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La identificación de los parámetros dinámicos que constituyen el modelo dinámico de un robot manipulador tiene por objeto la estimación de valores precisos de dichos parámetros a partir de medidas experimentales del movimiento del robot, siendo éste el único procedimiento práctico que permite la obtención de valores fiables de los mismos cuando el sistema mecánico presenta una mínima complejidad. La importancia de la identificación de parámetros dinámicos se manifiesta especialmente tanto en aplicaciones de control por dinámica inversa como en simulación dinámica. En esta tesis, se aborda la identificación de parámetros dinámicos, tanto desde el punto de vista teórico como experimental, en robots manipuladores con configuración de cadena cinemática abierta. Por una parte, se desarrolla el modelo dinámico de un robot manipulador a partir de las ecuaciones de la dinámica de acuerdo al formalismo de Gibbs-Appell. Para ello, se asume el robot constituido por barras rígidas, modelándose independientemente el comportamiento dinámico de los actuadores. Se consideran asimismo algunos modelos de fricción lineales con respecto a sus coeficientes con objeto de modelar los fenómenos de fricción en los nudos. Posteriormente, las ecuaciones que constituyen dicho modelo dinámico son reescritas de forma lineal respecto a los parámetros dinámicos a identificar y en forma matricial, a fin de permitir la posterior aplicación de técnicas numéricas tanto de análisis y reducción como de resolución del sistema de ecuaciones así constituido. Por otra parte, se tratan algunos aspectos fundamentales de la identificación de parámetros dinámicos tanto a nivel teórico como práctico. Así, se aborda la generación de trayectorias optimizadas, recurriéndose a la parametrización de las mismas mediante series finitas de Fourier, lo cual permite beneficiarse del carácter periódico de éstas. Asimismo, se propone un procedimiento para la resolución del sistema de ecuaciones mediante el cual se asegura l / Benimeli Andreu, FJ. (2005). Estimación de parámetros dinámicos en robots manipuladores [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1995

Prideparaden är kulmen för det som kallas Stockholms Pridefestival. Det är ett årligt evenemang och lockar många människor för att både delta och åskåda. Paraden är unik på så sätt att den har ett politiskt syfte som når ut genom glädje och festligheter. Syftet med denna studie har varit att undersöka och analysera hur Prideparaden har gestaltats i Svenska Dagbladets nyhetsrapportering mellan åren 1979-2018, men också hur diskursen haft en påverkan på gestaltningens förändring. Frågeställningarna behandlar vilka skillnader och likheter det finns gällande vilka ämnen som betonas och vilka aktörer som omtalas i artiklarna, samt vilken förändring vi kan se i rapporteringens gestaltning över tid rörande Prideparaden i relation till diskursen. Metoden som används är en kritisk diskursanalys, där totalt 14 artiklar analyseras. Urvalet är begränsat till artiklar som enbart rör paraden. Därefter görs en komparativ analys av resultatet. Studiens resultat visar att det finns skillnader i vilka ämnen som betonas samt vilka aktörer som får komma till tals. Gällande diskursens påverkan på framförallt rapporteringen besvaras detta genom en diskussion då det inte går att dra några generella slutsatser kring resultatet.

Kritiken och verkligheten söker utröna skillnader datorspelskritik och litteraturkritik emellan. Mina tankar rörande de två områdena kretsade till en början kring att litteraturkritiken tilläts röra sig mer fritt mellan olika kulturella sfärer medan datorspelskritiken mer hängav sig åt en yngre målgrupp utan referenser till andra kulturyttringar.   För att undersöka detta har jag gjort en diskuskursanalytisk undersökning efter van Dijks modell. Undersökningen inkluderar tolv analysenheter; tre böcker och tre spel. Varje verk har analyserats två gånger då jag analyserat recensioner från två olika tidningar (DN och SvD) för att komma än djupare i mina analyser kring hur aktuella böcker och spel behandlats. För att få spelen och böckerna något sånär jämförbara har jag ställt upp ett antal kriterier, där ett av de mer centrala är att samtliga verk har varit ett av de mest sålda verken ett givet år (2007-2009). Det är alltså "storsäljare" jag tittar på, i hopp om att de representerar de mest populära verken inom sitt fält.   För att göra denna undersökning och göra dessa jämförelser har jag utgått från Pierre Bourdieus begrepp "sociala fält" för att kunna bedöma när en recension lämnar sitt eget fält och äntrar ett annat. Detta begrepp är flexibelt så till vida att litteratur exempelvis kan anses vara ett fält, medan en nedskalning kan innebära att svensk feministlitteratur är ett annat, "mindre" fält. För att ytterligare närma mig kritikens, recensionens och värderingens värld har jag använt mig av Tomas Forser redogörelser och forskning kring vad dessa begrepp innebär. Jag har plockat ut ett antal, för uppsatsen, intressanta termer ur hans forskning för att konkretisera vissa delar av min teoretiska ram. Mina föreställningar om att litteraturartiklarna skulle inkludera långt fler referenser till andra sociala fält stämde inte helt och hållet, då vissa datorspelsartiklar var fullproppade med desamma. Däremot kom jag fram till att samtliga böcker anses säga något om verkligheten eller samhället, medan datorspelen aldrig antogs göra det.

