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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.
121

The water-energy nexus : a comprehensive analysis in the context of New South Wales.

Marsh, Debborah January 2008 (has links)
Water and electricity are fundamentally linked. Policy reforms in both industries, however, do not appear to acknowledge the links nor consider their wider implications. This is clearly unhelpful, particularly as policy makers attempt to develop effective responses to water and energy issues, underpinned by prevailing drought conditions and impending climate change. Against this backdrop, this research has comprehensively analysed the links between water and electricity – termed water-energy nexus – in the context of New South Wales. For this purpose, this research has developed an integrated methodological framework. The philosophical guidance for the development of this framework is provided by Integral Theory, and its analytical foundations rest on a suite of research methods including historical analysis, inputoutput analysis, analysis of price elasticities, and long-term scenario analysis. This research suggests that the historical and inextricable links between water and electricity, in the absence of integrated policies, has given rise to water-energy trade-offs. In the electricity industry, water-intensive coal-fired power stations that dominate base-load capacity in the National Electricity Market has resulted in intra- and inter-jurisdictional water sharing tradeoffs. Intermediate and peak demand technologies, suchas gas-fired, cogeneration and renewables, however, would significantly reduce the industry’s water consumption and carbon emissions. Drought and climate change adaptation responses in the water industry are likely to further increase electricity demand andpotentially contribute to climate change, due to policies that encourage investment in energy-intensive technologies, such as desalination, advanced wastewater treatment and rainwater tanks. Increasing electricity costs due to water shortages and the introduction of emissions trading will futher increase water and electricity prices for end users. Demand management strategies in both industries will assist in curbing price increases, however, their effectiveness is lessened by investment in water- and energy-intensive technologies in both industries. The analysis also demonstrates that strategies to reduce water and electricity consumption of ‘other’ production sectors in New South Wales is overwhelmingly dependent on how deeply a particular sector is embedded in the economy, in terms of its contribution to economic output, income generation and employment growth. Regulation, demand management programs, and water pricing policies, for example, that reduce the water and energy intensity of agriculture and key manufacturing sectors are likely to benefit the wider economy and the Environment. The future implications of the water-energy nexus are examined through long-term scenario analysis for New South Wales for 2031. The analysis demonstrates how policy decisions shape the domain for making philosophical choices by society - in terms of the balance between relying on alternative technologies and market arrangements, with differing implications for water and electricity use, and for instigating behavioural change. Based on these findings, this research puts forward a range of recommendations, essentially arguing for reorienting existing institutional arrangements, government measures and industry activities in a way that would encourage integration between the water and energy policies. Although the context of this research is New South Wales, the findings are equally relevant for other Australian states, which share the same national water and energy policy frameworks. Further, the concepts and frameworks developed in this research are also of value to other countries and regions that are faced with the task of designing appropriate policy responses to redress their water and energy challenges.
122

Residential sector deregulation in the electricity industry : analysis of electricity consumption patterns /

Gupta, Pavan. January 2004 (has links)
Thesis (Ph.D.) -- University of Western Sydney, 2004. / "A thesis presented to the University of Western Sydney, in partial fulfilment of the requirements of the degree of Doctor of Philosophy" Bibliography : leaves 273-285.
123

Analysing electricity markets with evolutionary computation /

Nguyen, Duy Huu Manh. January 2002 (has links)
Thesis (Ph.D.)--University of Western Australia, 2003.
124

Monopoly bidding strategy under the Ontario MPMA and system reliability /

He, Aiming. January 1900 (has links)
Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 180-182). Also available in electronic format on the Internet.
125

Characterizing dynamic power and data rate policies for WirelessUSB networks /

Barlow, Jeffrey L., January 2006 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Computer Science, 2006. / Includes bibliographical references (p. 127-129).
126

A state-based method to model and analyze the power consumption of embedded systems

Haulin, Lars January 2018 (has links)
In this work I have evaluated a method to model, measure and analyze the power consumption of embedded systems. The method combines current measurement with debug trace data telling which parts of the systems that are enabled. This makes it possible to compute the individual current consumption of the parts in the system from a single measurement point. The method allows an embedded systems engineer to determine the power consumption of individual parts in a system to either get an overview or to compare several revisions of hardware and/or software with each other. The method also captures the system dynamics of the power delivery route. This makes the model consumption behave more like the actual system around state transitions. The case study is focused on the Arm-based microcontroller CC2650 from Texas Instruments and uses the I-scope/I-jet probe from IAR Systems to measure current consumption and collect trace data.
127

Comparison of Performance and Power Consumption Between GPS and Sigfox Positioning Using Pycom Modules

