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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.
611

Place, politics, and property : negotiating allotment and citizenship for the Citizen Potawatomi, 1861-1891

Mosteller, Kelli Jean 14 July 2014 (has links)
This study explores the varied Citizen Potawatomi responses to federal assimilation and land policies from 1861 to 1891. The professed intention for these laws and treaties was to acculturate Native Americans into American society, but there was a clear ulterior motive to drastically reduce the land base of tribes in the West. The outcomes of policies that arranged for allotment and citizenship were mixed. The federal government successfully dispossessed the Citizen Potawatomi of large quantities of land and virtually every tribal member became a U.S. citizen, but few individuals became successful farmers or businessmen. The government's efforts also unintentionally resulted in fostering a stronger tribal identity and better tribal organization to argue for the collective and individual rights of Citizen Potawatomi tribal members. As the United States became embroiled in a devastating civil war and thousands of Americans flooded west in search of opportunity, the Citizen Potawatomi entered into a treaty agreement to allot their lands and become U.S. citizens. The Citizen Potawatomi treaty of 1861 forced tribal members to abandon the practice of holding land in common by stipulating that they must accept allotments and become U.S. citizens. Unintended consequences of the flaws in the government's plan were the near-complete loss of lands allotted to the Citizen Potawatomi, and a muddying of their legal status. Within a decade a large percentage of tribal members were landless and sought a new home in Indian Territory. By 1872 the Citizen Potawatomi better understood how to use non-Indian methods to fight for favorable allotments and full enfranchisement in the extralegal condition that characterized both their new home and themselves. Two decades later, when the federal government opened thousands of acres of Citizen Potawatomi lands to non-Indian settlement, tribal members had learned a painful, but strengthening lesson. To salvage a distinct tribal identity and political independence, the Citizen Potawatomi took command of their relationship with the federal government by demonstrating knowledge of the legislation that defined their legal rights and manipulating the inconsistent application of those policies. / text
612

Identity negotiation: The perspective of Asian Indian women

Mehta, Pangri 01 June 2009 (has links)
Traditional Indian cultural narratives are pervasive and serve to typify personal identity and experience. These cultural narratives portray Indian women as a wife and mother, nurturing, obedient, forbearing, soft-spoken, and the primary transmitters of the ethnic culture. American culture, on the other hand, encourages independence, individualism and a more elastic view towards gender. As assimilation theory suggests, Asian Indians in the United States are likely to assimilate at least some degree into American society. Accordingly, these narratives make up the cultural identity of Indian women in the United States. The contrasting cultural narratives shape the identities of Indian women residing in the United States and have the capacity to influence Asian Indian women's attitudes toward traditional Indian views about marriage, culture and gender expectations. Using data from interviews with eleven college-aged Indian women, I examine how college-aged Asian Indian women in a large southern university negotiate their Indian identity in American society. The personal identities they construct are much more diverse and complex than the typifications in the cultural narrative of 'Indian women.' Specifically, I explore how these women understand expectations of dating and marriage, education and independence, and clothing and demeanor, as well as how each of these are negotiated and shaped to fit the personal identities these women are constructing for themselves.
613

Understanding the Coupled Surface-Groundwater System from Event to Decadal Scale using an Un-calibrated Hydrologic Model and Data Assimilation

