order systems highlighted a complex behavior of the interaction between the different interstitial and substitutional elements at the interface. Validation of the developed models requires an experimental study of the effect of both composition and temperature on growth kinetics. The aim of this contribution is to present a complete combinatorial high-throughput methodology to accelerate the investigation of the dependency of ferrite growth kinetics on substitutional composition in alloy steels. It is noteworthy, however, that this new methodology could be used to study any other phase transformation in any other metallic alloy. The essence of the methodology is to fabricate materials with macroscopic composition gradients, and to perform time- and space-resolved in situ high-energy X-ray diffraction experiments to gather the austenite-to-ferrite phase transformation kinetics in many points of the compositional space. Diffusion couples containing millimeter-scale solute gradients and an almost constant carbon content were generated using the present methodology and used to study ferrite growth kinetics at inter-critical temperatures using in-situ high-energy X-ray diffraction experiments. During 4 days of experiments, more than 1500 kinetics were gathered for different compositions and at different temperatures. This dataset of unprecedented size was used validate a modified version of the three-jump solute drag model for both ternary and quaternary systems. The model calculations matched experimental transformation kinetics at all investigated temperatures and over almost all the investigated composition ranges of Si, Cr, Mn, Ni, and Mo, contrary to results from para-equilibrium (PE) and local equilibrium negligible partitioning (LENP) models. Additionally, it was demonstrated that the calibration of thermodynamic parameters in ternary systems held true in quaternary systems, paving the way towards modeling of the transformation in higher-order systems
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Boisly, Martin. "Modellierung des Materialverhaltens Magnetorheologischer Fluide unter Verwendung der Fourier-Transformations Rheologie." Doctoral thesis, Logos Verlag Berlin GmbH, 2017. https://tud.qucosa.de/id/qucosa%3A32282.
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In dieser Dissertation wird das viskoplastische Schubverhalten eines magnetorheologischen Fluids (MRF) modelliert. Mithilfe eines phänomenologischen Modellierungsansatzes auf Basis nichtlinearer rheologischer Elemente können die gemessenen Fließkurven sowie Speicher- und Verlustmoduli abgebildet werden. Ein MRF ist ein Material mit fest-flüssig Übergang. Es besitzt von einem Magnetfeld abhängige Materialeigenschaften. Um diese beschreiben zu können, wird zunächst eine phänomenologische Stoffklassifizierung eingeführt. Auf deren Grundlage teilen sich Stoffe allgemein in Flüssigkeiten, Festkörper und Materialien mit fest-flüssig Übergang auf. Zur Beschreibung des Materialverhaltens von MRF werden drei viskoplastische Modelle formuliert und gegenübergestellt. Zur Identifikation der Materialparameter wird eine Identifikationsstrategie auf der Grundlage charakteristischer Punkte entwickelt. Charakteristische Punkte sind exklusive Punkte von Materialfunktionen, die analytisch beschrieben und ohne Weiteres experimentell ermittelt werden können. Analytische Ausdrücke für charakteristische Punkte der Speicher- und Verlustmoduli werden über das Analogieprinzip unter Verwendung von Lissajous Diagrammen abgeleitet. Infolgedessen können die Materialparameter durch das Auswerten algebraischer Zusammenhänge identifiziert werden, ohne nichtlineare Optimierungsverfahren anwenden zu müssen. Hierbei stellt die Fließspannung einen signifikanten Materialparameter dar. Deswegen werden die Standardverfahren zur Bestimmung der Fließspannung auf rheologische
Modelle angewendet und bewertet.
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KHAN, AREEBA ZAMAN, and SOPHIE ÅSTRÖM. "Large-Scale Agile Transformation : A Case Study Conducted in the Banking Industry with a Focus on Organizational, Managerial, and Cultural Aspects." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299955.
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In today's competitive market, established organizations need to adapt in order to survive. One way to do this is by transforming to agile. Since its origin in the IT industry, the agile approach has been embraced by several different industries. One industry where several major players have undergone an agile transformation is the banking industry, an industry which is characterized by strict regulatory requirements, complex organizational structure, and extensive use of technology. By conducting a case study exploring the agile transformation inside three large banks in Sweden, the motivating factors behind transforming to large-scale agile as well as the key aspects to consider when pursuing an agile transformation have been investigated. The study aims to contribute academically to existing research within the implementation of large-scale agile in the banking industry as well as practically by outlining driving factors and critical considerations when pursuing an agile transformation. An understanding of that the traditional ways of working did not suit today's dynamic market in combination with a need to increase market speed and faster respond to changes in customer needs were found to be the main motivating factors behind why the banks decided to transform to an agile approach. The theoretical and empirical findings led to the identification of five aspects to consider when transforming to large-scale agile. The five aspects are: The role of management, adjusting the method or framework to the organization, the people side of change, knowledge and education as well as the role of HR. Out of these five aspects, our findings indicate that the people side of change is the most challenging one but also the most crucial one to manage in order to accomplish a successful implementation. An active management support throughout the entire transformation journey, change-positive people in positions of leadership, adjustment of chosen methods or frameworks, and adequate funding for knowledge and education were discovered to be critical for a successful transformation. Furthermore, it was discovered that by integrating the HR function early in the transformation, many of the challenges associated with change management and leadership could be mitigated.Etablerade organisationer som verkar på dagens föränderliga marknad behöver bli mer snabbrörliga för att bibehålla sin konkurrenskraft. Ett sätt för organisationer att bli mer snabbrörliga är att implementera agila arbetssätt. Sedan sitt ursprung i IT-branschen har agila arbetssätt implementerats av flera olika branscher. En industri där flera stora aktörer har genomgått en agil transformation är bankindustrin, en teknikintensiv industri med strikta lagkrav och komplexa organisationsstrukturer. Genom att genomföra en fallstudie om den agila transformationen som tre stora banker i Sverige har genomgått kunde de underliggande faktorerna bakom transformationerna till storskaligt agilt arbetssätt samt de viktigaste aspekterna att tänka på vid genomförandet undersökas. Studien syftar till att bidra akademiskt till befintlig forskning inom implementeringen av agila arbetssätt i bankindustrin samt praktiskt genom att beskriva underliggande faktorer samt viktiga aspekter att tänka på vid en agil transformation. En förståelse för att de traditionella arbetssätten inte passar dagens dynamiska marknad i kombination med ett behov av att möta förändrade kundbehov visade sig vara de mest framträdande underliggande faktorerna bakom varför företagen i studien beslutade sig för att implementera agila arbetssätt. Studien resulterade i fem identifierade aspekter att beakta vid implementering av agila arbetssätt: Ledningens roll, anpassning av ramverk till organisation, människans roll i förändringsresan, kunskap och utbildning samt integrering av HR-funktionen. Av dessa fem aspekter visar våra resultat att människans roll i förändringsprocessen är den mest utmanande att hantera men också den mest avgörande för att lyckas uppnå en framgångsrik transformation. Ett aktivt ledningsstöd under hela transformationsresan, förändringspositiva personer i ledande positioner, anpassning av valt ramverk samt tillräcklig finansiering för kunskap och utbildning visade sig vara av central betydelse. Dessutom konstaterades att genom att integrera HR-funktionen i ett tidigt skede av omvandlingen, kunde många av utmaningarna relaterade till förändringsledning och ledarskap mildras.
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Huang, He. "Experimental study of NiTi alloy under shear loading over a large range of strain rates." Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066072.
