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A pattern-based approach for business process modeling / Uma Abordagem Baseada em Padrões para Modelagem de Processos de NegócioThom, Lucinéia Heloisa January 2006 (has links)
Organizações modernas apresentam demandas relacionadas à automação dos seus processos de negócio devido à alta complexidade dos mesmos e à necessidade de maior eficácia na execução. Neste contexto, a tecnologia de workflow tem se mostrado bastante eficiente, principalmente para a automatização dos processos de negócio. No entanto, por ser uma tecnologia emergente e em evolução, workflow apresenta algumas limitações. Ainda que diversos (meta) modelos de workflow tenham sido propostos nos últimos, anos, seus sub-modelos para representação dos aspectos estruturais da organização apresentam baixo poder de expressão. Além disso, a maioria das ferramentas para modelagem de workflow não provêm funcionalidades para definição, consulta e reuso de padrões. Um dos principais problemas é falta de um mapeamento consolidado entre padrões de funções recorrentes em processos de negócio (ex: solicitação de execução de atividade, aprovação de documentos) e (meta) modelos e/ou ferramentas para modelagem de processos de negócio e workflow. Além disso, a maioria das abordagens em padrões de workflow não exploram a completude e necessidade dos seus padrões para modelagem de workflow. A primeira contribuição desta tese é um Modelo Transacional de Processos de Negócio (MTPN) com suporte aos aspectos estruturais da organização. O metamodelo possibilita a criação de (sub-)processos de negócio a partir do reuso de padrões, principalmente com base nestes aspectos. Adicionalmente, o metamodelo sugere a geração automática de padrões através da Linguagem de Execução para Web Services (BPEL4WS). Outra importante contribuição da tese é um conjunto de padrões de workflow representados como atividades de bloco. Cada padrão descreve uma função recorrente em processos de negócio. A mineração de 190 processos de workflow de mais de 10 organizações diferentes provou a existência dos padrões com alto suporte nos processos de workflow analisados. Além disso, o estudo mostrou que o conjunto de padrões é suficiente e necessário para modelar todos os 190 processos investigados. O estudo também resultou em um conjunto de regras de associação. As regras não apenas contribuem para uma melhor definição dos padrões de atividade de bloco, mas também para a combinação destes com padrões de controle de fluxo. / Modern organizations have demands related to the automation of their business processes since such processes are highly complex and need to be efficiently executed. Within this context, the workflow technology has shown to be very effective, mainly in the business process automation. However, as it is an emergent technology and in constant evolution, workflow presents some limitations. Though several workflow (meta) models have been proposed in recent years, their sub-models for organizational structure aspects representation show limited power of expression. On the other hand, most of the current workflow modeling tools do not provide functionalities that enable users to define, query, and reuse workflow patterns properly. One of the main problems is the non-availability of a consolidated mapping between patterns based on recurrent functions found in business processes (e.g., request for activity execution, notification, decision, or approval) and workflow (meta) models or workflow modeling tools. Relying on these problems, the first contribution of this thesis is a Transactional Metamodel of Business Process (TMBP) with support to organizational structure aspects. The metamodel makes feasible to create business (sub-)processes from the reuse of organizational –based workflow patterns. An additional feature of TMBP supports the generation of business (sub-)processes through the Business Process Execution Language for Web Services (BPEL4WS). Other important contribution of this thesis is a set of workflow patterns represented as block activity patterns. Each pattern refers to a recurrent business function frequently found in business processes. The mining of 190 workflow processes of more than 10 different organizations has evidenced the existence of the set of workflow patterns with high support in the workflow processes analyzed. Moreover, it became clear through this study that the set of patterns is both necessary and enough to design all 190 processes that were investigated. As a consequence of the mining process, a set of association rules was identified too. The rules not only help to better define specific workflow patterns, but also combine them with existent control flow patterns. These rules can be useful for building more complex workflows.
