Physical Sciences and Mathematics Commons^™

Fuzzy Product -Limit Estimators: Soft Computing In The Presence Of Very Small And Highly Censored Data Sets, Kian Lawrence Pokorny

Doctoral Dissertations

When very few data are available and a high proportion of the data is censored, accurate estimates of reliability are problematic. Standard statistical methods require a more complete data set, and with any fewer data, expert knowledge or heuristic methods are required. In the current research a computational system is developed that obtains a survival curve, point estimate, and confidence interval about the point estimate.

The system uses numerical methods to define fuzzy membership functions about each data point that quantify uncertainty due to censoring. The “fuzzy” data are then used to estimate a survival curve, and the mean survival …

On The Inverse Problem For Semivalues Of Cooperative Tu Games, Irinel C. Dragan

Mathematics Technical Papers

In the present paper, we define a basis of [see pdf for notation] relative to a Semivalue, we compute the potentials of the subgames of a given game, to show that the basis is a potential basis, from which we get the Semivalues of the basic vectors. In this way we discover a basis of the null space of a Semivalue and derive, as in the previous work, a solution of the inverse problem, this time for a Semivalue. As the Shapley value was considered in detail in the previous work, we give a complete description for the Banzhaf value. …

Self-Similarity In Network Traffic, Francisco Chinchilla

Honors Theses

It is critical to properly understand the nature of network traffic in order to effectively design models describing network behavior. These models are usually used to simulate network traffic, which in turn are used to construct congestion control techniques, perform capacity planning studies, and/or evaluate the behavior of new protocols. Using the wrong models could lead to potentially serious problems such as delayed packet transmissions or an increase in packet drop rates.

Traditionally, packet arrivals were assumed to follow a Poisson arrival process. Although Poisson processes have several properties that make them easy to work with, they do not accurately …

Smaller Solutions For The Firing Squad, Amber Settle, Janos Simon

Amber Settle

Mathematisation Of The Science Of Motion And The Birth Of Analytical Mechanics : A Historiographical Note, Marco Panza

MPP Published Research

Usually, one speaks of mathematization of a natural or social science to mean that mathematics comes to be a tool of such a science: the language of mathematics is used to formulate its results, and/or some mathematical techniques is employed to obtain these results.

Zero-Cycles And K-Theory On Normal Surfaces., Amalendu Krishna Dr.

Doctoral Theses

The main theme of this thesis is to study the theory of algebraic cycles on singular varieties over a field. This has been studied before extensively by Collins, Barbieri-Viale, Levine, Srinivas among several others. Our interest in this thesis is to address some well known problems in the theory of zero-cycles over nominal varieties. The use of K- theoretic techniques in our proofs illustrate the interplay between the study of algebraic cycles and algebraic K-theory.For a quasi-projective surface X over a field k, we define FA,(X) to be the subgroup of the Grothendieck group Ko(X) of vector bundies generated by …

The Stable Manifold Theorem For Stochastic Differential Equations (Mathematics Colloquium, University Of North Carolina, Charlotte), Salah-Eldin A. Mohammed

Miscellaneous (presentations, translations, interviews, etc)

No abstract provided.

Boundary Layers Associated With Incompressible Navier-Stokes Equations: The Noncharacteristic Boundary Case, R. Temam, X. Wang

Mathematics and Statistics Faculty Research & Creative Works

The goal of this article is to study the boundary layer of wall bounded flows in a channel at small viscosity when the boundaries are uniformly non-characteristic, i.e., there is injection and/or suction everywhere at the boundary. Following earlier work on the boundary layer for linearized Navier-Stokes equations in the case where the boundaries are characteristic (non-slip at the boundary and non-permeable), we consider here the case where the boundary is permeable and thus non-characteristic. the form of the boundary layer and convergence results are derived in two cases: linearized equation and full nonlinear equations. We prove that there exists …

Renewal Systems, Sharp-Eyed Snakes, And Shifts Of Finite Type, Aimee S. A. Johnson, K. M. Madden

Mathematics & Statistics Faculty Works

Johnson and Madden look at collections of bi-infinite strings of symbols that occur in several different areas of mathematics and ask whether these collections are the same in some sense. A dynamical systems property called entropy can be used to show that the shifts of finite type are not all conjugate to uniquely decipherable renewal systems.

