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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

LOCATING HOT SPOTS OF FECAL POLLUTION IN AN URBAN WATERSHED OF CENTRAL KENTUCKY USING <i>BACTEROIDES</i> 16S rRNA MARKERS

Coakley, Tricia L. 01 January 2011 (has links)
The field of molecular fecal source tracking in the water environment has developed rapidly since the first PCR assays for general and host-­‐specific Bacteroides 16s rRNA markers were published. Numerous host-­‐specific molecular markers and PCR assays have been developed, adding greater specificity, sensitivity and quantitative methods to the array of options. The public demand for readying methods for transfer to the commercial lab, so that they may be used to generate data for public utilities, citizen action groups and regulatory agencies, has fueled the development of an entire new research community. These methods, however plentiful, have not found community agreement and there is no consensus concerning the appropriate implementation of molecular fecal source tracking in the field. Some issues plaguing the implementation include imperfect marker specificity, environmental variability, DNA extraction variability, PCR inhibition and high cost of molecular analysis. This thesis presents an approach for locating hot spots of human fecal pollution in an urban watershed by using published methodologies for the collection of molecular fecal source tracking data along with a tiered watershed screening tool for cost reduction and two data normalization techniques which ameliorate several known sources of error and strengthen the efficacy of watershed application.
202

On the Robustness of the Rank-Based CUSUM Chart against Autocorrelation

Hackl, Peter, Maderbacher, Michael January 1999 (has links) (PDF)
Even a modest positive autocorrelation results in a considerable increase in the number of false alarms that are produced when applying a CUSUM chart. Knowledge of the process to be controlled allows for suitable adaptation of the CUSUM procedure. If one has to suspect the normality assumption, nonparametric control procedures such as the rank-based CUSUM chart are a practical alternative. The paper reports the results of a simulation study on the robustness (in terms of sensitivity of the ARL) of the rank-based CUSUM chart against serial correlation of the control variable. The results indicate that the rank-based CUSUM chart is less affected by correlation than the observation-based chart: The rank-based CUSUM chart shows a smaller increase in the number of false alarms and a higher decrease in the ARL in the out-of-control case than the the observation-based chart. (author's abstract) / Series: Forschungsberichte / Institut für Statistik
203

Pinched bellies and a hell of a fight : the battle at Brawner Farm / Battle at Brawner Farm

Gaff, Alan D. January 1980 (has links)
This thesis examined the movements of Rufus King's Federal division during a portion of the Second Manassas Campaign. With an emphasis on the role of John Gibbon's brigade, this study concentrated on the battle fought on the evening of August 28, 1862 near Groveton, Virginia between King's division and two Confederate divisions under Stonewall Jackson. Events leading up to file battle, poor cooperation between the Union generals and the faulty deployment by Jackson were stressed, as was the severity of the fighting.The withdrawal of King's division following the battle was portrayed as an important strategic error which allowed the two wings of the Confederate army to unite the following day. Although the Union troops fought Jackson's larger force to a draw, poor leadership by the Union generals resulted in tide loss of the advantages gained by the fighting. The Battle at Brawner Farm was an important event in the campaign, although it has generally been overlooked by historians.
204

Running for the Cause or Walking the Talk?: The Influence of the Run for the Cure Event on Participants' Health Practices

