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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.
51

College Athletics, Undergraduate Recruitment, and Alumni Giving: A Review of the Evidence

Livingston, Ebony Michelle 01 January 2009 (has links)
There has been a long-standing debate about the role and place of intercollegiate athletics (Schulman & Bowen, 2003). Often the focus is on whether successful athletic programs lead to ?value-added? outcomes such as increased alumni giving (Turner, Meserve & Bowen, 2001; Sperber, 2000), or enhanced student applicant pools (Tucker & Amato, 1993; Toma & Cross, 1998; McCormick & Tinsley, 1987; Murphy & Trandel, 1994). The empirical evidence on these issues is both limited, and mixed. For example, the findings of a few methodologically rigorous studies suggest some value-added ?applicant pool? benefits of successful athletic programs. In contrast, studies directly examining student college preferences have produced mixed results. This study offers a review of the extant empirical research on this topic in order to assess the impact of college athletic reputation on three key outcomes: size of applicant pool; quality of applicant pool; and university giving.
52

Development and Analysis of the Systematically Merged Atlantic Regional Temperature and Salinity (SMARTS) Climatology for Satellite-Derived Ocean Thermal Structure

Meyers, Patrick C. 21 July 2011 (has links)
A new oceanic climatology to calculate ocean heat content (OHC) was developed for application year-round in the Atlantic Ocean basin. The Systematically Merged Atlantic Regional Temperature and Salinity (SMARTS) Climatology blends temperature and salinity fields from the World Ocean Atlas 2001 (WOA) and Generalized Digital Environmental Model v.3.0 (GDEM) at 1/4° resolution. This higher resolution climatology better resolves features in the Gulf of Mexico (GOM), including the Loop Current and eddy structures, than the previous coarser 1/2° products. Daily mean isotherm depths of the 20° C (D20) and 26° C (D26) (and their mean ratio), reduced gravity (e.g., 2-layer model), mixed layer depth (MLD), and OHC were estimated from the blended climatology. Using SMARTS with satellite-derived surface height anomaly and SST fields, daily values of D20, D26, MLD, and OHC were calculated from 1998 to 2010 using a two-layer model approach. Airborne and ship-deployed eXpendable BathyThermographs (XBT), long-term moorings, and Argo profiling floats provided the in-situ data to blend and assess the SMARTS Climatology. A clear, direct relationship emerged from the detailed analysis between satellite-derived and in-situ measurements of isotherm depths and OHC. This new climatological approach created a more accurate estimation of isotherm depths and OHC from satellite radar altimetry measurements, which can be used in hurricane intensity forecasts from the Statistical Hurricane Intensity Prediction Scheme (SHIPS). The Mainelli (2000) technique of calculating OHC was reexamined to most accurately project sea surface height anomalies (SSHA) into changes in depths of D20, D26, and MLD. SSHA surface features were tracked to determine realistic drift velocities ingested into the objective analysis algorithm. The former OHC algorithm assumed a climatological MLD, however observations show large temporal variability of MLD. Using a SSHA-dependent MLD for the OHC estimation improves the two-layer model by 5%. Upper ocean thermal structure estimations improved by 25% using the SMARTS Climatology as compared to that of Mainelli (2000).
53

A Proud Legacy, A New Future: Bringing Ottawa's Growth Management Strategy Into the 21st Century

Heydorn, Christina Anita January 2007 (has links)
As Canada’s capital, the City of Ottawa has benefited from several comprehensive land use planning exercises since the early 1900s. Early plans carried out by the federal government were led by Prime Ministers who, in wanting to beautify the region, initiated long range plans that spanned both sides of the Ottawa River, providing land use goals and guidance for what are today the cities of Ottawa and Gatineau. The planning context changed through the 1970s, however. The federal government played a lesser role in land use planning as regional and area municipal governments grew and an expanding technically trained staff developed local plans. It was in the absence of a strong regional plan aimed at controlling outward expansion that there was rapid growth of low density suburban communities outside of the National Capital Commission greenbelt. Today, planning policy in Ottawa recognizes the environmental, social, and economic benefits of compact development and encourages by, in part, directing growth to the existing built-up area. Unfortunately, residential intensification efforts in the City have been disappointing. While the City has developed a variety of policies and programs to encourage and support residential intensification, it appears site level constraints have prohibited it to occur in a significant way. This research is concerned with identifying weaknesses in the City of Ottawa’s current growth management strategy. The purpose of this research is to provide recommendations that can be used to strengthen Ottawa’s growth management policies and programs to more effectively achieve the compact urban form desired by the municipality. The findings demonstrate that there is some level of disconnect between what recent literature and key informant interviews identify as the barriers to residential intensification at the site level and the motherhood principles for compact development at the municipal level. More specifically, barriers can be summarized as community and political resistance, regulatory challenges, and policy vs. market realities. It is recommended that the City of Ottawa adopt a strengthened strategy that establishes achievable growth and intensification targets; encourages community support for compact development; considers growth over the longer term and with a regional perspective; and is advocated by strong leaders. Only in this way can the City create an improved strategy that will, like earlier plans, make Ottawa once again a proud leader in urban planning efforts in Canada.
54

