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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.
161

Paleoecology of the Freshwater Ampullariidae from the Late Oligocene Nsungwe Formation of Tanzania

Epa, Yuwan Ranjeev 13 June 2017 (has links)
No description available.
162

MAVS is Essential for Regulation of Innate Immune Signaling during Rift Valley Fever Virus Infection

Ermler, Megan Elizabeth 21 February 2014 (has links)
No description available.
163

Age, Origin and Mineral Resources of the Sams Creek/Wakefield Complex, Maryland Piedmont

Graybill, Elizabeth A. 25 July 2012 (has links)
No description available.
164

Gender and Land Grabbing - A post-colonial feminist discussion about the consequences of land grabbing in Rift Valley Kenya

Zetterlund, Ylva January 2013 (has links)
This study has the aim to analyze what impacts land grabbing in Rift Valley, Kenya, has on rural poor, as it is perceived from a gendered perspective. Land acquisitions, or land grabbing, is a growing global phenomenon, where companies and states (foreign and domestic) are claiming land for investments, to secure the growing demand for food and biofuels, with neg-ative impacts on the rural population. Most exposed are the rural poor women. The gender issue is however not analyzed in a proper way in the debate, which is why study is important.In Rift Valley, Kenya the situation is slightly different with domestic actors standing behind the grabs. The consequences are nonetheless felt by the rural poor population, especially by the women. Through field studies and interviews with women exposed to the phenomenon I have found that even though legislation exists to provide human rights, these are often violat-ed on the ground. Women’s experiences are examined and together with other first- and sec-ondary sources these are analyzed with the theoretical lens of post-colonial feminism and the capabilities approach, leading to the conclusion that women are more vulnerable for land grabs but are capable actors fighting to make their lives better.
165

Delineating the geometry of the Central Metasedimentary Belt Boundary Zone of the Grenville Province: Nd isotope evidence of a failed back-arc rift zone between Minden and Bancroft, Ontario

Moretton, Katherine 08 1900 (has links)
<p> The Grenville Province represents the remains of a collisional orogeny ca. 1.2 - 1.0 Ga and contains the Central Metasedimentary Belt (CMB). Generally thought to represent one or more accreted island arcs, the CMB is located between belts of highgrade gneisses and contains a number of identified structural terranes. Neodymium (Nd) model ages of the high-grade gneisses on either side of the CMB yield similar values (~1.5 Ga) while the average model age within the CMB is usually more juvenile (<1.3 Ga). This distinction, along with observations about the geometrical shape of the juvenile zone, has led to the creation of an alternative model for the development of the CMB in the Grenville Province as developed by Dickin and McNutt, (2007). The new model equates the CMB with an ensimatic rift zone with an en echelon morphology consisting of a series of segments with NNE trends, separated by one or more horsts of older crustal rock. The development of the CMB under these conditions implies that restricted access to seawater may have facilitated limestone deposition prior to major biogenic influences, and thus the morphology of the rift is defined in part by the extent of the Grenville marble outcrops. </p> <p> The present study tests this model through the use of 80 new Nd isotope analyses to map the NW boundary of the CMB, known as the Central Metasedimentary Belt Boundary Zone (CMBBZ), west of Bancroft, Ontario. Within this part of the CMBBZ, the age boundary between pre-Grenvillian and juvenile gneisses is relatively sharp (1 - 4 km wide) and this age boundary makes a near 90-degree tum from a NNE trend near Minden to an E-W trend near Haliburton. Two blocks of older material are located within the juvenile terranes of the CMB, which are interpreted as being blocks of older crust rifted from the walls of the older Muskoka domain to the north of the study region. These structures are analogous to similar horsts of older crustal material found in the Afar region of East Africa. Therefore, we suggest that the locus of the CMBBZ was constrained by older structures, representing a transition from the side of a rift zone segment south of Minden, to the truncated end of this rift segment between Haliburton and Bancroft. Hence, the detailed structure of the CMBBZ in this region provides further evidence in support of the rift zone model. </p> / Thesis / Master of Science (MSc)
166

