Network maintenance July 27th between 7:30AM and 8:00AM CDT may cause service disruptions.

  You limited your search to:

  Partner: UNT Libraries
 Degree Discipline: Mathematics
 Collection: UNT Theses and Dissertations
The History of the Calculus

The History of the Calculus

Date: 1945
Creator: Ashburn, Andrew
Description: The purpose of this essay is to trace the development of the concepts of the calculus from their first known appearance, through the formal invention of the method of the calculus in the second half of the seventeenth century, to our own day.
Contributing Partner: UNT Libraries
Comparison of Some Mappings in Topology

Comparison of Some Mappings in Topology

Date: January 1964
Creator: Aslan, Farhad
Description: The main purpose of this paper is the study of transformations in topological space and relationships between special types of transformations.
Contributing Partner: UNT Libraries
Uniqueness Results for the Infinite Unitary, Orthogonal and Associated Groups

Uniqueness Results for the Infinite Unitary, Orthogonal and Associated Groups

Date: May 2008
Creator: Atim, Alexandru Gabriel
Description: Let H be a separable infinite dimensional complex Hilbert space, let U(H) be the Polish topological group of unitary operators on H, let G be a Polish topological group and φ:G→U(H) an algebraic isomorphism. Then φ is a topological isomorphism. The same theorem holds for the projective unitary group, for the group of *-automorphisms of L(H) and for the complex isometry group. If H is a separable real Hilbert space with dim(H)≥3, the theorem is also true for the orthogonal group O(H), for the projective orthogonal group and for the real isometry group. The theorem fails for U(H) if H is finite dimensional complex Hilbert space.
Contributing Partner: UNT Libraries
Contributions to Descriptive Set Theory

Contributions to Descriptive Set Theory

Date: August 2015
Creator: Atmai, Rachid
Description: In this dissertation we study closure properties of pointclasses, scales on sets of reals and the models L[T2n], which are very natural canonical inner models of ZFC. We first characterize projective-like hierarchies by their associated ordinals. This solves a conjecture of Steel and a conjecture of Kechris, Solovay, and Steel. The solution to the first conjecture allows us in particular to reprove a strong partition property result on the ordinal of a Steel pointclass and derive a new boundedness principle which could be useful in the study of the cardinal structure of L(R). We then develop new methods which produce lightface scales on certain sets of reals. The methods are inspired by Jackson’s proof of the Kechris-Martin theorem. We then generalize the Kechris-Martin Theorem to all the Π12n+1 pointclasses using Jackson’s theory of descriptions. This in turns allows us to characterize the sets of reals of a certain initial segment of the models L[T2n]. We then use this characterization and the generalization of Kechris-Martin theorem to show that the L[T2n] are unique. This generalizes previous work of Hjorth. We then characterize the L[T2n] in term of inner models theory, showing that they actually are constructible models over direct limit of ...
Contributing Partner: UNT Libraries
Infinite Planar Graphs

Infinite Planar Graphs

Date: May 2000
Creator: Aurand, Eric William
Description: How many equivalence classes of geodesic rays does a graph contain? How many bounded automorphisms does a planar graph have? Neimayer and Watkins studied these two questions and answered them for a certain class of graphs. Using the concept of excess of a vertex, the class of graphs that Neimayer and Watkins studied are extended to include graphs with positive excess at each vertex. The results of this paper show that there are an uncountable number of geodesic fibers for graphs in this extended class and that for any graph in this extended class the only bounded automorphism is the identity automorphism.
Contributing Partner: UNT Libraries
A Method for Approximating the Distributed Loads of an Airplane by Sets of Point Loads

A Method for Approximating the Distributed Loads of an Airplane by Sets of Point Loads

Date: 1957
Creator: Austin, Charles Wayne
Description: This paper gives the derivation of a method for determining the forces to be applied to these points which will simulate the load distributed over all the airplane.
Contributing Partner: UNT Libraries
Uniformly σ-Finite Disintegrations of Measures

Uniformly σ-Finite Disintegrations of Measures

Date: August 2011
Creator: Backs, Karl
Description: A disintegration of measure is a common tool used in ergodic theory, probability, and descriptive set theory. The primary interest in this paper is in disintegrating σ-finite measures on standard Borel spaces into families of σ-finite measures. In 1984, Dorothy Maharam asked whether every such disintegration is uniformly σ-finite meaning that there exists a countable collection of Borel sets which simultaneously witnesses that every measure in the disintegration is σ-finite. Assuming Gödel’s axiom of constructability I provide answer Maharam's question by constructing a specific disintegration which is not uniformly σ-finite.
Contributing Partner: UNT Libraries
π-regular Rings