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A pattern-based approach for business process modeling / Uma Abordagem Baseada em Padrões para Modelagem de Processos de NegócioThom, Lucinéia Heloisa January 2006 (has links)
Organizações modernas apresentam demandas relacionadas à automação dos seus processos de negócio devido à alta complexidade dos mesmos e à necessidade de maior eficácia na execução. Neste contexto, a tecnologia de workflow tem se mostrado bastante eficiente, principalmente para a automatização dos processos de negócio. No entanto, por ser uma tecnologia emergente e em evolução, workflow apresenta algumas limitações. Ainda que diversos (meta) modelos de workflow tenham sido propostos nos últimos, anos, seus sub-modelos para representação dos aspectos estruturais da organização apresentam baixo poder de expressão. Além disso, a maioria das ferramentas para modelagem de workflow não provêm funcionalidades para definição, consulta e reuso de padrões. Um dos principais problemas é falta de um mapeamento consolidado entre padrões de funções recorrentes em processos de negócio (ex: solicitação de execução de atividade, aprovação de documentos) e (meta) modelos e/ou ferramentas para modelagem de processos de negócio e workflow. Além disso, a maioria das abordagens em padrões de workflow não exploram a completude e necessidade dos seus padrões para modelagem de workflow. A primeira contribuição desta tese é um Modelo Transacional de Processos de Negócio (MTPN) com suporte aos aspectos estruturais da organização. O metamodelo possibilita a criação de (sub-)processos de negócio a partir do reuso de padrões, principalmente com base nestes aspectos. Adicionalmente, o metamodelo sugere a geração automática de padrões através da Linguagem de Execução para Web Services (BPEL4WS). Outra importante contribuição da tese é um conjunto de padrões de workflow representados como atividades de bloco. Cada padrão descreve uma função recorrente em processos de negócio. A mineração de 190 processos de workflow de mais de 10 organizações diferentes provou a existência dos padrões com alto suporte nos processos de workflow analisados. Além disso, o estudo mostrou que o conjunto de padrões é suficiente e necessário para modelar todos os 190 processos investigados. O estudo também resultou em um conjunto de regras de associação. As regras não apenas contribuem para uma melhor definição dos padrões de atividade de bloco, mas também para a combinação destes com padrões de controle de fluxo. / Modern organizations have demands related to the automation of their business processes since such processes are highly complex and need to be efficiently executed. Within this context, the workflow technology has shown to be very effective, mainly in the business process automation. However, as it is an emergent technology and in constant evolution, workflow presents some limitations. Though several workflow (meta) models have been proposed in recent years, their sub-models for organizational structure aspects representation show limited power of expression. On the other hand, most of the current workflow modeling tools do not provide functionalities that enable users to define, query, and reuse workflow patterns properly. One of the main problems is the non-availability of a consolidated mapping between patterns based on recurrent functions found in business processes (e.g., request for activity execution, notification, decision, or approval) and workflow (meta) models or workflow modeling tools. Relying on these problems, the first contribution of this thesis is a Transactional Metamodel of Business Process (TMBP) with support to organizational structure aspects. The metamodel makes feasible to create business (sub-)processes from the reuse of organizational –based workflow patterns. An additional feature of TMBP supports the generation of business (sub-)processes through the Business Process Execution Language for Web Services (BPEL4WS). Other important contribution of this thesis is a set of workflow patterns represented as block activity patterns. Each pattern refers to a recurrent business function frequently found in business processes. The mining of 190 workflow processes of more than 10 different organizations has evidenced the existence of the set of workflow patterns with high support in the workflow processes analyzed. Moreover, it became clear through this study that the set of patterns is both necessary and enough to design all 190 processes that were investigated. As a consequence of the mining process, a set of association rules was identified too. The rules not only help to better define specific workflow patterns, but also combine them with existent control flow patterns. These rules can be useful for building more complex workflows.
