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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

Evaluating and updating the Kansas Department of Transportation’s lane closure guide in the Kansas City metropolitan area using Traffic Management Center data

Nye, Benjamin Gilbert January 1900 (has links)
Master of Science / Department of Civil Engineering / Eric J. Fitzsimmons / Each year maintenance and rehabilitation occur on interstates and highways to repair damage, improve rideability, and increase safety. To perform many of these activities a short or long-term work zone is required. However, short and long-term work zones can have significant impacts on traffic flow, especially during peak travel times. To mitigate the impact of work zones, the Kansas Department of Transportation (KDOT) has developed a lane closure guide to assist KDOT personnel and contractors in determining times during the day that a lane can be closed to traffic. The existing lane closure guide was comprised of limited data sources and assumptions based on past traffic counts. The purpose of this research study was to evaluate the existing guide and update it using a consistent data source that reflects current roadway conditions. During the evaluation of the existing lane closure guide, several inconsistencies with traffic counts, directional splits, and adjustment factors were found. To eliminate the consistencies, data from the Kansas City Traffic Management Center was used. During the procedure of updating the lane closure guide a repeatable data extraction process and a quality assurance/quality control process were utilized. In addition to updating the KDOT lane closure guide, sensor data verification was performed on one KC Scout sensor on K-10 using road tubes. The data from the road tubes was then compared to the data extracted from KC Scout during the same time interval. The comparison found the road tubes and KC Scout counted statistically the same number of cars for the chosen interval. However, the comparison found the road tube’s average speed for chosen interval to be on average 10 percent higher than KC Scout, which was statistically significant.
132

Improving our Understanding of Source Zones at Petroleum Impacted Sites through Physical Model Studies

January 2014 (has links)
abstract: Characterization of petroleum spill site source zones directly influences the selection of corrective action plans and frequently affects the success of remediation efforts. For example, simply knowing whether or not nonaqueous phase liquid (NAPL) is present, or if there is chemical storage in less hydraulically accessible regions, will influence corrective action planning. The overarching objective of this study was to assess if macroscopic source zone features can be inferred from dissolved concentration vs. time data. Laboratory-scale physical model studies were conducted for idealized sources; defined as Type-1) NAPL-impacted high permeability zones, Type-2) NAPL-impacted lower permeability zones, and Type-3) dissolved chemical matrix storage in lower permeability zones. Aquifer source release studies were conducted using two-dimensional stainless steel flow-through tanks outfitted with sampling ports for the monitoring of effluent concentrations and flow rates. An idealized NAPL mixture of key gasoline components was used to create the NAPL source zones, and dissolved sources were created using aqueous solutions having concentrations similar to water in equilibrium with the NAPL sources. The average linear velocity was controlled by pumping to be about 2 ft/d, and dissolved effluent concentrations were monitored daily. The Type-1 experiment resulted in a source signature similar to that expected for a relatively well-mixed NAPL source, with dissolved concentrations dependent on chemical solubility and initial mass fraction. The Type-2 and Type-3 experiments were conducted for 320 d and 190 d respectively. Unlike the Type-1 experiment, the concentration vs. time behavior was similar for all chemicals, for both source types. The magnitudes of the effluent concentrations varied between the Type-2 and Type-3 experiments, and were related to the hydrocarbon source mass. A fourth physical model experiment was performed to identify differences between ideal equilibrium behavior and the source concentration vs. time behavior observed in the tank experiments. Screening-level mathematical models predicted the general behavior observed in the experiments. The results of these studies suggest that dissolved concentration vs. time data can be used to distinguish between Type-1 sources in transmissive zones and Type-2 and Type-3 sources in lower permeability zones, provided that many years to decades of data are available. The results also suggest that concentration vs. time data alone will be insufficient to distinguish between NAPL and dissolved-phase storage sources in lower permeability regions. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2014
133

Exploitation of non-living marine resources within national jurisdiction in East Africa

