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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Polígono de Newton de una foliación de tipo curva generalizada / Polígono de Newton de una foliación de tipo curva generalizada

Fernández, Percy, Saravia, Nancy 25 September 2017 (has links)
Generalized curve foliations are a type of foliations that have a similar reduction as the one given by curves. Camacho, Lins Neto, and Sad showed that generalized curve no-dicritical foliations have the same reduction of singularities than their separatrices. In this paper we give a novel proof of Dulac's theorem ([9]) using techniques of Rouille ([19]). This theorem shows that for generalized curve no-dicritical foliations their Newton polygons and their separatrices are equal. Using Dulac's theorem we return to a result (wrongly) stated by Loray, which is notquite right, as noticed by Fernandez, Mozo and, Neciosup. / Foliaciones de tipo curva generalizada son una clase de foliaciones que tienen una reducción de singularidades similar a la que existe para curvas. Camacho, Lins Neto and Sad mostraron que aquellas que son no dicríticas tienen la misma reducción que la de su conjunto de separatrices. En este artículo presentamos una prueba novedosa del teorenma de Dulac utilizando técnicas de Rouillé. Este teorema muestra que para foliaciones no dicríticas de tipo curva generalizada su polígono de Newton y el su conjunto de sepatrices coinciden. Mediante el teorema de Dulac retornamos a un resultado conjeturado por Loray que no es del todo cierto, como fue anotado por Fernández, Mozo y Neciosup.
92

L'éclatement générique et l'imaginaire des formes géométriques dans les oeuvres de Kateb Yacine / The generic bursting and the imagination of geometrics forms in the works of Kateb Yacine

Medadjelia, Mohammed Ramzi 13 December 2016 (has links)
Kateb Yacine est un écrivain qui suscite des questionnements et mystères quant à la portée sémantique et structurelle de ses écrits. Porte-étendard de la conscience insoumise, son oeuvre est une tentative de reconstitution du passé à travers une écriture engagée, propre à penser et à agir debout. Son oeuvre se trouve au carrefour d’obsessions personnelles, de mythes collectifs et de l’histoire millénaire de l’Algérie. Sa vie même se recompose au sein de ses oeuvres marquées par l’éclatement poétique. le personnage de Nedjma qui est tout au plus une figure constante dans l'imaginaire katébien, suggère la forme géométrique de l'étoile comme une sorte d'alternative au mouvement concentrique de la temporalité narrative. L'éclatement des formes passe passe résolument par l'étoile qui concentre en elle la passion amoureuse, la pésie, le mythe et l'histoire. La figure de Nedjma a permis à Kateb d'exterioriser la complexité de ses débats personnels ainsi collectifs, en les approfondissant / Kateb Yacine is a writer who sparks questions and mysteries about the semantic and structural scope of his writings. Flagship of the rebellious conscience, his works is an attempt to rebuild the past trough engaged writing, able to think and to act up. His work lies at the crossroads of personal obsessions, collective myths and ancient history of Algeria. His life even decomposes in his works marked by poetic burst. the character of Nedjma is at most a constant figure of Katebian imaginary, suggests the geometric shape of the star as an alternative of the concentric motion of narrative temporality. The explosion of forms is resolutely through the star which concentrates in itself passionate love, poetry, myth and history. Nedjma figure allowed Kateb externalizing and deepening the complexity of his personal and collective discussions
93

Aplicacao de determinante: area de poligono convexo e volume de piramide / Determinants of application: convex polygon area and volume of pyramid

