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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.
341

Avaliação do potencial fisiológico de sementes de pepino utilizando sistema computadorizado de análise de imagens de plântulas (SVISR), em comparação com procedimentos tradicionais / Assessment of the physiological quality of cucumber seeds by an automated computer imaging system (SVIS®), compared to traditional procedures

Chiquito, Adrielle Aparecida 27 June 2011 (has links)
O presente trabalho teve como objetivo avaliar a eficiência do sistema de análise de imagens de plântulas (Seedling Vigor Imaging System® - SVIS®) na determinação do potencial fisiológico de sementes de pepino, em comparação com informações fornecidas por testes de vigor recomendados para essa espécie. O trabalho foi desenvolvido em três épocas de avaliação com intervalos aproximados de três meses. Em cada época, a avaliação do potencial fisiológico foi efetuada usando-se os testes de germinação, primeira contagem de germinação, envelhecimento acelerado tradicional e com solução saturada de NaCl, comprimento de plântulas e emergência de plântulas. Os resultados desses testes foram comparados com os dados obtidos com o uso do software Seedling Vigor Imaging System (SVIS®), que avaliou o desenvolvimento de plântulas escaneadas, mediante a obtenção de valores do comprimento da raiz primária, do hipocótilo e das plântulas, do índice de vigor e de uniformidade de desenvolvimento. Além disso, foram estudadas variações na proporção da participação do crescimento e da uniformidade de desenvolvimento das plântulas para o cálculo do índice de vigor no \"software SVIS®, na tentativa de verificar possíveis variações na sensibilidade do sistema para detectar diferenças no potencial fisiológico dos lotes avaliados. Concluiu-se que a análise computadorizada de imagens de plântulas é uma alternativa consistente e promissora para avaliação do potencial fisiológico de sementes de pepino, com eficiência comprovada equivalente à verificada em testes tradicionais para determinação do vigor. As análises pelo SVIS® em plântulas com quatro dias de idade são mais precisas e a proporção crescimento/uniformidade para a composição do cálculo do índice de vigor não afeta a precisão da determinação do potencial fisiológico de sementes de pepino pela análise SVIS®. / This study aimed to evaluate the efficiency of seedling digital image analysis (Seedling Vigor Imaging System® - SVIS®) to determine the physiological quality of cucumber seed lots, compared to information provided by vigor tests recommended for this species. Research comprised three evaluation times with a threemonth interval. Physiological quality determination comprised germination, germination first count, traditional and saturated salt accelerated aging, seedling length and seedling emergence tests. Results obtained were compared to data by the evaluation using the software Seedling Vigor Imaging System (SVIS®); in this system, seedlings were scanned and the image analysis made possible to obtain values of the primary root, hypocotyl and seedling lengths in addition to a vigor index and uniformity of seedling of development. It also studied the importance of the contribution of growth intensity and uniformity to compose the value of the vigor index calculated by the software. It was concluded that digital image analysis of seedlings is a consistent and promising alternative to provide reliable information of cucumber seed physiological quality, comparable to those from traditional tests. Analyses by SVIS ® of four-day old seedlings are more accurate, and the proportion growth/uniformity in the composition of the vigor index does not affect the accuracy of determining the physiological quality of cucumber seeds by analyses SVIS®.
342

Image analysis of retinal vascular network geometry and its relationship to cardiovascular complications. / 圖像分析視網膜血管網的特徵及其與心血管疾病的關係 / CUHK electronic theses & dissertations collection / Tu xiang fen xi shi wang mo xue guan wang de te zheng ji qi yu xin xue guan ji bing de guan xi

