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Implementation of Accelerometer-Based Adaptive Noise Cancellation in a Wireless Wearable Pulse Oximeter Platform for Remote Physiological Monitoring and TriageComtois, Gary W. 31 August 2007 (has links)
"A wireless wearable battery-operated pulse oximeter has been developed in our laboratory for field triage applications. The wearable pulse oximeter, which uses a forehead-mounted sensor to provide arterial oxygen saturation (SpO2) and heart rate (HR) information, would enable field medics to monitor vital physiological information following critical injuries, thereby helping to prioritize life saving medical interventions. This study was undertaken to investigate if accelerometry (ACC)-based adaptive noise cancellation (ANC) is effective in minimizing SpO2 and HR errors induced during jogging to simulate certain motion artifacts expected to occur in the field. Preliminary tests confirmed that processing the motion corrupted photoplethysmographic (PPG) signals by simple Least-Mean-Square (LMS) and Recursive Least-Squares (RLS) ANC algorithms can help to improve the signal-to-noise ratio of motion-corrupted PPG signals, thereby reducing SpO2 and HR errors during jogging. The study showed also that the degree of improvement depends on filter order. In addition, we found that it would be more feasible to implement an LMS adaptive filter within an embedded microcontroller environment since the LMS algorithm requires significantly less operations."
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A invisível luz que projeta a sombra do agora: gênero, artefato e epistemologias na arte contemporânea brasileira de autoria negra / The invisible art that projects the shadow of now: genre, artifact and epistemologies in the contemporary brazilian art of black authorshipViana, Janaina Barros Silva 23 August 2018 (has links)
Nesta pesquisa propõe-se o debate sobre aspectos da experimentação em artes visuais pautado no papel do autor e nos discursos traçados pelas relações de identidade e alteridade na arte contemporânea. O retorno à ideia do artista como autor e a individualização dos critérios artísticos ao longo do século XX e XXI tornam-se fundamentais para discutir visualidades em busca de redefinições a respeito das formas de protagonismos no cenário artístico como é o caso de produções associadas diretamente ao epíteto arte afro-brasileira, no sentido em que se refere a produções múltiplas em temas, linguagens, discursos e estratégias de leituras. Traça-se um breve panorama sobre uma cena de autoria negra e seus trânsitos em espaços institucionais nas últimas décadas. Além de apresentar um recorte que considera a leitura da própria pesquisa poética visual. Tem-se como interesse, refletir sobre a construção de epistemologias a partir do debate de gênero e artefato na arte contemporânea. Assim, destacam-se nesta discussão os trabalhos de Rosana Paulino, Sonia Gomes e Lidia Lisboa. O artefato aparece nesta escrita como performance e método: escrita contranarrativa, memória e gesto político. Apresenta a problemática nos lugares de fricção em relação às terminologias instauradas, às condutas poéticas e éticas na arte contemporânea e suas epistemologias. Qual a relevância em sinalizar a origem étnica de uma autoria numa dada forma poética dentro de um contexto histórico e político? Quais movimentos na confuguração de um discurso visual implicam na construção de uma leitura sobre gênero? Quais gestos operativos sinalizam essa condição? De qual maneira nós construímos os nossos olhares e nossas perspectivas nesta encruzilhada sobre a ideia de histórias pessoais e universalidades, microestruturas e macroestruturas? Quando estas autorias falam por si? Qual o lugar possível de legitimidade delas? Quais são as estratégias possíveis de reescritas de contranarrativas? / In this research is proposed a discussion about aspects of experimentation in the visual arts based on the role of the author and in the discourses traced by the relations of identity and otherness in contemporary art. The return to the idea of the artist as na author and the individualization of the artistic criteria along the XX and XXI century become fundamental to discuss the visualities in search of redefinitions about the forms of prominences in the artistic scene as is the case of the productions associated directly to the epithet Afro-Brazilian art, referring to a multiple authorship and its transits in institutional spaces in the last decades is presented. Besides to presenting a clipping that considers the Reading of the own poetic visual research. We have as na interest, to reflect on the construction of epistemologies from the debate of genre and artifact in contemporary art. Thus, the work of Rosana Paulino, Sonia Gomes and Lidia Lisboa stands out in this discussion. The artifact appears in this writing as a performance and method: the counternarrative writing, memory and political motion. It presentes the problematic in the places of epistemologies. What is the relevance of signal the ethnic origino f na author in a certain poetic form within a historical and political contexto? Which movements in the configuration of a visual discourse imply in the construction of a Reading abourt genre? What operative gestures signal this condition? How do we constructo our views and our perspectives at this crossroads about the idea of personal histories and universals, microstructures and macro-structures? When do these authors speak for themselves? What is their possible place of legitimacy? What are the possible rewriting strategies of conter-narratives?