Araujo, Elismar Jose de 17 June 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-22T14:36:33Z No. of bitstreams: 2 Dissertação - Elismar Jose de Araujo - 2015.pdf: 3923576 bytes, checksum: 60a5b973a48070a14372679c6aa08221 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-22T14:39:53Z (GMT) No. of bitstreams: 2 Dissertação - Elismar Jose de Araujo - 2015.pdf: 3923576 bytes, checksum: 60a5b973a48070a14372679c6aa08221 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-22T14:39:53Z (GMT). No. of bitstreams: 2 Dissertação - Elismar Jose de Araujo - 2015.pdf: 3923576 bytes, checksum: 60a5b973a48070a14372679c6aa08221 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-06-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work will concentrate on making a rereading of the theories that surround the procedures for calculating the area of a convex polygon, as well as the volume of a pyramid whose base is a polygon convex, with its vertices properly represented in a coordinate system, in the plan or in space, respectively. Addresses some topics on arrays and determinant and some of its applications, in particular the study of polygon area and the volume of the pyramid. Based on applying a decisive factor for the calculation of the area of a triangle with its vertices represented in a coordinate system, presents a new theorem to calculate the area of any polygon convex, as well as, a new formula to calculate the volume of any pyramid with convex basis as a direct application of the volume of the tetrahedron with its vertices represented in an orthogonal system. For both, it was essential to the concept of coordinates in the plane and in space, vectors in the plane and in space, and some of its properties, being essential for the demonstrate the volume of the tetrahedron and the area of the triangle, using determinant. Keywords: Volume. Area. Convex polygon. Pyramid. Triangle. Tetrahedron / O presente trabalho versar a em fazer uma releitura das teorias que circundam os procedimentos de c alculo da area de um pol gono convexo, assim como, do volume de uma pir^amide cuja base e um pol gono convexo, com seus v ertices devidamente representados em um sistema de coordenadas, no plano ou no espa co, respectivamente. Aborda alguns t opicos sobre matrizes e determinante e algumas de suas aplica c~oes, em especial o estudo de area de pol gonos e o volume de pir^amide. Baseado na aplica c~ao de determinante para o c alculo da area de um tri^angulo com seus v ertices representados em um sistema de coordenadas, apresenta um novo teorema para o c alculo da area de qualquer pol gono convexo, assim como, uma nova f ormula para calcular o volume de qualquer pir^amide com base convexa como uma aplica c~ao direta do volume do tetraedro com seus v ertices representados em um sistema ortogonal. Para tanto, foi imprescind vel abordar o conceito de coordenadas no plano e no espa co, vetores no plano e no espa co e algumas de suas propriedades, sendo fundamentais para a demonstrar o volume do tetraedro e a area do tri^angulo, usando determinante.
94

Régression bayésienne sous contraintes de régularité et de forme. / Bayesian regression under shape and smoothness restriction.

Khadraoui, Khader 08 December 2011 (has links)
Nous étudions la régression bayésienne sous contraintes de régularité et de forme. Pour cela,on considère une base de B-spline pour obtenir une courbe lisse et nous démontrons que la forme d'une spline engendrée par une base de B-spline est contrôlée par un ensemble de points de contrôle qui ne sont pas situés sur la courbe de la spline. On propose différents types de contraintes de forme (monotonie, unimodalité, convexité, etc). Ces contraintes sont prises en compte grâce à la loi a priori. L'inférence bayésienne a permis de dériver la distribution posteriori sous forme explicite à une constante près. En utilisant un algorithme hybride de type Metropolis-Hastings avec une étape de Gibbs, on propose des simulations suivant la distribution a posteriori tronquée. Nous estimons la fonction de régression par le mode a posteriori. Un algorithme de type recuit simulé a permis de calculer le mode a posteriori. La convergence des algorithmes de simulations et du calcul de l'estimateur est prouvée. En particulier, quand les noeuds des B-splines sont variables, l'analyse bayésienne de la régression sous contrainte devient complexe. On propose des schémas de simulations originaux permettant de générer suivant la loi a posteriori lorsque la densité tronquée des coefficients de régression prend des dimensions variables. / We investigate the Bayesian regression under shape and smoothness constraints. We first elicita Bayesian method for regression under shape restrictions and smoothness conditions. Theregression function is built from B-spline basis that controls its regularity. Then we show thatits shape can be controlled simply from its coefficients in the B-spline basis. This is achievedthrough the control polygon whose definition and some properties are given in this article.The regression function is estimated by the posterior mode. This mode is calculated by asimulated annealing algorithm which allows to take into account the constraints of form inthe proposal distribution. A credible interval is obtained from simulations using Metropolis-Hastings algorithm with the same proposal distribution as the simulated annealing algorithm.The convergence of algorithms for simulations and calculation of the estimator is proved. Inparticular, in the case of Bayesian regression under constraints and with free knots, Bayesiananalysis becomes complex. we propose original simulation schemes which allows to simulatefrom the truncated posterior distribution with free dimension.
95

Software pro efektivní využití materiálu při 2D obrábění / Software for efficient use of material in 2D machining

Švanda, Ondřej January 2020 (has links)
Tato práce si klade za cíl obeznámit čtenáře s 2D CNC obráběním a rozličnými metodami popisu a manipulace s dvojrozměrnými objekty. Poté je představen tzv. Nesting problém a jsou popsány různé metody přístupu k jeho vyřešení. Praktická část pokrývá implementaci vlastního nesting softwaru, jenž je schopný efektivně rozmístit nepravidelné tvary do nepravidelné ohraničené plochy. Na závěr je provedeno zhodnocení řečeného softwaru a také je zmíněno jeho možné využití v praxi.
96

Tvorba 3D modelu čelistního kloubu / Creating 3D Model of Temporomandibular Joint

