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Detekce elipsy v obraze / Ellipse DetectionHříbek, Petr January 2008 (has links)
The thesis introduces methods used for an ellipse detection. Each method is theoretically described in current subsection. The description includes methods like Hough transform, Random Hough transform, RANSAC, Genetic Algorithm and improvements with optimalization. Further there are described modifications of current procedures in the thesis to reach better results. Next to the last chapter represents testing parameters of speed, quality and accuracy of implemented algorithms. There is a conclusion of testing and a result discussion at the end.
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Spatial Analysis of Rock TexturesBasnet, Shiva 16 October 2012 (has links)
No description available.
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Metrical Problems in Minkowski GeometryFankhänel, Andreas 19 October 2012 (has links) (PDF)
In this dissertation we study basic metrical properties of 2-dimensional normed linear spaces, so-called (Minkowski or) normed planes.
In the first chapter we introduce a notion of angular measure, and we investigate under what conditions certain angular measures in a Minkowski plane exist. We show that only the Euclidean angular measure has the property that in an isosceles triangle the base angles are of equal size. However, angular measures with the property that the angle between orthogonal vectors has a value of pi/2, i.e, a quarter of the full circle, exist in a wider variety of normed planes, depending on the type of orthogonality. Due to this we have a closer look at isosceles and Birkhoff orthogonality. Finally, we present results concerning angular bisectors.
In the second chapter we pay attention to convex quadrilaterals. We give definitions of different types of rectangles and rhombi and analyse under what conditions they coincide. Combinations of defining properties of rectangles and rhombi will yield squares, and we will see that any two types of squares are equal if and only if the plane is Euclidean. Additionally, we define a ``new\'\' type of quadrilaterals, the so-called codises. Since codises and rectangles coincide in Radon planes, we will explain why it makes sense to distinguish these two notions. For this purpose we introduce the concept of associated parallelograms.
Finally we will deal with metrically defined conics, i.e., with analogues of conic sections in normed planes. We define metric ellipses (hyperbolas) as loci of points that have constant sum (difference) of distances to two given points, the so-called foci. Also we define metric parabolas as loci of points whose distance to a given point equals the distance to a fixed line. We present connections between the shape of the unit ball B and the shape of conics. More precisely, we will see that straight segments and corner points of B cause, under certain conditions, that conics have straight segments and corner points, too. Afterwards we consider intersecting ellipses and hyperbolas with identical foci. We prove that in special Minkowski planes, namely in the subfamily of polygonal planes, confocal ellipses and hyperbolas intersect in a way called Birkhoff orthogonal, whenever the respective ellipse is large enough.
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AJUSTAMENTO DE LINHA POLIGONAL NO ELIPSÓIDE / TRAVERSE ADJUSTMENT IN THE ELLIPSOIDBisognin, Márcio Giovane Trentin 26 April 2006 (has links)
Traverses Adjustment in the surface of the ellipsoid with the objectives to guarantee
the solution unicity in the transport of curvilinear geodesic coordinates (latitude and
longitude) and in the azimuth transport and to get the estimates of quality. It deduces
the coordinate transport and the azimuth transport by mean Legendre s series of the
geodesic line. This series is based on the Taylor s series, where the argument is the
length of the geodesic line. For the practical applications, it has the necessity to
effect the truncation of the series and to calculate the function error for the latitude,
the function error for the longitude and the function error for the azimuth. In this
research, these series are truncated in the derivative third and calculates the express
functions error in derivative fourth. It is described the adjustment models based on
the least-squares method: combined model with weighted parameters, combined
model or mixed model, parametric model or observations equations and correlates
model or condition equations model. The practical application is the adjustment by
mean parametric model of a traverse measured by the Instituto Brasileiro de
Geografia e Estatística (IBGE), constituted of 8 vertices and the 129.661 km length.
