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Hong, Quanhua Claire. "SAR processing direct spectrum formation and image reconstruction /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0004/MQ42575.pdf.
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Sanders, James Henry. "Direct stochastic optical reconstruction microscopy (dSTORM) imaging of cellular structures." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/direct-stochastic-optical-reconstruction-microscopy-dstorm-imaging-of-cellular-structures(915e2c88-c81a-4b24-ac53-6ab7ffcbf4d8).html.
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The diffraction limit restricts conventional light microscopes to approximately 250 nm laterally and 500 nm axially, these limits being first proposed by Abbe in 1873. Despite this, optical microscopes have found many applications in biological research and single cells that are 10 - 100 um in size. Furthermore by coupling the non-invasive nature of a light microscope with highly sensitive fluorescent probes, fluorescence microscopy has also become a standard imaging technique. Recent advances in fluorescence microscopy now provide a number of methods to circumvent the Abbe diffraction limit, with many techniques becoming prevalent over the last 10 years including direct Stochastic Optical Reconstruction Microscopy (dSTORM). A dSTORM system has been constructed and calibrated using a commercially available inverted florescence microscope and total internal reflection florescence (TIRF) imaging. dSTORM relies on the ability to switch sparse subsets of fluorophores and temporally separate them. Provided the spatial separation is sufficient between any member of a subset, the average error with which the emission can be localized is much less than size of the emission profile itself. The underlying mechanism for this switching is detailed based on the principle of photoinduced electron transfer (PET). The switching characteristics of the common florescent dye Alexa Fluor 568 are investigated and shown to be controlled by a number of factors including the excitation intensity and concentration of the primary thiol cysteamine beta-MEA. A number of parameters are defined, including the dye switching rate, for a given set of physical parameters. U2OS cells are labelled for the microtubule protein Tubulin using immunofluorescent labelling strategies. A direct comparison is made between diffraction limited TIRF images and dSTORM reconstructed images, with an average width for microtubules determined to (58.2 ± 8.1) nm. Further measurements are made by labelling the Rab5 effector Early Endosome Antigen 1 (EEA1). From this the aspect ratio for early endosomes is determined to be 1.68 ± 0.7 with an average radius of (45.8 ± 18.8) nm. The point spatial distribution of EEA1 is investigated by using the linearised form of Ripley's K-function H(r) and the null hypothesis of complete spatial randomness tested. EEA1 is shown to cluster at radius of 58.7 nm on individual endosomes, thought to be due to the well defined binding domains present on early endosomes for EEA1. Further evidence suggests that clustering is also exhibited at another maximum of approximately 500 nm when looking at an ensemble of EEA1 and early endosomes.
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Khomutenko, Bogdan. "Contribution à la Perception Visuelle Basée Caméras Grand Angle pour la Robotique Mobile et Les Véhicules Autonomes." Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0010/document.
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Ce travail de thèse présente un nouveau modèle de projection pour les cameras fisheye, qui est mathématiquement simple et pourtant montre une haute précision une fois appliqué aux caméras réelles. Les propriétés géométriques de ce modèle ont été analysées en utilisant le concept de surface de projection, introduit dans ce travail. En particulier, une inverse analytique de ce modèle a été établie, ainsi qu'une équation implicite des projections de lignes droites. Cette dernière nous a permis de développer une méthode de reconstruction 3D directe basée vision pour les caméras fisheye sans rectifier les images. Cela a été fait grâce à une algorithme de rastérisation de courbes implicites. Cet algorithme de reconstruction nous permet d'employer le Semi-Global Matching pour obtenir une reconstruction 3D précise. Tous ces éléments ont été employés dans un système de localisation visuelle directe avec deux méthodes de recalage d'images : minimisation d'erreur photométrique et maximisation d'information mutuelle. L'étalonnage intrinsèque et extrinsèque d'un robot mobile équipé de caméras fisheye a été considéré et une toolbox d'étalonnage a été développéeThis thesis presents a novel projection model for fisheye cameras, which is mathematically simple and yet shows a high precision when applied to real cameras. Geometric properties of the model have been analyzed using the concept of projection surface, introduced in this work. In particular, a closed-form inverse mapping and an implicit equation for straight line projection have been found. This fact has been used to develop a method of direct stereo correspondence on raw fisheye images via rasterization of implicit curve. This correspondence algorithm allows us to apply the Semi-Global Matching algorithm to get an accurate 3D reconstruction using fisheye stereo systems. All these elements have been shown to be applicable to a direct visual localization system with two different methods of image registration: direct photometric error minimization and mutual information maximization. Intrinsic and extrinsic calibration of a mobile robot with fisheye cameras has been considered and a toolbox for such a calibration has been developed
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Lampe, André [Verfasser]. "Three dimensional multicolor direct Stochastic Optical Reconstruction Microscopy and Applications in Membrane Biochemistry / André Lampe." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1126645931/34.
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Qi, Yusheng Ph D. Massachusetts Institute of Technology. "Phase-resolved reconstruction and forecast of nonlinear irregular wave field based on direct numerical simulations." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111739.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 241-249).
The problem of phase-resolved reconstruction and forecast of ocean wave field based on measurements is of basic scientific interest and practical importance in ocean science and marine engineering. This capability aids and expands the use and interpretation of field and wave basin measurements, contributing to the study of fundamental wave mechanics. It also expands the operational envelope and improves survivability and efficiency of ships and marine facilities in severe seas. We develop theoretical and computational capabilities to solve this problem, which can be applied to both ocean wave field and wave basin experiments. Given limited wave measurement data, there exists specific space and time domain( s) (the "predictable zone") where the wave-field can be reconstructed and forecasted. In this thesis, using linearized wave theory and reasonable assumptions of the frequency and directional extent of the wave field, we obtain closed-form expressions for (linear) predictable zone PL in terms of set notation involving the individual measurement. We derive and illustrate PL obtained for ("probe") measurements at one or more fixed locations over time, for moving probes, for whole-area wave measurements, and combinations of these. We also consider the problem of optimal deployment of these measurements to maximize the volume of PL in space-time. For J probes, we show that this volume scales as J³ (in contrast to J when the predictable zones of individual measurements are simply summed). With the knowledge of the predictable zone, we develop and validate a high-order reconstruction (HOR) method for the phase-resolved reconstruction of nonlinear wave field given a set of wave measurements. HOR optimizes the amplitude and phase of L free-wave components of the nonlinear wave field, accounting for nonlinear wave interactions up to order M in the evolution to obtain a nonlinear wave field that minimizes the reconstruction error between reconstructed wave field and the given measurements. For a given reconstruction tolerance, L and M are provided in the HOR scheme itself. To demonstrate the validity and efficacy of HOR, we perform extensive tests of general two- and three-dimensional wave fields specified by theoretical Stokes waves, nonlinear simulations, and physical wave fields in tank experiments. The necessary L, for general broad banded wave fields, is shown to be relatively small and substantially less than the free and locked modes needed for the nonlinear evolution. We find that, even for relatively small wave steepness, the inclusion of high-order effects in HOR is important for prediction of wave kinematics not in the measurements. For all the cases we consider, HOR converges to the underlying wave field within a nonlinear spatial-temporal predictable zone PNL (dependent on the measurements and wave nonlinearity). PNL generally extends in time (and space) beyond the measurements, thus obtaining reliable forecast/predictions of the wave field. For linear waves, PNL=PL, verifying the predictable zone theory. With increasing wave nonlinearity, we show that PNL contains and is generally greater than PL. Thus PL provides a (conservative) estimate of PNL when the underlying wave field is not known. For nonlinear steep wave-field, wave breaking plays an important role in the evolution of the wave field. We develop a phenomenological wave breaking model that can be incorporated into the nonlinear evolution engine of HOR to predict breaking onset and simulate proper amount of energy dissipation. Thus HOR can properly reconstruct and forecast nonlinear wave field which may contain breaking events. The breaking model is developed in the spectra domain and based on analysis of simulated two-dimensional wave breaking caused by different wave-wave interaction mechanism, including modulation instability and wave focusing. The developed wave breaking model is calibrated, validated and verified by different wave breaking measurements and excellent agreement is obtained between simulated wave breaking results and measured ones. The wave breaking model can be further used to simulate the locations of breaking events, which is validated statistically by calculating the Phillips statistics. This thesis does not address the issue of wave-body interaction nor the control problem for scale models in the wave basin, but it provides necessary nonlinear whole-field data for intense CFD analysis of wave-body interaction at a level heretofore not possible. The presence of imposed current or wind is not considered at this stage but can be incorporated in the future using the same framework.
by Yusheng Qi.
Ph. D.
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Thomas, Julie Eleanor. "A determination of the W boson mass by direct reconstruction using the DELPHI detector at LEPII." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299387.
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Vanco, Marek. "A Direct Approach for the Segmentation of Unorganized Points and Recognition of Simple Algebraic Surfaces." Doctoral thesis, Universitätsbibliothek Chemnitz, 2003. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200300486.
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In Reverse Engineering a physical object is digitally reconstructed from a set of boundary points. In the segmentation phase these points are grouped into subsets to facilitate consecutive steps as surface fitting. In this thesis we present a segmentation method with subsequent classification of simple algebraic surfaces. Our method is direct in the sense that it operates directly on the point set in contrast to other approaches that are based on a triangulation of the data set. The reconstruction process involves a fast algorithm for $k$-nearest neighbors search and an estimation of first and second order surface properties. The first order segmentation, that is based on normal vectors, provides an initial subdivision of the surface and detects sharp edges as well as flat or highly curved areas. One of the main features of our method is to proceed by alternating the steps of segmentation and normal vector estimation. The second order segmentation subdivides the surface according to principal curvatures and provides a sufficient foundation for the classification of simple algebraic surfaces. If the boundary of the original object contains such surfaces the segmentation is optimized based on the result of a surface fitting procedureIm Reverse Engineering wird ein existierendes Objekt aus einer Menge von Oberflächenpunkten digital rekonstruiert. Während der Segmentierungsphase werden diese Punkte in Teilmengen zusammengefügt, um die nachfolgenden Schritte wie Flächenerkennung (surface fitting) zu vereinfachen. Wir präsentieren in dieser Arbeit eine Methode zur Segmentierung der Punkte und die anschließende Klassifikation einfacher algebraischen Flächen. Unser Verfahren ist direkt in dem Sinne, dass es direkt an den Punkten arbeitet, im Gegensatz zu anderen Verfahren, die auf einer Triangulierung der Punktmenge basieren. Der Rekonstruktionsprozess schließt einen neuen Algorithmus zur Berechnung der k-nächsten Nachbarn eines Oberflächenpunktes und Verfahren zur Schätzung der Flächeneigenschaften ersten und zweiten Grades ein. Die normalenbasierte Segmentierung (Segmentierung ersten Grades) liefert eine Aufteilung des Objektes und detekiert scharfe Kanten, sowie flache oder stark gekrümmte Gebiete des Objektes. Ein zentrales Element unserer Methode ist die Wiederholung der Schritte der Segmentierung und der Schätzung der Normalen. Erst die Iteration ermöglicht die Schätzung der Normalen in der benötigten Genauigkeit und die Generierung einer zufriedenstellender Segmentierung. Die Segmentierung zweiten Grades teilt die Oberfläche nach den Hauptkrümmungen auf und bietet eine zuverlässige Grundlage für die Klassifizierung einfacher algebraischen Flächen. Falls der Rand des Ausgangsobjektes solche Flächen enthält, wird der Segmentierungsprozess auf der Grundlage des Ergebnisses der Flächenerkennungsprozedur optimiert
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Khalil, Ali Moussa. "European business interests in Lebanon : an assessment of EU private foreign direct investment in the reconstruction era." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4248/.