Ntola, Yamkela Siqhamo January 2015 (has links)
This dissertation involves an analysis and discussion of the legal regime governing the exploitation of non-living marine resources within national jurisdiction in East Africa. This is in light of the relatively recent offshore oil and gas discoveries off the coasts of Mozambique and Tanzania which have resulted in offshore exploration activities along the Western Indian Ocean (including the Red Sea) in pursuit of these hydrocarbons. Before delving into legal analysis and discussion, the dissertation departs by providing background on the 1982 United Nations Law of the Sea Convention (LOSC)2 which is the international legal regime governing maritime spaces and the contributions made by, inter alia, East African coastal States to bring it about. From here, the dissertation ventures into an analysis and discussion of the legal zones claimed by East African coastal States within which exploitation activities may occur. This part of the discussion involves, among other things, an in depth analysis of the practices of East African coastal States as far as establishing maritime zones in terms of international law. The dissertation then proceeds to discuss which East African coastal States have delimited their maritime zones where they overlap with neighbouring States with adjacent and/or opposite coasts. The discussion highlights which States, in terms of international law, have clearly defined the ambit of their maritime jurisdiction by establishing a delimitation boundary where claims to maritime zones overlapped. This part of the dissertation also discusses which States have not delimited their overlapping maritime zones and the reasons for the lack of delimitation. Following this, the dissertation moves on to discuss the LOSC provisions applicable to exploiting non-living resources, and analyse whether the laws of East African coastal States that pertain to exploiting these resources adequately give effect to LOSC. Finally, in light of the above analysis and discussions, the dissertation moves on to establish if whether or not the legal infrastructure of East African coastal States is adequate for exploiting non-living resources within their national jurisdiction. Generally, the findings reflect favourably on the legal framework of East African coastal States. However, the pressing issue is the practices of some States in respect of claiming certain maritime zones and where necessary, not delimiting these zones. This results in uncertainty as to the maritime jurisdiction of a coastal State, especially with resources such as oil and gas which may straddle across boundaries. Moreover, it creates conflict and as such, threatens peace and security in the region as well as stunt economic and socio-economic development. As such, this dissertation, on the one hand, reflects the advancement of East African coastal States from contributing towards the adoption and coming into effect of LOSC, as well as giving effect to it domestically as far as exploiting non-living resources within national jurisdiction is concerned. On the other hand, it highlights the work that lays ahead for East African coastal States in order for them to fully enjoy their right.
134

Post Alpine tectonic evolution of S.E. Spain and the structure of fault gouges

Hall, Stephen Howard January 1983 (has links)
No description available.
135

Investigation of Transpressive Deformation Zones in the North Caribou Greenstone Belt (NW Superior) and Relationships with Regional Metamorphism: Implications for the Technothermal Evolution during Archean Cratonization

Gagnon, Émilie January 2015 (has links)
The Archean North Caribou greenstone belt (NCGB) possesses abundant transpressive deformation zones on its northern margins, which appear to have formed under amphibolite facies conditions. Protracted deformation and regional metamorphism are coeval with widespread magmatism and accretion events in the Superior Province, yet the importance of these shear zones in the tectonic evolution of the NCGB is equivocal. Structural analyses support a transpressive system that strongly implicates horizontal tectonism. This is partly in contrast with some currently proposed models for Archean greenstone belts suggesting synchronous vertical and horizontal movements. Geochemical and microstructural analyses from shear zones indicate heterogeneous deformation/fluids conditions on a km-scale. Monazite and mica geochronological ages indicate metamorphism and deformation occurring during the amalgamation of the Superior craton from ca. 2.75 to 2.4 Ga. The high metamorphic grade background may obscure tectonic signatures, yet some structural and geochemical characteristics remain consistent with other greenstone belts where vertical and horizontal displacement are recorded.
136

Une inondation négociée ? Politisation d'un risque naturel sur le Rhône / Negotiating flood risk ? Politics of a natural risk management on the Rhône River (France)

