Includes bibliographical references. / Three problems are addressed in this dissertation. They are intracranial volume extraction, noise suppression and automated segmentation of X-Ray Computerized Tomography (CT) images. The segmentation scheme is based on a Seeded Region Growing algorithm. The intracranial volume extraction is based on image symmetry and the noise suppression filter is based on the Gaussian nature of the tissue distribution. Both are essential in achieving good segmentation results. Simulated phantoms and real medical images were used in testing and development of the algorithms. The testing was done over a wide range of noise values, object sizes and mean object grey levels. All the methods were first implemented in two- and then three-dimensions. The 3-D implementation also included an investigation into volume formation and the advantages of 3-D processing. The results of the intracranial extraction showed that 9% of the data in the relevant grey level range consisted of unwanted scalp (The scalp is spatially not part of the intracranial volume, but has the same grey level values). This justified the extraction the intracranial volume for further processing. For phantom objects greater than 741.51mm³ (voxel resolution 0.48mm x 0.48mm x 2mm) and having a mean grey level distance of 10 from any other object, a maximum segmentation volume error of 15% was achieved.

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Experiments were conducted to measure the thrust generated from a commercial jet engine. This thrust estimation was done using a pneumatic horn as the sound source with two arrays of microphones directly across the exhaust stream. The two arrays were separated by an axial distance downstream. Exhaust centerline measurements were taken at varying engine conditions, specifically; 30%, 50%, 60%, 70%, 80% and 100% engine power. An acoustic thrust estimation showed good agreement with measured thrust during the test campaign. In addition, a full traverse of the acoustic rig through the exhaust stream was completed for the purpose of tomography reconstruction. This reconstruction technique was able to pick up key features of the flow field. / Master of Science / A non-intrusive acoustic approach was used to measure the thrust produced by a commercial jet engine at all engine power levels. This acoustic approach was comprised of a sound source and receiving microphones placed on either side of the jet exhaust stream, just behind the engine. The acoustic measurements were compared to measurements by a load cell on the engine and showed excellent agreement. After the concept was proven, another experiment was conducted in which the sound source and microphones were moved vertically alongside the engine exhaust stream. These line of sight measurements were used to reconstruct the velocity and temperature gradients generated by the jet engine. The reconstructions showed good agreement with the engine geometry and was able to detect key flow features.