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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.
71

Design of a Smartphone-Camera-based Fluorescence Imaging System for the Detection of Oral Cancer

Uthoff, Ross January 2015 (has links)
Shown is the design of the Smartphone Oral Cancer Detection System (SOCeeDS). The SOCeeDS attaches to a smartphone and utilizes its embedded imaging optics and sensors to capture images of the oral cavity to detect oral cancer. Violet illumination sources excite the oral tissues to induce fluorescence. Images are captured with the smartphone’s onboard camera. Areas where the tissues of the oral cavity are darkened signify an absence of fluorescence signal, indicating breakdown in tissue structure brought by precancerous or cancerous conditions. With this data the patient can seek further testing and diagnosis as needed. Proliferation of this device will allow communities with limited access to healthcare professionals a tool to detect cancer in its early stages, increasing the likelihood of cancer reversal.
72

Le miroir d'un archevêque : étude autour du pontifical de Pierre de la Jugie (Narbonne, Trésor de la cathédrale, ms. 2) / The mirror of an archbishop : research around the pontifical of Pierre de la Jugie (Narbonne, Trésor de la cathédrale, ms. 2)

Nadal, Emilie 02 December 2013 (has links)
En 1350, Pierre de la Jugie, neveu du pape Clément VI, est depuis trois ans sur le siège de Narbonne, à la tête d’un des archevêchés les plus riches du royaume de France, lorsqu’il décide de faire réaliser un pontifical à la hauteur de ses ambitions. Orné de 24 médaillons pour le calendrier, d’une pleine page, et de 61 lettres historiées encore en place (une vingtaine a été découpé), l’ouvrage est un témoignage exceptionnel, bien documenté, qui permet de comprendre les modalités de la commande des manuscrits liturgiques enluminés au XIVe siècle, et qu’il est possible de replacer dans un contexte politique, religieux et artistique bien déterminé. Le livre n’est qu’en partie fidèle au modèle de pontifical établi par Guillaume Durand. Outre un calendrier et des feuillets de comput, il contient aussi plusieurs textes additionnels, expressément ajoutés par Pierre de la Jugie pour certains d’entre eux, et accompagné d’une iconographie qui leur est propre. L’étude des textes, du calendrier au pontifical, et de l’iconographie choisie pour les illustrer, permet de mettre en valeur la forte implication du commanditaire dans la mise en place de ce livre. Les peintures qui ornent ces pages sont l’œuvre de quatre artistes qui, en dépit de leurs formations différentes (Catalogne, Sud de la France, Italie) ont collaboré et se sont mutuellement influencés. Le recensement des productions de chacun des enlumineurs permet enfin de mettre en valeur l’existence de réseaux d’échanges entre les artistes et les commanditaires ecclésiastiques appartenant à un même clan de prélats limousins. / In 1350 , Pierre de la Jugie, archbishop of Narbonne and nephew of Pope Clement VI, decides to make a Pontifical that lives up to his ambitions. Decorated with 24 medallions for the calendar, a full page and 61 historiated letters, the book is an exceptional testimony, well documented, which helps to understand the ways liturgical illuminated manuscripts were ordered during the fourteenth century, and it can be replaced in a well-defined political, religious and artistic context. In addition to a calendar, and computus, this pontifical of Guillaume Durand also contains several additional texts, specifically added by Pierre de la Jugie for some of them, and accompanied by an iconography of their own. The study of the text and iconography highlights the strong involvement of the ecclesiastical patron in the creation of this book. The paintings that adorn these pages are the work of four artists who, despite their different backgrounds (Catalonia, southern France, Italy) have collaborated and influenced each other. The census of production of each of illuminators can finally highlight the existence of exchanges between artists and church patrons belonging to the same clan prelates Limousin networks.
73