The localization of errors in the observations is calculated by the Baarda s data
snooping test in the last iteration of the adjustment that showed some observations
with error. The estimates of quality are in the variance-covariance matrices and
calculate the semiaxes of the error ellipse or standard ellipse of each point by means
of the spectral decomposition (or Jordan s decomposition) of the submatrices of the
variance-covariance matrix of the adjusted parameters (the coordinates). It is
important to note that the application of the Legendre s series is satisfactory for short
distances until 40km length. The convergence of the series is fast for the adjusted
coordinates, where the stopped criterion of the iterations is four decimals in the
sexagesimal second arc, where it is obtained from interation second of the
adjustment. / Ajustamento de linhas poligonais na superfície do elipsóide com os objetivos de
garantir a unicidade de solução no transporte de coordenadas geodésicas
curvilíneas (latitude ϕ e longitude λ ) e no transporte de azimute e de obter as
estimativas de qualidade. Deduz o transporte de coordenadas e o transporte de
azimute pelas séries de Legendre da linha geodésica. Essa série se fundamenta na
série de Taylor, em que o argumento é o comprimento da linha geodésica. Para as
aplicações práticas, há a necessidade de efetuar o truncamento da série e calcular a
função erro para a latitude, função erro para a longitude e função erro para o
azimute. Nesta pesquisa, trunca-se a série na derivada terceira e calculam-se as
funções erro expressas em derivada quarta. Expõe os modelos de ajustamento
fundamentados no método dos mínimos quadrados (MMQ): modelo combinado com
ponderação aos parâmetros, modelo combinado ou implícito, modelo paramétrico ou
das equações de observação e modelo dos correlatos ou das equações de
condição. A aplicação prática é o ajustamento pelo modelo paramétrico de uma linha
poligonal medida pelo Instituto Brasileiro de Geografia e Estatística (IBGE),
constituída de 8 vértices e de comprimento igual a 129,661 km. A localização de
erros nas observações é efetuada pelo teste data snooping de Baarda na última
etapa do ajustamento que mostrou algumas observações com erro. As estimativas
de qualidade estão nas matrizes variância-covariância (MVC) e calcula-se os semieixos
da elipse dos erros (ou elipse padrão) de cada ponto mediante a
decomposição espectral (ou decomposição de Jordan) das submatrizes da MVC dos
parâmetros (as coordenadas) ajustados. Mostra-se que a aplicação das séries de
Legendre é satisfatória para distâncias curtas até 40km. A convergência da série é
rápida para as coordenadas ajustadas, onde o critério de parada das iterações seja
quatro decimais do segundo de arco em que se atingiu na segunda etapa do
ajustamento.
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Metrical Problems in Minkowski GeometryFankhänel, Andreas 07 June 2012 (has links)
In this dissertation we study basic metrical properties of 2-dimensional normed linear spaces, so-called (Minkowski or) normed planes.
In the first chapter we introduce a notion of angular measure, and we investigate under what conditions certain angular measures in a Minkowski plane exist. We show that only the Euclidean angular measure has the property that in an isosceles triangle the base angles are of equal size. However, angular measures with the property that the angle between orthogonal vectors has a value of pi/2, i.e, a quarter of the full circle, exist in a wider variety of normed planes, depending on the type of orthogonality. Due to this we have a closer look at isosceles and Birkhoff orthogonality. Finally, we present results concerning angular bisectors.
In the second chapter we pay attention to convex quadrilaterals. We give definitions of different types of rectangles and rhombi and analyse under what conditions they coincide. Combinations of defining properties of rectangles and rhombi will yield squares, and we will see that any two types of squares are equal if and only if the plane is Euclidean. Additionally, we define a ``new\'\' type of quadrilaterals, the so-called codises. Since codises and rectangles coincide in Radon planes, we will explain why it makes sense to distinguish these two notions. For this purpose we introduce the concept of associated parallelograms.
