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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.
151

Les pseudonymes dans les littératures yiddish et hébraïque du milieu du XIXe siècle au milieu du XXe siècle / Pseudonyms in Yiddish and Hebrew Literatures, from the Mid-19th Century to the Middle of the 20th Century

Bar-Kochva, Sharon 06 February 2015 (has links)
Les littératures yiddish et hébraïque modernes sont étroitement liées par une histoire commune et partagent également de multiples traits stylistiques et thématiques. Or, une différence importante peut être remarquée quant à l’usage des pseudonymes dans les deux langues. Dans la littérature yiddish moderne, la pseudonymie est très importante, aussi bien du point de vue quantitatif que qualitatif, et une grande partie des plus importants auteurs yiddish sont connus principalement sous leur pseudonyme, alors que dans la littérature hébraïque moderne les noms de plume restent un phénomène relativement marginal. La présente recherche analyse la pseudonymie dans les deux littératures, dans le but d’expliquer cet écart. Nous commençons par une analyse des modes de construction des pseudonymes pour en constituer une typologie générale. Par la suite, nous nous concentrons sur les pseudonymes « durables », c'est-à-dire ceux qui accompagnent les auteurs sur le long terme et façonnent leur image publique, pour décrire en détail dans quelles circonstances et de quelles manières ils sont utilisés. Enfin, nous utilisons les informations recueillies pour démontrer que la pseudonymie est un phénomène social, et pour isoler les facteurs sociaux et historiques qui ont conduit à l’adoption de la pseudonymie comme l’une des « traditions inventées » de la littérature yiddish moderne. / Modern Yiddish and Hebrew literatures are closely connected by a common long history, sharing many stylistic and thematic features. However, both literatures significantly differ in their use of pseudonyms. In Yiddish literature, authors’ pseudonyms appear rather frequently, and a significant number of the most important writers are known mainly in their pseudonyms, while in modern Hebrew literature pen names remained a relatively marginal occurrence. This research analyses pseudonymity in both literatures in order to explain this discrepancy. In the first chapter, the various patterns used in building pseudonyms are analysed, so to establish a general typology of the phenomenon. Subsequently, I focus on the "lasting" pseudonyms, namely those that accompany authors for a long time, shaping and determining their public image. In the second chapter I describe in detail under which circumstances and in what ways the "lasting" pseudonyms were created and used. Finally, in the last part the information analysed previously is utilised, clarifying that pseudonymity is actually a social phenomenon, and defining the social and historical factors that led to the adoption of pseudonymity as one of the "invented traditions" of modern Yiddish literature.
152

Caracterização espaço-temporal de plumas de sedimentos por sensoriamento remoto: um estudo de caso na foz do rio Paraíba do Sul. / Space-Time characterization of sediments plumes for remote sensoring: a case study in the Foz do Rio Paraíba do Sul.

