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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.
521

Texture analysis of high resolution panchromatic imagery for terrain classification

Humphrey, Matthew Donald 06 1900 (has links)
Approved for public release, distribution is unlimited / Terrain classification is studied here using the tool of texture analysis of high-spatial resolution panchromatic imagery. This study analyzes the impact and effectiveness of texture analysis on terrain classification within the Elkhorn Slough Estuary and surrounding farmlands within the central California coastal region. Ikonos panchromatic (1 meter) and multispectral (4 meter) imagery data are examined to determine the impact of adding texture analysis to the standard MSI classification approaches. Spectral Angle Mapper and Maximum Likelihood classifiers are used. Overall accuracy rates increased with the addition of the texture processing. The classification accuracy rate rose from 81.0% for the MSI data to 83.9% when the additional texture measures were added. Modest accuracy (55%) was obtained from texture analysis alone. The addition of textural data also enhanced the classifier's ability to discriminate between several different woodland classes contained within the image. / Lieutenant Commander, United States Navy
522

The Usefulness of Ground Penetrating Radar in locating burials in Charity Hospital Cemetery, New Orleans

Mitchell, Monique Tashell 16 May 2008 (has links)
The Charity Hospital Cemetery in New Orleans, Louisiana, was used as a potter's field for over 150 years. When Charity Hospital considered selling a portion of the property ground penetrating radar (GPR) and thermal infrared (TIR) data were collected in the cemetery to locate unmarked graves. The TIR data could not be used because the expert died before compiling the TIR data. Therefore, the GPR data was the sole source of subsurface information. GPR anomalies were used to excavate 3 areas where bones and hospital supplies were subsequently found, unfortunately very limited analyses were possible on the analog GPR data. The study presented here involved digitizing data and conducting a more thorough analysis of map patterns to determine whether GPR data could be used reliably to locate burials in the cemetery. The study's result indicates that GPR is a reliable source for burial detection and other anomalies in the subsurface.
523

Régulation du cycle vésiculaire et de l’approvisionnement en GABA des interneurones de l’hippocampe en fonction de l’activité / Regulation of GABA supply and vesicular cycle in function of activity of hippocampal interneurons

Bonet, Laurine 30 September 2016 (has links)
Les interneurones GABAergiques dans l’hippocampe forment de petites populations diverses de neurones inhibiteurs contrôlant le transfert d’informations dans de larges ensembles de cellules principales. Ils compensent leur infériorité numérique par de vastes arborisations axonales capables de maintenir une libération vésiculaire de GABA à haute fréquence, et d’ajuster précisément la balance entre excitation et inhibition pour différents régimes d’activité du réseau. Les petites synapses centrales contiennent un nombre limité de vésicules synaptiques dont le recyclage par endocytose est essentiel au maintien de la transmission pendant une activité répétée. Le remplissage en GABA de ces vésicules recyclées est dépendant d’un approvisionnement des terminaisons en GABA suffisant pour faire face à la demande de recyclage créée par l’activité. Nos résultats mettent en évidence de nouveaux mécanismes d’adaptation de l’approvisionnement aux besoins imposés par le recyclage vésiculaire selon le régime d’activité, ainsi qu’un couplage direct entre le cycle de neurotransmetteurs et le cycle vésiculaire. Nous montrons que les transporteurs de glutamine sont responsables d’une potentialisation de l’approvisionnement des varicosités en GABA lors d’une activité répétée, probablement par une augmentation du nombre de ces transporteurs à la membrane. En développant et en utilisant des paradigmes expérimentaux nouveaux, nous montrons que la régulation métabolique du cycle vésiculaire passe par une adaptation du pool de vésicules recyclantes à la disponibilité en neurotransmetteurs. La nature du senseur de cette régulation et sa localisation cytosolique ou luminale restent à déterminer / In the hippocampus, GABAergic interneurons represent only 10% of the neuronal population but are able to synchronize the activity of large neuronal networks. They compensate their numerical inferiority by a large axonal arborization to sustain synaptic activity at high frequency and adjust the balance between excitation and inhibition for different regime of activity. Since small central synapses contain a limited pool of vesicles, their recycling by endocytosis is essential to maintain transmission during repeated activity. The filling of recycling vesicles with GABA is dependent on its supply in terminals which should be adjusted to the demand imposed by vesicular recycling. Our results reveal new transporter mechanisms that adapt GABA supply to neuron activity, suggesting a direct coupling between the neurotransmitter and the vesicle cycles. We show that high recycling activity increases GABA supply, probably by increasing the number of glutamine transporters at the membrane. By developing and using FM5-95 and VGAT-pHluorin with a new experimental paradigm, we provide evidence for a metabolic regulation of the vesicle cycle that involves a dynamic adaptation of the recycling pool to the neurotransmitter availability. The nature of the sensor of this regulation and its cytosolic or luminal location remain to be determined.
524

