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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.
131

Inuit television broadcasting : cultural identity and expression in a new medium

Cranston, Paul. January 1984 (has links)
No description available.
132

Inuit television broadcasting : cultural identity and expression in a new medium

Cranston, Paul. January 1984 (has links)
No description available.
133

On the Field of Values of the Inverse of a Matrix

Zachlin, Paul Francis 08 June 2007 (has links)
No description available.
134

Poverty and Place in the Context of the American South

Baker, Regina Smalls January 2015 (has links)
<p>In the United States, poverty has been historically higher and disproportionately concentrated in the American South. Despite this fact, much of the conventional poverty literature in the United States has focused on urban poverty in cities, particularly in the Northeast and Midwest. Relatively less American poverty research has focused on the enduring economic distress in the South, which Wimberley (2008:899) calls “a neglected regional crisis of historic and contemporary urgency.” Accordingly, this dissertation contributes to the inequality literature by focusing much needed attention on poverty in the South. </p><p>Each empirical chapter focuses on a different aspect of poverty in the South. Chapter 2 examines why poverty is higher in the South relative to the Non-South. Chapter 3 focuses on poverty predictors within the South and whether there are differences in the sub-regions of the Deep South and Peripheral South. These two chapters compare the roles of family demography, economic structure, racial/ethnic composition and heterogeneity, and power resources in shaping poverty. Chapter 4 examines whether poverty in the South has been shaped by historical racial regimes.</p><p>The Luxembourg Income Study (LIS) United States datasets (2000, 2004, 2007, 2010, and 2013) (derived from the U.S. Census Current Population Survey (CPS) Annual Social and Economic Supplement) provide all the individual-level data for this study. The LIS sample of 745,135 individuals is nested in rich economic, political, and racial state-level data compiled from multiple sources (e.g. U.S. Census Bureau, U.S. Department of Agriculture, University of Kentucky Center for Poverty Research, etc.). Analyses involve a combination of techniques including linear probability regression models to predict poverty and binary decomposition of poverty differences. </p><p>Chapter 2 results suggest that power resources, followed by economic structure, are most important in explaining the higher poverty in the South. This underscores the salience of political and economic contexts in shaping poverty across place. Chapter 3 results indicate that individual-level economic factors are the largest predictors of poverty within the South, and even more so in the Deep South. Moreover, divergent results between the South, Deep South, and Peripheral South illustrate how the impact of poverty predictors can vary in different contexts. Chapter 4 results show significant bivariate associations between historical race regimes and poverty among Southern states, although regression models fail to yield significant effects. Conversely, historical race regimes do have a small, but significant effect in explaining the Black-White poverty gap. Results also suggest that employment and education are key to understanding poverty among Blacks and the Black-White poverty gap. Collectively, these chapters underscore why place is so important for understanding poverty and inequality. They also illustrate the salience of micro and macro characteristics of place for helping create, maintain, and reproduce systems of inequality across place.</p> / Dissertation
135

Mission design concepts for repeat groundtrack orbits and application to the ICESat mission

Pie, Nadege 27 January 2010 (has links)
The primary objective of the NASA sponsored ICESat mission is to study the short and long term changes in the ice mass in the Greenland and Antarctica regions. The satellite was therefore placed into a frozen near-polar near-circular repeat groundtrack to ensure an adequate coverage of the polar regions while keeping the groundtrack periodic and reducing the variations in the orbital elements, and more specifically the semi-major axis of the ICESat orbit. After launch, a contingency plan had to be devised to compensate for a laser that dangerously compromised the lifetime of the ICESat mission. This new plan makes an intensive use of the ICESat subcycles, a characteristic of the repeat groundtrack orbits often over-looked. The subcycle of a repeat groundtrack orbit provide global coverage within a time shorter than the groundtrack repetition period. For a satellite with an off-nadir pointing capacity, the subcycles provide near-repeat tracks which represents added opportunity for altimetry measurement over a specific track. The ICESat subcycles were also used in a very innovative fashion to reposition the satellite within its repeat cycle via orbital maneuvers called phasing maneuver. The necessary theoretical framework is provided for the subcycle analysis and the implementation of phasing maneuvers for any future repeat orbit mission. In the perspective of performing cross-validation of missions like CryoSat using the ICESat off-nadir capacity, a study was conducted to determine the geolocations of crossovers between two different repeat groundtrack Keplerian orbits. The general analytical solution was applied to ICESat vs. several other repeat groundtrack orbit mission, including the future ICESat-II mission. ICESat’s repeat groundtrack orbit was designed using a disturbing force model that includes only the Earth geopotential. Though the third body effect from the Sun and the Moon was neglected in the orbit design, it does in fact disrupt the repeatability condition of the groundtrack and consequently implies orbit correction maneuvers. The perturbations on ICESat orbit due to the third body effect are studied as a preliminary work towards including these forces in the design of the future ICESat-II repeat groundtrack orbit. / text
136