January 2012 (has links)
目的1)發現與中風相闋的視網膜特徵2) 利用視網膜特徵建立統計模型對老年人中風風險進行分類。 / 方法:配對病例對照研究。病例為中風患者,一部分中風患者來自於糖尿病眼病的篩查項目,另外一部分是腦內科的中風患者。對照是沒有中風的老年人。對照來自糖尿病眼病篩查項目內沒有患中風的患者及在眼科門診沒有中風及特殊眼病的患者。對照與病例在年齡及是否患有糖尿病進行匹配。所有研究對象均來自香港威爾斯親王醫院。我們收集所有研究對象的中風危險因素,包括年齡,性別,吸煙,及是否患有糖尿病,高血壓,缺血性心髒病,心房顫動,高血脂。所有研究對象的彩色視網膜照片都被採集。我們應用軟件“ImageJ"分析並記錄視網膜動靜脈直徑,血管分叉係數,分叉角度,分叉對稱性,視乳頭周長。我們也記錄其他視網膜特徵,如動靜脈壓跡,出血,硬性滲出,動脈阻塞及血管彎曲性。獨立t檢驗用於對連續變量的單因素分析,卡方檢驗用於對分類變量的單因素分析。Logistic 回歸用於建立統計模型對中風風險進行分類。所有統計方法均應用SPSS16.0 軟件。 / 結果:本研究納入122 中風患者及122 例患者做對照。每組分別有81 例糖尿病患者, 41 例非糖尿病患者。視網膜特徵包括動靜脈直徑,血管彎曲度,出血,硬性滲出,動靜脈壓跡在兩組中有顯著性差異。我們建立風險模型對兩組患者進行風險分類。分類準確度最高達的模型裡面包括的因子有:1)中風相關危險因素包括:高血壓,糖尿病,心房顫動2) 視網膜特徵包括:動脈直徑,血管彎曲性,出血,動靜脈壓跡跟靜脈對稱性;3) 視網膜特徵間的交立作用包括:動脈直徑與靜脈對稱性,動脈直徑與出血,靜脈對稱性與血管彎曲度。分類的準確度為80 .4%。只包括視網膜特徵的分類模型的準確度為74.5% 。 / 結論:彩色視網膜照相可成為中風風險的分類工具。與中風相關的視網膜特徵包括血管直徑,血管彎曲度,血管對稱性,出血,動靜脈壓跡。視網膜特徵與中風之間的聯繫存在交互作用。 / Objective: 1) To detect retina characteristics that associated with stroke; 2) To develop a statistics model with variables of retina characteristics for classifying patients with stroke from those without stroke in aged population. / Method: Matched case control study. Patients with stroke from the diabetic retinopathy screening program and stroke patients from Acute Stroke Unit were selected as stroke cases. Controls (patients without history of stroke) with matched diabetes status and age were selected from the diabetic retinopathy screening program and eye outpatient clinics. All subjects in this study were from Prince of Wales Hospital, Hong Kong. Risk factors of stroke from all subjects were collected, including age, gender, diabetes, hypertension, hyperlipidemia, history of ischemic heart disease, atrial fibrillation and smoking. Color retina images of each subject were collected and analyzed. The retina characteristics, including diameters of arterioles and venules, bifurcation coefficients, bifurcation angles, branch symmetry, optic disc perimeter were extracted from the color retina images by software "ImageJ". Other retina characteristics including arteriole-venule nicking, hemorrhages, exudates, arteriole occlusion, and vessel tortuosity were also recorded. Independent t test and Chi-squire test were used to compare the continuous and categorical retina characteristics respectively between patients with stroke and those without stroke. Logistic model combining the risk factors of stroke and retina characteristics was established to classify patients with stroke from those without stroke. All data analysis was by SPSS 16.0. / Results: there were 122 stroke cases and 122 controls recruited in this study. There were 41 patients without diabetes and 81 patients with diabetes in each group. Retina characteristics including diameters of arterioles and venules, vessel tortuosity, hemorrhages, exudates, arteriole-venule nicking were significantly different between the two groups. We established risk models to classify patients with stroke from those without stroke. The risk model with highest accuracy of classification included 1) stroke risk factors including hypertension, diabetes and atrial fibrillation; 2) retina characteristics, including arteriole diameters, vessel tortuosity, hemorrhages, arteriolevenule nicking and venule symmetry; 3)interaction between retina characteristics, including arteriole diameters by venule symmetry, arteriole diameters by hemorrhage,and venule symmetry by vessel tortuosity. The accuracy of classification was 80.4%. Using retinal characteristics alone achieved an accuracy of 74.5%. / Conclusion: color retina images are a potential tool for stroke risk stratification. Useful characteristics found in the retinal images included vessel diameters, vessel tortuosity, vessel symmetry, hemorrhage, arteriole-venule nicking. The association between the retinal characteristic and stroke was modified by other retinal characteristics. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Qing. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 139-148). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.iii / Acknoledgements --- p.v / Chapter Chapter 1 --- Introduction and review of the Literature --- p.1 / Chapter Section 1: --- Stroke prevention and risk assessment tools --- p.1 / Chapter Section 2: --- Rationale of relationship of vascular circulation between retina and brain --- p.9 / Chapter Section 3: --- Manifestation of hypertensive retinopathy and diabetic retinopathy --- p.12 / Chapter Section 4: --- Retina characteristics related to stroke --- p.15 / Chapter Section 5: --- How to make retina as a tool of risk stratification for stroke --- p.28 / Chapter Section 6: --- Rationale to do study to further explore the useful information in color retina images to make it as tool for stroke risk stratification --- p.31 / Chapter Chapter 2 --- Research hypothesis and general design --- p.33 / Chapter Chapter 3 --- Methods of retia characteristics extraction --- p.34 / Chapter Chapter 4 --- A Study of the Reliability of manual measurement of Retinal characteristics using ImageJ --- p.46 / Chapter Chapter 5 --- A study of comparison of retina characteristics between patients with stroke and patients without stroke --- p.55 / Chapter Section 1: --- Method --- p.56 / Chapter Section 2: --- Result-univariate analysis --- p.62 / Chapter Section 3: --- Results-stratification analysis --- p.68 / Chapter Section 4: --- Result-risk model building for stroke risk stratification --- p.79 / Chapter Chapter 6: --- Discussion --- p.118 / Chapter Chapter 7: --- Limitation of this study --- p.133 / Chapter Chapter 8: --- Future development and application of the study results --- p.134 / Appendix --- p.136 / Reference --- p.139
343

