Mathematics Commons^™

The Projectivity Of The Fundamental Group Of An Affine Line, Moshe Jarden

Turkish Journal of Mathematics

No abstract provided.

On The Asymptotic Behavior Of Heegner Points, Jan Nekovar, Norbert Schappacher

Turkish Journal of Mathematics

We prove that all but finitely many Heegner points on a given modular elliptic curve (or, more generally, on a given quotient of the modular Jacobian variety $J_0(N)$) are of infinite order in the Mordell-Weil group where they naturally live, i.e., over the corresponding ring class field.

Shafarevich-Tate Set For Y^4 = X^4 _ L^2, Takashi Ono

Turkish Journal of Mathematics

No abstract provided.

On Generalized Shioda - Inose Structures, H. Önsi̇per, Si̇nan Sertöz

Turkish Journal of Mathematics

No abstract provided.

Reconstructing Subsets Of Reals, A. J. Radcliffe, A. D. Scott

Department of Mathematics: Faculty Publications

We consider the problem of reconstructing a set of real numbers up to translation from the multiset of its subsets of fixed size, given up to translation. This is impossible in general: for instance almost all subsets of Z contain infinitely many translates of every finite subset of Z. We therefore restrict our attention to subsets of R which are locally finite; those which contain only finitely many translates of any given finite set of size at least 2. We prove that every locally finite subset of R is reconstructible from the multiset of its 3-subsets, given up to …

Algebraic Geometric Codes Over Rings, Judy L. Walker

Department of Mathematics: Faculty Publications

The techniques of algebraic geometry have been widely and successfully applied to the study of linear codes over finite fields since the early 1980’s. Recently, there has been an increased interest in the study of linear codes over finite rings. In this paper, we combine these two approaches to coding theory by introducing the study of algebraic geometric codes over rings. In addition to defining these new codes, we prove several results about their properties.

Computational Geometry Column 35, Joseph O'Rourke

Computer Science: Faculty Publications

The subquadratic algorithm of Kapoor for finding shortest paths on a polyhedron is described.

Locked And Unlocked Polygonal Chains In 3d, Therese Biedl, Erik D. Demaine, Martin L. Demaine, Sylvain Lazard, Anna Lubiw, Joseph O'Rourke, Mark Overmars, Steve Robbins, Ileana Streinu, Godfried Toussaint, Sue Whitesides

Computer Science: Faculty Publications

In this paper, we study movements of simple polygonal chains in 3D. We say that an open, simple polygonal chain can be straightened if it can be continuously reconfigured to a straight sequence of segments in such a manner that both the length of each link and the simplicity of the chain are maintained throughout the movement. The analogous concept for closed chains is convexification: reconfiguration to a planar convex polygon. Chains that cannot be straightened or convexified are called locked. While there are open chains in 3D that are locked, we show that if an open chain has a …

A Quantile‐Based Approach For Relative Efficiency Measurement, Paul M. Griffin, Paul H. Kvam

Department of Math & Statistics Faculty Publications

Two popular approaches for efficiency measurement are a non‐stochastic approach called data envelopment analysis (DEA) and a parametric approach called stochastic frontier analysis (SFA). Both approaches have modeling difficulty, particularly for ranking firm efficiencies. In this paper, a new parametric approach using quantile statistics is developed. The quantile statistic relies less on the stochastic model than SFA methods, and accounts for a firm's relationship to the other firms in the study by acknowledging the firm's influence on the empirical model, and its relationship, in terms of similarity of input levels, to the other firms.

Fisher Information In Weighted Distributions, Satish Iyengar, Paul H. Kvam, Harshinder Singh

Department of Math & Statistics Faculty Publications

Standard inference procedures assume a random sample from a population with density f_μ(x) for estimating the parameter μ. However, there are many applications in which the available data are a biased sample instead. Fisher modeled biased sampling using a weight function w(x) ¸ 0, and constructed a weighted distribution with a density f_μ^w(x) that is proportional to w(x)f_μ(x). In this paper, we assume that f_μ(x) belongs to an exponential family, and study the Fisher information about μ in observations obtained from some commonly arising weighted distributions: (i) the k^th order …

Bayes Estimation Of A Distribution Function Using Ranked Set Samples, Paul H. Kvam, Ram C. Tiwari