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The flow of foreign direct investment has long been regarded as the main engine of growth in developing countries. Lebanon has aimed at attracting foreign direct investment to contribute to its economic recovery in the post-civil war period. EU countries were expected to be a major source of investment inflows, partly, due to their rich historical relationship, and partly, as an expected result of the new Euro-Med approach, adopted in the 1990s.This thesis assesses the EU private business interests in Lebanon during the reconstruction period, and investigates to what extent EU business engagements involved FDI. Within this framework, this thesis examines the role of the EU in encouraging the flow of EU private investments into Lebanon. This thesis falls into two parts. The first assesses the history of economic relations between Lebanon and Europe in the modern period, and the development of these relations after the establishment of the EC, examining the role of the latter in reshaping these relations. It also assesses the development of the Lebanese economy since independence from France. In the second part of the thesis, the theoretical framework of FDI is applied to a survey of EU private businesses operating in Lebanon. This helped in answering two questions: what business activities did involve FDI, and why EU firms engagement in FDI was very shallow. The thesis concludes that the lack of FDI activities in Lebanon, whether EU or non-EU, was a result of the lack of comparative location-specific advantages. It also suggests that the Lebanese government should assume a stronger role in improving Lebanon’s comparative advantages in order to attract FDI. The EU should provide substantial help - within the Euro-Med approach - to encourage EU private business investments in the country.
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Trillon, Adrien. "Reconstruction de défauts à partir de données issues de capteurs à courants de Foucault avec modèle direct différentiel." Phd thesis, Ecole centrale de nantes - ECN, 2010. http://tel.archives-ouvertes.fr/tel-00700739.
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La tomographie par courants de Foucault peut être utilisée pour évaluer la forme et le volume de défauts dans des plaques métalliques de générateur de vapeur de centrale nucléaire. L'objectif du travail présenté est de cartographier la distribution d'une grandeur représentative du défaut, ici la conductivité relative. Ce problème est difficile à résoudre car mal-posé et non-linéaire. Afin de le résoudre un modèle numérique est nécessaire. Nos travaux ont tout d'abord consisté à étudier les modèles directs existants pour choisir le plus adapté à notre cas. Il s'est avéré que les méthodes différentielles, différences finies ou éléments finis, étaient les plus adaptées à notre cas. Une fois que le modèle direct a été choisi, nous avons adapté les méthodes de type contrast source inversion (CSI) à ce modèle, puis proposé un nouveau critère à minimiser. Les méthodes de type CSI sont basées sur la minimisation de l'erreur quadratique pondérée des équations du modèle, observation et couplage. Par construction, elles autorisent une erreur sur ces équations. Il apparaît que les résultats de reconstruction s'améliorent lorsque l'erreur sur l'équation de couplage diminue. Afin de contraindre cette équation en évitant des problèmes de conditionnement, on a eu recours à une technique de Lagrangien augmenté. Enfin, le caractère mal-posé de ce problème peut être contourné en introduisant des informations a priori adéquates notamment sur la forme générale des défauts à reconstruire ainsi que sur les valeurs possibles de la conductivité relative. L'efficacité des méthodes développées est illustrée avec des cas simulés en 2D.
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Lemay-Hébert, Nicolas. "State-building from the outside-in : international administrations and the perils of direct governance." Paris, Institut d'études politiques, 2009. http://www.theses.fr/2009IEPP0046.
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La gouvernance directe par une administration internationale tend à créer une vague contestation locale au state-building conduit de l'extérieur. Dans ce contexte, nos recherches au Kosovo et au Timor-Leste démontrent que la réponse politique, soit la gouvernance directe des "États effondrés", ne semble pas à même de répondre aux défis sociaux posés par la reconstruction des capacités étatiques dans un contexte post-conflit. En d'autres mots, la gouvernance directe par une administration internationale est difficilement compatible avec l'objectif de créer et d'assurer la légitimité d'un projet de state-building conduit de l'extérieur. Si les aspects propres à la légitimité sont initialement mis de côté lors de la conception de la mission et la conduite du state-building sur le terrain, ils tendent néanmoins à réaffirmer leur présence et leur importance au cours de l'intervention. Que ce soit au Kosovo ou au Timor-Leste, l'ONU s'est rapidement retrouvée conronté à une crise de légitimité quant à sa présence sur le terrain. En effet, la légitimité initiale de l'intervention et de l'intervenant s'est rapidement évanouie avec l'exercise du mandat d'administration directe sur le terrain. La contestation sans précédents des acteurs locaux sur le terrain n'a d'égal que le niveau d'autorité effective exercée par l'administration internationale. Cette étude a démontré notamment que le Kosovo et le Timor-Leste représentent des tentatives sans précédents de state-building international, notamment en ce qui a trait à l'autorité déployée sur le terrain par l'acteur international. Dans ce contexte, certains mécanismes de responsabilisation de l'intervenant s'avèrent nécessairesDirect governance by an international administration tends to create a social backlash in a state-building context. In this regard, the contemporary international administration seems directly related to the mainstream conception of the state, state collapse and state-building. The political response, namely direct governance of “collapsed states,” seems unfit to correctly address the social challenges of postwar state-building. In other words, direct governance of war-torn territories is hardly compatible with the objective of fostering and nurturing legitimacy in an externally-led state-building project. The legitimacy aspects pertaining to state-building, if initially discarded in the setting-up and exercise of the peace mission’s mandate, will find a way to reaffirm themselves throughout the mission. In Kosovo as in Timor-Leste, the UN found itself embroiled in a deep legitimacy crises. Indeed, the missions’ legitimacy quickly withered away with the actual exercise of authority by the mission. The unprecedented contestation and resistance to the UN found in Kosovo and Timor-Leste is correlated with the equally unprecedented level of authority endowed to the peace mission, which translated into direct governance of the territories. This study has demonstrated that both Kosovo and Timor-Leste represent truly unprecedented attempts of state-building, not because of their mandate, but, more importantly, because their mandate has been translated into effective authority on the ground. In this context, accountability mechanisms can be instrumental in assuring a certain degree of trust between the international presence and the local population
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Abulaiti, Yiming. "Search for Direct Top Squark Pair Production with the ATLAS Experiment and Studies of the Primary Vertex Reconstruction Performance." Licentiate thesis, Stockholms universitet, Fysikum, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-105746.
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The ATLAS detector is one of the two largest experiments installed at the Large Hadron Collider at CERN, the European Organization for Nuclear Research. During the first run, the ATLAS detector recorded data at centre of mass energies of 7 TeV and 8 TeV, enabling many precision measurements and new physics searches. One important task in ATLAS is measuring the primary vertex, the interaction point of the hardest proton-proton collision in an event. In this thesis, a study of the primary vertex reconstruction performance in data and simulated events using $t\bar{t}$ and ${Z}$ events is presented. Within the statistics available, the performance in data and simulated events is found to be compatible. Motivated by the limitations of the Standard Model of particle physics, searches for supersymmetric particles are performed with the ATLAS experiment. No signal has been observed so far, and the results are used to set exclusion limits on the masses of the supersymmetric particles. As the exclusion limits are derived from analyses which each target only a single decay mode of a supersymmetric particle, the analyses might have lower sensitivity to more complex decay scenarios. In this thesis the sensitivity of one of the ATLAS searches for direct top squark pair production to models with more complex decay modes is investigated. The study concludes that the sensitivity to models where the top squark can decay via heavier charginos and neutralinos is lower than the sensitivity to models where only decays to the lightest chargino or neutralino are present.
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Zhou, Qiping. "Near-field microwave imaging with coherent and interferometric reconstruction methods." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1591903415194694.
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Moon, Thomas. "Testing and characterization of high-speed signals using incoherent undersampling driven signal reconstruction algorithms." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54326.
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The objective of the proposed research is to develop a framework for the signal reconstruction algorithm with sub-Nyquist sampling rate and the low-cost hardware design in system level. A further objective of the proposed research is to monitor the device-under-test (DUT) and to adapt its behaviors. The key contribution of this research is that the high-speed signal acquisition is done by direct subsampling. As the signal is directly sampled without any front-end radio-frequency (RF) components such as mixers or filters, the cost of hardware is reduced. Furthermore, the distortion and the nonlinearity from the RF components can be avoided. The first proposed work is wideband signal reconstruction by dual-rate time-interleaved subsampling hardware and Multi-coset signal reconstruction. Using the combination of the dual-rate hardware and the multi-coset algorithm, the number of sampling channel is significantly reduced compared to the conventional multi-coset works. The second proposed work is jitter tracking by accurate period estimation with incoherent subsampling. In this work, the long-term jitter in PRBS is tracked without hardware synchronization and clock-data-recovery (CDR) circuits. The third proposed work is eye-monitoring and time-domain-reflectometry (TDR) by monobit receiver signal reconstruction. Using a monobit receiver based on incoherent subsampling and time-variant threshold signal, high resolution of reconstructed signal in both amplitude and time is achieved. Compared to a multibit-receiver, the scalability of the test-system is significantly increased.
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Šumanovac, Šestak Ivana [Verfasser], Rainer [Gutachter] Heintzmann, and Thomas [Gutachter] Cremer. "High-resolution direct stochastic optical reconstruction microscopy of the human kinetochore chromatin / Ivana Šumanovac Šestak ; Gutachter: Rainer Heintzmann, Thomas Cremer." Jena : Friedrich-Schiller-Universität Jena, 2020. http://d-nb.info/1225298423/34.
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Engel, Jakob-Julian [Verfasser], Daniel [Akademischer Betreuer] Cremers, Daniel [Gutachter] Cremers, and Andrew [Gutachter] Davison. "Large-Scale Direct SLAM and 3D Reconstruction in Real-Time / Jakob-Julian Engel ; Gutachter: Daniel Cremers, Andrew Davison ; Betreuer: Daniel Cremers." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/1149824174/34.
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Gaullier, Gil. "Modèles déformables contraints en reconstruction d'images de tomographie non linéaire par temps d'arrivée." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAD026/document.
