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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.
81

Between the 'sectional' and the 'national' : oil, grassroots discontent and civic discourse in Nigeria

Akpan, Wilson Ndarake January 2006 (has links)
This thesis examines the social character of petroleum-related grassroots struggles in Nigeria’s oil-producing region. It does this against the background of the dominant scholarly narratives that portray the struggles as: a) a disguised pursuit of an ethnic/sectional agenda, b) a 'minority rights' project, and c) a minority province’s protest against 'selective' environmental 'victimisation' by the majority ethnic nationalities. While the dominant scholarly analyses of the struggles are based on the activities of the better known activist organisations operating in the oil region, this thesis focuses primarily on the everyday 'grammar' of discontent and lived worlds of ordinary people vis-à-vis upstream petroleum operations and petroleum resource utilisation. The aim has been to gain an understanding of the forces driving community struggles in the oil region and their wider societal significance. Examined alongside the narratives of ordinary people are the legal/institutional framework for upstream petroleum operations and the operational practices of the oil-producing companies. Using primary data obtained through ethnography, focus group discussions, in-depth interviews and visual sociology, as well as relevant secondary data, the researcher constructs a discourse matrix, showing how grassroots narratives in selected oilproducing communities intersect with contemporary civic discourses in the wider Nigerian context. The thesis highlights the theoretical and policy difficulties that arise when the social basis of petroleum-related grassroots struggles and ordinary people’s narratives are explained using an essentialist idiom. It reveals, above all, the conditions under which so-called 'locale-specific' struggles in a multi-ethnic, oil-rich African country can become a campaign for the emancipation of ordinary people in the wider society. This research extends the existing knowledge on citizen mobilisation, extractive capitalism, transnational corporate behaviour, and Nigeria’s contemporary development predicament. It sheds light on some of the processes through which ordinary people are forcing upon the state a change agenda that could drive the country along a more socially sensitive development and democratisation trajectory.
82

Integrative Konzipierung von Produkt und Produktionssystem als Basis für eine erfolgreiche Produktentstehung

Gausemeier, Jürgen, Tschirner, Christian, Gaukstern, Tobias, Dumitrescu, Roman 26 September 2017 (has links) (PDF)
Aus der Einleitung: "Maschinenbauliche Systeme beruhen heute vielfach auf einem engen Zusammenwirken von Mechanik, Elektrotechnik/Elektronik, Regelungstechnik und Softwaretechnik. Über die Mechatronik hinausgehend werden sie eine inhärente Intelligenz aufweisen und damit Produktfunktionen ermöglichen, die bislang nur von biologischen Systemen bekannt sind. Begriffe wie Intelligente Objekte, Cyber-Physical Systems und Selbstoptimierung charakterisieren diese Perspektive (acatech 2009, 2011, Broy & Geisberg 2012, Adelt et al. 2009). Sie werden sich selbstständig und flexibel an wechselnde Betriebs- bzw. Umgebungsbedingungen anpassen können. Die Entwicklung derartiger Systeme kann nicht aus dem Blickwinkel einer Disziplin allein vorgenommen werden. Das gilt sowohl für mechatronische als auch für intelligente technische Systeme. Daher ist schon frühzeitig ein fachdisziplinübergreifendes Konzept zu erarbeiten, das den grundsätzlichen Aufbau und die Wirkungsweise des Systems beschreibt und die Grundlage für die etablierten Ansätze der Entwurfs- und Ausarbeitungsphase bildet, wie z.B. die VDI-Richtlinie 2221 (Verein Deutscher Ingenieure 1993) oder das Y-Modell der Schaltungstechnik (Bleck et al. 1996)."
83

Use of Distance Weighted Metrics to Investigate Landscape-Stream Temperature Relationships Across Different Temporal Scales

Watson, Eric Craig 16 August 2016 (has links)
Stream ecosystems have experienced significant negative impacts from land use, resource exploitation, and urban development. Statistical models allow researchers to explore the relationships between these landscape variables and stream conditions. Weighting the relevant landscape variables based on hydrologically defined distances offers a potential method of increasing the predictive capacity of statistical models. Using observations from three grouped watersheds in the Portland Metro Area (n=66), I have explored the use of three different weighting schemes against the standard method of taking an areal average. These four different model groups were applied to four stream temperature metrics: mean seven-day moving average maximum daily temperature (Mean7dTmax), number of days exceeding 17.8 °C (Tmax7d>17.8), mean daily range in stream temperature (Range_DTR), and the coefficient of variation in maximum daily temperature (CV_Tmax). These metrics were quantified for the 2011 dry season. The strength of these model groups were also examined at a monthly basis for each of the four months within the dry season. The results demonstrate mixed effectiveness of the weighting schemes, dependent on both the stream temperature metric being predicted as well as the time scale under investigation. Models for Mean7dTmax showed no benefit from the inclusion of distance weighted metrics, while models for Range_DTR consistently improved using distance weighted explanatory variables. Trends in the models for 7dTmax>17.8 and CV_Tmax varied based on temporal scale. Additionally, all model groups demonstrated greater explanatory power in early summer months than in late summer months.
84

