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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.
81

Electric road vehicles for island communities : a study of the potential for introduction in the Scottish islands

Macpherson, Colin John January 1989 (has links)
The advent of high-performance, traffic-compatible, electric road vehicles (EVs) has brought with it an increasing range of uses and this study is concerned with evaluating the suitability of EVs for a hitherto unresearched application for this emerging technology, namely the island communities of Lewis and Harris. The stimulus for the renewed research and development of EVs has resulted largely from concerns about future energy supply, particularly of oil, and environmental conditions. An assessment of the state-of-the-art of EV technology and of traction battery systems in particular is presented. A strategy for development, commercialisation and diffusion is outlined which recognises the nature of the technology and its likely diffusion process. Market segments, such as island communities, which are suitable for early introduction must be identified. The islands of Scotland were chosen for investigation because of their current patterns of transport. The assessment of potential for EV introduction focuses on the requirements of a personal means of transport in terms of factors such as operating performance, utility, reliability, ability to refuel adequately, safety of operation and disposal, economic advantage and acceptability to motorists. Various relationships are established between the state of EV technology and the potential for introduction in the islands. A practical methodology for assessment which adopts a holistic approach is constructed. This is designed to be generally applicable to other similar EV assessments. The methodology employs a series of purpose-built computer simulation models and data collection techniques in order to model real life situations and systems as closely as possible, facilitating the evaluation of market potential and identification of barriers to EV introduction in the islands.
82

Stability of sodium electrodeposited from a series of room temperature chloroaluminate molten salts

Gray, Gary E. 05 1900 (has links)
No description available.
83

Optimization of the fuel consumption of a parallel hybrid electric vehicle

Khan, Bruno Shakou 05 1900 (has links)
No description available.
84

A design of a low-cost propulsion system for an electric scooter

Stevens, John Wesley 05 1900 (has links)
No description available.
85

Multidisciplinary Optimization of Hybrid Electric Vehicles: Component Sizing and Power Management Logic

Fan, Brian Su-Ming 15 June 2011 (has links)
A survey of the existing literature indicates that optimization on the power management logic of hybrid electric vehicle is mostly performed after the design of the powertrain architecture or the power source components are finalized. The goal of this research is to utilize Multidisciplinary Design Optimization (MDO) to automate and optimize the vehicle’s powertrain component sizes, while simultaneously determining the optimal power management logic in developing the most cost-effective system solution. A generic, modular, and flexible vehicle model utilizing a backward-looking architecture is created using scalable powertrain components. The objective of the research work is to study the energy efficiency of the vehicle system, where the dynamics of the vehicle is not of concern; a backward-looking architecture could be used to compute the power consumption and the overall efficiency accurately while minimizing the required computing resource. An optimization software platform utilizing multidisciplinary design optimization approach is implemented containing the generic vehicle model and an optimizer of the user’s choice. The software model is created in the MATLAB/Simulink environment, where the optimization code and the powertrain component properties are implemented using m-files, and the power consumption calculations of the vehicle system are performed in Simulink. Furthermore, a feature-based optimization technique is developed with the motivation of significantly reducing the simulation run-time. To demonstrate the capabilities of the developed approach and contributions of the research, two optimization case studies are undertaken: (i) series hybrid electric vehicles, and (ii) police vehicle anti-idling system. As the first case study, a plug-in battery-only series hybrid electric vehicle with similar power components as the Chevrolet Volt is created, where the battery size and the power management logic are simultaneously optimized. The objective function of the optimizer is defined from the financial cost perspective, where the objective is to minimize the initial cost of batteries, gasoline and electricity consumption over a period of five years, and the carbon tax as a penalty function for fuel emissions. The battery-only series hybrid electric vehicle is subsequently extended to include ultracapacitors, and the optimization process is expanded to the rest of the powertrain components and power management logic. A comparison between the optimization algorithms found that only genetic algorithm (GA) was capable of finding the optimal solution during a full simulation, while simulated annealing and pattern search were not able to converge to any solution after a 24-hour period. A comparison between the full genetic algorithm optimization and the feature-based (FB) method with secondary optimization found that although the final cost function of the FB methodology is higher than that of the full GA optimization, the total simulation run-time is approximately ten times less using the FB method. The behaviour of the solutions found via both methods exhibited almost identical characteristics, further confirming the validity of the feature-based methodology. Finally, a benchmarking comparison found that with more accurate manufacturers’ component data and additional appropriate performance requirements, the proposed software platform will be capable of predicting a solution that is comparable to the Chevrolet Volt. The second case study involves optimizing an anti-idling system for police vehicles using the same optimization algorithm and generic vehicle model. The goal of the optimization study is to select an additional battery and determine the power management logic to reduce the engine idling time of a police vehicle. It is found that depending on the SOC threshold, the duration of time over which the engine is activated varies in a non-linear fashion, where local minima and maxima exist. A design study confirmed that by utilizing the anti-idling system, significant cost reduction can be realized when compared to one without the anti-idling system. A comparison between the various optimization algorithms showed that the feature-based optimization can obtain a relatively accurate solution while reducing simulation time by approximately 90%. This significant reduction in simulation time warrants the feature-based optimization technique a powerful tool for vehicle design. Due to the high cost of the electrical energy storage components, it is currently still more cost-effective to use the fossil fuel as the primary energy source for transportation. However, given the rise of fuel cost and the advancement in the electrical energy storage technology, it is inevitable that the cost of the electrical and chemical energy storage method will reach a balance point. The proposed optimization platform allows the user the capability and flexibility to obtain the optimal vehicle solution with ease at any given time in the future.
86