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Méthodes et algorithmes de segmentation et déconvolution d'images pour l'analyse quantitative de Tissue Microarrays / Methods and algorithms of image segmentation and decovolution for quantitative analysis of Tissue MicroarraysNguyễn, Hoài Nam 18 December 2017 (has links)
Ce travail de thèse a pour objectif de développer les méthodes originales pour l'analyse quantitative des images de Tissue Microarrays (TMAs) acquises en fluorescence par des scanners dédiés. Nous avons proposé des contributions en traitement d'images portant sur la segmentation des objets d'intérêts (i.e. des échantillons de tissus sur la lame de TMA scannée), la correction des artefacts d'acquisition liés aux scanners en question ainsi que l'amélioration de la résolution spatiale des images acquises en tenant compte des modalités d'acquisition (imagerie en fluorescence) et la conception des scanners. Les développements permettent d'envisager une nouvelle plateforme d'analyse de TMAs automatisée, qui représente aujourd'hui une forte demande dans la recherche contre les cancers. Les TMAs (ou “puces à tissus”) sont les lames histologiques sur lesquelles de nombreux échantillons tissulaires venant de différents donneurs sont déposés selon une structure de grille afin de faciliter leur identification. Pour pouvoir établir le lien entre chaque échantillon et ses données cliniques correspondantes, on s'intéresse non seulement à segmenter ces échantillons mais encore à retrouver leur position théorique (les indices de ligne et de colonne) sur la grille TMA car cette dernière est souvent très déformée pendant la fabrication des lames. Au lieu de calculer directement les indices de ligne et de colonne (des échantillons), nous avons reformulé ce problème comme un problème d'estimation de la déformation de la grille de TMA théorique à partir du résultat de segmentation en utilisant l'interpolation par splines ''plaques minces''. Nous avons combiné les ondelettes et un modèle d'ellipses paramétriques pour éliminer les fausses alarmes, donc améliorer les résultats de segmentation. Selon la conception des scanners, les images sont acquises pixel par pixel le long de chaque ligne, avec un change de direction lors du balayage entre les deux lignes. Un problème fréquent est le mauvais positionnement des pixels dû à la mauvaise synchronisation des modules mécaniques et électroniques. Nous avons donc proposé une méthode variationnelle pour la correction de ces artefacts en estimant le décalage entre les pixels sur les lignes consécutives. Cette méthode, inspirée du calcul du flot optique, consiste à estimer un champ de vecteurs en minimisant une fonction d'énergie composée d'un terme d'attache aux données non convexe et d'un terme de régularisation convexe. La relaxation quadratique est ainsi utilisée pour découpler le problème original en deux sous-problèmes plus simples à résoudre. Enfin, pour améliorer la résolution spatiale des images acquises qui dépend de la PSF (point spread function) elle-même variant selon le faisceau laser d'excitation, nous avons introduit une méthode de déconvolution d'images en considérant une famille de régulariseurs convexes. Les régulariseurs considérés sont généralisés du concept de la variation parcimonieuses (Sparse Variation) combinant la norme L1 de l'image et la variation totale (Total Variation) pour rehausser les pixels dont l'intensité et le gradient sont non-nuls. Les expériences montrent que l'utilisation de cette régularisation produit des résultats déconvolution d'images très satisfaisants en comparaison avec d'autres approches telles que la variation totale ou la norme de Schatten de la matrice Hessienne. / This thesis aims at developing dedicated methods for quantitative analysis of Tissue Microarray (TMA) images acquired by fluorescence scanners. We addressed there issues in biomedical image processing, including segmentation of objects of interest (i.e. tissue samples), correction of acquisition artifacts during scanning process and improvement of acquired image resolution while taking into account imaging modality and scanner design. The developed algorithms allow to envisage a novel automated platform for TMA analysis, which is highly required in cancer research nowadays. On a TMA slide, multiple tissue samples which are collected from different donors are assembled according to a grid structure to facilitate their identification. In order to establish the link between each sample and its corresponding clinical data, we are not only interested in the localization of these samples but also in the computation of their array (row and column) coordinates according to the design grid because the latter is often very deformed during the manufacturing of TMA slides. However, instead of directly computing array coordinates as existing approach, we proposed to reformulate this problem as the approximation of the deformation of the theoretical TMA grid using “thin plate splines” given the result of tissue sample localization. We combined a wavelet-based detection and a ellipse-based segmentation to eliminate false alarms and thus improving the localization result of tissue samples. According to the scanner design, images are acquired pixel by pixel along each line, with a change of scan direction between two subsequent lines. Such scanning system often suffers from pixel mis-positioning (jitter) due to imperfect synchronization of mechanical and electronic components. To correct these scanning artifacts, we proposed a variational method based on the estimation of pixel displacements on subsequent lines. This method, inspired from optical flow methods, consists in estimating a dense displacement field by minimizing an energy function composed of a nonconvex data fidelity term and a convex regularization term. We used half-quadratic splitting technique to decouple the original problem into two small sub-problems: one is convex and can be solved by standard optimization algorithm, the other is non-convex but can be solved by a complete search. To improve the resolution of acquired fluorescence images, we introduced a method of image deconvolution by considering a family of convex regularizers. The considered regularizers are generalized from the concept of Sparse Variation which combines the L1 norm and Total Variation (TV) to favors the co-localization of high-intensity pixels and high-magnitude gradient. The experiments showed that the proposed regularization approach produces competitive deconvolution results on fluorescence images, compared to those obtained with other approaches such as TV or the Schatten norm of Hessian matrix.