Solar Energy, Water, and Industrial Systems in Arid Lands: Technoecological Overview and Annotated Bibliography

Duffield, Christopher January 1978 (has links)
No description available.
137

Halophytes and their potential as landscape plants

Schaefer, Christina Maria, 1959- January 1988 (has links)
Based upon literature search, field investigation, examination of the halophyte collection at the Environmental Research Laboratory in Tucson, Arizona, and an expert survey, 97 salt-tolerant plants have been identified for the use as landscape plants. The plants were screened at salinity levels between 5 and 40 ppt which are critical for plant survival. The globally gathered data revealed information about landscape criteria, such as aesthetic value, climate amelioration, soil stabilization, color, form and drought tolerance, which were organized into architectural, engineering and design categories. These landscape halophytes range from herbaceous ground covers to woody trees. The data were filed in a computer data base, including detailed information about the description and performance of every plant, habitat requirements, maintenance, landscape values and economic uses. The data base, which is continually up-dated, is a search-type, which functions as an information storage system and is designed to provide plant selection by needed characteristics or intended use.
138

Effects of salinity on water extraction by roots under shallow groundwater table conditions

Ghamarnia, Houshang January 2001 (has links)
No description available.
139

CCD polarimetry as a probe of regions of recent star-formation

Draper, Peter Walter January 1988 (has links)
Chapter 1 of this thesis details the incorporation of a Charged Coupled Device (CCD) detector system with the Durham Imaging Polarimeter. The details include the physical characteristics of the device and the electronics and software associated with the device control and data storage. The introduction of the CCD detector system haa made necessary the inclusion of a super-achromatic half-wave plate in the polarimeter which has an inherent variability in its optic axis. Chapter 2of this work describes fully how suitable corrections for this effect can be made, and derives "first order" results. The CCD performance is examined in comparison with the detector used previously and hence the veracity of the new results is established. Chapter 3 is a relevant summary of the status of the astronomy of the immediate regions of recent star-formation. Chapter 4 describes multicolour polarimetry of NGC2261/R Mon covering the period 1979 to 1986. The data conclusively proves that the polarisation of R Mon must be due to effects close to R Mon (~ 14 astronomical units). This is evident because of the dynamic timescale of the variations of the polarisation of R Mon and the anomalous band of polarisations seen across the head of the nebula. The interpretation presented is an extension of the Elsasser and Staude (1978) method of polarising objects embedded within the confines of a nearly edge-on disk. Detailed polarisations within the main nebula body provide evidence for this extended interpretation and also for an extensive helical magnetic field which may extend into the disk. Also it is seen that R Mon must still be "shrouded" in material preventing light from directly reflecting in the main nebula body. It is not thought that the variations in the region close to R Mon are due to planetary bodies but to accretion from the disk. The results of this re-interpretation of the polarising mechanism are tentatively applied to other similar objects.
140

The Creative Advantage of Diverse City-regions: Local Context and Social Networks

Spencer, Gregory Martin 28 September 2009 (has links)
Local diversity is often credited with being a driver of creative economic activity. Comparative research on this topic is often however highly structural in nature and does little to address questions of agency. This work seeks to link the traditional regional science approach to questions of potential advantages of local diversity with a more bottom-up view of the creative process. From a theoretical perspective this involves incorporating the social psychology literature on the creative process as well as concepts from social network analysis with more aggregated spatial notions of creativity and diversity. More specifically, it addresses how different knowledge is connected through social interaction and how this fuels the creation of new ideas and ultimately creative economic activity. A number of empirical innovations are made in order to test these theoretical constructs beginning with an agent-model/simulation which illuminates how social networks form and evolve over space and time. These artificial networks suggest how agents embedded in diverse local contexts have a creative advantage by possessing greater access to a variety of knowledge. Subsequent statistical analysis of large secondary datasets seeks to provide external validity to the agent-model. The first demonstrates a strong relationship between local diversity and the concentration of creative economic activities across 140 Canadian city-regions. A key implication of this finding is that local diversity is more closely associated with certain types of economic activity, rather than overall economic performance. The second statistical analysis uses the Canadian General Social Survey to compare the social network characteristics of individuals. This analysis shows that people engaged in creative industries and occupations tend to have larger, more dynamic, and more diverse sets of social relations than any other category of worker. The dissertation concludes with a model that suggests policy interventions should focus on developing local environments that provide the necessary conditions in which creative activity can thrive, rather than attempting to intervene directly in the creative process itself.

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