A High Level Synthesis Approach for Reduced Interconnects and Fault Tolerance

Lemstra, David 01 1900 (has links)
<p> High Level Synthesis (HLS) is a promising approach to managing design complexity at a more abstract level as integrated circuit technology edges deeper into sub-micron design. One useful facet of HLS is the ability to automatically integrate architectural components that can address potential reliability issues, which may be on the increase due to miniaturization. Research into harnessing HLS for fault tolerance (FT) has been progressing since the early 1990's. There currently exists a large body of work regarding methods to incorporate capabilities such as fault detection, compensation, and recovery into HLS design.</p> <p> While many avenues of FT have been explored in the HLS environment, very little work has considered the effectiveness and feasibility of these techniques in the context of large HLS systems, which presumably is the raison d'etre of HLS. While existing HLS FT approaches are often elegant and involve highly sophisticated techniques to achieve optimal solutions, the costs of HLS infrastructure in regards to scalability are not well reported. The intent of this thesis is to explore the ramifications of applying common HLS techniques to large designs.</p> <p> Furthermore, a new HLS tool entitled RIFT is presented that is specifically designed to mitigate infrastructure costs that mount as greater parallelism is utilized. RIFT is named for its design philosophy of "Reducing Interconnects for Fault Tolerance". RIFT iteratively builds a logical hardware representation, which consists of both the components instantiated and their interconnections, one operation at a time. It chooses the next operation to be "mapped" to the burgeoning design based on scheduling constraints as well as the extra hardware and interconnect costs required to support a particular selection. Emphasis is placed on minimizing the delay of the datapath in effort to reduce the performance cost associated with the extra interconnects needed for FT. RIFT has been used to generate efficient solutions for FT designs requiring as many as a thousand operations.</p> / Thesis / Master of Applied Science (MASc)
167

Virtuella möten i skogen : Ett verktyg för att underlätta Gällö skogs möten i skogen genom 3D-konferens

Sandström, Anton January 2018 (has links)
Within Gällö skog there is an increasing need for meetings in the forest at a distance. This is because many landowners do not live at or close to their forest property. The aim of this work was therefore to find a 3D conference solution for Gällö skog. The work has been carried out using the design process and Pugh's relative decision matrix. First, a requirement specification was made for both hardware and software selection. Then the Facebook Spaces, Rumii and AltSpaceVR software were investigated against this. When none of the aforementioned software was sufficiently satisfactory for this work, it was decided to develop a software. The developed software is based on a website and was developed by modifying an existing project from github.com. Through the modification made in the project, all requirements in the specification could ultimately be achieved. However, with some restrictions. The software works best in the Mozilla Firefox browser, and is not compatible with the iPhone. The user friendliness of Gällö skog also has development potential. The hardware in this work was chosen by comparing the VR glasses HTC Vive and Oculus Rift against each other and the developed requirement specification. As a result, HTC Vive was bought for the project. This because it fulfilled most of the work requirements, and that it had other features that enabled the headset to be used in future work. Finally, The conclusion of this work was that until this technology has come further, this solution may be insufficient. The idea is good, the solution is good, but the technology needs to come further for fully satisfactory results. When the VR technololgy have advanced further, a solution like this could be something that could be useful to companies. This because the inertaction of a 3D conference is improved compared to today's video chat. / Inom Gällö skog finns ett ökande behov av att hålla möten i skogen på distans. Detta eftersom många markägare inte bor på, eller vid sin skogsfastighet. Målet med detta arbete var därför att hitta en 3D-konferenslösning åt Gällö skog. Arbetet har genomförts med hjälp av designprocessen samt Pughs relativa beslutsmatris. Först togs en kravspecifikation fram både för val av hårdvara och mjukvara. Efter det undersöktes mjukvarorna Facebook Spaces, Rumii och AltSpaceVR mot denna. När ingen av de nämnda mjukvarorna var tillräckligt tillfredsställande för detta arbete så valdes att ta fram en egen mjukvara. Den framtagna mjukvaran baseras på en webbplats och togs fram genom att modifiera ett befintligt projekt från github.com. Genom den modifikation som gjordes i projektet så kunde alla krav i kravspecifikationen till slut uppnås. Dock med vissa restriktioner. Mjukvaran fungerar bäst i webbläsaren Mozilla Firefox, och är ej kompatibel med Iphone. Även användarvänligheten för Gällö skog har utvecklingspotential. Hårdvaran i detta arbete togs fram genom att jämföra VR-glasögonen HTC Vive och Oculus Rift mot varandra och den framtagna kravspecifikationen. Resultatet av detta blev att HTC Vive köptes in till projektet. Detta för att de uppfyllde flest av arbetets krav, samt att de hade övriga funktioner som gjorde att de kan användas även i framtida arbeten. Slutsatsen av detta arbete blev till slut att tills dess att tekniken kring detta har hunnit längre så blir denna lösning möjligtvis otillräcklig. Tanken är god, lösningen bra, men tekniken behöver komma längre för fullt tillfredsställande resultat. När VR-tekniken kommit längre skulle en lösning likt denna kunna vara något som kan bli användbart för fler företag. Detta eftersom interaktionen i en 3D-konferens förbättras jämfört med dagens videochattar.
168