Between Logos and Eros: New Orleans' Confrontation with Modernity

Moore, Erin Christine 05 1900 (has links)
This thesis examines the environmental and social consequences of maintaining the artificial divide between thinking and feeling, mind and matter, logos and eros. New Orleans, a city where the natural environment and human sensuality are both dominant forces, is used as a case study to explore the implications of our attempts to impose rational controls on nature - both physical and human nature. An analysis of New Orleans leading up to and immediately following Hurricane Katrina (2005) reveals that the root of the trouble in the city is not primarily environmental, technological, political, or sociological, but philosophical: there is something amiss in the relationship between human rationality and the corporeal world. I argue that policy decisions which do not include the contributions of experts from the humanities and qualitative social sciences - persons with expertise on human emotions, intentions, priorities and desires - will continue to be severely compromised.
85

EVALUATING UNMANNED AIRCRAFT SYSTEM PHOTOGRAMMETRY FOR COASTAL FLORIDA EVERGLADES RESTORATION AND MANAGEMENT

Unknown Date (has links)
The Florida Everglades ecosystem is experiencing increasing threats from anthropogenic modification of water flow, spread of invasive species, sea level rise (SLR), and more frequent and/or intense hurricanes. Restoration efforts aimed at rehabilitating these ongoing and future disturbances are currently underway through the implementation of the Comprehensive Everglades Restoration Plan (CERP). Efficacy of these restoration activities can be further improved with accurate and site-specific information on the current state of the coastal wetland habitats. In order to produce such assessments, digital datasets of the appropriate accuracy and scale are needed. These datasets include orthoimagery to delineate wetland areas and map vegetation cover as well as accurate 3-dimensional (3-D) models to characterize hydrology, physiochemistry, and habitat vulnerability. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
86

Integrative Konzipierung von Produkt und Produktionssystem als Basis für eine erfolgreiche Produktentstehung

Gausemeier, Jürgen, Tschirner, Christian, Gaukstern, Tobias, Dumitrescu, Roman January 2012 (has links)
Aus der Einleitung: "Maschinenbauliche Systeme beruhen heute vielfach auf einem engen Zusammenwirken von Mechanik, Elektrotechnik/Elektronik, Regelungstechnik und Softwaretechnik. Über die Mechatronik hinausgehend werden sie eine inhärente Intelligenz aufweisen und damit Produktfunktionen ermöglichen, die bislang nur von biologischen Systemen bekannt sind. Begriffe wie Intelligente Objekte, Cyber-Physical Systems und Selbstoptimierung charakterisieren diese Perspektive (acatech 2009, 2011, Broy & Geisberg 2012, Adelt et al. 2009). Sie werden sich selbstständig und flexibel an wechselnde Betriebs- bzw. Umgebungsbedingungen anpassen können. Die Entwicklung derartiger Systeme kann nicht aus dem Blickwinkel einer Disziplin allein vorgenommen werden. Das gilt sowohl für mechatronische als auch für intelligente technische Systeme. Daher ist schon frühzeitig ein fachdisziplinübergreifendes Konzept zu erarbeiten, das den grundsätzlichen Aufbau und die Wirkungsweise des Systems beschreibt und die Grundlage für die etablierten Ansätze der Entwurfs- und Ausarbeitungsphase bildet, wie z.B. die VDI-Richtlinie 2221 (Verein Deutscher Ingenieure 1993) oder das Y-Modell der Schaltungstechnik (Bleck et al. 1996)."
87

Structural Health Monitoring of Bridges using Machine Learning : The influence of Temperature on the health prediction

Khouri Chalouhi, Elisa January 2016 (has links)
A method that uses machine learning to detect and localize damage in railway bridges under various environmental conditions is proposed and validated in this work. The developed algorithm uses vertical and lateral deck accelerations as damage- sensitive features. Indeed, an Artificial Neural Network (ANN) is trained to predict deck accelerations in undamaged condition given: previous vibration data, air temperature and characteristics of the train crossing the bridge (speed, load position and load magnitude). After an appropriate training period, the comparison between ANN-predicted and measured accelerations allows to compute prediction errors. A Gaussian Process is then used to stochastically characterize prediction errors in undamaged conditions using train speed as independent variable. Recorded vibration data leading to abnormal prediction errors are flagged as damage. The method is validated both on a simple numerical example and on data recorded on a real structure. In the latter case, an appropriate algorithm was developed with the aim of extracting vehicles characteristics from the acceleration time histories. Together with this part of the algorithm for the pre-processing of recorded accelerations, the novelty of the developed method is the addition of air temperature to the input. It allows separating between structure responses that can be flagged as damage from those only affected by environmental conditions.
88