Suburban Intensification: cultivating place in the dispersed city

Gould, Kathryn January 2009 (has links)
The sustainable growth and development of our cities are amongst the most important issues of the world today. It is estimated that soon up to ninety percent of the world’s population will live in urban centers. How to accommodate such growth, while maintaining high quality of life, is one of the most challenging tasks facing society. The design proposal will address the future population growth in the City of Toronto with the intensification of an inner suburban area in central Etobicoke. It is founded on principles that address the communities growing needs while working to cultivate a sense of place and improve the livability of the surrounding neighbourhood. Within this area through the design of a mixed-use development with significant forms of public space and amenities, the neighbourhood would experience increased connectivity with the surrounding environment and improved sense of community. It will draw together the residents of the area and cultivate a new public realm from its now disparate elements, this would raise the areas ability to meet future housing needs and mitigate congestion. The design for the Etobicoke Centre is a symptom of – and a drive toward – the evolution of a mature suburb to a place aspiring for urbanity. The story of suburban transformation is relevant to metropolitan areas around the continent, and the clarity of the architectural design demonstrates how good public space design can set standards of sophistication, craft, and structure for other developments to follow. New growth in the area has the potential to act as a catalyst for change, demonstrating how existing inner suburbs have the ability to evolve into more urban, sustainable places.
55

A Proud Legacy, A New Future: Bringing Ottawa's Growth Management Strategy Into the 21st Century

Heydorn, Christina Anita January 2007 (has links)
As Canada’s capital, the City of Ottawa has benefited from several comprehensive land use planning exercises since the early 1900s. Early plans carried out by the federal government were led by Prime Ministers who, in wanting to beautify the region, initiated long range plans that spanned both sides of the Ottawa River, providing land use goals and guidance for what are today the cities of Ottawa and Gatineau. The planning context changed through the 1970s, however. The federal government played a lesser role in land use planning as regional and area municipal governments grew and an expanding technically trained staff developed local plans. It was in the absence of a strong regional plan aimed at controlling outward expansion that there was rapid growth of low density suburban communities outside of the National Capital Commission greenbelt. Today, planning policy in Ottawa recognizes the environmental, social, and economic benefits of compact development and encourages by, in part, directing growth to the existing built-up area. Unfortunately, residential intensification efforts in the City have been disappointing. While the City has developed a variety of policies and programs to encourage and support residential intensification, it appears site level constraints have prohibited it to occur in a significant way. This research is concerned with identifying weaknesses in the City of Ottawa’s current growth management strategy. The purpose of this research is to provide recommendations that can be used to strengthen Ottawa’s growth management policies and programs to more effectively achieve the compact urban form desired by the municipality. The findings demonstrate that there is some level of disconnect between what recent literature and key informant interviews identify as the barriers to residential intensification at the site level and the motherhood principles for compact development at the municipal level. More specifically, barriers can be summarized as community and political resistance, regulatory challenges, and policy vs. market realities. It is recommended that the City of Ottawa adopt a strengthened strategy that establishes achievable growth and intensification targets; encourages community support for compact development; considers growth over the longer term and with a regional perspective; and is advocated by strong leaders. Only in this way can the City create an improved strategy that will, like earlier plans, make Ottawa once again a proud leader in urban planning efforts in Canada.
56

Suburban Intensification: cultivating place in the dispersed city

Gould, Kathryn January 2009 (has links)
The sustainable growth and development of our cities are amongst the most important issues of the world today. It is estimated that soon up to ninety percent of the world’s population will live in urban centers. How to accommodate such growth, while maintaining high quality of life, is one of the most challenging tasks facing society. The design proposal will address the future population growth in the City of Toronto with the intensification of an inner suburban area in central Etobicoke. It is founded on principles that address the communities growing needs while working to cultivate a sense of place and improve the livability of the surrounding neighbourhood. Within this area through the design of a mixed-use development with significant forms of public space and amenities, the neighbourhood would experience increased connectivity with the surrounding environment and improved sense of community. It will draw together the residents of the area and cultivate a new public realm from its now disparate elements, this would raise the areas ability to meet future housing needs and mitigate congestion. The design for the Etobicoke Centre is a symptom of – and a drive toward – the evolution of a mature suburb to a place aspiring for urbanity. The story of suburban transformation is relevant to metropolitan areas around the continent, and the clarity of the architectural design demonstrates how good public space design can set standards of sophistication, craft, and structure for other developments to follow. New growth in the area has the potential to act as a catalyst for change, demonstrating how existing inner suburbs have the ability to evolve into more urban, sustainable places.
57

