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The purpose of this research was to determine if installing a smaller air compressor could reduce the electrical usage of a large semiconductor manufacturing plant. A 200 horsepower Atlas Copco compressor was installed with the existing 500 horsepower Ingersoll-Rand compressors. Testing was conducted during the regular manufacturing process at MEMC Southwest in Sherman, Texas. Analysis of the data found that installing the new compressor could reduce electrical consumption. The study also found there are specific operational setpoints that allow the compressor to operate more efficiently.

This thesis describes a theoretical and experimental investigation into compressional wave ultrasonic probes for use in high resolution non-destructive testing. In the theoretical section, the pulse performance of the ultrasonic probe is analysed in detail. The response of the piezoelectric transducer is initially determined by direct time domain analysis of electrical equivalent circuits and specially devised computer programs are then used ito predict the performance of various probe constructions The effects of intermediate layers lying between the transducer and the backing and between the transducer and the job are included. In the experimental section, the design, construction and subsequent performance of high resolution probes is described. Both contact and immersion probes are included, the former having a resonant frequency of 5MHz, and the latter having resonant frequencies of 5MHz and 10MHz. Whilst the computer analysis does not extend to contact probes, agreement between predicted pulse shapes and those obtained experimentally is excellent in the case of immersion probes. In addition to pulse shapes, full details of such aspects as repeatability of probe performance, suppression of acoustic waves in the backing and experimentally observed beam-profiles are also given. Finally, the performance of a single immersion probe having a resonant frequency of 20MHz is described and some suggestions for further work are given.

A simple stand-alone Scanning Tunnelling Microscope has been designed and constructed with the aim of providing first stage toward an in-situ instrument for study of thin-film growth. It is functionally capable of STM operation (constant current, constant height, line test) and STS operation (I - V and dI/dv - V). This thesis describes mechanical design, electronic design, computer interfacing in hardware and software, and computer graphics, and presents the results of testing and some applications. The STM head mechanical design features a helical spring/diaphragm coarse approach assembly and a concentric tube scanner. An analysis of the control system indicates that an integrator and single-pole low-pass filter provides near optimal behaviour of the control loop and deals with mechanical resonance in a particularly satisfactory manner. A discussion of hardware/software tradeoff and analog/digital tradeoff leads to a stand-alone design based on a PC, giving good performance with maximum use of standard commercial components and relatively simple special-purpose interface. Commercial graphical software package UNIRAS PC-DOS is employed for image display and hardcopy output. Results show excellent repeatability and stability of STM operation, with atomic resolution.

CHDS State/Local / The availability and interoperability of communications at an incident scene have long been recognized as high-priority problems that need to be addressed to improve our nation's Homeland Security and preparedness. This thesis describes a proposed methodology to address these issues at the Incident Command level while enhancing situational awareness and information sharing. The thesis analyzes the results of a research project funded by the Department of Homeland Security at the University of Louisville's IT Research Center for Homeland Security. The problem being addressed is that the decision-maker with the boots on the ground, the Incident Commander, needs relevant information in the early stages of the emergency at the incident scene and an efficient way to communicate with other resources. The research project fielded a prototype solution based on readily available commercial off-the-shelf components integrated in a man-portable configuration to provide maximum flexibility, lower costs, and ease of operations. A proposed concept of operations in various prevention and response environments was also recommended in the thesis after analyzing the results of several field exercises and interviews with users. / Director, Information Technology Resource Center, University of Louisville