Global ETD Search

121	Métodos numéricos para o retoque digital / Santos, Claudia Augusta dos. January 2005 (has links) Orientador: Maurílio Boaventura / Banca: Antonio Castelo Filho / Banca: Heloisa Helena Marino Silva / Resumo: O objetivo deste trabalho þe aplicar Mþetodos Numþericos de ordem de precisão mais alta ao problema de Retoque Digital, visando melhorar a qualidade da aproximação quando comparada com o Método de Euler, que þe geralmente utilizado para esse tipo de problema. Para testar a eficiência de tais métodos, utilizamos três modelos de Retoque Digital: o modelo proposto por Bertalmþýo, Sapiro, Ballester e Caselles (BSBC), o modelo de Rudin, Osher e Fatemi conhecido como Variacional Total (TV) e o modelo de Chan e Shen, chamado de Difusão Guiada pela Curvatura (CDD). / Abstract: The purpose of this work is to apply Numerical Methods of higher order to the problem of Digital Inpainting, aiming to improve the quality of the approach when compared with the Eulers Method which is generally used for this kind of problem. To test the e ciency of these methods we use three models of Digital Inpainting: the model considered by Bertalmþýo, Sapiro, Ballester and Caselles (BSBC), the model of Rudin, Osher and Fatemi known as Total Variation (TV) and the model of Chan and Shen, named Curvature Driven Di usion (CDD) / Mestre Matemática aplicada. Digital inpainting. eng Predictor-corrector method. eng Linear multistep methods. eng Eulers method. eng Finite Diferences. eng Processing of digital images. eng Numerical methods. eng
122	Um método espectrométrico de emissão em chama baseado em imagens digitais para determinação indireta de fármacos e determinação simultânea de sódio e cálcio / A Digital Image-Based Flame Emission Spectrometric Method for Indirect Determination of Drugs and Simultaneous Determination of Sodium and Calcium Lyra, Wellington da Silva 11 September 2012 (has links) Made available in DSpace on 2015-05-14T13:21:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 12264651 bytes, checksum: c1dad0a27d50ddb05acdcc8e21042b61 (MD5) Previous issue date: 2012-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work the potential of the Digital Image-Based Flame Emission Spectrometry (DIB-FES) is demonstrated through two completely separate applications. The first one consists in the indirect determination of three drugs in injectable form: sodium dicofenac, sodium dipyrone and clacium gluconate and the second in the combination of DIB-FES with Multiple Linear Regression (MLR) for the simultaneous determination of sodium and calcium in powder milk. Up to the present moment the literature does not report the use of traditional FES in: indirect determination of organic substances, simultaneous determination of analytes using a unique detector and overcoming the problem of spectral interference. In DIB-FES digital images of the flame are captured by webcam in its oxidant region (2,5 cm over the burner of the flame photometer) and are associated with the radiation emitted by metals present in the air-butane flame. Based on Red-Green-Blue (RGB) colour system, univariate and multivariate calibration models were developed, which were validated and then applied to real samples. In each application the results were compared with the results obtained by their respective reference methods. There were no statistically significant differences between the results when the paired t-test at the 95% confidence level. The estimated precision was better than the respective reference methods and accuracy was assessed by high values of bias and recovery rates between 97 and 104% in the two applications. / Neste trabalho a potencialidade da Espectrometria de Emissão em Chama Baseada em Imagens digitais (DIB-FES) é demonstrada por meio de duas aplicações completamente distintas. A primeira consiste na determinação indireta de três fármacos em soluções injetáveis: diclofenaco sódico, dipirona sódica e gluconato de cálcio e a segunda na combinação da DIB-FES com Regressão Linear Múltipla (MLR) para a determinação simultânea de sódio e cálcio em amostras de leite em pó. Até o presente momento a literatura não reporta a utilização da FES tradicional na: determinação indireta de substâncias orgânicas, determinação simultânea de analitos utilizando um único detector e superação do problema de interferência espectral. Na DIB-FES as imagens digitais da chama são capturadas pela webcam na região oxidante da mesma (2,5 cm acima do queimador do fotômetro) e estão associadas às radiações emitidas pelos metais presentes na chama ar-butano. Com base no sistema de cores Vermelho-Verde-Azul (RGB) foram desenvolvidos modelos de calibração univariada e multivariada, os quais foram validados e então aplicados em amostras reais. Em cada aplicação os resultados obtidos foram comparados com os resultados obtidos por seus respectivos métodos de referência. Não houve diferenças estatisticamente significativas entre resultados ao aplicar o teste t emparelhado ao nível de 95% de confiança. A precisão estimada foi melhor do que a de seus respectivos métodos de referência e a exatidão foi verificada por altas taxas de tendência e fatores de recuperação entre 97 e 104% nas duas aplicações. Imagens digitais Sistema de cores RGB Injetáveis e Leite em pó Digital images RGB colour system Injection drugs and Powder milk CIENCIAS EXATAS E DA TERRA::QUIMICA
