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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.
1

Comparative Practices & Perspectives: Gender, Development and Empowerment in Uttarakhand, India and Northern Virginia

Duke, Sara 01 January 2008 (has links)
The following thesis is a qualitative comparative case study which investigated the values, practices, perspectives, and strategies of Indian and American community organizers (practitioners and volunteers of non-profits and non-governmental organizations) who use microfinance, including savings schemes, as an instrument within the social intermediation process of developing disadvantaged women's capacities for self-sufficiency/empowerment. The focused inquiry was conducted through similarly structured in-depth interviews of directors, staff members and volunteers/community-based organizers of a women's business center in Northern Virginia, a large U.S. metropolitan area, and a women's federation in the rural Himalayas of Uttarakhand, India. Interview questions focused on savings, social intermediation, and financial sustainability/subsidization, which are three significant facets of microfinance. Katz's framework for constructing analytical topographies, contour lines, and countertopographies was used to structure of the various levels of analysis. Contour lines were drawn from the similarities between the two organizations. Differences were explained by situating each organization in Mayoux's theoretical paradigms of "Women's Empowerment through Microfinance." Analyses concluded with the construction of countertopographies on practices and strategies aimed towards collectively empowering women in disparate places around the world.
2

Paléoréseaux hydrographiques et paléoreliefs en période de tectonique active : l’Eocène-Miocène basal (45-20 Ma) du bassin du SE de la France, témoin de la formation des Alpes occidentales / Palaeodrainage networks and palaeotopographies during an active tectonic period : the Eocene-early Miocene (45-20 Ma) of the French South Alpine Foreland Basin, witness of the Western Alps formation

Grosjean, Anne-Sabine 16 May 2013 (has links)
Les réseaux hydrographiques sont les principaux vecteurs de l'érosion des reliefs et de transport des sédiments jusqu'aux bassins. Leur développement, contraint par la tectonique et le climat, est au coeur des recherches sur l'évolution des chaînes de montagnes. Or, la dynamique et la stabilité des réseaux de drainage dans les bassins d'avant-pays, soumis à la subsidence flexurale et à la tectonique locale, restent mal connus. Cette étude s'intéresse à la formation et la dynamique érosive du réseau de drainage du bassin d'avant-pays du SE de la France en lien avec l'exhumation des Alpes occidentales à l'Eocène-Miocène basal (45-20 Ma). Les résultats sédimentologiques et structuraux montrent que ce réseau a été formé précocement au cours de la subsidence du bassin à la faveur de la tectonique compressive régionale. Les sédiments Eocènes déposés dans les paléo-vallées reflètent d'abord un réseau local. A l'Oligocène, l'exhumation des Alpes induit l'extension du réseau jusqu'aux massifs internes alors en érosion. Les galets exotiques déposés dans le bassin contiennent des fractures dévoilant une circulation complexe d'eau (probablement météorique) dans les Alpes. L'étude géochimique des inclusions fluides indique que cette eau a été piégée dans ces veines sous environ 2 km de roches, suggérant l'altitude des reliefs alpins à l'Oligocène. Aujourd'hui, le réseau hydrographique réemprunte en partie les vallées Miocènes, indiquant une relative stabilité de sa géométrie depuis 25 Ma, malgré une activité tectonique constante. Ces résultats peuvent servir de contrainte aux modèles d'évolution des réseaux hydrographiques dans les bassins à différentes échelles spatio-temporelles / Drainage networks represent the main vectors of erosion of topographies and transport of sediments toward the basins. Their development is constrained by both tectonics and climate, and thus represents the focus of research of mountain belt evolution. However, in foreland basins, the drainage network dynamics and stability are still not well understood due to the overlapping effect of local tectonic activity on the flexural subsidence. This study focus on the formation and on the erosive dynamics of the drainage network in the French South Alpine Foreland Basin that is related to the Western Alps exhumation during the Eocene-early Miocene (45-20 Ma). Combined sedimentological and structural results show that the drainage network has been tectonically-formed during the early stage of subsidence of the basin due to the regional compressional stress. Primarily, the Eocene sediments deposited in the palaeovalleys highlight a local network. During the Oligocene, the Alps exhumation induces the development of the network to the internal massifs that are then eroded. Some exotic pebbles deposited in the basin contain veins that evidence for a complex water circulation (probably meteoric water) within the Alps. The geochemical study of fluid inclusions indicates that the water has been trapped under about 2 km of rocks suggesting the altitude of the alpine reliefs at the Oligocene. Despite a constant tectonic activity, the modern drainage network partially uses the Miocene palaeovalleys that suggest a geometrical stability since about 25 Ma. These results can serve to constrain the various models of drainage network evolution in basins at different space and time scales
3

