Orientador: Milton Dall'Aglio Sobrinho / Banca: Fernando Braz Tangerino Hernandez / Banca: Paulo Kroeff de Souza / Resumo: Este trabalho teve o objetivo de avaliar os medidores de vazão com uma ou múltiplas tomadas de pressão em sistemas de água. Esses medidores de vazão são de fácil construção, utilizando materiais de baixo custo, podem ser instalados em locais que apresentem perfis de velocidades axialmente assimétricos em decorrência da existência de singularidades e/ou incrustações internas. Este estudo também foi idealizado para auxiliar os programas de redução de perdas físicas de água, uma vez que existe uma demanda reprimida na instalação de medidores de vazão em redes públicas de abastecimento. O trabalho foi desenvolvido em escala real nas instalações da ETA de Presidente Prudente-SP que abastece a zona de distribuição denominada de Alto ETA. Como padrão de medição foi utilizado um tubo de Pitot do tipo Cole, calibrado em túnel de vento pelo IPT. Além da aferição em diversos perfis de velocidade, medidores de múltiplos furos foram instalados em vários locais da rede, o que proporcionou uma verificação do comportamento do medidor em relação à variação do tipo de materiais e diâmetros das redes de abastecimento e uma avaliação geral do seu emprego em condições reais de uso em sistemas de abastecimento público. Os resultados demonstram que o medidor multifuros foi menos sensível à variação do perfil de velocidades, ou seja, a utilização da curva de calibragem obtida em condições ideais numa situação de perfil assimétrico levou a erros de medição menores que os obtidos com medidor de tomada única. A possibilidade de contar com um medidor de vazão adequado às condições brasileiras, de baixo custo e facilidade de construção, abre perspectivas para alavancar os programas de redução de perdas físicas de água, uma vez que existe uma grande demanda reprimida na instalação de medidores de vazão em redes de abastecimento público. / Abstract: This work had the objective of evaluating the flow meters with one or multiple orifices in water supply systems. Those flow meters are of easy construction, using inexpensive materials, and can be installed in places that present asymmetric velocity profiles as a consequence the existence of singularities and internal incrustations. This study was also conceived to aid the programs of reduction of physical losses of water, since a repressed demand for flow meters exists in water distribution systems. The work was developed in real scale in the Water Treatment Station - ETA of Presidente Prudente city-SP, that provisions the zone of distribution denominated High ETA. The measurement standard was a Pitot-Cole meter calibrated in wind tunnel by IPT. Besides calibration in several velocity profiles, meters of multiple orifices were installed at several places of the net, that provided a verification of the behavior of the meter related to the variation of the type of material and diameters of water distribution systems and a general evaluation of its employment in real conditions of use in public supply systems. The results demonstrate that the multi-port meter was less sensitive to the variation of the velocity profiles, in other words, the use of the calibration curve obtained in ideal conditions in a situation of asymmetric velocity profiles, led to smaller measurement errors than that obtained with a meter of only one orifice. The possibility to count on a flow meter adequate to the Brazilian conditions, inexpensive and easily constructed, opens perspectives for support the programs of reduction of physical losses of water, since there is a great unsatisfied demand for flow meters in water public supply systems. / Mestre

It was this writer's problem to determine which of these two contentions is correct; i.e., to find out whether or not it is possible for a person to perceive a difference in 2/4 and 4/4 meters by listening to the accents. It was felt that a large group of college music students and faculty members should provide satisfactory subjects for this experiment. If, as a result of this experiment, it was found that these trained musicians could actually discriminate between the simple meter and its compound with any marked degree of consistency, it would then be admitted that the difference in the two meters is important. If, however, it was found that even musicians, who knew the technical distinctions between 2/4 and 4/4, could not really hear the difference in the two when the music was played by competent performers, it would then be contended that no important difference exists.