Zhou, Xujia, Flora, Eduardo January 2018 (has links)
Sigfox is one of the newly-emerging LPWAN (Low Power Wide Area Network) technologies aiming to provide power-efficient solutions to the world of IoT. This study presents a comparison between Sigfox Geolocation and GPS (Global Positioning System) in terms of power consumption and performance which includes three metrics: accuracy and precision, response rate and response time. This study includes for the first part a series of lab tests where Sigfox Geolocation and GPS were studied in a single Sleep, Wake up, Idle, Tx/Rx cycle. For the second part, field tests with different geographical parameters (altitude, population, mobility) were conducted. Results of lab tests show that power consumption difference between Sigfox and GPS is a linear function of Idle time. In field tests, GPS presents a far superior performance than Sigfox in all metrics and marginally better power efficiency for relatively short Idle interval. For both GPS and Sigfox, a correlation between power efficiency and performance was observed. Results show that GPS operates best in rural environments while Sigfox stands out in urban ones. Payload size was observed to affect Sigfox in both power consumption and performance while different transmission rates only affect power consumption but do not seem to impact the other metrics. A solution based on the outcome of this study is suggested for a freight-monitoring system where geolocation is handled by GPS and the coordinates transmitted via Sigfox. As an emerging technology under constant development, Sigfox Geolocation is expected to have improved performance in the near future.
128

Optimization of user association and resource allocation in heteregeneous networks / Optimisation de l'association des utilisateurs et de l'allocation des ressources dans les réseaux sans fil hétérogènes

Zalghout, Mohamad 23 October 2017 (has links)
Aujourd'hui, l'extension des exigences du trafic de données sans fil dépasse le taux de croissance de la capacité des nouvelles technologies d'accès sans fil. Par conséquent, les réseaux sans fil mobiles de la future génération proposent des architectures hétérogènes, généralement appelées réseaux sans fil hétérogènes (HWN). HWN se caractérisent par l'intégration des réseaux cellulaires et des réseaux locaux sans fil (WLAN) pour répondre aux besoins des utilisateurs et améliorer la capacité du système. En fait, l'intégration de différents types de technologies d'accès sans fil dans HWN offre des choix flexibles pour que les utilisateurs soient associés au réseau qui répond le mieux à leurs besoins. Dans ce contexte, cette thèse traite le problème d'association d'utilisateurs et le problème d'allocation de ressources dans un système sans fil hétérogène basé sur des points d'accès Wi-Fi intégrés et des stations de base L TE. Les contributions de cette thèse pourraient être divisées en trois parties principales. Dans la première partie, un nouveau problème d'association d'utilisateurs et d'optimisation de l'allocation des ressources est formulé pour maximiser la satisfaction globale des utilisateurs dans le système. La satisfaction de l'utilisateur est basée sur une fonction de profit pondérée qui vise à améliorer la puissance relative du signal reçu et la diminution de la consommation d'énergie des terminaux mobiles (MT). Étant donné qu'un MT n'est autorisé à être associé qu'à un seul réseau à la fois, le problème d'optimisation formulé est binaire avec une complexité NP complète. Ensuite, plusieurs solutions centralisées avec une complexité à temps polynomial sont proposées pour résoudre le problème formulé. Les solutions proposées sont basées sur des approches heuristiques et sur la relaxation continue du problème d'optimisation binaire formulé. La deuxième partie de la thèse vise à fournir une solution distribuée pour le problème formulé. La solution distribuée proposée déploie la technique de détente lagrangienne pour convertir le problème global formulé en plusieurs problèmes de Knapsack distribués, chaque réseau traite son problème Knapsack correspondant. La méthode de sous gradient est utilisée pour trouver les multiplicateurs lagrangiens optimaux ou sous optimaux. Enfin, la troisième partie de la thèse étudie de nouvelles perspectives de la formulation du problème d'optimisation et ses solutions centralisées et distribuées correspondantes. Un problème d'association d'utilisateurs et d'allocation de ressources basé sur la priorité est formulé. Le problème est ensuite réduit en plusieurs problèmes résolus à l'aide des solutions proposées réparties et centralisées. En outre, une nouvelle solution de maximisation de l'efficacité énergétique est proposée en modifiant les objectifs du problème d'optimisation originalement formulé. / It is indicated that the expansion of the wireless data traffic requirements exceeds the capacity growth rate of new wireless access technologies. Therefore, next-generation mobile wireless networks are moving toward heterogeneous architectures usually referred to as heterogeneous wireless networks (HWNs). HWNs are usually characterized by the integration of cellular networks and wireless local area networks (WLANs) to meet user requirements and enhance system capacity. In fact, integrating different types of wireless access technologies in HWNs provides flexible choices for users to be associated with the network that best satisfies their needs. In this context, this thesis discusses the user association and downlink resource allocation problem in a heterogeneous wireless system that is based on integrated Wi-Fi access points (APs) and long-term evolution (L TE) base stations (BSs). The contributions of this thesis could be divided into three main parts. In the first part, a novel user association and resource allocation optimization problem is formulated to maximize the overall user satisfaction in the system. The user satisfaction is based on a weighted profit function that aims at enhancing the relative received signal strength and decreasing the power consumption of mobile terminals (MTs). Since a MT is only allowed to be associated with a single network at a time, the formulated optimization problem is binary with an NP-complete complexity. Then, multiple centralized solutions with polynomial-time complexities are proposed to solve the formulated problem. The proposed centralized solutions are based on heuristic approaches and on the continuous re laxation of the formulated binary optimization problem. The second part of the thesis aims at providing a distributed solution for the formulated problem. The proposed distributed solution deploys the Lagrangian relaxation .technique in order to convert the global formulated problem into multiple distributed Knapsack problems each network processes its corresponding Knapsack problem. The sub-gradient method is used in order to find the optimal, or near optimal, Lagrangian multipliers. Finally, the third part of the thesis studies new perspectives of the formulated optimization problem and its corresponding centralized and distributed solutions. Mainly, a generalized priority-aware user association and resource allocation problem is formulated. The priority-aware problem is then reduced into multiple problems that are solved using the proposed centralized and distributed solutions. Moreover, a novel power efficiency maximization solution is proposed by altering the objectives of the main formulated optimization problem.
129

