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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.
251

Technology policy, network governance and firm-level innovation in the software industry : a study of two Brazilian software networks

Costa, Janaina Oliveira Pamplona da January 2012 (has links)
This thesis examines how regional level network governance and structure influence the effectiveness of technology policy to improve local firms' innovativeness in a developing country context. It examines whether network governance and structure have a consistent influence on the innovative performance of firms located in developing country regions that show different levels of socio-economic development. The empirical evidence is based on a multiple case study of two regional software networks in Brazil – Campinas and Recife – in the period 2006 to 2009. Studies show that regional networks and industry growth in developed countries involve some degree of co-evolution. Networks are supposed to foster firm-level innovation, since government policies tend to assume that firms learn by interacting and that new knowledge is essential for innovation. Inspired by these findings, governments in developing countries often seek to address industry and regional development by encouraging the formation of regional networks. Policies aimed at supporting development of networks have become an important instrument to support interaction among firms, and between firms and other network actors. However, the investigation of networks, and especially the formation of dyadic ties and network consistency, is rarely the subject of empirical work on developing countries' innovation systems. Existing studies of networks tend to provide little empirical evidence on multi-organisational interaction and often do not investigate the related controlling mechanisms, which are crucial for a better understanding and more effective policies. This thesis, using a single analytical framework, provides a study of technology policy, multi-organisational network governance and structure, and firm level innovative performance. The research examines two Brazilian software industry networks established in the early 1990s, promoted by a national government programme to support the formation of regional networks. The histories of the information and communication technology (ICT) industries in the two regions are very different. The ICT industry in Campinas benefited from long-term national support, while the ICT industry in Recife received little direct support through national policies. The history of each network (i.e. infancy and evolution) is described until 2009. National government programmes to support these networks were complemented by local and state level policies aimed at developing the respective regional software industries. We observe the innovative performance of local firms participating in these regional networks in the period 2006-2009. The finding from this doctoral research is that network governance and structure had a mixed influence on the effectiveness of government technology policy to promote firm-level innovation in the networks investigated; the thesis sets out some of the reasons for the differences in firm level innovative performance in the two networks.
252

Industrial electric load modeling.

Manichaikul, Yongyut January 1978 (has links)
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / Ph.D.
253

Avaliação do desempenho de empresas de energia elétrica no Brasil sob a ótica de variáveis ambientais, sociais e de governança corporativa / Evaluatioi of the performance of electric utilities companies in Brazil from the perspective of environmental, social and corporate governance variables

Maria Raquel Siqueira Marques da Costa 06 December 2018 (has links)
O presente trabalho buscou avaliar o desempenho de empresas de energia elétrica no Brasil sob a ótica de variáveis ambientais, sociais e de governança corporativa (ESG - sigla inglesa para environmental, social and governance). Para tanto, concentrou-se na análise das companhias de capital aberto que reportam informações sobre suas iniciativas em sustentabilidade, no período de 2010 a 2015. Inicialmente, foi realizada revisão teórica acerca dos conceitos de finanças corporativas, sustentabilidade, valor compartilhado, materialidade e da relação entre mercado financeiro e sustentabilidade, com foco no investimento responsável. A análise quantitativa utilizou de variáveis ESG e econômico-financeiras de dez empresas. Foram realizados três estudos, por meio de regressões com dados em painel, avaliando a relação entre desempenho, caracterizado neste estudo por ROE (sigla inglesa para return on equity), e as variáveis explicativas. O primeiro estudo, que analisou a relação entre ROE e as variáveis ESG, não se mostrou estatisticamente significante, posto isso, não foi possível explicar o desempenho de empresas a partir somente das variáveis ESG. O segundo estudo, que adicionou à primeira análise os indicadores econômico-financeiros, apresentou quatro variáveis estatisticamente significantes, demonstrando que o desempenho de empresas pode ser explicado por variáveis ESG e econômico-financeiras em conjunto: (i) investimento em iniciativas de sustentabilidade; (ii) independência do conselho de administração; (iii) seguro D&O (Directors and Officers Liability Insurance) para administradores e conselheiros; e (iv) margem líquida. Por fim, o terceiro estudo buscou verificar o impacto da medida provisória nº 579 de 2012 (MP579) e apresentou resultado divergente ao esperado pela literatura, não sendo possível afirmar que a edição da MP579 afetou negativamente a rentabilidade das empresas do setor elétrico no Brasil. Este trabalho demonstra que a análise de indicadores ESG não deve ser dissociada da análise de indicadores econômico-financeiros. / The present study aimed to evaluate the performance of electric utilities companies in Brazil from the perspective of environmental, social and corporate governance (ESG) variables. Therefore, it focused on the analysis of public companies that report on their sustainability initiatives, from 2010 to 2015. Initially, a review of literature was made about corporate finance, sustainability, shared value, materiality and sustainable finance, focusing on responsible investment. The quantitative analysis used ESG and economic-financial variables of ten companies. Three studies were carried out, using regressions with panel data, evaluating the relationship between performance, characterized in this study by ROE (return on equity), and independent variables. The first study, which analyzed the relationship between ROE and ESG variables, was not statistically significant, given that, it was not possible to explain the performance of firms based only on ESG variables. The second study, which added to the first analysis the economic and financial indicators, presented four statistically significant variables, demonstrating that the performance of companies can be explained by ESG and economic-financial variables together: (i) investment in sustainability initiatives; (ii) independence of the board of directors; (iii) D&O insurance (Directors and Officers Liability Insurance) for directors and officers; and (iv) net margin. Finally, the third study sought to verify the impact of provisional measure No. 579 of 2012 (MP579) and presented a different result than expected in the literature, the results showed that it is not possible to state that the MP579 had a negative impact on the profitability of companies in the Brazilian electric utilities sector. This work demonstrates that the analysis of ESG indicators should not be dissociated from the analysis of economic and financial indicators.
254