Full textAbstract:
Ce travail décrit une étude expérimentale sur des tôles en Ni-Ti à température ambiante en cisaillement plan simple, et pour des vitesses de déformation de 10-4 à 103/s. En quasi-statique (10-4-10-2/s), la mesure optique du champ de déplacement est indispensable à cause du faible déplacement (0.3mm). Des essais à vitesse de déformation intermédiaire (10-1-101/s) ont été réalisés avec la Machine MTS modifiée, capable d'aller à 300mm/s. Une caméra rapide est nécessaire pour suivre ces tests. Enfin, des barres de Hopkinson sont utilisées pour les essais à haute vitesse (102-103/s).Les efforts se sont concentrés sur la méthodologie afin d'explorer les limites expérimentales. Au niveau mécanique, des efforts ont été apportés sur la conception des montages des mors pour combiner des exigences contradictoires. Au niveau mesure, des caméras optiques fonctionnant jusqu'à 5M images/s ont été utilisées. La texture des images, la peinture, la lumière, la taille d'élément et l'incertitude sont analysées. De plus, la caméra infrarouge est utilisée pour confirmer l'observation optique sous faibles vitesses de déformation.Finalement, des essais ont été réalisés pour 7 ordres de grandeurs de la vitesse de déformation, avec identification de la relation contrainte-déformation et observation de l'évolution de la bande de transformation. On observe : (i) Une augmentation de la contrainte avec la vitesse de déformation. (ii) Un champ de déformation non homogène, même en faible vitesse, avec une bande à 10 degrés par rapport à la direction de cisaillement. (iii) Deux bandes séparées à haute vitesse (102/s), ce qui indique que la bande de localisation dépend de la vitesse de chargementThis work describes an experimental study on a NiTi alloy at the ambient temperature (Pseudoelastic behavior) under the double in-plane shear loading over strain rates from 10-4 to 103/s. Under quasi-static loadings (10-4-10-2/s), the optical full-field measurement is necessary because of the very small displacement (0.3mm). The intermediate loading rates (10-1-101/s) are realized with a modified MTS machine able to load at 300mm/s. Moreover, a high-speed camera is needed to follow such tests. Finally, the Split Hopkinson bars are used to perform tests at impact loading rates (102-103/s).The main effort has been made on the methodological study to explore the experimental possibility. For the mechanical level, the attention has been paid on the design of the clamping system to cope with the contradictory requirements. For the measuring level, different optical cameras with sampling rate till to 5M frames/second are used. The texture, the painting, the lightening, the element size and the uncertainty are analyzed. Furthermore, an infrared camera was used at lower loading rates to confirm the DIC measurement.The tests are continually performed over 7 decades of the strain rate. The nominal stress-strain curves and the detailed observation of the transformation band evolution are measured. The main findings are as follows: (i) Regular stress increase with the strain rate; (ii) an inhomogeneous strain field under in-plane shear condition, even at very low strain rates, with a band at 10 degrees from the shear direction under lower strain rates. (iii) Two separated bands at the strain rate of 102/s, which suggests that the localized transformation bands are rate dependent
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Alamayreh, Ahmad. "Techniques évoluées d'identification de canal dans les systèmes DSL." Rennes, INSA, 2009. http://www.theses.fr/2009ISAR0011.
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Les systèmes DSL (Digital Subscriber Line) mettent en oeuvre des technologies de communication de données à grande vitesse sur les lignes téléphoniques ordinaires. Les futurs réseaux DSL sont en cours d'élaboration pour tenir compte des demandes croissantes de très hauts débits dans un marché en expansion rapide. Dans l'environnement de communication DSL, la diaphonie entre les paires de cuivre peut atteindre des ordres de grandeur plus grands que tout autre bruit. Elle peut donc être considérée comme le facteur principal de limitation des performances. Les techniques de lutte contre la diaphonie s'appuient habituellement sur la connaissance des caractéristiques du canal pour supprimer les interférences et améliorer les performances globales du système de transmission. Cette aborde le problème de l'estimation de canal dans les systèmes de communication DSL. Une méthode d'estimation de canal aveugle pour les systèmes utilisant la modulation multi-porteuse DMT (Discrete Multi-Tone) est présentée. L'application de cette méthode pour l'élimination des phénomènes de diaphonie est proposée dans les liaisons montantes et descendantes. Dans cette étude, nous traitons les interférences provenant du système DSL lui-même ainsi que celles provenant de systèmes externes. Les performances sont évaluées théoriquement après l'estimation et l'élimination des interférences. Les résultats théoriques son confirmés par des simulations effectuées sur un environnement réaliste DSL et démontrent une nette amélioration dans les débits.
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Dressler, Bernhard. "Modélisation numérique des coques en grandes transformations : mise en oeuvre dans un environnement orienté objet." Châtenay-Malabry, Ecole centrale de Paris, 1997. http://www.theses.fr/1997ECAP0522.
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Ce mémoire est consacré à la dynamique des coques en grandes rotations. La théorie bidimensionnelle des coques est déduite du principe des travaux virtuels d'un milieu continu tridimensionnel en introduisant la cinématique de Mindlin. On obtient un système d'équations non-linéaires qui est linéarise par rapport aux déplacements de la surface moyenne ainsi que par rapport aux paramètres de rotation. La paramétrisation des grandes rotations par le vecteur de rotation est comparée à la paramétrisation directe par la matrice de rotation. En vue d'une discrétisation en éléments finis isoparamétriques on utilise des objets tensoriels intrinsèques qui sont ramenés a une configuration de référence aplatie. Cette configuration aplatie est identifiée à l'élément de référence. En dehors d'une loi de comportement hyper élastique on présente deux lois élastoplastiques en grandes transformations supposant que les déformations locales restent petites. Les efforts résultants sont obtenus ou par une intégration numérique dans l'épaisseur ou a partir d'une loi de comportement globale qui est directement formulée en efforts résultants. L’implémentation numérique est effectuée dans un environnement de programmation orientée objet qui a été développe pour l'analyse non-linéaire par la méthode des éléments finis. En particulier, on regarde le rôle des grandes rotations dans le calcul de la matrice de rigidité tangente. Des résultats numériques confirment l'efficacité de cette approche.
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Boujelben, Abir. "Géante éolienne offshore (GEOF) : analyse dynamique des pales flexibles en grandes transformations." Thesis, Compiègne, 2018. http://www.theses.fr/2018COMP2442.
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L’objectif de ce travail porte sur le développement d’un modèle d’interaction fluide-structure adapté à la dynamique des éoliennes de grandes tailles avec des pales flexibles qui se déforment de manière significative sous l’effet de la pression exercée par le vent. Le modèle développé est basé sur une approche efficace d’IFS partitionnée pour un fluide incompressible et non visqueux en interaction avec une structure flexible soumise a des grandes transformations. Il permet de fournir une meilleure estimation de la charge aérodynamique et de la réponse dynamique associée du système (pales, mat, attachements, câbles) avec un temps de calcul raisonnable et pour des simulations sur des longues périodes. Pour la modélisation structurale, un élément fini de type solide 3D est développé pour l’étude dynamique des pales d’éolienne soumises à des grands déplacements et des grandes rotations. Une amélioration du comportement en flexion est proposée par l’introduction des degrés de liberté en rotation et l’enrichissement du champ de déplacements afin de décrire plus précisément la flexibilité des pales. Cet élément solide est apte de capter des modes de hautes fréquences qui peuvent s’avérer néfastes pour la stabilité du calcul. Deux techniques sont donc proposées pour les contrôler : la régularisation de la matrice masse et le développement des schémas d’intégration robustes de conservation et de dissipation d’énergie. Les chargements aérodynamiques sont modélisés en utilisant la Panel Method. Il s’agit d’une méthode aux frontières, relativement rapide par rapport à la CFD mais suffisamment précise pour calculer la distribution de la pression exercée sur la pale. Les modèles fluide et structure interagissent via un algorithme de couplage partitionné itératif dans lequel des considérations particulières sont prises en compte dans le contexte des grandes transformations. Dans un effort visant à instaurer un indicateur de fatigue dans la méthodologie proposée, des câbles précontraints sont introduits reliant le mat de l’éolienne au support. Une nouvelle formulation complémentaire en termes de contraintes est ainsi développée pour l’analyse dynamique des câbles 3D en comportement élasto-visco-plastique. Chaque méthode proposée a été d’abord validée sur des cas tests pertinents. Par la suite, des simulations numériques d’éoliennes avec des pales flexibles sont effectuées en vue d’affiner la compréhension de leur comportement dynamique et l’intérêt que la flexibilité des pales peut apporter à leur fonctionnementIn this work, a numerical model of fluid-structure interaction is developed for dynamic analysis of giant wind turbines with flexible blades that can deflect significantly under wind loading. The model is based on an efficient partitioned FSI approach for incompressible and inviscid flow interacting with a flexible structure undergoing large transformations. It seeks to provide the best estimate of true design aerodynamic load and the associated dynamic response of such system (blades, tower, attachments, cables). To model the structure, we developed a 3D solid element to analyze geometrically nonlinear statics and dynamics of wind turbine blades undergoing large displacements and rotations. The 3D solid bending behavior is improved by introducing rotational degrees of freedom and enriching the approximation of displacement field in order to describe the flexibility of the blades more accurately. This solid iscapable of representing high frequencies modes which should be taken under control. Thus, we proposed a regularized form of the mass matrix and robust time-stepping schemes based on energy conservation and dissipation. Aerodynamic loads are modeled by using the 3D Vortex Panel Method. Such boundary method is relatively fast to calculate pressure distribution compared to CFD and provides enough precision. The aerodynamic and structural parts interact with each other via a partitioned coupling scheme with iterative procedure where special considerations are taken into account for large overall motion. In an effort to introduce a fatigue indicator within the proposed framework, pre-stressed cables are added to the wind turbine, connecting the tower to the support and providing more stability. Therefore, a novel complementary force-based finite element formulation is constructed for dynamic analysis of elasto-viscoplastic cables. Each of theproposed methods is first validated with differents estexamples.Then,several numerical simulations of full-scale wind turbines are performed in order to better understand its dynamic behavior and to eventually optimize its operation
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Huang, He. "Experimental study of NiTi alloy under shear loading over a large range of strain rates." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066072.
