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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.
341

Landforms along the Lower Columbia River and the Influence of Humans

Cannon, Charles Matthew 10 April 2015 (has links)
River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. Natural levees flank most channels in the upper reaches, locally including areas of ridge and swale topography and crevasse splays that intrude into backswamps. Other Holocene process regimes affecting floodplain morphology have included volcanogenic deltas, tributary fans, dunes, and landslides. Pre-Holocene landforms are locally prominent and include ancient fluvial deposits and bedrock. Historical changes to streamflow regimes, floodplain isolation by flood-control systems, and direct anthropogenic disturbance have resulted in channel narrowing and limited the amount of floodplain that can be shaped by flowing water. Floodplain isolation has caused relative subsidence of tidal floodplains along much of the lower estuary. Most extant landforms are on trajectories controlled by humans and new landforms are mostly created by humans.
342

The effect of human activity on the middle course of the Tualatin River, Oregon

Carter, Lolita M. 01 January 1975 (has links)
A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development. There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers. Effluents from sewage treatment plants flowing into the tributaries that drain the highly urbanized eastern areas of the river basin are the main cause of degraded water quality and algal biomass in the lower reaches of the river. The Tualatin River above the mouth of Rock Creek is relatively unpolluted, but downstream from Rock Creek the river is highly eutrophic and during the periods of low flow in the summer serves as a sewage oxidation channel. In this same portion of the river there is also evidence that nitrification occurs. Winter floods leach nitrate-nitrogen from the basin, but in the summer the possibility exists. that nitrate-nitrogen may be a limiting nutrient for algal productivity in the river above Hillsboro. The principal source of poly-phosphates is from sewage treatment plant effluents, but concentrations of poly-phosphates in the middle reaches of the river indicate that there is a natural source of poly- and/or ortho-phosphates in the watershed. Removal of phosphorous compounds from the effluents probably would not affect the large algal blooms occurring in the river below Hillsboro. Trace metal analyses indicated that iron, potassium, nickel, zinc, lead, copper, cobalt, and chromium concentrations were higher during flooding. Turbidity readings suggest that these trace elements are deposited on the floodplain. Melted snow water, which caused one of the winter floods, contained concentrations of zinc, ·copper, and lead greater than those found in the river during the flood. Greater concentrations of arsenic and zinc came from farmland than from urban areas. Diversities of the net plankton as measured by the Shannon-Weaver Index did not change from season to season, nor with downstream flow. Species in the net plankton were benthic forms at the upper stations and planktonic forms downstream from Hillsboro, especially in the summer when the reduced flow caused the river to pond. The enriched effluents from Rock Creek did not affect the diversity of the organisms downstream, but supported a larger biomass. By rating the diversities with other studies it was found that the middle course of the Tualatin River is eutrophic but not heavily polluted. A diurnal study was especially valuable from April to September, inclusive, when insolation and temperatures favored biological activities such as photosynthesis and decomposition. From November to January little diurnal change in the water quality was found. Farming had its greatest impact in the quantity of water and municipalities had a more serious impact on the water quality in the middle course of the Tualatin River. Even with the reduced flow from agricultural irrigation, the river can maintain relatively good water quality, except when effluents from sewage plants caused highly eutrophic conditions.
343

