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Water is an important natural resource and a building block to all life on earth. However, substantial increase in water demand and consumption has led to numerous nations, including South Africa, to face water scarcity. Improved water demand management strategies and water monitoring approaches are imperative. In South Africa, it's a legal requirement for all water supply points to be metered. Currently, water flow is primarily measured by conventional meters. However, substantial developments have been noted in the last two decades where conventional meters with added capabilities (such as communication capabilities) added have been introduced. These meters are known as advanced water meters. These capabilities offer functions such as leakage detection and more immediate consumption feedback. However, advanced meters also have significant disadvantages such as require high start-up capital and are susceptible to higher failure rates than conventional meters. It remains to be seen if advanced metering technology is an appropriate technology to be adopted in South Africa. Due to the different dynamics of South Africa's income level groups, the metering application and effects will differ for each income level group. Therefore, the purpose of this study is to investigate the feasibility of implementing advanced metering systems in high income areas in South Africa. An evaluation framework was developed to gauge the viability of implementing advanced metering systems on four performance criteria; technical, economic, environmental and social. The composite indicator framework template was selected as it was not tailor made for a specific reason and could be adapted for this research. The necessary framework input parameter data were acquired from practitioners in the field through questionnaires and from literature. Due to lack of advanced metering case studies in South Africa (except for prepaid meter), literature from developed countries were used as proxies. The input data entailed details of the current metering system, advanced metering system and new conventional metering system with the later used as a control for comparative purposes. The typical high-income scenario was derived from typical input data. For each input parameter, there were value ranges from the low parameter value to high parameter value. These ranges were used to conduct the sensitivity analysis on the framework to access critical input parameters to the success or failure of implementation Implementing advanced metering systems in high income areas in South Africa was found to be less economically viable than conventional meters. This is due to the lack of needed infrastructure for advanced metering as well as high initial capital costs and high operating costs. Advanced meters however proved to be more environmentally viable than conventional meters as they offered higher reduction in consumption. However, the manner in which faulty batteries are disposed could lead to environmental damage. Social factors were considered negligible for high income areas as revolts to introduction to new meters arises from financial constraints that those meters might induce. Further research with more South Africa based case studies and smaller scale advanced metering systems has been recommended.

In multiphase flow, the velocity differences between phases means unless the velocities of individual phases and concentrations are known, the true flow rate is practically impossible to obtain. At present, there is no single multiphase flow meter design capable of providing the required accurate measurements of oil, water, and gas fractions, as well as the phase velocities of wet gas. This research thesis introduces a prototype multi-phase flow metering system, named Uletechement. The main objectives of this research is to provide individual phase velocities of wet gas, and to combine with phase volume fraction measurements to obtain individual phase volume flow rates for gas and liquid Hydrocarbon (HC). The system comprised of a camera, laser source, synchronizer, computer data acquisition system and MATLAB based software, gas liquid chromatograph, seeds and tracer injecting devices. The gas-phase velocity is determined based on Particle Imaging Velocimetry (PIV). An algorithm that correlates the cameradeveloped through this research. The computer acquires two sequential image signals from the camera, and carries out the calculation of cross correlation between the images so that the average particle displacement within each interrogation area can be found. The average gas-phase velocity is subsequently obtained by integrating pixel velocity along the distance between two image frames obtained by a Charged Couple Device (CCD) camera. The product of phase velocity and phase concentration gives the flow rate of gas phase. The HC condensate flow is measured by injecting the fluorescent tracer - Silicone Carbide (SiC) at a known flow rate, which mixes only with the condensate. By sampling and analyzing samples further downstream, the ratio of the fluorescence of the injected and sampled condensates are subsequently determined. And the HC condensate flow rate can then be derived. The proposed method has been tested using a rig at Shell laboratory for the samples with a range of phase fractions and at several different velocities and flow rates. Due to the limitation of the rig, simultaneous measurement of the gaseous and condensate flow rate could not be done. But the experiments for liquid HC and gaseous phase measurements were carried out separately. However, this did not devalue the validation. The test results have been analysed and provided in the thesis, which confirmed the concept of proposed method.

