Thesis (M.F.A.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaf 18).

Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 156-172).

Thesis (Ph. D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 230-244).

Thesis (doctoral)--Helsinki University of Technology, 2008. / Includes bibliographical references. Also available on the World Wide Web.

The effects of processing variables on the microstructures, textures and press-formability of commercial 17 Cr, 0.05C (430) steel and low-interstitial Ti-stabilised 12 Cr (409) and 17 Cr (430 Ti) steels have been studied. The annealing textures have beencorrelated with tensile strain ratio measurements and from this correlation it has been possible to select combinations of cold rolling reduction and annealing treatments for texture control to improve deep drawability. Electron microscope examination has been used to identify possible nucleation mechanisms for the observed recrystallisation textures. Cold rolling texture development and tensile strain ratios have been discussed from theoretical considerations of slip in bcc metals. Pronounced differences in microstructural features between high interstitial 4-30 and low-interstitial Ti-stabilised steels are reflected in differences in texture development at all stages. Hot band condition is an important variable, affecting texture development during subsequent cold rolling and annealing. All three steels develop similar cold rolling textures, consisting mainly of ~{100} , ~{111} and ~{112} components. The ~{112} orientation is more prominent in 430 Ti steel than in 430 steel, and it is suggested that this difference may be due to irregular flow in high interstitial 430 steel. Other differences in cold rolling textures are attributed to texture inheritance from the hot band. Recrystallisation textures in 430 steel are mainly ~{114} , with ~{223} present after high reductions, and r-values are generally low. Recrystallisation textures in 409 and 430 Ti steels are mainly ~{110} after low cold rolling reductions, ~{554} after moderate or high reductions and -{223} after very high reductions. In most cases, ~{100} is only a minor component. Batch annealing of the hot rolled strip followed by cold rolling to 90% RA and rapid final annealing promotes maximum ~{554} intensity with low ~{100} intensity, and a correspondingly high r-value. The ~{223} and ~{114} orientations, attributed to grain boundary nucleation, have not been reported previously in 17 Cr ferritic stainless steels, although they have been reported occasionally in other low-carbon ferritic steels.

No description available.

Rheological measurements on intact fresh snap beans (Phaseolus vulgaris v.) and purees made from raw beans were used to assess the effect of variety and sieve size on the textural characteristics of green snap beans. Seed length, percentage dry matter and physical fiber measurements were used as textural quality indicators. Four varieties of green snap beans (Tendercrop, Rainier, Harvester and BBL 290) were tested in 1971 and 1972. Each variety was harvested five times in each year. Adverse environmental conditions in 1971 caused bean textural quality to be higher in 1972 than in 1971. The four varieties tested showed significant differences with Rainier exhibiting the best textural quality while Harvester generally showed the poorest quality. Tests involving the resistance to shearing of intact bean pods were carried out using the Ottawa Texture Measuring System and the Food Technology Corporation's Texture Test System (formerly the Kramer shear press). Viscosity tests were performed on purees composed of macerated raw green bean tissue and water. Results were obtained from spread test using a simplified Adams-type consistometer and from rotating coaxial cylinder tests using a Brookfield RVT Synchro-Lectric Viscometer fitted with a small sample adapter. The Brookfield data were then fitted to the power-law equation. Rheological parameters showed highly significant interrelationships in most instances. Viscous properties of purees (spread, m, n and yield stress) were highly correlated with percentage dry matter of the beans. Peak force readings of the Kramer shear press and the Ottawa Texture Measuring System were significantly correlated with all textural quality and viscometric parameters. / Land and Food Systems, Faculty of / Graduate

Image segmentation is a fundamental part in low level computer vision processing. It has an essential influence on the subsequent higher level visual scene interpretation for a wide range of applications. Unsupervised image segmentation is an ill-defined problem and thus cannot be optimally solved in general. Several novel unsupervised multispectral image segmentation methods based on the underlaying random field texture models (GMRF, 2D/3D CAR) were developed. These segmenters use efficient data representations that allow an analytical solutions and thus the segmentation algorithm is much faster in comparison to methods based on MCMC. All segmenters were extensively compared with the alternative state- of-the-art segmenters with very good results. The MW3AR segmenter scored as one of the best available. The cluster validation problem was solved by a modified EM algorithm. Two multiple resolution segmenters were designed as a combination of a set of single segmenters. To tackle a realistic variable lighting in images, the illumination invariant features were derived and the illumination invariant segmenter was developed. For the proper evaluation of segmentation results and ranking of algorithms, a unique web-based texture segmentation benchmark was proposed and implemented. It was used for comprehensive...

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In this work, understanding the microstructural effects on stress state and strain rate dependent plasticity, damage, and failure of aluminum and magnesium alloys were examined. Several experimental techniques were employed to implement the test data into a physics-based internal state variable plasticity-damage model. Effects arising from various strain rates, stress states, and material orientations were quantified and discussed within the framework of linking microstructural features to mechanical properties. The method developed for determining structure-property relations was validated by accurately capturing the effects for a variety of materials and loading conditions. The end result is a methodology capable of predicting the onset of damage and failure for a material loaded under complex dynamic conditions.