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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Evaluation and Improvement of a 2D UML Class Diagram Layout Algorithm

Schrepfer, Matthias January 2009 (has links)
<p> </p><p>Measuring the quality of software is a complex task. Various analyses and computations of software quality metrics support this process. For certain investigations it is helpful to visualize the relations between different components of software in order to check quality aspects. The VizzAnalyzer tool was developed for these purposes and allows the visualization of software systems as UML2.0 class diagrams. The visualization plug-in lays out the internal structure and ensures a high readability of the layouts.</p><p>In this thesis the layout algorithm embedded in the plug-in is optimized to increase its performance and the readability of layouts computed. The interaction with other applications is an important aspect. The current visualization plug-in is extended to meet the requirements of the Quick Orientation Viewer and to support future applications. The optimizations and extensions are further addressed to enhance the usability and the functions provided by the layout algorithm.</p><p> </p>
192

Multi-objective Optimization of Plug-in Hybrid Electric Vehicle (PHEV) Powertrain Families considering Variable Drive Cycles and User Types over the Vehicle Lifecycle

Al Hanif, S. Ehtesham 02 October 2015 (has links)
Plug-in Hybrid Electric vehicle (PHEV) technology has the potential to reduce operational costs, greenhouse gas (GHG) emissions, and gasoline consumption in the transportation market. However, the net benefits of using a PHEV depend critically on several aspects, such as individual travel patterns, vehicle powertrain design and battery technology. To examine these effects, a multi-objective optimization model was developed integrating vehicle physics simulations through a Matlab/Simulink model, battery durability, and Canadian driving survey data. Moreover, all the drivetrains are controlled implicitly by the ADVISOR powertrain simulation and analysis tool. The simulated model identifies Pareto optimal vehicle powertrain configurations using a multi-objective Pareto front pursuing genetic algorithm by varying combinations of powertrain components and allocation of vehicles to consumers for the least operational cost, and powertrain cost under various driving assumptions. A sensitivity analysis over the foremost cost parameters is included in determining the robustness of the optimized solution of the simulated model in the presence of uncertainty. Here, a comparative study is also established between conventional and hybrid electric vehicles (HEVs) to PHEVs with equivalent optimized solutions, size and performance (similar to Toyota Prius) under both the urban and highway driving environments. In addition, breakeven point analysis is carried out that indicates PHEV lifecycle cost must fall within a few percent of CVs or HEVs to become both the environmentally friendly and cost-effective transportation solutions. Finally, PHEV classes (a platform with multiple powertrain architectures) are optimized taking into account consumer diversity over various classes of light-duty vehicle to investigate consumer-appropriate architectures and manufacturer opportunities for vehicle fleet development utilizing simplified techno-financial analysis. / Graduate / 0540 / 0548 / ehtesham@uvic.ca
193

Energy and environmental contexts of cities, transportation systems, and emerging vehicle technologies : how plug-in electric vehicles and urban design influence energy consumption and emissions

Nichols, Brice G. 19 March 2014 (has links)
This thesis is divided into two parts. The first evaluates the role of the built environment in life-cycle energy consumption, by comparing different neighborhood and city styles. Through a holistic modeling and accounting framework, this work identifies the largest energy-consuming sectors, among residential and commercial buildings, personal vehicles and transit trips, and supporting infrastructure (roads, sidewalks, parking lots, water pipes, street lighting). Life-cycle energy calculations include operational energy use (e.g., gasoline for vehicles, electricity and natural gas for buildings) and embodied energy used to produce materials and construct buildings and infrastructure. Case study neighborhoods in Austin, Texas, and larger-scale regional models suggest that building energy demands comprise around 50% of life-cycle energy demands, while transportation demands (from driving and infrastructure alike) contribute around 40%, across all cases. However, results also suggest that population density and average residential unit size play a major role in defining per-capita energy consumption. Operational demands made up about 90% of life-cycle energy demands, suggesting that v most urban energy savings can be obtained from reduced personal vehicle trips and more efficient vehicles and buildings. Case study comparisons suggest that neighborhoods and regions with greater density and higher share of multi-family housing units tend to reduce operational (and thus life-cycle) energy demands with less travel demand and decreased home and work energy use, per capita. The second part of this modeled plug-in electric vehicle (PEV) emissions impacts in Texas, by considering four possible vehicle adoption scenarios (where PEVs make up 1, 5, 10, and 25% of total passenger vehicles). The analysis anticipates PEV electricity demand and emissions rates, based on current Texas power grid data. Results indicate that PEV emissions depend significantly on which specific power plants are used to power the vehicles, but that PEVs' average per-mile emissions rates for NO[subscript x], PM, and CO₂ are all likely to be lower than today's average passenger car, when today's average mix is used. Power produced from 100% coal plants could produce 14 times as much NO[subscript x], 3,200 times as much SO₂, nearly 10 times as much CO₂ and CO₂eq, 2.5 times as much PM₁₀, and VOCs, and nearly 80 times the NO₂ compared to a grid with 100% natural gas plants. / text
194

