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Otimização dos armazenadores de energia elétrica de um veículo híbrido em função do ciclo de condução : Optimization of the electric energy storage systems of a hybrid electric vehicle in function of the driving cycle / Optimization of the electric energy storage systems of a hybrid electric vehicle in function of the driving cycleSanticiolli, Fabio Mazzariol, 1989- 24 August 2018 (has links)
Orientador: Franco Giuseppe Dedini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-24T19:38:02Z (GMT). No. of bitstreams: 1
Santiciolli_FabioMazzariol_M.pdf: 3517962 bytes, checksum: dce3e151594966ee424d36ea933a24f9 (MD5)
Previous issue date: 2014 / Resumo: Este trabalho tem a intenção de contribuir com o projeto de veículos elétricos híbridos com foco no compromisso entre economia de combustível e custo de rodagem. Com esta finalidade, faz-se uma revisão sobre a modelagem de alguns dos principais subsistemas dos veículos elétricos híbridos, como ultracapacitores, baterias, motores elétricos e motores de combustão interna, bem como sobre as formas de associação destes subsistemas em torno do veículo completo. Também se revisam os fatores que compõe a dinâmica veicular longitudinal como o Arrasto Aerodinâmico, a Resistência à Rolagem e a Resistência ao Aclive. Após o domínio dos subsistemas mais importantes e da dinâmica veicular, montam-se modelos matemáticos de veículos completos e em torno de simulações computacionais. Neste estudo fazem-se quatro tipos de simulações principais, uma relativa a um veículo convencional e outras três versões alternativas hibridizadas, variando-se o modo de associação entre baterias, ultracapacitores, choppers e motores elétricos. Em sequência, para cada versão otimizam-se os armazenadores em função da capacidade de tração elétrica e do ciclo brasileiro normatizado de condução urbana. Por fim faz-se uma análise crítica dos resultados / Abstract: This research intends to contribute to the design of hybrid electric vehicles focusing on compromise between fuel economy and running costs. For this purpose, it contains a review on the modeling of some of the main subsystems of hybrid electric vehicles, such as ultracapacitors, batteries, electric motors and internal combustion engines, as well as the forms of associating these subsystems around the whole vehicle. It also revises the factors that compose the longitudinal vehicle dynamics like Aerodynamic Drag, Rolling Resistance and Uphill Resistance. After the dominance of the main subsystems and vehicle dynamics, it describes the mathematical models of complete vehicles and around computer simulations. This study contains four main types of simulations, relative to a conventional vehicle and three other alternatives hybridized versions, varying the mode of association between batteries, ultracapacitors, choppers and electric motors. In sequence, to the amount of electric traction and the Brazilian standardized urban driving cycle are the parameters that command the optimization of each version is the energy stores. Finally it finishes in a critical analysis of the results / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
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Fastpris med Dynamic Systems Development Method (DSDM) : Fungerar DSDM som projektstyrningsmodell i fastprisprojekt?Sjöstedt, Katarina January 2007 (has links)
Enligt Standish Group är det endast cirka 35 % av alla systemutvecklingsprojekt som avslutas på ett lyckat sätt när det gäller tid, budget och resurser. Inom systemutveckling är fastprisprojekt, där systemets kostnad är förbestämd, allt mer populärt. Dynamic Systems Development Method (DSDM) är en modell för utveckling som fokuserar på fasta resurser och tid med funktionalitet som den flexibla variabeln. Syftet med den här uppsatsen är att se om man kan driva fastprisprojekt med en modell som DSDM på ett sätt som gör det till en bra lösning för både beställare och leverantör. Min slutsats är att det största problemet med DSDM är att få beställaren att godkänna den som projektmodell. Ett annat stort problem är att många projekt med DSDM blir stressiga eftersom tiden är fast. Flexibiliteten med funktionaliteten räcker med andra ord inte till. Önskvärda förbättringar inom DSDM är att ge mer underlag för hur man skall få en ny beställare att godkänna modellen. Dessutom att tillhandahålla guidelines för hur man kan hantera ett projekt med många och detaljerade krav. En annan viktig faktor som måste förbättras är hur man får projekt med DSDM att bli mindre stressiga. DSDM är en modell som uppskattas av dem som har erfarenhet av den och som anses resultera i lyckade projekt, för både beställare och leverantör. Mina slutsatser är därför att DSDM kan fungera bra men att det ställer höga krav på projektet. Både beställare och leverantör måste vara engagerade. Beställaren måste kunna prioritera sina krav och räkna med att en del funktionalitet inte kommer med. Dessutom måste det finnas stor användarinvolvering och projektgruppen måste ha beslutsmandat.
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Integrabilidade e ressonâncias : aplicações dos métodos de Melnikov / Integrability and resonances : applications of the Melnikov methodsDepetri, Gabriela Iunes, 1987- 28 August 2018 (has links)
Orientadores: Alberto Vazquez Saa, Marcus Aloizio Martinez de Aguiar / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-28T09:56:07Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: Nesta tese estudamos, através dos métodos de Melnikov, o comportamento de dois sistemas dinâmicos que são exemplos paradigmáticos de integrabilidade em Mecânica Clássica, quando sujeitos a perturbações: (i) o pêndulo plano simples, no caso em que o pivô oscila harmonicamente ao longo de um eixo inclinado em relação à direção vertical; e (ii) o problema de Kepler, no caso em que a massa do corpo que gera o campo gravitacional possui momento de quadrupolo. Para o pêndulo simples parametricamente excitado ao longo de uma direção inclinada, analisamos a ocorrência de caos homoclínico, e também de oscilações subharmônicas, com o objetivo de comparar os nossos resultados com aqueles conhecidos para o caso em que a excitação ocorre ao longo da direção vertical. Verificamos que o critério para a ocorrência de caos homoclínico é numericamente muito próximo em ambos os casos, mas em relação à ocorrência de soluções oscilatórias subharmônicas notamos uma diferença relevante devido à quebra de simetria nas equações do movimento do sistema: enquanto para o caso vertical a condição de Melnikov garante apenas a existência de oscilações subharmônicas de ordem par, nada se podendo afirmar em relação às subharmônicas de ordem ímpar, para o caso inclinado ela garante a ocorrência de todo o espectro de ressonâncias. Sabemos que apesar de alguns autores reportarem a ocorrência de oscilações subharmônicas de ordem ímpar no caso vertical, estas são muito raras e difíceis de ser encontradas, ao contrário do que acontece com as oscilações subharmônicas de ordem par. Entretanto, neste trabalho mostramos, através de simulações numéricas e dados experimentais, que no caso inclinado elas podem ser encontradas trivialmente em regiões de ressonância, provavelmente porque as bacias de atração dessas órbitas são de natureza diferente em cada caso. Os dados experimentais apresentados nesta tese foram tomados no Laboratório de Fenômenos Não-Lineares (LFNL) do Instituto de Física da Universidade de São Paulo (IFUSP), em colaboração com o Prof. Dr. José Carlos Sartorelli. Para o problema de Kepler, as inomogeneidades na distribuição da massa do corpo que gera o campo gravitacional são descritas através de expansão multipolar. Sabemos o termo de dipolo mantém o sistema integrável. O termo de quadrupolo, por sua vez, pode provocar a ocorrência de caos no sistema. Em um trabalho de 2001, Géron e Letelier afirmam, baseados em simulações numéricas, que no caso em que a perturbação é oblata, o sistema é integrável, enquanto se a perturbação é prolata, o sistema pode apresentar caos. Entretanto, em um trabalho mais recente, Letelier it et al mostram, também numericamente, que ambos os casos podem apresentar trajetórias caóticas. Com o nosso trabalho, resolvemos esta inconsistência na literatura, determinando que a ocorrência de caos de fato não depende do tipo da deformação. Nosso resultado está de acordo com o caso mais geral estudado na literatura / Abstract: In this PhD thesis we study, through the Melnikov methods, the behaviour of two dynamical systems that are paradigms of integrability in Classical Dynamics, when subject to perturbations: (i) the planar simple pendulum, in the case that the pivot oscillates harmonically along a tilted direction; and (ii) the Kepler problem, in the case that the mass of the body generating the gravitational field is not homogeneous, but instead presents a quadrupole moment term. To the simple pendulum parametrically excited along a tilted direction, we analyze the occurence of homoclinic chaos, and also of subharmonic oscillatory solutions, willing to compare our results with those already known in the literature in the case the excitation is along the vertical direction. We verified the criterium to the occurence of homoclinic chaos is numerically very close in both cases, but considering the occurence of subharmonic oscillatory orbits we noted an important difference due to the symmetry breaking of the equations of motion describing the system: while in the vertical case the Melnikov conditions can only assure the occurence of even subharmonic oscillations (nothing can be said about the odd subharmonic oscillating solutions), in the tilted case it guarantees the occurence of all subharmonic oscillations. Still some authors report the occurence of odd subharmonic oscillations in the vertical case, unlike the even oscillatory orbits, those are very rare and hard to find. In this work we show, through numeric simulations and experimental data, that in the tilted case they can be easily found in resonance regions, probably because their basins of attraction have different characteristics in both cases. The experimental data presented in this thesis were taken at the Laboratory of Nonlinear Phenomena (LFNL) at the Physics Institute of the University of São Paulo (IFUSP), in collaboration with Prof. Dr. José Carlos Sartorelli. To the Kepler problem, the inhomogeneities in the mass distribution of the heavy body generating the gravitational field are described through multipolar expansion.