Temporal effects in glare response

Kent, Michael G. January 2016 (has links)
Discomfort glare is considered to be an annoyance or distraction caused by sources of non-uniform or high luminance within the field of view of an observer. There are still significant gaps in our understanding of the conditions that characterise the magnitude and occurrence of discomfort glare, this being especially evident in the presence of large sources of luminance such as windows. The large degree of scatter that is observed when subjective evaluations of glare sensation are compared against calculated glare indices suggests that discomfort glare may be dependent on other variables beyond the physical and photometric parameters that are commonly embedded in glare formulae (e.g., source luminance, source size, background luminance, and position index). There are strong reasons to believe that some of these variables might be linked to the time of day when the observer is exposed to the glare source. In response, this thesis investigated the research hypothesis that subjective glare sensation is associated with temporal variability. This hypothesis was tested in two stages. The first stage was conducted within a laboratory setting, and sought to examine temporal effects under controlled artificial lighting conditions. The collection of temporal variables and personal factors – thereby examining the scatter in glare responses across the independent variable (time of day) and isolating potential confounding variables – enabled to identify factors that could influence the subjective evaluation of glare sensation along the day. Having established the presence of a temporal effect on glare response, the influences detected were further explored within a test room with direct access to daylight, whereby temporal variables and personal factors were measured in conjunction to glare sensation for them to be statistically masked from the analysis. The results confirmed the hypothesis of an increased tolerance to glare as the day progresses. This supported the conclusion that physical and photometric parameters alone are not sufficient for a robust prediction of discomfort glare.
74

Classification of sets of mixed pixels in remote sensing

Faraklioti, M. January 2000 (has links)
Recently, remotely sensed multispectral data have been proved to be very useful for many applications in the field of Earth surveys. For certain applications, however, limits in the spatial resolution of satellite sensors and variation in ground surface restrict the usefulness of the available data, since the observed spectral signature of the pixels is the result of a number of surface materials found in the area of the pixel. Two mixed pixel classification techniques which have shown high correlation with vegetation coverage of single pixels are described in this thesis: the vegetation indices and the linear mixing model. The two approaches are adjusted in order to deal with sets of pixels and not individual pixels. The sets of pixels are treated as statistical distributions and moments can be estimated. The vegetation indices and the linear mixing model can then be expressed in terms of these statistics. The illumination direction is an important factor that should be taken into account in mixed pixel classification, since it modifies the statistics of the distributions of pixels, and has received no attention until now. The effect of illumination on the relation between the vegetation indices and the proportion of sets of mixed pixels is examined. It is demonstrated that some vegetation indices, which are defined from the ratio of statistics in two spectral bands, can be considered relatively invariant to illumination changes. Finally, a new illumination invariant mixing model is proposed which is expressed in terms of some photometric invariant statistics. It is shown to perform very well and it can be used to un-mix accurately sets of pixels under many illumination angles. The newly introduced mixing model can be considered a suitable choice in the mixed pixel classification field. Key words: Mixed pixels, sets of pixels, vegetation index, illumination invariants.
75

Opening the senses : the Gospel book as an instrument of salvation as articulated by the minor decoration and full-page illustrations of the Book of Kells

Pulliam, Heather January 1998 (has links)
This thesis argues that the minor decoration and full-page images of the Book of Kells reflects a cohesive theme: the role of the gospel book in man's apprehension of God. This is demonstrated by an examination of the decorated initials and smaller images in relation to the text and a reinterpretation of the full-page images within the context of patristic commentary and the writings of the period. It is argued that the decorated initials and minor imagery are not merely ornamental but instead emphasize and comment upon the text. They do so in three ways: Firstly, they draw the eye to passages of gospel text that describe the visual apprehension and recognition of Christ as the Son of God. In demonstrating this, the assumption that the decorated initials operate in a traditional manner, such as marking lections or Eusebian sections, is rejected. The atypical function of the decoration, highlighting themes rather than liturgical or content divisions, indicates the unique function of the manuscript. Secondly, it is argued that the decorated initials employ the metaphorical imagery of the Psalms to describe the distinction between the manuscript's audience who acknowledge Christ as the Son of God, and those described within the text as confused and unable to recognize the identity of Christ despite his presence in their midst. Thirdly, the imagery of the decorated initials describes the manner in which the Godhead is literally contained within the text of the gospel book. The larger images also emphasize the recognition of Christ and distinguish between those who look to the Word of God and those who fail to do so. Additionally, the full-page imagery instructs the audience in the use of the manuscript. To an even greater extent than the minor decoration, the larger images articulate the role of the Gospel book and liturgy as a visible guide to an invisible deity and shield against temptation.
76

On the constant of homothety for covering a convex set with its smaller copies

Naszódi, Márton 25 September 2017 (has links)
No description available.
77

Comportamento de prateleira de luz em modelo fisico sob ceu real na cidade de Campinas, SP / Behavior of light shelf in physical model under real sky in the city of Campinas, SP