Flowing suspensions of solid particles in gas can be found in various industrial applications, as a method for transporting powdered solids (known as "pneumatic conveying"). The problem of measuring the mass concentration of the solid fraction has not yet been satisfactorily resolved. This thesis explores acoustic techniques to measure the particle concentration. Controlled suspensions -- both flowing and quasi-static - were generated in cylindrical tubes, and their acoustic properties were measured over three frequency ranges, requiring a variety of different measuring techniques: Plane wave region (200 -4 kHz): the attenuation of plane waves travelling along the flow tube was measured. A simple method of measuring the characteristic impedance of the suspension was also devised and preliminary measurements were made. Reverberant region (4 - 20 kHz). Three parameters were measured: the decay rate of the reverberant field in certain frequency bands; the level of actively-excited steady state sound; and the frequency of transverse resonant modes of the pipe. Ultrasonic region (40 - 75 kHz): the attenuation of ultrasound was measured across the pipe diameter. The measurements were compared with theoretical predictions. They showed the predicted linearity of acoustic attenuation with concentration, although the frequency dependence was less well predicted. In general, the larger particle sizes produced the greatest discrepancy; an explanation is proposed. Ultrasonic measurements showed significant differences from the predicted frequency dependence. A method of isolating acoustic transducers from the flow with a column of clean air is described. However, measurements may be complicated by interactions at the orifice into the flow pipe. Further work is needed in this area. It is concluded that acoustic methods could be used to measure particle concentration. However, to remain insensitive to changes in the properties of the particles - size in particular - measurements must be made at more than one frequency.

Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2007. / Wayne J. Book, Committee Chair ; Nader Sadegh, Committee Member ; Chris Paredis, Committee Member ; Bonnie Heck, Committee Member ; Roger Yang, Committee Member ; Renato D.C.Monteiro, Committee Member.

Advanced water metering is part of a much larger movement towards smart networks and intelligent infrastructure. However, where advanced metering technology is focused more towards the need to obtain meter readings without human intervention in other parts of the world, in South Africa and other developing countries, advanced water metering (in the form of prepaid meters or water management devices) has been developing along a parallel path, driven by the need to provide services to previously unserved communities and deal with the problems caused by rapid urbanisation. In this report, conventional water metering is defined as systems using water meters that display their readings on the meters themselves and advanced water metering as systems that add additional components or functionality to a metering system. Advanced metering has the potential to provide substantial benefits if appropriately applied. However, compared with conventional metering, these systems are considerably more expensive and complicated, and often rely on technology that is still being developed. Advanced metering systems therefore carry a higher risk of failure, poor service delivery and financial losses unless the system is implemented with careful design and thorough planning. This report describes a number of case studies of the application of advanced metering in South Africa. The case studies were evaluated according to the evaluation framework described in Appendix A and their detailed evaluations are included in each relevant chapter. Evaluations were done in four areas: technical, environmental, social and economic. The technical evaluation is based on the systems complying with the relevant national metering standards and good metering practice, the environmental evaluations on battery disposal and water savings and the social evaluation on broad socio-economic indicators. It should be recognised that social issues are particularly complex and that no general evaluation framework can accurately predict whether an advanced metering system will be accepted by a particular community. The economic evaluations were based on reductions of the current system cost and not absolute values. Economic performance indicators included the effective surplus (income minus expenses over averaged over the meter service life) and capital repayment period. An overview of lessons learned and conclusions from the case studies are provided in Chapters 8 and 9 of the report.