We know the dipole term keeps the integrability of the system. The quadrupole term, instead, can lead to the occurence of chaotic orbits in the system. In 2001, Géron and Letelier, based on numeric simulations, assert that the system is integrable if the perturbation is of oblate type, but chaotic if it is of prolate type. However, in a more recent work, Letelier et al show, also via numeric computation, that both cases can present chaotic trajectories. We solve this inconsistency in the literature by determining that the occurence of chaos in fact does not depend on the deformation type. Our results agree with the more general case studied in the literature / Doutorado / Física / Doutora em Ciências / 141762/2011-0 / CNPQ
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[pt] MODELAGEM DE UM SIMULADOR DE MOVIMENTOS PARA VEÍCULOS TERRESTRES EM ESCALA / [en] MODELING OF A SCALE GROUND VEHICLES MOTION SIMULATORROBERTH WALDO ANGULO LLERENA 10 April 2012 (has links)
[pt] No presente trabalho desenvolveu-se o projeto básico de um Simulador de Movimentos em Escala, que é um equipamento utilizado para reproduzir as excitações de base provocadas pelo pavimento sobre o qual um veículo em escala trafega.
Utilizando modelos consagrados na literatura, obteve-se a representação matemática do Simulador, que é tratado como 3 subsistemas acoplados entre si, mediante a aplicação de um procedimento baseado no Fluxo de Potência.
Para o tratamento dos modelos em escala é empregada a Teoria de Similaridade, através da qual são determinados números adimensionais que relacionam o sistema real com o seu equivalente reduzido ou ampliado. São apresentadas 3 metodologias, das quais duas tradicionais, e uma outra que é conhecida como Método por Inspeção. Aplicam-se estes procedimentos a modelos de veículos com 1, 2, 4 e 7 graus de liberdade. Emprega-se também a Análise Dimensional para achar um modelo em escala do Simulador e do sistema completo, isto é um conjunto Simulador – Veículo acoplado.
Para todos os casos são realizadas simulações para os modelos real e em escala, utilizando parâmetros típicos encontrados na literatura ou em manuais de operação de equipamentos semelhantes, com o objetivos de verificar o comportamento dos sistemas, determinar a influência da redução ou ampliação do tamanho, e validar os procedimentos empregados. / [en] In this work a Scale Ground Simulator was developed. This is na equipment used to reproduce the base motion in a vehicle, due the Road where it is running.
Using a procedure based on the Power flow, coupling the 3 main Simulator subsystems, a mathematical representation for the Simulator was obtained, from classical models mentioned in the bibliography.
The scale models treatment was perfomed using the Similarity Theory, that permits the determination of non dimensional numbers relating the real system with its equivalent reduced or amplified. It was presented 3 methodologies, two of them are traditional and other one which is known as Inspection Method. These procedures were applied to 1, 2, 4, and 7 degrees of freedom vehicle models. Dimensional Analysis is also used to find scale models for the Simulator and for the complete system, i.e. the coupled set Simulator – Vehicle.
Simulations were made for all situations, in real and scale models, using typical parameters found in literature or in equipment operation manuals, aiming to verify the systems performance, to determine the size reduction or amplification influence of and to validate the procedures presented.