Rosim, Camila Aldriguetti, Scarazzato, Paulo Sérgio, 1954- 12 August 2018 (has links)
Orientadores: Mauricio Roriz, Paulo Sergio Scarazzato / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-12T07:07:29Z (GMT). No. of bitstreams: 1 Scarazzato_PauloSergio_M.pdf: 1298030 bytes, checksum: ed6a14898133297e6bf5adc07cbe1fb4 (MD5) Previous issue date: 2008 / Resumo: A utilização de iluminação natural, por meio de aberturas laterais é quase inevitável nas edificações. No entanto, da forma convencional como vêm sendo projetadas e construídas, estas aberturas podem apresentar desempenho bastante insatisfatório, particularmente em relação à má distribuição das iluminâncias internas e aos significativos níveis de ganhos térmicos. Esta Dissertação de Mestrado apresenta uma pesquisa que, através da análise de dados medidos em modelo físico, montado na cidade Campinas, Estado de São Paulo, objetivou identificar os parâmetros principais que interferem no comportamento de prateleiras de luz. Essas são elementos que redirecionam a luz solar para o interior dos ambientes, especialmente para as regiões mais distantes das janelas, muitas vezes insuficientemente iluminadas e que, ao mesmo tempo, atenuam o excesso de radiação nas regiões mais próximas das fachadas, reduzindo, assim, os contrastes entre áreas mais claras e mais escuras. O experimento foi realizado com monitoramento simultâneo de iluminâncias externas e internas ao modelo em escala, sob as condições reais do céu local. Foram estudados seis sistemas de prateleiras: branca horizontal, branca com quatro diferentes inclinações e espelhada horizontal. Foram elaboradas comparações entre os desempenhos apresentados por estas seis tipologias, bem como entre seus resultados e aqueles observados em sistemas tradicionais de aberturas laterais, sem qualquer elemento de redirecionamento da luz. Adicionalmente, os valores medidos foram também comparados com outros dados experimentais, disponíveis no software DLN - Disponibilidade de Luz Natural. / Abstract: The use of day lighting through lateral openings is almost inevitable in the constructions. However, in the conventional form as they come being projected and constructed, these openings present sufficiently unsatisfactory performance, particularly in relation to bad distribution of the internal luminance and to the significant levels of thermal profits. This work of graduate presents a research that, through the analysis of measured data in physical model mounted in the Campinas city, state of São Paulo, it objectified to identify the main parameters that intervene with the behavior of light shelves. These are elements that redirect the solar light for the interior of environments, especially for the regions most distant of the windows, many times insufficiently illuminated and that, in the same time, attenuate the excess of radiation in the regions next to the feats, thus reducing the contrasts between clearer and darker areas. The experiment was carried through with simultaneous watching of external and internal luminance to the model in scale, under the real conditions of the local sky. Six systems of shelves, horizontal white, white with four different inclinations and horizontal mirror surface had been studied. Had been elaborated comparisons between the performances presented for these six typologies, as well as between its results and the observed ones in traditional systems of lateral openings, without any element of redirectioning of the light. Additionally, the measured values also had been compared with other experimental data, available in software "DLN" - Availability of Natural Light. / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil
78

Active Illumination for the RealWorld

Achar, Supreeth 01 July 2017 (has links)
Active illumination systems use a controllable light source and a light sensor to measure properties of a scene. For such a system to work reliably across a wide range of environments it must be able to handle the effects of global light transport, bright ambient light, interference from other active illumination devices, defocus, and scene motion. The goal of this thesis is to develop computational techniques and hardware arrangements to make active illumination devices based on commodity-grade components that work under real world conditions. We aim to combine the robustness of a scanning laser rangefinder with the speed, measurement density, compactness, and economy of a consumer depth camera. Towards this end, we have made four contributions. The first is a computational technique for compensating for the effects of motion while separating the direct and global components of illumination. The second is a method that combines triangulation and depth from illumination defocus cues to increase the working range of a projector-camera system. The third is a new active illumination device that can efficiently image the epipolar component of light transport between a source and sensor. The device can measure depth using active stereo or structured light and is robust to many global light transport effects. Most importantly, it works outdoors in bright sunlight despite using a low power source. Finally, we extend the proposed epipolar-only imaging technique to time-of-flight sensing and build a low-power sensor that is robust to sunlight, global illumination, multi-device interference, and camera shake. We believe that the algorithms and sensors proposed and developed in this thesis could find applications in a diverse set of fields including mobile robotics, medical imaging, gesture recognition, and agriculture.
79