Processo de agregação e ruptura : estudo experimental com carvão ativado e modelagem matemática por balanço populacional

Barcellos, Brunna Samuel de Carvalho January 2016 (has links)
Em um tratamento de águas de abastecimento ou residuárias, a coagulação/floculação é um processo de grande importância. A determinação dos agentes coagulante/floculante e a quantidade necessária de cada um deles são problemas rotineiros para os profissionais e podem influenciar na qualidade do tratamento. Determinar o tamanho dos flocos é fundamental para que a operação de floculação ocorra com melhor eficiência. Ainda, variáveis hidrodinâmicas, como a velocidade, volume das partículas e do recipiente, também têm a mesma importância nesta finalidade. No presente trabalho, a modelagem do processo de floculação via balanço populacional foi estudada com o objetivo de prever a formação de agregados/flocos em relação com o tempo até atingir o estado estacionário e em condições de operação distintas. Assim, um modelo de balanço populacional pela técnica de discretização por pivô fixo foi implementado no software EMSO. Um estudo foi realizado através de processamento/análise de imagens capturadas em um experimento de coagulação/floculação. As imagens obtidas do processo de floculação foram analisadas e foi verificado a distribuição do tamanho dos flocos. Com os dados de volume e concentração inicial de partículas foi possível a simulação no modelo matemático. Assim tornou-se possível observar o crescimento, a estabilização, o comportamento dos flocos em comparação com o modelo matemático e a frequência desses flocos em cada tamanho em diferentes condições, como o gradiente de velocidade e a concentração inicial de partículas. Os resultados obtidos em comparação com os dados experimentais e a simulação do modelo matemático foram possíveis verificar comportamento semelhante de distribuição de tamanho de flocos. A partir dessa análise, o modelo matemático mostrou-se satisfatório em prever o comportamento experimental. Em diferentes condições pode-se verificar que o gradiente de velocidade e a concentração inicial de partículas influenciam na formação e estabilização dos flocos. Este estudo teve a utilização de softwares de livre acesso para trazer a proposta de implementação a fim de trazer economia de agentes químicos utilizados e melhoria nos processos de operação da estação tratamento de efluentes. / In a wastewater treatment, coagulation / flocculation is a process of great importance. The determination of coagulant / flocculant agent and the required amount of each problems are routine for professional and can influence the quality of treatment. Determination the flocs size is essential for flocculation operation to occur with greater efficiency. Still, hydrodynamic variables, such as speed, particles volume and the container also have the same importance in this purpose. In the present work, modeling of flocculation process by population balance was studied in order to predict the formation of aggregates / flocs in relation to time to reach steady state and at different operating conditions. Thus, a population balance model by discretization technique for fixed pivot was implemented in EMSO software. A study was conducted through the processing / analysis of images captured on an experiment coagulation / flocculation. Images obtained in the flocculation process were analyzed and it was found the size distribution of flocs. With the volume and initial particle concentration values, simulation was possible in mathematical model. Thus it became possible to observe the growth, establization and behavior of flocs in comparison with the mathematical model, and the frequency of such flocs in each size in different conditions, such as the velocity gradient and the initial particle concentration. The results obtained in comparison to experimental data and simulation of the mathematical model we observed behavior flocs size distribution similar. From this analysis, mathematical model was satisfactory to predict the experimental behavior. Under different conditions can be seen that the velocity gradient and the initial concentration of particles influence the formation and stabilization of flocs. This study was the use of software-free access to bring the implementation of proposal in order to bring savings of chemicals used and improvement in operating processes of wastewater treatment station.
344