Development and Implementation of Control System for an Advanced Multi-Regime Series-Parallel Plug-in Hybrid Electric Vehicle

Prescott, Daniel 28 August 2015 (has links)
Following the Model-Based-Design (MBD) development process used presently by the automotive industry, the control systems for a new Series-Parallel Multiple-Regime Plug-in Hybrid Electric Vehicle (PHEV), UVic EcoCAR2, have been developed, implemented and tested. Concurrent simulation platforms were used to achieve different developmental goals, with a simplified system power loss model serving as the low-overhead control strategy optimization platform, and a high fidelity Software-in-Loop (SIL) model serving as the vehicle control development and testing platform. These two platforms were used to develop a strategy-independent controls development tool which will allow deployment of new strategies for the vehicle irrespective of energy management strategy particulars. A rule-based energy management strategy was applied and calibrated using genetic algorithm (GA) optimization. The concurrent modeling approach was validated by comparing the vehicle equivalent fuel consumption between the simplified and SIL models. An equivalency factor (EF) of 1 was used in accounting for battery state of charge (SOC) discrepancies at cycle end. A recursively-defined subsystem efficiency-based EF was also applied to try to capture real-world equivalency impacts. Aggregate results between the two test platforms showed translation of the optimization benefits though absolute results varied for some cycles. Accuracy improvements to the simplified model to better capture dynamic effects are recommended to improve the utility of the newly introduced vehicle control system development method. Additional future work in redefining operation modes and mode transition threshold conditions to approximate optimal vehicle operation is recommended and readily supported by the control system platform developed. / Graduate / 0540 / 0548 / 0790 / d.e.prescott@gmail.com
195

Sustainable green infrastructure and operations planning for plug-in hybrid vehicles (PHEVs) : a Tabu Search approach

Dashora, Yogesh 27 January 2011 (has links)
Increasing debates over a gasoline independent future and the reduction of greenhouse gas (GHG) emissions has led to a surge in plug-in hybrid electric vehicles (PHEVs) being developed around the world. Due to the limited all-electric range of PHEVs, a daytime PHEV charging infrastructure will be required for most PHEVs’ daily usage. This dissertation, for the first time, presents a mixed integer mathematical programming model to solve the PHEV charging infrastructure planning (PCIP) problem. Our case study, based on the Oak Ridge National Laboratory (ORNL) campus, produced encouraging results, indicates the viability of the modeling approach and substantiates the importance of considering both employee convenience and appropriate grid connections in the PCIP problem. Unfortunately, the classical optimization methods do not scale up well to larger practical problems. In order to effectively and efficiently attack larger PCIP problems, we develop a new MASTS based TS algorithm, PCIP-TS to solve the PCIP. The results from computational experiments for the ORNL campus problem establish the dominant supremacy of the PCIP-TS method both in terms of solution quality and computational time. Additional experiments with simulated data representative of a problem that might be faced by a small city show that PCIP-TS outperforms CPLEX based optimization. Once the charging infrastructure is in place, the immediate problem is to judiciously manage this system on a daily basis. This thesis formally develops a mixed integer linear program to solve the daily the energy management problem (DEM) faced by an organization and presented results of a case study performed for ORNL campus. The results from our case study, based on the Oak Ridge National Laboratory (ORNL) campus, are encouraging and substantiate the importance of controlled PHEV fleet charging and realizing V2G capabilities as opposed to uncontrolled charging methods. Although optimal solutions are obtained, the solver requires practically unacceptable computational times for larger problems. Hence, we develop a new MASTS based TS algorithm, DEM-TS, for the DEM models. Results for ORNL campus data set prove the dominant computational efficiency of the DEM-TS. For the simulated extended sized problems that resemble the complexity of a problem faced by a small city, the results prove that DEM-T not only achieves optimality, but also produces sets of multiple alternate optimal solutions. These could be very helpful in practical settings when alternate solutions are necessary because some solutions may not be deployable due to unforeseen circumstances. / text
196

