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A study on switching-surges of non-standard forms.Anis, Hussein Ibrahim January 1970 (has links)
No description available.
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THE ELECTRIC CURRENT DENSITIES BENEATH THUNDERSTORMS (CONDUCTIVITY).BLAKESLEE, RICHARD JUDSON. January 1984 (has links)
The Maxwell current density (J(s)), electric field (E), and positive and negative air conductivities were measured simultaneously under several thunderstorms at the NASA Kennedy Space Center (KSC), Florida, during the summer of 1981. The components of J(m) include displacement current as well as field-dependent (J(s)) and convection (J(c)) currents. The measurements under active storms show that: (a) J(m) is usually dominated by displacement currents when E is close to zero, (b) J(m) is steady with time in the intervals between lightning discharges, (c) J(m) is usually not altered significantly by lightning, and (d) the average values of J(m) change slowly over time scales that are comparable to those required for storm development. Field-mill data have been used to derive estimates of the time-average J(m), ‘J(m), under a number of storms at KSC in the years 1976-1978 and 1981. Maps of ‘J(m) are consistent with the locations of radar echoes and lightning charges, and the patterns of ‘J(m) develop and change shape slowly with time. Maximum values of ‘J(m) for large storms are typically on the order of 10 to 15 na/m², and those for small storms are 2 to 4 na/m². Since J(m) is a solenoidal vector, area-integrals of the ‘J(m) maps (‘I) on the ground provided at least a lower limit to the total storm current aloft. Maximum values of ‘I for small convective storms are on the order of 0.1 to 0.5 A, and the maximum values for large storms are at least 3 to 5 times larger. Attempts to infer the location, magnitude, and geometry of the current sources aloft from the field-derived estimates of ‘J(m) have been hampered by a 10-20% variance in the values of ‘J(m). These errors prevent a unique characterization of the current sources aloft unless other data can be included in the analysis. Polar conductivities have been found to be highly variable in a thunderstorm environment, but the total conductivity often remains comparable to that found in fair weather. Conductivities derived from Maxwell current estimates of Jₑ vs. E are about an order of magnitude larger than the direct measurements; therefore, the Jₑ vs. E method of estimating σ may not be valued.
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A study of corona loss and electric field distribution in bundle conductors.Jue, Shao-man. January 1971 (has links)
No description available.
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A study of corona loss and electric field distribution in bundle conductors.Jue, Shao-man. January 1971 (has links)
No description available.
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The Development of Teaching Aids for Elementary ElectricityBriggs, Cecil Lee 06 1900 (has links)
The purpose of this study is to develop a teaching program of instructional aids which will enrich the teaching of elementary electricity in the junior and senior high schools. It is hoped that the information and materials developed and presented will be of practical value to the teachers engaged in the teaching of electricity.
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An information system migration framework for the electricity industry control centersPlazaola Prado, Leonel January 2003 (has links)
<p>The Electricity Industry Reforms (EIR) is a worldwidephenomenon that is inducing an intensive business orientedcontext in the organization, processes and functions of theElectricity Industry (EI). The electric power grid is nowtreated as the electricity market, the consumer as thecustomer, the power system activities are related to marketactors (i.e. generators, distributors and retailers) and theElectricity Industry Control Centers (EICC) provide theessential coordination and economic trade functions andtransactions.</p><p>The EICC are looking for solutions to introduce, amongstothers, emerging information processes in the business orientedcontext with all the Electricity Industry actors without losingthe technical reliability of the EI. The EIR is delineated as amajor change on the traditional EI relying heavily oninformation exchange amongst the market actors.</p><p>In the Central American countries, these EIR started around1996. The EICC in this region are facing the demanded changeswith information legacy systems, in operation long time beforethe EIR and considered already obsolete.</p><p>This thesis exploresand summarizes, as a researchcontribution, the main problems at the EICCs in CentralAmerica, in managing the incorporation of emerging informationproc-esses.</p><p>An Information System Migration Framework (ISMF) for theEICC is proposed as a re-search contribution and solution tothe problems identified. The ISMF here presented provides a setof steps and guidelines to follow for managing any emerginginformation processes in a systematic, feasible and reliableway. The ISMF is a continuous description of emerginginformation processes, risk assessments, requirementelicitation and specifica-tions with traceable and incrementalimplementations without completely replacing the system. TheISMF has as fundamental characteristic that provides a feasibleview of the current operation of the EICC, a continuous anditerative process of controlled changes and a systematicprocess to update the EICC operation model with a set of stepsthat are implementation independent, technology independent,process ori-ented and user centered.</p><p>The ISMFs feasibility, replicability and useracceptance has partially tested at the EICC in El Salvador andNicaragua.</p><p><b>Key words:</b>Electricity Industry, Electricity IndustryReforms, Electricity Industry Control Centers, InformationSystem Migration, Information Systems Modeling andRequirements, Case Studies in the Electricity Industry inCentral America.</p>
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An information system migration framework for the electricity industry control centersPlazaola Prado, Leonel January 2003 (has links)