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La reconstruction tomographique par temps de première arrivée est rendue difficile par son caractère mal posé et par la non-linéarité du problème direct associé. Dans cette thèse, on se propose d'employer un modèle déformable, permettant d'introduire un a priori global sur la forme des objets à reconstruire, pour obtenir des solutions plus stables et de meilleure qualité. Dans un premier temps, nous introduisons des contraintes de forme de haut niveau en reconstruction tomographique d'émission, modalité où le problème direct est linéaire. Dans un second temps, différentes stratégies de résolution du problème non linéaire de reconstruction en temps d'arrivée sont envisagées. La solution retenue approche le problème direct par une suite de problèmes linéaires, conduisant à un algorithme par minimisations successives simples, au coursdesquelles l'a priori de forme est introduit. L'efficacité de la méthode est montrée en simulation et à partir de données réelles, acquises sur un banc développé par l'IFSTTAR pour le contrôle non destructif de structures de génie civilImage reconstruction from first time arrival is a difficult task due to its ill-posedness nature and to the non linearity of the direct problem associated. In this thesis, the purpose is to use a deformable model because it enables to introduce a global shape prior on the objects to reconstruct, which leads to more stable solutions with better quality. First, high level shape constraints are introduced in Computerized Tomography for which the direct problem is linear. Secondly, different strategies to solve the image reconstruction problem with a non linearity hypothesis are considered. The chosen strategy approximates the direct problem by a series of linear problems, which leads to a simple successive minimization algorithm with the introduction of the shape prior along the minimization. The efficiency of the method is demonstrated for simulated data as for real data obtained from a specific measurement device developped by IFSTTAR for non destructive evaluation of civil engineering structures
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Maksymenko, Kostiantyn. "Nouvelles approches algorithmiques pour les problèmes directs et inverses en M/EEG." Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4112.
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La Magnéto- et l'Electro-encéphalographie (M/EEG) sont deux modalités d'imagerie fonctionnelle non invasives qui mesurent l'activité électromagnétique du cerveau. Ces techniques sont utilisées pour des études cognitives ainsi que pour des applications cliniques, comme l'épilepsie. Après une présentation de quelques notions de base sur ces modalités M/EEG, cette thèse développe deux contributions principales. La première est une méthode d’approximation efficace d’un ensemble de solutions de problèmes directs d’EEG paramétrés par des valeurs de conductivité pour différents tissus. Ce problème direct consiste à calculer comment une activité corticale spécifique serait mesurée par des capteurs EEG. Le principal avantage de notre méthode est qu’elle accélère considérablement le temps de calcul tout en contrôlant l'erreur d'approximation. Les valeurs de conductivités des tissus de la tête varient selon les sujets et il serait intéressant de les estimer à partir des données EEG. Notre méthode est un pas important pour la résolution efficace d'un tel problème d'estimation de conductivités. La deuxième contribution est une nouvelle méthode de reconstruction de sources qui estime des configurations de sources corticales étendues expliquant les mesures M/EEG. La principale originalité de cette méthode réside dans le fait qu’au lieu de fournir une reconstruction unique, comme le font la majorité des méthodes de l’état de l'art, elle propose plusieurs solutions candidates valables. Nous avons validé nos deux contributions sur des données M/EEG simulées et réellesMagneto- and Electro-encephalography (M/EEG) are two non-invasive functional imaging modalities which measure the electromagnetic activity of the brain. These tools are used in cognitive studies as well as in clinical applications as, for example, epilepsy. Besides the presentation of some background material about the M/EEG modalities, this thesis describes two main contributions. The first one is a method for a fast approximation of a set of EEG forward problem solutions, parametrized by tissue conductivity values. This forward problem consists in computing how a specific cortical activity would be measured by EEG sensors. The main advantage of our method is that it significantly accelerates the computation time, while controlling the approximation error. Head tissue conductivity values vary across subjects and it might be interesting to estimate them from the EEG data. Our method is an important step towards an efficient solution of such a head tissues conductivity estimation problem. The second contribution is a novel source reconstruction method, which estimates extended cortical sources explaining the M/EEG measurements. The main originality of the method is that instead of providing a unique reconstruction, as the majority of the state-of-the-art methods do, it proposes several equally valid candidates. We validated both our contributions on simulated and real M/EEG data
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Lau, Wai-ping, and 劉偉平. "Direct determination of the 6H-SiC(0001)-3X3 and 6H-Sic(0001)-[square root] 3 x [square root] 3 surface reconstruction by LEED Pattersonfunction." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31367847.
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Ruff, Edward Clark III. "Electro-Optic Range Signatures of Canonical Targets Using Direct Detection LIDAR." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1522922373060272.
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Lau, Wai-ping. "Direct determination of the 6H-SiC(0001)-3X3 and 6H-Sic(0001)-[square root] 3 x [square root] 3 surface reconstruction by LEED Patterson function." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31367847.
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Hadj-Youcef, Mohamed Elamine. "Spatio spectral reconstruction from low resolution multispectral data : application to the Mid-Infrared instrument of the James Webb Space Telescope." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS326/document.
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Cette thèse traite un problème inverse en astronomie. L’objectif est de reconstruire un objet 2D+λ, ayant une distribution spatiale et spectrale, à partir d’un ensemble de données multispectrales de basse résolution fournies par l’imageur MIRI (Mid-InfraRed Instrument), qui est à bord du prochain télescope spatial James Webb Space Telescope (JWST). Les données multispectrales observées souffrent d’un flou spatial qui dépend de la longueur d’onde. Cet effet est dû à la convolution par la réponse optique (PSF). De plus, les données multi-spectrales souffrent également d’une sévère dégradation spectrale en raison du filtrage spectral et de l’intégration par le détecteur sur de larges bandes. La reconstruction de l’objet original est un problème mal posé en raison du manque important d’informations spectrales dans l’ensemble de données multispectrales. La difficulté se pose alors dans le choix d’une représentation de l’objet permettant la reconstruction de l’information spectrale. Un modèle classique utilisé jusqu’à présent considère une PSF invariante spectralement par bande, ce qui néglige la variation spectrale de la PSF. Cependant, ce modèle simpliste convient que dans le cas d’instrument à une bande spectrale très étroite, ce qui n’est pas le cas pour l’imageur de MIRI. Notre approche consiste à développer une méthode pour l’inversion qui se résume en quatre étapes : (1) concevoir un modèle de l’instrument reproduisant les données multispectrales observées, (2) proposer un modèle adapté pour représenter l’objet à reconstruire, (3) exploiter conjointement l’ensemble des données multispectrales, et enfin (4) développer une méthode de reconstruction basée sur la régularisation en introduisant des priori à la solution. Les résultats de reconstruction d’objets spatio-spectral à partir de neuf images multispectrales simulées de l’imageur de MIRI montrent une augmentation significative des résolutions spatiale et spectrale de l’objet par rapport à des méthodes conventionnelles. L’objet reconstruit montre l’effet de débruitage et de déconvolution des données multispectrales. Nous avons obtenu une erreur relative n’excédant pas 5% à 30 dB et un temps d’exécution de 1 seconde pour l’algorithme de norm-l₂ et 20 secondes avec 50 itérations pour l’algorithme norm-l₂/l₁. C’est 10 fois plus rapide que la solution itérative calculée par l’algorithme de gradient conjuguéThis thesis deals with an inverse problem in astronomy. The objective is to reconstruct a spatio-spectral object, having spatial and spectral distributions, from a set of low-resolution multispectral data taken by the imager MIRI (Mid-InfraRed Instrument), which is on board the next space telescope James Webb Space Telescope (JWST). The observed multispectral data suffers from a spatial blur that varies according to the wavelength due to the spatial convolution with a shift-variant optical response (PSF). In addition the multispectral data also suffers from severe spectral degradations because of the spectral filtering and the integration by the detector over broad bands. The reconstruction of the original object is an ill-posed problem because of the severe lack of spectral information in the multispectral dataset. The difficulty then arises in choosing a representation of the object that allows the reconstruction of this spectral information. A common model used so far considers a spectral shift-invariant PSF per band, which neglects the spectral variation of the PSF. This simplistic model is only suitable for instruments with a narrow spectral band, which is not the case for the imager of MIRI. Our approach consists of developing an inverse problem framework that is summarized in four steps: (1) designing an instrument model that reproduces the observed multispectral data, (2) proposing an adapted model to represent the sought object, (3) exploiting all multispectral dataset jointly, and finally (4) developing a reconstruction method based on regularization methods by enforcing prior information to the solution. The overall reconstruction results obtained on simulated data of the JWST/MIRI imager show a significant increase of spatial and spectral resolutions of the reconstructed object compared to conventional methods. The reconstructed object shows a clear denoising and deconvolution of the multispectral data. We obtained a relative error below 5% at 30 dB, and an execution time of 1 second for the l₂-norm algorithm and 20 seconds (with 50 iterations) for the l₂/l₁-norm algorithm. This is 10 times faster than the iterative solution computed by conjugate gradients
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Záleský, Radek. "Srovnání vybraných způsobů ocenění pro nemovitost typu byt v městské části Brno-Líšeň." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241352.
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This diploma thesis deals with the valuation of the four residential units in three model situations – without reconstruction, with partial reconstruction and with complete reconstruction. The valuation is done in three selected ways – cost and comparative method by price prescription and method of direct comparison. Is determined the usual price and described and analyzed real estated market in the location. A conclusion of this work is analyzed evaluating the investment in reconstruction and usability of coefficient of condition and equipment.
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Bae, Hyojoon. "Fast and Scalable Structure-from-Motion for High-precision Mobile Augmented Reality Systems." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/47679.
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A key problem in mobile computing is providing people access to necessary cyber-information associated with their surrounding physical objects. Mobile augmented reality is one of the emerging techniques that address this key problem by allowing users to see the cyber-information associated with real-world physical objects by overlaying that cyber-information on the physical objects's imagery. As a consequence, many mobile augmented reality approaches have been proposed to identify and visualize relevant cyber-information on users' mobile devices by intelligently interpreting users' positions and orientations in 3D and their associated surroundings. However, existing approaches for mobile augmented reality primarily rely on Radio Frequency (RF) based location tracking technologies (e.g., Global Positioning Systems or Wireless Local Area Networks), which typically do not provide sufficient precision in RF-denied areas or require additional hardware and custom mobile devices.
To remove the dependency on external location tracking technologies, this dissertation presents a new vision-based context-aware approach for mobile augmented reality that allows users to query and access semantically-rich 3D cyber-information related to real-world physical objects and see it precisely overlaid on top of imagery of the associated physical objects. The approach does not require any RF-based location tracking modules, external hardware attachments on the mobile devices, and/or optical/fiducial markers for localizing a user's position. Rather, the user's 3D location and orientation are automatically and purely derived by comparing images from the user's mobile device to a 3D point cloud model generated from a set of pre-collected photographs.
A further challenge of mobile augmented reality is creating 3D cyber-information and associating it with real-world physical objects, especially using the limited 2D user interfaces in standard mobile devices. To address this challenge, this research provides a new image-based 3D cyber-physical content authoring method designed specifically for the limited screen sizes and capabilities of commodity mobile devices. This new approach does not only provide a method for creating 3D cyber-information with standard mobile devices, but also provides an automatic association of user-driven cyber-information with real-world physical objects in 3D.
Finally, a key challenge of scalability for mobile augmented reality is addressed in this dissertation. In general, mobile augmented reality is required to work regardless of users' location and environment, in terms of physical scale, such as size of objects, and in terms of cyber-information scale, such as total number of cyber-information entities associated with physical objects. However, many existing approaches for mobile augmented reality have mainly tested their approaches on limited real-world use-cases and have challenges in scaling their approaches. By designing fast direct 2D-to-3D matching algorithms for localization, as well as applying caching scheme, the proposed research consistently supports near real-time localization and information association regardless of users' location, size of physical objects, and number of cyber-physical information items.