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An Application of the Unscented Kalman Filter for Spacecraft Attitude Estimation on Real and Simulated Light Curve DataRush, Kent A 01 July 2020 (has links) (PDF)
In the past, analyses of lightcurve data have been applied to asteroids in order to determine their axis of rotation, rotation rate and other parameters. In recent decades, these analyses have begun to be applied in the domain of Earth orbiting spacecraft. Due to the complex geometry of spacecraft and the wide variety of parameters that can influence the way in which they reflect light, these analyses require more complex assumptions and a greater knowledge about the object being studied. Previous investigations have shown success in extracting attitude parameters from unresolved spacecraft using simulated data. This paper presents a focused attempt to derive attitude parameters using an Unscented Kalman Filter from both simulated and real data provided by Lockheed Martin Space.
This thesis characterizes and presents the differences in performance between three simulated geometries in low, medium, and geostationary orbit in both cases where they are spinning about a constant axis and in cases in which they are tumbling.
Additionally, this thesis hypothesizes and tests the idea that a predictable and extraneous angular velocity solution exists which is the reflection of the true solution about the plane defined by the sun and observation vectors. This thesis encountered multiple instances of this type solution appearing in simulation and provides an example as well as a visualization.
Finally, this thesis demonstrates the ability to converge to a solution from real data although there were large discrepancies between the measurement model and the data. This thesis discusses the validity of these solutions and sources of error.
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Resource Management in Complex and Dynamic EnvironmentsRaunak, Mohammad Salimullah 01 September 2009 (has links)
Resource management is at the heart of many diverse science and engineering research areas. Although the general notion of what constitutes a resource entity seems similar in different research areas, their types, characteristics, and constraints governing their behavior are vastly different depending on the particular domain of research and the nature of the research itself. Often research related to resource modeling and management focus on largely homogeneous resources in a relatively simplified model of the real world. The problem becomes much more challenging to deal with when working with a complex real life domain with many heterogeneous resource types and intricate constraints. In this dissertation, we have looked at the modeling and management of resource instances and tried to develop a better sense of what makes them different from other objects in a system. As part of this work, We formally define the general resource management problem, identify its major sub problem areas and their associated complexities, and look at the problem in the context of a particularly complex and dynamic environment, namely the emergency department (ED) of a hospital. We propose an approach to the problem and some of its complexities by presenting an overall unifying view, as well as tools and methods for dealing with, this pervasive, yet surprisingly under examined, type of entity, i.e. resources. We have discovered that one of the discerning characteristics of resource instances in complex and dynamic environments seem to be their dynamic capability profile that may changes depending on system context. This, in turn, often results in complex substitutability relationship amongst resource instances. We have identified four major sub-problem areas that can provide a holistic view of any resource management service. These separate, yet interconnected, areas of con- cerns include resource modeling, resource request specification, resource constraint management, and resource allocation. Resource modeling involves capturing of re- source characteristics and their potentially dynamic behavior. Request definitions describe how resource users specify requirements for resources in a particular do- main. In most domains, there are constraints that need to be satisfied while serving resources to fulfill specific requests. The fourth area of concerns, the allocation of resources, is a complex component with multiple subcomponents that closely inter- act with each other. In this thesis, we have described an architecture for a exible resource management service based on the above described separation of concerns. We have proposed some simple, yet effective, techniques for modeling resource in- stances, specifying resource requests, specifying and managing resource constraints, and allocating resource instances to meet a resource demand characterized by a con- tinuous stream of requests. Using our proposed design, we have developed ROMEO, a resource management service and customized it to serve a task coordination frame- work based on Litlle-JIL process definition language. Our work then concentrated on evaluating the effectiveness of ROMEO in supporting simulations and executions of complex processes. For this evaluation purpose, we developed a simulation infras- tructure named JSim on top of Juliette, Little-JIL's execution environment. We ran a variety of simulations of patient care processes in EDs using our ROMEO-JSim infrastructure. We also used ROMEO to support the actual execution (rather than just the simulation) of a large mediation process. A central premise, hypothesized and explored in this thesis, is a novel way of thinking about resource instances in dynamic domains, namely defining them with a set of guarded capabilities, some of which may be dependent on the execution state of the system. This has led us to think about how to represent execution states of a running system and what types of system state information might be important for representing the guard functions on the capabilities of a resource instance that define the resource instance's ability to satisfy a request at a given execution state of the system. We have also identified a small set of common types of attributes of resource instances that seem able to support specification of a large variety of resource instances in complex domains. We believe that our research supports our hypothesis that specifying resource instances as having sets of guarded capabilities provides a useful abstraction for modeling many of the complex dynamic behaviors of resource instances in such domains as hospital EDs.
