Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 120-131). Also available in print.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 85-110.

Thesis (Ph.D.) - University of St Andrews, February 2010.

The problem of this study was to compare performances of college students given relaxation instructions and those not given those instructions on a paired-associate learning task. The results indicated that relaxation instructions alone produced a decrement in recall. When subjects received relaxation instructions as well as the suggestion that relaxation enhances learning, the decrement did not occur. Thus, situational demand characteristics appeared to be a significant variable in determining what effect relaxation instructions had on recall.

Decision makers have long relied on experts to inform their decision making. Expert judgment analysis is a way to elicit and combine the opinions of a group of experts to facilitate decision making. The use of expert judgment is most appropriate when there is a lack of data for obtaining reasonable statistical results. The experts are asked for advice by one or more decision makers who face a specific real decision problem. The decision makers are outside the group of experts and are jointly responsible and accountable for the decision and committed to finding solutions that everyone can live with. The emphasis is on the decision makers learning from the experts. The focus of this thesis is an overview and comparison of the various elicitation and combination methods available. These include the traditional committee method, the Delphi method, the paired comparisons method, the negative exponential model, Cooke’s classical model, the histogram technique, using the Dirichlet distribution in the case of a set of uncertain proportions which must sum to one, and the employment of overfitting. The supra Bayes approach, the determination of weights for the experts, and combining the opinions of experts where each opinion is associated with a confidence level that represents the expert’s conviction of his own judgment are also considered.

Few studies have systematically evaluated whether preferences can reliably be identified using brief procedures. Typically, studies have used brief procedures to select potential reinforcers for use in intervention procedures. A total of 17 food and leisure paired-choice preference assessments were administered to 10 subjects in order to evaluate the extent to which the results of a brief (i.e., single-session) assessment correspond with those from more extended procedures (i.e., 5 sessions). Eleven out of the 17 brief and extended assessments identified the same stimulus as the most preferred (highest rank). Outcomes suggest that a brief assessment can be useful when a single, potent reinforcing stimulus is desired, and an extended assessment should be conducted when a larger number of preferred stimuli is desired.

This study evaluated four lactic streptococcal pairs which had been used routinely in cheese plants to determine (1) if strain growth interactions would produce stimulated growth and acid production; (2) final percent strain ratios and generation times after 1/1 initial inocula volumes and (3) whether final strain ratios could be controlled through adjustment of initial inocula volumes. Strains were propagated in fortified and unmodified whey substrate under pH control at 27C for 12 hours. Cell number and acid activity were evaluated on single and paired strains. Phage typing was used to determine generation times and the percent of each strain in a pair. Cell number increase was found in two of the four pairs grown in the unmodified whey substrate but in only one of the four pairs grown in the fortified medium. Acid production increase was observed in one pair when grown in the unmodified whey substrate, and in one other pair when grown in the fortified medium. Final strain percent ratios of the two of the four pairs (with initial inocula of a 1/1, v/v, ratio), demonstrated unbalanced growth, with one strain accounting for 76 to 92% of the final flora. Generation times of the dominant strain varied significantly with incocula ratios. Increasing the inocula volume ratio of the dominated strain of one pair from 1/1 to 19/1 dropped the final percent of the dominant strain from an average value of 83 to 66%. The dominant organism of this pair increased its doubling time when the inocula ratio was varied from 3/1 to 19/1 (dominated/dominant).

No description available.

Many zeolites are deployed in various industrial processes owing to their robust catalytic performance and hydrothermal stability. Reactions in zeolites are catalyzed via framework aluminum. The Si/Al ratio is a metric that describes the relative aluminum content in zeolites. However, several researchers noted that the proximity of aluminum in the framework could impact the catalyst output [1–3]. In this work, the influence of paired acid sites is examined in ZSM-22. The 1-dimensional nature of ZSM-22 allows for direct assessment of aluminum proximity without the influence of channel intersection. Theoretical investigations via static density functional theory (DFT) optimization calculations on isolated and paired BAS in ZSM-22 revealed a potential increase in deprotonation potential energy (DPE), indicating a weaker acid with closer aluminum sites. One specific paired model, however, suggested stronger acid behavior, likely due to unfavorable proton-proton interactions influenced by proximity and orientation. Additionally, ammonia adsorption calculations inferred improved adsorption by isolated models, possibly due to unfavorable ammonium-proton interactions in the paired models. Reaction state calculations of ethylene and propylene oligomerization suggested enhanced stabilization of reactant molecules in paired sites. The synthesis of ZSM-22 showed sensitivity to precursor ratios and conditions, but pure samples were successfully achieved through iterative optimization. Catalytic testing of ethylene oligomerization with these samples, classified by their Si/Al ratios and unique fractions of paired acid sites, showed a correlation between higher fractions of paired BAS and increased catalytic activity and selectivity. Samples with higher fractions of paired BAS displayed a higher activity and selectivity for heavier hydrocarbons, explained by the enhanced adsorption capacity of paired BAS for larger reactant molecules, prompting further oligomerization and enhanced catalytic activity. Our findings demonstrate the impact of BAS proximity in dictating the activity and selectivity in ZSM-22 and provide valuable insights for designing more efficient industrial zeolite-based catalysts.

The currently available distribution-free confidence interval for a difference of medians in a within-subjects design requires an unrealistic assumption of identical distribution shapes. A confidence interval for a general linear function of medians is proposed for within-subjects designs that do not assume identical distribution shapes. The proposed method can be combined with a method for linear functions of independent medians to provide a confidence interval for a linear function of medians in mixed designs. Simulation results show that the proposed methods have good small-sample properties under a wide range of conditions. The proposed methods are illustrated with examples, and R functions that implement the new methods are provided.