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UTeach summer masters statistics course : a journey from traditional to Bayesian analysisFitzpatrick, Daniel Lee 05 January 2011 (has links)
This paper will outline some of the key parts of the Statistics course offered through the UTeach Summer Master’s Program as taught by Dr. Martha K. Smith. The paper begins with the introduction of the normal probability density function and is proven with calculus techniques and Euclidean geometry. Probability is discussed at great length in Smith’s course and the importance of understanding probability in statistical analysis is demonstrated through a reference to a study on how medical doctors confuse false positives in breast cancer testing. The frequentist perspective is concluded with a proof that the normal probability density function is zero.
The shift from traditional to Bayesian inference begins with a brief introduction to the terminology involved, as well as an example with patient testing. The pros and cons of Bayesian inference are discussed and a proof is shown using the normal probability density function in finding a Bayes estimate for µ.
It will be argued that a Statistics course moving from traditional to Bayesian analysis, such as that offered by the UTeach Summer Master’s Program and Smith, would supplement the traditional Statistics course offered at most universities. Such a course would be relevant for the mathematics major, mathematics educator, professionals in the medical industry, and individuals seeking to gain insights into how to understand data sets in new ways. / text
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Mantle heterogeneity and flow from seismic and geodynamic constraintsSimmons, Nathan Alan, 1975- 18 August 2011 (has links)
Not available / text
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Trajectory calculation in an electrostatic positron beam using a reformulated extended charge density model馮德操, Fung, Russell. January 1998 (has links)
published_or_final_version / Physics / Master / Master of Philosophy
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An exploration into acid concentration effects on pKa using density functional theoryShah, Ali Akbar January 2010 (has links)
No description available.
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Gas-Phase Photoelectron Spectroscopy and Computational Studies of [FeFe]-Hydrogenase Inspired-Catalysts for Hydrogen ProductionLockett, Lani Victoria January 2009 (has links)
The work presented in this dissertation focuses on the [FeFe]-hydrogenase active site as inspiration for the design and synthesis of complexes capable of the electrocatalytic generation of molecular hydrogen from protons and electrons. The majority of work discussed uses gas-phase photoelectron spectroscopy (PES) and density functional theory (DFT) to probe and analyze the bonding and electron distribution in potential catalysts. These two techniques are also used to explore the nature of cyanide as a ligand, due to its presence and unknown role in these enzymes. This dissertation begins with the study of (η⁵-C₅H₅)Fe(CO)₂X (FpX) and (η⁵- C₅Me₅)Fe(CO)₂X (Fp*X) complexes where X = H⁻, Cl⁻, and CN⁻ to assess and compare their π-accepting abilities, which is contradicted in the literature. The shifts in ionization energies measured by PES provide a measure of the relative bonding effects. The results indicate cyanide is, overall, a weak π-acceptor, and the σ- and π-donor interactions are important to understanding the chemistry. The molecule [(μ-ortho-C₆H₄S₂)][Fe(CO)₃]₂ was examined, in part due to the delocalized π-orbitals of the C₆H₄S₂ ligand, which could facilitate the redox chemistry necessary for catalysis. Computations show that upon ionization, the complex adopts a semi-bridging carbonyl; termed “rotated structure”. The reorganization energy of this geometry change was determined, which may provide understanding of how the active site in the enzyme enables electron transfer to achieve this catalysis. Next complexes of the form (μ-SCH₂XCH₂S)[Fe(CO)₃]₂, where X=CH₂, O, NH, ᵗBuN, MeN, were explored in order to provide insight to the unknown atom at the central bridging position of the alkyl chain in the [FeFe]-hydrogenase enzyme. The likelihood of a rotated cationic structure is also shown, with reorganization energy values similar to that seen for [(μ-ortho-C₆H₄S₂)][Fe(CO)₃]₂. The final chapter explores the replacement of selenium for sulfur in (μ- X(CH₂)₃X)[Fe(CO)₃]₂ and (μ-X(CH₂)₂CH(CH₃)X)[Fe(CO)₃]₂, where X is either sulfur or selenium. The PES data show destabilization of the selenium complex ionizations compared to the sulfur complexes and a lower reorganization energy was calculated. The computed HOMO-LUMO gap energy for the selenium-based complex is roughly 0.17 eV smaller than for the sulfur analogs, which may indicate a lower reduction potential is needed.