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DISASTER'S WAKE: THE ROLE OF ARCHITECTURE IN TRAUMA RECOVERYSADLER, HEIDI D. 02 July 2004 (has links)
No description available.
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Bayesian estimation by sequential Monte Carlo sampling for nonlinear dynamic systemsChen, Wen-shiang 17 June 2004 (has links)
No description available.
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Foundations for a Network Model of Destination Value CreationStienmetz, Jason Lee January 2016 (has links)
Previous research has demonstrated that a network model of destination value creation (i.e. the Destination Value System model) based on the flows of travelers within a destination can be used to estimate and predict individual attractions’ marginal contributions to total visitor expenditures. While development to date of the Destination Value System (DVS) has focused on the value created from dyadic relationships within the destination network, previous research supports the proposition that system-level network structures significantly influence the total value created within a destination. This study, therefore, builds upon previous DVS research in order to determine the relationships between system-level network structures and total value creation within a destination. To answer this question econometric analysis of panel data covering 43 Florida destinations over the period from 2007 to 2015 was conducted. The panel data was created utilizing volunteered geographic information (VGI) obtained from 4.6 million photographs shared on Flickr. Results of econometric analysis indicate that both seasonal effects and DVS network structures have statistically significant relationships with total tourism-related sales within a destination. Specifically, network density, network out-degree centralization, and network global clustering coefficient are found to have negative and statistically significant effects on destination value creation, while network in-degree centralization, network betweenness centralization, and network subcommunity count are found to have positive and statistically significant effects. Quarterly seasonality is also found to have dynamic and statistically significant effects on total tourism-related sales within a destination. Based on the network structures of destinations and total tourism related sales within destinations, this study also uses k-means cluster analysis to classify tourism destinations into a taxonomy of six different system types (Exploration, Involvement, Development I, Development II, Consolidation, and Stars). This taxonomy of DVS types is found to correspond to Butler’s (1980) conceptualization of the destination life cycle, and additional data visualization and exploration based on the DVS taxonomy finds distinct characteristics in destination structure, dynamics, evolution, and performance that may be useful for benchmarking. Additionally, this study assesses the quality of VGI data for tourism related research by comparing DVS network structures based on Flickr data and visitor intercept survey data. Support for the use of VGI data is found, provided that thousands of observations are available for analysis. When fewer observations are available, aggregation techniques are recommended in order to improve the quality of overall destination network system quantification. This research makes important contributions to both the academic literature and the practical management of destinations by demonstrating that DVS network structures significantly influence the economic value created within the destination, and thus suggests that a strategic network management approach is needed for the governance of competitive destinations. As a result, this study provides a strong foundation for the DVS model and future research in the areas of destination resiliency, “smarter” destination management, and tourism experience design. / Tourism and Sport
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Uncertainty-aware dynamic reliability analysis framework for complex systemsKabir, Sohag, Yazdi, M., Aizpurua, J.I., Papadopoulos, Y. 18 October 2019 (has links)
Yes / Critical technological systems exhibit complex dynamic characteristics such as time-dependent
behavior, functional dependencies among events, sequencing and priority of causes that may alter the effects
of failure. Dynamic fault trees (DFTs) have been used in the past to model the failure logic of such systems,
but the quantitative analysis of DFTs has assumed the existence of precise failure data and statistical
independence among events, which are unrealistic assumptions. In this paper, we propose an improved
approach to reliability analysis of dynamic systems, allowing for uncertain failure data and statistical and
stochastic dependencies among events. In the proposed framework, DFTs are used for dynamic failure
modeling. Quantitative evaluation of DFTs is performed by converting them into generalized stochastic Petri
nets. When failure data are unavailable, expert judgment and fuzzy set theory are used to obtain reasonable
estimates. The approach is demonstrated on a simplified model of a cardiac assist system. / DEIS H2020 Project under Grant 732242.
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