Full textAbstract:
Ce travail décrit une étude expérimentale sur des tôles en Ni-Ti à température ambiante en cisaillement plan simple, et pour des vitesses de déformation de 10-4 à 103/s. En quasi-statique (10-4-10-2/s), la mesure optique du champ de déplacement est indispensable à cause du faible déplacement (0.3mm). Des essais à vitesse de déformation intermédiaire (10-1-101/s) ont été réalisés avec la Machine MTS modifiée, capable d'aller à 300mm/s. Une caméra rapide est nécessaire pour suivre ces tests. Enfin, des barres de Hopkinson sont utilisées pour les essais à haute vitesse (102-103/s).Les efforts se sont concentrés sur la méthodologie afin d'explorer les limites expérimentales. Au niveau mécanique, des efforts ont été apportés sur la conception des montages des mors pour combiner des exigences contradictoires. Au niveau mesure, des caméras optiques fonctionnant jusqu'à 5M images/s ont été utilisées. La texture des images, la peinture, la lumière, la taille d'élément et l'incertitude sont analysées. De plus, la caméra infrarouge est utilisée pour confirmer l'observation optique sous faibles vitesses de déformation.Finalement, des essais ont été réalisés pour 7 ordres de grandeurs de la vitesse de déformation, avec identification de la relation contrainte-déformation et observation de l'évolution de la bande de transformation. On observe : (i) Une augmentation de la contrainte avec la vitesse de déformation. (ii) Un champ de déformation non homogène, même en faible vitesse, avec une bande à 10 degrés par rapport à la direction de cisaillement. (iii) Deux bandes séparées à haute vitesse (102/s), ce qui indique que la bande de localisation dépend de la vitesse de chargementThis work describes an experimental study on a NiTi alloy at the ambient temperature (Pseudoelastic behavior) under the double in-plane shear loading over strain rates from 10-4 to 103/s. Under quasi-static loadings (10-4-10-2/s), the optical full-field measurement is necessary because of the very small displacement (0.3mm). The intermediate loading rates (10-1-101/s) are realized with a modified MTS machine able to load at 300mm/s. Moreover, a high-speed camera is needed to follow such tests. Finally, the Split Hopkinson bars are used to perform tests at impact loading rates (102-103/s).The main effort has been made on the methodological study to explore the experimental possibility. For the mechanical level, the attention has been paid on the design of the clamping system to cope with the contradictory requirements. For the measuring level, different optical cameras with sampling rate till to 5M frames/second are used. The texture, the painting, the lightening, the element size and the uncertainty are analyzed. Furthermore, an infrared camera was used at lower loading rates to confirm the DIC measurement.The tests are continually performed over 7 decades of the strain rate. The nominal stress-strain curves and the detailed observation of the transformation band evolution are measured. The main findings are as follows: (i) Regular stress increase with the strain rate; (ii) an inhomogeneous strain field under in-plane shear condition, even at very low strain rates, with a band at 10 degrees from the shear direction under lower strain rates. (iii) Two separated bands at the strain rate of 102/s, which suggests that the localized transformation bands are rate dependent
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Sahnine, Chawki. "Architecture de circuit intégré reconfigurable, très haut débit et basse consommation pour le traitement numérique de l'OFDM avancé." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0008.
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Cette thèse a pour but d'étudier les architectures de circuits intégrés pour le traitement numérique de l'OFDM avancé, très haut débit et multi-standard. Ces architectures visent à développer à la fois des puissances de calculs plus élevées pour répondre aux exigences de débit, ainsi que des capacités de reconfiguration pour des applications multi-standard. Elles doivent aussi respecter une contrainte de consommation réduite du fait de l'environnement embarqué des terminaux mobiles. En termes de solutions avancées, nous considérons deux schémas différents de la modulation OFDM, l'OFDM/QAM et l'OFDM/OQAM. Nous proposons une architecture à base de mémoires utilisant un multiplexage temporel des opérations sur une matrice de calcul à gros grain optimisée pour le traitement de la transformée de Fourier rapide et le filtrage polyphase. Nous proposons aussi une stratégie pour la gestion des mémoiresMost current wireless LANs and future Beyond 3G and 4G mobile networks involve the multicarrier OFDM transmission, based itself on the digital processing of the fast Fourier transform. These systems should cover bandwidths in the order of several tens or even hundreds of MHz. The aim of this thesis was to study the architectures of integrated circuit for a high speed and multi-standard OFDM digital processing. These architectures require both higher speed processing to meet the required throughput, and reconfiguration for multi-standard applications. Moreover, these architectures should meet the requirement of reduced power consumption due to the embedded environment of mobile terminals. In terms of advanced solutions, one considers two different OFDM modulation patterns, the OFDM/ QAM and OFDM/OQAM. This latter requires a pulse shaping polyphase filter implemented in our study on the IOTA prototype function. One considers also SISO/MIMO functionalities. A comparative analysis of various FFT algorithms and architectures has led to identify the best approach which gives a good algorithm architecture adequation. This solution also incorporates the pulse shaping filter, more precisely implementing the IOTA function. One has therefore proposed a memory-based architecture using a time multiplexed operations on a coarse grained matrix optimized for the treatment of the FFT and of the pulse shaping filtering. This time approach allows a realization of advanced OFDM modulation for values of the parameter N, the number of subcarrier, from 64 to 8192 and the parameter L, the truncation length for pulse shaping filter, equal to 2, 4 and 8. The architecture of the matrix applies the same treatment on two or four streams of different samples, for modes MIMO 2x2 and 4x4 respectively. A strategy to manage memories has also been proposed. It is based on a memory banks approach to obtain various memory sizes and to enable the turn of the unnecessary memories. A first FPGA prototyping and an ASIC layout design have validated the functioning and the feasibility of the architecture. The FPGA prototyping platform used was the ML402 from Xilinx incorporating the FPGA XC4VSX35 from the Virtex-4 family. The ASIC layout design has been done using the submicronic 65 nm CMOS technology from STMicroelectronics. The performances obtained out of this architecture makes it a good candidate to cover the different standards based on OFDM modulation
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Gaharia, David. "Asymptotic Symmetries and Faddeev-Kulish states in QED and Gravity." Thesis, Stockholms universitet, Fysikum, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-166311.
