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Stratégie de perception active pour l'interprétation de scènes / Active Perception’s Strategy for scene’s interpretationBernay-Angeletti, Coralie 29 June 2016 (has links)
La perception est le moyen par lequel nous connaissons le monde extérieur. C’est grâce à nos perceptions que nous sommes capables d’interagir avec notre environnement et d’accomplir de nombreuses actions du quotidien comme se repérer, se déplacer, reconnaître des objets et autres. Cette perception n’est pas juste passive comme peut l’être une sensation, elle comporte des aspects actifs. En particulier, elle peut être orientée dans un but précis, permettant de filtrer les données pour ne traiter que les plus pertinentes. Si la perception humaine est particulièrement efficace, la perception artificielle, elle, demeure un problème complexe qui se heurte à de nombreuses difficultés. Ainsi, les changements de conditions de perception comme des modifications de l’illumination ou des occultations partielles de l’objet à percevoir doivent pouvoir être gérées efficacement. Pour résoudre ces difficultés, s’inspirer de la perception humaine semble être une piste intéressante. Ce manuscrit propose un système de perception polyvalent et générique reposant sur une stratégie de perception active. Pour ce faire, nous proposons un algorithme Top-Down utilisant un modèle en parties. Le problème de perception est transformé en un problème d’estimation d’un vecteur de caractéristiques. La détection des différentes parties permet de réaliser cette estimation. Le système de perception proposé est un algorithme itératif multi-capteurs. À chaque itération, il sélectionne au mieux, en fonction des objectifs fixés par l’application, la partie à détecter ainsi que les meilleurs capteur et détecteur compatibles. Un réseau bayésien est utilisé pour prendre en compte les événements incertains pouvant survenir lors de ce processus comme la défaillance d’un détecteur ou la non existence potentielle d’une partie donnée. Un processus de focalisation à la fois spatiale et de caractéristiques permet d’améliorer la détection en augmentant le rapport signal sur bruit, en restreignant la zone de recherche pour une partie et en éliminant certains des candidats trouvés. Ce processus de focalisation permet aussi de réduire les temps de calcul et de restreindre l’influence des distracteurs. L’ajout de nouveaux capteurs, détecteurs ou parties se fait simplement. De plus, l’utilisation d’un réseau bayésien permet une grande flexibilité au niveau de la modélisation des événements pris en compte : il est facile de rajouter de nouveaux événements pour obtenir une modélisation plus réaliste. L’algorithme proposé a été utilisé pour plusieurs applications incluant de la reconnaissance d’objets, de l’estimation fine de pose et de la localisation. / Perception is the way by which we know the outside world. Thanks to our perceptions we are able to interact with our environment and to achieve various everyday life actions as locating or moving in an environment, or recognizing objects. Perception is not passive whereas sensations are, it has active components. In particular, perception can be oriented for a specific purpose allowing to filter data and to take care only of the most relevant. If human perception is particularly effective, artificial perception remains a complex problem with a lot of non solved difficulties. For example, changes of perception conditions as modification of illumination or partial occultation of the searched object must be effectively managed. This thesis proposes a system of perception based on a strategy of active perception which can adapt itself to various applications. To do it, we propose an algorithm Top-Down using a part-based model. The problem of perception is transformed into a problem of estimation of a characteristics vector. The detection of the different parts constituting the searched object allows to realize this estimation. The proposed perceptive system is an iterative and multi-sensors algorithm. In every iteration, it selects, at best, according to the application objectives, the part to detect and the best compatible sensor and detector. A bayesian network is used to take into account uncertain events which can arise during this process as detector failure or potential non existing part. A focus process consisting of a spatial focus and of a characteristics focus, improves the detection by restricting the search area, by improving the signal to noise ratio and by eliminating some erroneous candidates. This focus process also allows to reduce computation time and to restrict influence of distractors. Adding a part, a sensor or a detector is simple. Furthermore, the use of a bayesian network allows to be flexible in the events modelisation : it is easy to add new events to obtain a more realistic modelisation. The proposed algorithm has been used for several applications including object’s recognition, fine pose estimation and localization. So, it is multi-purpose and generic.
