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Real-time 3D Semantic Segmentation of Timber Loads with Convolutional Neural NetworksSällqvist, Jessica January 2018 (has links)
Volume measurements of timber loads is done in conjunction with timber trade. When dealing with goods of major economic values such as these, it is important to achieve an impartial and fair assessment when determining price-based volumes. With the help of Saab’s missile targeting technology, CIND AB develops products for digital volume measurement of timber loads. Currently there is a system in operation that automatically reconstructs timber trucks in motion to create measurable images of them. Future iterations of the system is expected to fully automate the scaling by generating a volumetric representation of the timber and calculate its external gross volume. The first challenge towards this development is to separate the timber load from the truck. This thesis aims to evaluate and implement appropriate method for semantic pixel-wise segmentation of timber loads in real time. Image segmentation is a classic but difficult problem in computer vision. To achieve greater robustness, it is therefore important to carefully study and make use of the conditions given by the existing system. Variations in timber type, truck type and packing together create unique combinations that the system must be able to handle. The system must work around the clock in different weather conditions while maintaining high precision and performance.
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Segmentação, classificação e quantificação de bacilos de tuberculose em imagens de baciloscopia de campo claro através do emprego de uma nova técnica de classificação de pixels utilizando máquinas de vetores de suporteXavier, Clahildek Matos 02 July 2012 (has links)
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Previous issue date: 2012-07-02 / Não Informada / Tuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis that primarily affects the lungs and reaches over 8.8 million people worldwide. Although the number of cases of TB disease and deaths has fallen over the past years, this disease still remains a serious health problem in developing countries. Currently, as initial tests for the diagnosis of TB are used methods of smear bright field and fluorescence. The first is used mostly in developing countries, due to low cost, the second is the preferred method in developed countries to be more sensitive. Among the many challenges for the control of this disease is the development of a rapid, efficient and low cost for the diagnosis of tuberculosis. The process of diagnosis of smear-field course is time consuming, manual and error-prone, so that there is a high rate of false negatives. Various techniques for pattern recognition in the image smear bright field microscopy have been designed to recognize and count of the rods. This paper describes a new method for segmentation of
tubercle bacilli in sputum bright field. The method proposed in this dissertation uses a classifier consisting of a support vector machine. The differential method is proposed in the variables selected for the input of the classifier. They were selected from four color spaces: RGB, HSI, YCbCr and Lab used to both individual characteristics such as subtractions of characteristics of the same color space and different color spaces. We investigated a total of 30 features. The best features were selected using the selection technique scalar features. With the proposed method was reached a sensitivity of 94%. However, further steps for noise reduction are required to minimize the classification errors. / A tuberculose (TB) é uma doença contagiosa causada pelo Mycobacterium tuberculosis que afeta, principalmente, os pulmões e atinge mais de 8,8 milhões de pessoas em todo o mundo. Embora o número de casos de doenças e mortes por TB tenham caído ao longo dos últimos anos, essa doença ainda continua sendo um grave problema de saúde nos países em desenvolvimento. Atualmente, como exames iniciais para o diagnóstico da TB são usados os métodos de baciloscopia de campo claro e baciloscopia de fluorescência. O primeiro é mais usado em países em desenvolvimento, devido ao baixo custo; o segundo é o método preferencial em países desenvolvidos por ser mais sensível. Entre os vários desafios para o
controle dessa doença, está o desenvolvimento de um método rápido, eficiente e de baixo custo para o diagnóstico da TB. O processo de diagnóstico de baciloscopia de campo claro é demorado, manual e propenso a erros, fazendo com que haja uma alta taxa de falsos negativos. Várias técnicas de reconhecimento de padrão em imagens baciloscópicas de microscopia de campo claro têm sido desenvolvidas para o reconhecimento e contagem dos bacilos. Este trabalho descreve um novo método para segmentação de bacilos da tuberculose em baciloscopia de campo claro. O método proposto utiliza um classificador constituído por uma máquina de vetores de suporte. O diferencial do mesmo em relação a outros trabalhos está nas variáveis selecionadas para a entrada do classificador. Essas variáveis foram
selecionadas a partir de quatro espaços de cor: RGB, HSI, YCbCr e Lab. Investigou-se tanto características individuais, como subtrações de características de um mesmo espaço de cor e de espaços de cores diferentes, num total de 30 características. As melhores características foram selecionadas utilizando-se a técnica de seleção escalar de características. Alcançou-se uma sensibilidade de 94%. No entanto, novas etapas para a redução de ruído são necessárias para minimizar os erros de classificação.