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When calculating scattering amplitudes in gauge and gravitational theories one encounters infrared (IR) divergences associated with massless fields. These are known to be artifacts of constructing a quantum field theory starting with free fields, and the assumption that in the asymptotic limit (i.e. well before and after a scattering event) the incoming and outgoing states are non-interacting. In 1937, Bloch and Nordsieck provided a technical procedure eliminating the IR divergences in the cross-sections. However, this did not address the source of the problem: A detailed analysis reveals that, in quantum electrodynamics (QED) and in perturbative quantum gravity (PQG), the interactions cannot be ignored even in the asymptotic limit. This is due to the infinite range of the massless force-carrying bosons. By taking these asymptotic interactions into account, one can find a picture changing operator that transforms the free Fock states into asymptotically interacting Faddeev- Kulish (FK) states. These FK states are charged (massive) particles surrounded by a “cloud” of soft photons (gravitons) and will render all scattering processes infrared finite already at an S-matrix level. Recently it has been found that the FK states are closely related to asymptotic symmetries. In the case of QED the FK states are eigenstates of the large gauge transformations – U(1) transformations with a non-vanishing transformation parameter at infinity. For PQG the FK states are eigenstates of the Bondi-Metzner-Sachs (BMS) transformations – the asymptotic symmetry group of an asymptotically flat spacetime. It also appears that the FK states are related the Wilson lines in the Mandelstam quantization scheme. This would allow one to obtain the physical FK states through geometrical or symmetry arguments. We attempt to clarify this relation and present a derivation of the FK states in PQG from the gravitational Wilson line in the eikonal approximation, a result that is novel to this thesis.
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Rasch, Linnéa, and Victor Thun. "The Road to Become Agile : A case study of agile transformations in the retail market, including an organization development approach." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279642.
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In today’s volatile market, retail companies struggle for survival as they have to become more flexible and dynamic. Thus, they change the organization, implementing agile methods. However agile is more than a set of practices and therefore the implementation process needs to be accompanied by organizational development to accomplish successful organizational change. This has been shown to be difficult for retail companies due to their size, defined silos, comfortable long-established ways of doing things and strong bureaucratic hierarchical culture. This thesis studies the implementation of agile in a large-scale retail organization and uses organizational development as a tool for deeper understanding and analysis. The study has been conducted at one of Sweden's leading retail organizations, where the research design contains two phases: one pre-study phase where a deeper understanding of the company and the transformation is achieved resulting in a problem formulation and the second phase where the main study is directed by the problem formulation and leads to an analysis and conclusion. The analysis is based on empirics gathered from three separate teams and is divided into three interconnected change phases, “Preparation”, “Implementation” and “Desired state”. From the analysis in the preparation and implementation phases; strengths and challenges within the organization were identified. Together with a maturity model to evaluate the implemented agile practices and an organizational culture assessment instrument to evaluate people and culture, the strengths and challenges were then used to estimate their current state and compare it to their future desired state. In conclusion, the strengths of the case company were that, when implemented, the observed teams incorporated the agile ceremonies and ways of work successfully. However, there were challenges identified in relation to resistance within management, there was a general lack of support from the sponsors and confusion about the managerial roles. There was also a lack of communication, cooperation and synchronizations between teams.I dagens flyktiga marknader kämpar företag inom dagligvaruhandeln för att överleva då de måste bli mer flexibla och dynamiska i deras strategi. För att bemöta detta ändrar företagen sin strategi genom implementering av agila metoder. Emellertid handlar att vara agil inte bara om att använda sig av olika verktyg och övningar för att ändra hur man arbetar, utan för att implementeringen av agila metoder ska vara lyckad, måste den följas med av en lyckad organisationsförändring. En sådan agil implementering och organisationsförändring har visats vara komplicerad i just dagligvaruhandeln på grund av organisationernas ofta stora storlek, definierade silos, komfortabla gamla traditioner och starka hierarkiska organisationskultur. Denna uppsats studerar implementationen av agilt i ett storskaligt företag inom dagligvaruhandeln och använder sig av organisationsutveckling som ett verktyg för att nå en djupare förståelse och analys. Analysen är uppdelad i tre olika sammanhängande faser “Förberedelse”, “Implementering”, och “Önskat Tillstånd”. Empirin analysen är baserad på kommer från tre olika separata team, vilka är i olika faser av den agila transformationen. I förberedelse- och implementeringsfaserna identifieras styrkor och utmaningar hos företaget. Dessa används sedan tillsammans med en mognadhetsmodell, för att evaluera de agila tillvägagångssätten samt ett bedömningsinstrument för organisationskultur, för att evaluera personer och kultur, i syfte att sedan utvärdera det nuvarande tillståndet i jämförelse med det önskade. Sammanfattningsvis lyckades de observerade teamen att framgångsrikt implementera de agila metoderna och arbetssätten. Däremot identifierades flera utmaningar i relation till motstånd inom management. Det fanns en generell förvirring kring chefs rollernas betydelse och det saknades stöd från ledningsgruppen. Slutligen identifierades även förbättringsområden inom kommunikation, samarbete och synkronisering mellan olika team.
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Hagg, Heather. "Large System Transformation within Healthcare Organizations utilizing Lean Deployment Strategies." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-dissertations/415.
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"Multiple U.S. healthcare organizations have been recognized as successful in enterprise-level transformation to create healthcare delivery systems that are safe, effective, patient-centered, timely, efficient and equitable. Many of these organizations have specifically cited the development, deployment and integration of enterprise-level deployment of Lean Management Systems as key to their transformational efforts. Given the intense national interest in improving quality, efficiency and efficacy of healthcare delivery systems, a greater understanding of the strategies utilized by these organizations was required in order to provide an understanding of the mechanisms that drive successful, sustained, enterprise-level transformation. We conducted a realist review of large system transformation utilizing enterprise-level Lean Deployment methods within healthcare organizations. Synthesis and analysis of the results from this review indicate that there are five primary strategies associated with successful healthcare-based Lean deployments: Respect for People; Strategic Alignment; Strategic Deployment; Large Scale System Improvement Efforts; and Small-Scale, Local Improvement Efforts. Additional findings from this review indicate that the applications of the specific mechanisms with these strategies are emergent within multiple transitional phases spanning 6-8 years. To supplement the findings from the realist review, a series of dynamic hypotheses and system dynamics model was created in order to explore how the mechanisms and context interact to drive phase transitions within healthcare-based enterprise-level Lean deployments. The results from this model indicate that no steady state initial conditions exist that support sustained enterprise-level transformation and that the emergent nature of these deployments is necessary to overcome constraints related to the organizational capacity and capability. Additionally, we investigate the design and deployment of enterprise-level Lean programs in order to increase rate of success and decrease deployment cycles. "
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Giese, Holger, and Stephan Hildebrandt. "Efficient model synchronization of large-scale models." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/2928/.
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Model-driven software development requires techniques to consistently propagate modifications between different related models to realize its full potential. For large-scale models, efficiency is essential in this respect. In this paper, we present an improved model synchronization algorithm based on triple graph grammars that is highly efficient and, therefore, can also synchronize large-scale models sufficiently fast. We can show, that the overall algorithm has optimal complexity if it is dominating the rule matching and further present extensive measurements that show the efficiency of the presented model transformation and synchronization technique.Die Model-getriebene Softwareentwicklung benötigt Techniken zur Übertragung von Änderungen zwischen verschiedenen zusammenhängenden Modellen, um vollständig nutzbar zu sein. Bei großen Modellen spielt hier die Effizienz eine entscheidende Rolle. In diesem Bericht stellen wir einen verbesserten Modellsynchronisationsalgorithmus vor, der auf Tripel-Graph-Grammatiken basiert. Dieser arbeitet sehr effizient und kann auch sehr große Modelle schnell synchronisieren. Wir können zeigen, dass der Gesamtalgortihmus eine optimale Komplexität aufweist, sofern er die Ausführung dominiert. Die Effizient des Algorithmus' wird durch einige Benchmarkergebnisse belegt.