Writing the environmental history of the Yellow River region from the Zhou to the Han : sources and methodological problems

Lander, Brian. January 2006 (has links)
No description available.
89

Estimating fugitive process emissions at Kennedy Space Center

Lopez, Esteban R. 01 April 2000 (has links)
No description available.
90

Enviromental factors affecting the pathogenesis of Edwardsiella ictaluri in striped catfish Pangasianodon hypophthalmus (Sauvage)

Nguyen, Ngoc Phuoc January 2014 (has links)
Bacillary Necrosis of Pangasius (BNP) caused by Edwardsiella ictaluri is considered to be the most serious disease occurring in farmed striped catfish (Pangasianodon hypophthalmus) in Vietnam. This disease has had an increasing impact over the last ten years and has been reported to cause 50-90% mortality of stocks during a single outbreak. Data obtained from natural outbreaks of E. ictaluri in striped catfish showed the role of environmental factors in the establishment and progression of this disease. At present, factors affecting the virulence and transmission of E. ictaluri in striped catfish are poorly understood. The central hypothesis of this thesis focuses on the complex picture of the environmental factors and infectivity of E. ictaluri in striped catfish. In this study, 80 isolates of E. ictaluri recovered from natural clinical disease outbreaks occurring in striped catfish farms between 2002 and 2011 located in 4 distinct geographical areas within Vietnam were characterised using a variety of methods. The biochemical profiles showed that E. ictaluri isolates from striped catfish in Vietnam have similar phenotypic characteristics to other E. ictaluri isolates from other infected fish species. These data showed high levels of phenotypic homogeneity between the E. ictaluri isolates investigated. The status of isolates recovered from natural infections over time and from geographically distinct farms was evaluated using pulsed-field gel electrophoresis (PFGE), plasmid profile identification and antibiotic sensitivity tests. The PFGE results showed 6 main groups with a similarity of 82% and the corresponding genotypes of the prevalent isolates illustrated annual differences. Three plasmid groups were identified distributed among the isolates investigated, in which high molecular weight plasmids of approximately 35 and 140 kb were found in two of the groups. Plasmid profiles of the present study did not show any trend of geographical region or year of isolation. The 140 kb plasmid has been considered as a multi-antibiotic resistance plasmid which confers resistance to tetracycline, trimethoprim and sulphonamides. All Vietnamese isolates showed a high level of resistance to Oxolinic acid, Sulfadimethoxine/Ormetoprim (Romet), Oxytetracycline and Amoxicillin. A reproducible bacterial immersion challenge model was developed and the LD60 estimated prior to performing subsequent experimental challenge studies. Fish were exposed to 107 cfu ml-1 of E. ictaluri by immersion for up to 30 seconds, resulting in a cumulative percentage mortality of 63%. Edwardsiella ictaluri was recovered and identified from all the dead and moribund fish during these experiments and affected fish showed similar clinical signs and pathology to those reported from natural E. ictaluri infections. The present study resulted in a successful experimental immersion challenge model for E. ictaluri infection in healthy striped catfish. Cohabitation challenges were also developed and produced 15-40% mortality, typical clinical signs and pathology, and successful recovery of the challenge organism demonstrating horizontal transmission of E. ictaluri in striped catfish. Experimental studies were then conducted to investigate the association between pH or salinity of water and susceptibility to E. ictaluri infection in striped catfish. The first experiments were performed in in vitro conditions in which E. ictaluri isolates were cultured in a variety of pH and salt concentrations. In vivo experiments were then designed where striped catfish were exposed to 107 cfu ml-1 of E. ictaluri for 30 seconds and then held at 4 different water pHs (5.5, 6.5, 7.5 and 8.5) or NaCl concentrations (0, 0.5, 1 and 1.5%). The results of in vitro experiments showed that a pH value between 5.5 to 6.5 and salt concentration between 0-0.5% were optimal for the growth of E. ictaluri. The in vivo experiments demonstrated that the cumulative mortality of striped catfish in water at pH 5 and pH 6 was significantly higher than that of fish maintained in more alkaline water (p<0.05). By contrast, the cumulative mortality of the striped catfish maintained in 0.5% salt concentration was significantly lower than those kept in 0%, 1% and 1.5% salt concentration (p<0.05). Clinical signs, lesions and histopathological changes in the affected fish were consistent with those reported in natural infections. This study highlighted the use of pH 8.5 and salinity of 0.5% NaCl as a means of decreasing the susceptibility of striped catfish to E. ictaluri. In conclusion, this study used a variety of methods in order to enhance the understanding of the biochemical, biophysical characteristics, plasmid profile and antibiotic resistance as well as the relatedness of E. ictaluri isolates recovered from farmed striped catfish in Vietnam. This study provided two reliable and reproducible bacterial challenge models (immersion and cohabitation) and emphasised the link between pH and salinity with the infectivity and pathogenicity of E. ictaluri in striped catfish.

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