Tao, Jing January 2015 (has links)
<p>In this dissertation, a Hydrologic Data Assimilation System (HDAS) relying on the Duke Coupled surface-groundwater Hydrology Model (DCHM) and various data assimilation techniques including EnKF (Ensemble Kalman Filter), the fixed-lag EnKS (Ensemble Kalman Smoother) and the Asynchronous EnKF (AEnKF) was developed to 1) investigate the hydrological predictability of precipitation-induced natural hazards (i.e. floods and landslides) in the Southern Appalachians in North Carolina, USA, and 2) to characterize the seasonal (wet/dry) and inter-annual variability of surface-groundwater interactions with implications for water resource management in the Upper Zambezi River Basin (UZRB) in southern Africa. The overarching research objective is to improve hydrologic predictability of precipitation-induced natural hazards and water resources in regions of complex terrain. The underlying research hypothesis is that hydrologic response in mountainous regions is governed by surface-subsurface interaction mechanisms, specifically interflow in soil-mantled slopes, surface-groundwater interactions in recharge areas, and wetland dynamics in alluvial floodplains at low elevations. The research approach is to investigate the modes of uncertainty propagation from atmospheric forcing and hydrologic states on processes at multiple scales using a parsimonious uncalibrated hydrologic model (i.e. the DCHM), and Monte Carlo and Data-Assimilation methods. In order to investigate the coupled surface-groundwater system and assess the predictability of precipitation-induced natural hazards (i.e. floods and landslides) in headwater basins, including the propagation of uncertainty in QPE/QPF (Quantitative Precipitation Estimates/Forecasts) to QFE/QFF (Quantitative Flood Estimates/Forecasts), the DCHM model was implemented first at high spatial resolution (250m) in the Southern Appalachian Mountains (SAM) in North Carolina, USA. The DCHM modeling system was implemented subsequently at coarse resolution (5 km) in the Upper Zambezi River Basin (UZRB) in southern Africa for decadal-scale simulations (i.e. water years from 2002 to 2012). </p><p>The research in the SAM showed that joint QPE-QFF distributions for flood response at the headwater catchment scale are highly non-linear with respect to the space-time structure of rainfall, exhibiting strong dependence on basin physiography, initial soil moisture conditions (transient basin storage capacity), the space-time organization of runoff generation and conveyance mechanisms, and in particular interflow dynamics. The errors associated with QPEs and QPFs were characterized using rainfall observations from a dense raingauge network in the Pigeon River Basin, resulting in a simple linear regression model for adjusting/improving QPEs. Deterministic QFEs simulated by the DCHM agree well with observations, with Nash–Sutcliffe (NS) coefficients of 0.8~0.9. Limitations with state-of-the-science operational QPF and the impact of even limited improvements in rainfall forcing was demonstrated through an experiment consisting of nudging satellite-like observations (i.e. Adjusted QPEs) into operational QPE/QPF that showed significant improvement in QFF performance, especially when the timing of satellite overpass is such that it captures transient episodes of heavy rainfall during the event. The research further showed that the dynamics of subsurface hydrologic processes play an important role as a trigger mechanism of shallow landslides through soil moisture redistribution by interflow. Specifically, transient mass fluxes associated with the temporal-spatial dynamics of interflow govern the timing of shallow landslide initiation, and subsequent debris flow mobilization, independently of storm characteristics such as precipitation intensity and duration. Interflow response was shown to be dominant at high elevations in the presence of deep soils as well as in basins with large alluvial fans or unconsolidated debris flow deposits. In recharge areas and where subsurface flow is an important contribution to streamflow, subsurface-groundwater interactions determine initial hydrologic conditions (e.g. soil moisture states and water table position), which in turn govern the timing and magnitude of flood response at the event scale. More generally, surface-groundwater interactions are essential to capture low flows in the summer season, and generally during persistent dry weather and drought conditions. Future advances in QFF and landslide monitoring remain principally constrained by progress in QPE and QPF at the spatial resolution necessary to resolve rainfall-interflow dynamics in mountainous regions.</p><p>The predictability of QFE/QFF was further scrutinized in a complete operational environment during the Intense Observing Period (IOP) of the Integrated Precipitation and Hydrology Experiment (IPHEx-IOP), in order to investigate the predictability of floods (and flashfloods) in headwater catchments in the Southern Appalachians with various drainage sizes. With the DCHM, a variety of operational QPEs were used to produce hydrological hindcasts for the previous day, from which the final states were used as initial conditions in the hydrological forecast for the current day. Although the IPHEx operational testbed results were promising in terms of not having missed any of the flash flood events during the IOP with large lead times of up to 6 hours, significant errors of overprediction or underprediction were identified that could be traced back to the QPFs and subgrid-scale variability of radar QPEs. Furthermore, the added value of improving QFE/QFF through assimilating discharge observations into the DCHM was investigated for advancing flood forecasting skills in the operational mode. Both the flood hindcast/forecast results were significantly improved by assimilating the discharge observations into the DCHM using the EnKF (Ensemble Kalman Filter), the fixed-lag EnKS (Ensemble Kalman Smoother) and Asynchronous EnKF (AEnKF). The results not only demonstrate the utility of discharge assimilation in operational forecasts, but also reveal the importance of initial water storage in the basin for issuing flood forecasts. Specifically, hindcast NSEs as high as 0.98, 0.71 and 0.99 at 15-min time-scales were attained for three headwater catchments in the inner mountain region, demonstrating that assimilation of discharge observations at the basin’s outlet can reduce the errors and uncertainties in soil moisture. Success in operational flood forecasting at lead times of 6, 9, 12 and 15hrs was also achieved through discharge assimilation, with NSEs of 0.87, 0.78, 0.72 and 0.51, respectively. The discharge assimilation experiments indicate that the optimal assimilating time window not only depends on basin properties but also on the storm-specific space-time-structure of rainfall within the basin, and therefore adaptive, context-aware configurations of the data assimilation system should prove useful to address the challenges of flood prediction in headwater basins.</p><p>A physical parameterization of wetland hydrology was incorporated in the DCHM for water resource assessment studies in the UZRB. The spatial distribution of wetlands was introduced in the model using probability occurrence maps generated by logistic regression models using MODIS reflectance-based indices as predictor variables. Continuous model simulations for the 2002-2012 period show that the DCHM with wetland parameterization was able to reproduce wetland hydrology processes adequately, including surface-groundwater interactions. The modelled regional terrestrial water storage anomaly (TWSA) captured very well the inter- and intra-annual variability of the system water storage changes in good agreement with the NASA’s GRACE (Gravity Recovery and Climate Experiment) TWSA observations. Specifically, the positive trend of TWSA documented by GRACE was simulated independently by the DCHM. Furthermore, it was determined that the TSWA positive trend results from cumulative water storage in the sandy soils of the Cuando-Luana sub-basin when shifts in storm tracks move rainfall to the western sector of the Angolan High Plateau. </p><p>Overall, the dissertation study demonstrates the capability of the DCHM in predicting specific characteristics of hydrological response to extreme events and also the inter- and intra-annual variability of surface-groundwater interactions at a decadal scale. The DCHM, coupled with slope stability module and wetland module featuring surface-groundwater interaction mechanism, not only is of great potential in the context of developing a regional warning system for natural hazards (i.e. flashfloods and landslides), but also is promising in investigating regional water budgets at decadal scale. In addition, the DCHM-HDAS demonstrated the ability to reduce forecasting uncertainty and errors associated with forcing data and the model proper, thus significantly improving the predictability of natural hazards. The HDAS could also be used to investigate the regional water resource assessment especially in poorly-gauged regions (e.g. southern Africa), taking advantage of satellite observations.</p> / Dissertation
614