Kelly Ferreira Esch 29 January 2010 (has links)
Sedimentos em suspensão representam um dos principais fatores que afetam a qualidade dos sistemas aquáticos no mundo; influenciam os processos geomórficos de construção da paisagem e podem indicar problemas de erosão e perda de solo na bacia hidrográfica contribuinte. O seu monitoramento espacial e temporal é fundamental nas atividades de gestão ambiental de áreas costeiras. Nesse sentido, a hipótese básica desta pesquisa é que o padrão espacial e temporal de plumas de sedimentos costeiras associado ao regime hidrológico do rio pode ser caracterizado a partir de imagens orbitais de média resolução espacial. Para comprová-la, elegeu-se a foz do rio Paraíba do Sul como área de estudo para definição e teste metodológico, e formulou-se como principal objetivo mapear qualitativamente a pluma costeira deste rio a partir de imagens Landsat 5 e CBERS-2, ao longo do período compreendido entre 1985 e 2007. As datas avaliadas foram criteriosamente definidas através de três estratégias de análise, totalizando cinqüenta imagens. Pesquisa bibliográfica e avaliação da resposta espectral da feição de interesse nas imagens selecionadas consistiram nas etapas principais da definição da metodologia. As plumas foram então identificadas, mapeadas e extraídas; posteriormente, suas características espaciais e temporais foram analisadas por intermédio de sistemas de informação geográfica e avaliadas em conjunto com dados históricos de vazão. Os resultados indicam que a banda do vermelho forneceu uma melhor discriminação interna da pluma, sendo, portanto, utilizada como base para as análises realizadas neste trabalho. Com exceção do procedimento de correção atmosférica, a metodologia proposta consiste na utilização de técnicas simples de processamento digital de imagens, baseadas na integração de técnicas semi-automáticas e de análise visual. A avaliação do padrão dos sedimentos e dos mapas temáticos qualitativos de concentração de sedimentos em suspensão indica a forte diferenciação existente entre cenários representativos de épocas de cheia e seca do rio. Análises espaciais do comportamento da pluma contribuem ainda para um maior conhecimento do espaço geográfico, fornecendo subsídios aos mais variados setores do planejamento e gestão ambiental. / Suspended sediments are a major factor affecting water quality in aquatic ecosystems of the world; they do influence the geomorphological processes of environmental formation and may indicate erosion problems and loss of ground on the contributing watershed. Its spatial and temporal monitoring is fundamental in the activities of the environmental management of the coastal areas. In that direction, the basic hypothesis of this research is that the spatial and temporal pattern of coastal plumes of sediments associated to the hydrological regime of the river may be characterized from orbital images of medium spatial resolution. To prove this, it was elected the mouth of Paraiba do Sul river as study area for defining and testing the methodology, which was formulated as principal purpose to map qualitatively the coastal plumes of this river from the images of Landsat 5 and CBERS-2, from the period between 1985 and 2007. The evaluated dates were defined with criteria through three strategies of analysis, totaling fifty images. Literature review and evaluation of the spectral response of the feature of interest consisted on the main steps of the definition of the methodology. The plumes were so identified, mapped and extracted; afterward, its spatial and temporal characteristics were analyzed by geographical information systems and evaluated together with historical data of river discharge. The results indicate that the red band yielded a better internal discrimination of the plume, being, therefore, used as basis to the analyses realized on this work. With exception of the procedure of atmospheric correction, the methodology proposal consists on the utilization of simple techniques of digital processing of images, based on the integration of semi-automatic and visual analyses techniques. The evaluation of the sediments pattern and qualitative thematic maps of suspended particulate matter indicates the strong differentiation existing between scenarios representing the periods of high and low waters of the river. Spatial analyses of the behavior of the plumes even contribute to a better knowledge of the geographical space, supplying subsidies to the most assorted sectors of environmental planning and management.
153

Suíte de xenólitos de Cerro de los Chenques (Argentina) evolução dos processos de metassomatismo durante a diferenciação do manto litosférico