A novel approach to process debottlenecking and intensification: integrated techniques for targeting and design

Al Thubaiti, Musaed Muhammad 15 May 2009 (has links)
Continuous process improvement is a critical element in maintaining competitiveness of the process industries. An important category of process improvement is process debottlenecking which is associated with plants that have sold-out products while making a profit. In such cases, market conditions and the prospects for enhancing revenues and profits drive the process to increase production. To overcome the limitation of conventional sequential unit-by-unit debottlenecking approach, this work introduces a new approach. This new approach is simultaneous in nature and is based on posing the debottlenecking task as a process integration task which links all the design and operating degrees of freedom and exploits synergies among the units and streams to attain maximum debottlenecking. Additionally, this new approach considers heat integration of the process while simultaneously performing the debottlenecking. Because of the general nonconvexity of the process model, a rigorous interval-based bounding technique is used to determine the target for maximum extent of debottlenecking aside from the problem nonconvexity. Inclusion isotonicity using interval arithmetic is used to determine a global bound for the maximum extent of process debottlenecking. Focus is given to no/low cost debottlenecking such as modest changes in design and operating degrees of freedom. Two case studies are solved to illustrate the applicability of the new approach and its superior results compared to the conventional sequential approach. Intensification, to debottleneck a process and to improve process safety is also addressed in this work. A new definition and classification of intensification is introduced. This classification distinguishes between two types of intensification: single unit and whole process. Process integration and optimization techniques are used to develop a systematic procedure for process intensification. Focus is given to the interaction among the process units while enhancing the intensification of the process. A case study is solved to illustrate the usefulness of the developed approach.
58

Modeling, image processing and attitude estimation of high speed star sensors

Katake, Anup Bharat 15 May 2009 (has links)
Attitude estimation and angular velocity estimation are the most critical components of a spacecraft's guidance, navigation and control. Usually, an array of tightlycoupled sensors (star trackers, gyroscopes, sun sensors, magnetometers) is used to estimate these quantities. The cost (financial, mass, power, time, human resources) for the integration of these separate sub-systems is a major deterrent towards realizing the goal of smaller, cheaper and faster to launch spacecrafts/satellites. In this work, we present a novel stellar imaging system that is capable of estimating attitude and angular velocities at true update rates of greater than 100Hz, thereby eliminating the need for a separate star tracker and gyroscope sub-systems. High image acquisition rates necessitate short integration times and large optical apertures, thereby adding mass and volume to the sensor. The proposed high speed sensor overcomes these difficulties by employing light amplification technologies coupled with fiber optics. To better understand the performance of the sensor, an electro-optical model of the sensor system is developed which is then used to design a high-fidelity night sky image simulator. Novel star position estimation algorithms based on a two-dimensional Gaussian fitting to the star pixel intensity profiles are then presented. These algorithms are non-iterative, perform local background estimation in the vicinity of the star and lead to significant improvements in the star centroid determination. Further, a new attitude determination algorithm is developed that uses the inter-star angles of the identified stars as constraints to recompute the body measured vectors and provide a higher accuracy estimate of the attitude as compared to existing methods. The spectral response of the sensor is then used to develop a star catalog generation method that results in a compact on-board star catalog. Finally, the use of a fiber optic faceplate is proposed as an additional means of stray light mitigation for the system. This dissertation serves to validate the conceptual design of the high update rate star sensor through analysis, hardware design, algorithm development and experimental testing.
59

The ecology of freshwater communities of stock water races on the Canterbury Plains