To realize all of these research objectives, five research methods are developed and validated: 1) Hybrid 4-Dimensional Augmented Reality (HD4AR), 2) Plane transformation based 3D cyber-physical content authoring from a single 2D image, 3) Cached k-d tree generation for fast direct 2D-to-3D matching, 4) double-stage matching algorithm with a single indexed k-d tree, and 5) K-means Clustering of 3D physical models with geo-information. After discussing each solution with technical details, the perceived benefits and limitations of the research are discussed with validation results.Ph. D.
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Lei, Ming. "Imagerie 3D d'impédance bioélectrique : problème direct, problème inverse : détermination des lignes de courant en 3D et application de la méthode de la matrice de sensibilité pour la reconstruction d'une image en 3D dans un volume conducteur inhomogène sphérique." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT010H.
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L'utilisation du courant electrique a des fins therapeutiques est une technique tres repandue en milieu medical, mais les mecanismes d'action du courant electrique dans le corps humain posent des problemes tres complexes. Ce travail cherche a apporter une contribution a une meilleure connaissance de ces mecanismes en analysant la distribution des densites de courant dans un volume conducteur de forme arbitraire inhomogene, quand le courant est injecte par des electrodes placees sur sa surface. La determination des lignes de courant electrique a l'interieur d'un volume conducteur inhomogene spherique, soumis a des injections de courant au moyen d'electrodes constitue le probleme direct. En utilisant la methode des elements frontiere, les distributions de potentiel sur la surface et a l'interieur du volume sont calculees, ce qui permet de determiner les lignes de courant dans le domaine etudie. Un logiciel a ete developpe pour cette determination. L'imagerie d'impedance est une nouvelle technique d'imagerie medicale, qui a pour but de reconstruire une image de la distribution de conductivite electrique au sein d'un milieu physiologique, a partir d'informations recueillies a la peripherie de ce meme milieu. Elle apparait comme potentiellement complementaire aux autres techniques d'imagerie medicale et constitue le probleme inverse. Un algorithme de reconstruction en 2d et en 3d, utilisant la methode de la matrice directe de sensibilite, a ete realise. Cette methode est basee sur la relation existant entre la variation de conductivite d'un pixel donne c a l'interieur du domaine et la variation des perturbations de difference de potentiel de la frontiere du domaine. L'application en 3d de cette methode, qui s'affranchit de l'utilisation d'images de sections planes, a ete demontree a l'issue de cette etude. Enfin, une etude approfondie de la methode de retroprojection filtree a permis de developper un filtrage specifique ameliorant la qualite des images reconstruites
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Buš, Ondřej. "Přímý frekvenční číslicový syntezátor s externí synchronizací." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219881.
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This thesis deals with problematics of direct frequency digital synthesis. Principle and basic characteristics of this method of signal generating are explained in the introduction. It considers impact on purity of spectrum of output signal. Next chapter considers conception of the generator, namely choice of DDFS circuit and other basic blocks. Design of frequency multiplier, reconstruction filter and power amplifier are included. It also deals with choice of control circuit. The device is controlled by computer through USB. There was created user programme for this purpose. Measured characteristics are stated at the end of the work. This work includes schemes of connetions of designed parts including simulations and measured parameters.
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Ben, Bouallegue Fayçal. "Contributions en reconstruction TEP 3D par inversion directe." Montpellier 2, 2009. http://www.theses.fr/2009MON20078.
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Nous présentons deux contributions innovantes dans le domaine de la reconstruction par inversion directe en tomographie par émission de positons (TEP) 3D. D'abord, à partir d'une formulation étendue du rebinning analytique dans l'espace de Fourier 3D, nous développons un algorithme itératif de reprojection (FOREPROJ itératif) qui permet l'estimation des projections obliques manquantes sur la base de l'ensemble des projections mesurées. Il en découle, au premier ordre, une formulation étendue du Fourier rebinning (FORE étendu) et un algorithme de reprojection approximatif associé. Ces deux algorithmes sont évalués sur des simulations numériques de données TEP 3D pour résoudre le problème de la troncature axiale. Prenant avantage de l'ensemble de la statistique disponible, FOREPROJ itératif s'avère une alternative rapide et fiable aux méthodes classiques que sont FOREPROJ et la reprojection géométrique. Il améliore significativement la qualité des coupes reconstruites sans perte de résolution spatiale. Nous évaluons ensuite dans quelle mesure le choix de plan fixes pour paramétrer les projections permet de simplifier l'étape d'interpolation en fréquence requise par l'application du théorème de la projection de Fourier en 3D (3D-FST). Nous comparons l'implémentation directe de ce dernier avec un nouvel algorithme de gridding basé sur une géométrie à 2 plans fixes et ne nécessitant qu'une interpolation 1D dans l'espace de Fourier. Il apparaît que l'utilisation de deux plans orthogonaux conduit à un rapport signal à bruit dans les coupes reconstruites similaire à celui obtenu par le 3D-FST avec une statistique double, cela sans perte de résolutionWe present two innovative contributions in 3D positron emission tomography (PET) direct reconstruction. First, we develop an extended three-dimensional exact rebinning formula in the Fourier space that leads to an iterative reprojection algorithm (iterative FOREPROJ), which enables the estimation of unmeasured oblique projection data on the basis of the whole set of measured data. In first approximation, this analytical formula also leads to an extended Fourier rebinning equation that is the basis for an approximate reprojection algorithm (extended FORE). These algorithms are evaluated on numerically simulated 3D PET data for the solution of the truncation problem. By taking advantage of all the 3D data statistics, the iterative FOREPROJ reprojection provides a quick and reliable alternative to the classical FOREPROJ and geometric re-projection methods. It significantly improves the quality of the external reconstructed slices without loss of spatial resolution. Then we investigate how the choice of fixed planes for the representation of the projection data of a cylindrical PET scanner simplifies the frequency interpolation required by the 3D Fourier slice theorem (3D-FST). A new gridding algorithm based on a two-plane geometry and requiring only 1D interpolations in the Fourier domain is compared with the direct implementation of the 3D-FST. We show that the use of two orthogonal planes leads to signal to noise ratios similar to those achieved with the 3D-FST algorithm from projection data acquired with up to two times more count rates, while the resolution remains similar
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White, Timothy Andrew. "SPECT reconstruction directly from photomultiplier tube signals." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186926.
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Compton scatter in the object is an unsolved problem in single-photon emission computed tomography (SPECT). Current correction schemes in SPECT can be divided into three categories: those correction schemes that examine the spatial contribution of scattered photons, those schemes that examine the energy signature of scattered photons, and those techniques that examine both the spatial and energy aspects of detected photons. Our approach to scatter correction most closely resembles those in the third category. The SPECT systems that have been developed at the University of Arizona (UA) are stationary systems which consist of modular gamma cameras that view the object through a multiple-pinhole coded aperture. Characteristic of the UA SPECT systems is that the system response function (position-sensitive point-spread function) is measured; measuring the response function allows us some flexibility in our choice of the detector space in which we work. In a typical scintillation-camera system, the photomultiplier-tube (PMT) response to a gamma-ray interaction is used to estimate the interaction position and energy of the absorbed gamma ray. We call this estimate the pixel-space data. We could also use the digitized PMT signals directly as our data. Using PMT signals directly we avoid the possibility of misestimating the spatial and energy coordinates of scintillation events. We have proved that reconstructions from PMT-space data are of at least comparable quality to reconstructions from data in pixel space. In order to quantitate the difference between PMT and pixel spaces, we performed simulation studies and used the signal-to-noise ratio (SNR) of the ideal observer as our image quality metric. We simulated the projection of photons scattered zero to four times, and detected the simulated flux with cameras of different energy resolution and with the modular camera. We found that for the detection of a small cold tumor in a uniform background, the energy resolution of the simulated camera changed the SNR very little and there was little difference between the SNR from data in PMT and pixel spaces.
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Wyatt, Adam Stacey. "Spectral interferometry for the complete characterisation of near infrared femtosecond and extreme ultraviolet attosecond pulses." Thesis, University of Oxford, 2007. http://ora.ox.ac.uk/objects/uuid:22b7750a-6328-42c1-a7f6-965523858c05.
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This thesis describes methods for using spectral interferometry for the complete space-time characterisation of few-cycle near-infrared femtosecond pulses and extreme ultraviolet (XUV) attosecond pulses produced via high harmonic generation (HHG). Few-cycle pulses tend to exhibit one or more of the following: (1) an octave-spanning bandwidth, (2) a highly modulated spectrum and (3) space-time coupling. These characteristics, coupled with the desire to measure them in a single-shot (to characterise shot-to-shot fluctuations) and in real-time (for online optimisation and control) causes problems for conventional characterisation techniques. The first half of this thesis describes a method, based on a spatially encoded arrangement for spectral phase interferometry for direct electric-field reconstruction (SEA-SPIDER). SEA-SPIDER is demonstrated for sub-10fs pulses with a central wavelength near 800nm, a bandwidth over 350nm, and a pulse energy of several nano-Joules. In addition, the pulses exhibit a modulated spectrum and space-time coupling. The spatially-dependent temporal intensity of the pulse is reconstructed and compared to other techniques: interferometric frequency-resolved optical gating (IFROG) and spectral phase interferometry for direct electric field reconstruction (SPIDER). SEA-SPIDER will prove useful in both femtoscience, which requires accurate knowledge of the space-time character of few-cycle pulses, and in HHG, which requires the precise knowledge of the driving pulse for seeding into simulations and controlling the generation process itself. Pulses arising from HHG are known to exhibit significant space-time coupling. The second half of this thesis describes how spectral interferometry may be performed to obtain the complete space-time nature of these fields via the use of lateral shearing interferometry. Finally, it is shown, via numerical simulations, how to extend the SPIDER technique for temporal characterisation of XUV pulses from HHG by driving the process with two spectrally-sheared driving pulses. Different experimental configurations and their applicability to different laser systems are discussed. This method recovers the space-time nature of the harmonics in a single shot, thus reducing the stability constraint currently required for photoelectron based techniques and may serve as a complimentary method for studying interactions of XUV attosecond pulses with matter.
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Lee, Chang. "MITIGATION of BACKGROUNDS for the LARGE UNDERGROUND XENON DARK MATTER EXPERIMENT." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1427482791.
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Yang, Xiaojuan. "Microscopie super-résolutive aux synapses inhibitrices mixtes : régulation différentielle des GlyRs et des GABAARs par l’activité excitatrice." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEE012/document.
