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Now showing items 21-30 of 63

#### Fully transitive polyhedra with crystallographic symmetry groups

(1990)

This dissertation sets forth a method for classifying, up to euclidean similarity, fully-transitive polyhedra which have crystallographic symmetry groups. Branko Grunbaum's definition of polyhedron is used, in which the ...

#### Multilevel algorithms for nonlinear equations and equality constrained optimization

(1993)

A general trust region strategy is proposed for solving nonlinear systems of equations and equality constrained optimization problems by means of multilevel algorithms. The idea is to use the trust region strategy to ...

#### Invariants of graphs

(1993)

We define an infinite sequence of invariants $\bar\mu\sb{K}$ of connected, finite graphs K. These invariants detect whether or not a "longitude" associated to a cycle in K lies in the $n\sp{th}$ term of the lower central ...

#### Microlocal regularity of an inverse problem for the multidimensional wave equation

(1991)

Many physical processes such as reflection seismology, oil exploration, and ground-penetrating radar may be modeled as inverse problems for the multidimensional acoustic wave equation with point energy sources. The inverse ...

#### Regularity of minimizing maps and flows various functionals and targets

(1996)

This thesis discusses regularity problems of minimizing maps and flows for various functionals and targets. It consists of four parts:
Part 1. Energy Minimizing Mappings into Polyhedra. We prove both the partial interior ...

#### On the boundaries of special Lagrangian submanifolds

(1995)

An n-dimensional submanifold M in ${\bf C}\sp{n} = {\bf R}\sp{2n}$ is called Lagrangian if the restriction of $\omega$ to M is zero, where $\omega = \Sigma{\limits\sb{i}}dz\sb{i}\ \wedge\ d\bar z\sb{i}$. It is called special ...

#### A variational approach to the local uniqueness of minimal surfaces immersed in R(3)

(1998)

In the past 20 years, many techniques have been developed for proving the existence of complete minimal surfaces immersed in space. Few methods are known for classifying such surfaces. In order to study the structure of ...

#### Homology boundary links, patterns, and Seifert forms

(1996)

Homology boundary links have become an increasingly important class of links, largely due to their significance in the ongoing concordance classification of links. Tim Cochran and Jerome Levine defined an algebraic object ...

#### Fuchsian groups and polygonal billiards

(1996)

Let P be a simple, closed polygon in the plane, all interior angles of which are rational multiples of $\pi$. We consider the possible paths of a point, rebounding in the interior of P with constant speed and elastic ...

#### A restarted Lanczos process for computing a large percentage of the eigenvalues of a symmetric matrix

(1996)

The Lanczos algorithm is a well known technique for approximating a few eigenvalues and corresponding eigenvectors of a large-scale real symmetric matric arising in many scientific and engineering applications.
In this ...