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Inter-county Migration in the United States Before, During and After the Great Recession: Exploring County Migration Patterns between 2001 and 2010Yamoah, Owusua January 2019 (has links)
No description available.
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3D rekonstrukce objektů pomocí metod analýzy obrazu / Objects 3D reconstruction using image processing methodsMaruniaková, Zuzana January 2018 (has links)
This diploma thesis deals with 3D reconstruction of objects using image analysis methods. The work includes mathematical theory associated with this problem, a procedure for creating 2D sharp images and 3D reconstruction itself. The outputs are 2D sharp images, 3D models, stl models. Different kinds of data are analyzed.
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Dynamická fokusace v ultrazvukové tomografii / Dynamic Focusing in Ultrasound TomographyKratochvíla, Jiří January 2010 (has links)
The aim of the master’s thesis, is to get acquainted with the dynamic focusing in conventional ultrasound systems, to modify this method for ultrasound computer tomography and to realize and interpret this modification on simulated and real data in a transparent graphic interface. The modification of the dynamic focusing was executed for the 3D ultrasound computer tomograph developed in Karlsruhe. Simulated data, that are necessary for focusing, were generated by existing program, which was adjusted. The new created program of the dynamic focusing was tested and evaluated with those simulated and real data.
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Časová interpolace oftalmologických videosekvencí pomocí multimodálního lícování / Temporal interpolation of ophthalmologic video sequencies using multimodal registrationKadla, Jan January 2014 (has links)
This master’s thesis gives a description of fundus camera as a medical imaging system. Sub features of this system are explained in short, thus examples of certain construction variants are given. Furthermore, the work deals with image fusion and associated possibilities of digital image processing. One set of consecutive scanned images of human eye’s retina has been provided for the practical part of this work. During program processing of these data, decomposition of obtained images to single-color sequences is performed. For these partial monochromatic sequences, monomodal registration is performed, based on calculation of the brightness similarity criterion between the pairs of images. From the three created monochromatic sequences of registered images, new sequence of color images is created, using multimodal registration of each image triples. As a basis for similarity evaluation during multimodal registration, an information similarity criterion was used.
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Charakterizace nízkomolekulárních syntetických markerů izoelektrických bodů kapilární zónovou elektroforézou a kapilární izoelektrickou fokusací / Characterization of low-molecular-mass synthetic markers of isoelectric points by capillary zone electrophoresis and capillary isoelectric focusingBrandejsová, Martina January 2012 (has links)
High-performance electromigration separation methods, capillary zone electrophoresis (CZE) and capillary isoelectric focusing (CIEF), have been applied to physico-chemical characterization of new synthetic low-molecular mass markers of isoelectric points. Amphoteric compounds on the basis of aminomethylnitrophenols, their derivatives and other structurally related substances were analyzed by CZE in a series of background electrolytes in a wide pH range, 1.86 - 11.18. From the measured pH dependencies of effective electrophoretic mobilities of analytes (beforehand corrected to reference temperature of 25 řC), their isoelectric points (pI) were determined. In addition, using the non-linear regression analysis of the above dependencies, acid-base dissociation constants (pKa) of ionogenic groups of selected analytes were calculated. Subsequently, the analytes with sharply defined isoelectric points were analyzed by CIEF. CIEF confirmed applicability of these compounds as markers of isoelectric points for calibration of pH gradient in CIEF in the determination of pI of amphoteric compounds, especially peptides and proteins. The determined pKa values of ionogenic groups in particular compounds will be utilized in the development of new pI markers with desired pI values.