Does Response Topography Affect Response Rates and Behavioral Persistence in Fixed-ratio Schedules?

Pedraza, Paloma 08 November 2011 (has links)
The purpose of this study was to compare response rates and resistance to extinction in single-task and multiple-task phases. Research was conducted with thirty undergraduate college students in a controlled experimental setting. Each Participant was exposed to 4 treatment phases: single-task, fixed-ratio of one (ST-FR1), multiple-task fixed-ratio of one (MT-FR1), single-task fixed-ratio of 5 (ST-FR5) and multiple-task fixed-ratio of 5 (MT-FR5) all beginning with a baseline phase and reverting back to baseline after the first two conditions were presented. Half of the Participants received the single-task phase first, and the other half received the multiple-task phase first, in order to observe the behavior in transition. A trials-to-criterion measure was used to determine how long it took each Participant’s behavior to adapt to the new contingency in the next phase, which was presented without any signal. The data reveal that regardless of the order of phase presentation it took Participants more than twice as long to reach the criterion in the single-task phases, than in the multiple-task phases.
4

Sliding bearings in heavy duty engines : A bearing wear comparative study / Glidlager i tunga motorer : En jämförande studie om lagernötning

Anslin, Mathias, Bölke, Alexander January 2017 (has links)
Start-stop systems are widely used in the car industry today but have not yet been fully implemented in the heavy-duty vehicle industry. The greater loads arising in the engines leads to excessive wear of the hydrodynamic bearings during starts and stops which has a distinct impact on the machine´s lifetime performance and reliability. This master thesis involves a comparative study of how different surface topographies of a shaft affects hydrodynamic bearing wear during start and stop conditions. The objective was to see if one can extend the bearing lifetime by doing minor changes to the shaft surface. This has been done by redesigning an existing start-stop test rig, increasing its operating system oil temperature to 90°C to provide a more accurate description of the bearing environment, to be able to conduct a series of start-stop cycling experiments. Upon examination of the experiment results, it becomes clear that a more polished surface of the shaft does reduce bearing wear significantly during starts and stops. It was also noticed that a more polished shaft surface does reach full-film lubrication at a lower rotational speed of the shaft, separating the shaft and the bearing surfaces. / Start-stoppsystem används idag i stor utsträckning inom bilindustrin men har ännu inte blivit implementerat fullt ut i den tunga fordonsindustrin. De större belastningarna som uppstår i motorn leder till överdrivet slitage på de hydrodynamiska glidlagren under start och stopp och har en tydlig inverkan på maskinens livslängd och pålitlighet. Detta examensarbete har innefattat en jämförande studie om hur olika axelytor påverkar nötningen av hydrodynamiska glidlager vid start och stoppförhållanden. Målet var att se ifall man kan lyckas förlänga lagrets livslängd genom att genomföra mindre förändringar av axelytan. Detta har utförts genom att omkonstruera en befintlig start-stopprigg, ökat oljesystemets driftstemperatur till 90°C för att ge en mer exakt beskrivning av den riktiga lagermiljön, för att sedan ha utfört en serie start och stopp experiment. Resultaten från experimenten visade tydligt att en mer polerad axelyta minskar lagerslitningen avsevärt under start och stopp. Det noterades också att en mer polerad axelyta ger fullfilmssörjning vid en lägre axelrotationshastighet, varvid axeln och lagerytorna separeras.
5