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Méthodes de conception par optimisation robuste et fiable de dispositifs électromagnétiques / Methods for robust and reliability-based design optimization of electromagnetic devicesDeng, Siyang 22 January 2018 (has links)
Cette thèse porte sur les problèmes d'optimisation robustes et fiables avec l'incertitude d'entrée.Tout d'abord, les différentes catégories de méthodes d'optimisation stochastique pour traiter l'incertitude sont présentées. Ces méthodes visent à trouver une solution plus robuste et fiable en minimisant la variance de l'objectif et/ou en réduisant la probabilité de violer les contraintes en différentes manières. Chaque catégorie a diverses approches et après la comparaison, les plus efficaces sont sélectionnées.Cependant, comme ces méthodes augmentent le nombre d'évaluations par rapport à l'optimisation déterministe et nécessitent l'information de gradient qui peut être bruyante fournie par des modèles lourds comme les modèles d'éléments finis, elles ne conviennent pas aux modèles qui prennent du temps. Des stratégies de méta-modèles basées sur le krigeage sont proposées dans ce manuscrit car elles pourraient utiliser la détermination d'une petite taille d’échantillons pour approcher des fonctions complexes et donner des dérivés précis. La fonction objectif initiale et les contraintes sont progressivement remplacées par des méta-modèles de krigeage utilisant le critère d’enrichissement pour ajouter des échantillons dans le processus d'optimisation. Différentes stratégies compris le choix du critère et le positionnement de l'enrichissement de l'échantillon pour chaque catégorie sont comparées et mettent en évidence les plus efficaces.Ensuite, les approches d'optimisation développées dans ce travail de recherche sont appliquées aux modèles analytiques et aux éléments finis d'un transformateur pour résoudre des problèmes d'optimisation électromagnétique. / This PhD thesis deals with the robust and reliability-based optimization problems under input uncertainty.First, the different categories of stochastic optimization methods to treat the uncertainty are presented. These methods aim to find a more robust and/or reliable solution by minimize the variance of objective and reducing the probability to violate the constraints in different ways. Each categories has various approaches and after comparison, the most effective ones are selected.However, as these methods increase the number of evaluation than deterministic optimization and need the gradient information which may be noisy provided by time-consuming models like finite element models, they are not suitable for the heavy models. So kriging-based meta-model strategies are proposed in this manuscript as it could use the determination of small size sample to approach complex functions and give accurate derivatives. The original objective function and constraints are progressively replaced by kriging meta-models using infill sampling criterion to add samples in the process of optimization. Different strategies including the choice of the criterion and the positioning of sample enrichment for each categories are compared and highlight the most effective ones.Then the optimization approaches developed within this research work are applied to the analytic and finite element models of a transformer for solving an electromagnetic optimization problems.
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A pattern-based approach for business process modeling / Uma Abordagem Baseada em Padrões para Modelagem de Processos de NegócioThom, Lucinéia Heloisa January 2006 (has links)
Organizações modernas apresentam demandas relacionadas à automação dos seus processos de negócio devido à alta complexidade dos mesmos e à necessidade de maior eficácia na execução. Neste contexto, a tecnologia de workflow tem se mostrado bastante eficiente, principalmente para a automatização dos processos de negócio. No entanto, por ser uma tecnologia emergente e em evolução, workflow apresenta algumas limitações. Ainda que diversos (meta) modelos de workflow tenham sido propostos nos últimos, anos, seus sub-modelos para representação dos aspectos estruturais da organização apresentam baixo poder de expressão. Além disso, a maioria das ferramentas para modelagem de workflow não provêm funcionalidades para definição, consulta e reuso de padrões. Um dos principais problemas é falta de um mapeamento consolidado entre padrões de funções recorrentes em processos de negócio (ex: solicitação de execução de atividade, aprovação de documentos) e (meta) modelos e/ou ferramentas para modelagem de processos de negócio e workflow. Além disso, a maioria das abordagens em padrões de workflow não exploram a completude e necessidade dos seus padrões para modelagem de workflow. A primeira contribuição desta tese é um Modelo Transacional de Processos de Negócio (MTPN) com suporte aos aspectos estruturais da organização. O metamodelo possibilita a criação de (sub-)processos de negócio a partir do reuso de padrões, principalmente com base nestes aspectos. Adicionalmente, o metamodelo sugere a geração automática de padrões através da Linguagem de Execução para Web Services (BPEL4WS). Outra importante contribuição da tese é um conjunto de padrões de workflow representados como atividades de bloco. Cada padrão descreve uma função recorrente em processos de negócio. A mineração de 190 processos de workflow de mais de 10 organizações diferentes provou a existência dos padrões com alto suporte nos processos de workflow analisados. Além disso, o estudo mostrou que o conjunto de padrões é suficiente e necessário para modelar todos os 190 processos investigados. O estudo também resultou em um conjunto de regras de associação. As regras não apenas contribuem para uma melhor definição dos padrões de atividade de bloco, mas também para a combinação destes com padrões de controle de fluxo. / Modern organizations have demands related to the automation of their business processes since such processes are highly complex and need to be efficiently executed. Within this context, the workflow technology has shown to be very effective, mainly in the business process automation. However, as it is an emergent technology and in constant evolution, workflow presents some limitations. Though several workflow (meta) models have been proposed in recent years, their sub-models for organizational structure aspects representation show limited power of expression. On the other hand, most of the current workflow modeling tools do not provide functionalities that enable users to define, query, and reuse workflow patterns properly. One of the main problems is the non-availability of a consolidated mapping between patterns based on recurrent functions found in business processes (e.g., request for activity execution, notification, decision, or approval) and workflow (meta) models or workflow modeling tools. Relying on these problems, the first contribution of this thesis is a Transactional Metamodel of Business Process (TMBP) with support to organizational structure aspects. The metamodel makes feasible to create business (sub-)processes from the reuse of organizational –based workflow patterns. An additional feature of TMBP supports the generation of business (sub-)processes through the Business Process Execution Language for Web Services (BPEL4WS). Other important contribution of this thesis is a set of workflow patterns represented as block activity patterns. Each pattern refers to a recurrent business function frequently found in business processes. The mining of 190 workflow processes of more than 10 different organizations has evidenced the existence of the set of workflow patterns with high support in the workflow processes analyzed. Moreover, it became clear through this study that the set of patterns is both necessary and enough to design all 190 processes that were investigated. As a consequence of the mining process, a set of association rules was identified too. The rules not only help to better define specific workflow patterns, but also combine them with existent control flow patterns. These rules can be useful for building more complex workflows.