A theoretical interdisciplinary analysis for a new cognitive and emotional neuroscience of appreciation and artistic creation

Romp, Andreas Johannes 01 1900 (has links)
Text in English / This work is organised around two main objectives: a) the formulation of a new conceptual framework as the basis for a new scientific aesthetic; and (b) an attempt to explain the possibilities and current limitations of neuroscience in aesthetics. The first part of the work is devoted to the conceptual foundations of aesthetics. In the first chapter, I analyse the philosophical assumptions reflected in neuroaesthetics. In particular, I would like to show that the concept of art on which neuroaesthetics is based is both conceptually and empirically untenable. In the second chapter, I propose a new conceptual framework for a theory of aesthetics; in particular, I present new definitions of key concepts in aesthetics, such as 'art', 'artistic system', 'artistic movement', 'artwork', and so forth. Furthermore, in the second chapter, I advance the view that—even though the neurosciences are an essential part of aesthetics—not every aesthetic problem requires a neuroscientific solution. In other words, there are aesthetic problems that cannot be answered satisfactorily by neuroscience using only its special concepts and terminology. Some questions may require additional sociological, physical and/or semiotic concepts, and explanatory devices. The second part of this thesis deals with the experimental aspects of the neuroscience of artistic appreciation. First, I argue that the conceptual foundations underlying much of the current approaches to neuroaesthetics are still problematic and that the experimental approach cannot be applied in any straightforward manner to conduct neuroaesthetic research. I then review some of the most important results of experimental aesthetics and cognitive neurosciences with regard to the mechanisms of aesthetic appreciation before proposing a new neurocognitive model of artistic appreciation based on the notion of an artistic 'task-set' Finally, I end the second part with a theoretical postulate and a neurocognitive framework pertaining to the interactions between mental images and emotions and their possible role in the process of appreciating literary artworks. In the third and final part of the work, I briefly discuss the central ontological preconditions of the neurocognitive studies of art, namely, the neural hypothesis of identity, ‘mind = brain’, and compare it to other approaches of the mind-brain relationship. I also offer a hierarchical model of mental functions based on both the anatomical and the functional aspects of the brain. / Psychology / Ph. D. (Psychology)
525

An investigation into the use of mental imagery by children with autism

Hadfield, Tracy 14 March 2012 (has links)
M.A., Faculty of Humanities, University of the University, 2011 / With the increasing prevalence of autism on a worldwide scale, new teaching methodologies need to be explored in order to educate children with autism helping them to achieve their maximum potential. It has previously been established that many individuals with autism use visual opposed to verbal modes of thinking and learning. In this study action research was used to examine if high imagery instructional methods of teaching could be used as a teaching tool for autistic children attending a special needs school. This study examined whether there was a change in the classroom performance of three autistic children after a 5 month period of high imagery instruction, as compared against a baseline of response to previous instruction, as well as the pattern of verbal and non verbal abilities manifested at time of intake into the programme. Analysis of the results of initial cognitive, language and perceptual tests was thus undertaken for diagnostic purposes, combined with analysis of initial response to teaching prior to high imagery intervention. Once this base-line had been established, analysis of school readiness and scholastic tests was then undertaken pre and post intervention, combined with in-depth interviews with the children’s teacher, analysis of developmental diaries and analysis of work done as part of the school programme followed by each child over a five month period of intervention. At baseline all three children were found to have phonological weaknesses, as evidenced by difficulties isolating onset sounds in words, difficulties with rhyming and difficulties in skills such as blending sounds into words. Two of the children in the sample showed little to no response to the high imagery instruction, and continued to have difficulties with reading and pre-reading tasks involving working with the sound structure of the English language. The third child in the sample showed an increase in phonological skills and in reading, writing and spelling abilities in response to high imagery instruction, as well as an increase in both vocabulary and the non-verbal abilities involved in drawing . It was noted at base-line as well as throughout the study that visual memory was an area of strength for this child, but not for the other two children in the sample. The child who made progress was also able to use his visual strengths to develop associations between sounds and letters. The conclusions from this exploratory study are that not all children with autism learn through use of visual strategies in teaching. The success of high imagery teaching strategies when used with a child with well developed visual memory abilities would suggest that high imagery instruction could be a useful and successful teaching strategy where children with autism exhibit well developed visual modes of thought. Strengths in visual memory and in visual association may be indicators of the likelihood that a child with autism will respond positively to high imagery instruction.
526