Moncks, Kathryn 18 December 2013 (has links)
The aim of the research in this thesis was to describe the motivations and health practices of participants in the Victoria Canadian Breast Cancer Foundation Run for the Cure, a mass physical activity charity event, and follow them forward approximately two andeight months post-event. Physical activity events are now established as part of nonprofits' repertoire of fundraising tools. These types of events can serve as a venue for ‘moving people to trial’ as they attract large numbers and foster mid-intensity participation in a non-competitive and fun environment. Understanding participants’ motives for and experiences in fundraising events can help to enhance the event for both the organization and the participant. Participants in this study were recruited through the Canadian Breast Cancer Foundation’s database of registrants in the 2012 Victoria Run for the Cure. Sixty-four participants completed an online survey gathering demographic, motivation, and health information. Subsequently, twenty-four of these individuals agreed to undergo fitness assessments at two and six months post the event, complete physical activity and healthy eating motivation questionnaires and be interviewed. At T1 participants were not meeting physical activity guidelines and heavier than the average resident in the region. Scores from fitness levels were maintained from two months to eight months post-event, but increased levels of intrinsic motivation for physical activity (Z = .047, p < 0.05), and decreased levels of identified motivation for healthy eating (Z = .036, p < .05) were found. When looking at interview data, factors that largely guided initial event participation involved altruism, reciprocity, and self esteem. The fostering of autonomy and competence and providing a sense of belonging as a result of participation, helped to maintain commitment for both event participation and physical activity after the event. This research supports the notion that ‘fun runs’, provide an ideal environment to provide a context for health behaviour change at the population level, when SDT constructs and intrinsic and identified regulation are supported, especially for those not currently meeting health guidelines. The study offers practical and feasible strategies for the CBCF and other similar organizations to enhance its mandate, and to promote health and prevent disease. / Graduate / 0350 / 0523 / kemoncks@uvic.ca
205

Internal Control Quality as an Explanatory Factor of Tax Avoidance

Bauer, Andrew M January 2011 (has links)
Internal control disclosures mandated by section 404 of the Sarbanes-Oxley Act (SOX) are designed to provide information about a firm’s financial reporting quality and in doing so may offer information on firm-specific tax planning activities. Internal control weaknesses disclosed under SOX are frequently related to a firm’s tax function (Ge and McVay, 2005; Gleason, Pincus and Rego, 2010) and thus raise the question of whether or not these frequent problems affect corporate tax avoidance. In this thesis, I test hypotheses that tax-related disclosures, particularly those that contain company-level internal control weaknesses (ICWs), provide information with respect to long-run tax avoidance. Furthermore, I test hypotheses that the combination of internal control quality and aggressive tax avoidance aid in assessing shareholder returns. To conduct these tests, I collect and construct firm-level SOX disclosure data from 2004 to 2006 across 1,286 publicly-owned corporations. I begin with an empirical analysis of the association between tax avoidance and firm-level ICWs and generally find that the presence of tax ICWs and company-level tax ICWs constrain long-run tax avoidance. For firms with low cash constraints however, company-level tax ICWs appear to lead to an increase in tax avoidance. Nevertheless, subsequent analysis of monthly abnormal returns implies that the stock market reacts negatively to the disclosure of company-level tax ICWs, regardless of whether or not tax aggressiveness is also present. This thesis contributes to the literature by documenting the first evidence that internal control disclosures provide information regarding firm-level tax planning. Although the number of internal control weakness disclosures is decreasing over time, the availability of these SOX disclosures represents a previously unavailable opportunity to examine and further understand internal governance mechanisms within the firm and their influence on tax planning. In addition, this thesis further corroborates prior literature that argues for the importance of the pervasiveness of internal control weaknesses by showing that the pervasive, company-level tax internal control weaknesses are associated with tax avoidance and lower shareholder returns. Finally, my dissertation implies that the presence of tax internal control weaknesses constrains tax avoidance and thus a focus on improving internal controls could help improve the tax planning function. However, my firm-level analysis also implies that effective tax planning is a sustainable process and thus a firm and its stakeholders may require several periods before the full benefits of these improvements are realized.
206

Monitoring And Checking Of Discrete Event Simulations

Ulu, Buket 01 January 2003 (has links) (PDF)
Discrete event simulation is a widely used technique for decision support. The results of the simulation must be reliable for critical decision making problems. Therefore, much research has concentrated on the verification and validation of simulations. In this thesis, we apply a well-known dynamic verification technique, assertion checking method, as a validation technique. Our aim is to validate the particular runs of the simulation model, rather than the model itself. As a case study, the operations of a manufacturing cell have been simulated. The cell, which is METUCIM Laboratory at the Mechanical Engineering Department of METU, has a robot and a conveyor to carry the materials, and two machines to manufacture the items, and a quality control to measure the correctness of the manufactured items. This simulation is monitored and checked by using the Monitoring and Checking (MaC) tool, a prototype developed at the University of Pennsylvania. The separation of low-level implementation details (pertaining to the code) from the high-level requirement specifications (pertaining to the simuland) helps keep monitoring and checking the simulations at an abstract level.
207