Analyzing the Performance of Lithium-Ion Batteries for Plug-In Hybrid Electric Vehicles and Second-Life Applications

January 2017 (has links)
abstract: The automotive industry is committed to moving towards sustainable modes of transportation through electrified vehicles to improve the fuel economy with a reduced carbon footprint. In this context, battery-operated hybrid, plug-in hybrid and all-electric vehicles (EVs) are becoming commercially viable throughout the world. Lithium-ion (Li-ion) batteries with various active materials, electrolytes, and separators are currently being used for electric vehicle applications. Specifically, lithium-ion batteries with Lithium Iron Phosphate (LiFePO4 - LFP) and Lithium Nickel Manganese Cobalt Oxide (Li(NiMnCo)O2 - NMC) cathodes are being studied mainly due to higher cycle life and higher energy density values, respectively. In the present work, 26650 Li-ion batteries with LFP and NMC cathodes were evaluated for Plug-in Hybrid Electric Vehicle (PHEV) applications, using the Federal Urban Driving Schedule (FUDS) to discharge the batteries with 20 A current in simulated Arizona, USA weather conditions (50 ⁰C & <10% RH). In addition, 18650 lithium-ion batteries (LFP cathode material) were evaluated under PHEV mode with 30 A current to accelerate the ageing process, and to monitor the capacity values and material degradation. To offset the high initial cost of the batteries used in electric vehicles, second-use of these retired batteries is gaining importance, and the possibility of second-life use of these tested batteries was also examined under constant current charge/discharge cycling at 50 ⁰C. The capacity degradation rate under the PHEV test protocol for batteries with NMC-based cathode (16% over 800 cycles) was twice the degradation compared to batteries with LFP-based cathode (8% over 800 cycles), reiterating the fact that batteries with LFP cathodes have a higher cycle life compared to other lithium battery chemistries. Also, the high frequency resistance measured by electrochemical impedance spectroscopy (EIS) was found to increase significantly with cycling, leading to power fading for both the NMC- as well as LFP-based batteries. The active materials analyzed using X-ray diffraction (XRD) showed no significant phase change in the materials after 800 PHEV cycles. For second-life tests, these batteries were subjected to a constant charge-discharge cycling procedure to analyze the capacity degradation and materials characteristics. / Dissertation/Thesis / Masters Thesis Materials Science and Engineering 2017
197

Framework para interface e gerenciamento de bancos de dados / Interface and management framework for systems data bank