123	Uso de imagens digitais para determinação quantitativa de metanol em bebidas alcoólicas Reis, Josiane Amorim, 92-99125-7184 31 July 2017 (has links) Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-08T13:43:05Z No. of bitstreams: 2 Dissertação_Josiane A. Reis.pdf: 2107398 bytes, checksum: 8227d0b419e79cd9673a8f0c0f25f611 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-08T13:43:17Z (GMT) No. of bitstreams: 2 Dissertação_Josiane A. Reis.pdf: 2107398 bytes, checksum: 8227d0b419e79cd9673a8f0c0f25f611 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-08T13:43:17Z (GMT). No. of bitstreams: 2 Dissertação_Josiane A. Reis.pdf: 2107398 bytes, checksum: 8227d0b419e79cd9673a8f0c0f25f611 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-07-31 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Concerned about sustainability, analytical chemists have developed chemical analysis procedures that aim to minimize the consumption of reagents and samples combined with the reduction of operating costs. Thus, in recent years, Digital Image Based (DIB) methods have often been used as an alternative to quantitative determinations in analytical chemistry, especially in samples of environmental interest, food, beverages and drugs. This work proposes a method based on digital images for the determination of methanol in alcoholic beverages. The proposed system uses a scanner to acquire images generated according to the RGB (Red, Green, Blue) system. The determination of methanol is based on an oxidation reaction of methanol. After the reaction an image is captured and a region of the image is selected for decomposition of the pixels into the values of the RGB components. The analytical curve is obtained by relating the logarithm of the ratio between the white solution standard and the norm of the calibration solutions as a function of the concentrations of these solutions. The methanol content was determined in (mL / 100 mL of anhydrous alcohol) in the samples of cachaça, brandy and liqueur of jambú, cupuaçu and cocoa. In order to illustrate the viability of the proposed method, analyzes were performed on seven beverage samples. The results were compared with those obtained by spectrophotometry and when applying the paired t-test it was found that there was no statistically significant difference between the results obtained with the two methods at a 95% confidence level. / Preocupados com a sustentabilidade os químicos analíticos têm desenvolvido procedimentos de análise química que visam minimizar o consumo de reagentes e amostras aliadas a redução de custos operacionais. Dessa forma, nos últimos anos os métodos Baseados em Imagens Digitais (DIB) têm sido frequentemente usados como uma alternativa para determinações quantitativas em química analítica, principalmente em amostras de interesse ambiental, alimentícios, bebidas e fármacos. Neste trabalho propõe se um método baseado em imagens digitais para determinação de metanol em bebidas alcoólicas. O sistema proposto usa um scanner para aquisição das imagens geradas de acordo com o sistema RGB (Red, Green, Blue). A determinação do metanol é baseada em uma reação de oxidação do metanol. Após a reação uma imagem é capturada e uma região da imagem é selecionada para decomposição dos pixels nos valores das componentes RGB. A curva analítica é obtida relacionando o logaritmo da razão entre a norma da solução do branco e a norma das soluções de calibração em função das concentrações dessas soluções. O teor de metanol foi determinado em (mL/ 100mL de álcool anidro) nas amostras de cachaça, aguardente, licor de jambú, cupuaçu e cacau. A fim de ilustrar a viabilidade do método proposto, foram realizadas analises em sete amostras de bebidas. Os resultados foram comparados com os obtidos por espectrofotometria e ao se aplicar o teste t emparelhado verificou-se que não há estatisticamente diferença significativa entre os resultados obtidos com os dois métodos para um nível de 95% de confiança. Metanol em bebidas Scanner na química Componentes RGB (Red, Green, Blue) Imagens digitais Método do ácido cromotrópico Espectrofotômetria Methanol in beverages Digital images Scanner in chemistry Chromotropic acid method Spectrophotometry CIÊNCIAS AGRÁRIAS