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Gradient-Index Metamaterial Infrared Detector for Enhanced Photo-Response and Image QualityAdams, Kelsa Derek 05 1900 (has links)
An enhanced thermal imaging concept made possible through the development of a gradient-indexed metamaterial infrared detector that offers broadband transmission and reflection in THz waves. This thesis proposes a proof of feasibility for a metamaterial infrared detector containing an anti-reflective coating with various geometrically varying periodic metasurfaces, a gradient-indexed dielectric multilayer for near-perfect longpass filtering, and a gradient index of refraction (GRIN) metalens for enhanced focal plane thermal imaging. 2D Rigorous Coupled-Wave Analysis (RCWA) is used for understanding the photonic gratings performance based on material selection and varying geometric structure. Finite Difference Time Domain (FDTD) is used to characterize performance for a diffractive metalens by optimizing the radius and arrangement of cylindrical nanorods to create a desired phase profile that can achieve a desired focal distance for projections on a detector for near- to far-infrared thermal imaging. Through combining a micromachined anti-reflective coating, a near-perfect longpass filter, and metamaterial GRIN metalens, infrared/THz focal plane thermal imaging can obtain faster photo-response and image quality at targeted wavelengths, which allows for scientific advancements in electro-optical devices for the Department of Defense, aerospace, and biochemical detection applications.
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Design of Acoustic Lenses for Ultrasound Focusing ApplicationsPérez López, Sergio 17 January 2022 (has links)
Tesis por compendio / [ES] La focalización de ultrasonidos tiene muchas aplicaciones en una gran variedad de áreas tanto científicas como industriales. Los ultrasonidos focalizados son una de las herramientas principales usada por médicos en todo el mundo para obtener imágenes biomédicas de diferentes tipos de tejidos y órganos de manera no invasiva. En las últimas décadas, el uso de ultrasonidos focalizados de alta intensidad (HIFU, por sus siglas en inglés) ha surgido como una de las técnicas principales para el tratamiento de cáncer mediante la ablación térmica de tumores de manera no invasiva. Además, los ultrasonidos focalizados están emergiendo en los últimos años como uno de los métodos más prometedores para el tratamiento de las enfermedades cerebrales, con la aparición de nuevas técnicas disruptivas como la apertura reversible de la barrera hematoencefálica o la neuromodulación. En entornos industriales, los ultrasonidos son ampliamente utilizados como uno de los métodos principales para la evaluación no destructiva de materiales y estructuras, debido a que las ondas acústicas pueden penetrar en los objetos a distancias donde la luz no puede debido a la elevada absorción y dispersión. En este sentido, diseñar estructuras capaces de focalizar ultrasonidos es de una gran relevancia tanto para la comunidad científica como para los sectores médicos e industriales.
Esta tesis presenta nuevos diseños de lentes acústicas capaces de controlar los parámetros principales del haz de ultrasonidos focalizados, proporcionando diferentes tipos de perfiles de focalización adecuados para una gran variedad de aplicaciones y escenarios. En particular, se han diseñado y adaptado al campo de los ultrasonidos las lentes de Fresnel (Fresnel Zone Plates, FZPs), ampliamente utilizadas en el campo de la óptica. Se ha presentado una nueva técnica de modulación espacio-temporal capaz de controlar la posición del foco de ultrasonidos tanto en espacio como en tiempo, aumentando así la versatilidad de este tipo de dispositivos. También se ha demostrado el funcionamiento en el campo de la acústica de nuevos diseños basados en aplicar secuencias binarias a una lente de Fresnel convencional, como las secuencias fractales de Cantor o las secuencias de M-bonacci generalizadas, capaces de modificar las propiedades de focalización de las lentes, incluyendo el número, posición y forma de los focos acústicos. Además, se introduce un nuevo diseño de lentes esféricas rellenas de líquido capaces de generar jets ultrasónicos, con mucho potencial en aplicaciones de imagen de alta resolución en campo cercano. Se ha demostrado que, cambiando el líquido interno de la lente o ajustando el ratio de mezcla entre dos líquidos, se pueden controlar los parámetros principales del jet. Los diseños propuestos en la tesis han sido validados tanto empleando simulaciones numéricas como realizando medidas experimentales, allanando el camino para el uso de este tipo de estructuras en aplicaciones de focalización de ultrasonidos. / [CA] La focalització d'ultrasons té moltes aplicacions en moltes àrees científiques i industrials. Els ultrasons focalitzats són una de les eines principals utilitzada per metges a tot el món per obtenir imatges biomèdiques de diferents tipus de teixits i òrgans de manera no invasiva. En les últimes dècades, els ultrasons focalitzats d'alta intensitat (HIFU, per les seues sigles en anglès) han aparegut com una de les tècniques principals per al tractament de càncer mitjançant l'ablació de tumors de manera no invasiva. A més, els ultrasons focalitzats estan emergint en els últims anys com un dels mètodes més prometedors per al tractament de les malalties cerebrals, amb l'aparició de noves tècniques disruptives com l'obertura reversible de la barrera hematoencefàlica o la neuromodulació. En entorns industrials, els ultrasons són àmpliament utilitzats com un dels mètodes principals per a l'avaluació no destructiva de materials i estructures, pel fet que les ones acústiques poden penetrar en els objectes a distàncies on la llum no pot a causa de l'elevada absorció i dispersió. En aquest sentit, dissenyar estructures capaces de focalitzar ultrasons és d'una gran rellevància tant per a la comunitat científica com per als sectors mèdics i industrials.