Finally we will deal with metrically defined conics, i.e., with analogues of conic sections in normed planes. We define metric ellipses (hyperbolas) as loci of points that have constant sum (difference) of distances to two given points, the so-called foci. Also we define metric parabolas as loci of points whose distance to a given point equals the distance to a fixed line. We present connections between the shape of the unit ball B and the shape of conics. More precisely, we will see that straight segments and corner points of B cause, under certain conditions, that conics have straight segments and corner points, too. Afterwards we consider intersecting ellipses and hyperbolas with identical foci. We prove that in special Minkowski planes, namely in the subfamily of polygonal planes, confocal ellipses and hyperbolas intersect in a way called Birkhoff orthogonal, whenever the respective ellipse is large enough.:1 Introduction
2 On angular measures
3 Types of convex quadrilaterals
4 On conic sections
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Méthodes rapides et efficaces pour la résolution numérique d'équations de type Hamilton-Jacobi avec application à la simulation de feux de forêtDesfossés Foucault, Alexandre 10 1900 (has links)
Cette thèse est divisée en trois chapitres. Le premier explique comment utiliser la méthode «level-set» de manière rigoureuse pour
faire la simulation de feux de forêt en utilisant comme modèle physique pour la propagation le modèle de l'ellipse de Richards. Le second
présente un nouveau schéma semi-implicite avec une preuve de convergence pour la solution d'une équation de type Hamilton-Jacobi
anisotrope. L'avantage principal de cette méthode est qu'elle permet de réutiliser des solutions à des problèmes «proches» pour
accélérer le calcul. Une autre application de ce schéma est l'homogénéisation. Le troisième chapitre montre comment utiliser les méthodes
numériques des deux premiers chapitres pour étudier l'influence de variations à petites échelles dans la vitesse du vent sur la propagation
d'un feu de forêt à l'aide de la théorie de l'homogénéisation. / This thesis is divided in three chapters. The first explains how to use the level-set method in a rigorous way in the context of forest fire simulation when the physical
propagation model for firespread is Richards' ellipse model. The second chapter presents a new semi-implicit scheme with a proof of convergence for the numerical solution of an
anisotropic Hamilton-Jacobi partial differential equation. The advantage of this scheme is it allows the use of approximative solutions as initial conditions which reduces the
computation time. The third chapter shows how to use the tools introduced in the first two chapters to study the influence of small-scale variations on the wind speed on
firespread using the theory of homogenization.
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Pedagogika a škola Marie Montessori v České republice / Pedagogy and school of Maria Montessori in the Czech republicGlaserová, Barbora January 2012 (has links)
This thesis "Pedagogy and Maria Montessori School in the Czech Republic" in the theoretical part describes the life of Maria Montessori, Montessori principles of education and development of Montessori schools with a focus on their development in the Czech Republic. The practical part deals with a case study of a Prague school with Montessori principles and a questionnaire survey with the headmaster of Montessori schools.
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Photogrammetric techniques for characterisation of anisotropic mechanical properties of Ti-6Al-4VArthington, Matthew Reginald January 2010 (has links)
The principal aims of this research have been the development of photogrammetric techniques for the measurement of anisotropic deformation in uniaxially loaded cylindrical specimens. This has been achieved through the use of calibrated cameras and the application of edge detection and multiple view geometry. The techniques have been demonstrated at quasi-static strain rates, 10^-3 s^-1, using a screw-driven loading device and high strain rates, 10^3 s^-1, using Split Hopkinson Bars. The materials that have been measured using the technique are nearlyisotropic steel, anisotropic cross-rolled Ti-6Al-4V and anisotropic clock-rolled commercially pure Zr. These techniques allow the surface shapes of specimens that deform elliptically to be completely tracked and measured in situ during loading. This has allowed the measurement of properties that could not have been recorded before, including true direct stress and the ratio of transverse strains in principal material directions, at quasi-static and elevated strain rates, in tension and compression. The techniques have been validated by measuring elliptical prisms of various aspect ratios and independently measuring interrupted specimens using a coordinate measurement machine. A secondary aim of this research has been to improve the characterisation of the anisotropic mechanical properties of cross-rolled Ti-6Al-4V using the techniques developed. In particular, the uniaxial yield stresses, hardening properties and the associated anisotropic deformation behaviour along the principal material directions, have all been recorded in detail not seen before. Significant findings include: higher yield stresses in-plane than in the through-thickness direction in both tension and compression, and the near transverse-isotropy of the through-thickness direction for loading conditions other than quasi-static tension, where significant anisotropy was observed.
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Uniform Marker Field na válci / Uniform Marker Field on a CylinderKříž, Radim January 2013 (has links)
This work presents a new extension for Uniform Marker Field, which is able to detect UMF on the cylinder. First part of the text deals with Augmented reality and focuses on systems using markers. It discusses the actual state-of-the-art systems and its possibilities. After that it focuses more deeply on the marker system Uniform marker field and its grayscale variants. Next part of the work describes properties of the cylinder projected in real space. Important properties for detecting are discussed in detail. Then the proposal and description of detection algorithm is presented. Implementation of algorithm is tested and evaluated on the very end of this thesis.
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