Šmirg, Ondřej January 2015 (has links)
The dissertation thesis deals with 3D reconstruction of the temporomandibular joint from 2D slices of tissue obtained by magnetic resonance. The current practice uses 2D MRI slices in diagnosing. 3D models have many advantages for the diagnosis, which are based on the knowledge of spatial information. Contemporary medicine uses 3D models of tissues, but with the temporomandibular joint tissues there is a problem with segmenting the articular disc. This small tissue, which has a low contrast and very similar statistical characteristics to its neighborhood, is very complicated to segment. For the segmentation of the articular disk new methods were developed based on the knowledge of the anatomy of the joint area of the disk and on the genetic-algorithm-based statistics. A set of 2D slices has different resolutions in the x-, y- and z-axes. An up-sampling algorithm, which seeks to preserve the shape properties of the tissue was developed to unify the resolutions in the axes. In the last phase of creating 3D models standard methods were used, but these methods for smoothing and decimating have different settings (number of polygons in the model, the number of iterations of the algorithm). As the aim of this thesis is to obtain the most precise model possible of the real tissue, it was necessary to establish an objective method by which it would be possible to set the algorithms so as to achieve the best compromise between the distortion and the model credibility achieve.
97

Vektorová analýza v GIS systémech / Vector Analysis in GIS Systems

Životský, Tomáš January 2015 (has links)
This master's thesis deals with the geographic information systems   with an emphasis on so - called vector analysis . The aim of the thesis is to create a library that implements the internal representation   of geographic data and performs analytical operation over them .  The thesis describes the logical structure of the application and the hierarchy of abstract classes . In the form of pseudo -code is shown a set of individual computing operations . Work is strongly based on geographic system GRASS. This GIS is connectable through  import and export vector data in shapefile format. Concept of   storing layers is designed for ease of data manipulation and  their portability . The main idea behind the application is to split the library into individual modules . These modules are  independent , but also can benefit from each other's functions . In conclusion are demonstrated implemented vector analysis and  representation of their calculation .
98

Faktorizacija polinoma dve promenljive sa celobrojnim koeficijentima pomoću Newton-ovog poligona i primena u dekodiranju nekih klasa Reed – Solomon kodova / Factoring bivariate polynomials with integer coefficients via Newton polygon and its application in decoding of some classes of Reed – Solomon codes

Pavkov Ivan 29 September 2107 (has links)
<p>Predmet istraživanja doktorske disertacije je faktorizacija polinoma dve promenljive sa celobrojnim koeficijentima pomoću njima pridruženih Newton-ovih poligona. Formalizacija potrebnog i dovoljnog uslova za postojanje netrivijalne faktorizacije polinoma dve promenljive sa celobrojnim koeficijentima omogućava konstrukciju efektivnog algoritma za faktorizaciju. Konačno, dobijeni teorijski rezultati su primenjeni na dekodiranje jedne klase Reed &ndash; Solomon kodova, miksa dve kodne reči.</p> / <p>The research subject of the thesis is factorization of bivariate polynomials with integer coefficients via associated Newton polygons. Formalization of the necessary and sufficient condition for the existence of a non &ndash; trivial factorization of an arbitrary bivariate polynomial with integer coefficients obtains theoretical basis for construction of an effective factorization algorithm. Finally, these theoretical results are applied in decoding special class of Reed &ndash; Solomon codewords, mixture of two codewords.</p>
99

Echtzeit-Visualisierung von sehr großen Virtual- und Augmented-Reality-Szenen auf Smartphones und mobilen Tablet-Computern

Färber, Markus, Ghiletiuc, Johannes, Schwarz, Peter, Brüderlin, Beat January 2012 (has links)
Aus der Einleitung: "Klassische VR/AR-Ausgabegeräte sind meist kopfgetragene Systeme oder 3D-Projektionsanlagen. In bestimmten Anwendungsfällen, zum Beispiel in der Wartung (Schreiber 2011) oder auch in Bauplanung und Bauausführung (Woodward 2011), verbieten sich diese Geräte aufgrund von Arbeitsschutzbestimmungen oder widrigen Einsatzbedingungen. Hier bieten sich Smartphones oder auf ähnlicher Technologie arbeitende Tablett-Computer als Alternative an, insbesondere dann, wenn stereoskopische Darstellung nicht benötigt wird."
100

Exploring procedural generation of buildings

Täljsten, David January 2020 (has links)
This thesis explores the procedural generation of 3D buildings from the floor plan all the way to the fa¸cade and building’s details such as doors, windows, and roof. Through this, the study explores several techniques and approaches to create different layers of the building generation pipeline. The focus is on implementing a set of algorithms that, when running sequentially, are able to create complete 3D buildings in a short time (so they can be used in online generation), could be used in any open-world game, and with a limited count of triangles per building. Furthermore, the tool provides a clear and easy-to-use interface for designers in Unity, where they can interact with the multiple parameters of each building layer, giving designers a high degree of controllability. The tool is evaluated using the resulting buildings based on different metrics and how individual changes to different parameter starting from a template affect the output of the generator in terms of the metrics and the resulting building. The result from the analysis show that the polygon mathematics is well suited for generating 3D buildings for games.

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