Longshore Sediment Transport on a Mixed Sand and Gravel Lakeshore

Dawe, Iain Nicholas January 2006 (has links)
This thesis examines the processes of longshore sediment transport in the swash zone of a mixed sand and gravel shoreline, Lake Coleridge, New Zealand. It focuses on the interactions between waves and currents in the swash zone and the resulting sediment transport. No previous study has attempted to concurrently measure wave and current data and longshore sediment transport rates on a mixed sand and gravel lakeshore beach in New Zealand. Many of these beaches, in both the oceanic and lacustrine environments, are in net long-term erosion. It is recognised that longshore sediment transport is a part of this process, but very little knowledge has existed regarding rates of sediment movement and the relationships between waves, currents and swash activity in the foreshore of these beach types. A field programme was designed to measure a comprehensive range of wind, wave, current and morphological variables concurrently with longshore transport. Four electronic instruments were used to measure both waves and currents simultaneously in the offshore, nearshore and swash zone. In the offshore area, an InterOcean S4ADW wave and current meter was installed to record wave height, period, direction and velocity. A WG-30 capacitance wave gauge measured the total water surface variation. A pair of Marsh-McBirney electromagnetic current meters, measuring current directions and velocities were installed in the nearshore and swash zone. Data were sampled for 18 minutes every hour with a Campbell Scientific CR23x data-logger. The wave gauge data was sampled at a rate of 10 Hz (0.1 s) and the two current meters at a rate of 2 Hz (0.5 s). Longshore sediment transport rates were investigated with the use of two traps placed in the nearshore and swash zone to collect sediment transported under wave and swash action. This occurred concurrently with the wave measurements and together yielded over 500 individual hours of high quality time series data. Important new insights were made into lake wave processes in New Zealand's alpine lakes. Measured wave heights averaged 0.20-0.35 m and ranged up to 0.85 m. Wave height was found to be strongly linked to the wind and grew rapidly to increasing wind strength in an exponential fashion. Wave period responded more slowly and required time and distance for the wave length to develop. Overall, there was a narrow band of wave periods with means ranging from 1.43 to 2.33 s. The wave spectrum was found to be more mixed and complicated than had previously been assumed for lake environments. Spectral band width parameters were large, with 95% of the values between 0.75 and 0.90. The wave regime attained the characteristics of a storm wave spectrum. The waves were characteristically steep and capable of obtaining far greater steepness than oceanic wind-waves. Values ranged from 0.010 to 0.074, with an average of 0.051. Waves were able to progress very close to shore without modification and broke in water less than 0.5 m deep. Wave refraction from deep to shallow water only caused wave angles to be altered in the order of 10%. The two main breaker types were spilling and plunging. However, rapid increases in beach slope near the shoreline often caused the waves to plunge immediately landward of the swash zone, leading to a greater proportion of plunging waves. Wave energy attenuation was found to be severe. Measured velocities were some 10 times less at two thirds the water depth beneath the wave. Mean orbital velocities were 0.30 m s⁻¹ in deep water and 0.15 m s⁻¹ in shallow water. The ratio difference between the measured deep water orbital velocities and the nearshore orbital velocities was just under one half (us/uo = 0.58), almost identical to the predicted phase velocity difference by Linear wave theory. In general Linear wave theory was found to provide good approximations of the wave conditions in a small lake environment. The swash zone is an important area of wave dissipation and it defines the limits of sediment transport. The width of the swash zone was found to be controlled by the wave height, which in turn determined the quantity of sediment transported through the swash zone. It ranged in width from 0.05 m to 6.0 m and widened landward in response to increased wave height and lakeward in response the wave length. Slope was found to be an important secondary control on swash zone width. In low energy conditions, swash zone slopes were typically steep. At the onset of wave activity the swash zone becomes scoured by