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No description available.

Thesis (MScIng)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Thesis (M.S.)--Ohio University, March, 1986. / Title from PDF t.p.

Thesis (M.S.)--Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.

Previous work has shown that the risk of hearing loss is related to the cumulative sound energy received by the ear. The instrument which computes a measure of this parameter is an integrating sound level meter (ISLM). Optimum design requirements for ISLMs which meet a variety of demanding specifications have been determined. Evaluation procedures have been proposed and the necessary specialized tone burst signal sources have been designed. An early survey of instruments which were available revealed serious shortcomings in their ability tointegrate accurately a typical impulsive signal. The aim of this work was to determine and critically evaluate the limiting mechanism, and to subsequently investigate design strategies leading to high performance instruments. Techniques for extending the performance of several standard circuits have been developed. In addition, a novel method for storing data in analogue and digital form and subsequently recovering a continuous output has been developed and is fully described. Combinations of analogue, random logic and microprocessor-based techniques have been investigated. Complete instruments which utilize different combinations have been designed and evaluated. The optimum performance for an instrument which meets the highest specification is shown to be achieved by the use of analogue techniques for the majority of the signal processing, with a combination of random logic and microprocessor-based techniques for control and data storage.

M.Ing. / It is well known that all flow meters in common use are sensitive to the structure of the flow as it approaches the meter. A flow conditioner is a device installed upstream of for instance a flow meter to remove swirl and correct a distorted flow profile. Many flow conditioners are used in aviation, and in the mining and chemical industry and in the environment every year all over the world. Considerable research has been done on different flow conditioners. In the design and analysis of a flow conditioner, it is vital to have a proper understanding of its fluid mechanical properties. Recent work with computational fluid dynamics (CFD) method has shown that this technique can help to improve flow conditioner technology. The aim of this dissertation is to determine how the different parameters effect the flow performance of the perforated plate and attempt to modify the design. Nine different designs have been simulated by the CFD methodology and have been studied experimentally as well at a specific Reynolds number of 16000. The results obtained show that a different overall porosity can effect the performance of the plate when the other factors are kept constant; the thickness of plate is also a considerable factor for a perforated plate; and the difference in geometry is an important factor for the perforated plate conditioner.

A 10 GHz microwave bridge measurement system has been developed to automatically measure the electromagnetic field parameters transmitted through a dielectric material. These parameters are used to calculate the complex dielectric constant with the free-space transmission technique. The system is used to measure the field parameters transmitted through dimension lumber and a correlation is made with two strength determining factors of lumber: specific gravity and moisture content. Hemlock and Douglas Fir wood samples were tested and a grading technique was implemented. The system is capable of estimating the specific gravity to ±0.05 accuracy and the moisture content to ±3.0% accuracy. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The object of this work was to investigate the effect that heat losses from the "insulated" face of thin foil heat flux meters has upon the sensitivity of heat flux meters. In the past it has been characteristic of any analysis done on heat flux meters to assume that the insulation on the back face of the foil was a perfect insulator and thereby neglect the effects of heat losses from this "insulated" face. It is hoped that the information given in this thesis will be of value in determining how the geometric and heat transfer parameters affect the operation and sensitivity of heat flux meters. It is also hoped that this study will be of value in the design of heat flux meters and has advanced the state of the art of heat flux metering.