124	Natural scene classification, annotation and retrieval. Developing different approaches for semantic scene modelling based on Bag of Visual Words. Alqasrawi, Yousef T. N. January 2012 (has links) With the availability of inexpensive hardware and software, digital imaging has become an important medium of communication in our daily lives. A huge amount of digital images are being collected and become available through the internet and stored in various fields such as personal image collections, medical imaging, digital arts etc. Therefore, it is important to make sure that images are stored, searched and accessed in an efficient manner. The use of bag of visual words (BOW) model for modelling images based on local invariant features computed at interest point locations has become a standard choice for many computer vision tasks. Based on this promising model, this thesis investigates three main problems: natural scene classification, annotation and retrieval. Given an image, the task is to design a system that can determine to which class that image belongs to (classification), what semantic concepts it contain (annotation) and what images are most similar to (retrieval). This thesis contributes to scene classification by proposing a weighting approach, named keypoints density-based weighting method (KDW), to control the fusion of colour information and bag of visual words on spatial pyramid layout in a unified framework. Different configurations of BOW, integrated visual vocabularies and multiple image descriptors are investigated and analyzed. The proposed approaches are extensively evaluated over three well-known scene classification datasets with 6, 8 and 15 scene categories using 10-fold cross validation. The second contribution in this thesis, the scene annotation task, is to explore whether the integrated visual vocabularies generated for scene classification can be used to model the local semantic information of natural scenes. In this direction, image annotation is considered as a classification problem where images are partitioned into 10x10 fixed grid and each block, represented by BOW and different image descriptors, is classified into one of predefined semantic classes. An image is then represented by counting the percentage of every semantic concept detected in the image. Experimental results on 6 scene categories demonstrate the effectiveness of the proposed approach. Finally, this thesis further explores, with an extensive experimental work, the use of different configurations of the BOW for natural scene retrieval. / Applied Science University in Jordan Image classification Image retrieval Bag of visual words Visual vocabulary Features fusion Spatial pyramid layout Concept-based bag of visual words Digital images Natural scene classification
125	Signal Processing Algorithms For Digital Image Forensics Prasad, S 02 1900 (has links) Availability of digital cameras in various forms and user-friendly image editing softwares has enabled people to create and manipulate digital images easily. While image editing can be used for enhancing the quality of the images, it can also be used to tamper the images for malicious purposes. In this context, it is important to question the originality of digital images. Digital image forensics deals with the development of algorithms and systems to detect tampering in digital images. This thesis presents some simple algorithms which can be used to detect tampering in digital images. Out of the various kinds of image forgeries possible, the discussion is restricted to photo compositing (Photo montaging) and copy-paste forgeries. While creating photomontage, it is very likely that one of the images needs to be resampled and hence there will be an inconsistency in some of its underlying characteristics. So, detection of resampling in an image will give a clue to decide whether the image is tampered or not. Two pixel domain techniques to detect resampling have been presented. The rest of them exploits the property of periodic zeros that occur in the second divergences due to interpolation during resembling. It requires a special condition on the resembling factor to be met. The second technique is based on the periodic zero-crossings that occur in the second divergences, which does not require any special condition on the resembling factor. It has been noted that this is an important property of revamping and hence the decay of this technique against mild counter attacks such as JPEG compression and additive noise has been studied. This property has been repeatedly used throughout this thesis. It is a well known fact that interpolation is essentially low-pass filtering. In case of photomontage image which consists of resample and non resample portions, there will be an in consistency in the high-frequency content of the image. This can be demonstrated by a simple high-pass filtering of the image. This fact has also been exploited to detect photomontaging. One approach involves performing block wise DCT