Silva, Lidiana Mendes da 23 December 2009 (has links)
The usage of specific databases for certain application does not allow the replacement of database or sharing information with other databases by user, without rebuilding the entire application, turning non-trivial the application of the solutions proposed in the literature. This reduces the interoperability among different suppliers of present biomedical data. This paper describes the design and development of a system for interface and management of biomedical signals databases. The system s features includes the use of different databases and the storage of the data for further analysis and was designed using the object-oriented technique, plug-ins and reflection technique, leading to create an application capable of connecting with the different databases. The developed system has capability of storage biomedical information, through the use of adaptive systems and plug-ins, reducing the problems of lack of compatibility between data banks, difficulties in maintenance and integration among them. The experiment results showed that the framework is able to collect patients biomedical data, that may be registered with their clinical features, and interact with differentdatabases. / A utilização de bancos de dados específicos para determinado aplicativo não permite ao usuário a substituição do banco de dados ou o compartilhamento com outras bases de informações sem a reconstrução de todo o aplicativo, tornando não trivial a aplicação das soluções propostas na literatura. Isso reduz a interoperabilidade entre os aplicativos de software de diferentes fornecedores de equipamentos biomédicos existentes. Este trabalho descreve o projeto e o desenvolvimento de um framework para interface e gerenciamento de bancos de dados utilizados em aplicações biomédicas. O sistema se caracteriza por permitir que diferentes bancos de dados possam ser utilizados para diferentes aplicativos a fim de armazenar os dados para posteriores análises. O sistema foi projetado utilizando a técnica de orientação a objetos, plug-ins e reflexão, permitindo criar aplicativos capazes de conectarem-se com os diferentes bancos de dados. Os resultados demonstram que o framework permite a coleta e o armazenamento de informações biomédicas por meio de sistemas adaptativos e de plug-ins, minimizando os problemas de falta de compatibilidade entre bancos, as dificuldades de manutenção e melhorando a integração dos mesmos. / Mestre em Ciências
198

Desenvolvimento de um aplicativo computacional para dimensionamento técnico e econômico de biodigestores tipo tubular / Development of an computacional application for technical and economical sizing of tubular type biodigesters

Alves , Anelisiane Maria 23 March 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2017-09-04T19:21:36Z No. of bitstreams: 2 Anelisiane Maria Alves.pdf: 2439673 bytes, checksum: fd370a11122ff19c0d83073490e93fb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-04T19:21:36Z (GMT). No. of bitstreams: 2 Anelisiane Maria Alves.pdf: 2439673 bytes, checksum: fd370a11122ff19c0d83073490e93fb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-23 / Technological and economic development occurred through the extraction of the environment and industrialization in a globalized model of society. This model is now fully dependent on sources of energy to continue to function. However, due to the environmental politicization and the problematization of the use of fossil sources, the search for an alternative energy model has been the subject of academic research and public policies for some years. The present work focuses on the development of a computational program that will provide the user, often unaware of the research in development, with the access and the necessary guidance for the implantation of a tubular rural biodigester. The application was developed in Java language, where the technical and economical sizing methodology used takes into account data such as the type and number of animals and the user's monthly electricity consumption. After the program processes the calculation routine, the user is presented the results in 3 different screens, one containing a generic image with the nomenclature adopted for the estimated dimensions, a screen with technical information of the design and a final screen with information of economic projection. This work is expected to disseminate and democratize alternative research and technologies through the use of digital technology. / O desenvolvimento tecnológico e econômico ocorreu através do extrativismo do meio ambiente e da industrialização em um modelo globalizado de sociedade. Esse modelo encontra-se hoje plenamente depende de fontes de energias para continuar funcionando. Entretanto, em decorrência da politização ambiental e da problematização quanto ao uso de fontes fósseis, a busca por um modelo energético alternativo tem sido tema de pesquisas acadêmicas e políticas públicas há alguns anos. O presente trabalho tem como foco o desenvolvimento de um programa computacional o qual proporcionará ao usuário, muitas vezes alheio às pesquisas em desenvolvimento, o acesso e o direcionamento necessários para a implantação de um biodigestor rural tubular, devendo ser informados apenas alguns dados bases. O aplicativo foi desenvolvido em linguagem Java, onde a metodologia de dimensionamento técnico e econômico utilizada levam em conta dados como o tipo e número de animais e o consumo mensal de energia elétrica do usuário. Após o programa processar a rotina de cálculos, é apresentado ao usuário os resultados em 3 telas diferentes, uma contendo uma imagem genérica com a nomenclatura adotada para as dimensões estimadas, uma tela com informações técnicas do dimensionamento e uma tela final com informações de projeção econômica. Espera-se com esse trabalho a difusão e a democratização de pesquisas e tecnologias alternativas através do uso da tecnologia digital.
199