Rieck Junior, Norberto January 2008 (has links)
A suíte de xenólitos ultramáficos do Cerro de los Chenques, Patagônia (44°52’19”S/70°03’57”W), represeta o Manto Litosférico Continental nesta região. Estas rochas guardam registros dos processos a que o manto esteve sujeito durante todo o período de evolução e diferenciação do próprio manto litosférico e de formação de crosta continental. Utilizando-se dados de petrologia, de geoquímica mineral e rocha total de elementos maiores e menores e dados isotópicos, é possível demonstrar que os xenólitos do Cerro de los Chenques possuem paragênese mineralógica primária formada por olivina, enstatita, diopsído e espinélio e que esta paragênese está em equilíbrio, como pode ser observado nos dados de química mineral. Desta forma estas rochas são classificadas como espinélio lherzolitos, espinélio harzburgitos e espinélio olivinawebsteritos, com temperatura e pressão de equilíbrio variando de 782°C a 1029ºC e 14kbar a 19 kbar. Mesmo que a paragênese primária esteja em equilíbrio, ocorrem instabilidades locais com formação de fusão na forma de bolsões de vidro silicáticos e de uma paragênese secundária composta por olivina, diopsídio e espinélio. Os dados geoquímicos de rocha total mostram depleção nos elementos alcalinos e nos elementos traço em relação ao manto primitivo, ilustrando que houve processo de fusão parcial atuando nestas rochas. As amostras estudadas apresentam também feições características de processos de metassomatismo em momentos distintos e guardando características particulares em cada um deles. O primeiro evento metassomático foi determinado como sendo originado por uma pluma de ascenção astenosférica, sendo denotado principalmente pelo enriquecimento nos HFSE (Nb e Ta) e alguns elementos incompatíveis LILE. Este evento é responsável pela metassomatização dos lherzolitos e harzburgitos e pela formação dos olivina-websteritos a partir de um manto granadalherzolítico, onde a granada se torna instável para a formação de clinopiroxênio e espinélio. Eventos metassomáticos posteriores a este também foram identificados, sendo desta vez relacionados a líquidos provenientes da desidratação e fusão de placas oceânicas em zonas de subducção. Um desses eventos está relacionado a colagem dos micro-continentes Maciço Norte Patagônico e Maciço del Deseado, por volta de 350 Ma caracterizado principalmente pelo enriquecimento nos ETR leves em relação aos pesados. O outro, mais recente, relacionado à subducção da Placa Oceânica de Nazca, onde o principal evento é o enriquecimento nos elementos calcófilos (Pb, Sn, W e Sb), que também está registrado em todas as suítes de xenólitos da Patagônia. Foi determinado ainda, que os basaltos de platô de back-arc, resposnsáveis por trazer os xenólitos à superfície não infiltram nos xenólitos, a ponto de alterar a química de suas rochas. / The ultramafic xenolith set from Cerro de los Chenques, Patagônia (44°52’19”S/70°03’57”W), represents the Sub Continetal Lithospheric Mantle (SCLM) of this region. All rocks record processes in the mantle that happened during all period of lithospheric mantle differentiation and crust formation. Using the petrologica data, mineralochemistry, and major, trace and isotope element geochemistry, it is possible to demonstrate that the xenoltihs equilibria mineral assemblage is olivine, enstatite, diopside and spinel. These rocks are classified as spinel lherzolites, spinel harzburgite and spinel olivine websterite, with temperature and pressure equilibrium of 782° to 1029°C and 14 19 kbar, respectively. It is also possible to point out that metassomatic process occurred in the xenolith rocks, which resulted in the crystallization of a secondary assemblage formed by olivine, diopside and spinel, and the formation of silicate melt pockets around spinel and clinopyroxene. Geochemistry data show alkalis and trace elements depletion in relation to primitive mantle as a result of the melting events. The studied samples also show metasomatic events in different periods, with different characteristics. The first metasomatic event was related to an upwelling of an asthenospheric plume, responsible for the HFSE (Nb and Ta) and some incompatible elements (LILE) enrichment in all lithologies, and by the formation of the olivinewebsterite from a garnet-lherzolite, in which garnet reacts out to form clinopyroxene and spinel. Two others metasomatic events must have happened, following this one, both related to fluids and melts originated from the dehydration and melting of the subducting slab. One of these events is related to the collage of the Norte-Patagônia massif to del Deseado massif micro-continets, around 350 Ma, which resulted in the light REE enrichment. The other one, more recent, is related to the Nazca subducting slab, responsible for the enrichment in chalcophile elements (Pb, Sn, W and Sb), which is also observed in all mantle xenoliths from Patagonia. We also discard any infiltration of the host-basalt as the responsible for the ultramafic xenoliths chemical modification.
154

Analytical Models for Plume Length Estimations

Yadav, Prabhas Kumar 13 July 2012 (has links)
This thesis dealt with the techniques that could be used for the pre-assessment of contaminated sites. The goals of the thesis were based on a simple fact that every contaminated site possesses certain potential to degrade natural resources, specifically groundwater and land resources. The thesis focused on using mathematical and statistical techniques to predict the maximum length of contaminated plumes or Lmax, which it considered as a key parameter that could be used for the site assessment. As the first thesis work, data from KORA sites were compiled and analysed. From the analyses, it was found that the Lmax for BTEX plumes are in average under 150 m long. Further, for this work, Analytical Models that can be used to estimate Lmax were reviewed and, examples comparing model and fifield Lmax were presented. The second work for the thesis focused on a development and analysis of a new 3D-analytical model for a fifinite planar and fully penetrating source. An implicit expression for predicting Lmax was obtained. The analysis of the developed model suggested that the longest Lmax will result if the source takes an approximately square shape. The last part of the thesis improved the 3D-analytical model obtained in the second work by presenting an expression for a fifinite planar source that only partially penetrates the aquifer. For this work, a very simple numerical technique was developed that not only simplififies numerical analysis of the scenarios considered in this thesis but it also bears potentials to be used for very complex subsurface reaction transport scenarios. This thesis has been successful in narrowing research-gaps on problems related to contaminated sites management. / Diese Doktorarbeit befasste sich mit Methoden, welche für eine Vorabbewertung von kontaminierten Standorten genutzt werden können. Die Ziele der Arbeit basierten auf dem einfachen Fakt, dass jeder kontaminierte Standort ein bestimmtes Potential besitzt, natürliche Ressourcen, speziell Grundwasser- und Bodenressourcen, in ihrer Qualität negativ zu beeinträchtigen. Die Arbeit war auf die Nutzung mathematischer und statistischer Techniken zur Abschätzung der maximalen Schadstofffahnenlänge, auch Lmax, fokussiert, welche als entscheidender Parameter für die Standortbewertung genutzt werden kann. Der erste Teil der Doktorarbeit beinhaltete die Zusammenstellung und Analyse von Daten einer Vielzahl von KORA-Standorten. Anhand dieser Untersuchungen konnte festgestellt werden, dass Lmax von BTEX-Fahnen im Mittel unterhalb von 150 m liegt. Des Weiteren wurden für diese Arbeit analytische Modelle, welche für die Abschätzung von Lmax genutzt werden können, kritisch bewertet und vergleichende Beispiele zwischen mit Modellierung bestimmter und im Feld ermittelter Lmax präsentiert. Der zweite Teil der Doktorarbeit zielte auf die Entwicklung und Analyse eines neuen dreidimensionalen, analytischen Models für eine finite, planare und über die komplette Mächtigkeit vorherrschende Quelle ab. Es konnte ein impliziter mathematischer Ausdruck zur Vorhersage von Lmax gewonnen werden. Die Analyse des Models wies darauf hin, dass maximale Lmax erreicht werden, wenn die Quelle eine annähernd quadratische Form aufweist. Der letzte Teil der Doktorarbeit diente der Weiterentwicklung des dreidimensionalen, analytischen Modells aus dem zweiten Teil durch die Entwicklung eines Ausdrucks für eine finite, planare Quelle, welche jedoch nur teilweise die Mächtigkeit des Grundwasserleiters kontaminiert. Für diese Arbeit wurde ein sehr einfacher numerischer Ansatz entwickelt, welcher die numerische Analyse der in dieser Arbeit berücksichtigten Szenarien nicht einfach nur erleichtert, sondern auch das Potential beinhaltet diesen auf komplexe, reaktive Transportszenarien im Untergrund anzuwenden. Abschließend kann gesagt werden, dass diese Arbeit erfolgreich zur Verringerung von Forschungslücken in der Problematik des Managements kontaminierter Standorte beigetragen hat.
155