and reconstructing the image using only a few high-frequency coercions. Another elegant approach is to decompose the image using wavelets and reconstruct the image using only the diagonal detail coefficients. In both the cases mere visual inspection will reveal the forgery. The second part of the thesis is related to tamper detection in colour filter array (CFA) interpolated images. Digital cameras employ Bayer filters to efficiently capture the RGB components of an image. The output of Bayer filter are sub-sampled versions of R, G and B components and they are completed by using demosaicing algorithms. It has been shown that demos icing of the color components is equivalent to resembling the image by a factor of two. Hence, CFA interpolated images contain periodic zero-crossings in its second differences. Experimental demonstration of the presence of periodic zero-crossings in images captured using four digital cameras of deferent brands has been done. When such an image is tampered, these periodic zero-crossings are destroyed and hence the tampering can be detected. The utility of zero-crossings in detecting various kinds of forgeries on CFA interpolated images has been discussed. The next part of the thesis is a technique to detect copy-paste forgery in images. Generally, while an object or a portion if an image has to be erased from an image, the easiest way to do it is to copy a portion of background from the same image and paste it over the object. In such a case, there are two pixel wise identical regions in the same image, which when detected can serve as a clue of tampering. The use of Scale-Invariant-Feature-Transform (SIFT) in detecting this kind of forgery has been studied. Also certain modifications that can to be done to the image in order to get the SIFT working effectively has been proposed. Throughout the thesis, the importance of human intervention in making the final decision about the authenticity of an image has been highlighted and it has been concluded that the techniques presented in the thesis can effectively help the decision making process. Digital Image Forgery Photomontage Forgery Copy-Paste Forgery Images - Resampling Detection Digital Images - Tampering - Algorithms Interpolated Images - Tamper Detection Digital Image Forensics Image Forgery Detection Colour Filter Array (CFA) Scale-Invariant-Feature-Transform (SIFT) Electrical Engineering
126	As janelas de David Hockney: os dispositivos móveis no processo de criação artística / The windows of David Hockney: mobile devices in the process of artistic creation Jokowiski, Graciela Johnsson Campos 24 March 2017 (has links) Esta dissertação apresenta uma abordagem sobre os dispositivos móveis como possíveis mediadores do pensamento artístico. Fundamentada em conceitos teóricos que permeiam as relações entre arte, imagem e tecnologia, pretende compreender a participação destes dispositivos no processo de criação a partir da observação da arte visual de David Hockney nos celulares e tablets. Seus objetivos específicos abrangem estudos de como os artistas da arte contemporânea têm se expressado por meio das imagens e como as janelas digitais têm participado deste movimento. A dissertação se inicia com um estudo teórico sobre as janelas da arte, priorizando aquelas que se inserem na arte contemporânea, seguida por uma investigação da trajetória do artista David Hockney. A pesquisa teórica foi importante para o entendimento de como as artes visuais contemporâneas têm materializado os conceitos dos artistas. A arte de Hockney nos dispositivos móveis é analisada a partir da exposição da série de pinturas Flores Frescas, onde o artista expõe suas obras nos tablets e celulares. A análise das imagens de Hockney complementa a pesquisa por meio de uma observação qualitativa e interpretativa de seis obras da mesma série, fundamentada em parâmetros que a pesquisa teórica indicou como prioritários para a construção de uma estética da arte digital. Esta análise identificou tendências da criação artística incorporadas nas pinturas a partir dos dispositivos móveis. A conclusão mostra uma apropriação do dispositivo por este artista por meio de um processo criativo que colabora para a formação de uma estética contemporânea. / This research presents an approach on mobile devices as possible mediators of artistic thinking. Based on theoretical concepts about the relations between art, image and technology, it aims at understanding the participation of these devices in the process of creation from the observation of the visual art of David Hockney in the cellular phones and tablets. Its specific objectives are the studies of how artists of contemporary art have expressed themselves through images and how digital windows have participated in this movement. The research paper begins with a theoretical study on metaphorical windows in art, prioritizing those of