Jewish Space

Narron, Callie 21 September 2012 (has links)
No description available.
6

Problématiques d’analyse numérique et de modélisation pour écoulements de fluides environnementaux / Mathematical modeling and numerical analysis of environmental flows

Cathala, Mathieu 18 October 2013 (has links)
Ce travail s'inscrit dans l'étude mathématique d'écoulements de fluides environnementaux. Nous en abordons deux aspects, à travers deux contextes distincts d'application.En lien avec la simulation des écoulements en milieux poreux, on s'intéresse dans une première partie à la discrétisation d'opérateurs de diffusion anisotropes hétérogènes par des méthodes de volumes finis sur des maillages généraux. Dans le but d'obtenir des solutions approchées qui respectent les bornes physiques des modèles, notre attention se porte sur la conservation du principe du maximum pour les opérateurs elliptiques. Nous présentons des mécanismes généraux permettant de corriger tout schéma volumes finis afin de garantir un principe du maximum discret tout en préservant certaines de ses propriétés principales. On étudie en particulier les propriétés de coercivité et de convergence des schémas corrigés.La deuxième partie est consacrée à la construction de modèles approchés pour la propagation des vagues en eaux peu profondes et sur des topographies irrégulières. A cet effet, nous proposons tout d'abord une adaptation de la démarche d'étude classique à des écoulements bidimensionnels sur des topographies polygonales. Dans un cadre plus général, nous développons ensuite une démarche formelle qui débouche sur des alternatives non locales à quelques modèles classiques (équations de Saint-Venant, équations de Serre, système de Boussinesq). Ces nouveaux modèles contiennent des termes régularisants pour les contributions du fond. / This work investigates two research questions associated with environmental flows and their mathematical modeling.The first part is devoted to the development of finite volume methods for anisotropic and heterogeneous diffusion operators arising in models of porous media flows. To ensure that the approximate solutions lie within physical bounds, we aim at maintaining a discrete analogous of the maximum principle for elliptic operators. Starting from any given cell-centered finite volume scheme, we present a general approach to devise non-linear corrections providing a discrete maximum principle while retaining some main properties of the scheme. In particular, we study the coercivity and convergence properties of the modified schemes.The second part of this work focuses on the derivation of approximate models for shallow water wave propagation over rough topographies. In the particular case of one-dimensional polygonal bottom profiles, we first propose an adaptation of the usual derivation method using complex analysis tools. We then develop a formal approach to account for more general topographies. We propose nonlocal alternatives to some classical models (namely Saint-Venant equations, Serre equations and Boussinesq system). All these alternative models only involve smoothing contributions of the bottom.
7

Colombi, Matteo (Hrsg.), Stadt, Mord, Ordnung. Urbane Topographien des Verbrechens in der Kriminalliteratur aus Ost- und Mitteleuropa: Buchbesprechung

Altmann, Kristin Elisabeth 16 July 2020 (has links)
Matteo Colombi und seine Co-Autoren verfolgen mit Stadt, Mord, Ordnung ein anspruchsvolles Ziel, nämlich den osteuropäischen Krimi und seine teilweise exotisch wirkenden Schauplätze von allen Seiten zu beleuchten: „Kann man behaupten, dass jede ost- und mitteleuropäische Stadt ihre spezifische Topographie des Verbrechens produziert, die sich aus der Geschichte und Geographie des Ortes speist?“, so eine der zu untersuchenden Fragen. Der Sammelband dokumentiert die Ergebnisse der internationalen Konferenz „Stadt – Mord – Ordnung. Urbane Settings in der Kriminalliteratur aus Ost-Mittel-Europa“, die vom 25. bis zum 26. 03. 2010 am Geisteswissenschaftlichen Zentrum Geschichte und Kultur Ostmitteleuropas (GWZO) in Leipzig stattfand. Insgesamt sind es dreizehn Aufsätze von Slavisten, Kultur- und Literaturwissenschaftlern, Narratologen und Komparatisten, in denen das Thema umfassend behandelt wird, denn die Konferenz stand in Zusammenhang mit dem von Alfrun Kliems geleiteten DFG-Projekt „Imagination des Urbanen in Ostmitteleuropa. Stadtplanung – Visuelle Kultur – Dichtung im 20. Jahrhundert“ (2006–2010), in dessen Rahmen Stadtlandschaften nach der Wende untersucht wurden. Dies schließt eine Betrachtung der politischen, gesellschaftlichen und kulturellen Veränderungen dieser Zeit mit ein, die auch im Kriminalroman repräsentiert und verarbeitet werden.
8