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Regression models to assess the thermal performance of Brazilian low-cost houses: consideration of solar incidence and shading devices / Regression Models to Assess the Thermal Performance of Brazilian Low-Cost Houses: Consideration of Solar Incidence and Shading DevicesCamila Chagas Anchieta 01 February 2016 (has links)
Building performance simulation (BPS) tools are significant and helpful during all design stages, especially during the early ones. However, there are obstacles to the full implementation and use of such tools, causing them not to become an effective part of the design process. In order to overcome this barrier, this research is presented, with the creation of regression models (meta-models) that allow to predict the discomfort by heat and/or by cold in a Brazilian low-cost house (LCH) in three distinct bioclimatic zones in Brazil, represented by the cities of Curitiba/PR, São Paulo/SP and Manaus/AM. The focus of this work was to analyze the impact of solar incidence and shading devices on thermal comfort by applying the meta-models. The method consisted in a) collecting data from projects referring to the type of building aforementioned to aid in the creation of the base model; b) definition of the key parameters and their ranges to be varied; c) simulations run on EnergyPlus using the Monte Carlo method to randomly create parameters combinations within their defined ranges; d) regression analysis and metamodels elaboration, followed by their validation with reliability tests; and lastly, e) a case study, consisting in applying the meta-models to a standard LCH to verify the impact of shading devices in a unit in regards to thermal comfort and the their potential as support tool in the design process. In general, all R2 values for the meta-models were above 0.95, except for the ones for São Paulo and Curitiba for discomfort by heat, 0.74 and 0.61, respectively. In regards to the case study, the meta-models predicted a decrease of approximately 50% in discomfort by heat for Manaus when a given combination of orientation, quantity and size of the devices was used. For the remaining locations, the meta-models predicting discomfort by heat and by cold require further investigation to properly assess some unexpected predictions and the meta-models sensitivity to the parameters related to shading devices. / Ferramentas de simulação computacional são importantes e uteis durante todas as etapas de projeto, especialmente durante as iniciais. No entanto. Há obstáculos para a completa implementação e uso de tais ferramentas, fazendo com que não sejam uma parte efetiva do processo de projeto. Para superar esta barreira, esta pesquisa é apresentada, com a criação de modelos de regressão (meta-modelos) que permitem a predição do desconforto por frio e/ou por calor em uma habitação de interesse social (HIS) no Brasil em três zonas bioclimáticas, representadas pelas cidades de Curitiba/PR, São Paulo/SP e Manaus/AM. O foco deste trabalho foi analisar o impacto da incidência solar e das proteções solares no conforto térmico utilizando os meta-modelos. O método consistiu em a) coletar dados referentes ao tipo de edifício mencionado para auxiliar na criação do modelo de base; b) a definição dos parâmetros chave e suas faixas de variação; c) simulações no EnergyPlus usando o método de Monte Carlo para aleatoriamente combinar valores de parâmetros dentro de suas faixas; d) análise de regressão e elaboração dos meta-modelos, seguida da validação dos mesmos por testes de confiabilidade; e por fim, e) um estudo de caso, consistindo na aplicação dos meta-modelos a uma HIS padrão para verificar o impacto das proteções solares em uma unidade em relação ao conforto térmico da mesma, assim como o potencial dos meta-modelos em serem utilizados como uma ferramenta de auxílio nas fases iniciais de projeto. No geral, todos os valores de R2 foram acima de 0.95, exceto para os meta-modelos de São Paulo e Curitiba para desconforto por calor, com 0.74 e 0.61, respectivamente. Em relação ao estudo de caso, os meta-modelos previram uma queda de aproximadamente 50% no desconforto por calor para Manaus, dada uma combinação entre orientação, quantidade e dimensão das proteções. Para as demais localidades, os meta-modelos prevendo desconforto por frio e por calor requerem maiores estudos para avaliar predições inesperadas e a sensibilidade dos meta-modelos em relação aos parâmetros de proteções solares.