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Painting in the twenty-tens;where to now? : (You can’t touch this!)Olofsson, Max January 2012 (has links)
The essay is a manifesto-like personal take on painting, and a redefinition of painting in the digital age. Careless usage of the term ”painting” has led to a diluted descriptive function and a waning categorizing capacity; almost anything can be called painting, which in turn puts actual painting in an awkward position – where it, apart from being itself, could be almost anything. The term “painthing” is introduced to distinguish painting from works that beside its two-dimensional visual information also makes a point of its specific materiality. It brings up cave paintings and links to video-games, suggesting that video-games have gone through the reversed evolution of the history of painting – from abstraction to representation. It speaks of the problems of documentation – the translation of visual information (or re-flattening of a flat surface) – and the cultural equalization of information and images on the internet through the common denominator the pixel. It also describes “information painting”, which in short is digital painting where there is no physical object to be translated to a documentation of itself, but rather a painting that is original in its documentation form (its digital form), painting that strives to be nothing but the utopia of an image – the untouchable/unreachable visual information.
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Optimering av sampling quality-parametrar för Mental RayKarlsson, Linus January 2011 (has links)
Fotorealistiska 3d-bilder används idag inom ett brett spektrum av branscher. Framställningen av denna typ av grafik kräver ofta väldigt mycket datorkraft. Vid rendering med renderingsmotorer som använder sig av raytracing algoritmer är aliasing ett medfött problem. Lösningen heter anti-aliasing som arbetar för att undvika aliasing artefakter som jagged edges eller Moiré-effekter med mera. En del av anti-aliasingprocessen är supersampling som ofta kräver mycket datorkraft. Att optimera parametrar för supersampling är därför mycket viktigt. Det är möjligt att genom optimering spara väldigt mycket datorkraft och därmed tid. Detta arbete innehåller resultat från experiment där deltagare får bedöma bilder med olika kvalité av anti-aliasing. Resultaten av dessa experiment kan användas som referens vid optimering av renderingsparametrar för anti-aliasing vid rendering med hjälp av Mental Ray.
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Using remotely-sensed habitat data to model space use and disease transmission risk between wild and domestic herbivores in the African savannaKaszta, Zaneta 29 June 2017 (has links)
The interface between protected and communal lands presents certain challenges for wildlife conservation and the sustainability of local livelihoods. This is a particular case in South Africa, where foot-and-mouth disease (FMD), mainly carried by African buffalo (Syncerus caffer) is transmitted to cattle despite a fence surrounding the protected areas.The ultimate objective of this thesis was to improve knowledge of FMD transmission risk by analyzing behavioral patterns of African buffalo and cattle near the Kruger National Park, and by modelling at fine spatial scale the seasonal risk of contact between them. Since vegetation is considered as a primary bottom-up regulator of grazers distribution, I developed fine-scale seasonal mapping of vegetation. With that purpose, I explored the utility of WorldView-2 (WV-2) sensor, comparing object- (OBIA) and pixel-based image classification methods, and various traditional and advanced classification algorithms. All tested methods produced relatively high accuracy results (>77%), however OBIA with random forest and support vector machines performed significantly better, particularly for wet season imagery (93%).In order to investigate the buffalo and cattle seasonal home ranges and resource utilization distributions I combined the telemetry data with fine-scale maps on forage (vegetation components, and forage quality and quantity). I found that buffalo behaved more like bulk feeders at the scale of home ranges but were more selective within their home range, preferring quality forage over quantity. In contrast, cattle selected forage with higher quantity and quality during the dry season but behaved like bulk grazers in the wet season.Based on the resource utilization models, I generated seasonal cost (resistance) surfaces of buffalo and cattle movement through the landscape considering various scenarios. These surfaces were used to predict buffalo and cattle dispersal routes by applying a cumulative resistant kernels method. The final seasonal contact risks maps were developed by intersecting the cumulative resistant kernels layers of both species and by averaging all scenarios. The maps revealed important seasonal differences in the contact risk, with higher risk in the dry season and hotspots along a main river and the weakest parts of the fence. Results of this study can guide local decision makers in the allocation of resources for FMD mitigation efforts and provide guidelines to minimize overgrazing. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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Parallel Tomographic Image Reconstruction On Hierarchical Bus-Based And Extended Hypercube ArchitecturesRajan, K 07 1900 (has links) (PDF)
No description available.
