The interaction of a rectangular turbulent jet with a free surface for three jet-exit aspect ratios is experimentally investigated using Particle Image Velocimetry (PIV). The jet exits from a sharp edged rectangular orifice plate, parallel to the free surface and has a jet width of d = 10 mm. Aspect ratios of 1, 2 and 4 are studied with a fixed offset of 3d from the free surface. Reynolds and Froude numbers based on the bulk velocity are 6900 and 1.27 respectively. Detailed 2-D velocity fields are captured using the PIV in the central x-y plane for 0 < x/d < 23.5. The distribution of Reynolds shear stresses and turbulent kinetic energy show that they are suppressed in the vicinity of the free surface due to confinement. There was a significant effect of nozzle geometry on the reattachment point and recirculation region of the jets. / May 2016

No description available.

No description available.

This thesis focused on the fate of nitrogen and trace metals species from combustion and gasification of biomass. The effect of process parameters on the release of these species during pilot-scale combustion and gasification of biomass was investigated and the information used to identify methods for the reduction of these species. The investigation focused on Miscanthus and Dried distillers’ grains with solubles (DDGS). The pilot-scale test rigs used were a fluidised-bed combustor and a fixed-bed downdraft gasifier. The two fuels were analysed by means of proximate, ultimate and ash analysis. The process parameters monitored were temperatures, gas flow, gas composition and ash composition and the process parameters studied are bed temperature and equivalence ratio. The different nitrogen content of the two fuels plays an important role in the emission. Both bed temperature and air to fuel ratio have demonstrated to have an important influence in the release of nitrogen oxides in combustion and ammonia in gasification, therefore they can be used to mitigate the emission of these species in the flue gas. Both processes are affected by the high alkali metals content of the fuels for the tendency to form low melting composites. Differences have been highlighted in the metal distribution between combustion and gasification. The different nitrogen and ash content of the two fuels make the results of the present thesis applicable to predict the behaviour of other biomass fuels according to the fuel characteristics. The scale of the tests performed allowed highlighting which methods can be used to control the emission of nitrogen and trace metal species. Moreover, the investigation highlighted major drawbacks in the use of biomass fuels in both fluidised bed and fixed bed technology due to ash properties.

Class of 2010 Abstract / OBJECTIVES: The purpose of this study was to demonstrate that an increase in INR is associated with a hemorrhagic event in patients taking the oral anticoagulant warfarin. METHODS: A retrospective review of data from 18 patients previously stable on warfarin therapy with an elevation in INR at the time of a hemorrhagic event. Patients were receiving warfarin treatment in the anticoagulation clinic at the Southern Arizona VA Healthcare system from April 2008 to December 2009. Primary outcome measures included a comparison of INR, warfarin dose, and hematocrit at baseline, within 7 days of the event, and during follow-­‐up. RESULTS: A significant increase in INR was observed from baseline to the event (2.5 +/-­‐ 0.36 vs 6.2 +/-­‐ 3.2; p = 0.0002) but differences in INR during all periods of follow-­‐up did not differ from baseline (p = 0.35 – 0.99). When compared with baseline, differences in warfarin dose reached statistical significance when all 12 weeks of follow-­‐up were included (34.4 +/-­‐ 13.8 mg vs 32.4+/-­‐ 15.5 mg; p = 0.01) but were not significant when only the last 8 weeks (p = 0.06) or 4 weeks (p = 0.16) were included. Hematocrit values decreased significantly following hemorrhage (39.8 +/-­‐ 3.63 vs 33.5 +/-­‐ 5.72; p = 0.0002) before trending toward baseline (39.85 +/-­‐ 3.63 vs 37.13 +/-­‐ 4.72; p = 0.007). CONCLUSIONS: Hemorrhagic events were associated with an increased INR in previously stable warfarin patients. The mean weekly warfarin dose required to maintain a therapeutic INR returned to baseline within 8 weeks of the hemorrhagic event.

Solving proportion problems in schools is a very difficult task for most children. Too often children are taught to use techniques for solving fractions when working with ratio and proportion problems. Although these techniques may prove useful for obtaining a solution to a proportion problem, they do not provide rich learning opportunities for students to construct proportional relationships. Individual interviews, problem solving episodes, and personal journals were the primary tools used in collecting data for this study. The problem solving episodes became the key components in observing and interacting with the participants as they solved ratio and proportion problems. The researcher found that individuals must have many elaborated constructions to solve proportion tasks. Without these elaborated constructions the individual is unable to effectively coordinate the information needed to solve proportion tasks. That is, the individual is unable to reason proportionally. Another outcome of this study was the importance of finding meaningful and doable proportion tasks for the informants to complete. Unexpected outcomes of the study included the effect of engaging in problem solving on the identity of the child and the role of language in giving meaning to the tasks. / Typescript. / "Summer Semester, 1992." / "Submitted to the Department of Curriculum and Instruction in partial fulfillment of the requirements for the degree of Doctor of Philosophy." / Advisor: Grayson H. Wheatley, Professor Directing Dissertation. / Includes bibliographical references.