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Artefatos no Jardim da Luz: usos e funções sociais (1870-1930) / Artifacts in Jardim da Luz: usages and social functions (1870-1930)Thais Klarge Minoda 22 November 2017 (has links)
Esta pesquisa propõe analisar o papel o dos artefatos na promoção da sociabilidade no Jardim da Luz, entre os anos de 1870 a 1930. As decisões políticas sobre os espaços públicos verdes tiveram suma importância, pois eram responsáveis pela inserção, reforma ou demolição de artefatos no espaço. Os artefatos, por sua vez, foram muito utilizados na composição das imagens presentes nos cartões postais e circularam pela cidade com o objetivo de exaltar os pontos modernos de São Paulo. No caso do Jardim da Luz, os postais circulados colaboraram para criar o imaginário a respeito do espaço como um local moderno e de sociabilidade. O local passou a ser usado para apresentações musicais, festas e encontros. Foram estudados três principais grupos no espaço: a elite paulistana, os trabalhadores e os fotógrafos lambe-lambe. O Jardim se tornou local representativo para esses grupos, um espaço de festas para alguns e para outros, ambiente de trabalho. Esta pesquisa, pelo estudo da cultura material, pretende compreender os usos dos espaços do Jardim da Luz como um espaço de sociabilidade e suas transformações ao longo do período em questão. / This research intends to analyse urban artifacts\' influence on Jardim da Luz\'s sociability from 1870 to 1930. Political decisions concerning green public spaces had extreme importance on it, as responsibles for artifacts insertion, reform or demolition ion the garden. Artifacts, in turn, were largelly used as background for postcard\'s which circulated through the city to exalt São Paulo\'s modern sights. In Jardim da Luz, Tthose postcards helped to create the ideia of a modern and social place in Jardim da Luz. It had begun to host musical presentations, parties and meetings. In this workstudy, were studied examined three major social groups which attended those events: elite from São Paulo, workers and street photographers. Jardim da Luz became a representative local for those groups, a party place for some and a work site for others. This research, through the study of material culture, intendsaims to understand Jardim da Luz\'s social usage and its transformation through the study of material culture through during the time studied.