Energy wheeling viability of distributed renewable energy for industry

Murray, William Norman January 2018 (has links)
Thesis (Master of Engineering in Electrical Engineering))--Cape Peninsula University of Technology, 2018. / Industry, which forms the lifeblood of South Africa’s economy, is under threat as a result of increased electricity pricing and unstable supply. Wheeling of energy, which is a method to transport electricity generated from an Independent Power Producer (IPP) to an industrial consumer via the utility’s network, could potentially address this problem. Unlike South Africa’s electricity landscape, which is highly regulated and monopolized by Eskom, most developed countries have deregulated their electricity market, which has led to greater competition for electricity supply. This thesis, presents an evaluation of the economic viability and technical concerns arising from third party transportation of energy between an IPP and an industrial consumer. IPP’s are able to generate electricity from various renewable distributed generation (DG) sources, which are often physically removed from the load. In practice, electricity could be generated by an IPP and connected to a nearby Main Transmission Substation (MTS) in a region with high solar, wind or hydropower resources and sold to off-takers a few hundred kilometres away. Using two software simulation packages, technical and economic analysis have been conducted based on load data from two industrial sites, to determine the viability of wheeling energy between an IPP and off-taker. The viability will be evaluated based on levelized cost of electricity (LCOE); net present cost (NPC); DG technology; distance from the load; available renewable resources; impact on voltage profile, fault contribution, thermal loading of the equipment and power loss. The results from both case studies show that the impact of DG on the voltage profile is negligible. The greatest impact on voltage profile was found to be at the site closest to the load. Asynchronous and synchronous generators have a greater fault contribution than inverter-based DG. The fault contribution is proportional to the distance from the load. Overall, thermal loading of lines increased marginally, but decreased based on distances from the load. Power loss on short lines is negligible but there is a significant loss on the line between the load and DG based on the distance from the load. Electricity generated from wind power is the most viable based on LCOE and NPC. For larger wind systems, as illustrated by the second case study, grid parity has already been reached. Wheeling of wind energy has already proven to be an economically viable option. According to future cost projection, large scale solar energy will become viable by 2019. The concept of wheeling energy between an IPP and off-taker has technical and economic merit. Wheeling charges are perceived to be high, but this is not the case as wheeling tariffs consist of standard network charges. In the future, renewable energy will continue to mature based on technology and cost. Solar energy, including lithium-ion battery back-up technology, looks promising based on future cost projections. Deregulation of the electricity market holds the key to the successful implementation of energy wheeling as it will open the market up for greater competition.
255

An Assessment Model for Energy Efficiency Program Planning in Electric Utilities: Case of the Pacific of Northwest U.S.A.