Geostationary satellite observations of ozone air quality

Zoogman, Peter William 14 October 2013 (has links)
Ozone in surface air is the primary cause of polluted air in the United States. The current ozone observing network is insufficient either to assess air quality or to fully inform our understanding of the factors controlling tropospheric ozone. This thesis investigates the benefit of an instrument in geostationary orbit for observing near surface ozone using Observing System Simulation Experiments (OSSEs). / Earth and Planetary Sciences
615

Consonant assimilation in early phonological development : a phonetic perspective

Kim, Namhee, 1975- 03 December 2010 (has links)
Consonant assimilation between noncontiguous consonants within words is one of the characteristic error patterns for children reported in observations of the earliest periods of speech acquisition. Previous analyses of consonant assimilation in young children have been based on formal phonological theories. However, phonological perspectives do not provide comprehensive explanations for potential mechanisms underlying children’s output forms when they are different from adult forms. The present study tests the hypothesis that functionalist phonetic approaches have the potential to provide a more comprehensive explanation for assimilation patterns in children’s speech output. Consonant assimilation patterns were observed from the onset of word use (approximately 12 months) to 36 months of age in ten English-speaking children. Assimilated forms in consonant-vowel-consonant (CVC) and consonant-vowel-consonant-vowel (CVCV) words produced by these children were analyzed. Predictions based on the Frame/Content perspective were evaluated relative to place and manner characteristics, vowel context, word level, and development over time. Results confirmed the prediction that motorically less available forms assimilate to more available forms in children acquiring ambient language speech patterns. Labial and coronal place of articulation more frequently motivated assimilation than dorsal. Stop and nasal manner of articulation more frequently motivated assimilation than fricative. The vowel context effects in assimilated forms were stronger for lingual consonants than labials and greater for CVCV more than CVC word forms. A word shape effect was observed related to place characteristics, direction of assimilation, and vowel context. A word position effect was observed for manner assimilations. Analysis of developmental trends revealed that children maintained a preference for motorically available forms in assimilations. The vowel context effects decreased over time. These findings suggest that patterns of consonant assimilation in these children are strongly motivated by behaviors already available within their production system capacities from the pre-linguistic babbling period, rather than being driven by patterns found in the targets they are attempting. Results also suggest that perceptual influences from language input may influence assimilation patterns to a lesser extent. Functionalist phonetic approaches that emphasize the understating of the production system and perceptual influences played a seminal role in understanding of children’s speech development relative to assimilation patterns. / text
616

