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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.
171

Kompatibilitätsanalyse dynamischen Verhaltens von integrierten Automobil-Steuergeräten

Glockner, Matthias, Hardt, Wolfram, Fuchs, Maximilian, Macht, Michael 08 June 2007 (has links) (PDF)
In Premium-Fahrzeugen werden derzeit ca. 60-70 Steuergeräte (SG) verbaut. Steuergeräte sind „eingebettete Systeme“ und stellen die zentralen Rechen- und Steuereinheiten für die elektrischen und elektronischen Systeme im Fahrzeug dar. Mit Hilfe der Steuergeräte, die über Bus-Systeme (z.B. CAN-Bus) miteinander vernetzt sind, können komplexe Funktionen realisiert werden. Das Motor- Steuergerät ist eines der bekanntesten. Der steigende Innovationsgrad im Elektrik- / Elektronik- Umfeld zwingt die Autohersteller, in immer kürzeren Zeitabständen, neue Steuergeräte mit höherer Rechenleistung und neuen Funktionen zu entwickeln. Aufgrund der steigenden Anzahl von Steuergeräten, spielt deren Rückwärtskompatibilität eine immer wichtigere Rolle.
172

The Geometry of Regular Trees with the Faber-Krahn Property

Leydold, Josef January 1998 (has links) (PDF)
In this paper we prove a Faber-Krahn-type inequality for regular trees and give a complete characterization of extremal trees. It extends a former result of the author. The main tools are rearrangements and perturbation of regular trees. (author's abstract) / Series: Preprint Series / Department of Applied Statistics and Data Processing
173

Hipersuperficies generalizadas en Cn / Hipersuperficies generalizadas en Cn

Fernandez Sánchez, Percy, Mozo Fernández, Jorge, Neciosup Puican, Hernán 25 September 2017 (has links)
The main aim of this paper is proof that the reduction of the singularities of a generalized hypersurfaces agrees with a reduction of singularities of its separatrix; which is a generalization of the result presented in [8] by the first two authors. / El objetivo principal de este artículo es demostrar que la reduccióon de singularidades de una hipersupercie generalizada coincide con una reducción de singularidades de su separatriz; el cual es una generalización del resultado presentado en [8] por los dos primeros autores.
174

Medida aleatoria de Poisson / Medida aleatoria de Poisson

Beltrán, Johel 25 September 2017 (has links)
In this monograph we continue with the inspection initiated in [1] on the fundamental tools introduced in the approach proposed in [2,3] for the study of metastability. We give the definition of the Poisson random measures and prove the main properties that we will subsequently use to construct Markov processes with finite state space. Such construction will allow us to provide a probabilistic proof of the fact that the law of a Markov process solves the martingal problem. / En esta monografía continuamos con el desarrollo iniciado en [1] sobre las herramientas fundamentales usadas en el abordaje propuesto en [2,3] para el estudio de la metaestabilidad. Definimos las medidas aleatorias de Poisson y probamos las principales propiedades que seran usadas para construir procesos de Markov con espacio de estados finito. Esta forma de abordar la propiedad Markoviana nos permitirá dar una demostración probabilística de que la ley de un proceso de Markov resuelve un problema martingala.
175

Clasificación de foliaciones elípticas inducidas por campos cuadráticos reales con centro / Clasificación de foliaciones elípticas inducidas por campos cuadráticos reales con centro

Puchuri, Liliana 25 September 2017 (has links)
Embedded in the study of Hilbert's innitesimal problem is the question of existence and number of limit cycles of linear perturbations of Hamiltonian fields. Since there is available a classication of real quadratic fields with center in R2, we can match them with complex fields in C2 that induce a foliation in P2. Our objective is to classify the foliations in P2 induced by the elds obtained by said classication of quadratic fields with center which are elliptic brations, that is, the ones with level curves of genus one. / En el estudio del problema infinitesimal de Hilbert se encuentra inmersa la tarea de analizar la existencia y de acotar el número de ciclos límite de una perturbación lineal de campos hamiltonianos. Como existe una clasificación de campos cuadráticos reales con centro en R2, podemos asociar campos complejos en C2 que inducen una foliación en P2. El objetivo de este trabajo es clasificar aquellas foliaciones en P2 inducidas por estos campos cuadráticos que sean fibraciones elípticas, es decir, aquellas cuyas curvas de nivel sean de género uno.
176