Adaptive Quantification and Subtyping of Pulmonary Emphysema on Computed Tomography

Häme, Yrjö January 2015 (has links)
Pulmonary emphysema contributes to the chronic airflow limitation characteristic of chronic obstructive pulmonary disease (COPD), which is a leading cause of morbidity and mortality worldwide. Computed tomography (CT) has enabled in vivo assessment of pulmonary emphysema at the macroscopic level, and is commonly used to identify and assess the extent of the disease. During the past decade, the availability of CT imaging data has increased rapidly, while the image quality has continued to improve. High-resolution CT is extremely valuable both for patient diagnosis and for studying diseases at the population level. However, visual assessment of these large data sets is subjective, inefficient, and expensive. This has increased the demand for objective, automatic, and reproducible image analysis methods. For the assessment of pulmonary emphysema on CT, computational models usually aim either to give a measure of the extent of the disease, or to categorize the emphysema subtypes apparent in a scan. The standard methods for quantitating emphysema extent are widely used, but they remain sensitive to changes in imaging protocols and patient inspiration level. For computational subtyping of emphysema, the methods remain at a developmental stage, and one of the main challenges is the lack of reliable label data. Furthermore, the classic emphysema subtypes were defined on autopsy before the availability of CT and could be considered outdated. There is also no consensus on how to match the subtypes on autopsy to the varying emphysema patterns present on CT. This work presents two methodological improvements for analyzing emphysema on CT. For the assessment of emphysema extent, a novel probabilistic approach is introduced and evaluated on a longitudinal data set with varying imaging protocols. The presented model is shown to improve significantly compared to standard methods, particularly at the presence of differing noise levels. The approach is also applied on quantifying emphysema on a large data set of cardiac CT scans, and is shown to improve the prediction of emphysema extent on subsequent full-lung CT scans. The second major contribution of this work applies unsupervised learning to recognizing patterns of emphysema on CT. Instead of trying to reproduce the classic subtypes, the novel approach aims to capture the most dominant variations of lung structure pertaining to emphysema. While removing the reliance on visually assigned labels, the learned patterns are shown to represent different manifestations of emphysema with distinct appearances and regular spatial distributions. The clinical significance of the patterns is also demonstrated, along with high-level performance in the application of content-based image retrieval. The contributions of this work advance the analysis of emphysema on CT by applying novel machine learning approaches to increase the value of the available imaging data. Probabilistic methods improve from the crude standard methods that are currently used to quantitate emphysema, and the value of learning disease patterns directly from image data is demonstrated. The common framework relying on replicating visually assigned labels of outdated subtypes has not achieved widespread acceptance. The methodology presented in this work may have a substantial impact on how emphysema subtypes on CT are recognized and defined in the future.
345

Avaliação da morfologia interna de sementes de citrumelo \'Swingle\' por meio de raios X / Evaluation of the internal morphology of \'Swingle\' citrumelo seeds by of X-ray