Age, récurrence et mécanismes de déstabilisation des flancs des volcans océaniques d'après l'exemple de Tenerife (iles Canaries) / Age, recurrence and triggering mechanisms of flank collapse episodes on ocean islands after the Tenerife Island exemple (Canary Islands)

Boulesteix, Thomas 30 September 2011 (has links)
La croissance des volcans océaniques est fréquemment ponctuée par des effondrements latéraux géants qui peuvent générer des avalanches de débris volumineuses et engendrer des tsunamis dévastateurs. Néanmoins, les causes, les mécanismes et les conséquences de telles déstabilisations, critiques pour la caractérisation des aléas, demeurent largement incompris.L'île de Tenerife (Canaries, Espagne) constitue une cible privilégiée pour étudier ces phénomènes. Son évolution récente inclue le développement d'un volcan central différencié et d'une ride volcanique proéminente le long d'une rift-zone principale NE-SW (NERZ). Durant le dernier Myr, ces systèmes ont été tronqués par trois effondrements de flanc géants, dont la semelle est partiellement accessible à la faveur de galeries souterraines à usage hydrogéologique.Cette thèse développe une analyse systématique des relations entre construction volcanique et instabilités récurrentes le long de l’axe de la NERZ. L'approche inclut des investigations de terrain en surface et dans les galeries, afin de reconnaître et d’échantillonner les séquences volcaniques affectées par chaque effondrement et remplissant leurs structures; la datation K/Ar Cassignol-Gillot sur phases séparées pour en contraindre l’âge précisément ; des reconstructions morphologiques 3D afin d'estimer le volume des édifices et des structures gravitaires; des analyses chimiques sur roches totales, visant à caractériser l’évolution de la composition des laves avant et après chaque déstabilisation.Les nouveaux résultats montrent le fonctionnement intermittent des différents tronçons la NERZ, avec un schéma récurrent comprenant :1) la croissance rapide d'un édifice imposant, dont la charge induit la création de niveaux de stockage superficiels et l’éruption de termes différenciés visqueux, favorisant l'inflation locale de la structure et sa déstabilisation2) la rupture proprement dite, datée à environ 840 ka, 525 ka et 175 ka (glissements de Güimar, La Orotava et Icod, respectivement)3) une réponse éruptive immédiate, impliquant la vidange rapide (<50kyr) du système d’alimentation, et le comblement des loupes de glissement sous des dizaines de km3 de lave.4) Un déplacement consécutif de la construction volcanique vers les secteurs moins matures de la NERZ (moindre épaisseur de l'édifice/moindre pression lithostatique)Nous montrons que les phénomènes de charge/décharge ont une influence primordiale sur le développement des instabilités gravitaires et l'évolution des systèmes d'alimentation des îles océaniques. / The growth of oceanic volcanoes is frequently punctuated by large flank collapses, which can generate voluminous debris avalanches and destructive tsunamis. The causes, the mechanisms and the consequences of such instabilities, crucial for risk assessment, remain poorly understood.Tenerife (Canary Islands, Spain) is a target of particular interest to study such phenomena. Its recent evolution includes the development of a large silicic central volcano and a prominent volcanic ridge along a main NE-SW trending rift zone (NERZ). During the last Myr, these volcanic systems have been truncated by three large flank collapses, the base of which is partly accessible through underground water mining galleries.This thesis develops a systematic analysis of the relationships between volcanic construction and recurrent flank instabilities along the NERZ. Our approach includes field investigations at the surface and in the galleries to identify and sample the volcanic units affected by each landslide and the successions filling their scar; unspiked K/Ar dating (Cassignol-Gillot technique) on fresh separated groundmass to constrain precisely the timing of the landslides; 3-D morphological reconstructions to estimate the volume of the edifices and landslides structures; and whole-rock geochemical analyses to characterize the compositional evolution of the magma prior to and after each collapse event.Our new results show the intermittent functioning of the various sections of the NERZ with a recurrent pattern comprising:(1) The rapid construction of a large volcanic edifice. The resulting load favors the creation of superficial storage levels, the associated evolution of the magma and the eruption of viscous differentiated terms, favoring local inflation of the structure and its destabilization(2) The collapse of a flank of the NERZ, dated at ca. 840 ka, 525 ka, and 175 ka (Güimar, La Orotava and Icod, events respectively)(3) An immediate eruptive response, implying the rapid emptying (<50kyr) of the feeding system and the filling of the landslide scars under tens of km3 of lava.(4) The subsequent displacement of volcanic activity towards the less mature sectors (lower thickness/lower lithostatic pressure).We show here that loading/unloading processes have a strong influence on the development of gravitational instabilities and the evolution of the magma feeding systems on such large intraplate volcanic islands.
169