29
Berglund, Mattias. "Molecular Characterization of Diffuse Large B-cell Lymphoma and Aspects of Transformation." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4266.
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FANGAZIO, MARCO. "Molecular Determinants of Follicular Lymphoma Transformation to Diffuse Large B cell Lymphoma." Doctoral thesis, Università del Piemonte Orientale, 2014. http://hdl.handle.net/11579/46568.
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Ovarlez, Jean-Philippe. "La transformation de mellin : un outil pour l'analyse des signaux a large bande." Paris 6, 1992. http://www.theses.fr/1992PA066282.
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Un grand nombre de methodes actuelles d'analyse de signaux n'ont de justification theorique acceptable que pour la categorie bien particuliere des signaux a bande etroite, associee au groupe des translations en temps et en frequence. C'est le cas des representations temps-frequence de la classe de cohen, mais aussi, des fonctions d'ambiguite generalisees. Ces formes sont etroitement liees au mode de transformation du groupe affine qui agit sur les signaux par translation et compression de temps. Elles sont, de ce fait, beaucoup plus difficiles a utiliser et a calculer numeriquement. La transformation de mellin s'est alors, par sa puissance et sa simplicite d'emploi, revelee etre un outil particulierement adapte pour resoudre des problemes theoriques mais aussi algorithmiques associes a ces effets de compression. On propose, dans cette these, de decouvrir cette nouvelle transformation qui possede de nombreuses analogies avec celle de fourier (interpretation physique de la variable de mellin, proprietes, forme discretisee, theoreme d'echantillonnage). Toutes les nouvelles applications, resultats theoriques ou algorithmes rapides qui en decoulent, sont presentes: le calcul des distributions temps-frequence affines et leurs regularisees (transformation en ondelette) ainsi que les fonctions d'ambiguite generalisees, l'elaboration des bornes de cramer rao pour les estimateurs retard-vitesse dans le cas d'un radar large bande, et finalement, une application operationnelle, l'imagerie radar multidimensionnelle par transformation en ondelette dimensionnees
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Williamson, Phillip C. "A Novel Mechanism for Site-Directed Mutagenesis of Large Catabolic Plasmids Using Natural Transformation." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2828/.
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Natural transformation is the process by which cells take up DNA from the surrounding medium under physiological conditions, altering the genotype in a heritable fashion. This occurs without chemical or physical treatment of the cells. Certain Acinetobacter strains exhibit a strong tendency to incorporate homologous DNA into their chromosomes by natural transformation. Transformation in Acinetobacter exhibits several unique properties that indicate this system's superiority as a model for transformation studies or studies which benefit from the use of transformation as an experimental method of gene manipulation. Pseudomonas putida is the natural host of TOL plasmids, ranging between 50 kbp and 300 kbp in size and encoding genes for the catabolism of toluene, meta-toluate, and xylene. These very large, single-copy plasmids are difficult to isolate, manipulate, or modify in vitro. In this study, the TOL plasmid pDKR1 was introduced into Acinetobacter calcoaceticus strains and genetically engineered utilizing natural transformation as part of the process. Following engineering by transformation, the recombinant DNA molecule was returned to the native genetic background of the original host P. putida strain. Specific parameters for the successful manipulation of large plasmids by natural transformation in Acinetobacter were identified and are outlined. The effects of growth phase, total transforming DNA concentration, transforming DNA conformation, and gene dosage on transformation efficiency are presented. Addition of Acinetobacter plasmid DNA sequences to the manipulated constructs did not have an effect on transformation rates. Results suggest that a broadly applicable and efficient method to carry out site-directed genetic manipulations of large plasmids has been identified. The ability to easily reintroduce the recombinant DNA molecules back into the original host organism was maintained.
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MUHAMMED, MONIR. "The importance of addressing culture in large transformational change programs in public organisations." Thesis, KTH, Tillämpad maskinteknik (KTH Södertälje), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170092.
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Hodzic, Adis. "The transformation to digital : How industry 4.0 affects the digital transformation – a study of industry 4.0 and how it affects the digital transformation at a large Swedish manufacturing company." Thesis, Linnéuniversitetet, Institutionen för informatik (IK), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105720.
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The fourth industrial revolution is the latest revolution that has emerged within the industrial sector. The concept has become more known in recent years and with the different technologies it brings to the companies, it creates a race around the world for companies in order to be among the first to implement the new technologies. With the growing interest in industry 4.0 and the implementation of the new technologies, it has created a need to rethink on how to be successful in this transformation. To be successful in implementing industry 4.0 it is important to involve all the different aspects of a company’s supply chain. This qualitative study aims to investigate how industry 4.0 affects the digital transformation at a large manufacturing company in Sweden. The thesis includes five different technologies within industry 4.0: Internet of things, the cloud, simulations, autonomous robots and big data and analytics. The five technologies are then investigated on how they affect the digital transformation of the chosen company. The results of the findings shows that industry 4.0 has an affect on the digital transformation of the company after it was implemented. However, the results also shows that some technologies have had a greater impact to the digital transformation then others, but there isn´t one technology that has not affected the transformation at all. Additionally, the results shows that the part of digital transformation that is affected the most from industry 4.0 is the changes it creates in the value creation of the company. This thesis aims to create a better understanding about industry 4.0 and how it affects the digital transformation of a large manufacturing company.
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Oliver, Wendy. "The impact of leadership styles on employee engagement in a large retail organisation in the Western Cape." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/5067.
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Magister Commercii (Industrial Psychology) - MCom(IPS)To gain further insight, the purpose of this study was to investigate the impact of leadership styles, particularly the impact of transformational and transactional leadership on employee engagement. Within a business context, transformational leaders are those “extraordinary” individuals that have the ability to capture their employees’ attention, intellectually stimulate them and strategically align them with the vision and mission of the organisation. Contrary to this, is transactional leadership which is basically an exchange relationship between the leader and employee whereby the leader exchanges rewards and/or incentives for performance. Both styles of leadership are instrumental in engaging employees within the organisation, although a plethora of literature suggests that transformational leadership impacts more significantly on employee engagement (Schaufeli & Bakker, 2004).
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Kumar, Abhimanyu. "Comprehensive Modeling of Shape Memory Alloys for Actuation of Large-Scale Structures." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1289883464.
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Bigrigg, Margaret Alison. "The use of large loop excision of the transformation zone for the treatment of cervical intraepithelial neoplasia." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238899.
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Ostreus, Amelie, and Jenny Brandt. "Agile project management: Scrum in large project - how is the internal communication affected?" Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20153.