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Concevoir et partager des workflows d’analyse de données : application aux traitements intensifs en bioinformatique / Design and share data analysis workflows : application to bioinformatics intensive treatmentsMoreews, François 11 December 2015 (has links)
Dans le cadre d'une démarche d'Open science, nous nous intéressons aux systèmes de gestion de workflows (WfMS) scientifiques et à leurs applications pour l'analyse de données intensive en bioinformatique. Nous partons de l'hypothèse que les WfMS peuvent évoluer pour devenir des plates-formes pivots capables d'accélérer la mise au point et la diffusion de méthodes d'analyses innovantes. Elles pourraient capter et fédérer autour d'une thématique disciplinaire non seulement le public actuel des consommateurs de services mais aussi celui des producteurs de services. Pour cela, nous considérons que ces environnements doivent à la fois être adaptés aux pratiques des scientifiques concepteurs de méthodes et fournir un gain de productivité durant la conception et le traitement. Ces contraintes nous amènent à étudier la capture rapide des workflows, la simplification de l'intégration des tâches techniques, comme le parallélisme nécessaire au haut-débit, et la personnalisation du déploiement. Tout d'abord, nous avons défini un langage graphique DataFlow expressif, adapté à la capture rapide des workflows. Celui-ci est interprétable par un moteur de workflows basé sur un nouveau modèle de calcul doté de performances élevées, obtenues par l'exploitation des multiples niveaux de parallélisme. Nous présentons ensuite une approche de conception orientée modèle qui facilite la génération du parallélisme de données et la production d'implémentations adaptées à différents contextes d'exécution. Nous décrivons notamment l'intégration d'un métamodèle des composants et des plates-formes, employé pour automatiser la configuration des dépendances des workflows. Enfin, dans le cas du modèle Container as a Service (CaaS), nous avons élaboré une spécification de workflows intrinsèquement diffusable et ré-exécutable. L'adoption de ce type de modèle pourrait déboucher sur une accélération des échanges et de la mise à disposition des chaînes de traitements d'analyse de données. / As part of an Open Science initiative, we are particularly interested in the scientific Workflow Management Systems (WfMS) and their applications for intensive data analysis in bioinformatics. We start from the assumption that WfMS can evolve to become efficient hubs able to speed up the development and the dissemination of innovative analysis methods. These software platforms could rally and unite not only the current stakeholders, who are service consumers, but also the service producers, around a disciplinary theme. We therefore consider that these environments must be both adapted to the practices of the scientists who are method designers and also enhanced with increased productivity during design and treatment. These constraints lead us to study the rapid capture of workflows, the simplification of technical tasks integration, like parallelisation and the deployment customization. First, we define an expressive graphic worfklow language, adapted to the quick capture of workflows. This is interpreted by a workflow engine based on a new model of computation with high performances obtained by the use of multiple levels of parallelism. Then, we present a Model-Driven design approach that facilitates the data parallelism generation and the production of suitable implementations for different execution contexts. We describe in particular the integration of a components and platforms meta-model used to automate the configuration of workflows’ dependencies. Finally, in the case of the cloud model Container as a Service (CaaS), we develop a workflow specification intrinsically re-executable and readily disseminatable. The adoption of this kind of model could lead to an acceleration of exchanges and a better availability of data analysis workflows.
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Parallélisation de simulateur DEVS par métamodélisation et transformation de modèle / DEVS simulator parallelization by metamodeling and model transformationTogo, Hamidou 23 December 2015 (has links)
Cette thèse propose une approche d’ingénierie consistant à paralléliser des simulateurs DEVS existants, sans être obligé de modifier les algorithmes de l’implémentation initiale, mais en injectant des composants additionnels adaptés au protocole de communication intercomposants en vigueur. Les algorithmes de simulation de ces nouveaux composants appelés « Manteaux », sont définis. Une démarche d’ingénierie permettant de systématiser le passage d’une implémentation à sa contrepartie parallèle et distribuée est ensuite proposée. Cette démarche s’appuie sur les principes de méta modélisation et de transformation de modèles inspirés de l’Ingénierie Dirigée par les Modèles (IDM). Sa généricité en garantit la réutilisabilité avec tout simulateur séquentiel DEVS. / This thesis proposes an engineering approach to parallelize existing DEVS simulators without having to modify the algorithms of the initial implementation, but by injecting additional components suitable for inter-component communication protocol into force. The simulation algorithms of these new components called "Coats" are defined.An engineering approach to systematize the passage from one implementation to its counterpart parallel and distributed is then proposed. This approach is based on metamodeling and models transformation principles inspired of Model Driven Engineering (MDE). Its genericity guarantees the reusability with any sequential DEVS simulator.