Arruda, Natália 16 February 2017 (has links)
O teste de raios X é um teste rápido, simples, não destrutivo e de alta precisão, que possibilita examinar com detalhes, a morfologia interna da semente, identificar áreas danificadas, sua localização e tipos de danos. Uma das abordagens atuais da pesquisa sobre análise de imagens de sementes radiografadas é verificar até que ponto a relação entre o grau de desenvolvimento embrionário e o espaço disponível na cavidade interna da semente está associada ao desempenho da semente. Na literatura há diversos trabalhos com resultados promissores para diferentes espécies; porém, para sementes de citros são escassas estas informações. Neste sentido, os objetivos desta pesquisa foram: a) avaliar a eficiência do teste de raios X em relacionar a morfologia interna das sementes com a germinação das sementes de citrumelo \'Swingle\'; b) verificar a possibilidade de utilização do teste de raios X para avaliar a poliembrionia das sementes de citrumelo \'Swingle\'; c) verificar se há relação do espaço livre na cavidade interna com o desempenho das sementes de citrumelo \'Swingle\'. Foram utilizados sete lotes de sementes tratadas de citrumelo \'Swingle\'. A pesquisa foi dividida em três experimentos: experimento I - avaliação da morfologia interna das sementes de por meio de raios X; experimento II - avaliação da poliembrionia das sementes por meio do teste de raios X; experimento III - avaliação do potencial fisiológico das sementes por meio dos testes tradicionais de vigor e avaliação do espaço livre da cavidade interna das sementes por meio do software ImageJ. O primeiro e o segundo experimento foram conduzidos em uma época de avaliação, porém, o terceiro experimento foi conduzido em duas épocas, espaçada em oito meses de armazenamento (0 e 8 meses), durante esse período as sementes foram armazenadas em câmara fria com a temperatura de 5°C e umidade relativa do ar de 75 %. O teste de raios X foi realizado nos três experimentos e relacionado com a germinação, porém no experimento II foi relacionado também com o metódo direto (contagem dos embriões) e no experimento III as imagens radiográficas foram analisadas por meio do software ImageJ para determinar o espaço livre das sementes. Para determinar o potencial fisiológico, os lotes de sementes foram submetidos a testes de germinação e de vigor (primeira contagem de germinação, velocidade de germinação, tempo médio de germinação, emergência de plântulas em areia, comprimento e massa de matéria seca da parte aérea e raiz de plântulas), foi avaliado também número médio de plântulas por sementes e a taxa de poliembrionia de cada lote. Verificou-se que a análise de imagens de raios X permite indentificar danos internos na semente com efeitos negativos na germinação; é um método eficiente para avaliar a poliembrionia das sementes; e a alta porcentagem de sementes com espaço livre interno superior a 22,1% prejudica o potencial germinativo de sementes de citrumelo \'Swingle\'. / X-ray test is a fast, simple, non-destructive, high-precision test that allows you to examine in detail the internal morphology of the seed, identify damaged areas, their location and types of damage. One of the current approaches to X-ray seed imaging research is to ascertain the extent to which the relationship between the degree of embryonic development and the available space in the internal cavity of the seeds is associated with seed performance. In the literature there are several works with promising results for different species; however, this information is scarce for citrus seeds. In this sense, the objectives of this research were: a) to evaluate the efficiency of the X-ray test in relation to the internal morphology of the seeds with the germination of \'Swingle\' citrumelo seeds; b) to verify the possibility of using the X-ray test to evaluate the polyembryony of the \'Swingle\' citrumelo seeds; c) to verify if there is a relation of free space in the internal cavity with the performance of \'Swingle\' citrumelo seeds. Seven lots of treated \'Swingle\' citrumelo seeds were used, the research was divided into three experiments: experiment I - evaluation of the internal morphology of seeds by X-ray; experiment II - evaluation of seed polyembryony by X-ray test; experiment III - evaluation of the physiological potential of the seeds by traditional tests of vigor and evaluation of the free space of the internal cavity of the seeds by of ImageJ software. The first and second experiments were conducted at a time of evaluation, but the third experiment was conducted in two seasons, spaced in eight months of storage (0 and 8 months), during which time the seeds were stored cold chamber with temperature of 5 °C and relative humidity of 75 %. The X-ray test was performed in the three experiments and related to germination, but in experiment II it was also related to the direct method (counting of the embryos) and in experiment III the radiographic images were analyzed by of the ImageJ software to determine the space of the seeds. In order to determine the physiological potential, seed lots were submitted to germination and vigor tests (first germination count, speed of germination, mean time germination, emergence of seedlings in sand, length and dry mass of aerial part and root of seedlings), we also evaluated the average number of seedlings per seed and the polyembryony rate of each lot. It was verified that X-ray image analysis allows identification of internal damage in the seed with negative effects on germination; is an efficient method to evaluate the polyembryony of the seeds; and the high percentage of seeds with internal free space greater than 22.1% impairs the germination potential of \'Swingle\' citrumelo seeds.
346

Aplicação da Transformada de Hough para localização dos olhos em faces humanas / not available