EFFECTS OF INLET CONDITIONS, TURBINE DESIGN, AND NON-FLAT TOPOGRAPHY ON THE WAKE OF SCALED-DOWN WIND TURBINES

Diego Andres Siguenza Alvarado (16507221) 07 July 2023 (has links)
<p>This work is a five-article-based collection of published and to-be-published research articles that explore a novel combination of inlet conditions, wind turbine design, and non-flat topography by performing scaled-down experiments in a wind tunnel.</p>
9

Problématiques d'analyse numérique et de modélisation pour écoulements de fluides environnementaux

Cathala, Mathieu 18 October 2013 (has links) (PDF)
Ce travail s'inscrit dans l'étude mathématique d'écoulements de fluides environnementaux. Nous en abordons deux aspects, à travers deux contextes distincts d'application.En lien avec la simulation des écoulements en milieux poreux, on s'intéresse dans une première partie à la discrétisation d'opérateurs de diffusion anisotropes hétérogènes par des méthodes de volumes finis sur des maillages généraux. Dans le but d'obtenir des solutions approchées qui respectent les bornes physiques des modèles, notre attention se porte sur la conservation du principe du maximum pour les opérateurs elliptiques. Nous présentons des mécanismes généraux permettant de corriger tout schéma volumes finis afin de garantir un principe du maximum discret tout en préservant certaines de ses propriétés principales. On étudie en particulier les propriétés de coercivité et de convergence des schémas corrigés.La deuxième partie est consacrée à la construction de modèles approchés pour la propagation des vagues en eaux peu profondes et sur des topographies irrégulières. A cet effet, nous proposons tout d'abord une adaptation de la démarche d'étude classique à des écoulements bidimensionnels sur des topographies polygonales. Dans un cadre plus général, nous développons ensuite une démarche formelle qui débouche sur des alternatives non locales à quelques modèles classiques (équations de Saint-Venant, équations de Serre, système de Boussinesq). Ces nouveaux modèles contiennent des termes régularisants pour les contributions du fond.
10

Stereotypical behaviour in the deer mouse (Peromyscus Maniculatus bairdii) : a pharmacological investigation of the frontal–cortico–striatal serotonergic system / Wolmarans D.