Iskin, Ibrahim 02 June 2014 (has links)
Energy efficiency stands out with its potential to address a number of challenges that today's electric utilities face, including increasing and changing electricity demand, shrinking operating capacity, and decreasing system reliability and flexibility. Being the least cost and least risky alternative, the share of energy efficiency programs in utilities' energy portfolios has been on the rise since the 1980s, and their increasing importance is expected to continue in the future. Despite holding great promise, the ability to determine and invest in only the most promising program alternatives plays a key role in the successful use of energy efficiency as a utility-wide resource. This issue becomes even more significant considering the availability of a vast number of potential energy efficiency programs, the rapidly changing business environment, and the existence of multiple stakeholders. This dissertation introduces hierarchical decision modeling as the framework for energy efficiency program planning in electric utilities. The model focuses on the assessment of emerging energy efficiency programs and proposes to bridge the gap between technology screening and cost/benefit evaluation practices. This approach is expected to identify emerging technology alternatives which have the highest potential to pass cost/benefit ratio testing procedures and contribute to the effectiveness of decision practices in energy efficiency program planning. The model also incorporates rank order analysis and sensitivity analysis for testing the robustness of results from different stakeholder perspectives and future uncertainties in an attempt to enable more informed decision-making practices. The model was applied to the case of 13 high priority emerging energy efficiency program alternatives identified in the Pacific Northwest, U.S.A. The results of this study reveal that energy savings potential is the most important program management consideration in selecting emerging energy efficiency programs. Market dissemination potential and program development and implementation potential are the second and third most important, whereas ancillary benefits potential is the least important program management consideration. The results imply that program value considerations, comprised of energy savings potential and ancillary benefits potential; and program feasibility considerations, comprised of program development and implementation potential and market dissemination potential, have almost equal impacts on assessment of emerging energy efficiency programs. Considering the overwhelming number of value-focused studies and the few feasibility-focused studies in the literature, this finding clearly shows that feasibility-focused studies are greatly understudied. The hierarchical decision model developed in this dissertation is generalizable. Thus, other utilities or power systems can adopt the research steps employed in this study as guidelines and conduct similar assessment studies on emerging energy efficiency programs of their interest.
256

Impact Analysis of Increased Dispatchable Resources on a Utility Feeder in OpenDSS

Eppinger, Crystal 07 July 2017 (has links)
Oregon utilities are replacing their portfolios of traditional fossil fuel generation with renewable generating sources. Stepping away from carbon-producing energy will leave a deficit of on-demand power, resulting in decreased reliability. To overcome these technical challenges, utilities must maximize the use of their present dispatchable resources. One such resource is the Portland General Electric (PGE) Dispatchable Standby Generation Program (DSG), which is an aggregated 105 MWs of distributed generation (DG). These resources are brought on-line when there is a critical need for power. Resources are added to the program if a transfer trip scheme is in place or a modeling study reveals that the feeder load is at least three times the generator capacity. If the load-to-capacity ratio were lower, more assets could be added to the DSG program. To investigate the impacts of lowering the DG load-to-capacity ratio on existing distribution feeders, we use Open-Source Distribution System Simulator (OpenDSS). We modeled the Oxford Rural feeder by converting a utility CYME database to instantiation files using several MATLAB programs. A MATLAB control program varies the load-to-capacity ratio of the OpenDSS feeder model and monitors the generator behavior immediately following a fault. We analyzed the results to determine the ideal load-to-capacity ratio that prevents unintentional islanding. The results show that the instantaneous (50) relay element settings dictate both the minimum load-to-capacity ratio and the maximum DG capacity. The present three-to-one ratio is very conservative and can be reduced. Additional dispatchable resources include a five MW battery-inverter system currently used as grid-back up. The battery is grid-tied to a 12.4 kV feeder making it an ideal candidate for conservation voltage reduction (CVR). Using the same feeder model, we investigated the effects of lowering the system voltage to the allowable minimum using injections of reactive power. A lower system voltage reduces the load at peak times. Conversely, increasing the voltage prevents generation conflicts. To determine the benefit of CVR by VAr-injection on the Oxford Rural feeder, we created a MATLAB optimization program to output the optimal feeder voltage for reduced system power. We use a Simulink feedback model to determine the appropriate reactive power needed to achieve the voltage change. We analyze the system model to reveal that the feeder is ideal for CVR but the system capacity must be increased to achieve the maximum power reduction.
257

What are the outcomes and who benefits from the restructuring of the Australian electricity sector?