contemporary art, and continues an investigation into the trajectory of the artist David Hockney. Theoretical research was important for the understanding of how visual arts materialize the concepts of contemporary artists. Hockney's art on mobile devices is analyzed from the Fresh Flowers painting exposition, in which the artist exposes his works on tablets and cell phones. The analysis of Hockney’s images complements the research through the observation of six paintings of the same series, based on parameters that the theoretical research indicated as important for the construction of an aesthetic of digital art. This analysis was important in identifying trends in artistic creation embodied in paintings for mobile devices. The conclusion shows an appropriation of the device by this artist through a painting that contributes to the formation of a contemporary aesthetic. CNPQ::LINGUISTICA, LETRAS E ARTES::ARTES Hockney, David, 1937 - Exposições Criação na arte Dispositivos móveis Arte e tecnologia Arte moderna Mediação Imagens digitais Arte digital Tecnologia Hockney, David, 1937 - Exposições Creation in art mobile devices Art and technology Art, Modern Computer art Mediation Digital images Technology Sociais e Humanidades
127	As janelas de David Hockney: os dispositivos móveis no processo de criação artística / The windows of David Hockney: mobile devices in the process of artistic creation Jokowiski, Graciela Johnsson Campos 24 March 2017 (has links) Esta dissertação apresenta uma abordagem sobre os dispositivos móveis como possíveis mediadores do pensamento artístico. Fundamentada em conceitos teóricos que permeiam as relações entre arte, imagem e tecnologia, pretende compreender a participação destes dispositivos no processo de criação a partir da observação da arte visual de David Hockney nos celulares e tablets. Seus objetivos específicos abrangem estudos de como os artistas da arte contemporânea têm se expressado por meio das imagens e como as janelas digitais têm participado deste movimento. A dissertação se inicia com um estudo teórico sobre as janelas da arte, priorizando aquelas que se inserem na arte contemporânea, seguida por uma investigação da trajetória do artista David Hockney. A pesquisa teórica foi importante para o entendimento de como as artes visuais contemporâneas têm materializado os conceitos dos artistas. A arte de Hockney nos dispositivos móveis é analisada a partir da exposição da série de pinturas Flores Frescas, onde o artista expõe suas obras nos tablets e celulares. A análise das imagens de Hockney complementa a pesquisa por meio de uma observação qualitativa e interpretativa de seis obras da mesma série, fundamentada em parâmetros que a pesquisa teórica indicou como prioritários para a construção de uma estética da arte digital. Esta análise identificou tendências da criação artística incorporadas nas pinturas a partir dos dispositivos móveis. A conclusão mostra uma apropriação do dispositivo por este artista por meio de um processo criativo que colabora para a formação de uma estética contemporânea. / This research presents an approach on mobile devices as possible mediators of artistic thinking. Based on theoretical concepts about the relations between art, image and technology, it aims at understanding the participation of these devices in the process of creation from the observation of the visual art of David Hockney in the cellular phones and tablets. Its specific objectives are the studies of how artists of contemporary art have expressed themselves through images and how digital windows have participated in this movement. The research paper begins with a theoretical study on metaphorical windows in art, prioritizing those of contemporary art, and continues an investigation into the trajectory of the artist David Hockney. Theoretical research was important for the understanding of how visual arts materialize the concepts of contemporary artists. Hockney's art on mobile devices is analyzed from the Fresh Flowers painting exposition, in which the artist exposes his works on tablets and cell phones. The analysis of Hockney’s images complements the research through the observation of six paintings of the same series, based on parameters that the theoretical research indicated as important for the construction of an aesthetic of digital art. This analysis was important in identifying trends in artistic creation embodied in paintings for mobile devices. The conclusion shows an appropriation of the device by this artist through a painting that contributes to the formation of a contemporary aesthetic. CNPQ::LINGUISTICA, LETRAS E ARTES::ARTES Hockney, David, 1937 - Exposições Criação na arte Dispositivos móveis Arte e tecnologia Arte moderna Mediação Imagens digitais Arte digital Tecnologia Hockney, David, 1937 - Exposições Creation in art mobile devices Art and technology Art, Modern Computer art Mediation Digital images Technology Sociais e Humanidades
