Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 241-275). Available also in a digital version from Dissertation Abstracts.

Today, housing dominates the majority of land use due partially to its horizontally organized living spaces which results in relatively large building footprints. As an alternative to this default horizontality, a vertically-oriented single family house is studied. The house takes advantage of the verticality by offering unusual spatial overlaps with a set of choreographed views corresponding to level and visibility distance of the surrounding terrain. / Master of Architecture

The vertical cliff-face habitat is renowned for many specifically adapted plant species that exhibit a high degree of local endemism. Over a period of nine years the succulents and bulbous succulents on cliff faces in South Africa and Namibia were systematically surveyed and documented. Distinction was made between succulents growing on cliffs as part of a wider habitat and those found only on cliffs (obligate cremnophytes). Most major cliff-face habitats in the study area were visited and all plants were documented. A check list and descriptions (including adaptive traits) of the 220 obligate cremnophilous taxa are provided. During the study some 45 new cremnophilous succulent taxa were discovered and named, representing almost 20% of the total and proving that cliff habitats are some of the least studied environments, not only in southern Africa but globally. Among the newly described cremnophilous taxa is the genus Dewinteria (Pedaliaceae). Using stem length, three basic cliff-face growth forms are identified - compact or cluster-forming ‘cliff huggers’, cliff shrublets or ‘cliff squatters’ and pendent ‘cliff hangers’. Compact growth (often tight clusters or mats) is mainly associated with the winter-rainfall Succulent Karoo and Thicket regions, especially Namaqualand. However, further north the same compact growth forms are associated with an increase in altitude such as the Drakensberg Escarpment and other northern mountains. Most pendent growth forms are associated with the eastern and southeastern summer-rainfall regions; a number of smaller pendent shrublets occur on the high quartzitic sandstone mountains of the Western Cape. The degree of specialisation varies from highly adapted (smaller percentage) to less specialised (often eco-forms), and some taxa have no obvious adaptations. This study revealed a general increase in succulence in most obligate cremnophilous succulent species (compared to closely related species in other habitats), a reflection of their xeric habitat, and plants tend to be more compact. Also, there is a shift in reproductive output, including an increase in vegetative reproduction (backup), wind-dispersed seed and enriched flowering associated with certain species. Most obligate cremnophilous succulent plants in the study area have cliff-adapted features, ensuring long-term survival. / Thesis (PhD)--University of Pretoria, 2012. / Plant Science / unrestricted

The contamination of inland surface water by point and nonpoint sources is a widespread human health concern. To address this problem, a thorough understanding of the sources and persistence of this pollution is necessary. Using fecal indicator bacteria (FIB) as a surrogate for enteric pathogens, the Environmental Protection Agency (EPA) and state agencies have developed surface water quality standards. If a segment does not meet these standards, a Total Maximum Daily Load (TMDL) must be developed for the watershed to identify sources of bacterial pollution. Currently, FIB pollution is the leading pollution type addressed by TMDLs in the country. One source of FIB identified in TMDLs is colonies of birds roosting under bridges. It has been proposed that the birds’ feces can augment the FIB concentrations downstream of bridges. In this year-long study of Bull Creek in Austin, Texas, it was determined that the concentrations of Escherichia coli and fecal coliform downstream of a bridge were significantly greater when migratory cliff swallows were nesting under the bridge. The downstream concentrations of both FIB exceeded contact recreation standards. Data also suggest that FIB from the feces could be swept into the stream by runoff from storm events. No enterococci loading was observed in conjunction with the swallows. This study also investigated the affects of sediment resuspension on surface water FIB concentrations and the persistence of FIB in shady, inland streams. The resuspension of sediments with attached FIB could also increase the FIB concentration in the water column and increase its persistence. The results of reactor-based experiments demonstrated that the concentration of E. coli in water from an effluent-dominated stream increased by a factor of 3 when riverine sediments were resuspended and exceeded single sample standards for contact recreation, suggesting sediments as a reservoir of E. coli. Additionally, concentrations of E. coli decreased by approximately 90% and 70% over 2 days in reactors containing stream water and sediment-laden stream water, respectively. / text

Since the earliest explorations of the Colorado Plateau, geologists have suspected that cliffs are retreating back laterally. Clarence Dutton envisioned “the beds thus dissolving edge wise until after the lapse of millions of centuries their terminal cliffs stand a hundred miles or more back from their original position” when he wrote about the landscape in 1882. While many geologic studies have determined how fast rivers cut down through the Plateau, only a few studies have calculated how quickly cliffs retreat laterally, and geologists have been arguing since the 1940’s what exactly drives cliffs to retreat in the first place. We study the Book Cliffs in central Utah, and in particular remnant landforms and deposits related to a 120,000-year history of erosion and deposition, which we date by optically stimulated luminescence methods. Our dataset shows that deposits along the Book Cliffs are preserved especially during times of climate instability, which suggests that escarpment retreat locally is driven by climatic disturbances. This disproves older hypotheses suggesting escarpments retreat in response to local factors regardless of shifts in climate, and it is consistent with the few other well-studied escarpment records globally. We also constrain the rates of cliff retreat via a new measurement approach and luminescence age control, showing that the Book Cliffs have retreated at 1-3 meters per thousand years while local toeslope drainages have incised at about 0.5 meters per thousand years, which confirms that cliffs of shallow-dipping, layered rock retreat laterally faster than streams lower the landscape vertically.