Fire and Aerosol Modeling for Air Quality and Climate Studies

Mezuman, Keren January 2019 (has links)
Open burning of biomass and anthropogenic waste is a major source of aerosols at the biosphere-atmosphere interface, yet its impact on Earth’s climate and air quality is not fully understood due to the intricate feedbacks between the natural environment and human activities. Earth system models (ESMs) are a vital tool in the study of these aerosol-biosphere-atmosphere interactions. ESMs allow the estimation of radiative forcing and climate impacts in terms of changes to temperature and precipitation as well as the attribution to natural or anthropogenic drivers. To provide coherent results, however, ESMs require rigorous development and evaluation against observations. In my work I use the NASA-GISS ESM: ModelE. One of its strengths lie in its detailed aerosol schemes that include microphysics and thermodynamic partitioning, both necessary for the simulation of secondary inorganic aerosols. To overcome one of ModelE’s weaknesses, namely its lack of interactive biomass burning (BB) emissions, I developed pyre: ModelE’s interactive fire emissions module. pyrE is driven by flammability and cloud-to-ground lightning, both of which are calculated in ModelE, and anthropogenic ignition and regional suppression parameterizations, based on population density data. Notably, the interactive fire emissions are generated from the flaming phase in pyrE (fire count), rather than the scar left behind (burned area), which is commonly used in other interactive fire modules. The performance of pyrE was evaluated against MODIS satellite retrievals and GFED4s inventory, as well as simulations with prescribed emissions. Although the simulated fire count is bias-high compared to MODIS, simulated fire emissions are bias-low compared to GFED4s. However, the bias in total emissions does not propagate to atmospheric composition, as pyrE simulates aerosol optical depth just as well as a simulation with GFED4s prescribed emissions. Upon the development and evaluation of the fire-aerosol capabilities of ModelE, I have utilized it, with the EVA health model, to study the health impacts of outdoor smoke in 1950, 2015, and 2050. I find that chronic exposure to aerosols (PM2.5) is the main driver of premature deaths from smoke exposure, yet by 2050, acute exposure to ozone, formed downwind of BB smoke plumes, is projected to cause more premature deaths than exposure to PM2.5. I estimate the annual premature deaths from BB and waste burning (WB) smoke in 1950 to be ~41,000 and ~19,000, respectively, and in 2015 to be ~310,000 and ~840,000, respectively. By 2050 I project 390,000 and 1.5 million premature deaths from BB and WB respectively. In light of the growing impact of WB smoke exposure I identify the need to scale up viable waste management practices in regions of rapid population growth.
344

The Interactions of Stance Width and Feedback Control Gain: A Modeling Study of Bipedal Postural Control

Scrivens, Jevin Eugene 09 July 2007 (has links)
By understanding and mimicking characteristics of postural control used by animals, scientist and engineers may develop standing autonomous robots that work safely within home environments, and treatment strategies that help people overcome postural impairments. To increase our understanding of postural control we developed physical and computational models of standing posture to explain the interrelation of stance width and feedback gain in controlling the stability and dynamics of the postural response. These models facilitated precise analysis of mechanical dynamics and their effects on compliant feedback control, and provided a physical implementation to verify predictions developed from simulation. We show that a scaling of active feedback gain is required to maintain postural stability. These results are consistent with previous studies that have shown that a correlation exists between increased stance width and decreased postural responses. However, these studies have not quantified the relation between stance and the active control of standing posture. This scaling of gains that we show is dependent on the changing kinematic relations of the mechanical structure as it undergoes stance width adjustments. Specifically, we show that increasing stance width increases the leverage of the mechanical system. Feedback gains must be reduced by the reciprocal of the increase in mechanical leverage in order to maintain a consistent postural response; otherwise, the system may become unstable with increasing oscillations. We also showed that increasing magnitudes of intrinsic stiffness increases postural stability by facilitating stable responses over larger ranges of active feedback gain and increasing the stability of responses by decreasing settling time, oscillations, and displacement magnitude. The conclusions of this study were that the variation of mechanical leverage is responsible for changing the dynamics of the response during stance width variation, and that scaling of feedback gains with the changing mechanical leverage of stance width variations is required to maintain consistent response dynamics across stance widths.
345

Reception and Transformation of Zhuangzi¡¦s Philosophy in Taiwan¡¦s Modern Poetry

