Computing the structure of a finite-dimensional algebra is a classical mathematical problem in symbolic computation with many applications such as polynomial factorization, computational group theory and differential factorization. We will investigate the computational complexity and exhibit new algorithms for this problem over the field \mathbb{F}_{q}(y), where \mathbb{F}_{q} is the finite field with q elements. In this thesis we will present new efficient probabilistic algorithms for Wedderburn decomposition and the computation of the radical.

Computing the structure of a finite-dimensional algebra is a classical mathematical problem in symbolic computation with many applications such as polynomial factorization, computational group theory and differential factorization. We will investigate the computational complexity and exhibit new algorithms for this problem over the field \mathbb{F}_{q}(y), where \mathbb{F}_{q} is the finite field with q elements. In this thesis we will present new efficient probabilistic algorithms for Wedderburn decomposition and the computation of the radical.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 44-48). Also available via the Internet.

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Decomposition, the process of breaking down organic material into its increasingly finer physical and chemical constituents, is an important component in the cycling of carbon and nutrients through an ecosystem. While ultraviolet (UV) radiation is known to be detrimental to human health, might it also play an important role in decomposition, and consequently soil fertility and land cover, in the arid southwestern US? To address this question, a 4-week field experiment was designed to quantify decomposition under contrasting radiant energy regimes at the Santa Rita Experimental Range near Tucson from July-August 2011. Velvet mesquite (Prosopis velutina) leaves were placed in litterbags constructed with fiberglass mesh and plastic that was either UV transparent or UV-B absorbing. The litterbags were deployed in open areas receiving full sun or in the shaded area beneath a shrub canopy. Leaf mass loss (an indicator of decomposition rates), soil-surface temperature, levels of photosynthetically active radiation, soil moisture, and precipitation were quantified over the 4-week period. UV (present vs. absent) and radiant energy environments (open areas vs. shaded) were compared using a mixed-effect model controlling for temporal autocorrelation. Soil-surface temperatures and decomposition rates in open areas were significantly higher (F1, 64 = 89.4, p < 0.0001; F1, 97 = 4.83, p = 0.0303, respectively) than those in shaded areas, but did not differ between UV treatments (F1, 97 = 0.064, p = 0.8012). These results suggest that over a short time period, radiant energy levels influence decomposition, but via temperature effects rather than via levels of UV.

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The distribution of bacteria in Sitka spruce stumps between one and ten years old was investigated by dilution plating wood chips taken from seven sampling positions up to 55 mm from the stump surface. The same wood chips were used to determine the presence Basidiomycotina within the stump wood. The number of bacterial colony forming units in the wood samples decreased in stumps between one and five years old, reaching a minimum after six years, before increasing in stumps up to ten years old. There was also a decline in numbers of bacteria isolated with increasing distance from the stump surface and the stump edge. A similar trend was detected in the diversity of the bacterial community. The size of the bacterial population was also correlated with stump moisture content. The presence of Basidiomycotina was associated with the presence of bacteria within the sample. However, the number of bacteria isolated from samples containing Basidiomycotina did not differ from that where no Basidiomycotina were isolated. Interactions between wood-decay fungi, including Heterobasidion annosum, and bacterial isolates were studied in vitro. The growth medium, timing of inoculations, and bacterial and fungal species tested were fund to significantly affect the outcome of the interaction. Bacterial isolates degraded cellulose, pectin and starch, cellulolytic ability increased with increasing stump age. Siderophores and chitinase, potential antifungal compounds, were produced by 29% and 2% of isolates respectively, however, these isolates had no effect on the distribution of Basidiomycotina in the stumps. Four groups of bacteria were identified from cluster analysis of 13 phenotypic characteristics. Different groups of bacteria were found to dominate bacteria isolated from stumps of different ages indicating that bacterial successions occur in decaying Sitka spruce stumps.

Thesis advisor: Edward J. Kane / Portfolio theory attempts to answer two fundamental questions concerning financial investments. In the language of the old adage "Don't put all of your eggs in one basket," the two questions arising are: 1) "How many baskets should the eggs be put into?" and 2) "How many eggs should be put into each basket?" / Thesis (PhD) — Boston College, 1972. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

by Ng Tsz Bun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iv / Table of contents --- p.v / List of Figure captions --- p.vii / List of Table captions --- p.xii / Chapter Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Sol-gel synthesis / Chapter 1.2 --- Ceramic Structures / Chapter 1.3 --- Dielectric Behaviour / Chapter 1.4 --- Ferroelectricity and Piezoelectricity / Chapter 1.5 --- Metal-Insulator-Metal system / Chapter 1.6 --- Space Charge Limited Currents / Chapter Chapter 2 --- Sample Preparation and Characterisation Methods --- p.27 / Chapter 2.1 --- Preparation of Precursor Solution bya New Chemical Route / Chapter 2.2 --- Preparation of Precursor Solution for SrTi(1_x)Nbx03 Thin Films / Chapter 2.3 --- Sample Preparation / Chapter 2.4 --- Chemistry of the Sol-gel Process / Chapter 2.5 --- Rutherford Backscattering Spectrometry (RBS) / Chapter 2.6 --- X-ray Diffraction (XRD) / Chapter 2.7 --- X-ray Photoelectron Spectroscopy (XPS) / Chapter 2.8 --- Atom Force Microscopy (AFM) / Chapter 2.9 --- Transmission Electron Microscopy (TEM) / Chapter Chapter 3 --- Characterization of composition and thickness of SrTi03 thin Films --- p.48 / Chapter 3.1 --- Composition Characterization / Chapter 3.2 --- Thickness Characterization / Chapter Chapter 4 --- Structural Properties of STO Thin Films --- p.57 / Chapter 4.1 --- Effects of Annealing Method on STO Thin Film Structure / Chapter 4.2 --- Substrate Effects on Structure of STO Thin Films / Chapter 4.3 --- Effects of Si02 Buffer Layer on Structure of STO Thin Films / Chapter 4.4 --- Effects of STO Film Thickness on Structure of STO Thin Films / Chapter 4.5 --- Surface Morphology of STO Thin Films / Chapter Chapter 5 --- Electrical Characterization of STO Thin Films --- p.78 / Chapter 5.1 --- C-V characteristics / Chapter 5.2 --- I-V characteristics / Chapter Chapter 6 --- Effect of Niobium Doping on The STO Thin Films --- p.100 / Chapter Chapter 7 --- Conclusions and Future Work --- p.109 / Chapter 7.1 --- Conclusions / Chapter 7.2 --- Future Work / Publications --- p.112 / Appendix --- p.113 / Preparation of Cross-sectional TEM Specimen

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