Estudo da conexão entre as drenagens do Médio Paraíba do Sul e do Alto Tietê: o caso do cotovelo de Guararema - SP, Brasil / Study of the connection between the drainages of the rivers Tietê and Paraíba do Sul: the case of Guararemas elbow - SP, Brazil

Pasa, Vaniza 12 August 2013 (has links)
Este trabalho trata da caracterização regional entre as drenagens dos rios Paraíba do Sul e Tietê, associada ao processo de captura fluvial, situado entre os municípios de Guararema e Mogi das Cruzes, no Estado de São Paulo. Parte-se da hipótese de processo de captura fluvial no médio curso do Paraíba do Sul e formação do cotovelo de Guararema, o que caracteriza essa anomalia como uma das mais interessantes do planeta Terra. É comum na região o padrão dendrítico e adensamento de drenagens cortados por falhas e fraturas de diversas idades. O embasamento é composto de estruturas cristalinas recobertas por pacotes sedimentares do Terciário e Quaternário. No Graben do Paraíba, superfície alongada e rebaixada entre as Serras do Mar e Mantiqueira, a forte declividade favorece o processo erosivo. A área caracterizada por esses dois importantes rios do território brasileiro é parte integrante do Sistema de Bacias Tafrogênicas do Rift Continental do Sudeste do Brasil (RCSB), a qual foi afetada por falhas NE-SW de grande expressão regional, e o processo de captura seria o responsável pela atual configuração da rede de drenagem. A reativação e movimento de blocos regionais dos períodos Mesozóico e Cenozóico inverteu a direção do Rio Paraíba do Sul em seu setor central, que no passado tributava suas águas no Rio Tietê. Como consequência desse reajustamento regional, alguns dos seus tributários teriam rompido os divisores de água que o separavam das cabeceiras do Tietê e capturado parte de suas drenagens através de processo de recuo de regressivo. O que comprova a captura é a localização do vale seco, feição que pode indicar a antiga ligação entre os dois rios, que foi identificada na área desta pesquisa por meio de análise de cartas, mapas, perfis e fotointerpretação. Devido ao elevado poder erosivo no setor do médio vale do Rio Paraíba, novas capturas podem estar em processo de evolução. / This work deals with the characterization regional drainages between the rivers Tietê and Paraíba do Sul, associated with the capture process river, located between the cities of Guararema and Mogi das Cruzes, State of São Paulo. It starts with the hypothesis capture process in middle course of river Paraíba do Sul and training elbow Guararema what characterizes this anomaly as one of the most interesting of the planet Earth. It is common in the region and the dendritic pattern of drainage densification cut by faults and fractures of various ages. The basement consists of crystalline structures covered by sedimentary packages Tertiary and Quaternary. The Graben Paraíba, elongated surface and lowered between the Serra do Mar and Mantiqueira, the strong declivity favors the erosion process. The area is characterized by these two important rivers of the Brazilian territory is part of the Watershed System Tafrogênicas Continental Rift of Southeastern Brazil (RCSB), which was affected by NE-SW faults of great regional expression, and the capture process would be responsible for the present configuration of the drainage network. The reactivation and movement of regional blocks of Mesozoic and Cenozoic periods inverted the direction of the Paraíba do Sul River in its central section, which in the past taxed waters in Rio Tietê. As a result of this regional readjustment, some of its tributaries have broken the watershed that separated him the headwaters of the Tietê and captured part of its drainage through the process of regressive retreat. This proves the catch is the location of the valley dry feature that may indicate the ancient link between the two rivers, which was identified in this research area through the analysis of charts, maps, profiles and photo interpretation. Due to the high erosive power sector in the middle valley of the River Paraíba, new catch may be in the process of evolution.
170