Influence of atmospheric carbon dioxide levels on absorption of nutrients by plants

Ghoddoussi, Djafar, 1933- January 1970 (has links)
No description available.
617

Diagnostics and Generalizations for Parametric State Estimation

Nearing, Grey Stephen January 2013 (has links)
This dissertation is comprised of a collection of five distinct research projects which apply, evaluate and extend common methods for land surface data assimilation. The introduction of novel diagnostics and extensions of existing algorithms is motivated by an example, related to estimating agricultural productivity, of failed application of current methods. We subsequently develop methods, based on Shannon's theory of communication, to quantify the contributions from all possible factors to the residual uncertainty in state estimates after data assimilation, and to measure the amount of information contained in observations which is lost due to erroneous assumptions in the assimilation algorithm. Additionally, we discuss an appropriate interpretation of Shannon information which allows us to measure the amount of information contained in a model, and use this interpretation to measure the amount of information introduced during data assimilation-based system identification. Finally, we propose a generalization of the ensemble Kalman filter designed to alleviate one of the primary assumptions - that the observation function is linear.
618

Plant uptake of iron, copper, and zinc from soils as influenced by source materials

Greene, Robert Edward, 1930- January 1960 (has links)
No description available.
619

Phonetics and Phonology of Regressive Voicing Assimilation in Russian Native and Non-native Speech

Samokhina, Natalya January 2010 (has links)
In recent years, a great deal of research on second language (L2) acquisition has been concerned with non-target production of L2 learners, addressing issues such as native language (L1) transfer into L2 and the nature and source of developmental errors. Previous studies have mostly focused on the analysis of discrete L2 segments (Flege 1987, 1999; Major & Kim 1996), rather than on L2 phonological patterns. This study, however, examines the production of sequences of sounds in Russian L1 and L2 from both the phonetic and phonological perspectives.This dissertation investigates native and non-native production of real and nonsense words containing obstruent clusters in which a phonological phenomenon known as regressive voicing assimilation is required. In Russian, forms like lodka `boat' are rendered orthographically with a voiced obstruent which is pronounced as a voiceless one when followed by a voiceless obstruent. The results of the experiments reveal several production patterns in L1 and L2 speech as well as gradiency in devoicing which are further analyzed within the stochastic Optimality Theory framework. Categorical production is accounted for by the re-ranking of L1 and L2 constraints; whereas, gradiency in production is viewed as a result of the re-ranking of constraints within phonetically detailed constraint families.
620

Medias skildring av det svenska samhället : En diskursanalys om integration och utanförskap

Engkvist, Johan January 2008 (has links)
Denna uppsats syftar till att tydliggöra de mediala diskurser som finns om integration och utanförskap i tidningsartiklar. Tidningsartiklarna sträcker sig över två tidsperioder, 1996-1997 och 2006-2007. En frågeställning som uppsatsen försöker besvara är om analysens tidningsartiklar går att koppla till Ruth Levitas diskursmodeller om socialt utanförskap. Den centrala teoretiska utgångspunkten är ett postkolonialt perspektiv. Uttrycket ”vi och dem” utgör en röd tråd genom hela uppsatsen. Metoden för analysen är det diskursanalytiska verktyget diskursteori. Uppsatsens analys visar på tre centrala teman där samtliga utgår från utanförskap. Dessa teman är kultur och utanförskap, fördelning och utanförskap samt arbete och utanförskap.

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