Mixed Partial Derivatives And Fubini's Theorem, Asuman Güven Aksoy, Mario Martelli

CMC Faculty Publications and Research

A most fascinating aspect of calculus is its power to surprise even an experienced mathemat ician. Just when it appears that all ideas, results and connections have been discovered and thorough ly analyzed, the horizon suddenly broadens and somebody cries the familiar "eureka". The reason could be either a new result, a simpler way to prove an existing theorem, or a previously missed connection between different ideas. This potential for enrichment is second to none, and it reaffirms the unparalleled educational value of this area of mathematics.

Transition To Chaos In Continuous-Time Random Dynamical Systems, Zonghua Liu, Ying-Cheng Lai, Lora Billings, Ira B. Schwartz

Department of Mathematics Facuty Scholarship and Creative Works

We consider situations where, in a continuous-time dynamical system, a nonchaotic attractor coexists with a nonattracting chaotic saddle, as in a periodic window. Under the influence of noise, chaos can arise. We investigate the fundamental dynamical mechanism responsible for the transition and obtain a general scaling law for the largest Lyapunov exponent. A striking finding is that the topology of the flow is fundamentally disturbed after the onset of noisy chaos, and we point out that such a disturbance is due to changes in the number of unstable eigendirections along a continuous trajectory under the influence of noise.

An Adaptive Analysis Of Covariance Using Tree-Structured Regression, Gary L. Gadbury, H. K. Iyer, H. T. Schreuder

Mathematics and Statistics Faculty Research & Creative Works

In this article, we propose an adaptive procedure for testing for the effect of a factor of interest in the presence of one or more confounding variables in observational studies. It is especially relevant for applications where the factor of interest has a suspected causal relationship with a response. This procedure is not tied to linear modeling or normal distribution theory, and it offers a valuable alternative to traditional methods. It is suitable for applications where a factor of interest is categorical, and the response is continuous. Confounding variables may be continuous or categorical. The method is comprised of two …

L-Arginine Uptake And Metabolism Following In Vivo Silica Exposure In Rat Lungs, Leif D. Nelin, Gary S. Krenz, Louis G. Chicoine, Christopher A. Dawson, Ralph M. Schapira

Mathematics, Statistics and Computer Science Faculty Research and Publications

Pulmonary inflammation increases nitric oxide (NO) production via inducible nitric oxide synthase (iNOS). This study was performed to determine some of the factors that affect the availability of the NOS substrate, L-arginine (L-arg), in the intact lung subjected to silica-induced inflammation. Nitrate production, as an index of NO production, was significantly greater in silica-exposed lungs (53.5 ± 12.1 nmol/90 min) compared with controls (22.5 ±5.1 nmol/90 min, P < 0.05). This was accompanied by greater (P< 0.0001) 90-min [³H]L-arg uptake (62 ± 3% control, 82 ± 1% silica), a significantly (P < 0.005) increased permeability-surface area product for L-arg(0.28 ± 0.05 ml/min control, 0.63 ± 0.07 ml/min silica), and asignificantly (P < 0.001) increased urea production (1.16 ± 0.08µmol/90 min control, 1.77 ± 0.06 µmol/90 min silica). There was no difference in eNOS protein between groups and eNOS mRNA was not detectable in either group, whereas silica exposure resulted in the appearance of both iNOS protein and mRNA. Silica exposure increased CAT-1 and CAT-2 mRNA ~ 8-fold compared with controls. We conclude that the increase in NO production in silica-exposed lungs was associated with increased L-arg uptake from the vasculature, presumably resulting from increased CAT-1 and CAT-2, and by increased L-arg metabolism via arginase.

Enumerating Foldings And Unfoldings Between Polygons And Polytopes, Erik D. Demaine, Martin L. Demaine, Anna Lubiw, Joseph O'Rourke

Computer Science: Faculty Publications

We pose and answer several questions concerning the number of ways to fold a polygon to a polytope, and how many polytopes can be obtained from one polygon; and the analogous questions for unfolding polytopes to polygons. Our answers are, roughly: exponentially many, or nondenumerably infinite.