Guerrin, Joana 11 December 2014 (has links)
Depuis les années 1990, un changement semble être intervenu dans les politiques du risque inondation en France. Les aménagements de protection qui prévalaient depuis le XIXe siècle ont été remis en cause et l'inondation a été requalifiée comme un phénomène inévitable voire bénéfique pour l'environnement. Les discours de politique publique relatifs à la culture du risque ont remplacé ceux présentant le risque inondation comme un enjeu de sécurité publique. Les instruments d'action publique ont également changé. Les aménagements visant à inciter les riverains à vivre avec le risque inondation ont succédé à la construction de digues de protection. Notre thèse questionne la portée de ce changement d'action publique dans le domaine du risque inondation à travers l'étude d'une politique territoriale sur le Rhône. À cette fin, nous retraçons la genèse d'un instrument d'action publique, la restauration de zones d'expansion de crues, dans les forums internationaux et européens. Nous rendons compte de la traduction de cet instrument opérée sur le Rhône par une coalition de réformateurs promouvant une nouvelle problématisation des inondations. Nous suivons les controverses qui se sont déployées autour de la mise en œuvre de cet instrument localement, qui sont autant de traductions concurrentes de ce dernier. Enfin, nous questionnons les effets de l'abandon de cet instrument sur la politique territoriale, sur l'institution qui l'a porté, et sur le changement d'action publique annoncé. / Since the 1990s a shift occurred in the policies of flood risk in France. The protection structures that had been prevailing since the 19th century were questioned, and flooding was redefined as an unavoidable and beneficial for the environment. Public policy discourses about risk culture have replaced those of flood risk as an issue of public safety. The policy instruments have also changed. Facilities to encourage residents to live with flooding replaced major dykes building. The thesis questions the extent of this policy shift in the field of flood risk through the study of a local policy on the Rhône River. To that end, we retrace in international and European fora the origin of a policy instrument typical of this policy shift: the restoration of floodplains. We analyze the adaptation of this instrument to the Rhône as an opportunity for a coalition to support a new definition of floods locally. We follow the controversies and conflicts that developed around the implementation of this instrument. Finally, we question the impact of the abandonment of this instrument on the local policy itself, on the legitimacy of the coalition and on the policy shift announced.
137

Effekten av kantzoners bredd på terrestra evertebraters nedfall till skogliga vattendrag / Effects of riparian buffer width on terrestrial invertebrate input to forest streams

Karlsson, Jeanette January 2021 (has links)
Kantzoner längst vattendrag i skogen är en komplex och artrik miljö som är av stor vikt för flertalet arter. Ett stort hot mot kantzoner är skogsindustrin och främst kalavverkning som kan ha en negativ effekt på hela ekosystem. Det finns idag ingen lag som kräver att kantzoner längst vattendrag bevaras med det rekommenderas. En kalavverkning kan minska tillförsel av nedfall som terrestra invertebrater till vattendraget med så mycket som en tredjedel, även om en kantzon på 30 meter bevaras. Tillförsel av terrestra invertebrater till vattendragen är av stor vikt då det kan utgöra upp till 50% av energiintaget hos fisk. Frånvaro av terrestra invertebrater skulle kunna leda till en ökad biomassa av perifyton och en minskad tillväxt hos fisk. För att undersöka om kantzonernas bredd längst vattendrag i skogen påverkar nedfallet av invertebrater till vattendraget genomförs en fältstudie. 17 lokaler har besökts i studien där fällor placerats ut på två ställen längst en 100 meters sträcka. Fällornas innehåll sorterades sedan till ordning. Krontäckningen kontrollerades även på varje lokal och vegetationen inventerades. Regressionsanalys, HCA, PCA och korrelationsanalys utfördes. Efter analys indikerade resultatet på att det är vegetationens sammansättning som är den viktigaste faktorn. Lokaler med mycket örter och bar jord hade en större förekomst av individer och ordningar. Detta kan bero på att ett kalhygge släpper in mer ljus och värme. Avverkade områden kan ha högre näringsvärde vilket kan gynna flertalet arter. Lokalerna som besöktes i studien var förhållandevis ung produktionsskog vilket kan även ha spelat in då dessa skogar har en relativt låg biodiversitet. Vid planering och konstruktion av kantzoner längst skogliga vattendrag bör det prioriteras att skapa kantzoner av god ekologisk status. / Riparian forests is a complex and species-rich environment that is of great importance for many species. A big threat to the riparian forests is the forest industry and mainly clear-cut felling, which can have a negative effect on entire ecosystems. There is currently no law that requires that buffer zones along forest streams be preserved, it is however recommended. A clear cut can reduce the input of to the stream by as much as a third, even if a buffer zone of 30 meters is preserved. The input of terrestrial invertebrates to streams is of great importance as it can account for up to 50% of the energy intake of fish. An absence of terrestrial invertebrates could lead to increased periphyton biomass and reduced growth in fish. A field study was performed to investigate if the buffer width effects the input of terrestrial invertebrates. 17 sites were visited where traps were placed at two placed along a 100 stretch. The content of the traps was then sorted into order. The canopy cover was controlled, and the vegetation was inventoried. Regression analysis, HCA, PCA and correlation analysis was performed. After analysis, the results indicated that it is the composition of the vegetation that is the most important factor. Sites with a lot of herbs and bare soil had a greater presence of individuals and orders. This may be because clear cuts let in mor e light and heat, they can also have a higher nutritional value which can benefit several species. The sites visited in the study were relatively young production forest which also may have played a role as these forests have a relatively low biodiversity. When planning and constructing buffer zones along forest streams, it should be prioritized to creating buffer zones of good ecological status.
138