Marroni, Lilian Saldanha 27 August 2002 (has links)
Com a crescente necessidade de segurança, o processo de identificação pessoal é cada vez mais exigido. A extração de características faciais é um passo importante quando se lida com interpretação visual automatizada no reconhecimento de faces humanas. Dentre as características faciais, os olhos são partes importantes no processo de reconhecimento, pois determinam o início da busca por outras características relevantes. Neste trabalho é apresentado um método de localização de olhos em imagens frontais de faces humanas. Este método é subdividido em duas partes. Primeiro, são identificados os possíveis candidatos a olhos usando a Transformada de Hough para círculos; depois é aplicada a Distância Euclidiana confirmando-se a localização pro biometria facial. / Personal identification process is an exigency for security systems. Facial feature extraction is a crucial step for automated visual interpretation in human face recognition. Withim all the facial features, the eyes are significantly parts for the recognition process, therefore they set up the start for another relevant feature search. In this work, we present a method for eyes locating in digital images of frontal human faces. This method is subdivided into two parts. First, we identify the possible eyes\'s candidates by Hough Transfor for circules, them we apply the Euclidian distance and calculate the eyes\'s position by facial biometric measurement.
347

Markov random fields based image and video processing. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2010 (has links)
In this dissertation, we propose three methods to solve the problems of interactive image segmentation, video completion, and image denoising, which are all formulated as MRF-based energy minimization problems. In our algorithms, different MRF-based energy functions with particular techniques according to the characteristics of different tasks are designed to well fit the problems. With the energy functions, different optimization schemes are proposed to find the optimal results in these applications. In interactive image segmentation, an iterative optimization based framework is proposed, where in each iteration an MRF-based energy function incorporating an estimated initial probabilistic map of the image is optimized with a relaxed global optimal solution. In video completion, a well-defined MRF energy function involving both spatial and temporal coherence relationship is constructed based on the local motions calculated in the first step of the algorithm. A hierarchical belief propagation optimization scheme is proposed to efficiently solve the problem. In image denoising, label relaxation based optimization on a Gaussian MRF energy is used to achieve the global optimal closed form solution. / Many problems in computer vision involve assigning each pixel a label, which represents some spatially varying quantity such as image intensity in image denoising or object index label in image segmentation. In general, such quantities in image processing tend to be spatially piecewise smooth, since they vary smoothly in the object surface and change dramatically at object boundaries, while in video processing, additional temporal smoothness is satisfied as the corresponding pixels in different frames should have similar labels. Markov random field (MRF) models provide a robust and unified framework for many image and video applications. The framework can be elegantly expressed as an MRF-based energy minimization problem, where two penalty terms are defined with different forms. Many approaches have been proposed to solve the MRF-based energy optimization problem, such as simulated annealing, iterated conditional modes, graph cuts, and belief propagation. / Promising results obtained by the proposed algorithms, with both quantitative and qualitative comparisons to the state-of-the-art methods, demonstrate the effectiveness of our algorithms in these image and video processing applications. / Liu, Ming. / Adviser: Xiaoou Tang. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 79-89). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
348

Territorializações online : o Cais do Mauá em imagens no ciberespaço

Ripoll, André Cavedon January 2016 (has links)
O ciberespaço é tratado por alguns autores como um dos vetores de desterritorialização, problemática que assume importância nas ciências que tratam do espaço na modernidade tardia. Por um lado, por provocar uma evasão da materialidade; por outro, em uma perspectiva que interessa mais a este trabalho, por se configurar como um ambiente de enunciações mais livres do que as possíveis antes de seu advento, rompendo com discursos totalizantes acerca do espaço. Este trabalho examina como a cidade pode se construir em discursos no ambiente online. Estes discursos são tomados como territorializações, sucessão de linhas de des/reterritorialização que constituem um dizer território, e nestas construções, assim como na construção da cidade material, operam agentes táticos e estratégicos. Interessam em particular os discursos na forma imagética. Estes são entendidos como agenciamentos de diversos discursos e têm seu sentido produzido em uma relação dialógica com o contexto de enunciação. A dissertação apresenta um estudo de caso da construção discursiva em imagens do projeto Cais Mauá, em Porto Alegre, no site de relacionamentos Facebook. A pesquisa examinou doze imagens postadas em dois agrupamentos na plataforma. Para a coleta destas imagens, foi utilizada a ferramenta Netvizz. Para a análise destas imagens foi construído um método que incorporou descritores formais e icônicos das imagens a elementos de análise de discurso da hermenêutica dialógica. Com este método, se construiu o signo Cais Mauá para cada um dos agrupamentos e posteriormente o signo Cais Mauá que se produz na relação dialógica entre os dois agrupamentos. O trabalho contribui para a metodologia de análise visual e para a compreensão da cidade no contexto contemporâneo de aumento das relações mediadas pelo computador. / Some authors have held ciberspace as a vector of deterritorialization, a problem that has risen in importance in late modernity among sciences that deal with space. On the one hand because ciberspace incurs in an evasion of materiality; on the other hand, more relevant to this work, because it presents a space capable of more free enunciation than it was possible before its advent, rupturing with totalizing discourses about space. This work examines how the city can be constructed in discourses in this online environment. These discourses are held as territorializations, successions of de/reterritorializations that constitute a speech on territory. In these constructions, as in the construction of the material city, both strategic and tactical agents operate. Discourses in the form of images are particularly relevant. Held as collective agencies, their meaning is produced from the dialogical relation to the context of enunciation. This dissertation presents a case study on the imagetic discoursive construction of the Cais Mauá project, in Porto Alegre, on Facebook, a social media platform. The research analyzed twelve imagens posted to two groupings on the website. For data collection, the Netvizz tool was used. A method was built for the analysis of these images, to which formal and iconic descriptors were incorporated, as well as elements of dialogic hermeneutics, a method of discourse analysis. By this method, the sign Cais Mauá was constructed according to each of the groupings and later according to the dialogical relationship between the two groupings. This work contributes to visual analysis methodology and to the understanding of the city in a contemporary context of computer-mediated relationships.
349