The aim of the study was to investigate the relationship between the glass cliff phenomenon and two forms of sexism: hostile sexism (HS) and benevolent sexism (BS). Glass cliff refers to the tendency to endorse a woman candidate for a normally desirable, high-status position at the time of downfall or when things are not going well. A questionnaire package was first administered to a working people sample (N = 328) with diverse occupational backgrounds. Based on the analyses and findings, to be able to eliminate the potential confounding effect of the order of the scales in the package, the study was repeated on a student sample (N = 147). Finally, analyses were repeated after the data from both samples were combined. Results showed no evidence for 1) the presence of glass cliff and 2) the presence of a relationship between glass cliff and two forms of sexism. The results from both samples were discussed, presenting some plausible explanations for the findings. Limitations of the study and suggestions for future research are also presented.

No description available.

Women face barriers to advancement in male-dominated fields (Glass Ceiling) and in female-dominated fields (Glass Escalator). More research is needed to elucidate the causes of these barriers in order to reduce the negative effects on women’s advancement. This study attempted to broaden the literature through the experimental examination of the glass escalator to further understand the gender inequalities that are seen in female-dominated fields. It employed a factorial design to examine the impact of gender, gender make up of an occupation, and level of authority within that occupation on a supervisor’s evaluation of an employee and decision to offer promotion, mentoring, and increase income and vacation time. Participants were recruited from Amazon Mechanical Turk and were just over half women, predominantly White and heterosexual, had a bachelor’s degree or higher, currently engaged in full-time employment, and half indicated their household income to be between $25,000 and $74,999. Each participant was presented with a single vignette of an employee file who was eligible for a promotion from a female-dominated (nurse), male-dominated (engineer), or gender neutral (accountant) occupation. They evaluated the employee’s performance and made recommendations for promotion, increasing raise and vacation days, and offered mentoring. Participants also completed the Gender Attitude Inventory (GAI; Ashmore, Del Boca, & Bilder, 1995) to better understand the role that gender attitudes play in gender bias in promotion decision-making. Multiple analysis of covariance was utilized to examine main effects and interaction effects of target employee gender, gender-type of occupation, and level of authority of the occupation. Hypotheses that men will be more likely to be promoted into positions with more authority, and women will be viewed as most competent in positions that are female-typed with the least amount of authority were not supported. Results showed that gender attitudes were weakly related to an employee’s performance evaluation, raise, and mentoring. Significant differences were found on the GAI where participants identifying as women, gay, and with a graduate degree had more liberal gender attitudes. Possible explanations for the predominantly insignificant results and future directions are discussed. Suggestions are provided for increasing the strength of the manipulation and factors that possibly decreased the salience of gender. Future experimental and continued qualitative studies in applied settings are recommended to identify causal influences of the glass escalator that examine factors of race, SES, and sexual orientation.

Industrial processes generate large quantities of process and product quality data. Most of this data is stored and is analyzed in a univariate fashion. However important information may be lost through the implementation of univariate analysis methods. This information is contained in the correlation structure amongst the process and product quality variables and between these two types of variables. Through multivariate analysis this information is retained. As a result process evaluation, prediction and monitoring are more effectively performed. Multivariate data analysis techniques were therefore applied to data sets that summarized three of INCO's Copper Cliff smelting and refining processes. In the first instance the analysis of historical data pertaining to a batch leaching process was undertaken and the time required for leaching was predicted. In the second a multivariate soft sensor was developed in order to predict the concentration of nitric oxide contained in the feed gas to the smelter acid plant. The final project involved the analysis and monitoring of a continuous nickel carbonyl process. The resulting models were evaluated and significant variables with respect to the variation in the process and product quality data and the correlation between them were identified. The product quality data was also well predicted using new process data only that was input to the models. Finally new data was input to the models and the process was monitored using a reduced number of latent variables. Contribution plots were used to identify the original variables that contributed most to the observations that exceeded the established control limits. / Thesis / Master of Science (MSc)

In the course of studying the effects of programming in multiple languages, we unearthed troubling trends in SourceForge artifacts. Our initial studies suggest that programming in multiple languages concurrently negatively affects developer productivity. While addressing our initial question of interest, we discovered a pattern of monolithic commits in the SourceForge community. Consequently, we also report on the effects that this pattern of commits can have when using SourceForge as a data-source for temporal analysis of open source projects or for studies of individual developers.