Walk-A-Way : A Maya Plug-in for Walk Cycle Automation

Christiansson, Kajsa January 2009 (has links)
In 3D and 2D animations walk cycles of characters appear very frequently and are an important way of expressing various aspects of the story told. However walk cycles are tedious and time consuming to animate. In this work an Autodesk MAYA plug-in has been developed, that aims at automating this process. The walk cycle plug-in can be highly beneficial for animators when creating convincing walk cycles in a fast and simple way. The plug-in calculates the right values for each phase in the walk cycle. The GUI of the plug-in makes it easy to provide the required input parameters. In addition, the plug-in allows the animation of a character to walk along a chosen path.
200

Contribution of Vehicle-to-Grid (V2G) to the energy management of the Electric Vehicles fleet on the distribution network / Contribution du Vehicle-to-Grid (V2G) à la gestion énergétique d’un parc de Véhicules Électriques sur le réseau de distribution

Sarabi, Siyamak 29 November 2016 (has links)
L'augmentation des densités de puissance et d'énergie des SSE (système de stockage électrique) des véhicules électriques/véhicules hybrides rechargeable (VEs/VHRs), tout en conservant des coûts raisonnables pour l'utilisateur, et le développement de convertisseurs d'énergie électrique à haute densité de puissance volumique, et de plus en plus performant vont favoriser la production en masse de véhicules électrifiés. Une partie de ces véhicules électriques (VEs/VHRs) nécessitent une connexion au réseau pour la recharge des batteries. L’insertion de ces nouvelles charges dans le réseau présentera alors plusieurs enjeux et impacts significatifs pour les réseaux électriques puisqu’ils doivent répondre localement à des demandes de puissance non négligeables. Ce projet de thèse vise à étudier et réduire les impacts des VEs/VHRs sur les réseaux de distribution grâce à la technologie Vehicle-to-Grid (V2G). Le véhicule électrique alimente le réseau en fonction des besoins du système électrique (modèle bidirectionnel) et lui offre un service de flexibilité. Ces travaux de recherche ont pour but d'approfondir les concepts dans lequel l’alimentation des véhicules électriques (VE) et/ou hybrides de type P-VEH est intégrée à la gestion du réseau de distribution et des « hubs énergétiques » du futur. L’objectif de la thèse est d’abord étudier les service systèmes possible à fournir grâce à V2G, ensuite de concevoir un système de supervision qui assurera une gestion énergétique de ces nouvelles charges en choisissant le mode de recharge et/ou décharge adéquat et en prenant également en considération la demande de consommation locale et la présence de production de type renouvelable (photovoltaïque, éolien) dans le réseau de distribution. Cette supervision se fera dans un premier temps « en hors ligne » et par la suite « en ligne ». On aura recours à l’utilisation de méthodes d’intelligence artificielle comme l’apprentissage automatique (Machine Learning) et la logique floue, la commande prédictive ainsi que des méthodes d’optimisation hybrides (stochastiques et déterministes). / The power and energy density increment of the electrical storage system (ESS) of electric vehicles/Plug-in hybrid electric vehicles (EVs/PHEVs), while maintaining reasonable costs for the user, and the development of converters of electrical energy to high power density and more and more powerful, will encourage the mass production of electrified vehicles. Beyond, electric vehicles (EVs/PHEVs) require a connection to the grid for the charging of the batteries. The insertion of these new loads in the grid will then present several issues and significant impacts for electrical networks since they must respond locally to non-negligible power requests. This PhD thesis aims to study and reduce the impacts of the EVs/PHEVs on the distribution grid thanks to the vehicle-to-Grid (V2G) technology. The electric vehicle supplies the grid depending on the needs of the electrical system (bi-directional model) and offers a flexible service. These works of research have aimed to deepen the concepts in which the supply of electric vehicles (EV) and/or hybrids of type PHEV is integrated with the management of the distribution network and the future "energy hubs". The objective of the thesis is at first to examine the possible ancillary services provided by V2G, then to design a system of supervision which will ensure an energy management of these new loads by choosing the adequate mode of charge/discharge and also taking into consideration the request of local consumption and the presence of renewable production of type photovoltaic and wind in the distribution grid. This supervision will be in a first step "offline" and subsequently "online". The methods which are used in this thesis are as follows; artificial intelligence such as machine learning and fuzzy logic, the predictive control as well as the methods of hybrids optimization (stochastic and deterministic).

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