Sismicité, couplages sismique-asismiques et processus transitoires de déformation dans un système de failles actives : le rift de Corinthe, Grèce / Seismicity, seismic-aseismic couplings and transient deformation processes in an active fault system : the Corinth rift, Greece

Duverger, Clara 29 November 2017 (has links)
La partie ouest du rift de Corinthe, en Grèce, s'ouvre à une vitesse d'environ 15 mm par an générant un taux de déformation parmi les plus élevés au monde, quelques séismes destructeurs de magnitude M>6 par décennie, et une forte activité microsismique irrégulière spatialement et temporellement. Afin de mieux comprendre les mécanismes liés à cette déformation crustale et de préciser les structures majeures actives, ce travail de recherche exploite la base de données sismologiques du Corinth Rift Laboratory de 2000 à 2015 en analysant finement les microséismes et leur évolution spatio-temporelle. La relocalisation globale des sources sismiques ainsi que leur classification en multiplets ont permis de préciser la géométrie des failles et d'identifier des comportements mécaniques différents. La zone ouest, au milieu du golfe, est affectée par des variations de pressions de fluides dans une couche géologique, entraînant des migrations des essaims de microséismes à des vitesses d'environ 50 m par jour. Les multiplets profonds de la partie centrale, près de la côte nord, sont persistants et semblent déclenchés par des épisodes de glissements lents asismiques sur un détachement immature pouvant atteindre la croûte ductile. Le faible pourcentage de déclenchement dynamique par les ondes sismiques suggère que l'état global du système de failles n'est pas au seuil critique de rupture. La magnitude des séismes est corrélée à l'impulsivité initiale de la rupture. Ces résultats précisent la dynamique de déformation du rift, les interactions sismique-asismiques, et permettront d'améliorer les modèles d'aléas sismiques de la région / The western part of the Corinth Rift in Greece is opening at about 15 mm per year, generating one of the highest deformation rates in the world, some destructive earthquakes of magnitude M>6 per decade, and high microseismic activity irregular in space and time. In order to better understand the mechanisms related to this crustal deformation and to specify the major active structures, this research work makes use of the seismological database of the Corinth Rift Laboratory from 2000 to 2015 by finely analyzing microearthquakes and their spatio-temporal evolution. The global relocation of the seismic sources and their classification into multiplets enable to refine the geometry of the faults and to identify different mechanical behaviors. The western zone, in the middle of the gulf, is affected by fluctuations of fluid pore pressures in a geological layer, resulting in microseismic swarm migrations at a velocity of about 50 m per day. The deep multiplets of the central part, near the northern coast, are persistent and appear to be triggered by episodes of slow aseismic slip along an immature detachment, which can reach the ductile crust. The low percentage of dynamic triggering by passing seismic waves suggests that the overall state of the fault system is not at the critical breaking point. The magnitude of earthquakes is correlated with the initial impulsiveness of the rupture. These results specify the dynamics of the rift deformation, the seismic-aseismic interactions, and will make possible the improvement of the seismic hazard models of the region

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