The Electricity Industry Reforms (EIR) is a worldwidephenomenon that is inducing an intensive business orientedcontext in the organization, processes and functions of theElectricity Industry (EI). The electric power grid is nowtreated as the electricity market, the consumer as thecustomer, the power system activities are related to marketactors (i.e. generators, distributors and retailers) and theElectricity Industry Control Centers (EICC) provide theessential coordination and economic trade functions andtransactions. The EICC are looking for solutions to introduce, amongstothers, emerging information processes in the business orientedcontext with all the Electricity Industry actors without losingthe technical reliability of the EI. The EIR is delineated as amajor change on the traditional EI relying heavily oninformation exchange amongst the market actors. In the Central American countries, these EIR started around1996. The EICC in this region are facing the demanded changeswith information legacy systems, in operation long time beforethe EIR and considered already obsolete. This thesis exploresand summarizes, as a researchcontribution, the main problems at the EICCs in CentralAmerica, in managing the incorporation of emerging informationproc-esses. An Information System Migration Framework (ISMF) for theEICC is proposed as a re-search contribution and solution tothe problems identified. The ISMF here presented provides a setof steps and guidelines to follow for managing any emerginginformation processes in a systematic, feasible and reliableway. The ISMF is a continuous description of emerginginformation processes, risk assessments, requirementelicitation and specifica-tions with traceable and incrementalimplementations without completely replacing the system. TheISMF has as fundamental characteristic that provides a feasibleview of the current operation of the EICC, a continuous anditerative process of controlled changes and a systematicprocess to update the EICC operation model with a set of stepsthat are implementation independent, technology independent,process ori-ented and user centered. The ISMFs feasibility, replicability and useracceptance has partially tested at the EICC in El Salvador andNicaragua. <b>Key words:</b>Electricity Industry, Electricity IndustryReforms, Electricity Industry Control Centers, InformationSystem Migration, Information Systems Modeling andRequirements, Case Studies in the Electricity Industry inCentral America. / NR 20140805
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Differences in electrical impedance measurements due to guarded/unguarded electrodes in homogeneous/inhomogeneous regionsReed, Wen-Yin F. January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Electricity Deregulation, Vertical Integration and the Importance of Independent Electricity RetailersDonald Burtt Unknown Date (has links)
Abstract The natural progression of generators and retailers, following electricity deregulation, to vertically integrate is a contentious subject involving, at one extreme, expectations that a laissez- faire market approach will deliver economic benefits to all participants, and at the other extreme, suspicions that the unusual features of the electricity sector, in providing generators with market power, may not provide electricity consumers with an improved outcome. The objectives of this thesis were to: understand fully the drivers of generators and retailers to vertically integrate and to apply this knowledge to the Queensland electricity market to determine the financial impact on generators, retailers and consumers from vertical integration (VI). A literature review was undertaken of VI in a generic sense, noting the distinction between market contracting and ‘internalisation’, with particular reference to the writings of Oliver Williamson. The Federal Court case involving Australia’s largest electricity retailer, Australian Gas and Light Ltd, seeking approval to purchase a minority shareholding in the Victorian generator Loy Yang Power, was closely examined from the perspectives of theoretical and practical electricity sector VI integration issues. A quantitative analysis was undertaken of an assumed 60% VI of the Queensland electricity market to assess the costs and benefits to generators that vertically integrated and to consumers. The quantified generator benefits included margin elimination, savings in overheads, more rapid decision-making, and demand side management (DSM) savings in deferred capital expenditure on peaking generation and network expenditure through reduced peak demand. To support the quantitative analysis, two scenario models were developed. The first model replicates the process by which generators build up revenue certainty over time from hedge contract sales and bidding of output into the electricity grid. How generator bidding behaviour is affected by the level of hedge cover and hedge contract prices is examined, particularly in regard to how this behavior is affected by the competitive relationship between retailers and generators. The second scenario model replicates the attitude of vertically integrated generators (VIGs) towards offering DSM services by observing how the attitude of individual VIGs is affected by level of peaking generation and by the generation-to-retailing output proportion. It was determined that a combination of these features and particular market scenarios could result in some VIGs being financially worse off by providing DSM services, an important conclusion in the context of the increased community focus on energy conservation. The extent to which VIGs pass on VI and DSM benefits to consumers was calculated under scenarios of weak and strong retail competition. Of most relevance was the difference in market behaviour between retailers that had became vertically integrated, and those that had not, with the latter expected to become less competitive in both the wholesale and retail markets. This outcome was observed to provide generators with additional market power potential, a subject closely examined. The quantitative analysis of the Queensland market concluded that the maximum possible benefit that consumers could expect from VI was $138 million per annum with current DSM technology and strong retail competition, increasing to $156 million per annum if DSM technology improved, for example in regard to more cost-efficient meters. Total possible benefits to VIGs and consumers was estimated at $321 million per annum, so that consumers could expect to receive no more than 50% of total expected benefits from VI. This conclusion is not surprising because generators will only seek to be vertically integrated if they perceive clearly identified benefits from VI. The reasons why consumers are unlikely to receive benefits greater than this are: • $30 million per annum of internal savings being retained by VIGs; • VIGs achieving a minimum $60 million per annum additional revenue benefits through wholesale and retail price increases, arising from their stronger generation and retail positions; and • $75 million per annum of potential DSM benefits not being offered to consumers, because of the reluctance of VIGs to provide DSM services where the outcome could be reduced export revenue, reduced sales revenue and lower pool prices. In summary, using the Queensland market as a case study, in a strongly competitive retail market consumers could expect to receive, at the most, 50% of VI and DSM benefits. However in a weakly competitive retail market, where VIGs retain most of the benefits and are able to achieve higher wholesale prices, the outcome could instead be an overall cost to consumers. The thesis concludes with a brief discussion of policy implications and approaches to addressing key issues arising from increasing VI in deregulated electricity markets.
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Air earth conduction current measurement by the direct methodBaugh, Raymond Chapman, 1933- January 1965 (has links)
No description available.
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