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La microscopie optique stochastique de reconstruction (STORM) contourne la limite de diffraction en enregistrant des signaux monomoléculaires spatialement et temporellement séparés, atteignant une résolution de ~10-40 nm. Dans mon étude, j'ai développé une stratégie d'imagerie et d'analyse de données dSTORM bicolore afin d'étudier l'ultrastructure des synapses inhibitrices mixtes. Mes résultats ont montré que les GlyRs, les GABAARs, la géphyrine et RIM1/2 présentent une organisation intra-synaptique hétérogène et forment des domaines sous-synaptiques (SSDs). Les GlyR et les GABAAR ne sont pas complètement mélangés, mais peuvent occuper des espaces différents à la densité post-synaptique (PSD). De plus, les SSD de géphyrine postsynaptique sont alignées avec les SSD de RIM1/2 pré-synaptiques, formant des nanocolonnes trans-synaptiques. Au cours d'une activité neuronale élevée par traitement 4-AP, la corrélation spatiale entre les GlyRs, les GABAARs et la géphyrine a augmentée au PSD. De plus, la corrélation spatiale des GlyRs et RIM1/2 a également augmenté, tandis que celle des GABAARs et RIM1/2 n'a pas changé. Le nombre de SSD par synapse pour ces protéines synaptiques n'est pas modifié par 4-AP. Cette étude fourni un nouvel angle de compréhension des mécanismes sous-jacents à la co-transmission GABAergique/glycinergiqueStochastic optical reconstruction microscopy (STORM) bypasses the diffraction limit by recording spatially and temporally separated single molecule signals, achieving a resolution of ~10-40 nm. In my study, I have developed a two-color dSTORM imaging and data analysis strategy, in order to investigate the ultrastructure of mixed inhibitory synapses. My results show that GlyRs, GABAARs, gephyrin and RIM1/2 exhibit a heterogeneous intra-synaptic organization and form sub-synaptic domains (SSDs). GlyRs and GABAARs were not fully intermingled, but sometimes occupied different spaces at the post-synaptic density (PSD). In addition, post-synaptic gephyrin SSDs were aligned with pre-synaptic RIM1/2 SSDs, forming trans-synaptic nanocolumns. During elevated neuronal activity by 4-AP treatment, the spatial correlation between GlyRs, GABAARs and gephyrin was increased at the PSD. Moreover, the spatial correlation of GlyRs and RIM1/2 was also increased, while that of GABAARs and RIM1/2 did not change. The number of SSDs per synapse for these synaptic proteins was not changed by 4-AP. My study thus provides a new angle for understanding the mechanisms underlying GABAergic/glycinergic co-transmission
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Yildiz, Mursel. "User Directed View Synthesis On Omap Processors." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610682/index.pdf.
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In this thesis, real time image rendering for hand held devices is studied according to user&rsquos view point choice and using image frames with corresponding depth maps obtained from 2 different cameras, of which positions on coordinate system is known. User&rsquo
s view point choice is restricted to the area between right, and left cameras. Occlusion handling methods for image rendering systems is explored and discussed together with frame enhancement techniques. Median filtering is studied for multicolor image frames and post processing methods are discussed for image enhancement at the end of rendering algorithm. In this thesis, OMAP3530 microprocessor is used as the main processor which processes suggested rendering algorithm with occlusion handling and frame enhancement. proposed algorithms are implemented on DSP core and ARM cores of OMAP3530 separately and their performances are evaluated through experiments. Embedded Linux (Kernel-2.6.22) is run as the operating system for applications. Driver usage together with devices for Linux embedded operating system is explored and studied. 3 boards are used for the realization of proposed system. OMAP35x EVM board from Mistral Solutions Company is used for processor utilization, high resolution LCD utilization, system monitoring, user interface and communication purposes. Two daughter cards are designed for user view point determination. First daughter card handles communication process with EVM board and calculates view point according to input from second daughter card with single axis response GYRO sensor (ADIS16060). Spartan®
-3A DSP FPGA family is utilized in this system for view point determination. DSP slices that are hardly present inside gate arrays of this FPGA family are utilized and their performance is studied. Asynchronous memory interface, i2c bus interface, SPI interface are studied and implemented on FPGA.
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Bergman, Fanny. "Goal-directed fluid therapy in major head andneck surgery with free flap reconstruction." Thesis, Örebro universitet, Institutionen för medicinska vetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-61581.
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BALL, JACQUES. "Transmission, diffusion elastique et reconstruction directe des amplitudes n-p entre 0. 8 et 1. 1 gev." Paris 11, 1992. http://www.theses.fr/1992PA112187.
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Le but du programme nucleon-nucleon a saturne ii etait de determiner des ensembles complets d'observables dans la diffusion np elastique et quasi elastique, pour acceder a la reconstruction directe des amplitudes. Les ensembles complets d'observables ont ete mesures dans un grand domaine angulaire pour des energies de 0. 84, 0. 88, 0. 940, 1. 00, et 1. 10 gev. En plus des parametres de diffusion elastique, la these contient des mesures de transmission qui determinent les differences de sections efficaces totales. Ces donnees determinent les parties imaginaires pour les amplitudes de diffusion vers l'avant et permettent de deduire les amplitudes de diffusion pour l'isospin zero. Le formalisme de la diffusion elastique du systeme nn est decrit. Le faisceau, la cible et la mesure de leur polarisation sont discutes. L'appareillage pour les differentes mesures est presente. Les resultats obtenus sont traites en detail et compares avec les donnees d'autres laboratoires. Les donnees des correlations des polarisations, des observables avec trois indices du spin, et des differences de sections efficaces polarisees avec des neutrons libres ont ete mesurees, pour la premiere fois, a saturne ii lors de cette experience
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Kouřilová, Vendula. "Analýza vlivu rekonstrukce na obvyklou cenu rodinného domu v Kyjově." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241186.
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The subject of this master thesis is detection how the redevelopment and refurbishment affect regular price of family house. For valuation I chose the building in which I grew up so I know it very good. The family house is located in small south-moravian town Kyjov, in district Nětčice. The family house has a basement and two upper floors. Constructions were completed in 1962. Since 1976 many quite expensive redevelopment and refurbishment have been done. For property valuation is used method of direct comparison with the use of database of similar family houses in Kyjov and also cost method according to law number 441/2013 Sb. Valuation is done in two versions – for building in original condition (in 1985) and in current condition. All at once a couple of variants of redevelopment, which are common nowadays, and for one variant is made the itemized budget. Result of this master thesis should be detection if it is better to buy house after redevelopment and refurbishment or house in original condition and make these structural modifications until then.
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Machefert, Frederic. "Mesure de la masse du boson W par la méthode de reconstruction directe dans l'expérience aleph au LEP." Palaiseau, Ecole polytechnique, 1998. http://www.theses.fr/1998EPXX0022.
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La masse du boson W est un paramètre fondamental du modèle standard qui décrit la matière et ses interactions. Sa mesure précise permet de tester le modèle et d'imposer de nouvelles contraintes sur certains de ses paramètres comme la masse du boson de Higgs. Depuis 1996, l'énergie dans le centre de masse du collisionneur LEP au CERN a été progressivement augmentée pour permettre la production par interactions e#+e# de paires de bosons W et de mesurer sa masse, d'abord par la méthode de mesure au seuil puis par la méthode de reconstruction directe des produits de désintégration des paires w#+w#. Les données accumulées par le détecteur aleph durant les années 1996 et 1997, qui correspondent à des luminosités intégrées de 10. 65 et 57. 01 pb##1 a des énergies moyennes dans le centre de masse de 172. 1 et 182. 7 gev respectivement, sont utilisées pour déterminer la masse par la méthode de reconstruction directe dans les deux canaux de désintégration des bosons w : les canaux hadronique et semi-leptonique.
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Denneulin, Laurence. "Approche inverse pour la reconstruction des environnements circumstellaires en polarimétrie avec l'instrument d'imagerie directe ESO / VLT SPHERE IRDIS." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSE1183.
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L'étude des environnements circumstellaires permet d'en apprendre plus sur la formation des exoplanètes. Si les avancées instrumentales permettent la résolution de ces environnements, leur observation en imagerie directe est difficile du fait du grand contraste entre les environnements et leurs étoiles hôtes. En effet, celles-ci sont 1000 à 10 000 fois plus brillantes, ou encore 10 000 000 fois dans le cas des exoplanètes. Lors de l'acquisition directe d'image de ces environnements, leur signal est mélangé au résidu de lumière stellaire. Or, la lumière de l'environnements circumstellaires est partiellement polarisée linéairement, tandis que le résidu de lumière stellaire ne l'est pas. Le sous-instrument Infrared Dual-band Imaging and Spectroscopy (IRDIS) de l'instrument de l'European Southern Observatory (ESO) appelé Spectro-Polarimeter High-contrast Expolanet REsearch (SPHERE), situé sur l'un des quatre Very Large Telescopes (VLT) dans le désert d'Atacama au Chili, acquiert des jeux de données où la polarisation linéaire est modulée en rotation, selon plusieurs cycles d'angles connus. Ainsi, par combinaison de ces données, il est possible de démélanger la lumière diffusée par l'environnement circumstellaire et la lumière de l'étoile. Les méthodes de l'état-de-l'art permettant ce démélange, ne prennent en compte ni le bruit de photon, qui domine le signal d'intérêt, ni le bruit de lecture du détecteur. De plus, si une image du cycle de rotation est manquante, les autres images du cycle sont supprimées. Par ailleurs, le traitement par interpolation des pixels morts, le recentrage des images et toutes éventuelles rotations et déconvolutions des données, sont fait indépendamment du démélange. De ce fait, la propagation des erreurs n'est pas contrôlée.Les méthodes de types « problèmes inverses » permettent, à partir d'un modèle direct des données, de procéder au démélange tout en ayant le contrôle sur la propagation des erreurs dans les reconstructions. Une telle approche n'a jamais été développée pour l'imagerie directe en polarimétrie. Le but de ma thèse, est de reconstruire de manière optimale, à partir des données polarimétriques de l’instrument ESO/VLT-SPHERE IRDIS, des cartes de la lumière polarisée des environnements circumstellaires, des angles de polarisation associés et des résidus lumineux de l'étoile et de la lumière non-polarisée de l'environnement. Je propose tout d’abord un modèle physique séparable des données, paramétré non-linéairement en ces quantité d’intérêt et linéairement en les paramètres de Stokes, à partir duquel ces quantités peuvent être estimées. Ensuite, je complexifie le modèle en y incluant recentrage, rotations et convolution, le rendant ainsi non-séparable. Les paramètres sont alors estimés par la minimisation de la co-log-vraissemblance des données, sous contraintes, de positivité dans le cas non-linéaire ou épigraphique dans le cas linéaire. Dans le cas non-séparable, un terme de régularisation est également ajouté, comme la variation totale et la norme de Shatten sur le Hessien. Selon les propriétés des fonctions considérées dans le critère, je procède à sa minimisation par différents algorithmes tels que l’algorithme Variable Metric Limited Memory and Bound, Forward-Backward avec backtracking et l’algorithme primal-dual préconditionné Condat-Vu avec backtracking. Je propose également une méthode de réglage automatique des poids des régularisations à partir de l’estimateur non-biaisé du risque de Stein (SURE). L’ensemble de ces méthodes d'estimation sont appliquées sur des données synthétiques et sur données astrophysiques. Je montre alors que l’utilisation d’un modèle directe complet des données, prenant en compte le recentrage, les rotations et la convolution, ainsi que l’estimation de ses paramètres à partir d’un critère régularisé sous contrainte, prenant en compte la précision des mesures et les données manquantes, permet de réduire l’erreur faite sur l’estimation des observablesCircumstellars environments observation is a key for the comprehension of planet formation. If the very large telescopes allow the resolution of these environments, their observation is difficult due to the high contrast between the environment and their host stars. In fact the host stars are 1000 to 10 000 times brighter than the environment, even 10 000 000 times brighter for exoplanets. When images of these circumstellar environnements are acquired in direct imaging, the signal of the environnements mixed to star light residuals. Yet, the light of the environment is partially linearly polarized while the light od the star is unpolarized. The instrument Infrared Dual-band Imaging and Spectroscopy (IRDIS) of the European Southern Observatory’s (ESO) Spectro-Polarimeter High-contrast Expolanet REsearch (SPHERE) instrument, installed at one of the four Very Large Telescopes (VLT) in Atacama in Chile, acquires datasets where the polarization is modulated according to a known angles cycle. It is then possible, by combinations of the data, to extract the polarized signal of the environment from the unpolarized residual light of the stars and unpolarized light of the disks. The stat-of-the-art methods to extract such signal do not take optimally into account the photon noise statistics of the data, which dominate the signal of interest, nor the read out noise of the detector. Moreover, if any image from a rotation cycle is missing, the rest of the cycle is not used. Finally, any centering and rotation of the data or deconvolution by the PSF is generally performed in separated steps from the data reduction. The bad pixels and dead pixels are interpolated before the processing. The consequence of such approach is that the propagation of the errors in the data is not controlled.The « inverse problem » methods allow such processing while controlling the error propagation in the reconstructions. These approaches have never been developed, so far, for high contrast direct imaging in polarimetry. My goal in this thesis is to optimally reconstruct, from the polarimetric data of the instrument ESO/VLT-SPHERE IRDIS, maps of the circumstellar environments polarized light, the ascociated polarization angles and the unpolarized star light residuals and circumstellar environments light. First, I develop a nonlinear physical model of the data, pixelwise independent, parametric in these quantities of interest, or linear with respect to the Stokes parameters, from which they can be estimated. Throughout this thesis, I complete the model by adding centering, rotations and convolutions, making it pixelwise dependent. The parameters are then estimated by the minimization of an objective function, derived from the co-log-likelyhood of the data, under some constraint, such as positivity constraint or epigraphical constraint, and regularizations as smooth and non-smooth Total Variation and the Shatten norm on the Hessian. This methods are all applied on simulated datasets, created to reproduce typical astrophysical datasets obtained in circumstellar environment polarimetrical direct imaging. Depending of the properties of the functions considered in the objective function, the research of its minimum is done with different algorithms as the Variable Metric Limited Memory and Bound algorithm, Forward-Backward with backtracking and the preconditioned primal-dual Condat-Vu algorithm with backtracking. I also use the Stein Unbiased Risk Estimator to auto-tune the weights of the regularization. In the results, I show that the use of a complete direct model of the data, taking in account the recentering, the rotations and the convolution and the estimation of its parameters from a constraint problem, taking in account the measure precision and the missing data reduces the error on the estimation maps in such astrophysics context
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Lauzon, Michael. "Reconstruction of Convex Bodies in the Plane from Three Non-Collinear Point Source Directed X-Rays." Scholarship @ Claremont, 2000. https://scholarship.claremont.edu/hmc_theses/121.