Generic signboard detection in image and video.

January 2003 (has links)
by Shen Hua. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 67-71). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgments --- p.v / Table of Contents --- p.vii / List of Figures --- p.ix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Object Detection --- p.2 / Chapter 1.2 --- Signboard Detection --- p.3 / Chapter Chapter 2 --- System Overview --- p.5 / Chapter 2.1 --- What is the problem? --- p.5 / Chapter 2.2 --- Review of previous work --- p.6 / Chapter 2.3 --- System Outline --- p.8 / Chapter Chapter 3 --- Preprocessing --- p.10 / Chapter 3.1 --- Edge Detection --- p.11 / Chapter 3.1.1 --- Gradient-Based Method --- p.11 / Chapter 3.1.2 --- Laplacian of Gaussian --- p.14 / Chapter 3.1.3 --- Canny edge detection --- p.15 / Chapter 3.2 --- Corner Detection --- p.18 / Chapter Chapter 4 --- Finding Candidate Lines --- p.22 / Chapter 4.1 --- Hough Transform --- p.22 / Chapter 4.1.1 --- What is Hough Transform --- p.22 / Chapter 4.1.2 --- Parameter Space --- p.22 / Chapter 4.1.3 --- Accumulator Array --- p.24 / Chapter 4.2 --- Gradient-based Hough Transform --- p.25 / Chapter 4.2.1 --- Direction of Gradient --- p.26 / Chapter 4.2.2 --- Accumulator Array --- p.28 / Chapter 4.2.3 --- Peaks in the accumulator array --- p.30 / Chapter 4.2.4 --- Performance of Gradient-based Hough Transform --- p.32 / Chapter Chapter 5 --- Signboards Locating --- p.35 / Chapter 5.1 --- Line Verification --- p.35 / Chapter 5.1.1 --- Line Segmentation --- p.35 / Chapter 5.1.2 --- Density Checking --- p.37 / Chapter 5.2 --- Finding Close Circuits --- p.40 / Chapter 5.3 --- Remove Redundant Segments --- p.47 / Chapter Chapter 6 --- Post processing --- p.54 / Chapter Chapter 7 --- Experiments and Conclusion --- p.59 / Chapter 7.1 --- Experimental Results --- p.59 / Chapter 7.2 --- Conclusion --- p.66 / Bibliography --- p.67
350