The reproductive behavior of migratory organisms is difficult to characterize as the mating behavior can be difficult to observe. For some species, one sex can be readily observable, but the other may remain hidden, confounding attempts to assess population demographics. For such species, it can be difficult to determine the sex ratio of the population. Without accurate accounts of the numbers of males and females, conservation methods may be insufficient and their performance unclear. Alternative methods of measuring sex ratios therefore must be used to estimate the number of individuals and assess breeding behavior. Here I identified breeding sex ratios (BSR) measured using paternity analysis of offspring through exclusion analysis to quantify the numbers of males contributing. Here I discuss the mating behavior of three species of marine turtle that nest in southern Florida: the loggerhead (Caretta caretta), the leatherback (Dermochelys coriacea), and the green sea turtle (Chelonia mydas) at three beaches (Boca Raton, Juno Beach, and Sanibel Island) from 2013-2017; over 400 nesting females were identified and genotyped and almost 7,000 hatchlings were collected and genotyped. Females from all three species successfully mated with more than one male in all years analyzed demonstrating multiple paternity of clutches. For loggerheads, many male genotypes were identified, suggesting that females likely mate en route to their nesting grounds, inducing a male-biased BSR. Examination of females that were sampled more than once per season (repeats), evidence of sperm storage was found for all nests and some turtles might mate in between nesting events. Leatherback females displayed a higher rate of multiple paternity than was previously published for other Caribbean nesting sites; I hypothesize that this result may be due to a mainland nesting beach effect. The leatherback BSR over all years was approximately 1:1, and one male was identified fathering than two different females’ nests (polygyny). For green turtles, multiple paternity was found and there was evidence of polygyny. Across all three species, evidence for indirect benefits of mating multiply (hatching success or larger hatchlings) was weak or not supported. Together, the four studies contribute to the overall body of reproductive behavior studies. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Tese de mestrado. Mestrado Integrado em Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 2012

Animals performing on simple fixed-ratio (FR) schedules vi typically pause after reinforcement delivery. The present study demonstrated systematic control of pause length in multiple fixed ratio schedules by manipulating FR size and reinforcement magnitude. In Experiment I, two adult male rabbits were stabilized on an alternating, two component, multiple FR 10 FR 10 schedule. Different colored lights were correlated with both FR components. Stability was determined and mean pause lengths were calculated as one FR component was increased in size until the schedule was FR 10 FR 50. Pausing was longer before the large FR component and was positively correlated with increases in FR size. Schedule and stimulus control were demonstrated by randomizing the order of FR presentations and by reversing the colored lights previously correlated with either the small or large FR components. Existing pause differentials were not disrupted under the light reversal or random conditions. In Experiment II, the same rabbits were stabilized at mult FR 10 FR 30 with 1/2 cc of water delivered after each component. In subsequent conditions the magnitude of reinforcement (cc's of water) delivered at the completion of the large FR component, was systematically shifted from 4 cc, to 3 cc, 2 cc, 1 cc and finally back to 1/2 cc. Pausing before the large FR was found to be inversely related to the magnitude of reinforcement delivered in that component. Clearly the animals in this experiment discriminated upcoming schedule conditions and paused relative to FR size and reinforcement magnitude. Hence, it is proper to point out that the term "post-reinforcement pause" is a misnomer since it incorrectly implies a functional relation between pause length and prior schedule conditions.

University of Technology, Sydney. Faculty of Business. / Recent regulatory changes in developed economies have sought to apply uniform standards for corporate governance following a series of high profile corporate collapses between 2000 and 2002. The various regulatory responses raised questions in the governance literature on the appropriateness of a “one size fits all” approach. However, empirical outcomes in this literature do not provide a consistent picture on how, or even whether, governance choices vary with firm characteristics. This thesis addresses the lack in empirical direction by investigating the discriminatory power of a fundamental firm variable, the price-to-book ratio (P/B), that is often applied in Australian and other studies to predict governance outcomes. It evaluates how a joint price-to-book, price-to- earnings, firm classification (P/B, P/E) captures variations in governance choices by Australian firms and compares the results with those using a conventional P/B classification. Choices for two key mechanisms – the level of independence of the board of directors and the quality of its external auditors, are examined as they feature prominently in regulatory reforms. The results show that a joint P/B, P/E classification captures significant differences in the use of both mechanisms confirming that governance frameworks vary with firm characteristics. Consistent with expectations, these differences are recorded for board independence within high and within low P/B firms. Significant variations are also identified in the choice of auditor quality within both P/B classes of firms. By enabling a more parsimonious analysis of firm characteristics through the joint P/B, P/E framework, these results enhance our understanding of the choice of independent directors and high quality auditors. They also lend support to the general proposition that a “one size fits all” governance framework could lead to unnecessary costs for firms as they seek optimal governance arrangements that suit their specific information environments.