Snow cover analysis for the High Drakensberg through remote sensing: Environmental implications

Mulder, Nicholas Andrew Maurits 22 May 2008 (has links)
Snow occurs in the High Drakensberg of southern Africa approximately eight times per annum. Snow cover is frequently captured by Landsat satellite imagery, which provide data for the monitoring of snow cover in other regions of the world. Together with a digital elevation model, repetitive snow cover data are used to analyse the distribution of snow cover in the High Drakensberg study area. The effect that the regional and local topography, latitude, and climatic conditions have on the spatial distribution of snow and the function that temperature, wind, altitude, aspect and slope gradient play in the preservation of snow cover are examined. The results of the spatial study allow for the identification of sites that support the accumulation of snow. Specific active and relict geomorphological features were surveyed and correlated spatially to the contemporary snow cover. Among such features are linear debris ridges on south-facing valley slopes in the High Drakensberg. These appeared similar to glacial features found elsewhere in the world and are thus significant in a long-standing and highly conjectured debate over the validity of possible plateau, cirque and niche glaciation in the region. Late-lying snow cover favours gently sloping south- and southeast-facing aspects at altitudes from 3000 m ASL to just below the highest peaks in the region near 3450 m ASL, above which higher insolation levels on the flat mountain summits provides unfavourable conditions. Snow cover immediately adjacent to the Drakensberg escarpment ablates quickly whilst snow cover at high altitudes in the Lesotho interior experiences better preservation conditions. Latitude has no obvious impact on the distribution of snow cover due to the dominant role of topography in the High Drakensberg other than a limiting of snowfall to regions south of 29°S in late spring. Various synoptic conditions produce snowfall in the region, with cold fronts associated with midlatitude cyclones producing the majority of snow cover. A strong correlation exists between the spatial distribution of snow cover and specific geomorphological features. Observed linear debris ridges are located on slopes that experience frequent contemporary snow cover, lending credence for a glacial origin of the ridges during a period of colder environmental conditions.
527

Modélisation et cartographie de la pollution marine et de la bathymétrie à partir de l'imagerie satellitaire / Modelling and mapping of the pollution marinates and of the bathymetry from the satellite imaging