Relações de gênero na imprensa esportiva / Gender relations in the sports press

Erik Giuseppe Barbosa Pereira 08 July 2015 (has links)
O objetivo deste documento é apresentar os artigos que compõem a tese, cuja abordagem temática circunscreve-se sobre as relações de gênero na imprensa esportiva. Em nível de organização, sentimo-nos à vontade para dividirmos esta tese em dois blocos: o de BASE e o de APROFUNDAMENTO. O Bloco base é composto pelos artigos "Os estudos de gênero e masculinidade e seus reflexos para a Educação Física" e "O olhar da imprensa sobre o vôlei feminino: quando a sombra se destaca". O Primeiro versa sobre uma reflexão sobre as identidades e os desdobramentos das masculinidades para a área da Educação Física e esportes. Nessa empreitada, pudemos inferir que os estudos sobre as temáticas Gênero e Masculinidades apontam-nos para um terreno fecundo e promissor no que diz respeito à contemporaneidade e a abrangência teórica no universo da ciência com a qual esta área de saber dialoga. Destarte, somos levados a inferir que os esportes, ao que tudo indica, vem atuando como legitimadora e reprodutora de uma ideologia hegemônica, sexista, patriarcal e machista. O segundo artigo, abordamos a história da inserção e da permanência das mulheres no universo dos esportes, utilizando a técnica da análise de imagens. Verificamos que a imprensa esportiva ainda carreia a imagem das mulheres atletas mantendo padrões ainda subordinados a uma hegemonia masculina que legisla sobre o que se quer ver. Já no segundo bloco, é composto pelos estudos "Jogos Olímpicos de Londres 2012: brasileiros e brasileiras em foco" e "Revelações dos fotógrafos esportivos brasileiros sobre relações de gênero". No primeiro estudo, ao analisarmos as imagens publicadas em jornais no período olímpico de 2012, percebemos que é evidente a quantidade e dimensão superior das imagens masculinas frente às femininas. Também, nas poucas vezes em que o homem é retratado denotando emotividade, choro ou decepção, as imagens divulgadas são de dimensões médias ou pequenas. E nas raras vezes em que a mulher é registrada durante a execução de gestos técnicos, vale-se do mesmo ocorrido no masculino: fotos médias ou pequenas e restritas ao interior do jornal. No artigo seguinte desse bloco, constatamos que o discurso dos fotógrafos para clicar atletas seguem as premissas: focam o corpo feminino belo e sensual em detrimento da representação de seu movimento no esporte, o que explica a apresentação de conotação sexual; sua performance é relegada a segundo plano. Já o corpo masculino, quando exposto sugerindo algum tipo de apelo, é representado de forma diferenciada, não vexatória ou pejorativa e sempre em posição de altivez. Verificamos que o publicado nos jornais não condiz com os discursos proferidos pelos entrevistados, uma vez que em diversos momentos afirmaram não haver discrepâncias quanto ao registro do masculino e do feminino. Nas Considerações finais, elencamos as principais impressões da composição da obra. Nesse item, pudemos confirmar que atletas masculinos e femininos têm tratamentos diferenciados e desiguais nos discursos e nas imagens exibidas pela imprensa esportiva. / The objective of this document is to present the articles that form this thesis, which has a thematic approach based on gender relations in sports press. On an organizational level, this thesis can be divided into two blocks, the basic information and the details. The basic information block contains two articles: "The studies of gender and masculinity and the consequences for Physical Education" and "The eye of the press on female volleyball: when the shadows call attention to themselves". The first is on identities and the effects of masculinity on the Physical Education and Sports area. In the context of this article, it is possible to infer that studies about "gender" and "masculinity" themes are fertile and promising terrain regarding the contemporaneity and theory in the scientific universe that is touched by this area of knowledge. As such, one can infer that sports have been legitimizing and reproducing an hegemonic ideology that is sexist, male chauvinist and patriarchal. In the second article, the history of female insertion and permanence in the world of sports was analyzed through an image analysis technique. The investigation found that the image of female athletes is still being divulged by the sporting press under a male hegemony, that "legislates" about what it wants to see. The second block of articles is composed by two other articles, as follows: "London 2012 Olympic Games: male and female Brazilians in focus." and "Revelations of Brazilian sporting photographers about gender relations.". In the first study, through the analysis of female athlete images published in newspapers during the Olympic Games, it was determined that there was a greater number of male athlete images and that when men were depicted in a moment of weakness, the image was smaller, whereas women, when shown executing technical gestures, were also relegated to smaller spaces than men in the same situation. In the second article of this block, results show that sports photographers have a specific set of considerations when photographing athletes: when depicting female athletes, they focus on beautiful and sensual female bodies, with little room for representations of their movements in sport, so there is a primarily sexual connotation and their sports performance is relegated to the background. Male athletes, however, when represented in any way that may suggest appeal, are shown differently, in a form that is neither pejorative nor vexing, and always in a manner that conveys pride. The investigation determined that what is published in the newspapers is different from what the photographers stated, considering that many times they affirmed that there was no difference between male and female athletes in sports photography. In the "Final Considerations" section, all of the main impressions brought on by the investigation were recorded. As it is, male and female athletes are treated differently and unequally in the discourse and images exhibited by the sporting press.

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