Ting, Hsu-hui 27 July 2009 (has links)
This study, conducted through an ¡¥aesthetics of reception¡¦ approach, analyzes the reception and transformation of Zhuangzi¡¦s philosophy in Taiwan¡¦s modern poetry, during the 1949 to 2008 period, with the focus on its development and accumulated value under Zhuangzi¡¦s influence. The value lies in the efforts of Taiwan¡¦s poets who inherited classical cultures from which they created a new spirit. This new spirit constructed the new aesthetics that paved the way for Taiwan¡¦s modern poetry (present and future), and even for Chinese poetry overall, in modern times. Chapters 2 and 3 respectively discuss how Taiwan¡¦s modern poetry received and transformed the fish and butterfly images in The Book of Zhuangzi. In Chapter 2, the metaphorical images in Taiwan¡¦s modern poetry, like the legendary Big Fish, the stranded fish trapped in a dry rut, spit on one another to stay wet, and small fish are also discussed with the conclusion reached that the images are actually projections, the poets¡¦ self-images. The fish images embody some significant archetypes and represent the aesthetics of self-forgetfulness. Chapter 3 discusses the butterfly images with metaphors of formless life, joys of rebirth, understanding of true self and the pursuit of reincarnation. The butterfly images also reflect significant archetypes and represent the concepts of metamorphosis and the anthropomorphic aesthetics of endowing objects with the philosophies of human beings. The archetypes and aesthetics of fish and butterfly images are also the key to evaluating the aesthetics in The Book of Zhuangzi. This key value has been influential in the reception and transformation of Zhuangzi¡¦s philosophy in Taiwan¡¦s modern poetry. Chapter 4 further explains that self-forgetfulness and the aesthetics of endowing objects with the philosophies of human beings can define the location of ¡¥I¡¦ in Zhuangzi¡¦s ¡§observing things by other things¡¨, the conceptual basis of Zhuangzi¡¦s insistence upon viewing all the natural beings from the same reflective perspective. These ideas not only served as spiritual nourishment for Taiwan¡¦s poets in hard times but also helped them to realize the unifying aesthetics: that all beings exist as a whole; this explains why Taiwan¡¦s modern poetry has a ¡¥self-forgetful¡¦ aesthetics in viewing things. It signifies a new stage of poetry and poetics in Taiwan. This study also labors on the interpretation of individual modern poems. Many excellent poems involving Zhuangzi¡¦s philosophy are considered difficult to interpret, which is mainly due to people¡¦s unfamiliarity with the allusions, images and thoughts in The Book of Zhuangzi. This study provides the methodology for interpreting poems involving Zhuangzi and provides approaches of such reading. In regard to modern poetry, it provides a basic and practical contribution. The Book of Zhuangzi has proven influential both to poets and modern poetry in general, in Taiwan, not only for the past 60 years but as the inspiration of a new spirit by enhancing the spiritual life of the whole of humanity.
346

Tratta di esseri umani per lo scopo sessuale e corruzione in Brasile: un'analisi approfondita sul collegamento tra due fenomeni criminali / Trafficking in Human Beings for the Purpose of Sexual Exploitation, and Official Corruption in Brazil

CIRINEO SACCO, ANDREA 10 March 2008 (has links)
Questa tesi versa sull'interrelazione tra due fenomeni criminali: tratta di esseri umani, particolarmente donne e bambini allo scopo di sfruttamento sessuale, e corruzione in Brasile. Lo studio è basato su quattro fonti diverse di dati empirici: tre fonti secondarie e un questionario (survey). Il capitolo I esplora l'importanza del tema, i problemi affrontati nello studio e gli obbiettivi della tesi. Il capitolo II presenta la letteratura scientifica sulla quale la tesi è basata, l'ipotesi principale, la metodologia applicata e i dati utilizzati. Il capitolo III analizza i risultati empirici provenienti dalle quattro fonti di dati, i quali dimostrano 1) la dipendenza della tratta di esseri umani sulla corruzione; 2) i punti più vulnerabili per la corruzione durante la catena della tratta e la catena della giustizia penale; 3) le differenze regionali e la tendenza della tratta di esseri umani e della corruzione in Brasile. L'analisi multivariata é utilizzata per dimostrare la forza della correlazione tra i due fenomeni. La dipendenza della tratta di esseri umani sulla corruzione è analizzata attraverso l'utilizzo del metodo qualitativo. Il capitolo V discute i risultati e presenta le conclusioni. / This thesis deals with the interrelationship between two criminal phenomena: trafficking in human beings, particularly women and minors for the purpose of sexual exploitation, and official corruption in Brazil. The study is based on empirical data from four different sources: three sets of secondary data and a survey. Chapter I highlights the importance of the study, the problems addressed by the thesis, as well as its objectives. Chapter II explores up-to-date scientific literature, the working hypothesis, applied methodology, and research design. Chapter III presents the empirical findings of each set of data which shows: 1) the dependence of Trafficking in Human Beings on Corruption; 2) the most vulnerable points for corruption during the trafficking and criminal justice chains; 3) and regional differences and trends on THB and Corruption in Brazil. Multivariate analysis is used: 1) to highlight the strength and of the interrelationship between Trafficking in Human Beings and Corruption; 2) and to establish predictability. The dependence of Trafficking on Official Corruption is analysed by means of qualitative method. Chapter V discusses the results and presents conclusions.
347

Simulation de mouvements humains complexes et prédiction de l'inconfort associé application à l'évaluation ergonomique du bouclage de la ceinture de sécurité /