Bachari Houma, Fouzia 17 December 2009 (has links)
Le contrôle de la qualité de l'eau est fondé naturellement et traditionnellement sur des mesures et des prélèvements in situ. Des images satellites étalonnées à partir des données mesurées in situ fournissent une information quantitative et continue sur le milieu aquatique et peuvent être employées pour estimer, avec une approximation raisonnable, les facteurs affectant la qualité de l’eau L’objectif de ce travail consiste à modéliser les propriétés optiques de l’eau de mer et les paramètres physico-chimiques qui caractérisent les eaux côtières. L'application est basée sur le développement d’un Système d’Information Marin caractérisant un système de gestion de base de données géoréférencié POlGIS dédié à la gestion de l'information marine dans le cas de contrôle, suivi et surveillance de la pollution. Nous présentons des modèles exprimant les variables indicatrices de la qualité des eaux du littoral Algérois et la réflectance calculée de chaque pixel à partir d’un modèle physique de correction radiométrique. Les mesures in- situ sont effectuées pour des zones de différentes qualités d’eaux et leurs réflectances sont calculées à partir des images satellites SPOT, Landsat TM, MSS, IRS1C et Seawifs Finalement, des modèles sont établies avec les réflectances permettent d’obtenir des images satellites indicatrices de la pollution et de la bathymétrie des zones côtières à partir du logiciel de traitement d’image PCSATWIN développé afin d’estimer pour chaque pixel le degré de pollution du milieu. / In order to protect the natural medium and to control the pollution caused by such rejects, it is necessary to achieve a continuous survey of the reject zones. The goal of this study is a developed a methodology for modelling pollution and bathymetry from the digital satellite images.Indeed, our objective consists of the development of a software POLGIS intended for the management of the marine databases for the control and the monitoring of the pollution Satellite imagery can be used to estimate, with a reasonable accuracy, the factors affecting the water quality .It has a great importance to achieve the necessary continuous monitoring of the relevant area with an overall analysis of its pollution. A modelling analysis between the pollution contents and the reflectance calculated by the satellite images allow us to transform rough images into images treated and combined using a software of satellite image processing PCSATWIN developed in this study. This complex phenomena us developed an analytic model of radiatif transfer simulation in water coupled to an atmospheric model in order to simulate measure by satellite. This direct model permits to follow the solar radiance in his trajectory Sun-Atmosphere - Sea - Depth of sea- sensor. The goal of this simulation is to show for every satellite of observation (Spot, Landsat MSS, TM) possibilities that can offer in domain of bathymetry.The reflectance coefficient is calculated from satellite image, the detection and the possible determination of the zones contaminated by pollution using the space techniques constitute an effective means to intervene in order to ensure the monitoring of the Algerian coasts. The analysis shows us that each sensor offers useful information and that the combination between these various informations makes it possible to propose a procedure of maps establishment that can be interpreted as pollution maps.
528

Segmentation sémantique de peuplement forestiers par analyse conjointe d'imagerie multispectrale très haute résolution et de données 3D Lidar aéroportées / Semantic segmentation of forest stand by join analysis of very high resolution multispectral image and 3D airborne Lidar data

Dechesne, Clément 04 December 2017 (has links)
Les peuplements forestiers sont une unité de mesure de base pour l'inventaire forestier et la cartographie. Ils sont définis comme de grandes zones forestières (par exemple, de plus de 2 ha) et de composition homogène en terme d'essence d'arbres et d'âge. Leur délimitation précise est généralement effectuée par des opérateurs humains grâce à une analyse visuelle d'images infrarouges à très haute résolution (VHR). Cette tâche est fastidieuse, nécessite beaucoup de temps et doit être automatisée pour un suivi de l'évolution et une mise à jour efficace. Une méthode fondée sur la fusion des données lidar aéroportées et des images multispectrales VHR est proposée pour la délimitation automatique des peuplements forestiers contenant une essence dominante (pureté supérieure à 75%). C'est une principale tâche préliminaire pour la mise à jour de la base de données de la couverture forestière. Les images multispectrales donnent des informations sur les espèces d'arbres alors que les nuages de point Lidar 3D fournissent des informations géométriques sur les arbres et permettent leur extraction individuelle. Les attributs multimodaux sont calculées, à la fois au niveau des pixels et des objets (groupements de pixels ayant une taille similaire aux arbres). Une classification supervisée est ensuite effectuée au niveau de l'objet afin de discriminer grossièrement les espèces d'arbres existantes dans chaque zone d'intérêt. Les résultats de la classification sont ensuite traités pour obtenir des zones homogènes avec des bordures lisses par la minimisation d'une énergie, où des contraintes supplémentaires sont proposées pour former la fonction énergie à minimiser. Les résultats expérimentaux montrent que la méthode proposée fournit des résultats très satisfaisants en termes d'étiquetage et de délimitation, et ce pour des régions géographiquement très éloignées / Forest stands are the basic units for forest inventory and mapping. Stands are defined as large forested areas (e.g., 2 ha) of homogeneous tree species composition and age. Their accurate delineation is usually performed by human operators through visual analysis of very high resolution (VHR) infra-red images. This task is tedious, highly time consuming, and should be automated for scalability and efficient updating purposes. A method based on the fusion of airborne lidar data and VHR multispectral images is proposed for the automatic delineation of forest stands containing one dominant species (purity superior to 75%). This is the key preliminary task for forest land-cover database update. The multispectral images give information about the tree species whereas 3D lidar point clouds provide geometric information on the trees and allow their individual extraction. Multi-modal features are computed, both at pixel and object levels: the objects are groups of pixels having a size similar to trees. A supervised classification is then performed at the object level in order to coarsely discriminate the existing tree species in each area of interest. The classification results are further processed to obtain homogeneous areas with smooth borders by employing an energy minimum framework, where additional constraints are joined to form the energy function. The experimental results show that the proposed method provides very satisfactory results both in terms of stand labeling and delineation, even for spatially distant regions
529

