UNT Libraries - 394 Matching Results
Results as a List of Thumbnails and Descriptive Information Results as a Grid of Images Print This Result Page Keep up to Date with an RSS feed of results matching your query.
Description: In this dissertation, we describe the automorphism groups for the strong Bruhat orders A_n-1, B_n, and D_n. In particular, the automorphism group of A_n-1 for n ≥ 3 is isomorphic to the dihedral group of order eight, D_4; the automorphism group of B_n for n ≥ 3 is isomorphic to C_2 x C_2 where C_2 is the cyclic group of order two; the automorphism group of D_n for n > 5 and n even is isomorphic to C_2 x C_2 x C_2; and the automorphism group of D_n for n ≥ 5 and n odd is isomorphic to the dihedral group D_4.
Date: August 1986
Creator: Sutherland, David C. (David Craig)
Description: In this paper several equivalences of the axiom of choice are examined. In particular, the axiom of choice, Zorn's lemma, Tukey's lemma, the Hausdorff maximal principle, and the well-ordering theorem are shown to be equivalent. Cardinal and ordinal number theory is also studied. The Schroder-Bernstein theorem is proven and used in establishing order results for cardinal numbers. It is also demonstrated that the first uncountable ordinal space is unique up to order isomorphism. We conclude by encountering several applications of the axiom of choice. In particular, we show that every vector space must have a Hamel basis and that any two Hamel bases for the same space must have the same cardinality. We establish that the Tychonoff product theorem implies the axiom of choice and see the use of the axiom of choice in the proof of the Hahn- Banach theorem.
Date: August 1983
Creator: Race, Denise T. (Denise Tatsch)
Description: The purpose of this paper is to develop some of the more basic Fourier transforms which are the outgrowth of the Fourier theorem. Although often approached from the stand-point of the series, this paper will approach the theorem from the standpoint of the integral.
Date: January 1962
Creator: Cumbie, James Randolph
Description: Borel determinacy states that if G(T;X) is a game and X is Borel, then G(T;X) is determined. Proved by Martin in 1975, Borel determinacy is a theorem of ZFC set theory, and is, in fact, the best determinacy result in ZFC. However, the proof uses sets of high set theoretic type (N1 many power sets of ω). Friedman proved in 1971 that these sets are necessary by showing that the Axiom of Replacement is necessary for any proof of Borel Determinacy. To prove this, Friedman produces a model of ZC and a Borel set of Turing degrees that neither contains nor omits a cone; so by another theorem of Martin, Borel Determinacy is not a theorem of ZC. This paper contains three main sections: Martin's proof of Borel Determinacy; a simpler example of Friedman's result, namely, (in ZFC) a coanalytic set of Turing degrees that neither contains nor omits a cone; and finally, the Friedman result.
Date: December 2001
Creator: Bryant, Ross
Description: In leading up to the proof, methods for constructing fields and finitely additive set functions are introduced with an application involving the Tagaki function given as an example. Also, non-absolutely continuous set functions are constructed using Banach limits and maximal filters.
Date: May 1989
Creator: Gurney, David R. (David Robert)
Description: This problem has been selected from the mathematical theory of elasticity. We consider a rectangular plate of thickness h, length a, and width b. The plate is subjected to compressive forces. These forces act in the neutral plane and give the plate a tendency to buckle. However, this problem differs from other plate problems in that it is assumed that there are two intermediate supports located on the edges of the plate parallel to the compressive forces.
Creator: Dean, Thomas S.
Description: This thesis covers the Cantor Ternary Set and generalizations of the Cantor Set, and gives a complete existential theory for three set properties: denumerability, exhaustibility, and zero measure.
Creator: Hembree, Gwendolyn
Description: Let G be a Lie group acting on a homogeneous space G/K. The center of the universal enveloping algebra of the Lie algebra of G maps homomorphically into the center of the algebra of differential operators on G/K invariant under the action of G. In the case that G is a Jacobi Lie group of rank 2, we prove that this homomorphism is surjective and hence that the center of the invariant differential operator algebra is the image of the center of the universal enveloping algebra. This is an extension of work of Bringmann, Conley, and Richter in the rank 1case.
Date: August 2013
Creator: Dahal, Rabin
Description: In this thesis, we shall attempt to present a study of certain properties of real functions related to the set property exhaustible.
Creator: Bradford, James C.
Description: We give conditions which, given two Bernoulli trial measures, determine whether there exists a homeomorphism of Cantor space which sends one measure to the other, answering a question of Oxtoby. We then provide examples, relating these results to the notions of good and refinable measures on Cantor space.
Date: August 2006
Creator: Yingst, Andrew Q.
Description: In this thesis, some characterizations of continua of finite degree are given. It turns out that being of finite degree (by formal definition) can be described by saying there exists an equivalent metric in which Hausdorff linear measure of the continuum is finite. I discuss this result in detail.
Date: August 2006
Creator: Irwin, Shana
Description: We give several characterizations of partition lattices and projective geometries. Most of these characterizations use characteristic polynomials. A geometry is non—splitting if it cannot be expressed as the union of two of its proper flats. A geometry G is upper homogeneous if for all k, k = 1, 2, ... , r(G), and for every pair x, y of flats of rank k, the contraction G/x is isomorphic to the contraction G/y. Given a signed graph, we define a corresponding signed—graphic geometry. We give a characterization of supersolvable signed graphs. Finally, we give the following characterization of non—splitting supersolvable signed-graphic geometries : If a non-splitting supersolvable ternary geometry does not contain the Reid geometry as a subgeometry, then it is signed—graphic.