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Idag använder de flesta mjukvaruföretag agil utveckling och en av de vanligaste agila metoderna är Scrum. Under de senaste åren har det blivit vanligt att använda Scrum i större projekt trots dess anpassning för mindre projekt. Följaktligen har olika ramverk utvecklats för att skala Scrum till mer än ett team och för att stödja metoden i större projekt. Det finns flera kommunikativa utmaningar i denna transformationen som har resulterat i en förändring i det smidiga arbetet som påverkar teamets sätt att kommunicera och samverka. Detta ställer nya krav på samarbete och samordningen mellan de olika team som arbetar med samma projekt. I denna studie har målet varit att med hjälp av en kvalitativ ansats undersöka hur kommunikationen påverkas av det faktum att något som ursprungligen var anpassat för mindre projekt, nu ska användas för stora projekt där många parter är involverade och beroende av varandras arbete. Slutsatserna har dragit utifrån kombinationen av en teoretisk referensram och sex intervjuer med Scrum masters och teammedlemmar. Studien visar på att en stor kommunikativ utmaning är att ha en fortlöpande kommunikation mellan teamen och att uppnå en samverkan trots den distanseringen som följer vid skalning. Strategier för hur skalningen av Scrum ska ske på bästa sätt skiljer sig åt, men det finns en enighet om att strukturer, ett gemensamt “språk” och vision krävs för att samarbetet mellan teamen skall fungera effektivt och för att den interna kommunikationen ska bli lyckad.Today, most software companies use agile development and one of the most common agile methods is Scrum. In recent years, it has become common to use Scrum in larger projects despite its adaptation for smaller projects. Consequently, different frameworks have been developed for scaling Scrum to more than one team and to support the method in larger projects. There are several communicative challenges to this transformation and the transformation has resulted in a change in the agile work that affects the team's way of communicating and interacting. Which puts new demands on collaboration and coordination between the different teams working on the same project. The aim in this study has been to investigate how communication is affected by the fact that something that was originally adapted for smaller projects should now be used for large projects where many different parties are involved and dependent on each other´s work using a qualitative approach. The conclusions have been based on the combination of a theoretical framework and six interviews with Scrum Masters and team members. The study shows that a major communicative challenge is to have continuous communication between the teams and to achieve a collaboration despite the distancing that comes with scaling. Strategies for how to scale Scrum separates, but there is a consensus that structures, a common “language” and vision are required for an effective collaboration between the teams and for internal communication to be successful.
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Strüber, Daniel [Verfasser], and Taentzer [Akademischer Betreuer]. "Model-Driven Engineering in the Large: Refactoring Techniques for Models and Model Transformation Systems / Daniel Strüber. Betreuer: Taentzer." Marburg : Philipps-Universität Marburg, 2016. http://d-nb.info/1089078064/34.
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Gumus, Ayse Nazli. "Becoming A Neo-liberal City: Ankara North Entrance Urban Transformation Project." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611956/index.pdf.
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Urban space has begun to be commodified to full extent by the affect of neoliberalism, which is bared upon free flow of capital over a global network of cities. By 1970&rsquos, the phenomenon of globalization made social, political and economic relations all around the world to be redefined under these circumstances. While nation states were altering their role in favor of capital power, early centers of production have come to lose their attractiveness and functions, and in especially developed countries there emerged necessity for the notion of &ldquo
urban transformation&rdquo
. On the other hand, in Turkey, urban transformation projects have begun to be applied lately, under specific conditions and with different reasons, but still under neo-liberal hegemony. The aim of this thesis is to make a comparative analysis of &ldquo
Ankara North Entrance Urban Transformation Project&rdquo
by understanding the notion of urban transformation together with altered role of nation state at the age of neoliberalism, by comparatively analyzing grand transformation projects applied at three capital cities in Europe, namely, London, Paris, and Berlin, during late 20th century. The comparison criteria for project preparation and application processes of the case of Ankara and European examples are, first, the scale and location within the city
second, reasons of application in terms of their legitimating processes
third, the ways of providing financial resources for projects
fourth, administrative dimension of urban policy making
fifth, architectural domain of the projects
and lastly participation conditions of urban inhabitants and social agents, including the professionals.
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Hägg, Jesper, and Sandy Sandhu. "Do or Die: How large organizations can reach a higher level of digital maturity." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64137.
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The business landscape as we know it is being disrupted by an increasing usage of emerging digital technologies, to reap the benefits of the new technological opportunities managers need to transform their organizations. To do so, research literature proposes striving towards digital maturity. However, knowledge within the area of digital transformation and digital maturity is insufficient amongst organizational leaders. Moreover, theoretical guidance in terms of which changes that are required to increase digital maturity in an organization, is still absent in research literature. To address the academic gap and provide guidance in practical challenges, the research objective to create a framework to evaluate digital maturity was constructed. To reach this objective, the following research questions were derived: RQ1: Which levels can digital maturity be divided into and what characterizes each level? RQ2: When progressing upwards along the digital maturity scale, what are the key dimensions that allow transition from one level to the next? To answer the research questions and thereby meet the research objective, an abductive, multiple case study of large companies in the manufacturing and service industry was performed. 16 interviews and two workshops were conducted to provide the data which was then thematically analyzed and structured to provide answers to the research questions. Our findings were then used to construct the Digital Maturity Framework. Our findings suggest the following three levels of digital maturity; Awareness, Experience, and Autonomy. The characteristics of each levels is expressed in six organizational dimensions, namely Processes, Leadership, Culture, Strategy, Analytics, and IT. To transit from one maturity level to the next, Leadership in terms of change management is a key dimension in all transitions. Before organizations qualify for the level Awareness, they must first lay the foundation through Process management. Experimenting and testing new digital tools and technologies is a key dimension to reach the level Experience, and Strategy is a key dimension in both the transition to Experience and the transition to Autonomy. Our findings contribute with a more nuanced framework of digital maturity as well as guidance for managers about what they need to do to progress in digital maturity. The importance of change management is the most valuable managerial implication of our findings, because change will always trigger friction in the organization, which in turn requires strong and driven leaders to drive the change.
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Mohammed, Ismael, and Foma Awambeng Kenne. "Digital Transformation in the Logistics Industry : An investigative analysis comparing the impact of digital transformation and consumer behavior on the business models of small & large logistics organizations." Thesis, Högskolan i Jönköping, Internationella Handelshögskolan, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-39880.
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Digital Transformation is an on-going process in the logistics industry. Every day, innovative and new technology is developed to streamline products to the customer as fast as they want it. The purpose of our study is to investigate how digital transformation and customer behaviour has affected the business model(s) of smaller companies compared to well established multinational companies in the logistics industry. The authors look and found the aspects of the business model that were impacted and if there should be adjustments made to better suite either the large or small organizations.
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Erhart, Kevin. "A Laplace Transform Boundary Element Method Approach to the Solution of Large-Scale Transient Heat Conduction Problems." Honors in the Major Thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/705.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Engineering and Computer Science
Mechanical Engineering
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Beese, Allison M. "Experimental investigation and constitutive modeling of the large deformation behavior of anisotropic steel sheets undergoing strain-induced phase transformation." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67576.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 139-146).
The strain-induced phase transformation from austenite to martensite is responsible for the high strength and ductility of TRansformation-Induced Plasticity (TRIP)- assisted steels. The large deformation behavior of conventional steels is governed by crystallographic slip. In the case of TRIP steels, the phase transformation provides an additional microstructural deformation mechanism, which has a particularly strong effect on the strain hardening response at the macroscopic level. This thesis work develops a new plasticity model for TRIP steels that accounts for the effect of phase transformation. In particular, the large deformation behavior of 1.5mm thick stainless steel 301LN sheets at room temperature is studied in detail. Several techniques for quantifying the martensite volume fraction are evaluated including micrography, X-ray diffraction, neutron diffraction, magnetic saturation, and magnetic permeability measurements. The latter is then used to measure the evolution of the martensite content throughout mechanical experiments. The experimental program for different stress states includes experiments for uniaxial tension, uniaxial compression, equi-biaxial tension, pure shear, and transverse plane strain tension. The resulting experimental data demonstrate the influence of both the stress triaxiality and Lode angle parameter on the austenite-to-martensite transformation kinetics. A stress-state dependent transformation kinetics evolution equation is proposed which describes the martensite content as a function of plastic strain, the stress triaxiality, and the Lode angle parameter. Furthermore, a phenomenological plasticity model is developed comprising an anisotropic yield function, an isotropic hardening law, and a nonlinear kinematic hardening law with initial back stress. The isotropic hardening law expresses the increase in deformation resistances as a function of the plastic strain and the martensite content and is directly coupled with the stress-state dependent transformation kinetics equation. As a result, the model is able to describe the experimentally observed effect of stress state on the macroscopic hardening response. The constitutive model is implemented into a finite element program and used to simulate all experiments performed. The model predictions agree well with the experimental results for a wide range of stress states and for both specimens with homogeneous and heterogeneous stress and strain fields.
by Allison M. Beese.