Fortran Program Hh1, Donald Greenspan

Mathematics Technical Papers

No abstract provided.

Parallel Implementation Of The Bi-Cgstab Method With Block Red–Black Gauss–Seidel Preconditioner Applied To The Hermite Collocation Discretization Of Partial Differential Equations, Stephen Brill, George Pinder

Stephen H. Brill

We describe herein the parallel implementation of the Bi-CGSTAB method with a block red–black Gauss–Seidel (RBGS) preconditioner applied to the systems of linear algebraic equations that arise from the Hermite collocation discretization of partial differential equations in two spatial dimensions. The method is implemented on the Cray T3E, a parallel processing supercomputer. Speedup results are discussed.

Essay On Trade In Goods And Factor Movements Under Increasing Returns To Scale., Brati Sankar Chakraborty Dr.

Doctoral Theses

The central issues that have engaged trade theorists from its inception can broadly be classified under three leads. First, to identify, what countries trade with each other, or what has come to be known as the question of pattern of trade. Second, the consequent gains that trade allows for. And the third, which is an immediate appendage to the second is to identify the redistribution of income due to trade.The first and the third, as is immediately evident, are issues in positive trade theory. The second is a normative issue, which evidently brings in questions of welfare change of the …

Differential Equation Of Appell Polynomials Via The Factorization Method, Matthew He, Paolo E. Ricci

Mathematics Faculty Articles

Let {P_n(x)}^∞_n=0 be a sequence of polynomials of degree n. We define two sequences of differential operators Φ_n and Ψ_n satisfying the following properties:

By constructing these two operators for Appell polynomials, we determine their differential equations via the factorization method introduced by Infeld and Hull (Rev. Mod. Phys. 23 (1951) 21). The differential equations for both Bernoulli and Euler polynomials are given as special cases of the Appell polynomials.

A Meshless Gradient Recovery Method Part I: Superconvergence Property, Zhiming Zhang, Ahmed Naga

Mathematics Research Reports

A new gradient recovery method is introduced and analyzed. It is proved that the method is superconvergent for translation invariant finite element spaces of any order. The method maintains the simplicity, efficiency, and superconvergence properties of the Zienkiewicz-Zhu patch recovery method. In addition, under uniform triangular meshes, the method is superconvergent for the Chevron pattern, and ultraconvergence at element edge centers for the regular pattern.

Orthogonal Arrays Of Strength Three From Regular 3-Wise Balanced Designs, Charles J. Colbourn, D. L. Kreher, John P. Mcsorley, D. R. Stinson

Articles and Preprints

The construction given in Kreher, J Combin Des 4 (1996) 67 is extended to obtain new infinite families of orthogonal arrays of strength 3. Regular 3-wise balanced designs play a central role in this construction.

A New Theory Of Premixed Flames In Near-Stoichiometric Mixtures, Eliana S. Antoniou

Dissertations

In this dissertation, a new model of premixed flames in near-stoichiometric mixtures is derived. Unlike most previous theories, which are valid only for very lean or very rich, i.e. off-stoichiometric conditions, our model remains valid over the entire spectrum of mixture compositions, from lean to rich, including the near-stoichiometric regime. Since fuel-mixture composition is known to have a significant effect on flame behavior, such a model is expected to contribute new insights into classical problems in premixed combustion.

In the first part of this dissertation, we describe the derivation of a model for premixed flames in two-reactant mixtures in a …

Essays On Cooperative Behaviour And Collective Action., Anindya Bhattacharya Dr.

Doctoral Theses

This dissertation explores some issues concerning the behaviour of coalitions of individuals in a game theoretic set-up and also studies one aspect of a society facing collective action of the masses. The common feature of the issues explored in the dissertation is that it investigates the properties of stable social states. Chapter 2 introduces a notion of a social state that is unlikely to be displaced by any coalition of agents endowed with a certain notion of rationality and a certain degree of farsightedness and explores the properties of such states. Chapter 3 is also concerned with coalitionally stable social …

On Graphs With Equal Algebraic And Vertex Connectivity, Stephen J. Kirkland, Jason J. Molitierno, Michael Neumann, Bryan L. Shader

Mathematics Faculty Publications

No abstract provided.