Sinton, Amber January 2008 (has links)
Agricultural intensification on the Canterbury Plains in New Zealand has lead to the degradation of natural streams and rivers through lowering of water quality and significant reduction of surface flows from the use of ground and surface water resources. However, this same agricultural expansion has led to the development of a network of permanently flowing open water races to supply stock water to farms across the Canterbury Plains. Stock water races form an extensive network, with approximately 6,500 km of races. Initially I surveyed 62 water races and compared habitat characteristics, water quality, benthic invertebrate and fish communities with nearby natural streams. Races are characterised physically by straight, narrow and shallow channels, and small, uniform substrate. Water races are more turbid than natural streams, and can have high summer temperatures. The benthic macroinvertebrate communities of water races contained a range of taxa, including some not found in natural streams, but communities were less diverse than communities in natural streams, and tended to be dominated by a limited set of generalist taxa. A longitudinal study of three water races showed gradients in physical characteristics of races, including a downstream decrease in channel width, water depth, current velocity and substrate size. However, few strong longitudinal changes to community structure were found, as the generalist taxa commonly occurring in water races were able to tolerate conditions throughout the race network. To test if macroinvertebrate communities were limited by the homogeneous habitat of water races, I conducted a substrate manipulation experiment, where large cobbles and small boulders were added to reaches in five water races. Despite an increase in substrate and current heterogeneity, there were few significant changes to the macroinvertebrate communities over the four months of the manipulation. This outcome does not eliminate low habitat heterogeneity as a limiting factor for water race communities. Rather, the benthic invertebrate community throughout the water race network is a product of the homogeneous habitat, which limits the availability of colonists of taxa that would benefit from increased habitat diversity. A survey of the fish assemblages of water races found races had a depauperate fish community. Only two species were commonly found in water races, and the average species richness of races was 1.5. By contrast natural streams had a higher diversity of fish species (mean 4 three species), and contained representatives of a greater number of species that are typical of streams and rivers on the Canterbury Plains. My research has shown that stock water races provide an important source of aquatic biodiversity on the plains, both in addition to natural streams and in their own right. However, the biodiversity value of stock water races could be improved with enhancement of in-stream habitat.
60

Strategies for sustainable livestock production in Brazil and the European Union

zu Ermgassen, Erasmus Klaus Helge Justus January 2018 (has links)
Livestock provide as much as one-third of all protein consumed by humans, but have a disproportionate and growing environmental impact. Livestock production occupies 50-75% of agricultural land, contributes 15% of anthropogenic greenhouse gas emissions, and drives agricultural expansion in the tropics through the global trade in animal feed. This thesis therefore evaluates two strategies for shrinking the environmental impact of the livestock sector. First, I evaluate the potential for food losses (i.e. foods which were intended for human consumption, but which ultimately are not directly eaten by people) to replace grain- and soybean-based pig feeds in Europe. While food losses have been included in animal feed for millennia, the practice is all but banned in the European Union, because of disease control concerns. Several East Asian states have in the last 20 years, however, introduced regulated systems for safely recycling food losses into animal feed. I combine data from multiple sources (including government reports, the animal science literature, and factory-floor data from South Korean swill-feed factories), and find that the introduction of East Asian practices for recycling food losses as animal feed could reduce the land use of EU pork (20% of world production) by one fifth, potentially saving 1.8 million hectares of agricultural land. This would also reduce 12/14 other assessed environmental impacts and deliver economic savings for pig farmers, as swill (cooked food losses) costs 40-60% less than conventional grain-based feeds. In a survey of pig farmers (n=82) and other agricultural stakeholders (n=81) at a UK agricultural trade fair, we found high support (>75%) for the relegalisation of swill. Support for swill feeding arose in part because respondents thought that swill would lower costs, increase profitability, and be better for the environment. Our results also confirmed the critical importance of disease control and consumer communication when considering relegalisation, as respondents who thought that swill would increase disease risks and be unpalatable to consumers were less supportive of relegalisation. Any new system for the use of swill will require careful design of regulation to ensure that heat-treatment is sufficient, and to reduce to a negligible level the risk of uncooked animal by-products entering feed. Our results suggest, however, that if such a system can be established, there would be multiple benefits and widespread support for its relegalisation. Second, I evaluated the potential to increase the productivity of cattle ranching in the Brazilian Amazon. While high hopes have been placed on the potential for intensification of low-productivity cattle ranching to spare land for other agricultural uses, cattle productivity in the Amazon biome (29% of the Brazilian cattle herd) remains stubbornly low, and it is not clear how to realize theoretical productivity gains in practice. I therefore (a) surveyed six on-the-ground initiatives which have been working with local farmers to improve cattle ranching, quantifying their farm practices, animal performance, and economic results; and (b) analysed the progress that has already been made in reconciling agriculture and forest conservation, by evaluating the impact of the flagship anti-deforestation policy, the priority list (Municípios Prioritários). The survey showed that cattle intensification initiatives operating in four states have used a wide range of technologies to improve productivity by 30-490%, while supporting compliance with the Brazilian Forest Code. Using two complementary difference-in-difference estimators, I then found no evidence for trade-offs between agriculture and forest conservation under the priority list; instead, reductions in deforestation in priority list municipalities were paired with increases in cattle production and productivity (cattle/hectare). The policy had no effect on dairy or crop production. Together, these results provide real-world evidence that increases in cattle production in Brazil do not need to come at the expense of the country’s remaining native vegetation.

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