π-regular Rings

Date: May 1993
Creator: Badawi, Ayman R.
Description: The dissertation focuses on the structure of π-regular (regular) rings.
Contributing Partner: UNT Libraries
Complemented Subspaces of Bounded Linear Operators

Complemented Subspaces of Bounded Linear Operators

Date: August 2003
Creator: Bahreini Esfahani, Manijeh
Description: For many years mathematicians have been interested in the problem of whether an operator ideal is complemented in the space of all bounded linear operators. In this dissertation the complementation of various classes of operators in the space of all bounded linear operators is considered. This paper begins with a preliminary discussion of linear bounded operators as well as operator ideals. Let L(X, Y ) be a Banach space of all bounded linear operator between Banach spaces X and Y , K(X, Y ) be the space of all compact operators, and W(X, Y ) be the space of all weakly compact operators. We denote space all operator ideals by O.
Contributing Partner: UNT Libraries
Level Curves of the Angle Function of a Positive Definite Symmetric Matrix

Level Curves of the Angle Function of a Positive Definite Symmetric Matrix

Access: Use of this item is restricted to the UNT Community.
Date: December 2009
Creator: Bajracharya, Neeraj
Description: Given a real N by N matrix A, write p(A) for the maximum angle by which A rotates any unit vector. Suppose that A and B are positive definite symmetric (PDS) N by N matrices. Then their Jordan product {A, B} := AB + BA is also symmetric, but not necessarily positive definite. If p(A) + p(B) is obtuse, then there exists a special orthogonal matrix S such that {A, SBS^(-1)} is indefinite. Of course, if A and B commute, then {A, B} is positive definite. Our work grows from the following question: if A and B are commuting positive definite symmetric matrices such that p(A) + p(B) is obtuse, what is the minimal p(S) such that {A, SBS^(-1)} indefinite? In this dissertation we will describe the level curves of the angle function mapping a unit vector x to the angle between x and Ax for a 3 by 3 PDS matrix A, and discuss their interaction with those of a second such matrix.
Contributing Partner: UNT Libraries
Near-Rings

Near-Rings

Date: May 1972
Creator: Baker, Edmond L.
Description: The primary objective of this work is to discuss some of the elementary properties of near-rings as they are related to rings. This study is divided into three subdivisions: (1) Basic Properties and Concepts of Near-Rings; (2) The Ideal Structure of Near-Rings; and (3) Homomorphism and Isomorphism of Near-Rings.
Contributing Partner: UNT Libraries
Completely Simple Semigroups

Completely Simple Semigroups

Date: August 1968
Creator: Barker, Bruce W.
Description: The purpose of this thesis is to explore some of the characteristics of 0-simple semigroups and completely 0-simple semigroups.
Contributing Partner: UNT Libraries
T-Functions

T-Functions

Date: June 1960
Creator: Barlow, John Rice
Description: The main purpose of this paper is to make a detailed study of a certain class T of complex functions. The functions of the class T have a special mapping property and are meromorphic in every region. As an application of this study, certain elementary functions are defined and studied in terms of a special T-function.
Contributing Partner: UNT Libraries
Product and Function Spaces

Product and Function Spaces

Date: August 1971
Creator: Barrett, Lewis Elder
Description: In this paper the Cartesian product topology for an arbitrary family of topological spaces and some of its basic properties are defined. The space is investigated to determine which of the separation properties of the component spaces are invariant.
Contributing Partner: UNT Libraries
Properties of Order Relations and Certain Partly Ordered Systems

Properties of Order Relations and Certain Partly Ordered Systems

Date: June 1961
Creator: Barros, David Nicholas
Description: The purpose of this paper is to present a study of partly ordered sets. It includes a rigorous development of relations based on the notion of a relation as a set, lattices, and theorems concerning the lattice of subgroups of a group.
Contributing Partner: UNT Libraries
Mycielski-Regular Measures