Spatial Heterogeneities of Warming Impacts on Corn Yields in Ghana

Ofori, Eric Kwesi Makafui 11 August 2017 (has links)
Climate change impacts on agriculture have been widely researched in recent years. In Sub-Saharan Africa, many of these studies have focused on spatially aggregate impacts at the country or higher level, and typically do not discuss the heterogeneities of impacts within a region. Thus, there is a growing interest in more localized climate change impacts modeling that could help inform regional adaptation within a country. In this study, we utilize a panel of Ghanaian subnational district-level corn yields matched to weather data that is spatially interpolated from observed station data to identify whether warming impacts exhibit spatial heterogeneities for corn yields. Findings show spatial heterogeneities of yields across main and non-main corn growing areas, as well as various ecological zones and also at the district level. Furthermore, findings indicate that extremely high temperature would have negative impacts on yields in main corn-growing areas, meanwhile, impacts are expected to be insignificant in non-main corn growing areas. This study will be helpful in informing future research as well as food security and stability adaptation decisions related to climate change in Ghana. Keywords: corn, yields, climate, change, zones, Ghana
139

Magnetic compression of axially symmetric Brillouin-focused electron beams /

Seeger, John Alan January 1966 (has links)
No description available.
140

Troubling Literacy in the "Contact Zone" of a Rural High School English Class

Groenke, Susan Lee 02 September 2003 (has links)
This dissertation examines how multiple, hybridized literacy practices exist in the "contact zone" of the classroom, a "social space where cultures meet, clash, and grapple, with each other, often in contexts of highly asymmetrical relations of power, such as colonialism, slavery, or their aftermaths as they are lived out in many parts of the world today" (Pratt, 2002, p. 4). The rural high school English class under study here operates as such a "contact zone," as the teacher and students engage in conflicted negotiation, rather than assimilation or acculturation, when multiple literacy practices vie for recognition. Fieldnotes collected during two months of participant observation, collected artifacts in the form of student written texts, teacher syllabi and school documents, i.e., student handbooks, as well as interviews with three male students, one female student, one teacher, one special education aide, and a school principal provided the data for this study. Findings make problematic the beliefs that 1) literacy is a homogenous, static, singular either/or phenomenon, i.e., official school literacy or unofficial, and that 2) classrooms represent homogeneous, unified communities of obedient students who share literacy practices. Rather, classrooms, as "contact zones," can represent heterogeneous groups of students whose literacy practices are hybrid and intercultural, grafting together often reactionary, oppressive sociopolitical intentions with officially sanctioned literacy goals. This inquiry raises questions about literacy as only a local social practice, as well as literacy pedagogical discourses that students do not simply assimilate or acculturate, but contest, appropriate, resist, and use to harass and oppress others, even as they accomplish school literacy assignments. / Ph. D.

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