Optimal Routing in Battery-Powered Vehicles

Faraj, Mahmoud S January 2013 (has links)
The increased interest in reducing greenhouse gas emissions has motivated renewed interest in electric vehicles technology as an alternative to current fossil-fuel based transportation equipment. Electric vehicles (EVs) are envisioned as a promising viable technology because of their friendly impact on the environment and higher efficiency over conventional vehicles that rely on fossil fuel. However, the EVs’ limited battery capacity, resulting in limited cruising range and long recharging time, hinders the widespread adoption of EVs. An essential requirement of EV motors is the ability to operate with minimum energy consumption in order to provide at least the same driving range as their Internal Combustion Engine (ICE) counterparts. Energy-optimal routing, which aims to find the least energy consuming routes, under battery constraints has been recognized as a viable approach to prolonging the cruising range of the EV battery. This thesis addresses the problem of optimal routing for EVs and proposes a solution to overcome the difficulties of optimal energy/time routing under battery constraints. A multi-criteria path-finding technique is proposed. The proposed technique functions in two modes and solves the problem of optimal energy/time routing in EVs with worst time complexity of . First, an energy mode to solve the problem of energy-optimal routing under battery constraints is introduced. This mode computes the most energy-efficient route from a source to a destination, thus extending the limited cruising range of a battery. Second, a time mode to solve the problem of optimal travel time routing under battery constraints, by computing the most efficient travel-time route from a source to a destination, is proposed. An EV can operate under these two modes to strike a balance between power consumption and travel time so as to satisfy user constraints and needs. In addition, a technique to reduce the effects of range anxiety on the vehicle operator is proposed. This technique computes a robust estimate of driving range. Furthermore, the technique analyzes an EV’s battery capacity required by the vehicle in order to reach a charging station. The thesis reports experimental work conducted to test and validate the proposed techniques under various driving conditions.
87

The ecological modernisation of industry : developing multi-disciplinary research in organization & environment.

Orssato, Renato J. January 2001 (has links)
This thesis develops suitable approaches to conduct environment-related research in organisations, as well as systematic means for understanding the emergent phenomenon of ecological modernisation in industrialised societies. The study is organised in two distinct parts: While Part I deals with environment-related theories and practices in (and around) modern organisations, Part II situates such theories and practices in an analysis of the context of the European automobile industry. The research problem is defined through several stages. The research questions driving Part I are premised on the exploratory nature of the study, developed in an unfolding interplay between the review of the literature, the collection of secondary and (exploratory) primary data, and the analysis and interpretation of the data. As the initial question is answered by reviewing the literature and interpreting the primary and secondary data, another question arises from the process, which then requires further research. Part II of the study departs from a proposition based on ecological modernisation theory, that pro-active environmental practices in corporations are part of a broader emergent sociological phenomenon, typical of modern industrialised societies. It analyses a specific socio-technical context that, hypothetically, is undergoing such process - that of the European automobile industry. Hence, the development of Part II aims at answering the following principal research question: Why is the European automobile industry undergoing ecological modernisation? Analytically, the concept of automobile field is proposed to establish a link between the product (automobile) and the context embedding its systems of production and consumption (field). The exploratory character of the study implied that the most adequate research procedures were of a qualitative nature. A combination of grounded theory and reflexive methodology is used to orientate the overall research process, which introduces a novel approach for the triangulation of qualitative data. Together, the chapters forming Part II of the thesis answer the principal research question. The fundamental technologies of the current technological regime of the automobile, as well as the economic and environmental implications of this regime are analysed. Then, an analysis of selected pilot programs to develop and commercialise electric vehicles, as well as schemes for the management of end-of-life vehicles in the Western European context is developed. Through the interplay between data collection and analysis, the thesis designs an analytical framework, built upon contingent factors, as well as circuits of political ecology, that foster or inhibit ecological modernisation in the automobile field. The study showed that the auto industry has developed incremental technological innovations and practices that resemble the pre-requisites for ecological modernisation. Radical innovations, however, are more likely to be initiated by outsiders. The concepts inherited from the past and reproduced in the present practice of car design explains such a situation as one that imposes a specific set of technologies on car manufacturing that require high levels of investment in systems of production. Such design paradigm not only imposes high break-even points for most car models; they also result in vehicles with extremely low environmental performance and entail serious limitations for increasing recycling rates of non-metallic parts. The characteristics of ecological modernisation in the European automobile industry are used to evaluate whether this phenomenon is conducive to sustainable industrial development. As an implication of this analysis, the concluding chapter presents suggestions for the enhancement of ecological modernisation theory. Fallibility is proposed as both a source of reflection about the appropriation of knowledge and a principle that can be used for the definition of eco-modernising strategies and actions. The acceptance of fallibility as an immanent characteristic of human action is critical for the approximation of the countervailing theories of ecological modernisation and risk society. Finally, if ecological modernisation is expected to facilitate sustainable industrial development, radical technological innovations may be necessary. Such radicalism in technology may need, however, an incremental institutional reform of modern societies. Together, radical technological innovations and incremental institutional reform constitute the concept of radical reformism, which is suggested for enhancement of the ecological modernisation theory, as well as for the development of its normative programmes.
88