128	Structural priors for multiobject semi-automatic segmentation of three-dimensional medical images via clustering and graph cut algorithms / A priori de structure pour la segmentation multi-objet d'images médicales 3d par partition d'images et coupure de graphes Kéchichian, Razmig 02 July 2013 (has links) Nous développons une méthode générique semi-automatique multi-objet de segmentation d'image par coupure de graphe visant les usages médicaux de routine, allant des tâches impliquant quelques objets dans des images 2D, à quelques dizaines dans celles 3D quasi corps entier. La formulation souple de la méthode permet son adaptation simple à une application donnée. En particulier, le modèle d'a priori de proximité que nous proposons, défini à partir des contraintes de paires du plus court chemin sur le graphe d'adjacence des objets, peut facilement être adapté pour tenir compte des relations spatiales entre les objets ciblés dans un problème donné. L'algorithme de segmentation peut être adapté aux besoins de l'application en termes de temps d'exécution et de capacité de stockage à l'aide d'une partition de l'image à segmenter par une tesselation de Voronoï efficace et contrôlable, établissant un bon équilibre entre la compacité des régions et le respect des frontières des objets. Des évaluations et comparaisons qualitatives et quantitatives avec le modèle de Potts standard confirment que notre modèle d'a priori apporte des améliorations significatives dans la segmentation d'objets distincts d'intensités similaires, dans le positionnement précis des frontières des objets ainsi que dans la robustesse de segmentation par rapport à la résolution de partition. L'évaluation comparative de la méthode de partition avec ses concurrentes confirme ses avantages en termes de temps d'exécution et de qualité des partitions produites. Par comparaison avec l'approche appliquée directement sur les voxels de l'image, l'étape de partition améliore à la fois le temps d'exécution global et l'empreinte mémoire du processus de segmentation jusqu'à un ordre de grandeur, sans compromettre la qualité de la segmentation en pratique. / We develop a generic Graph Cut-based semiautomatic multiobject image segmentation method principally for use in routine medical applications ranging from tasks involving few objects in 2D images to fairly complex near whole-body 3D image segmentation. The flexible formulation of the method allows its straightforward adaption to a given application.\linebreak In particular, the graph-based vicinity prior model we propose, defined as shortest-path pairwise constraints on the object adjacency graph, can be easily reformulated to account for the spatial relationships between objects in a given problem instance. The segmentation algorithm can be tailored to the runtime requirements of the application and the online storage capacities of the computing platform by an efficient and controllable Voronoi tessellation clustering of the input image which achieves a good balance between cluster compactness and boundary adherence criteria. Qualitative and quantitative comprehensive evaluation and comparison with the standard Potts model confirm that the vicinity prior model brings significant improvements in the correct segmentation of distinct objects of identical intensity, the accurate placement of object boundaries and the robustness of segmentation with respect to clustering resolution. Comparative evaluation of the clustering method with competing ones confirms its benefits in terms of runtime and quality of produced partitions. Importantly, compared to voxel segmentation, the clustering step improves both overall runtime and memory footprint of the segmentation process up to an order of magnitude virtually without compromising the segmentation quality. Imagerie médicale Traitement des images Traitement numérique des images Segmentation Image 3D Partition d'images Modèle de Markov A priori spatial Coupure de graphes Medical Imaging Image Processing Digital Images Processing Image segmentation 3D Imaging Image clustering Markov model Spatial prior Graph cuts 621.367 028 507 2
