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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.
521

Territory and function : The electricity supply industry in Great Britain

Davies, P. January 1984 (has links)
No description available.
522

Performance characteristics of solar buffer zones for Scottish housing

Porteous, Colin D. A. January 1990 (has links)
No description available.
523

Aggression-related alcohol expectancies and exposure to community alcohol-related aggression among students at the University of the Western Cape

Toit, Renier du January 2010 (has links)
The relationship between alcohol consumption and alcohol-related violence has been firmly established in a wide array of studies concerning various forms of violence including intimate partner violence, domestic violence as well as sexual assault. One factor which has been highlighted as having a moderating effect on the relationship between alcohol consumption and alcohol-related aggression is the specific aggression-related alcohol expectancies concerning the effects of alcohol consumption on aggressive behaviour. In light of the prevalence of alcohol-related violence in South African communities it becomes important to examine the specific factors that moderate the relationship between alcohol consumption and alcohol-related aggression and violence. The aim of this study was to examine aggressionrelated alcohol expectancies as a moderating factor in the relationship between alcohol consumption and alcohol-related aggression and to examine the possible influence of exposure to community alcohol-related aggression in the formulation of aggression-related alcohol expectancies. The main objectives of this were to examine aggression-related alcohol expectancies as well as exposure to community alcohol-related aggression as domains for intervention to prevent alcohol-related violence. The focus is on establishing alternative areas for intervention aimed at the reduction of alcohol-related violence, specifically domestic violence and sexual assault, in South African communities. The sample was gathered through non-probability sampling methods and consisted of 262 undergraduate students from psychology courses. The study is a quantitative study employing a cross-sectional survey design. A significant relationship was found between alcohol consumption and alcoholrelated aggression with aggression-related alcohol expectancies moderating this relationship,leading to higher alcohol-related aggression. Exposure to community alcohol-related aggression did not predict aggression-related alcohol expectancies. / Magister Psychologiae - MPsych
524

The impact of energy efficient lighting on power networks.

Mansingh, Silesh. 12 September 2014 (has links)
The power utilities in many countries have come under stress as a result of generation capacity deficits, looming fuel costs and in many developing countries the electricity demand is very quickly outstripping the available electricity supply [1]. Since 2006, Eskom has been utilizing large scale residential efficient lighting roll out programmes as a cost effective short to medium term supply security solution while the longer term capital intensive supply side, “Build Programme” was underway [2]. This mostly involved the use of non-linear compact fluorescent lamps (CFLs) to replace linear incandescent lights (ILs) with very little involvement and influence by the utility QOS (quality of supply) engineers that are responsible for ensuring supply quality on the specifically targeted Distribution networks. This dissertation highlights that while CFLs can provide the desired energy or peak power reduction required, they can also have an impact on QOS within specific sensitive networks if the appropriate CFL standards (i.e. IEC 61000-3-2) minimum requirements are not adhered for both power factor and harmonics. These large scale CFL implementations have cost implications and hence metering and verification methods and models have been developed to simulate and quantify the returns from investing in energy efficient lighting initiatives. CFL manufacturers differ on ballast designs which have a direct impact on lamp efficacy, harmonic distortion and power factor which contribute to network quality of supply. It is for this reason that this dissertation raises an awareness of the importance of appropriate CFL standards i.t.o. the impact on quality of supply from a harmonics and power factor perspective. Due to the lack of more recent available or reliable sources of CFL test data, laboratory investigations were used to confirm the harmonics and PF characteristics of a variety of commercially available CFLs in addition to those utilised in previous large scale rollout programmes. The harmonics and power factor performance measured were compared for compliance against the international limits as prescribed in IEC 61000-3-2. Further investigations on international lighting industry standards for CFL’s has revealed gaps pertaining to harmonics and PF limits. This study is concluded by highlighting the impact of CFLs on power networks. It also provides a brief guide for utility power quality engineers by imparting an understanding of their role for the large scale efficient lighting programmes in order to pro-actively contain any possible impact on quality of supply within the regulatory limits as prescribed in the QOS standards. / M.Sc.Eng. University of KwaZulu-Natal, Durban 2013.
525

Reduced water consumption and related greenhouse gas emissions : A study of the effects of Uppsalahem’s watersavings campaign in 2013

Zisimopoulos, Dimitrios, Thor, Linnéa, Frisk, Malin January 2014 (has links)
The purpose of this project is to evaluate the effects of a campaign that Uppsalahem implemented in February 2013, in order to make their tenants consume less water. The result of the campaign is evaluated in terms of reduced water usage and reduced emissions of greenhouse gas related to the heating of the water through district heating. Four different residential areas in urban Uppsala, where Uppsalahem implemented their water saving campaign have been studied. All calculations are done in MATLAB. The results regarding water usage is presented in cubic meters and the greenhouse gas emissions are presented in terms of carbon dioxide equivalents. A sensitivity analysis of the data is performed in order to study natural occurring variances of water consumption over time. In order to determine which parameter has the greatest impact on reducing carbon dioxide emissions, a sensitivity analysis of the fuel mix used at the district heating power plant is made. The results show that there has been a reduction of water usage since after the campaign was implemented and the sensitivity analysis of the data indicates that there has been an especially large decrease in water consumption between the years 2012 and 2013. Further though, the results contain monthly irregularities in water usage in the different areas. This shows that the reduction of water consumption has not been temporally associated to the campaign, which indicates that the reduction might not be an effect of the campaign. Regarding carbon dioxide emissions, the sensitivity analysis indicates that the kind of fuel mix Vattenfall use at their district heating plant has a much greater impact than the individual water usage behaviors of the tenants.
526

Household response to fuelwood scarcity in South-eastern Botswana : implications for energy policy

Kgathi, D. L. January 1992 (has links)
No description available.
527

Evaluation of alternative thermal strategies for the precast concrete system houses in Jeddah, Saudi Arabia

Hashim, Nizar Hessain January 1991 (has links)
No description available.
528

Energy conservation and building design : A new approach to energy usage in Brazil, based on environmental planning

Perpetuo, J. E. January 1981 (has links)
No description available.
529

Energy utilisation and combined heat & power sizing in the health service

Williams, Jonathan Mark January 1998 (has links)
No description available.
530

State estimation and bad data detection in electrical power systems

Clewer, Bernard C. January 1986 (has links)
The thesis studies the subjects of bad data detection and state estimation in electrical power systems which are the processes whereby voltage, power flow and switch status measurements gathered continuously in real-time are used in conjunction with a model of the system to calculate the voltage levels at every node in the system. Traditionally the state estimation process requires two stages. The first stage is the pre-processing of the measurements by a bad data detector in an attempt to remove all the measurements which are grossly in error. The second is the calculation of the voltage levels by a state estimator from the remaining measurements which are likely to contain small random errors. Conventional state estimation algorithms are very sensitive to measurement errors, especially switch status errors, and unfortunately it is not possible to ensure that all the measurement errors are removed by the bad data detector. The thesis presents a new algorithm for state estimation utilising linear programming which is able to function in the presence of not only bad analogue measurements but also switch status measurement errors, thus removing the need for a bad data detector. The proposed method of state estimation is also able to include in its model of the system the individual busbars and bus-couplers within a substation. This feature enables the state estimation algorithm to process and provide additional network information thus leading to a more useful and reliable data base.

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