The ecological modernisation of industry : developing multi-disciplinary research in organization & environment.

Orssato, Renato J. January 2001 (has links)
This thesis develops suitable approaches to conduct environment-related research in organisations, as well as systematic means for understanding the emergent phenomenon of ecological modernisation in industrialised societies. The study is organised in two distinct parts: While Part I deals with environment-related theories and practices in (and around) modern organisations, Part II situates such theories and practices in an analysis of the context of the European automobile industry. The research problem is defined through several stages. The research questions driving Part I are premised on the exploratory nature of the study, developed in an unfolding interplay between the review of the literature, the collection of secondary and (exploratory) primary data, and the analysis and interpretation of the data. As the initial question is answered by reviewing the literature and interpreting the primary and secondary data, another question arises from the process, which then requires further research. Part II of the study departs from a proposition based on ecological modernisation theory, that pro-active environmental practices in corporations are part of a broader emergent sociological phenomenon, typical of modern industrialised societies. It analyses a specific socio-technical context that, hypothetically, is undergoing such process - that of the European automobile industry. Hence, the development of Part II aims at answering the following principal research question: Why is the European automobile industry undergoing ecological modernisation? Analytically, the concept of automobile field is proposed to establish a link between the product (automobile) and the context embedding its systems of production and consumption (field). The exploratory character of the study implied that the most adequate research procedures were of a qualitative nature. A combination of grounded theory and reflexive methodology is used to orientate the overall research process, which introduces a novel approach for the triangulation of qualitative data. Together, the chapters forming Part II of the thesis answer the principal research question. The fundamental technologies of the current technological regime of the automobile, as well as the economic and environmental implications of this regime are analysed. Then, an analysis of selected pilot programs to develop and commercialise electric vehicles, as well as schemes for the management of end-of-life vehicles in the Western European context is developed. Through the interplay between data collection and analysis, the thesis designs an analytical framework, built upon contingent factors, as well as circuits of political ecology, that foster or inhibit ecological modernisation in the automobile field. The study showed that the auto industry has developed incremental technological innovations and practices that resemble the pre-requisites for ecological modernisation. Radical innovations, however, are more likely to be initiated by outsiders. The concepts inherited from the past and reproduced in the present practice of car design explains such a situation as one that imposes a specific set of technologies on car manufacturing that require high levels of investment in systems of production. Such design paradigm not only imposes high break-even points for most car models; they also result in vehicles with extremely low environmental performance and entail serious limitations for increasing recycling rates of non-metallic parts. The characteristics of ecological modernisation in the European automobile industry are used to evaluate whether this phenomenon is conducive to sustainable industrial development. As an implication of this analysis, the concluding chapter presents suggestions for the enhancement of ecological modernisation theory. Fallibility is proposed as both a source of reflection about the appropriation of knowledge and a principle that can be used for the definition of eco-modernising strategies and actions. The acceptance of fallibility as an immanent characteristic of human action is critical for the approximation of the countervailing theories of ecological modernisation and risk society. Finally, if ecological modernisation is expected to facilitate sustainable industrial development, radical technological innovations may be necessary. Such radicalism in technology may need, however, an incremental institutional reform of modern societies. Together, radical technological innovations and incremental institutional reform constitute the concept of radical reformism, which is suggested for enhancement of the ecological modernisation theory, as well as for the development of its normative programmes.
89

Dynamics and energy management of electric vehicles /

Van Schalkwyk, Daniel Jacobus. January 2007 (has links)
Thesis (MScIng)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.
90

Simulation and analysis of the control system of the hybrid vehicle

Wu, Tahchang Jimmy. January 1989 (has links)
Thesis (M.S.)--Ohio University, June, 1989. / Title from PDF t.p.

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