The work deals with automatic summarization of documents in HTML format. As a language of web documents, Czech language has been chosen. The project is focused on algorithms of text summarization. The work also includes document preprocessing for summarization and conversion of text into representation suitable for summarization algorithms. General text mining is also briefly discussed but the project is mainly focused on the automatic document summarization. Two simple summarization algorithms are introduced. Then, the main attention is paid to an advanced algorithm that uses latent semantic analysis. Result of the work is a design and implementation of summarization module for Python language. Final part of the work contains evaluation of summaries generated by implemented summarization methods and their subjective comparison of the author.

La thermographie infrarouge est une méthode largement employée pour la caractérisation des propriétés thermophysiques des matériaux. L’avènement des diodes laser pratiques, peu onéreuses et aux multiples caractéristiques, étendent les possibilités métrologiques des caméras infrarouges et mettent à disposition un ensemble de nouveaux outils puissants pour la caractérisation thermique et le contrôle non desturctif. Cependant, un lot de nouvelles difficultés doit être surmonté, comme le traitement d’une grande quantité de données bruitées et la faible sensibilité de ces données aux paramètres recherchés. Cela oblige de revisiter les méthodes de traitement du signal existantes, d’adopter de nouveaux outils mathématiques sophistiqués pour la compression de données et le traitement d’informations pertinentes. Les nouvelles stratégies consistent à utiliser des transformations orthogonales du signal comme outils de compression préalable de données, de réduction et maîtrise du bruit de mesure. L’analyse de sensibilité, basée sur l’étude locale des corrélations entre les dérivées partielles du signal expérimental, complète ces nouvelles approches. L'analogie avec la théorie dans l'espace de Fourier a permis d'apporter de nouveaux éléments de réponse pour mieux cerner la «physique» des approches modales.La réponse au point source impulsionnel a été revisitée de manière numérique et expérimentale. En utilisant la séparabilité des champs de température nous avons proposé une nouvelle méthode d'inversion basée sur une double décomposition en valeurs singulières du signal expérimental. Cette méthode par rapport aux précédentes, permet de tenir compte de la diffusion bi ou tridimensionnelle et offre ainsi une meilleure exploitation du contenu spatial des images infrarouges. Des exemples numériques et expérimentaux nous ont permis de valider dans une première approche cette nouvelle méthode d'estimation pour la caractérisation de diffusivités thermiques longitudinales. Des applications dans le domaine du contrôle non destructif des matériaux sont également proposées. Une ancienne problématique qui consiste à retrouver les champs de température initiaux à partir de données bruitées a été abordée sous un nouveau jour. La nécessité de connaitre les diffusivités thermiques du matériau orthotrope et la prise en compte des transferts souvent tridimensionnels sont complexes à gérer. L'application de la double décomposition en valeurs singulières a permis d'obtenir des résultats intéressants compte tenu de la simplicité de la méthode. En effet, les méthodes modales sont basées sur des approches statistiques de traitement d'une grande quantité de données, censément plus robustes quant au bruit de mesure, comme cela a pu être observé. / Infrared thermography is a widely used method for characterization of thermophysical properties of materials. The advent of the laser diodes, which are handy, inexpensive, with a broad spectrum of characteristics, extend metrological possibilities of infrared cameras and provide a combination of new powerful tools for thermal characterization and non destructive evaluation. However, this new dynamic has also brought numerous difficulties that must be overcome, such as high volume noisy data processing and low sensitivity to estimated parameters of such data. This requires revisiting the existing methods of signal processing, adopting new sophisticated mathematical tools for data compression and processing of relevant information.New strategies consist in using orthogonal transforms of the signal as a prior data compression tools, which allow noise reduction and control over it. Correlation analysis, based on the local cerrelation study between partial derivatives of the experimental signal, completes these new strategies. A theoretical analogy in Fourier space has been performed in order to better understand the «physical» meaning of modal approaches.The response to the instantaneous point source of heat, has been revisited both numerically and experimentally. By using separable temperature fields, a new inversion technique based on a double singular value decomposition of experimental signal has been introduced. In comparison with previous methods, it takes into account two or three-dimensional heat diffusion and therefore offers a better exploitation of the spatial content of infrared images. Numerical and experimental examples have allowed us to validate in the first approach our new estimation method of longitudinal thermal diffusivities. Non destructive testing applications based on the new technique have also been introduced.An old issue, which consists in determining the initial temperature field from noisy data, has been approached in a new light. The necessity to know the thermal diffusivities of an orthotropic medium and the need to take into account often three-dimensional heat transfer, are complicated issues. The implementation of the double singular value decomposition allowed us to achieve interesting results according to its ease of use. Indeed, modal approaches are statistical methods based on high volume data processing, supposedly robust as to the measurement noise.