Wet Gas Metering is becoming increasingly important to the Oil and Gas Industry. In this research a wet gas flow is defined as a liquid / gas two-phase flow that has a gas mass content greater then 50 %. The Venturi Meter is a favoured wet gas meter in the Oil and Gas Industry. However, industry's understanding of wet gas flow phenomena in such a meter is limited and is therefore forced to accept large metering errors when existing correlations are used to take account of the liquid presence. Furthermore, these correlations all require an input value for the liquid flowrate. This information is not readily available to natural gas production engineers. This research extensively discusses the current wet gas metering situation and then uses new independent data from the NEL Wet Gas Loop to compare the performance of existing correlations when used with a Venturi Meter. This new data is examined to determine parameters that effect the meter reading and then new correlations are presented. One new correlation offered uses the additional information from a downstream pressure tapping in conjunction with the traditional upstream pressure reading and the Venturi pressure differential to predict the gas flowrate without knowledge of the liquid flowrate.

No description available.

Every year, clean, readily available water becomes more and more scarce. Metering water usage is a way to make users more aware of how much water they use, which in turn will increase the desire to conserve water and to reduce their water bill. When meters are tested in their new condition, it is normally performed under ideal laboratory conditions at constant flow rates. Then when the meters are installed in the field, they often are installed in or experience non-recommended conditions that are quite different from the ideal laboratory setting. This study investigated several non-recommended conditions that can exist in a distribution system. The conditions that were simulated were endurance (the study of accuracy as a function of meter throughput), installation (the study of accuracy as a function of upstream piping and meter mounting effects), and flow profile (the study of accuracy as a result of dynamic real world flow variances over time). The meter types that were tested in this study were displacement piston, nutating disc, multi-jet, single-jet, fluidic oscillator, magnetic, and ultrasonic. When comparing the results between the meter types it was found that some meter types were more susceptible than others to the conditions that were simulated. Displacement piston and nutating disc meters had the best overall accuracy performance under the three non-recommended conditions that were simulated.

In recent years, the Smart Grid has grown to be the solution for future electrical energy that promises to avoid blackouts as well as to be energy efficient, environmentally and customer-friendly. In Smart Grid, the customer-friendly applications are a key element that provides the feature for recognizing the active expenditure of current energy via an Advanced Metering Infrastructure (AMI) subsystem. In fact, the smart meter, as a major part of AMI that is installed in residences, which provides more details about a consumer‟s usage. The smart meter measures hour-by-hour usage of a house, and then instantly transmits the record to the utility via two-way communications, unlike the previous electrical system that collects all usage monthly. However, the live measurement of the usage creates a potential privacy leak since each electrical usage records the behaviour of consumers in the home. Therefore, any communication channel between customers and utility should have some sort of confidentiality which protects consumer privacy. In reality, smart meters are generally located in an insecure area of the house (outside), therefore anyone can potentially tamper with the device, noting the fact that it is low-end device. As a result, there is a great possibility of compromising the smart meter, resulting in disclosure of consumer usage. Actually, the nature of a smart meter, and the cost constraints, create a challenge to secure the network. Therefore, the dual motivating problems are the protection of consumer privacy as well as achieving cost efficiency. In this research, we propose a new secure and compromise resilient architecture that continues two major components: a smart meters compromise attack detection scheme and a secure usage reporting protocol. Firstly, the smart meters compromise attack detection scheme improves the security of the smart meter, preventing an adversary from compromising the smart meter. Secondly, the secure usage reporting protocol improves the security of communication between the smart meter and the utility, preventing an adversary from identifying each household's usage reported by smart meters. / UOIT

Inaug.-diss.--Berlin. / Vita. "Sonder-abdruck aus 'Zeitschrift für psychologie und physiologie der sinnesorgane.' bd. XVIII."

Inaug.-Diss.--Berlin. / Vita. "Kommt hier nur der erste Teil der ganzen Arbeit zum Abdruck. Der Rest wird demnächst in der Zeitschrift für Psychologie erscheinen."

Thesis--Brandeis University, 1968. / Xerographic copy of typescript. Bibliography: leaves 162-167.

Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 288-297).