Department of Math & Statistics Faculty Publications

Aranked set sample (RSS), if not balanced, is simply a sample of independent order statistics generated from the same underlying distribution F. Kvam and Samaniego (1994) derived maximum likelihood estimates of F for a general RSS. In many applications, including some in the environmental sciences, prior information about F is available to supplement the data-based inference. In such cases, Bayes estimators should be considered for improved estimation. Bayes estimation (using the squared error loss function) of the unknown distribution function F is investigated with such samples. Additionally, the Bayes generalized maximum likelihood estimator (GMLE) is derived. An iterative scheme based …

A Unified Approach To Difference Sets With Gcd(V, N) > 1, James A. Davis, Jonathan Jedwab

Department of Math & Statistics Faculty Publications

The five known families of difference sets whose parameters (v, k, λ; n) satisfy the condition gcd(v,n) > 1 are the McFarland, Spence, Davis-Jedwab, Hadamard and Chen families. We survey recent work which uses recursive techniques to unify these difference set families, placing particular emphasis on examples. This unified approach has also proved useful for studying semi-regular relative difference sets and for constructing new symmetric designs.

Codes, Correlations And Power Control In Ofdm, James A. Davis, Jonathan Jedwab, Kenneth G. Paterson

Department of Math & Statistics Faculty Publications

Practical communications engineering is continually producing problems of interest to the coding theory community. A recent example is the power-control problem in Orthogonal Frequency Division Multiplexing (OFDM). We report recent work which gives a mathematical framework for generating solutions to this notorious problem that are suited to low-cost wireless applications. The key result is a connection between Golay complementary sequences and Reed-Muller codes. The former are almost ideal for OFDM transmissions because they have a very low peak-to-mean envelope power ratio (PMEPR), while the latter have efficient encoding and decoding algorithms and good error correction capability. This result is then …

On The Decomposition Of Order-Separable Posets Of Countable Width Into Chains, Gary Gruenhage, Joe Mashburn

Mathematics Faculty Publications

partially ordered set X has countable width if and only if every collection of pairwise incomparable elements of X is countable. It is order-separable if and only if there is a countable subset D of X such that whenever p, q ∈ X and p < q, there is r ∈ D such that p ≤ r ≤ q. Can every order-separable poset of countable width be written as the union of a countable number of chains? We show that the answer to this question is "no" if there is a 2-entangled subset of IR, and "yes" under the Open Coloring Axiom.

Triple Positive Solutions For Multipoint Conjugate Boundary Value Problems, John M. Davis, Paul W. Eloe, Johnny Henderson

Mathematics Faculty Publications

For the nth order nonlinear differential equation y (n)(t)=f(y(t)), t [0,1], satisfying the multipoint conjugate boundary conditions, y (j)(ai) = 0,1 i k, 0 j n i - 1, 0 =a 1 a 2 a k = 1, and i=1 k n i =n, where f: [0, ) is continuous, growth condtions are imposed on f which yield the existence of at least three solutions that belong to a cone.

International R&D Spillovers: An Application Of Estimation And Inference In Panel Cointegration, Chihwa Kao, Min-Hsien Chiang, Bangtian Chen

Center for Policy Research

In this paper, we apply the asymptotic theory of panel cointegration developed by Kao and Chiang (1997) to Coe and Helpman's (1995) international R&D spillovers regression. The OLS with bias-correction, the fully-modified (FM) and the dynamic OLS (DOLS) estimations produce different predictions about the impact of foreign R&D on total factor productivity (TFP), although all the estimations support the result that domestic R&D is related to TFP.

On The Estimation Of A Linear Time Trend Regression With A One-Way Error Component Model In The Presence Of Serially Correlated Errors, Chihwa Kao, Jamie Emerson

Center for Policy Research

In this paper we study the limiting distributions for ordinary least squares (OLS), fixed effects (FE), first difference (FD), and generalized least squares (GLS) estimators in a linear time trend regression with a one-way error component model in the presence of serially correlated errors. We show that when the error term is I(0), the FE is asymptotically equivalent to the GLS. However, when the error term is I(1) the GLS could be less efficient than the FD or FE estimators, and the FD is the most efficient estimator. However, when the intercept is included in the model and the error …

On The Exactness Of An S-Shaped Bifurcation Curve, Philip Korman, Yi Li

Mathematics and Statistics Faculty Publications

For a class of two-point boundary value problems we prove exactness of an S-shaped bifurcation curve. Our result applies to a problem from combustion theory, which involves nonlinearities like for .

Planar Linkages And Algebraic Sets, Henry C. King

Turkish Journal of Mathematics

No abstract provided.

Compositions Of Darboux And Connectivity Functions, Krzysztof Ciesielski

Faculty & Staff Scholarship

We describe here an example of a Darboux function k from the unit interval I = [0, 1] onto itself such that k is not the composition of any finite collection of connectivity functions from I into I. This answers a question of Ceder [2].