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Property size preferences and the value of private and public outdoor spaces amid a shift to high-density residential development: A case study of Kitchener-Waterloo, OntarioDeFields, Emma January 2013 (has links)
Planning policies in Ontario, such as the Provincial Policy Statement and the Growth Plan for the Greater Golden Horseshoe, enforce urban growth boundaries to preserve natural and agricultural lands while improving neighbourhood and city vibrancy. Consequently, urban areas must be intensified through high-density development, which will limit the land available for public green spaces and large private yards. As a result, homebuyers looking for spacious properties will have to rely mainly on the turnover of older homes. Therefore, this thesis explores how residents currently living in homes with private yards value private and public outdoor space, and whether they have interest in upsizing or downsizing their homes in the future. Neighbourhood and property attributes that may be influential in homebuyer decision-making are also investigated.
The cities of Kitchener and Waterloo (“Kitchener-Waterloo”) were chosen as the study location, as both cities are affected by the Growth Plan and are currently being intensified. From March to August, 2012, a random sample of 1272 households living in homes with private yards were invited to participate in a survey on yard landscaping and maintenance practices and property preferences, after which a total of 206 surveys were analyzed.
Most respondents were living in medium-sized homes with medium-sized yards, and results indicated that homes and yards of medium size would be the most commonly preferred options if residents were to move (considering their household size, health, finances, etc.). On the whole, the target market for high-density homes (i.e. condominiums, small houses, and small yards) came mainly from the aging population. Nevertheless, when asked if they would ever live with less yard space in the future (when their household conditions could differ from what they were at the time of the survey), 58% of all respondents indicated that they may live in a home with a small yard and 41% indicated that they may live with no yard. Such a finding further indicated that residents may find high-density dwellings more appealing as they age.
Based on findings, ways of increasing the appeal of compact dwellings are discussed, such as including a small yard or balcony, providing privacy, ensuring access to public green spaces, and being located in a safe neighbourhood. Landscapes neat in appearance and designed with grass, colourful vegetation, trees, and natural gardens are also expected to increase property appeal.
Overall, if development is to remain restricted to built-up areas, developers and planners will have to create desirable high-density homes located in communities that accommodate the lifestyles of potential residents. This thesis addresses such a challenge by delineating target market groups with the potential to move to high-density homes, and by providing insight into the variables that may increase the appeal of properties as landscapes are intensified.
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Torrefaction Behaviour of Agricultural BiomassSule, Idris 12 September 2012 (has links)
Torrefaction has become a topic of interest in recent times not only because farmers could increase their income due to more farming activities for biomass feedstock demands but also it promotes opportunities for green job creation, provides alternative fuel source for coal fired plants, and contributes to greenhouse gas emission mitigation. Hence, this thesis explored the torrefaction behaviour of both herbaceous (switchgrass, miscanthus, wheat straw) and short rotation (willow) agricultural energy crops in terms of hydrophobicity, grindability and energy density. The lignocellulosic compositions of raw and treated switchgrass and bulk density of raw and treated miscanthus were also determined. Hence, the outcomes of these experimental investigations facilitated the development of a torrefaction definition.
The research also studied the heat transfer mechanisms of torrefaction and developed mathematical models to simulate the heat generation profile due to the internal and spontaneous combustion of a cylindrically-shaped poplar wood. COMSOL modeling software was used to analyze and simulate the heat generation profiles that were closely similar to those from the experiments; hence led to a development of a correction factor to scale treatment inputs. / Thesis / OMAFRA HQP
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Migratory timing, fitness, and behaviour in a Neotropical migrant songbird: insights from long-term data and experimentsMcKellar, ANN 25 September 2012 (has links)
Migratory birds face the distinct challenge of travelling between widely separated and environmentally distinct areas for their breeding and non-breeding periods. They may be faced with different pressures at different points in their life cycle, and a solid understanding of the drivers of individual fitness and population demography is crucial to understanding the ecological and evolutionary trajectories of their populations. In this thesis, I combine long-term data and experimental manipulations to study migratory patterns and arrival dynamics, density dependence, and reproductive behaviour in a long-distance migratory bird, the American redstart.