Ph.D.
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Lissitsa, Alexej. "Der Transformationsprozess in der Landwirtschaft der Ukraine eine Analyse der Effizienz und Produktivität von Grossbetrieben /." Aachen : Shaker, 2002. http://catalog.hathitrust.org/api/volumes/oclc/52270904.html.
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Larousse, Paul. "Modélisation d'interface endommageable en dynamique explicite dédiée au démoulage de pneumatiques." Electronic Thesis or Diss., Lyon, INSA, 2024. http://www.theses.fr/2024ISAL0098.
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Le pneumatique est un produit complexe soumis à de nombreuses contraintes. Il doit répondre à un compromis entre coût, performance, sécurité et recyclabilité. Il est formé d'une multitude de couches composées de différents matériaux entraînant des comportements complexes à étudier. Ainsi, le choix de la simulation numérique s’impose, permettant notamment l’étude de nombreux scénarios. Elle permet d'étudier l'impact de chaque étape de fabrication, et notamment celle du démoulage, qui a inspiré cette thèse. Ce problème non-régulier est associé à du contact et de l'endommagement, modélisés à l’aide de modèle de zones cohésives, et à de la dynamique rapide, phénomènes rarement combinés ensemble en simulation. Le problème à résoudre étant en dynamique transitoire, le choix d’un intégrateur temporel explicite s’impose. L'idée ici est d'utiliser un schéma explicite symplectique possédant ainsi de bonnes propriétés énergétiques en vérifiant les équations de conservation discrètes. Basé sur des travaux antérieurs, le choix est porté sur le schéma explicite CD-Lagrange. Ainsi, l'étude se concentre sur l'interface de contact entre un solide déformable, et un solide rigide. Une méthode pour résoudre en dynamique des problèmes d’interface est présentée. Un cadre thermodynamique et explicite de résolution est alors proposé, avec un traitement local des non-linéarités et des non-régularités conduisant à un algorithme de résolution "matrix-free". Les formulations sont basées sur le cadre thermodynamique des matériaux standards généralisés et de la mécanique non régulière. Ensuite, l'accent est mis sur les lois d'évolution thermodynamique en étudiant la non-localité temporelle pour limiter la localisation de l’endommagement sur l’interface. Des modèles à effet retard sont alors introduits. L'aspect modulaire de la résolution proposée est montré, avec l’application de plusieurs lois d’interface et de comportement volumique. L'application à des problèmes en grandes transformations est également fournie. Enfin, la faisabilité de l'approche est mise en évidence par son intégration dans un code semi-industriel, MEF++The tire is a complex product subjected to numerous constraints, and the designer must find a compromise between cost, performance, safety and recyclability. It is composed of a multitude of overlayed layers of different materials, resulting in complex behaviors. Thus, numerical simulation is an obvious choice by allowing the study of a wide range of scenarios. It enables to study the impact of each manufacturing step, and in particular the unmolding tire process, which inspired this thesis. This non-regular problem is associated to contact and damage, described by a cohesive zone model, with fast dynamics phenomena, rarely combined together in simulation. Since the problem is a transient dynamics one, the choice of an explicit time integrator is natural. The proposed idea here is the use of an explicit symplectic scheme providing by definition good energy properties and discrete equations conservation. Based on previous work, the explicit CD-Lagrange scheme is chosen. Thus, the study is focused on the contact interface between a deformable solid and a rigid one. A method for solving interface problems in dynamics is presented. A thermodynamic and explicit resolution framework is then proposed, with local treatment of non-linearities and non-regularities leading to a matrix-free resolution algorithm. Formulations are based on the thermodynamic framework of generalized standard materials and non-regular mechanics. Next, the focus is set on the thermodynamic evolution laws by studying temporal non-locality in order to limit the damage localization on the interface. Delayed-effect models are then introduced. The modular aspect of the proposed resolution is shown, with application of several interface laws and bulk behaviors. Application to large transformation contact problems is also provided. Finally, the feasibility of the approach is demonstrated by its integration into a semi-industrial code, MEF++
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Timur, Emre Robert, and Byggnings Lina Lindbom. "Managing transformation pressure in large organizations : A case study on a product development organization in the transport and truck industry." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264097.
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Why do some large organizations succeed during transformations and others do not? This thesis aims to contribute and expand the discussion of how product development capabilities could enable success during transformations. To investigate the problem, a qualitative case study was performed at a large transport and truck incumbent, Scania CV AB. The transport and truck industry is currently pressured to transform, both from a competitive and sustainability perspective. In order to become more adaptable to change, the thesis identified the importance of clearly applying ambidexterity as a strategy to cope with challenges that the transformation implies. However, when applying ambidexterity, interface challenges between exploitation and exploration occur. Success during transformations is mainly dependent on the management to handle those interface challenges properly. This thesis identified two main managerial practices that could benefit incumbents in the transport and truck industry to become more adaptable during a transformation phase. Firstly, a clear strategy of how to manage innovations over time could support large incumbents to leverage innovations for optimal experimentation, scalability, and later profit. Secondly, clear organizational alignment between functions to enhance communication and prioritization especially between exploitative and explorative business activities could support large incumbents to leverage radical innovations within the organization. This thesis argues that implementing structural ambidexterity combined with a clear and streamlined innovation transfer process in three distinct horizons for mature, growth, and future businesses will increase adaptability during transformation pressure. As the main area of future research, this thesis proposes to further investigate the opportunities of an open innovation strategy that leverages partnerships for co-creation in an increasingly interconnected transport ecosystem.Hur kommer det sig att vissa företag lyckas under industriell förändring och andra inte? Syftet med denna uppsats är att bidra till, och utvidga, diskussionen om hur kapabiliteter inom produktutveckling kan främja en lyckad transformation. För att undersöka problemet genomfördes en kvalitativ fallstudie på ett etablerat företag inom transport och lastbilsindustrin, Scania CV AB. Transportindustrin är för närvarande under stor press, både från ett konkurrens- och hållbarhetsperspektiv. Denna studie visar att, för att bli mer adaptiv och hantera förändring, är det av yttersta vikt att implementera en tydlig strategi för en tvehänt (ambidextrous) organisation. En av de största utmaningarna vid en sådan implementation är dock de starka spänningar som uppstår i gränssnitten mellan det operationella och det utforskande inom organisationen. Hur de hanterar dessa utmaningar från ett ledarskapsperspektiv, kommer därav vara en av de främsta faktorerna till om företaget lyckas anpassa sig till förändring. I studien har två grundläggande principer för ledarskap identifierats, vilka kan hjälpa etablerade företag inom transport- och lastbilsindustrin att bli mer adaptiva under förändring. För det första, en tydlig strategi för att hantera innovation över tid, kan stötta ett etablerat företag att optimera innovation, skalbarhet och vinst. För det andra, en tydlig organisations- och ledarskapsinriktning som lyfter kommunikation och underlättar prioritering mellan förvaltande och utforskande aktiviteter och avdelningar. Denna studie argumenterar för strukturell separering av organisationen, kombinerat med en process för att överföra innovationer. Detta kan åstadkommas genom en uppdelning på tre horisonter; mognad, tillväxt och framtid, vilket kommer att öka företagets anpassningsförmåga under förändring. Denna studie har avgränsats till att inte närmare undersöka hur partnerskap kan hanteras i det allt mer sammankopplade transportsystemet. Detta är dock identifierat som ett möjligt behov av att närmare undersöka hur strategier för open innovation kan främja partnerskap och samproduktion inom området.
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BEDNARCIK, ABDULHADI EMMA, and MARINA VITEZ. "The Ownership Structure Dilemma and its Implications on the Transition from Small-Scale to Large-Scale Electric Road Systems." Thesis, KTH, Industriell Management, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191130.