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Impact of Structure Modification on Cardiomyocyte FunctionalityCosi, Filippo Giovanni 27 February 2020 (has links)
No description available.
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Optimum Design of Axial Flux PM Machines based on Electromagnetic 3D FEATaran, Narges 01 January 2019 (has links)
Axial flux permanent magnet (AFPM) machines have recently attracted significant attention due to several reasons, such as their specific form factor, potentially higher torque density and lower losses, feasibility of increasing the number of poles, and facilitating innovative machine structures for emerging applications. One such machine design, which has promising, high efficiency particularly at higher speeds, is of the coreless AFPM type and has been studied in the dissertation together with more conventional AFPM topologies that employ a ferromagnetic core.
A challenge in designing coreless AFPM machines is estimating the eddy current losses. This work proposes a new hybrid analytical and numerical finite element (FE) based method for calculating ac eddy current losses in windings and demonstrates its applicability for axial flux electric machines. The method takes into account 3D field effects in order to achieve accurate results and yet greatly reduce computational efforts. It is also shown that hybrid methods based on 2D FE models, which require semi-empirical correction factors, may over-estimate the eddy current losses. The new 3D FE-based method is advantageous as it employs minimum simplifications and considers the end turns in the eddy current path, the magnetic flux density variation along the effective length of coils, and the field fringing and leakage, which ultimately increases the accuracy of simulations.
After exemplifying the practice and benefits of employing a combined design of experiments and response surface methodology for the comparative design of coreless and conventional AFPM machines with cores, an innovative approach is proposed for integrated design, prototyping, and testing efforts. It is shown that extensive sensitivity analysis can be utilized to systematically study the manufacturing tolerances and identify whether the causes for out of specification performance are detectable.
The electromagnetic flux path in AFPM machines is substantially 3D and cannot be satisfactorily analyzed through simplified 2D simulations, requiring laborious 3D models for performance prediction. The use of computationally expensive 3D models becomes even more challenging for optimal design studies, in which case, thousands of candidate design evaluations are required, making the conventional approaches impractical. In this dissertation a new two-level surrogate assisted differential evolution multi-objective optimization algorithm (SAMODE) is developed in order to optimally and accurately design the electric machine with a minimum number of expensive 3D design evaluations.
The developed surrogate assisted optimization algorithm is used to comparatively and systematically design several AFPM machines. The studies include exploring the effects of pole count on the machine performance and cost limits, and the systematic comparison of optimally designed single-sided and double-sided AFPM machines. For the case studies, the new optimization algorithm reduced the required number of FEA design evaluations from thousands to less than two hundred.
The new methods, developed and presented in the dissertation, maybe directly applicable or extended to a wide class of electrical machines and in particular to those of the PM-excited synchronous type. The benefits of the new eddy current loss calculation and of the optimization method are mostly relevant and significant for electrical machines with a rather complicated magnetic flux path, such is the case of axial flux and of transvers flux topologies, which are a main subject of current research in the field worldwide.
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Meta-Modelling Based Design Optimization of Gas Turbine Blade Cooling ChannelsSharma, Namita January 2021 (has links)
The aim of this paper is to investigate the use of Machine Learning to accelerate the processof gas turbine design optimization. Traditionally, the process simulations involved inoptimization are performed using commercial Computational Fluid Dynamics (CFD) softwaretools to find the best combinations of design parameters under specific conditionsand operational constraints. However, such simulations can become computationally toocomplex and slow for routine analysis of component designs. To address this challenge, ameta-modeling approach is developed in this study that uses "computer simulation data"collected from a small number of simulation runs. The trained metamodel is then used topredict the metal temperatures of the turbine blades to approximate the complex thermodynamicsimulations. The focus of this research is to accurately model the cooling processof a turbine by analyzing the effect of changing the diameters of the cooling holes drilledinto the gas turbine blades on the output metal temperatures.
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