Two Examples Concerning Extendable And Almost Continuous Functions, Krzysztof Ciesielski

Faculty & Staff Scholarship

The main purpose of this paper is to describe two examples. The first is that of an almost continuous, Baire class two, non-extendable function f:[0,1]-->[0,1] with a G_\delta graph. This answers a question of Gibson. The second example is that of a connectivity function F:R²-->R with dense graph such that F^-1(0) is contained in a countable union of straight lines. This easily implies the existence of an extendable function f:R-->R with dense graph such that f^-1(0) is countable.

We also give a sufficient condition for a Darboux …

Mach’S Principle In A Mixed Newton-Einstein Context, Evert Jan Post, Michael Berg

Mathematics, Statistics and Data Science Faculty Works

A closed physical space, in conjunction with scalar versus pseudo scalar distinctions, and an accordingly adapted Gauss theorem, reveal unexpected perspectives on Mach's principle, the mass-energy theorem, and a bonus insight into the nature of the solutions of the Einstein field equations of gravity.

Finite Type Link Homotopy Invariants, Blake Mellor

Mathematics, Statistics and Data Science Faculty Works

Bar-Natan used Chinese characters to show that finite type invariants classify string links up to homotopy. In this paper, I construct the correct spaces of chord diagrams and Chinese characters for links up to homotopy. I use these spaces to show that the only rational finite type invariants of link homotopy are the pairwise linking numbers of the components.

Lack Of Time-Delay Robustness For Stabilization Of A Structural Acoustics Model, George Avalos, Irena Lasiecka, Richard Rebarber

Department of Mathematics: Faculty Publications

In this paper we consider a natural robustness question for a model for structural acoustics. This model, which has been of great interest in recent years, is represented by a wave equation in R^2 coupled to a Kelvin--Voigt beam; the coupling is natural physically, and is represented mathematically by highly unbounded operators. We assume that the observation consists of point evaluation of the beam position, the beam velocity, and the wave velocity. We are interested in the effect of arbitrarily small delays in the feedback loop on a controller that uses these observations. We show that it is not possible …

Geometrical Models For Grain Dynamics, Giovani L. Vasconcelos, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

We study models for the gravity-driven, dissipative motion of a single grain on an inclined rough surface. Imposing some conditions on the momentum loss due to the collisions between the particle and the surface, we arrive at a class of models in which the grain dynamics is described by one-dimensional maps. The dynamics of these maps is studied in detail. We prove the existence of various dynamical phases and show that the presence of these phases is independent of the restitution law (within the class considered).

Utilization Of Printer Resources Within A Computer Graphics Department: A Print Queue Analysis, Prentice Frazier

Theses and Dissertations

This paper examines print queue management for the graphics department of a financial services company. The current network configuration has proven to be sub-optimal. The IT department is currently undergoing testing of possible alternative network configurations. The objective is to improve performance by leveraging existing resources with new technology. In this paper, the effect of consolidating the queue into one primary queue manager is analyzed, along with prioritizing print jobs, and forecasting future printer needs. Analysis was performed using queuing theory concepts along with an analysis of both steady state and transient behavior using simulation modeling.

Canonical Framings For 3 -Manifolds, Rob Kirby, Paul Melvin

Turkish Journal of Mathematics

No abstract provided.

On Symplectic Fillings Of 3-Manifolds, Paola Lisca

Turkish Journal of Mathematics

No abstract provided.

Alternative Polynomial And Holomorphic Dunford-Pettis Properties, Walden Freedman

Turkish Journal of Mathematics

Alternatives to the Polynomial Dunford-Pettis property and the Holomorphic Dunford-Pettis property, called the PDP1 and HDP1 properties, respectively, are introduced. These are shown to be equivalent to the DP1 property, an alternative Dunford-Pettis property previously introduced by the author, thus mirroring the equivalence of the three original properties.

Some Theorems Involving Inequalities On P-Valent Functions, Hüseyi̇n Irmak, Ömer Faruk Çeti̇n

Turkish Journal of Mathematics

In this paper, some theorems involving inequalities on $p$-valent functions (that is $p$-valenty close-to-convex functions, $p$-valently starlike functions, and $p$-valently convex functions) are given. Moreover, some applications in the theorems which are important for geometric function theory are also included. Keywords: Analytic, $p$-valent, $p$-valently colse-to-convex functions, $p$-valently starlike functions, $p$-valently convex functions, open unit disk, and Jack's Lemma.