Actualmente, existe un incremento vehicular en Lima Metropolitana que perjudica la eficacia de las vías de comunicación terrestres. Por tal motivo, el presente tema de investigación tiene como finalidad reducir el grado de saturación en las intersecciones urbanas de la Av. Angamos Este con Av. Aviación, Av. Tomás Marsano y Av. República de Panamá ubicadas en Lima Metropolitana a través de la metodología Ramp Metering que considera desarrollar el algoritmo ALINEA. En primera instancia, se describió la situación actual de los cruces viales previamente mencionados, a partir del reconocimiento en campo. Posteriormente, se recopilaron los tiempos de verde efectivo vehicular y el ciclo semafórico peatonal. De igual manera, se contabilizó presencialmente el flujo de automóviles durante 13 horas continuas y el número de transeúntes en las intersecciones durante el mismo periodo. Subsiguientemente, se evaluaron las condiciones de circulación existente, donde el principal objetivo es determinar el grado de saturación por medio de flujogramas que permiten una mejor visualización del estado actual. Luego de lo mencionado, se empleó la estrategia ALINEA para diseñar una propuesta de mejora a partir los tiempos de verde efectivo calculados el algoritmo mencionado. Siguiendo con el procedimiento, se evaluó el diseño con el software PTV VISSIM 9.0, un programa de micro simulación acorde con los lineamientos planteados del proyecto, con la finalidad de verificar si existe una mejora relacionada al grado de saturación. Por último, se compararon las dos situaciones previstas, calculando el parámetro indicado con el programa VISSIM. / Currently, there is an exponential growth in the number of vehicles in Metropolitan Lima that harms the efficiency of the vehicle flow on the roads and highways of this city. For this reason, the present research topic aims to reduce the degree of saturation at the urban intersections of Av. Angamos Este with Av. Aviación, Av. Tomás Marsano and Av. República de Panamá located in Metropolitan Lima through the methodology of Ramp Metering that considers developing the ALINEA algorithm. In the first instance, the current situation of the previously mentioned crosses was described based on the recognition carried out in the field. Subsequently, the effective vehicular green times and the pedestrian traffic light cycle will be collected. In the same way, the traffic flow was collected for 13 consecutive hours and the number of passers-by at the intersections during the same period. Subsequently, the existing circulation conditions were evaluated, where the main objective is to determine the degree of saturation throughout flow charts that allow a better visualization of the current state. After the aforementioned, ALINEA strategy was used to design a proposal that improves the vehicle flow of the intersections based on the effective green times calculated by the algorithm mentioned. Following the procedure, the design is evaluated with the PTV VISSIM 9.0 software, a micro simulation program in accordance with the guidelines outlined in the project, with the purpose of verifying if there is an improvement related to the degree of saturation. Finally, the two situations foreseen were compared, calculating the indicated parameter with the arithmetic process of the micro simulator VISSIM. / Tesis

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Ingeniero Civil Eléctrico / El sistema eléctrico chileno deberá dar el siguiente paso si es que se quiere seguir con los lineamientos de energías limpias y eficiencia energética. La adaptación de la urbe a una más "inteligente" podría brindar la solución a la mayoría de los problemas concernientes a su integración, dándole también la oportunidad a nuevas tecnologías que favorecerían esta nueva ideología. Respecto a la integración y sus problemas, se resalta en esta ocasión la referente a frecuencia: se hará cada vez más notorio con la inserción de ciertas ERNC (generación sin inercia), por lo que se plantea la elaboración de un esquema de desconexión selectiva de cargas para paliar el efecto de falta de inercia en situaciones de contingencia. La elaboración, prueba, validación y evaluación del esquema fue realizada en el entorno DIgSILENT; ajustándose los parámetros necesarios mediante procesamiento de datos de perfil de consumo en la capital y apuntando a aplicaciones específicas que cumplieran un set de requisitos. Como comparación, se utilizan casos de estudios similares a los emitidos por la DO del CDEC para los estudios de EDAC. Los resultados finales auguran un buen desempeño en la parte técnica. Los beneficios percibidos apuntan a mejores niveles de frecuencia, pudiendo impedir la activación de hasta 4 etapas de EDAC si se enfoca y diseña apropiadamente el esquema. La flexibilidad del diseño permite priorizar resultados tanto para ciertos parámetros de evaluación, como para la magnitud de fallas que se quiera soportar. Económicamente aportaría ahorros no menores en una ventana de tiempo adecuada, aunque siendo sus atractivos principales el aporte técnico/operacional y el de formar parte de uno de los tantos esquemas aplicables que sustentarían la instalación de medidores inteligentes.