Significance of dot-patterns in Carolingian manuscripts

Morris, Inga Dengler January 1965 (has links)
The significance of dot patterns in Carolingian manuscripts is the subject of my research. In my investigation into the sources of these patterns I hope to show some relationship between them and metal working techniques to which could be attributed an overall development of pattern and design during the early Middle Ages. Since the art of the period reflects so strongly the social and political conditions existent during the reign of Charlemagne I have also included a brief summary of those relevant historical conditions. The adverse situation prevailing in the Frankish kingdom during the seventh century together with the weakness of its rulers enabled the Carolingian family to obtain power, and when Charlemagne became the sole ruler in 771 he continued to carry out the family policy of uniting the peoples of the West and initiated a revival of Roman culture and learning in his kingdom. This programme also included the establishment of schools, and the illumination of books; also to fit into his ambitious programme every effort was directed by both Church and state to produce a variation in the artistic world from the then available migration art. To accomplish this foreign artists and their work were readily drawn to the court of Charlemagne to contribute to the new form of artistic expression; while the Church did its part by adapting foreign and domestic styles in its newer designs and by utilizing the working methods of the monastic workshops. From my investigation I find that the dot patterns are only used in the manuscripts of some Carolingian schools notably the School of Tours, which is generally recognised as the oldest school. Examination of these manuscripts proves there are many variations in the patterns of dots used, the reason for which is sought in the influences and inspirations of the following: 1. Foreign styles, including Insular and Eastern Mediterranean art forms. 2. Applied arts. Here I find that dottings can be listed according to their origins in metal working techniques. Finally the origin is sought of the peripheral dottings found particularly in connection with Canon Tables; and references are given to various sources of influence from the Eastern Mediterranean arts together with one example from an Irish church. I reach the conclusion that the influences governing the dot patterns in Carolingian manuscripts came from many sources and that the dot patterns were ultimately combined and moulded into new designs through the working procedures developed in the Scriptorium. In my collation of all the available evidence I establish the fact that these dot patterns are presented in three main groups: 1. Dots derived from constructional details of domestic artifacts. 2. Dots derived from decoration of the above. 3. Dots derived from imported manuscripts, ivories, and so on. My final suggestion is that the dottings of foreign origin become absorbed very rapidly in the style that borrowed them, while the dottings derived from well known objects seem to disappear entirely for two apparent reasons: 1. The art from which they sprang begins to deteriorate. 2. Society changes; and with the arrival of other values the objects copied are no longer of major importance. / Arts, Faculty of / Art History, Visual Art and Theory, Department of / Graduate
80

Active scene illumination metods for privacy-preserving indoor occupant localization

Zhao, Jinyuan 29 September 2019 (has links)
Indoor occupant localization is a key component of location-based smart-space applications. Such applications are expected to save energy and provide productivity gains and health benefits. Many traditional camera-based indoor localization systems use visual information to detect and analyze the states of room occupants. These systems, however, may not be acceptable in privacy-sensitive scenarios since high-resolution images may reveal room and occupant details to eavesdroppers. To address visual privacy concerns, approaches have been developed using extremely-low-resolution light sensors, which provide limited visual information and preserve privacy even if hacked. These systems preserve visual privacy and are reasonably accurate, but they fail in the presence of noise and ambient light changes. This dissertation focuses on two-dimensional localization of an occupant on the floor plane, where three goals are considered in the development of an indoor localization system: accuracy, robustness and visual privacy preservation. Unlike techniques that preserve user privacy by degrading full-resolution data, this dissertation focuses on an array of single-pixel light sensors. Furthermore, to make the system robust to noise, ambient light changes and sensor failures, the scene is actively illuminated by modulating an array of LED light sources, which allows algorithms to use light transported from sources to sensors (described as light transport matrix) instead of raw sensor readings. Finally, to assure accurate localization, both principled model-based algorithms and learning-based approaches via active scene illumination are proposed. In the proposed model-based algorithm, the appearance of an object is modeled as a change in floor reflectivity in some area. A ridge regression algorithm is developed to estimate the change of floor reflectivity from change in the light transport matrix caused by appearance of the object. The region of largest reflectivity change identifies object location. Experimental validation demonstrates that the proposed algorithm can accurately localize both flat objects and human occupants, and is robust to noise, illumination changes and sensor failures. In addition, a sensor design using aperture grids is proposed which further improves localization accuracy. As for learning-based approaches, this dissertation proposes a convolutional neural network, which reshapes the input light transport matrix to take advantage of spatial correlations between sensors. As a result, the proposed network can accurately localize human occupants in both simulations and the real testbed with a small number of training samples. Moreover, unlike model-based approaches, the proposed network does not require modeling assumptions or knowledge of room, sources and sensors.

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