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This master thesis is written on behalf of KTH Royal Institute of Technology and the Swedish National Road and Transport Research Institute (VTI). The study investigates how infrastructure ownership could affect the transition from small-scale to large-scale electric road systems (ERS) and how infrastructure ownership affects the foreseen future roles of the ERS stakeholders. The authors have used a qualitative research method, including a literature study within the areas of infrastructure transitions and infrastructure ownership and a case study on ERS. Conclusions are based on the chosen theoretical framework and the empirical findings from conducted interviews within the following stakeholder segments; agencies, electric utilities, road carriers, construction firms and road power technology firms. The transport system is a large sociotechnical system, which is characterized by a high level of complexity, capital intensity and asset durability which makes it difficult to accomplish radical system transitions. Political regulations and progressive environmental targets have created a demand for new solutions within the transport system. One widely discussed, possible solution is ERS, which are considered to be beneficial from both an environmental and socio-economic perspective. The main identified barriers for a transition to ERS are related to the complex system design. Further, the matter of how the ERS infrastructure should be owned and financed remains unclear. It will be argued that the government needs to play a key role, both as a coordinator and financier, during the initial phase of an ERS expansion. In order to obtain a high level of competence, which is considered as vital, it is important with close cooperation between different public and private stakeholders and to have a procurement process which is strongly focused on functionality. The authors suggest that in order to decrease system complexity and increase stakeholder cooperation, cross-sectorial system suppliers should be formed. During an initial deployment of ERS towards a national system, it is suggested to only have one cross-sectorial system supplier which manages the constructions and operations of ERS, in order to decrease complexity and increase knowledge. As the system and technology matures and knowledge regarding ERS has been established, it is suggested by the authors to introduce competition at the cross-sectorial system supplier level nationally. There are many barriers for public private partnerships (PPP) during an initial expansion phase of ERS due to large investments, immature technology and the necessity for an overall control of a large-scale system. In addition, early investments in a large-scale system is considered as unattractive among private actors due to the high risks. However, it will be argued that PPP structures or private ownerships are suitable in closed systems as the level of complexity is lower. These systems should be subsidized by the government as they will drive innovation and stimulate the development. Depending on the degree of capital intensity and governmental regulations, PPP structures could become suitable also in a national system, when the system has matured. The suggested stakeholder structure with cross-sectorial system suppliers facilitates for a possible future PPP structure.Denna masteruppsats är skriven på uppdrag av Kungliga Tekniska Högskolan och Statens väg- och transportforskningsinstitut (VTI). I studien undersöks hur ägarskap av infrastruktur skulle kunna påverka skiftet från småskaliga till storskaliga elvägssystem och hur ägarskapet av infrastrukturen påverkar de förutsedda framtida rollerna hos elvägssystemets intressenter. Författarna har använt sig av en kvalitativ forskningsmetod, vilken inkluderar en litteraturstudie inom områden för infrastrukturskiften och ägarskap av infrastruktur samt en fallstudie inom elvägssystem. Slutsatser är baserade på det valda teoretiska ramverket och de empiriska resultaten från de genomförda intervjuerna inom följande intressentsegment; myndigheter, energibolag, godstransportörer, konstruktionsfirmor och tillverkare av elvägsinfrastruktur. Transportsystemet är ett stort sociotekniskt system, vilket karakteriseras av en hög nivå av komplexitet, kapitalintensitet och lång livslängd på tillgångar, vilket gör det svårt att uppnå radikala systemskiften. Politiska regleringar och progressiva miljömål har skapat ett behov för nya lösningar inom transportsystemet. En diskuterad möjlig lösning är elvägssystem, vilket anses vara fördelaktigt både från ett miljömässigt och socioekonomiskt perspektiv. De huvudsakliga identifierade barriärerna för ett skifte till ett elvägssystem är relaterade till den komplexa systemdesignen. Vidare är frågan rörande hur infrastrukturen till ett elvägssystem ska ägas och finansieras fortfarande oklar. Det kommer att argumenteras för att staten behöver ha en nyckelroll, både som koordinator och finansiär, under den initiala expansionsfasen av ett elvägssystem. För att uppnå en hög nivå av kompetens, vilket anses vara avgörande, så är det viktigt med ett nära samarbete mellan olika statliga och privata intressenter och att ha en upphandlingsprocess som starkt fokuserar på funktionalitet. Författarna föreslår att för att minska systemets komplexitet och öka intressenternas samarbete, så borde tvärsektoriella systemleverantörer formas. Under en initial utbredning av elvägssystem mot ett nationellt system, så föreslås det att enbart ha en tvärsektoriell systemleverantör som sköter konstruktion och verksamhet av elvägssystemet för att minska komplexiteten och öka kunskapen. Allt eftersom att systemet och teknologin mognar och kunskap om elvägssystem etableras, så föreslår författarna att konkurrens ska introduceras på tvärsektoriell systemleverantörsnivå nationellt. Det finns många barriärer för offentlig-privat samverkan (OPS) under den initiala expansionsfasen av elvägssystem på grund av stora investeringar, omogen teknologi och behovet av övergripande kontroll i ett storskaligt system. Dessutom anses tidiga investeringar i ett storskaligt system vara oattraktivt hos de privata aktörerna på grund av de höga riskerna. Det kan dock argumenteras för att OPS-strukturer eller privat ägande är passande för slutna system då nivån av komplexitet är lägre. Dessa system borde subventioneras av staten då de kommer driva innovation och stimulera utvecklingen. Beroende på graden av kapitalintensitet och statliga regleringar, skulle OPS-strukturer också kunna vara lämpliga för ett nationellt system, när systemet har mognat. De föreslagna intressentstrukturerna med tvärsektoriella systemleverantörer underlättar för en möjlig framtida OPS-struktur
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Lee, Abigail Mary. "The impact of molecular alterations and the immune microenvironment on the natural history of follicular lymphoma including transformation to diffuse large B cell lymphoma." Thesis, Queen Mary, University of London, 2009. http://qmro.qmul.ac.uk/xmlui/handle/123456789/560.
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The natural history of follicular lymphoma is heterogeneous with numerous relapses and remissions over many years. A substantial number of patients suffer an aggressive disease course with death due to disease within 5 years of diagnosis. The prognosis is significantly worse in patients (10-68%) who transform to an aggressive histology. The clinical parameters used to stratify patients with this disease have limited discriminative power and new prognostic biomarkers are required. Insights into the biology of the disease, with identification of potential therapeutic targets are also required. Analysis of paraffin embedded diagnostic FL biopsies from populations of patients at the extremes of overall survival (<5 years and >15 years) demonstrated that expression of CD4 T lymphocytes and a perifollicular location of forkhead box protein P3 were significantly more common in diagnostic biopsies from patients who lived >15 years. Patients with high numbers of intrafollicular CD4 T lymphocytes and higher numbers of CD68 positive macrophages were more likely to undergo rapid transformation to diffuse large B cell lymphoma (DLBCL). Analysis of sequential biopsies pre-and post-transformation from patients with FL who subsequently transformed to DLBCL demonstrated high numbers of CD68 positive macrophages in the majority of cases. The overall survival from transformation was reduced in patients in whom the number of FOXP3 positive T cells decreased/remained low compared to patients in whom the number of FOXP3 positive T cells increased/remained high. Analysis of biopsies pre-and post-transformation from patients with FL who subsequently transformed, identified mutation of TP53 in 28% of cases suggesting a limited role in the process of transformation. The immunocytochemical expression of MDM2, the TP53 regulator, was significantly higher on transformation. The phenotype of transformed FL was confirmed immunocytochemically as Germinal Centre type and two potential drug targets, Aurora Kinase B and nm23, were confirmed as being up-regulated on transformation.
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Keller, David Warren. "The impact of transformational ethics instruction methodologies on student moral judgment in a leadership development course at a large public university in Texas." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1409.
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