Monnier, Gilles Verriest, Jean-Pierre. January 2005 (has links)
Thèse doctorat : Génie Mécanique. Biomécanique : Villeurbanne, INSA : 2004. / Thèse rédigée en anglais sauf le chapitre VIII. Titre provenant de l'écran-titre. Bibliogr. p. 247-254.
348

Discussion and determination of the most adequate method to be employed in the study of the interrelation and interaction of the economic, ethical, and religious factors in the life of organised communities, as illustrated in the case of the Vaishnava communities of Gujarat, or, The correlation of economic and social life with religious beliefs and general culture, so far as illustrated by the Vaishnavas of Gujarat

Thoothi, N. A. January 1924 (has links)
No description available.
349

A look at aging : balance ability and fall prevention interventions

Dunn, Brandie M, University of Lethbridge. Faculty of Arts and Science January 2009 (has links)
The main objective of this work is to address the growing concern of balance loss and falls in the aging population. The initial aspect looks at balance control in a dynamic environment. Observation of age and gender influence on motor control will be made related to a new dynamic balance testing platform (DBTP). The topic of focus in the second portion relates to reaction time in an unstable environment. Research has found that balance improves when physical activity is a part of daily life for seniors. Physical activity influence on reaction time will be investigated with a new approach to exercise classes for seniors. Finally, an understanding of motor control and balance may be acquired and physical activity incorporated into the life of an elderly individual, however this will never fully prevent falls from taking place. A novel approach to injury prevention due to falls is explored in the final portion of this thesis. Study One - Using a newly constructed dynamic balance testing platform (DBTP), balance ability of three age groups was observed in two visual conditions and in relation to gender. Center of Gravity excursion (COGex) was observed to determine the differences between age groups and gender. Platform response patterns were also observed to asses the functionality of the DBTP as a new tool for balance testing. Three things were found: 1) Age differencesrelated to platform movement suggested that balance decreased with age in both visual conditions. 2) Gender differences between COGex found that males covered the most distance in both visual conditions when compared to females. 3) Gender differences between platform characteristics showed that females balanced longer and had lower platform movement rate than males, in both visual conditions. In order to consider the DBTP as a new tool for determination of balance ability, more refined tests are necessary. Study Two - Using pre- and post-training tests, the effects of a Fitball® exercise program on performance in eight subjects was documented. The exercise program focused on improving dynamic balance and postural stability of seniors. To evaluate progress-related changes, pre and post-tests in a dynamic environment were applied. Center of gravity (COG) excursion, catch success rate, and balance success rate were quantified, and synchronized data collection of 3D motion capture (VICON v8i) and ground reaction force (2 KISTLER platforms) was analyzed. During pre- and post-tests, participants stood in a walk-like stance and were asked to catch a weighted ball, which dropped unexpectedly. Results showed no significant changes in balance success rate. Significant improvements were found, however, in both COG control and catch success rate following training (p 0.05). Study Three - Falls in the elderly are inevitable so it is necessary to take precautions. This study looks at falls in relation to velocity characteristics of various locations on the trunk, and contrasts them to activities of daily living (ADL) in 13 individuals. A threshold level was established to be 2.0m/s, a value that exceeded all maximum resultant velocities for ADL, but was superseded by all fall activity resultant velocities. This suggests that a life vest, which responds similar to a vehicle airbag, may be created and worn that will deploy past a threshold of 2.0m/s with the incidence of a fall. / xiii, 91 leaves : ill. ; 29 cm. --
350

Music normalizes visual and proprioceptive control of movement in Parkinson's disease

Sacrey, Lori-Ann Rosalind, University of Lethbridge. Faculty of Arts and Science January 2008 (has links)
The sensory control of movements has been shown to be impaired with Parkinson’s disease. I investigated the task, reach-to-eat, in which advancing of the limb towards a target is guided by vision and withdrawal of the grasped target to the mouth is guided by somatosensation (i.e., haptics and proprioception). Parkinson’s diseased subjects display an alteration in the balance of visual and proprioceptive guidance, such that they display increased visual fixation on the target prior to movement onset that persists following the grasp. Music therapy can normalize the balance between visual and proprioceptive guidance on the reach-to-eat task, as visual fixation with the target prior to movement onset is consistent with controls, and disengagement following grasp no longer differs from mild Parkinson’s disease subjects. These results are the first to demonstrate that music can have an ameliorating effect on the sensory impairments seen in the control of forelimb movements in Parkinson’s disease. / xiv, 147 leaves : ill. ; 29 cm. --

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