Aquesta tesi presenta nous dissenys de lents acústiques capaços de controlar els paràmetres principals del feix d'ultrasons focalitzats, proporcionant diferents tipus de perfils de focalització adequats per a una gran varietat d'aplicacions i escenaris. En particular, s'han dissenyat i adaptat al camp dels ultrasons les lents de Fresnel (Fresnel Zone Plates, FZPs), àmpliament utilitzades en el camp de l'òptica. S'ha presentat una nova tècnica de modulació espai-temporal capaç de controlar la posició del focus d'ultrasons tant en espai com en temps, augmentant així la versatilitat d'aquest tipus de dispositius. També s'ha demostrat el funcionament en el camp de l'acústica de nous dissenys basats en aplicar seqüències binàries a una lent de Fresnel convencional, com les seqüències fractals de Cantor o les seqüències de M-bonacci generalitzades, capaces de modificar les propietats de focalització de les lents, incloent el nombre, posició i forma dels focus acústics. A més, s'introdueix un nou disseny de lents esfèriques plenes de líquid capaces de generar jets ultrasònics, amb molt potencial en aplicacions d'imatge d'alta resolució en camp proper. S'ha demostrat que, canviant el líquid intern de la lent o ajustant la ràtio de barreja entre dos líquids, es poden controlar els paràmetres principals del jet. Els dissenys proposats en la tesi han estat validats tant emprant simulacions numèriques com realitzant mesures experimentals, aplanant el camí per a l'ús d'aquest tipus d'estructures en aplicacions de focalització d'ultrasons. / [EN] Ultrasound focusing has many applications in a wide range of fields. Focused ultrasound is one of the main tools used by doctors all over the world to obtain biomedical images of different kind of tissues non-invasively. In the past decades, high intensity focused ultrasound (HIFU) appeared as one of the fundamental techniques for cancer treatment through non-invasive thermal tumor ablation. In addition, focused ultrasonic waves are recently emerging as one of the main tools to treat brain diseases, with novel disruptive techniques such as blood-brain barrier opening or neuromodulation. In industrial environments, ultrasonic waves are widely employed as one of the primary methods for the non-destructive evaluation (NDE) of materials and structures, as acoustic waves are able to penetrate deep into objects otherwise opaque using optical techniques. In this sense, designing structures capable of focusing ultrasonic waves is of great interest and relevance for the scientific, the industrial, and the biomedical sectors.