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When one takes an x-ray, one learns how much material is along the line between the x-ray source and the x-ray sensor. The goal of tomography is to learn what one can about an object, by knowing how much material is on a collection of lines or rays passing through that object. Mathematically, this is a collection of line integrals of density function of the object. In this paper, we provide and prove reconstructions for a class of convex objects of uniform density using x-rays from three point sources.
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Braeunig, Jean-Philippe. "Sur la simulation d'écoulements multi-matériaux par une méthode eulérienne directe avec capture d'interfaces en dimensions 1, 2 et 3." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2007. http://tel.archives-ouvertes.fr/tel-00262277.
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La méthode présentée dans ce mémoire vise à résoudre numériquement les équations d'Euler en 2D/3D modélisant l'écoulement de plusieurs matériaux compressibles, non-miscibles et de nature différentes. Il s'agit en particulier de reconstruire une interface d'épaisseur nulle entre ces matériaux, sans introduire de mélange entre eux. L'originalité de cette méthode purement eulérienne réside dans l'utilisation d'un schéma volumes finis direct. Le concept de ”condensat” est introduit et étudié dans ce mémoire, qui permet de calculer l'évolution de l'interface dans la grille eulérienne fixe. De plus, cette méthode permet un glissement parfait des matériaux les uns par rapport aux autres et une conservation locale des grandeurs eulériennes. La qualité de la méthode est évaluée par des cas-tests académiques ainsi que par des cas-tests éprouvant la robustesse de la méthode
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Rolnik, Vanessa Portioli. "Contribuição ao desenvolvimento de uma nova técnica de reconstrução tomográfica para sondas de visualização direta." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-20032017-112619/.
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O principal objetivo deste trabalho é contribuir para o desenvolvimento de uma nova técnica de reconstrução numérica do problema de tomografia por impedância elétrica. A abordagem adotada baseia-se na minimização de um funcional de erro convenientemente definido, cujo ponto de mínimo global está relacionado com a imagem do escoamento sensoriado. Nesta formulação, o mau condicionamento se manifesta através de características topológicas dos funcionais de erro (patologia) que prejudicam o desempenho dos métodos de otimização na obtenção do mínimo. Esta abordagem tem vantagens significativas em relação às abordagens tradicionais, normalmente baseadas em hipóteses restritivas e pouco realistas como, por exemplo, considerar o campo de sensoriamento bidimensional e paralelo, além de independente do escoamento. Testes numéricos permitiram realizar estudos preliminares sobre as características topológicas do funcional de erro, necessários para a seleção de métodos de otimização passíveis de serem especializados para a solução do problema tratado neste trabalho. Nestes testes identificou-se a patologia característica do problema tratado: presença de uma região plana (inclinação virtualmente nula) circundando o mínimo global procurado. Dentre os diferentes métodos de otimização considerados, optou-se pelo desenvolvimento de uma estratégia baseada em algoritmos genéticos, devido às suas características serem melhor adaptáveis à patologia do problema em questão. O desempenho do método de otimização desenvolvido foi testado extensivamente em dois problemas básicos: a) posicionar corretamente uma inclusão de forma e contraste conhecidos e b) determinar os valores do contraste em uma sub-região do domínio de sensoriamento, no interior do qual sabe-se que existe uma inclusão. No primeiro caso, os resultados mostraram que, de fato, o algoritmo genético superou a patologia do problema e convergiu para a solução correta. No segundo caso, de dimensionalidade maior, a convergência em um tempo aceitável só pode ser alcançada com a introdução de informações à priori, seja na forma de restrições sobre o espaço de busca, seja na forma de penalidades aplicadas ao funcional de erro.The main objective of this work is to contribute to the development of a new two-phase flow tomographic reconstruction method suited for electrical impedance tomography. The adopted approach consists in minimizing an error functional, defined so that is global minimum is related with the sensed flow image. In this formulation, the ill conditioning appears through topological features of the error functionals (pathologies) which compromises the performance of the optimization algorithms employed to determine the minimum. This approach has several important advantages over the classical ones, generally based on restrictive and unrealistic hypothesis such as the sensing field being two-dimensional, parallel and independent of the flow. Numerical simulations permitted to conduct preliminary studies about the topological features of the error functional, necessary to select possible optimization methods to be specialized to reach the solution of the problem treated in this work. The characteristic pathology of the problem was identified in these tests: the presence of a flat region (virtually null inclination) around the sought global minimum. Among the different considered methods, genetic algorithms were adopted because of their characteristics of being best adaptive to the pathologies of the current problem. The performance of the developed optimization method was tested through extensive numerical tests in two basic problems: a) to correctly place aninclusion with known shape and contrast and b) to determine the values of the contrast inside a sub-region of the sensed domain, which is known that contains the inclusion. In the first case, results show that the genetic algorithm overcame the pathologies of the problem and converged to the correct solution. In the second case, with higher dimensionality, convergence was achieved in an acceptable time only after the introduction of a priori information, either in the form of restrictions on the search space or in the form of penalties applied to the error functional.
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Lakhal, Mohamed. "Méthodes d'inversion pour la reconstruction de mines enfouies à partir de mesures d'antennes radar." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX034/document.
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Ce travail thèse s’inscrit dans le cadre du projet FUI Tandem portant sur l’imagerie radar de mines enfouies dans un sol sec par des antennes héliportées. Les données d’antennes correspondent à des mesures de champ électromagnétique (composante tangentielle à l’antenne) en configuration « back-scattering » : une seule antenne émettrice-réceptrice. L’objectif premier de la thèse est de valider/modifier la méthodologie SAR (Synthetic Aperture Radar) proposée par les ingénieurs pour traiter les données d’antenne et imager les mines. La difficulté essentielle réside dans le fait que la méthode SAR repose sur le principe d’un milieu de référence homogène alors que le cas d’étude ne l’est pas. Nous avons étudié l’incorporation d’une approximation bicouche du milieu de référence pour corriger l’effet du sol et obtenir des images moins sensibles à l’effet de celui-ci. La première solution consiste à mimer la technique SAR pour construire une indicatrice de la géométrie via la rétro-propagation de la donnée dans le milieu bi-couche en utilisant la formule donnée par l’approximation de Born. La deuxième option, beaucoup plus coûteuse numériquement consiste à inverser le modèle de Born avec une technique de régularisation de type variation totale. Nous nous intéressons dans une deuxième partie à l’adaptation de méthodes d’inversion de type MUSIC (MUltiple SIgnal Classification) pour retrouver l’information « profondeur » non fournie par les méthodes SAR. S’inspirant de la problématique Tandem, nous avons proposé l’extension de ces méthodes au cas de données en configuration quasi-back-scattering : une antenne émettrice couplée à un réseau 1D d’antennes réceptrices. La méthodologie est complètement nouvelle et la justification de la méthode repose sur l’analyse asymptotique du problème de diffraction dans le régime petit obstacle et champ lointain. L’étude a également été étendue à des configurations cylindriques qui pourraient être adaptées à l’imagerie bio-médicaleThis work is part of the FUI Tandem project on radar imaging of mines buried in dry ground by heliborne antennas. The antenna data correspond to measurements of the electromagnetic field (component tangential to the antenna) in the back-scattering configuration: a single transmitter/transceiver antenna. The primary objective of the thesis is to validate / modify the SAR (Synthetic Aperture Radar) methodology proposed by engineers to process the antenna data and to image the mines. The main difficulty lies in the fact that the SAR method is based on the principle of a homogeneous background whereas the study case is not. We have studied the incorporation of a two-layer approximation of the reference medium to correct the effect of the soil and to obtain images that are less sensitive to the effect of the latter. The first solution consists in mimicking the SAR technique to construct an indicator of the geometry via the back propagation of the data in the bi-layer medium using the formula given by the Born approximation. The second option, much more costly numerically consists in inverting the Born model with a regularization technique of the total variation type. In a second part, we are interested in adapting MUSIC (MUltiple SIgnal Classification) methods to retrieve the "depth" information not provided by SAR methods. Based on the Tandem experiement, we proposed the extension of these methods to the case of data in quasi-back-scattering configuration: a transmitting antenna coupled to a 1D array of receiving antennas. The methodology is completely new and the justification of the method is based on the asymptotic analysis of the scattering problem in the small obstacle and far field regime. The study was also extended to cylindrical configurations that could be adapted to biomedical imaging
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Scherer, Kátia Ragnini. "A função do direito na fase da reconstrução identificada pela gestão circular dos desastres climáticos." Universidade do Vale do Rio dos Sinos, 2017. http://www.repositorio.jesuita.org.br/handle/UNISINOS/6468.