Wolmarans, Petrus De Wet January 2011 (has links)
Obsessive–compulsive disorder (OCD) is a psychiatric condition that is characterized by two main symptom cohorts, namely recurrent inappropriate thoughts (obsessions) and seemingly purposeless repetitive motor actions (compulsions). In 70% of cases, the condition only re–sponds to chronic, but not sub–chronic, high dose treatment with the selective serotonin reup–take inhibitors (SSRIs), such as fluoxetine and escitalopram. This indicates a role for hyposero–tonergic functioning in the primary brain areas involved in OCD, namely the components of the cortico–striatal–thalamic–cortical (CSTC) circuit which include the prefrontal cortex, the basal ganglia, and the thalamus. A number of studies have demonstrated a lower serotonin trans–porter (SERT) availability in OCD patients compared with healthy controls, supporting the hy–pothesis of a hyposerotonergic state in OCD. The current study focuses on the validation of the deer mouse (Peromyscus maniculatus bairdii) model of OCD and builds on previous work done in our laboratory. Deer mice that are bred and housed in confinement naturally develop two main forms of stereotypical behaviour, namely vertical jumping and pattern running. Furthermore, these behaviours can be catego–rized into various levels of severity, namely high (HSB), low (LSB) and non–stereotypic (NSB) cohorts. The seemingly purposeless and repetitive nature of these behaviours mimics the com–pulsions that characterize human OCD and constitutes the basis for the face validity of the model. However, although these two forms of stereotypy seem equally repetitive and persis–tent, stereotypical pattern runners do not complete the required number of cage revolutions per 30 minutes compared to the amount of jumps executed by stereotypical vertical jumpers. As only one set of criteria for the appraisal of the different topographies of deer mouse stereotypy has been applied in previous studies, the matter of whether pattern runners do in fact generate stereotypical behaviour of the same persistent and severe nature as opposed to the behaviour expressed by vertical jumpers, is problematic. Therefore, the first objective of the current study was to develop a new classification system for the appraisal of the different forms of behavioural topographies of deer mice and subse–quently to evaluate whether pattern runners can indeed be categorized into non–, low– and high stereotypical cohorts. After an eight–week behavioural assessment period, deer mice express–ing the two different behavioural topographies could be classified into non–, low– and high stereotypical cohorts (NSB, LSB, and HSB respectively), applying different criteria for each be–havioural topography. Based on the weekly mean stereotypy count generated during three 30–minute intervals of highest stereotypical behaviour over the course of a 12–hour assessment period, HSB pattern runners were found to execute on average 296 cage revolutions per 30 minutes, while HSB vertical jumpers executed an average of 3063 jumps per 30 minutes. This discrepancy between the generated numbers of the different topographies of stereotypy indi–cates that one classification system for the appraisal of both behavioural topographies is indeed inappropriate, and hence requires re–evaluation and validation. As patients with OCD present with a lower central SERT availability compared to healthy controls, the second objective of the study was to determine whether a decrease in SERT den–sity could be demonstrated in HSB animals compared to the NSB and LSB controls. After eight weeks of behavioural assessment, animals were sacrificed and frontal–cortical and striatal SERT binding was performed. HSB deer mice presented with significantly lower striatal, but not fron–tal–cortical SERT availability compared to the [NSB/LSB] control animals (p = 0.0009). As far as it concerns a lower SERT availability in HSB animals and involvement of the CSTC circuitry, this data is congruent with that demonstrated in human OCD and strengthens the construct validity of the model. Although previous studies undertaken in our laboratory demonstrated that deer mouse stereotypy is attenuated after chronic (21–day) fluoxetine administration, OCD only responds to chronic, but not sub–chronic treatment with the SSRIs. The lack of response of deer mouse stereotypy to sub–chronic treatment has not been established and therefore the third study ob–jective was to assess the behavioural effects of sub–chronic (7–day) and chronic (28–day) SSRI treatment on expression of deer mouse stereotypy. Chronic, but not sub–chronic treatment with oral escitalopram (50 mg/kg/day) significantly increased the number of intervals over a 12–hour assessment period during which no stereotypical behaviour were expressed by HSB deer mice (p = 0.0241) and decreased the number of intervals during which high–stereotypical be–haviour were executed (p = 0.0054). Neither chronic, nor sub–chronic treatment significantly affected the behaviour of animals in the [NSB/LSB] cohort. The fact that the model demon–strates a lack of response to sub–chronic treatment with high dose SSRIs, positively contributes to the predictive validity of the deer mouse model of OCD. The results from the current study therefore strengthens the construct and predictive valid–ity of the deer mouse model of OCD and confirm the model’s status as a prominent animal model of OCD. Not only is hyposerotonergic functioning in the CSTC circuitry implicated in the behaviour of HSB animals, but the model also demonstrates selective response to chronic SSRI–treatment - two core characteristics of human OCD. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2012.

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