Date: August 1992
Creator: Yoon, Young-jin
Description: This paper is a study of the relation between smoothness of the norm on a normed linear space and the property that every Chebyshev subset is convex. Every normed linear space of finite dimension, having a smooth norm, has the property that every Chebyshev subset is convex. In the second chapter two properties of the norm, uniform Gateaux differentiability and uniform Frechet differentiability where the latter implies the former, are given and are shown to be equivalent to smoothness of the norm in spaces of finite dimension. In the third chapter it is shown that every reflexive normed linear space having a uniformly Gateaux differentiable norm has the property that every weakly closed Chebyshev subset, with non-empty weak interior that is norm-wise dense in the subset, is convex.
Date: December 1974
Creator: Svrcek, Frank J.
Description: The purpose of this paper is the investigation and classification of regular planar graphs. The motive behind this investigation was a desire to better understand those properties which allow a graph to be represented in the plane in such a manner that no two edges cross except perhaps at vertices.
Date: December 1972
Creator: McCalla, Linda F.
Description: Assuming the axiom of determinacy, we give a new proof of the strong partition relation on ω1. Further, we present a streamlined proof that J<λ+(a) (the ideal of sets which force cof Π α < λ) is generated from J<λ+(a) by adding a singleton. Combining these results with a polarized partition relation on ω1
Date: May 2001
Creator: May, Russell J.
Description: The purpose of this paper is to examine properties of convex sets in linear topological spaces with special emphasis on compact convex sets.
Date: May 1964
Creator: Read, David R.
Description: In this thesis I look at the theory of compact operators in a general Hilbert space, as well as the inverse of the Hamiltonian operator in the specific case of L2[a,b]. I show that this inverse is a compact, positive, and bounded linear operator. Also the eigenfunctions of this operator form a basis for the space of continuous functions as a subspace of L2[a,b]. A numerical method is proposed to solve for these eigenfunctions when the Hamiltonian is considered as an operator on Rn. The paper finishes with a discussion of examples of Schrödinger equations and the solutions.
Date: December 2006
Creator: Kazemi, Parimah
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.
Date: August 1967
Creator: Bell, Wayne Charles
Description: We study the development of nonlinear conjugate gradient methods, Fletcher Reeves (FR) and Polak Ribiere (PR). FR extends the linear conjugate gradient method to nonlinear functions by incorporating two changes, for the step length αk a line search is performed and replacing the residual, rk (rk=b-Axk) by the gradient of the nonlinear objective function. The PR method is equivalent to FR method for exact line searches and when the underlying quadratic function is strongly convex. The PR method is basically a variant of FR and primarily differs from it in the choice of the parameter βk. On applying the nonlinear Rosenbrock function to the MATLAB code for the FR and the PR algorithms we observe that the performance of PR method (k=29) is far better than the FR method (k=42). But, we observe that when the MATLAB codes are applied to general nonlinear functions, specifically functions whose minimum is a large negative number not close to zero and the iterates too are large values far off from zero the PR algorithm does not perform well. This problem with the PR method persists even if we run the PR algorithm for more iterations or with an initial guess closer to the actual minimum. To improve the PR algorithm we suggest finding a better weighing parameter βk, using better line search method and/or using specific line search for certain functions and identifying specific restart criteria based on the function to be optimized.
Date: August 2013
Creator: Pathak, Subrat
Filter: World RegionsThis dialog allows you to filter your current search. Each of the World Regions listed note their name and the number of records that will be limited down to if you choose that option.
Filter: CountriesThis dialog allows you to filter your current search. Each of the Countries listed note their name and the number of records that will be limited down to if you choose that option.
Filter: U.S. StatesThis dialog allows you to filter your current search. Each of the U.S. States listed note their name and the number of records that will be limited down to if you choose that option.
Filter: CountiesThis dialog allows you to filter your current search. Each of the Counties listed note their name and the number of records that will be limited down to if you choose that option.
Filter: DecadesThis dialog allows you to filter your current search. Each of the Decades listed note their name and the number of records that will be limited down to if you choose that option. The list can be sorted by name or the count.
Filter: YearsThis dialog allows you to filter your current search. Each of the Years listed note their name and the number of records that will be limited down to if you choose that option. The list can be sorted by name or the count.
Having trouble finding an option within the list of Years? Start typing and we'll update the list to show only those items that match your needs.
1940 5 5 1941 3 3 1942 1 1 1944 1 1 1945 2 2 1947 2 2 1948 5 5 1949 4 4 1950 7 7 1951 6 6 1952 2 2 1953 3 3 1954 3 3 1955 2 2 1956 3 3 1957 11 11 1958 6 6 1959 5 5 1960 9 9 1961 10 10 1962 5 5 1963 3 3 1964 10 10 1965 13 13 1966 18 18 1967 11 11 1968 17 17 1969 6 6 1970 9 9 1971 14 14 1972 15 15 1973 9 9 1974 8 8 1975 6 6 1976 2 2 1977 4 4 1978 1 1 1980 2 2 1982 3 3 1983 4 4 1985 2 2 1986 3 3 1987 3 3 1988 6 6 1989 4 4 1990 2 2 1991 2 2 1992 4 4 1993 7 7 1994 6 6 1995 7 7 1996 2 2 1997 3 3 1998 7 7 1999 4 4 2000 3 3 2001 6 6 2002 3 3 2003 3 3 2004 6 6 2005 2 2 2006 8 8 2007 2 2 2008 4 4 2009 5 5 2010 2 2 2011 5 5 2012 8 8 2013 7 7 2014 3 3 2015 5 5 2016 8 8 2017 2 2