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Optimisation of the ILC vertex detector and study of the Higgs couplings / Développement d'un détecteur de vertex de nouvelle génération pour le collisionneur ILC : impact sur la détermination des rapports d'embranchement du boson de Higgs standardVoutsinas, Georgios 28 June 2012 (has links)
Cette thèse est une contribution au document intitulé "Detector Baseline Document (DBD)" décrivant le conceptde détecteur ILD envisagé auprès du collisionneur linéaire international électron-positon ILC (acronyme del'anglais International Linear Collider).Les objectifs de physique de l'ILD nécessitent un détecteur de vertex (VXD) particulièrement léger, rapide et trèsgranulaire permettant d'atteindre une résolution sans précédent sur le paramètre d'impact des trajectoiresreconstruites des particules produites dans les interactions étudiées. Le principal objectif de cette thèse est demontrer comment optimiser les paramètres du VXD dans le cas ou il est composé de Capteurs à Pixels Actifsfabriqués en technologie industrielle CMOS (CAPS). Ce travail a été réalisé en étudiant la sensibilité desperformances d'étiquetage des saveurs lourdes et de la précision sur les rapports d'embranchement hadroniquedu boson de Higgs aux différents paramètres du VXD.Le cahier des charges du VXD, particulièrement ambitieux, a nécessité le développement d'une nouvelletechnologie de capteurs de pixels de silicium, les CAPS, dont le groupe PICSEL de l'IPHC est à l'origine. Lavitesse de lecture et l'influence des paramètres qui régissent la fabrication des capteurs en fonderie ont étéétudiées dans cette thèse, et des prototypesde CAPS ont été caractérisés sur faisceau de particules. Enfin, les performances de trajectométrie d'un VXDcomposé de CAPS a été évalué avec des études de simulation. / This thesis is a contribution to the " Detector Baseline Document ", describing the ILD detector which is intendedfor the International Linear Collider (ILC).The physics goals of the ILD call for a vertex detector (VXD) particularly light, rapid and very granular allowing toreach an unprecedented resolution on the impact parameter of the tracks that reconstruct the particles producedin the studied interactions. The principle goal of this thesis is to show how to optimise the parameters of the VXDin the case that is composed of Active Pixel Sensors manufactured in industrial CMOS technology (CAPS). Thiswork has been realised by studying the sensitivity of the performance of the heavy flavour tagging and theprecision on the hadronic branching fractions of the Higgs boson as a function of different sets of VXDparameters.The specifications of the VXD, particularly ambitious, call for the development of a novel silicon pixel sensorstechnology, the CAPS, which was pioneered by the PICSEL group of IPHC. The readout speed and the influenceof the fabrication parameters have been studied in this thesis, and CAPS prototypes have been characterised intest beams. Finally, the tracking performance of a CAPS based VXD has been evaluated with simulation studies.
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Search for the production of four top quarks in proton-proton collisions at $\sqrt{s}=13$ TeV in the single lepton and opposite-sign dilepton channels with the ATLAS detector at the Large Hadron ColliderSabatini, Paolo 10 February 2020 (has links)
No description available.
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Introduction à la reconstruction 3D par lumière structuréeHurtubise, Nicolas 11 1900 (has links)
Ce mémoire porte sur la reconstruction 3D active par la lumière structurée et se veut une introduction au travers d'une vue d'ensemble du domaine.
L'accent est mis sur une compréhension des différents aspects du scan 3D, en commençant par l'acquisition du matériel et en allant jusqu'au calcul d'un modèle 3D. Les défis techniques les plus fréquents dans un contexte de scan 3D avec de l'équipement à faible coût sont abordés, de façon à donner une idée générale des problèmes à anticiper à quelqu'un qui souhaiterait se lancer dans la conception ou l'utilisation de ce type de scanneur. Afin d'aider à peser les forces et faiblesses de chaque algorithme formant l'état de l'art actuel en lumière structurée, une revue des différentes stratégies existantes est également donnée.