A socio-technical inquiry into semiotics and ethnology in South Africa, with special reference to electricity

Qually, Byron Alexander January 2010 (has links)
Thesis (MTech (Industrial Design))--Cape Peninsula University of Technology, 2009 / Demand Side Management (DSM) within a South African context requires a transdisciplinary approach to comprehend electricity consumption. Current research suggests a technical determinism, whereby design teams fail to acknowledged social factors and cultural influences when conceptualising DSM artefacts. The result of which, is that artefacts fail to be adopted by the market, and consumer behaviour and electricity consumption remains unchanged. The thesis aims to demonstrate the hypothesis, that semiotics and ethnology may affect sustainable residential electricity management in South Africa. The ubiquitous literature on electricity management is administered by means of the theoretical lens, Sociotechnical Theory. Mixed method instrument obtain fieldwork data from three of the eleven official South African languages: Afrikaans, English and IsiXhosa.
130

Eficiência energética em indústria frigorífica: desafios de implantação

Frozza, Janquiel Fernando 28 August 2013 (has links)
Esta pesquisa tem por objetivo efetuar uma investigação acerca da eficiência energética nas indústrias, com foco na identificação dos potenciais de conservação de energia e possíveis barreiras para se implantar um sistema de gestão de energia, tendo como principais motivações o lançamento do Plano Nacional de Eficiência Energética (PNEf), que prevê uma grande economia de energia para os próximos anos, e da norma ABNT NBR ISO 50001- Sistema de gestão de energia. Num primeiro instante, fez-se um estudo dos principais métodos de gestão e eficiência energética que estão sendo empregados nas indústrias. Após o desenvolvimento de estudos preliminares, realizou-se uma auditoria energética em um frigorífico de abate de aves situado na região Sudoeste do Paraná. Nesta auditoria foram estabelecidos os centros de maior consumo, as linhas de base dos principais insumos energéticos e potenciais de conservação de energia dos principais módulos temáticos. Verificou-se que o sistema de refrigeração representa aproximadamente 81% do consumo de energia elétrica da planta e que do total de 11 módulos temáticos existentes, três deles representam aproximadamente 97% do consumo de energia elétrica da planta, sendo motores, sistema de refrigeração e sistema de ar comprimido. Constatou-se também, com uma análise econômica de perdas, que há potenciais de conservação de energia, principalmente em motores. Por fim, identificaram-se as principais barreiras para se implantar um sistema de gestão de energia em uma planta, principalmente no que se refere à elaboração de linhas de base e indicadores de desempenho energético. Tais barreiras demonstram uma falsa expectativa do PNEf para alcançar as atuais metas se não houver maior impacto dos progressos induzidos (por políticas públicas). / This research has an objective to investigate the electrical power efficiency in industries, aiming to identify potential energy saving and possible barriers to deploy an energy management system, having as one of its priorities the main motivations to the release of a National Plan of Electrical Efficiency (NPEE), in which forecast a great power saving for the following years and the norm ABNT NBR ISO 50001-Energy management system. At a first moment, a study was made about the main methods of electrical efficiency management, in which are being introduced in industries. After the development of preliminary studies, an electrical audit was carried out in a poultry slaughter cooler on the southwest region of Paraná. On the audit were established the centers of greater consumption and the baselines of the main energetic imputs and potential ways of electrical energy saving from the main thematic modules.It has been verified that the cooling system represents approximately 81% of electrical energy consumption of the plant and of the total of eleven modules; three of them represent approximately 97% of the power consumption of the entire plant, as engines, cooling system and compressed air system. It has been also found out, with an economic analysis of losses, there are potentials means of power saving, especially when it comes to engines. At last, was identified the main barriers to deploy an energy management system in a plant, mainly as regards the elaboration of baselines and indicators of electrical performance. These barriers have shown a fake expectation of the NPEE to reach the present goals if there's no impact on the progresses prompted (by public politics.)

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