129	Performance analysis of EM-MPM and K-means clustering in 3D ultrasound breast image segmentation Yang, Huanyi 05 1900 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / Mammographic density is an important risk factor for breast cancer, detecting and screening at an early stage could help save lives. To analyze breast density distribution, a good segmentation algorithm is needed. In this thesis, we compared two popularly used segmentation algorithms, EM-MPM and K-means Clustering. We applied them on twenty cases of synthetic phantom ultrasound tomography (UST), and nine cases of clinical mammogram and UST images. From the synthetic phantom segmentation comparison we found that EM-MPM performs better than K-means Clustering on segmentation accuracy, because the segmentation result fits the ground truth data very well (with superior Tanimoto Coefficient and Parenchyma Percentage). The EM-MPM is able to use a Bayesian prior assumption, which takes advantage of the 3D structure and finds a better localized segmentation. EM-MPM performs significantly better for the highly dense tissue scattered within low density tissue and for volumes with low contrast between high and low density tissues. For the clinical mammogram, image segmentation comparison shows again that EM-MPM outperforms K-means Clustering since it identifies the dense tissue more clearly and accurately than K-means. The superior EM-MPM results shown in this study presents a promising future application to the density proportion and potential cancer risk evaluation. segmentation, EM-MPM, ultrasound Breast -- Ultrasonic imaging Image processing -- Digital techniques Bayesian statistical decision theory Tomography Digital images -- Noise Three-dimensional imaging in medicine Diagnostic imaging -- Data processing Cluster analysis -- Data processing Computer algorithms -- Research
130	Om informationstekniskt bevis Ekfeldt, Jonas January 2016 (has links) Information technology evidence consists of a mix of representations of various applications of digital electronic equipment, and can be brought to the fore in all contexts that result in legal decisions. The occurrence of such evidence in legal proceedings, and other legal decision-making, is a phenomenon previously not researched within legal science in Sweden. The thesis examines some of the consequences resulting from the occurrence of information technology evidence within Swedish practical legal and judicial decision-making. The thesis has three main focal points. The first consists of a broad identification of legal problems that information technology evidence entails. The second focal point examines the legal terminology associated with information technology evidence. The third focal point consists of identifying sources of error pertaining to information technology evidence from the adjudicator’s point of view. The examination utilizes a Swedish legal viewpoint from a perspective of the public trust in courts. Conclusions include a number of legal problems in several areas, primarily in regards to the knowledge of the adjudicator, the qualification of different means of evidence and the consequences of representational evidence upon its evaluation. In order to properly evaluate information technology evidence, judges are – to a greater extent than for other types of evidence – in need of (objective) knowledge supplementary to that provided by parties and their witnesses and experts. Furthermore, the current Swedish evidence terminology has been identified as a complex of problems in and of itself. The thesis includes suggestions on certain additions to this terminology. Several sources of error have been identified as being attributable to different procedures associated with the handling of information technology evidence, in particular in relation to computer forensic investigations. There is a general need for future research focused on matters regarding both standards of proof for and evaluation of information technology evidence. In addition, a need for deeper legal scientific studies aimed at evidence theory has been identified, inter alia regarding the extent to which frequency theories are applicable in respect to information technology evidence. The need for related further discussions on future emerging areas such as negative evidence and predictive evidence are foreseen. accountability audit trail authenticity computer evidence criminal procedure data quality digital evidence digital images digital traces electronic evidence evaluation of evidence evidence law evidence terminology evidential value evidentiary facts forensic evidence handling of evidence ict-evidence informatics information quality information representation information security it-evidence law and information technology legal evidence log log analysis machine identity means of evidence personal identity reliability representation information screen dump sources of error traceability validity autenticitet bevisfakta bevismedel bevishantering bevisprövning bevisrätt bevisterminologi bevisvärdering datakvalitet digitala bevis digitala bilder digitala spår elektroniska bevis elektroniska spår felkällor filer forensiska bevis ikt informatik informationskvalitet informationsrepresentation informationsteknik informationstekniskt bevis it-bevis it-säkerhet juridiskt bevis logganalys maskinell identitet personell identitet principen om fri bevisprövning representationsinformation riktighet rättsinformatik skärmdump spårbarhet straffprocessrätt

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