L'étude du domaine a mené à une contribution sous la forme d'un article, qui a été intégré dans le chapitre 6. Cet article propose une amélioration en ce qui concerne la performance et la précision d'un algorithme de scan 3D existant et a été publié dans la International Virtual Conference on 3D Vision en novembre 2020. / This thesis focuses on active 3D reconstruction with structured light and is intended to be an introduction through an overview of the field.
It is focused on understanding the different aspects of a 3D scanner, from the acquisition of the material to the final mesh reconstruction. The most common technical difficulties that arise in the context of low-cost 3D scanning are addressed, to give a general idea of the potential technical problems that may occur when using a DIY 3D scanner built from scratch. To help assess the strengths and weaknesses of each algorithm of the current state of the art in structured light, a review of the different strategies is also proposed.
The study of this domain led to the contribution of a paper, presented here in its entirety in chapter 6. This paper describes an improvement of an existing algorithm, both in terms of performance and precision, and was published in the International Virtual Conference on 3D Vision in November 2020.
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Upgrade of the ATLAS Experiment Inner Tracker and related physics perspectives of the Higgs boson decay into two b quarks / Amélioration du trajectographe de l’expérience ATLAS et impact sur l’étude de la désintégration du boson de Higgs en deux quarks bDucourthial, Audrey 26 October 2018 (has links)
Le LHC entrera dans sa phase à haute luminosité vers 2027 et pour profiter de l’augmentation importante du taux de collisions, ATLAS, et plus particulièrement son trajectographe doivent être améliorés en terme de résistance aux radiations et traitement de données à un taux accru. Grace au nouveau design du trajectographe at à l’amélioration d’algorithmes d’étiquetage des saveurs de jets, l’identification de jets issus de la désintégration de B hadrons sera facilitée et des canaux de physique possédant des quarks b dans leurs états finaux seront plus facilement accessible, parmi lesquels le couplage trilinéaire du boson de Higgs. La résistance aux raditions des capteurs à pixels en silicium joue un rôle primordial dans leur utilisation auprès des experience LHC. La quantification de l’impact des rayonnements sur les capteurs silicium est un enjeu crucial : un outil de digitisation des dommages des rayonnements a été développé pour modéliser l’impact des radiations dans les simulations Monte Carlo d’ATLAS. Le test de capteurs à pixels planaires, développés par le LPNHE et la fonderie FBK, constitue la partie principale de cette thèse. Les trois productions de capteurs testées possèdent plusieurs designs technologiques. Pour maximiser l’acceptance géométrique du détecteur, des capteurs à bord mince ont été développés. Deux options de polarisation durant les phases de test ont ausssi été étudiée. Les capteurs ont été testés à plusieurs phases d’irradiation. L’optimisation d’algorithme de b-tagging basé sur la reconstruction de vertex secondaire sera aussi présentée, ainsi qu’une étude concernant les performances du b-tagging à haut pT . / By 2027, the LHC will enter its high luminosity regime, providing protons protons collisions at an unprecedented rate. The LHC experiments whill have to be upgraded to cope with this higher data rate. The new ATLAS Inner Tracker (ITk) will allow a better identification of b-quarks and interesting physics signature with b-quarks in the final states such as the Higgs trilinear coupling will be reachable. The work performed during this thesis consisted in testing planar pixel sensors for the ITk, as well as optimizing b-tagging algorithms. In parallel, a study on the radiation damage on silicon pixel sensors have been performed. The radiation hardness of silicon sensors plays a determinant role as it allows them to be efficient in the highly radiative environment at LHC. Understanding the impact of radiation in silicon sensors is a major challenge and a radiation damage digitizer which models radiation damage effects in ATLAS Monte Carlo simulations is currently developed by the ATLAS experiment. Three ITk silicon planar pixel sensors productions of LPNHE and FBK have been developed, produced and tested on beam. Sensors from these three productions aim to be part of the ITk and have to demonstrate good performance after being irradiated at high fluences. Several technological designs have been investigated, such as temporary metal biasing option and active edges which maximize the geometrical acceptance of the sensors. The optimization of b-tagging SV1 algorithm (a secondary-vertex based algorithm) will be pre- sented as well as a study on the extrapolation of b-tagging performances at high pT.
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