Sheaf Cohomology Of Conscious Entity, Goro Kato

Mathematics

Awareness of a conscious entity can exist without elements; therefore, the general notion of an object of a category is employed. One of the characterization of understanding is: for a given local infonnation (awareness) there exists a global information whose restriction is the given information. For such mental activities, category and sheaf theories are employed to formulate consciousness. We will show that the cohomology (more general precohomology) object, a subquotient object, better represents the essence of a conscious entity than an object itself. We will also give a definition of an observation to fonnulate the collapse of the wave and …

Category Theory And Consciousness, Goro Kato, Daniele C. Struppa

Mathematics

No abstract provided.

Orbifold Homeomorphism And Diffeomorphism Groups, Joseph E. Borzellino, Victor Brunsden

Mathematics

In this paper we outline results on orbifold diffeomorphism groups that were presented at the International Conference on Infinite Dimensional Lie Groups in Geometry and Representation Theory at Howard University, Washington DC on August 17-21, 2000. Specifically, we define the notion of reduced and unreduced orbifold diffeomorphism groups. For the reduced orbifold diffeomorphism group we state and sketch the proof of the following recognition result: Let O1 and O2 be two compact, locally smooth orbifolds. Fix r ≥ 0. Suppose that Φ : Diffr (O1) → Diffr (O2) is a group isomorphism. Then Φ is induced by redred a (topological) …

Levy-Like Continuity Theorems For Convergence In Distribution, Theodore P. Hill, Ulrich Krengel

Research Scholars in Residence

Levy’s classical continuity theorem states that if the pointwise limit of a sequence of characteristic functions exists, then the limit function itself is a characteristic function if and only if the limit function satisfies a single universal limit condition (in his case, the limit at zero is one), in which case the underlying measures converge weakly to the probability measure represented by the limit function. It is the purpose of this article to give a number of direct analogs of L´evy’s theorem for other probability-representing functions including moment sequences, maximal moment sequences, mean-residual-life functions, Hardy-Littlewood maximal functions, and failure-rate functions. …

Hilbert Spaces Induced By Toeplitz Covariance Kernels, Mihaela Teodora Matache, Valentin Matache

Faculty Books and Monographs

This is a book chapter that appeared in Stochastic Theory and Control by Bozenna Pasik-Duncan (ed.).

This volume contains almost all of the papers that were presented at the Workshop on Stochastic Theory and Control that was held at the Univ- sity of Kansas, 18–20 October 2001. This three-day event gathered a group of leading scholars in the ?eld of stochastic theory and control to discuss leading-edge topics of stochastic control, which include risk sensitive control, adaptive control, mathematics of ?nance, estimation, identi?cation, optimal control, nonlinear ?ltering, stochastic di?erential equations, stochastic p- tial di?erential equations, and stochastic theory and its …

Outlining Proofs In Calculus, Andrew Wohlgemuth

Mathematics and Statistics Faculty Scholarship

Consider a point p and a line l in some plane, with p not on l: How many lines are there in the plane that pass through point p and that are parallel to line l? It seems clear, by what we mean by “point”, “line”, and “plane”, that there is just one such line. This assertion is logically equivalent to Euclid's 5th, or parallel, postulate (in the context of his other postulates).

In fact, this was seen as so obvious by everyone, mathematicians included, that for two thousand years mathematicians attempted to prove it. After all, if it was …

Embedding Problems And Finite Quotients, Ted Chinburg, Darren B. Glass

Math Faculty Publications

We give a condition on a family of solutions of quotients of an embedding problem which implies the embedding problem has a solution. This shows, in particular, that to solve an embedding problem associated to the maximal extension of a number field unramified outside a fixed finite set of places, it suffices to find a solution for each finite quotient of the embedding problem. This statement is not true in general over global function fields, but one can prove variants of it in this case in which extra conditions on the embedding problems or on the ramification of solutions are …