Chester, Lynne, Social Sciences & International Studies, Faculty of Arts & Social Sciences, UNSW January 2007 (has links)
The last decade has delivered rapid structural change to the Australian electricity sector. The common conceptualisation of the sector's restructuring has been narrowly based around sector-specific regulatory change and the creation of a national electricity market. This thesis argues that such a focus provides an incomplete and inaccurate explanation of the transformation. Three closely interrelated layers of policies and actions embodying the precepts of neoliberalism, and implemented by the state, have driven the sector's transformation. These policies and actions transcend 'electricity-centric' policies and encompass policies which have become systemic to the Australian public sector as well as a third layer which has transformed the prevailing industrial paradigm across all industry sectors. The drivers of the electricity sector's restructuring -- and the outcomes and beneficiaries arising -- form the core research focus of this thesis. The research task is addressed by using the analytical framework of the French theory of r??gulation. The analysis reveals that the electricity sector has been Australia's second largest contributor of privatisation proceeds, remains dominated by government ownership and has falling levels of foreign ownership. Higher relative wage levels and union membership are also evident as have been job losses and substantial real price increases for households whereas those for business have generally fallen. The purported 'reform' centrepiece, the national electricity market, was found to be increasingly uncompetitive due to its own regulatory regime and market manipulation by government-owned companies. In addition, the sector exhibits a heightened precariousness: an unprecedented financial vulnerability arising from a strong appetite for debt and derivatives and exacerbated by payments to government owners not by new investment in generation capacity; increasing tensions between the nation-state and local-state concerning the national electricity market and compromises with labour; and an exposure to political and financial risks from the sector's global integration. The clear winners from the sector's restructuring are the owners of capital and the state, particularly the local-state, although the sustainability of this situation is questionable. The analysis also generates a number of propositions about the application of r??gulation theory to sector-based research.
258

The corporatisation of a bureaucracy : the State Electricity Commission of Victoria 1982 to 1992

Evans, Thomas Edward, 1947- January 2001 (has links)
Abstract not available
259

A holistic approach to the management of electrical assets within an Australian supply utility

Brown, Colin, University of Western Sydney, Sydney Graduate School of Management January 2005 (has links)
Asset-rich organisations (utilities) within Australia have entered into an era of environmental change, imposed largely by successive Federal and State Governments wanting to exact financial returns from these State Owned Corporations (SOCs). These changes have created a shift in the paradigms within which these organisations currently operate. Long established principles are being revisited, and processes re-engineered, to allow them to implement the changes needed to obtain improved efficiencies and achieve overall business success. It is this drive to break down the barriers and practices of the past that has led to the need to develop a fundamental understanding of what it means to take a holistic approach to the management of the physical assets owned by utilities. / Doctor of Business Administration (D.B.A.)
260

Smart sensors for utility assets

Moghe, Rohit 15 May 2012 (has links)
This dissertation presents the concept of a small, low-cost, self-powered smart wireless sensor that can be used for monitoring current, temperature and voltage on a variety of utility assets. Novel energy harvesting approaches are proposed that enable the sensor to operate without batteries and to have an expected life of 20-30 years. The sensor measures current flowing in an asset using an open ferromagnetic core, unlike a CT which uses a closed core, which makes the proposed sensor small in size, and low-cost. Further, it allows the sensor to operate in conjunction with different assets having different geometries, such as bus-bars, cables, disconnect switches, overhead conductors, transformers, and shunt capacitors, and function even when kept in the vicinity of an asset. Two novel current sensing algorithms have been developed that help the sensor to autonomously calibrate and make the sensor immune from far-fields and cross-talk. The current sensing algorithms have been implemented and tested in the lab at up to 1000 A. This research also presents a novel self-calibrating low-cost voltage sensing technique. The major purpose of voltage sensing is detection of sags, swells and loss-ofpower on the asset; therefore, the constraint on error in measurement is relaxed. The technique has been tested through several simulation studies. A voltage sensor prototype has been developed and tested on a high voltage bus at up to 35 kV. Finally, a study of sensor operation under faults, such as lightning strikes, and large short circuit currents has been presented. These studies are conducted using simulations and actual experiments. Based on the results of the experiments, a robust protection circuit for the sensor is proposed. Issues related to corona and external electrical noise on the communication network are also discussed and experimentally tested. Further, optimal design of the energy harvester and a novel design of package for the sensor that prevents the circuitry from external electrical noise without attenuation of power signals for the energy harvester are also proposed.

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