Mycielski-Regular Measures

Date: August 2011
Creator: Bass, Jeremiah Joseph
Description: Let μ be a Radon probability measure on M, the d-dimensional Real Euclidean space (where d is a positive integer), and f a measurable function. Let P be the space of sequences whose coordinates are elements in M. Then, for any point x in M, define a function ƒn on M and P that looks at the first n terms of an element of P and evaluates f at the first of those n terms that minimizes the distance to x in M. The measures for which such sequences converge in measure to f for almost every sequence are called Mycielski-regular. We show that the self-similar measure generated by a finite family of contracting similitudes and which up to a constant is the Hausdorff measure in its dimension on an invariant set C is Mycielski-regular.
Contributing Partner: UNT Libraries
A Set of Axioms for a Topological Space

A Set of Axioms for a Topological Space

Date: August 1960
Creator: Batcha, Joseph Patrick
Description: Axioms for a topological space are generally based on neighborhoods where "neighborhood" is an undefined term. Then, limit points are defined in terms of neighborhoods. However, limit points seem to be the basic concept of a topological space, rather than neighborhoods. For this reason, it will be attempted to state a set of axioms for a topological space, using limit point as the undefined concept, and to delete the idea of neighborhoods from the theory.
Contributing Partner: UNT Libraries
The Development of the Natural Numbers by Means of the Peano Postulates

The Development of the Natural Numbers by Means of the Peano Postulates

Date: 1951
Creator: Baugh, Orvil Lee
Description: This thesis covers the development of the natural numbers by means of the peano postulates.
Contributing Partner: UNT Libraries
On Sets and Functions in a Metric Space

On Sets and Functions in a Metric Space

Date: December 1971
Creator: Beeman, Anne L.
Description: The purpose of this thesis is to study some of the properties of metric spaces. An effort is made to show that many of the properties of a metric space are generalized properties of R, the set of real numbers, or Euclidean n--space, and are specific cases of the properties of a general topological space.
Contributing Partner: UNT Libraries
Lebesgue Linear Measure

Lebesgue Linear Measure

Date: 1940
Creator: Beeman, William Edwin
Description: This paper discusses the concept of a general definition of measure, and shows that the Lebesgue measure satisfies the requirements set forth for the ideal definition.
Contributing Partner: UNT Libraries
Compactness and Equivalent Notions

Compactness and Equivalent Notions

Date: August 1967
Creator: Bell, Wayne Charles
Description: One of the classic theorems concerning the real numbers states that every open cover of a closed and bounded subset of the real line contains a finite subcover. Compactness is an abstraction of that notion, and there are several ideas concerning it which are equivalent and many which are similar. The purpose of this paper is to synthesize the more important of these ideas. This synthesis is accomplished by demonstrating either situations in which two ordinarily different conditions are equivalent or combinations of two or more properties which will guarantee a third.
Contributing Partner: UNT Libraries
Restricting Invariants and Arrangements of Finite Complex Reflection Groups

Restricting Invariants and Arrangements of Finite Complex Reflection Groups

Date: August 2015
Creator: Berardinelli, Angela
Description: Suppose that G is a finite, unitary reflection group acting on a complex vector space V and X is a subspace of V. Define N to be the setwise stabilizer of X in G, Z to be the pointwise stabilizer, and C=N/Z. Then restriction defines a homomorphism from the algebra of G-invariant polynomial functions on V to the algebra of C-invariant functions on X. In my thesis, I extend earlier work by Douglass and Röhrle for Coxeter groups to the case where G is a complex reflection group of type G(r,p,n) in the notation of Shephard and Todd and X is in the lattice of the reflection arrangement of G. The main result characterizes when the restriction mapping is surjective in terms of the exponents of G and C and their reflection arrangements.
Contributing Partner: UNT Libraries
Dimensions in Random Constructions.

Dimensions in Random Constructions.

Date: May 2002
Creator: Berlinkov, Artemi
Description: We consider random fractals generated by random recursive constructions, prove zero-one laws concerning their dimensions and find their packing and Minkowski dimensions. Also we investigate the packing measure in corresponding dimension. For a class of random distribution functions we prove that their packing and Hausdorff dimensions coincide.
Contributing Partner: UNT Libraries
Some Theorems and Product Spaces

Some Theorems and Product Spaces

Date: 1957
Creator: Bethel, Edward Lee
Description: This thesis is a study of some axioms and theorems, and product spaces.
Contributing Partner: UNT Libraries