This thesis devises new designs of acoustic lenses capable of controlling the main parameters of the focused ultrasound beam, achieving different kinds of focusing profiles suitable for a wide variety of scenarios. In particular, Fresnel Zone Plates (FZPs), commonly used in optics, are designed and adapted to the ultrasound domain. A novel spatio-temporal modulation technique capable of controlling the ultrasound focus location in both time and space is presented, increasing the versatility of this kind of devices. New design techniques based on applying a binary sequence to FZPs are also demonstrated, such as Cantor fractal sequences or generalized M-bonacci sequences, which modify the focusing properties of the lens, including the number, location, and shape of the different acoustic foci. In addition, acoustic jets generated by liquid-filled spherical lenses are devised for near-field high resolution imaging, demonstrating their applicability in the ultrasound domain. It is demonstrated that, by changing the inner liquid of the spherical lens or by tuning the mixing ratio between two liquids, the main focal parameters of the ultrasonic jet can be accurately controlled. The proposed designs are validated using both numerical simulations and experimental measurements, paving the way for the use of these kind of structures in focused ultrasound applications. / This work would not have been possible without the following funding
sources: PAID-01-18 personal FPI grant from Universitat Politècnica de València; Spanish government MINECO TEC2015-70939-R project; Spanish government MICINN RTI2018-100792-B-I00 project; Generalitat Valenciana AICO/2020/139 project. / Pérez López, S. (2021). Design of Acoustic Lenses for Ultrasound Focusing Applications [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/179907 / TESIS / Compendio
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Numerical Investigation of Internal Wave-Vortex Dipole InteractionsBlackhurst, Tyler D. 14 March 2012 (has links) (PDF)
Three-dimensional linear ray theory is used to investigate internal waves interacting with a Lamb-Chaplygin pancake vortex dipole. These interactions involve waves propagating in the same (co-propagating) and opposite (counter-propagating) horizontal directions as the dipole translation. Co-propagating internal waves in the vertical symmetry plane between the vortices of the dipole can approach critical levels where the wave energy is absorbed by the dipole or where the waves are overturned and possibly break. As wave breaking cannot be simulated with this linear model, changes in wave steepness are calculated to aid in estimating the onset of breaking. Counter-propagating internal waves in the vertical symmetry plane can experience horizontal and vertical reflections, including turning points similar to waves in two-dimensional steady shear. Wave capture is also a possible effect of either type of interaction, depending on initial wave properties and positioning relative to the vortex dipole. Away from the vertical symmetry plane, a spanwise converging (focusing) and diverging (defocusing) of wave energy is observed in co- and counter-propagating interactions as symmetric off-center rays interact with the dipole's individual vortices. Some off-center rays experience multiple horizontal refractions similar to wave trapping.
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Validation of anti-cytokeratin antibodies used in rapid cancer diagnostics by isoelectric focusing and QCM technologyKostines, Reneh January 2021 (has links)
Antibodies are Y-shaped proteins. In the human body, antibodies areproduced by plasma cells, mainly T and B cells which are included inthe adaptive immune system. The production of antibodies is stimulatedby antigens. The binding between an antigen-specific antibody and itsantigen can be like the interconnect between a lock and a key.Therefore, antibodies are widely used as diagnostic tools for avariety of diseases but most importantly cancer. Some rapid diagnostictests are completely dependent on the specificity and reactivity ofantibodies such as UBC® Rapid produced by IDL Biotech AB. Therefore,the quality of these antibodies is important. This master thesis at IDL Biotech aimed to validate six anticytokeratinantibodies that are currently used in several rapid cancerdiagnostic tests produced by IDL. Antibody validation is a processwhere specificity, selectivity and reproductivity of an antibody isdemonstrated through specific laboratory investigations. During thisthesis, two laboratory methods were used to validate antibodies,namely, isoelectric focusing electrophoresis and the Attana QuartzCrystal Microbalance based biosensor. Isoelectric focusing electrophoresis (IEF) is a method that determinesproteins pI-values which can then reveal information about posttranslationalmodifications and protein sustainability during storage.IEF revealed changes in pI-values in two antibodies: AB2 and AB4. Attana biosensor analysis on AB1-5 showed that all antibodies havehigh specificity, reactivity and relatively high affinity to theircytokeratin targets. It also revealed that 4 antibodies (AB1 and AB3-5) have lower cross-reactivity with other cytokeratins than theirtarget cytokeratins compared to AB2. Keywords: Antibody validation, Isoelectric focusing, QCM, Attanabiosensor, biosensors, rapid diagnostics, epithelial carcinomas.
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