Comparison of CO2 and DIC concentrations in bays with and without river discharge in an ice-covered lake

Rosendahl, Anna January 2020 (has links)
Many of the world’s lakes are located at high latitudes in the northern hemisphere where seasonal ice cover is common. The ice restricts lake-atmosphere gas exchange, causing an under-ice accumulation of CO2. However, there are few spatial under-ice CO2 studies of river influence on lakes. Here, I examine the river plume of a river-influenced bay and compare it to a control bay without river influence in lake Örträsk, a humic of 7 km2 lake in boreal Sweden. There was no relationship between CO2 or DIC and distance from the Vargån river outlet in Vargån bay, even though the CO2 and DIC concentration of the river was found lower in Vargån river (median CO2: 53,2 µM; DIC: 178 µM) than in Vargån bay (median CO2: 84,7 µM; DIC: 301 µM). The median values of the control bay were CO2: 92,7 µM and DIC: 345 µM. There was a negative relationship in CO2 concentration with distance in the control bay, but not in DIC. The control bay had a higher concentration of CO2 at 0-60 m distance than Vargån bay, but there was no difference at 70-180 m. The DIC concentration was higher in the control bay than in Vargån bay. I have reported lower CO2 and DIC concentrations in the river than in the lake, which is not in accordance with literature and is probably due to an earlier ice-melt in the river than in the lake. The negative CO2 relationship in the control bay is likely due to sediment respiration.
156

Analysis of Efficiency of Laser Ablation of Aluminum By Modeling of Plume Shielding Effect

Hanich, Maxwell James 25 August 2020 (has links)
No description available.
157

Methane Plume Detection Using Passive Hyper-Spectral Remote Sensing

Barnhouse, Willard D., Jr. 03 November 2005 (has links)
No description available.
158

The Ecotoxicological Impacts of Copper in Aquatic Systems

Lahman, Sara Elisabeth 27 March 2015 (has links)
No description available.
159

Using Plasmas for High-Speed Flow Control and Combustion Control

Keshav, Saurabh 01 October 2008 (has links)
No description available.
160

Fundamental Chemical Kinetic Experiments of Combustion Products inside a Shock Tube

Pothen, Alex-Abraham 01 January 2024 (has links) (PDF)
The use of lateral divert thrusters on hypersonic vehicles would allow for fine-tuned attitude control at high Mach numbers. However, the jet interaction effects of lateral thrusters on the hypersonic flow field have not been investigated thoroughly. Computational Fluid Dynamics (CFD) can provide preliminary modeling of the jet interaction, but several variables such as vehicle geometry, velocity, and altitude, result in computationally expensive modeling or loss in accuracy of the results. Therefore, the goal of chemical kinetics testing and chemical model verification is to enhance the fidelity of the jet interaction effects, specifically the plume reaction with air and the plume interaction with vehicle instrumentation.

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