Humanitarian clearance of minefields is most often carried out by hand, conventionally using a a metal detector and a probe. Detection is a very slow process, as every piece of detected metal must treated as if it were a landmine and carefully probed and excavated, while many of them are not. The process can be safely sped up by use of Ground-Penetrating Radar (GPR) to image the subsurface, to verify metal detection results and safely ignore any objects which could not possibly be a landmine. In this thesis, we explore the possibility of using Full Wave Inversion (FWI) to improve GPR imaging for landmine detection. Posing the imaging task as FWI means solving the large-scale, non-linear and ill-posed optimisation problem of determining the physical parameters of the subsurface (such as electrical permittivity) which would best reproduce the data. This thesis begins by giving an overview of all the mathematical and implementational aspects of FWI, so as to provide an informative text for both mathematicians (perhaps already familiar with other inverse problems) wanting to contribute to the mine detection problem, as well as a wider engineering audience (perhaps already working on GPR or mine detection) interested in the mathematical study of inverse problems and FWI.We present the first numerical 3D FWI results for GPR, and consider only surface measurements from small-scale arrays as these are suitable for our application. The FWI problem requires an accurate forward model to simulate GPR data, for which we use a hybrid finite-element boundary-integral solver utilising first order curl-conforming N\'d\'{e}lec (edge) elements. We present a novel `line search' type algorithm which prioritises inversion of some target parameters in a region of interest (ROI), with the update outside of the area defined implicitly as a function of the target parameters. This is particularly applicable to the mine detection problem, in which we wish to know more about some detected metallic objects, but are not interested in the surrounding medium. We may need to resolve the surrounding area though, in order to account for the target being obscured and multiple scattering in a highly cluttered subsurface. We focus particularly on spatial sensitivity of the inverse problem, using both a singular value decomposition to analyse the Jacobian matrix, as well as an asymptotic expansion involving polarization tensors describing the perturbation of electric field due to small objects. The latter allows us to extend the current theory of sensitivity in for acoustic FWI, based on the Born approximation, to better understand how polarization plays a role in the 3D electromagnetic inverse problem. Based on this asymptotic approximation, we derive a novel approximation to the diagonals of the Hessian matrix which can be used to pre-condition the GPR FWI problem.

This thesis introduces a multilinear algebraic framework for computer graphics, computer vision, and machine learning, particularly for the fundamental purposes of image synthesis, analysis, and recognition. Natural images result from the multifactor interaction between the imaging process, the scene illumination, and the scene geometry. We assert that a principled mathematical approach to disentangling and explicitly representing these causal factors, which are essential to image formation, is through numerical multilinear algebra, the algebra of higher-order tensors. Our new image modeling framework is based on(i) a multilinear generalization of principal components analysis (PCA), (ii) a novel multilinear generalization of independent components analysis (ICA), and (iii) a multilinear projection for use in recognition that maps images to the multiple causal factor spaces associated with their formation. Multilinear PCA employs a tensor extension of the conventional matrix singular value decomposition (SVD), known as the M-mode SVD, while our multilinear ICA method involves an analogous M-mode ICA algorithm. As applications of our tensor framework, we tackle important problems in computer graphics, computer vision, and pattern recognition; in particular, (i) image-based rendering, specifically introducing the multilinear synthesis of images of textured surfaces under varying view and illumination conditions, a new technique that we call ``TensorTextures'', as well as (ii) the multilinear analysis and recognition of facial images under variable face shape, view, and illumination conditions, a new technique that we call ``TensorFaces''. In developing these applications, we introduce a multilinear image-based rendering algorithm and a multilinear appearance-based recognition algorithm. As a final, non-image-based application of our framework, we consider the analysis, synthesis and recognition of human motion data using multilinear methods, introducing a new technique that we call ``Human Motion Signatures''.

This thesis introduces a multilinear algebraic framework for computer graphics, computer vision, and machine learning, particularly for the fundamental purposes of image synthesis, analysis, and recognition. Natural images result from the multifactor interaction between the imaging process, the scene illumination, and the scene geometry. We assert that a principled mathematical approach to disentangling and explicitly representing these causal factors, which are essential to image formation, is through numerical multilinear algebra, the algebra of higher-order tensors. Our new image modeling framework is based on(i) a multilinear generalization of principal components analysis (PCA), (ii) a novel multilinear generalization of independent components analysis (ICA), and (iii) a multilinear projection for use in recognition that maps images to the multiple causal factor spaces associated with their formation. Multilinear PCA employs a tensor extension of the conventional matrix singular value decomposition (SVD), known as the M-mode SVD, while our multilinear ICA method involves an analogous M-mode ICA algorithm. As applications of our tensor framework, we tackle important problems in computer graphics, computer vision, and pattern recognition; in particular, (i) image-based rendering, specifically introducing the multilinear synthesis of images of textured surfaces under varying view and illumination conditions, a new technique that we call ``TensorTextures'', as well as (ii) the multilinear analysis and recognition of facial images under variable face shape, view, and illumination conditions, a new technique that we call ``TensorFaces''. In developing these applications, we introduce a multilinear image-based rendering algorithm and a multilinear appearance-based recognition algorithm. As a final, non-image-based application of our framework, we consider the analysis, synthesis and recognition of human motion data using multilinear methods, introducing a new technique that we call ``Human Motion Signatures''.