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Eliminação de artefatos de estímulo em potenciais evocados somatossensitivos. / Removal of stimulus artifact in somatosensory evoked potentials.Alberto Mitsuo Oyama 09 November 2010 (has links)
Os potenciais evocados têm uma consagrada utilização em clínica. Sua obtenção é dificultada pela presença de outros sinais biológicos, de artefatos de movimento, de ruído eletrônico, de interferência da rede elétrica e de artefatos de estímulo. A média síncrona ou promediação é um método que elimina os sinais que não estejam sincronizados com a estimulação, incluindo os outros sinais biológicos, os artefatos de movimento, o ruído e a interferência. No entanto, esse método não consegue eliminar os artefatos de estímulo. Outros métodos devem ser usados para essa tarefa. Para esses métodos, a eliminação do artefato de estímulo é bem sucedida quando o artefato não se sobrepõe ao potencial evocado. Porém, para uma captação próxima ao local de estimulação, a sobreposição ocorre e dificulta a eliminação do artefato de estímulo. O objetivo deste trabalho foi o de estudar a variação da amplitude e latência do pico do potencial evocado e sua influência nas estimativas da amplitude, da latência e do erro quadrático médio. Para potenciais evocados em que houve sobreposição com o artefato, o erro médio quadrático sempre foi reduzido com a remoção do artefato de estímulo. O erro de medição da latência foi reduzido a praticamente zero, independentemente da amplitude do potencial evocado. Por outro lado, o método inseriu erro na medição da amplitude de potenciais evocados grandes. Por isso, nesse caso específico de atraso pequeno e amplitude grande, a medição da amplitude deve ser feita diretamente no sinal antes da remoção do artefato de estímulo. Comparando a ocorrência de sobreposição com os locais de captação do potencial evocado, pode-se afirmar que, para o modelo de artefato de estímulo usado neste trabalho, a necessidade de se aplicar o procedimento de remoção de artefato se restringiu aos potenciais evocados captados no cotovelo, para estimulação do nervo mediano tanto no punho quanto na mão. / Evoked potentials have been used in clinics. Their measurement is hindered by the presence of other biological signals, movement artifacts, electronic noise, power-line interference, and stimulus artifacts. Synchronous averaging is a method that eliminates the signals that are not synchronized with the stimulation, including other biological signals, movement artifacts, noise and interference. However, this method fails to eliminate stimulus artifacts. Other methods must be used in this task. Using these methods, one can obtain success in the stimulus artifact elimination, whenever the artifact does not superimpose with the evoked potential. Nevertheless, for a measurement close to the stimulation site, the superimposition is a fact that hinders the elimination of the stimulus artifact. The objective of this Masters thesis was to study the variation of the amplitude and latency of an evoked potential and verify their influence on the amplitude and latency estimates, as well as on the mean square error. For evoked potentials in which there was superposition, the mean square error was always reduced by the removal of the stimulus artifact. Latency measurement errors were reduced to zero, regardless of the evoked potential amplitude. However, this method inserted amplitude measurement errors for large evoked potentials. So, in the case of short delays and large amplitudes, amplitude measurements should be performed directly on the signal, before stimulus artifact removal. By comparing the presence of superposition with the evoked potential recording sites, one may state that, for the stimulus artifact model used in this work, the need to apply the artifact removal procedure was restricted to the evoked potentials recorded on the elbow, for median nerve stimulation both on wrist and hand.
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Fragments of the prosperous age : living with heritage and treasure in contemporary ChinaLi, Shuai January 2019 (has links)
This thesis studies contemporary China's heritage boom phenomenon as experienced through the everyday lives of antiquarian communities (collectors, antique dealers etc.) and heritage professionals in and around Beijing. Aiming to extend our vision beyond heritage sites and museums, which constitute the traditional subject of anthropological studies of heritage, the thesis explores the ways in which 'heritage' and 'treasure' are lived by wider Chinese urban residents, constituting a total social fact. Challenging the popular assumption made by heritage scholars in which heritage phenomenon is considered a by-product of modernity's tendency to contrast the current progress with the past as a benchmark, this thesis argues that contemporary China's heritage fever is, however, a social symptom of utopian replacement, in which the idea of linear progress promised by modernisation has been challenged by a recent nationwide utopian project of returning to 'the prosperous age' ('shengshi') with its emphasis on cyclical 'rise and fall'. Treasures of China, as 'Fragments of the Prosperous Age', have thus emerged as powerful imaginaries and resources to open up a utopian vision of ideal society based on fantastic imaginations of China's past glories. Foregrounding the relations between heritage and utopianism, the thesis subsequently investigates the complex ways in which heritage activists from state systems and antiquarian communities contribute to the utopian project from different pathways, bifurcating China's heritage phenomenon into formal and informal parts. Chapters one and two demonstrate that state-led imaginings have changed from the evolutionary perspective to one pursuing the glory of the past under the new spell of 'civilisational revival'. Officials and activists associated with formal heritage deploy a variety of discursive and bureaucratic technologies to securitise, manage and utilise China's ancient treasures, so as to legitimise the current regime. On the other hand, Chapters three and four show that collectors associated with informal heritage encounter fragments of the past in a bodily and joyful way. In ordinary antiquarian practices which juxtapose the cultivation of moral self with the patination of antique objects, collectors pursue an archaic yet neoliberal custodianship which has altered the ethics and sense of moral responsibility in the domains of market exchange. These two factions in China's heritage world may differ from each other in many aspects, but Chapter five suggests both of them, in fact, conspire to reproduce ancient 'prosperous age' ('shengshi') in the present and for the future. The thesis concludes with a discussion about the extent to which Hegel's future-oriented conception of 'capitalised History' that structures the writing of national history has transformed into a 'capitalised Heritage' in contemporary China. 'Capitalised Heritage' works to recast the importance of the Chinese nation in the contemporary world, reaching an ultimate reconciliation with the spectre and material legacies of the past.