swash activity and the beach slope grades down. An equation was developed, using the wave height and beach slope that provides close estimates of the swash zone width under a wide range of conditions. Run-up heights were calculated using the swash zone width and slope angle. Run-up elevations ranged from 0.01 m to 0.73 m and were strongly related to the wave height and the beach slope. On average, run-up exceeds the deep water wave height by a factor of 1.16H. The highest run-up elevations were found to occur at intermediate slope angles of between 6-8°. Above 8°, the run-up declined in response to beach porosity and lower wave energy conditions. A generalised run-up equation for lake environments has been developed, that takes into account the negative relationship between beach slope and run-up. Swash velocities averaged 0.30 m s⁻¹ but maximum velocities averaged 0.98 m s⁻¹. After wave breaking, swash velocities quickly reduced through dissipation by approximately one half. Swash velocity was strongly linked to wave height and beach slope. Maximum velocities occurred at beach slopes of 5°, where incident swash dominated. At slopes between 6° and 10°, swash velocities were hindered by turbulence, but the relative differences between the swash and backswash flows were negligible. At slope angles above 10° there was a slight asymmetry to the swash/backswash flow velocities due to beach porosity absorbing water at the limits of the swash zone. Three equations were developed for estimating the mean and maximum swash velocity flows. From an analysis of these interactions, a process-response model was developed that formalises the morphodynamic response of the swash zone to wave activity. Longshore sediment transport occurred exclusively in the swash zone, landward of the breaking wave in bedload. The sediments collected in transit were a heterogeneous mix of coarse sands and fine-large gravels. Hourly trapped rates ranged from 0.02 to 214.88 kg hr⁻¹. Numerical methods were developed to convert trapped mass rates in to volumetric rates that use the density and porosity of the sediment. A sediment transport flux curve was developed from measuring the distribution of longshore sediment transport across the swash zone. Using numerical integration, the area under this curve was calculated and an equation written to accurately estimate the total integrated transport rates in the swash zone. The total transport rates ranged from a minimum of 1.10 x 10-5 m³ hr⁻¹ to a maximum of 1.15 m³ hr⁻¹. The mean rate was 7.36 x 10⁻² m³ hr⁻¹. Sediment transport was found to be most strongly controlled by the wave height, period, wave steepness and mean swash velocity. Transport is initiated when waves break at an oblique angle to the shoreline. No relationships could be found between the grain size and transport rates. Instead, the critical threshold velocities of the sediment sizes were almost always exceed in the turbulent conditions under the breaking wave. The highest transport rates were associated with the lowest beach slopes. It was found that this was linked to swash high velocities and wave heights associated with foreshore scouring. An expression was developed to estimate the longshore sediment transport, termed the LEXSED formula, that divides the cube of the wave height and the wave length and multiplies this by the mean swash velocity and the wave approach angle. The expression performs well across a wide range of conditions and the estimates show very good correlations to the empirical data. LEXSED was used to calculate an accurate annual sediment transport budget for the fieldsite beaches. LEXSED was compared to 16 other longshore sediment transport formulas and performed best overall. The underlying principles of the model make its application to other mixed sand and gravel beaches promising.
208

The spatial and temporal variability of nitrate in streams of the Bull Run Watershed, Oregon /

Bakke, Paul D. January 1993 (has links)
Thesis (M.S.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 155-162). Also available on the World Wide Web.
209

Evaluating uncertainty in water resources estimation in southern Africa : a case study of South Africa /

Sawunyama, Tendai January 2008 (has links)
Thesis (Ph.D. (Institute for Water Research)) - Rhodes University, 2009.
210

Making meaning outside of the system a narrative exploration of recovery within a peer-run setting /

Goldsmith, Rachel Edrea Stern. January 2010 (has links)
Title from first page of PDF document. Includes bibliographical references (p. 79-82).

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