Meis Oculis: eyes in the early poetry of T.S. Eliot

Unknown Date (has links)
This study is an examination of ocular imagery in the secular poetry of T.S. Eliot. As a symbol, eyes begin as a metonym for the panoptic vision of society. In the earliest poems, Michel Foucault's conceptions of discipline illuminate the acerbic paranoia attached to ocular imagery and its source in the culture of turn-of-the-century Boston. Towards 1919, the image of eyes becomes an objective correlative for the figure of Dante's Beatrice who represents both earthly and divine love. The loss of sight by the various speakers in both - "Gerontion" and The Waste Land is then the loss of connection to both the earthly woman and God. Finally, in The Hollow Men, the tenor and vehicle merge completely so the eyes themselves become the object of desire. / by Joshua RIchards. / Thesis (M.A.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
530

As imagens em palavras: sensações e percepções na leitura de obras da modernidade / The images from words: feelings and perceptions in reading works of modern literature

Santos, Daniela Yuri Uchino 22 May 2015 (has links)
Esta tese tem por objetivo apreender as relações do código verbal nas imagens das palavras, promovendo o resgate da palavra, a qual prescinde do código visual, e que descreve as sensações e percepções diferenciadas e múltiplas, mostradas em níveis graduados, do contextual ao estético; concomitantemente com os traços de modernidade, detectados nas obras selecionadas. O corpus de análise compõe-se de nove obras, dos autores brasileiros tem-se: Bartolomeu Campos de Queirós, Cecília Meireles, Clarice Lispector, Leo Cunha, Lygia Bojunga e Paulo Leminski; dos portugueses, Alice Vieira e José Saramago; e do africano, Mia Couto. Através da observação de algumas características comuns, e buscando-se apoio teórico nos autores que discorreram e discutiram criticamente a modernidade, foram captados tais traços comuns, elencados no primeiro capítulo. O segundo capítulo faz uma pequena incursão sobre os modos de processar a percepção. O terceiro apresenta as análises realizadas, categorizadas em três paradigmas, evidenciando-se os traços de modernidade, cuja presença aparece em menor ou maior grau. Desta forma, o verbal comprova a sua força e seu caráter essencial, que tanto sugere quanto mostra sensações e percepções na leitura da palavra imagética. / This thesis aims at understanding the relationship of verbal code, promoting the rescue of the word, which does without the visual code, the images of words that describe the sensations and differentiated and multiple perceptions, shown in graduated levels of contextual to the aesthetic; concomitantly with traces of modernity, detected in the selected works. The corpus analysis consists of nine works, of Brazilian authors: Bartolomeu Campos de Queirós, Cecília Meireles, Clarice Lispector, Leo Cunha, Lygia Bojunga e Paulo Leminski; of Portuguese Alice Vieira e José Saramago; and African, Mia Couto. By observing some common features, we sought theoretical support in authors who discoursed and critically discussed modernity; raised the features listed in the first chapter. The second chapter makes a small incursion into the ways of processing the perception. The third presents the analyzes, categorized in three paradigms; showing traces of modernity, whose presence appears to a lesser or greater degree. Thus, the verbal proves its strength and its essential character, which both suggests as shows sensations and perceptions in imagetic word reading.

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