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A tese tem como tema a função do Direito na reconstrução identificada pela gestão circular dos desastres climáticos. A delimitação centra-se na função do Direito no estágio da reconstrução pós-desastre. O problema proposto consiste em saber: sob quais condições a policontexturalidade dos SE instrumentaliza a função do Direito na reconstrução identificada pela gestão circular dos desastres climáticos? O objetivo geral é analisar reflexivamente as possibilidades de observação do Direito em relação à policontexturalidade dos SE e a gestão circular do Direito para a reconstrução resiliente no pós-desastre. A estrutura do trabalho está construída de modo que cada capítulo acompanhe cada objetivo específico, sendo estes: a) examinar como o Direito observa os riscos climáticos para estabelecer os fundamentos da gestão pelo Direito; b) abordar a gestão cíclica dos desastres climáticos e sua assimilação pelo contexto jurídico nacional e; c) analisar reflexivamente a instrumentalidade policontextural dos SE e sua aderência ao estágio da reconstrução, por meio da diferenciação funcional para prevenção das catástrofes climáticas. O método de abordagem é o sistêmico funcional, o de procedimento é o monográfico e a técnica de pesquisa é a bibliográfica. A pesquisa confirma a hipótese no sentido de que na reconstrução resiliente os serviços ecossistêmicos devem ser assimilados pelo Direito a partir de elementos oriundos de múltiplos contextos com o da Ciência, da Política e da Economia. Tal assimilação, por sua vez, deve operar de forma recíproca pelas organizações nos processos de avaliação, monitoramento e estruturação das decisões jurídicas de curto e de longo prazos, considerando que o contexto jurídico nacional inclui a prevenção como força motriz no tratamento dos desastres pela abordagem sistêmica de ações (prevenção, mitigação, preparação, resposta e recuperação) e pela integratividade de políticas públicas. Assim é possível uma evolução para assimilação da infraestrutura natural oferecida pelos serviços ecossistêmicos com a diferenciação funcional para a prevenção e a precaução no enfrentamento aos desastres climáticos.
The thesis takes the theme of the function of Right in the reconstruction identified by the circular gestion of climatic disasters. Its limits center on the function of Law at the time of reconstruction post-disaster. The proposed problem consists in knowing: under what conditions are Ecosystem Services polycontexturality instrument for circular management of climatic disasters through Right, separated from the reconstruction stage? The general goal is to analyze reflexively the observation possibilities of Law in relation of the polycontexturality of ecosystem services and the circular management of Law for resilient reconstruction after the disaster. The structure of work is built so that every chapter follows his specific goals, which are: a) to examine how Law studies climatic risks to establish the fundamentals of Law management; b) approach the cyclic management of climatic disasters and their assimilation by the national legal context and; c) analyze reflexively the polycontexturality instrumentality of the ES and its adherence to the stage of reconstruction through the functional changes to prevent climatic disasters. The approach method is the systemic functional one, the proceeding is the monographic one and the research is bibliographic. The research confirms the hypothesis in the sense that in a resilient reconstitution, ecosystem services must be assimilated by Law, starting from elements coming from multiple contexts with Science of Politics and Economy. Such assimilation must operate reciprocally by the organizations through processes of evaluation, monitoring and structuring of legal decisions in the long and short terms, considering the national legal context and including prevention as the driving force in the treatment of disasters through systemic actions of approach (prevention, mitigation, preparation, response and recovery) and through the integration of public policies. This way, an evolution is possible to assimilate the natural infraestracture offered by ecossistemic services with function diferences for prevention and the precaution in face of climatic disasters.
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Moreau, Cédric. "Stratégies de reconstruction du sens en langue des signes française à partir de données incomplètes en et hors contexte : perspectives pour la constitution d’un lexique-dictionnaire à entrée directe en langue des signes." Paris 8, 2012. http://www.theses.fr/2012PA083515.
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Si l’esprit peut isoler de manière pertinente les structures minimales de réalisation en langue des signes, comme étant des éléments porteurs de sens, il faut obligatoirement, pour les mettre en activité dans une communication, les effectuer simultanément. Ce constat nous conduit à définir un nouveau paradigme qui se revendique des théories de l’iconicité, de la Gestalt et des catastrophes. Fort de ce cadre théorique, nous mettons en évidence et décrivons les stratégies déployées par les locuteurs lors de leurs tentatives de reconstruction du sens, à partir de données tronquées hors et en contexte. Notre travail permet également d’envisager des pistes de réflexion pour la mise en œuvre de dictionnaires / de lexiques en langue des signes. Ces outils seraient construits à partir notamment de la prégnance de sous-espaces morphémiques primaires et secondaires mais aussi de la pondération dynamique des unités morphémiques les constituant. Nous soulignons également la nécessité évidente de ne pas limiter les éléments figurants dans les dictionnaires actuels aux simples signes lexicalisés mais de les élargir aux structures de transfertsWhile the mind can isolate, in a relevant way, minimum production structures in sign language as meaningful elements, they must be performed simultaneously, to be activated in real life communication. Therefore a new paradigm can be defined claiming from iconicity, Gestalt and catastrophe theories. This theoretical framework leads us to identify and describe the strategies used by signers in their attempts to reconstruct meaning from truncated input data in and out of context. This work provides for new issues for reflection in the making of sign language dictionaries / lexicons. These tools should be built from the prägnanz of such primary and secondary morphemic subspaces but also from the dynamic weighting of constituting morphemic units. We should also underline the need for not limiting the elements in current dictionaries to single lexicalized signs but extending them to transfer structures
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Franková, Markéta. "Návrh na rozšíření mateřské školy." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2013. http://www.nusl.cz/ntk/nusl-223756.
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This thesis analyzes the current state of the selected Kindergarten. Based on the analysis made a proposal to extend kindergarten, due to lack of capacity building. The thesis is designed to address deficiencies occurring in kindergarten. It created a proposal to extend the new kindergarten class together with the calculation of the costs incurred and revenues.
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Li, Jian-Jin. "Algorithmes parallèles pour la synthèse d'image sur machines à mémoire distribuée." Lyon 1, 1992. http://www.theses.fr/1992LYO10080.
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Cette thèse est consacrée à l'étude et à la conception d'algorithmes graphiques parallèles sur les machines MIMD à mémoire distribuée. Après une étude générale sur les architectures parallèles et la parallélisation des algorithmes graphiques, nous détaillons nos travaux qui ont porté sur plusieurs thèmes différents : l'implémentation d'un algorithme de reconstruction tridimensionnelle sur divers machines, à l'aide d'un module de communication PPCM que nous avons développé pour pallier à l'absence de tout langage et environnement standard sur les machines parallèles. Ensuite, deux algorithmes de visualisation des données volumiques ont été parallélisés. Le z-buffer est parallélisé de deux façons complémentaires sur un supernode. Dans la première approche, la scène est distribuée aux processeurs configurés en arbre. L'image est produite de manière pipelinée. Dans la deuxième approche, l'image aussi bien que la scène sont distribuées aux processeurs connectés en anneau. Une redistribution dynamique des objets est accomplie avant la projection des objets. L'implémentation parallèle d'un algorithme de visualisation directe est effectuée sur un hypercube IPSC860 avec un algorithme d'équilibrage dynamique de taches. Un nouveau modèle d'éclairage pour les données volumiques est également développé. Une discussion sur l'équilibrage des taches, la diminution du temps de communication est menée à la fin de cette thèse. Deux algorithmes de multi-distribution sur le réseau cycles connectés en cube sont développés au cours de cette étude. Les formules du temps d'exécution de ces deux algorithmes sont aussi fournies
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Courte, Josquin. "Étude de la propagation prion-like de l'alpha-synucléine dans des réseaux de neurones reconstruits Reconstruction of directed neuronal networks in a microfluidic device with asymmetric microchannels Neurotoxicity of the Cyanotoxin BMAA Through Axonal Degeneration and Intercellular Spreading." Thesis, Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2019SORUS053.pdf.