First, I show that non-breeding season weather is associated with redstart phenology on the breeding grounds. Greater winter rainfall corresponds to earlier arrival and egg-laying dates at both the population and individual level, indicating that individual birds may be able to adjust their phenology in response to conditions in winter. Furthermore, I demonstrate these associations independently at two breeding populations at opposite sides of the redstart breeding range and their corresponding putative non-breeding areas: greater rainfall in Jamaica and Mexico was associated with advanced redstart phenology in Ontario and Alberta, respectively. Second, I performed a manipulation experiment to delay the arrival of male redstarts to the breeding grounds. I show that delayed males suffer reduced fledging success in comparison to early-arriving males that bred early or late, but equivalent success in comparison to males that arrived and bred late. These results provide evidence against the importance of either timing or individual quality, but instead suggest that other aspects of quality, namely mate and territory quality, may be important factors driving the success of early-arriving males. Third, I examine the consequences of density dependence for reproductive success and mating behaviour in a population of redstarts for which I showed density-dependent population growth over a period of 11 years. Greater breeding density, both at an annual scale and at a local scale, was associated with reduced success and greater paternity loss. Overall, my findings contribute to a broader understanding of the selective pressures and regulatory mechanisms acting on migratory birds, from the individual up to the population level. / Thesis (Ph.D, Biology) -- Queen's University, 2012-09-25 13:17:33.172
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An evaluation of the Georgia and Marshall methods of bituminous mix designs: sensitivity to changes in aggregate grading and asphalt contentStapler, William Thomas 08 1900 (has links)
No description available.
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Monitoring environmental features using leaf stomatal characteristicsMetcalfe, Michelle J. January 1997 (has links)
It is recognised that atmospheric CO(_2) concentrations are increasing, with concerns raised as to the global impact continued rises may have. Plant stomatal parameters have been suggested as a means of monitoring changing CO(_2) levels. In order to assess their suitability for use, a thorough examination of leaf characteristics within a variety of surroundings was undertaken. Environments examined included both natural variations in CO(_2), which incorporated a variety of environmental influences and artificially enhanced ones where it was possible to monitor specific responses to variable CO(_2) levels. A short term study of Ranunculus ficaria, Sambucus nigra and Hedera helix revealed considerable variation in stomatal parameters, with inconsistent responses observed between and within species. These variations could not be attributed to CO(_2) changes and were assigned to a combination of other factors. R. ficaria grown in an artificial environment at ambient and elevated CO(_2) produced significant and consistent changes in stomatal parameters. Stomatal density and index were found to be reduced at elevated CO(_2) concentrations, with a decrease in guard cell dimensions. Salix herbacea, growing along a naturally reduced CO(_2) partial pressure gradient further highlighted the extent of variation in stomatal parameters in extant material within a species. No consistent stomatal trends associated with changing CO(_2) levels were observed. This inherent variation must be considered before any conclusions can be made regarding stomatal parameters obtained from fossil material. The novel application of molecular biology techniques to identify S. herbacea leaves was partially successful. However, identification of leaf macrofossils was not possible, due to the inferior preservation of DNA. However, the technique will provide a useful tool for identification if suitably preserved macrofossil fragments were available. S. herbacea leaf macrofossils revealed no consistent correlation to past changes in CO(_2) levels. The use of as an additional tool with which to monitor environmental change once again showed variation, and was not associated closely with changes in CO(_2) levels or stomatal parameters. In light of this work it would appear that the use of stomatal parameters is of limited value as a model to monitor environmental change, in the absence of information concerning other variables, and as such must be treated with caution.
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