Hypersato Structures / Hypersato Structures

Cuadros Valle, Jaime 25 September 2017 (has links)
We define hypersato structures: these structures admit three inequivalent Sasakian structures such that each of these structures shares a common Reeb vector field and a common contact form with the others two. It is interestingto notice that hypersato manifolds can be viewed as U(1) principal orbibundles with base space a 4n-dimensional hyperkahler orbifold. We also discuss some results on the moduli problem of these structures. / Definimos variedades hipersato: estas variedades admiten tres estructuras del tipo Sasaki inequivalentes de tal manera que estas tres estructuras poseen un campo vectorial del tipo Reeb y una forma de contacto en común. Variedades que admiten estructura hipersato pueden considerarse como espacios totales de un fibrado principal U(1) del tipo orbifold, donde el espacio base admite una métrica singular hiperkahler. Discutimos tambien algunos resultados acerca del espacio moduli de variedades admitiendo estas estructuras.
177

Un teorema de tipo Bott para orbifolds complejos y aplicaciones / Un teorema de tipo Bott para orbifolds complejos y aplicaciones

Rodríguez, A. Miguel 25 September 2017 (has links)
We present (without proof) a version of Bott theorem for compact complex orbifolds with isolated singularities. Then we deduce some important consequences of this theorem, and nally we give some applications to holomorphic foliations on weighted projective spaces. / Presentamos (sin demostración) una versión del teorema de Bott para un orbifold complejo compacto y con singularidades aisladas. A continuación deducimos algunas consecuencias importantes de este teorema, y finalmente daremos algunas aplicaciones para foliaciones holomorfas en espacios proyectivos ponderados.
178

Ein Residuenfehlerschätzer für anisotrope Tetraedernetze und Dreiecksnetze in der Finite-Elemente-Methode

Kunert, G. 30 October 1998 (has links) (PDF)
Some boundary value problems yield anisotropic solutions, e.g. solutions with boundary layers. If such problems are to be solved with the finite element method (FEM), anisotropically refined meshes can be advantageous. In order to construct these meshes or to control the error one aims at reliable error estimators. For isotropic meshes such estimators are known but they fail when applied to anisotropic meshes. Rectangular (or cuboidal) anisotropic meshes were already investigated. In this paper an error estimator is presented for tetrahedral or triangular meshes which offer a much greater geometrical flexibility.
179

Newtons method with exact line search for solving the algebraic Riccati equation

Benner, P., Byers, R. 30 October 1998 (has links) (PDF)
This paper studies Newton's method for solving the algebraic Riccati equation combined with an exact line search. Based on these considerations we present a Newton{like method for solving algebraic Riccati equations. This method can improve the sometimes erratic convergence behavior of Newton's method.
180

HAMEV and SQRED: Fortran 77 Subroutines for Computing the Eigenvalues of Hamiltonian Matrices Using Van Loanss Square Reduced Method

Benner, P., Byers, R., Barth, E. 30 October 1998 (has links) (PDF)
This paper describes LAPACK-based Fortran 77 subroutines for the reduction of a Hamiltonian matrix to square-reduced form and the approximation of all its eigenvalues using the implicit version of Van Loan's method. The transformation of the Hamilto- nian matrix to a square-reduced Hamiltonian uses only orthogonal symplectic similarity transformations. The eigenvalues can then be determined by applying the Hessenberg QR iteration to a matrix of half the order of the Hamiltonian matrix and taking the square roots of the computed values. Using scaling strategies similar to those suggested for algebraic Riccati equations can in some cases improve the accuracy of the computed eigenvalues. We demonstrate the performance of the subroutines for several examples and show how they can be used to solve some control-theoretic problems.

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