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Les maladies neurodégénératives (telles que les maladies de Parkinson et d’Alzheimer) sont caractérisées par l’agrégation de protéines mal repliées en dépôts insolubles. Ces dépôts engendrent des dysfonctions cellulaires, et semblent donc avoir un rôle fondamental dans le développement de ces pathologies. L’apparition de ces dépôts se fait de façon stéréotypée dans des sous-groupes de patients. Notamment, dans la maladie de Parkinson, la petite protéine présynaptique alpha-synucléine (aSyn) est le composant principal d’agrégats dénommés corps de Lewy et neurites de Lewy. Les corps et neurites de Lewy apparaissent suivant un patron dénommé « staging de Braak » dans une sous-partie conséquente des patients. Dans une certaine mesure, le patron d’apparition des agrégats semblent suivre la connectivité neuro-anatomique entre les régions cérébrales, ce qui suggère que l’agrégation puisse se propager dans les réseaux neuronaux.L’étude des maladies prions telles que le kuru ou la maladie de Creutzfeldt-Jakob a mis en évidence un mécanisme original de propagation du mérepliement des protéines. La protéine PrP s’agrégeant dans ces pathologies est en effet capable d’adopter au moins deux conformations radicalement distinctes. L’une, pathologique, forme des agrégats, tandis que la forme fonctionnelle ne s’agrège pas. Par des mécanismes encore mal compris, mais qui potentiellement similaires à la formation de fibres amyloïdes, la protéine pathologique est en mesure de convertir la protéine fonctionnelle en sa forme anormale, et à l’inclure dans des agrégats. La forme anormale de la protéine est donc capable de s’auto-propager, et cela de cellule à cellule et d’organisme à organisme. De nombreuses similitudes dans les caractéristiques biochimiques et moléculaires des agrégats présents dans les maladies neurodégénératives non prions ont mené à l’hypothèse que l’agrégation protéique se fait suivant des modalités similaires aux maladies à prions. Suivant ce scénario, l’agrégation protéique est en mesure de se propager de neurone à neurone dans le cerveau via les connexions neuronales, et ainsi suivre un patron stéréotypé dépendant de l’interconnexion des régions successivement touchées. Cette hypothèse est dénommée « prion-like ».Cependant, les mécanismes expliquant la génération d’un patron stéréotypé de développement prion-like des agrégats d’aSyn restent obscurs. Le but de ma thèse a été d’aborder les déterminants de la propagation de l’agrégation de l’aSyn dans des réseaux de neurones hétérogènes grâce à des modèles in vitro. J’ai tout d’abord évalué si différentes régions du cerveau de souris mises en culture primaire présentaient la même vulnérabilité au recrutement de l’aSyn soluble dans des agrégats pathologiques introduits dans le milieu extracellulaire. J’ai pu mettre en évidence que la vulnérabilité de neurones striataux, corticaux et hippocampaux était fortement différente, et que le facteur déterminant cette vulnérabilité était le niveau d’expression endogène de l’aSyn. J’ai ensuite développé un système de culture permettant la reconstruction contrôlée de réseaux de neurones binaires in vitro, composés de neurones primaires murins, dont les connexions sont parfaitement orientées d’un compartiment vers l’autre, un prérequis pour l’étude de la propagation d’un agent pathogène auto-propagatif. Un tel système est parfaitement original, et n’avait jamais été publié auparavant. J’ai finalement modélisé la propagation prion-like de l’aSyn dans de tels réseaux, en y introduisant des agrégats exogènes d’aSyn fluorescents dans le compartiment « présynaptique » et en évaluant la propagation de l’agrégation au compartiment « postsynaptique ». Ce transfert ne peut se faire que via les connexions neuronales poussant depuis le compartiment présynaptique, les deux compartiments étant fluidiquement isolés. [...]Neurodegenerative diseases such as Parkinsons’s or Alzheimer’s diseases are characterized by the aggregation of misfolded proteins in insoluble inclusions. These inclusions trigger cellular dysfnctions and are therefore thought to play an important role in the development of these pathologies. They appear following a conserved pattern in subgroups of patients. In Parkinson’s disease, the small presynaptic protein alpha-synuclein (aSyn) is the main component of protein deposits termed Lewy bodies and Lewy neurites. These appear following a stereotypical pattern known as “Braak staging” in a consequent subset of patients. The pattern of inclusion formation partly follows neuroanatomical connectivity, suggesting that protein aggregation propagates in neural networks. Prion diseases such as kuru or Creutzfeldt-Jakob’s disease have revealed an original mechanism for propagating protein misfolding. The PrP protein, aggregated in these diseases, is able to have two radically distinct conformations. The pathological one aggregates in supramolecular assemblies, while the functional one does not. Through an incompletely understood mechanism which might share similarities with the formation of amyloid fibrils, the pathological form of the protein is able to convert the functional form into the pathological one, recruiting it into aggregates. The abnormal form of the protein is thus able to self-propagate, from cell to cell and from organism to organism. Numerous biochemical and molecular characteristics of aggregates detected in neurodegenerative diseases are shared with the prion aggregates. It is thus hypothesized that protein aggregation in neurodegenerative diseases unfolds in a similar manner to prion aggregation. In this scenario, protein aggregation is able to be transmitted from neuron to neuron following neuroanatomical connectivity, and thus propagates in a stereotypical manner in neural networks following axonal tracts. This scenario is named “prion-like hypothesis”. However, how the prion-like propagation of aSyn generates the conserved pattern of aggregates in the brain of patients is still unknown. The aim of my PhD thesis has been to decipher parameters impacting the prion-like propagation of aSyn in heterogeneous neural networks with in vitro models. I first assessed if specific neuronal populations cultured from various regions of the mouse brain exhibited the same vulnerability to the prion-like recruitment of aSyn in pathological aggregates following their exposure to exogenous aSyn fibrils. I was able to demonstrate that cortical, striatal and hippocampal primary neuronal cultures had a significant difference in their vulnerability to prion-like seeding of aSyn aggregation. I also demonstrated that this vulnerability was due to the differential expression of aSyn in these populations. I then developed a culture system allowing for the controlled reconstruction of primary murine neurons networks. This system allows for the perfect filtration of axonal outgrowth in one direction, thus allowing the reconstruction of fully oriented binary networks. Axonal growth orientation is a prerequisite to the in vitro study of pathogens propagation in neural networks. This system is the first to achieve this level of axonal filtration while allowing synaptic connectivity between the two compartments. I finally modeled aSyn prion-like propagation in these reconstructed networks by selectively introducing exogenous fluorescent aSyn fibrils in the “presynaptic” compartment and following aggregation propagation to the “postsynaptic” compartment. This propagation can only occur through crossing axons, as the two compartments are fluidically isolated. I demonstrated that anterograde aSyn prion-like propagation was relatively inefficient in this experimental framework. Indeed, while a small quantity of exogenous fibrils are transferred to postsynaptic neurons, they are not able to seed endogenous aSyn aggregation in those. [...]
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Kolouchová, Hana. "Vliv stavebních úprav na cenu nemovitosti typu rodinný dům v lokalitě Hrotovice a okolí." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-232779.
Full textAbstract:
The topic of my diploma thesis is to compare the differences of real estate property prices before and after reconstruction with the real price of the conversion. It focuses on finding out whether the recontruction increases the value of the real estate property. The theoretical part describes the terminology being used in my diploma thesis. I also describe in more detailes price estimated family houses and their localities. The practical part contains price calculations of the family houses before and after reconstruction. As the valuation methods are used cost method in accordance with the applicable valuation regulations and method of direct comparison. In the conclusion there is a comparison between the prices before and after the reconstruction.
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Ivaldi, William. "Synthèse de vue frontale et modélisation 3D de visages par vision multi-caméras." Paris 6, 2007. http://www.theses.fr/2007PA066221.
Full textAbstract:
Cette thèse préparée avec SAGEM Sécurité, leader mondial en biométrie, a pour objectif d'étudier un système temps-réel de reconstruction faciale pour une application de reconnaissance de visages. L'algorithme doit générer une vue frontale d'un visage inconnu, sans contrainte de pose et sans arrêt devant les 4 caméras vidéo latérales. Après les méthodes classiques en double stéréovision, des modèles déformables de type AAM sont aussi évalués mais leur mode de déformation ne permet pas d'obtenir un ajustement acceptable sur des visages inconnus. Un Modèle 3D Radial est alors construit par projection hémisphérique d’exemples scans 3D afin d'obtenir des modes de représentation et d'instanciation satisfaisants. Après l'ajustement du modèle radial, l'image frontale est obtenue par fusion des 4 vues à l’aide d’un critère de visibilité calculé sur toute la surface du modèle. La vue virtuelle selon la normale visage du modèle est synthétisée en temps-réel par le GPU de la carte graphiqueThe purpose of this thesis prepared with SAGEM Sécurité, worldwide biometry leader, is to study a real-time system of facial reconstruction for a face recognition application. The algorithm must generate a frontal view of an unknown face, without constraint when walking behind the 4 video cameras. After testing a classic stereovision approach, we evaluate the well know AAM models but their deformation mode doesn't give any acceptable convergence on unknown faces. We then define an original 3D Radial Model by hemispheric projection of 3D face scans to get deformation modes adapted to the constraints. After the 3D radial model is ajusted, the frontal view is obtained by fusion of the 4 source images using a visibility rule applied at every position of the model surface. This virtual view is computed from a frontal point of view depending of the 'face' normal of the model. The virtual view synthesis is performed in real time using the graphic card GPU ressources
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Freijomil, Seoane Mariana. "Retorno(s) a Europa: genealogía de un modelo de reconstrucción histórica en el cine y la televisión contemporáneos." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/668722.
Full textAbstract:
Esta tesis se centra en las reconstrucciones históricas en el cine europeo y su principal objetivo es delimitar la genealogía de un modelo de figuración y transmisión de la historia, enraizado en la modernidad y que emerge tras la Segunda Guerra Mundial, persistiendo en el cine y televisión contemporáneos. Dicho modelo tiene por eje central imágenes cuya puesta en escena arrastra al espectador al tiempo representado, que se figura en la pantalla como una experiencia sensorial y dialéctica gracias a la cual la audiencia puede efectuar una relectura de la historia.
La aproximación háptica y dialéctica al pasado permite construir imágenes que operan como espacios de experiencia para el espectador, generándose una temporalidad que evoca la vivencia del tiempo histórico pero también genera una nueva visión del presente. A través de esta mirada a la historia y sus reconstrucciones cinematográficas exploramos las temporalidades que se generan tanto en la escritura histórica a través de la imagen como en su encuentro con la audiencia.This thesis focuses on historical reconstructions in European cinema and its main objective is to define the genealogy of a model of figuration and transmission of history, rooted in modernity and emerging after World War II, persisting in contemporary film and television. This model has main axis images whose mise-en-scene drags the viewer to the time represented, thanks to figuring it as a sensory and dialectical experience that allows the audience to reread the past. The haptic and dialectical approach to the past allows to build images that operate as spaces of experience for the viewer, generating a temporality that evokes the experience of historical time, but also generates a new vision of the present. Through this look at history and its cinematic reconstructions we explore the temporalities that are generated, both in historical writing through images and in its encounter with the audience.
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Babaniyi, Olalekan Adeoye. "Direct elastic modulus reconstruction via sparse relaxation of physical constraints." Thesis, 2012. https://hdl.handle.net/2144/17151.
Full textAbstract:
Biomechanical imaging (BMI) is the process of non-invasively measuring the spatial
distribution of mechanical properties of biological tissues. The most common
approach uses ultrasound to non-invasively measure soft tissue deformations. The
measured deformations are then used in an inverse problem to infer local tissue mechanical
properties. Thus quantifying local tissue mechanical properties can enable
better medical diagnosis, treatment, and understanding of various diseases.
A major difficulty with ultrasound biomechanical imaging is getting accurate measurements
of all components of the tissue displacement vector field. One component
of the displacement field, that parallel to the direction of sound propagation, is typically
measured accurately and precisely; the others are available at such low precision
that they may be disregarded in the first instance. If all components were available at
high precision, the inverse problem for mechanical properties could be solved directly,
and very efficiently. When only one component is available, the inverse problem solution
is necessarily iterative, and relatively speaking, computationally inefficient.
The goal of this thesis, therefore, is to develop a processing method that can be
used to recover the missing displacement data with sufficient precision to allow the
direct reconstruction of the linear elastic modulus distribution in tissue. This goal
was achieved by using a novel spatial regularization to adaptively enforce and locally
relax a special form of momentum conservation on the measured deformation field.
The new processing method was implemented with the Finite Element Method
(FEM). The processing method was tested with simulated data, measured data from
a tissue mimicking phantom, and in-vivo clinical data of breast masses, and in all
cases it was able to recover precise estimates the full 2D displacement and strain fields.
The recovered strains were then used to calculate the material property distribution
directly.
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Hung, Te-Sheng, and 洪德昇. "The Development of Spectral Phase Interferometry for Direct Electric-Field Reconstruction." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/57357208988984719719.
Full textAbstract:
碩士國立中正大學
物理所
94
This thesis describes the development to the spectral phase interferometry for direct electric field reconstruction (SPIDER). We first develop a program to simulate the trace of a pulse on the spectral interferogram and retrieve the spectral phase base on a Fourier transform algorithm. We also build a SPIDER apparatus to measure the phase of a pulse from a CPA (chirped-pulse amplification) laser system by employing the algorithm developed. Finally, we calibrate the SPIDER system by calculating the dispersion induced by changing the distance of two gratings in a compressor system and compare the results to that measured by the SPIDER system.