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Digital Modeling and Non-Destructive Technological Examination of Artifacts and Safety Harbor Burial Practices at Picnic Mound 8Hi3, Hillsborough County, FloridaMcleod, James Bart 26 March 2014 (has links)
This project reexamines field notes and artifacts from a Works Progress Administration excavation of the Picnic Mound (8Hi3), a Safety Harbor-period burial mound located in Hillsborough County, Florida. The goals are to reconstruct burial practices digitally using a Geographic Information Systems approach to test Ripley Bullen's model of Woodland and Safety Harbor burial practices, and demonstrate ways that modern technologies can be used to provide new information from past investigations. This thesis also presents new information from a pXRF study about prehistoric ceramic manufacturing in the Tampa Bay area, and discusses additional archaeological resources associated with the Picnic Mound. This thesis also illustrates new ways that archaeological materials can be analyzed and exhibited using three-dimensional laser scanning.
Results from the GIS modeling show that burial practices were varied, and cannot be used to assign temporal placement to burial mounds within the Safety Harbor period, as proposed by Bullen. This research illustrates the value of returning to extant archaeological collections and field notes to test models of past human lifeways in a manner that is non-destructive. Information derived from the technologies used for my research can be shared digitally among researchers and can be used to develop materials for public education and furthers additional research efforts.
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The Paleoindian Chipola: A Site Distribution Analysis and Review of Collector Contributions in the Apalachicola River Valley, Northwest FloridaTyler, William D 25 March 2008 (has links)
At the end of the Pleistocene and the beginning of the Holocene, between 12,000 and 10,000 years ago, humans began to spread throughout North America and into many areas of Florida. These first Floridians are known as Paleoindians, and their culture is largely defined by their lithic assemblage, which includes the well known Clovis point. As the Pleistocene ice age came to a close glaciers melted, rivers experienced a drastic increase in water volume and the landmass of Florida began to shrink as the sea level in the Gulf of Mexico rose. This event likely submerged many early Paleoindian sites in coastal areas, and the only sites known now are usually found in river valleys. This research will examine the distribution of Paleoindian sites in the Apalachicola River Valley of northwest Florida in terms of environmental characteristics, namely distance to river and site elevation. Using data from known sites and from four artifact collectors, this research will show that Paleoindian sites cluster along the Chipola River, the major tributary of the Apalachicola River, and will also argue that it is far more beneficial for archaeologists to work with artifact collectors and document their vast amounts of data than to shun them and deem their data questionable and their methods unethical.
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Uncovering the Hidden Co-Evolution in the Work History of Software ProjectsBala, Saimir, Revoredo, Kate, Goncalves, Joao Carlos de A. R., Baiao, Fernanda, Mendling, Jan, Santoro, Flavia January 2017 (has links) (PDF)
The monitoring of project-oriented business processes is difficult because their state is fragmented and represented by the progress
of different documents and artifacts being worked on. This observation holds in particular for software development projects in which various
developers work on different parts of the software concurrently. Prior contributions in this area have proposed a plethora of techniques to analyze
and visualize the current state of the software artifact as a product. It is surprising that these techniques are missing to provide insights into what
types of work are conducted at different stages of the project and how they are dependent upon another. In this paper, we address this research gap and present a technique for mining the software process including
dependencies between artifacts. Our evaluation of various open-source projects demonstrates the applicability of our technique.
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Investigating Second Seminole War Sites in Florida: Identification Through Limited TestingBell, Christine 19 November 2004 (has links)
This thesis uses the results of limited testing at the Fort Dade (1836-1842) and Hope Homestead (1842-ca. 1900) archaeological sites to establish a method for quickly identifying threatened sites with minimal disturbance to surrounding areas. Artifact analysis, pattern recognition, and comparison with similar known sites are key elements. Pedestrian survey, metal detection, posthole and shovel testing, and test excavation are tools used to accomplish this. Artifact analysis is used to establish date ranges for the sites, as well as the material variation between military and homestead occupations. Artifacts used for analysis include glass, ceramics, nails, arms and personal items. Quantitative analysis of artifact assemblages is utilized to determine broad site type classification, and further contribute to preliminary identification. Correspondence analysis helps differentiate sites according to length and type of occupation. With refinement, this method could be used for preliminary identification of many Seminole War sites. Rapid and widespread development in Florida has made identification of Seminole War sites a priority, so they can be recorded and preserved before they are lost forever.
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