Thesis (M.A.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 114-120).

Thesis (M.B.A.)--University of Hong Kong, 1998. / Includes bibliographical references.

Thesis (M.A.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 114-120). Also available in print.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Abstracted in Dissertation abstracts, v. 17 (1957) no. 2, p. 261. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 237-249).

No description available.

Nos últimos vinte anos, alguns programas voltados ao atendimento de populações de baixa renda foram implementados por órgãos governamentais, inclusive empresas estatais fornecedoras de serviços públicos. No caso da empresa responsável pela distribuição de energia elétrica na Região Metropolitana de São Paulo, esses programas atuaram em um largo espectro de atividades, indo da implementação de redes de distribuição de eletricidade em favelas à administração de circos-escola. Devido às características de funcionamento da empresa e do contexto em que ela estava inserida, os chamados programas sociais não foram objetos de avaliações sistemáticas, o que possibilitou o predomínio de opiniões preconceituosas e não permitiu a definição de regras claras, que garantissem a continuidade dos seus benefícios. Com a transferência do controle das empresas distribuidoras para o setor privado, passa a ser ainda mais necessário o estabelecimento de normas para esse atendimento, dado o volume de pessoas atendidas por eles e a importância da energia elétrica no cotidiano. A Avaliação sistêmica dos programas da Eletropaulo voltados ao fornecimento de energia elétrica a núcleos residenciais de baixa renda aponta na direção de que esse tipo de atendimento pode ser viável para a concessionária e para a sociedade, se operados dentro de limites de uma regulamentação adequada, que garanta o equilíbrio entre todos os interesses. / During last twenty years, government, as well as state-owned companies, implemented many public programs in order to assist low income populations. In the specific case of Eletropaulo, the company responsible for the distribution of energy in the Metropolitan region of São Paulo, there was a large selection of activities, ranging from the implantation of electric grid in slums to the management of school-circuses. Due to particular operational conditions and the context of Eletropaulos situation, the so called social programs were not systematically evaluated. As a result, prejudice against these programs arouse and clear rules were not defined to guarantee continuous benefits. With the privatization of electrical energy distribution companies, it is even more necessary a clear regulation of these programs, given the volume of people served by them in addition to the importance of electrical power to all kinds of activities. Systematical evaluation of the program of electrical energy distribution in poor areas proves that it can be feasible both to the company and the society if the regulation guarantees the balance between all interests.

The health benefits of a national household electrification programme are investigated. Cognisance is taken of the lack of utilisation of electricity by newly electrified households. The impact of electrification on air pollution levels and paraffin utilisation is investigated to establish the effect on morbidity due to respiratory infection, paraffln poisoning and bums. The reduced demand for health services stemming from a reduction in morbidity is quantified and its macroeconomic implications investigated. The implications that the results of this quantification process holds for the financing requirements of a national household electrification programme as well as the microeconomic factors underlying the success of such a programme are highlighted. Chapter 1 outlines the methodology that will be used to firstly establish the expected switch to electricity as sole energy-carrier by newly electrified households, secondly to establish the health implications of such a switch, and thirdly to quantify these health implications. Chapter 2 reports the results of the modelling exercise, chapter 3 the resulting health implications and chapter 4 the quantification process. Chapter 5 looks at the macroeconomic implications of the health benefits of electrification. Chapter 6 investigates the impact of the results of this thesis on the financing requirements of the electrification programme. Bibliography: pages 63-68.

More than 20 million people in South Africa live without electricity in the household. Perhaps half of them live in underdeveloped rural areas in the 'homelands', which comprise about 14% of South Africa's land area. While considerable work has been done on methods of electrifying underdeveloped urban areas, little research has gone into the need for, and especially the cost of, electrifying the rural homeland areas. This dissertation documents an investigation into this question, using Ciskei as a sample area. The study is based on research that was carried out between July 1987 and January 1989. This research included a literature review of rural electrification and development, two field trips to Ciskei to gather relevant information, two questionnaire surveys to assess people's perceptions of electricity, and the design and costing of distribution and reticulation networks for a rural sample area in Ciskei.

Interfaces of water with water-repellent, or hydrophobic, materials are relevant in numerous natural and applied contexts. Examples include lotus leaves, membranes-assisted separation processes, and oil–water emulsions. Typically, water repellence is realized with the help of hydrocarbons and perfluorocarbons. Although these materials present low adhesion to water, their interfaces with water are known to be electrically charged. Origins of the electrification of water–hydrophobe interfaces is a century-old mystery that has been intensely debated on. A number of competing hypotheses have been proposed: specific interfacial adsorption of hydroxide ions, water dipole moment, partial interfacial charge transfer, specific interfacial adsorption of protons, cryptoelectrons, bicarbonate ions, and surfactant contamination. Given the significance of these interfaces, we investigated the origin of water–hydrophobe electrification. To disentangle the role of the various factors, we studied water’s interfaces with: solid hydrophobes, e.g., polypropylene; liquid hexadecane; and gas (air). Electrical charges incurred by water droplets formed using pipettes/tubes of hydrophobic (and hydrophilic) chemical make-up were quantified via electrometers and uniform electric fields. Specifically, we interrogated the contributions of water–hydrophobe surface area, surface chemistry, and water’s ionic strength, pH and dissolved CO2 content. We deduced that common solid hydrophobes have negatively charged surfaces even in air: when a hydrophobic pipette/tube is used to draw an aliquot of water from the bulk, hydrated cations form an electrical double layer at the liquid–solid interface. For the water–hexadecane interface, we tracked interfacial tensions over time. Our investigation revealed that trace amounts of impurities are present in the oil, despite purification, which interfere with purely interfacial effects. Lastly, we applied these fundamental insights to investigate slippery liquid-impregnated surfaces (SLIPS) realized using microtextured SiO2/Si wafers and sand dollar (Dendraster excentricus) templated PDMS surfaces. Recognizing the significant activity in triboelectric nanogenerators (TENGs), we conducted a parametric study of the device output and water–hydrophobe interfacial properties; and tested whether SLIPS could be incorporated in next-generation TENGs. The findings reported in this thesis address some long-standing questions on the spontaneous electrification of water–hydrophobe interfaces, and they should aid the rational development of practical applications such as SLIPS, TENGs, and beyond.

published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy