Physical Sciences and Mathematics Commons^™

Teaching Random Assignment: Do You Believe It Works?, Shlomo S. Sawilowsky

Theoretical and Behavioral Foundations of Education Faculty Publications

Textbook authors admonish students to check on the comparability of two randomly assigned groups by conducting statistical tests on pretest means to determine if randomization worked. A Monte Carlo study was conducted on a sample of n = 2 per group, where each participant’s personality profile was represented by 7,500 randomly selected and assigned scores. Independent samples t tests were conducted and the results demonstrated that random assignment was successful in equating the two groups on 7,467 variables. The students’ focus is redirected from the ability of random assignment to create comparable groups to the testing of the claims of …

Fréchet Subdifferential Calculus And Optimality Conditions In Nondifferentiable Programming, Boris S. Mordukhovich, Nguyen Mau Nam, N. D. Yen

Mathematics Research Reports

We develop various (exact) calculus rules for Frechet lower and upper subgradients of extended-realvalued functions in general Banach spaces. Then we apply this calculus to derive new necessary optimality conditions for some remarkable classes of problems in constrained optimization including minimization problems for difference-type functions under geometric and operator constraints as well as subdifferential optimality conditions for the so-called weak sharp minima.

Determination Of The Cyanide Metabolite 2-Aminothiazoline-4-Carboxylic Acid In Urine And Plasma By Gas Chromatography–Mass Spectrometry, Brian A. Logue, Nicholas P. Kirschten, Ilona Petrikovics, Matthew A, Moser, Gary A. Rockwood, Steven I. Baskin

Chemistry and Biochemistry Faculty Publications

The cyanide metabolite 2-aminothiazoline-4-carboxylic acid (ATCA) is a promising biomarker for cyanide exposure because of its stability and the limitations of direct determination of cyanide and more abundant cyanide metabolites. A simple, sensitive, and specific method based on derivatization and subsequent gas chromatography–mass spectrometry (GC–MS) analysis was developed for the identification and quantification of ATCA in synthetic urine and swine plasma. The urine and plasma samples were spiked with an internal standard (ATCA-d2), diluted, and acidified. The resulting solution was subjected to solid phase extraction on a mixed-mode cation exchange column. After elution and evaporation of the solvent, a silylating …

Bayesian Wavelet Estimation Of Long Memory Parameter, Leming Qu

Mathematics Faculty Publications and Presentations

A Bayesian wavelet estimation method for estimating parameters of a stationary I(d) process is represented as an useful alternative to the existing frequentist wavelet estimation methods. The effectiveness of the proposed method is demonstrated through Monte Carlo simulations. The sampling from the posterior distribution is through the Markov Chain Monte Carlo (MCMC) easily implemented in the WinBUGS software package.

An Entry To A Chiral Dihydropyrazole Scaffold:  Enantioselective [3 + 2] Cycloaddition Of Nitrile Imines, Mukund P. Sibi, Levi M. Stanley, Craig P. Jasperse

Levi M. Stanley

We have developed a versatile strategy to access dihydropyrazoles in highly enantioenriched form. Dipolar cycloaddition of electron-deficient acceptors and in situ-generated nitrile imines proceeds with high regio- and enantioselectivity using 10 mol % chiral Lewis acid catalyst. A variety of dihydropyrazoles that incorporate functionality for further manipulation have been prepared.

Hinge-Like Motions In Rna Kink-Turns: The Role Of The Second A-Minor Motif And Nominally Unpaired Bases, Neocles B. Leontis, Filip Rázga, Jaroslav Koča, Jiří Šponer

Chemistry Faculty Publications

Kink-turn (K-turn) motifs are asymmetric internal loops found at conserved positions in diverse RNAs, with sharp bends in phosphodiester backbones producing V-shaped structures. Explicit-solvent molecular dynamics simulations were carried out for three K-turns from 23S rRNA, i. e., Kt-38 located at the base of the A-site. nger, Kt-42 located at the base of the L7/L12 stalk, and Kt-58 located in domain III, and for the K-turn of human U4 snRNA. The simulations reveal hinge-like K-turn motions on the nanosecond timescale. The first conserved A-minor interaction between the K-turn stems is entirely stable in all simulations. The angle between the helical …

Σary, Minnesota State University Moorhead, Mathematics Department

Math Department Newsletters

No abstract provided.

The Convergence Of Difference Boxes, Antonio Behn, Christopher Kribs-Zaleta, Vadim Ponomarenko

Mathematics Faculty Research

We consider an elementary mathematical puzzle known as a "difference box" in terms of a discrete map from R4 to R4 or, canonically, from a subset of the first quadrant of R2 into itself. We find the map's unique canonical fixed point and answer the general question of how many iterations a given "difference box" takes to reach zero.

The Probe, Issue 238 – May/June 2005

The Probe: Newsletter of the National Animal Damage Control Association

Dusting Off the CLOD -- Are Berentsen, Research Associate, Utah State University, Jack H. Berryman Institute
A Last Resort for Bear and Lion Problems -- By Dexter K. Oliver, Duncan, Arizona
Book Review: “Innovative Skunk Control” by Rob Erickson (DeKalb, Ill: R.J.E. Publications, 2005.) paperback pp. 1-79. $15.95
BEIJING - China imported a U.S.-made scream machine to scare away the birds at Beijing airport -- except they didn’t recognize the noises and refused to budge.

When Scoundrels Rule: Review Of The Last Refuge: Patriotism, Politics, And The Environment In An Age Of Terror, By David W. Orr, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Book Review of The Last Refuge: Patriotism, Politics, and the Environment in an Age of Terror. David W. Orr. Island Press, Washington, DC, 2004.

Synthesis, Structural Studies And Desilylation Reactions Of Some N-2-(Trimethylsilyl)Ethyl-N-Nitrosocarbamates, Arpitha Thakkalapally, Vladimir Benin

Chemistry Faculty Publications

The present report describes the preparation and characterization of several N-2-(trimethylsilyl)ethyl-N-nitrosocarbamates, designed as precursors to thermally unstable secondary N-nitrosocarbamate anions via fluoride-assisted cleavage. X-ray structural studies demonstrate that the core N-nitrosocarbamate moiety has a nearly planar geometry, with an s-E orientation at the N–N bond. DFT calculations (B3LYP/6-31+G(d)) reproduce accurately the structural features of the title compounds and detailed conformational analysis at the same level of theory addresses the long-standing issue of preferred geometries for three classes of related structures: N-nitrosocarbamates, N-nitrosoureas and N-nitrosoamides. Desilylation studies demonstrate that both the …

Aggregated Path Authentication For Efficient Bgp Security, Meiyuan Zhao, Sean W. Smith, David M. Nicol

Computer Science Technical Reports

The border gateway protocol (BGP) controls inter-domain routing in the Internet. BGP is vulnerable to many attacks, since routers rely on hearsay information from neighbors. Secure BGP (S-BGP) uses DSA to provide route authentication and mitigate many of these risks. However, many performance and deployment issues prevent S-BGP's real-world deployment. Previous work has explored improving S-BGP processing latencies, but space problems, such as increased message size and memory cost, remain the major obstacles. In this paper, we combine two efficient cryptographic techniques---signature amortization and aggregate signatures---to design new aggregated path authentication schemes. We propose six constructions for aggregated path authentication …

An O(N^{5/2} Log N) Algorithm For The Rectilinear Minimum Link-Distance Problem In Three Dimensions (Extended Abstract), Robert Scot Drysdale, Clifford Stein, David P. Wagner

Computer Science Technical Reports

In this paper we consider the Rectilinear Minimum Link-Distance Problem in Three Dimensions. The problem is well studied in two dimensions, but is relatively unexplored in higher dimensions. We solve the problem in O(B n log n) time, where n is the number of corners among all obstacles, and B is the size of a BSP decomposition of the space containing the obstacles. It has been shown that in the worst case B = Theta(n^{3/2}), giving us an overall worst case time of O(n^{5/2} log n). Previously known algorithms have had worst-case running times of Omega(n^3).

Preparation, Structural Characterization, And Dynamic Properties Investigation Of Permalloy Antidot Arrays, Scott Whittenburg, Charles J. O'Connor

Chemistry Faculty Publications

Regular nanosized structures are considered to be promising materials for magnetic information storage media with high density of information. Recently attention was paid to static and dynamic magnetic properties arising from dimensional confinement in such nanostructures. Here we present an investigation of permalloy antidot arrays of different thicknesses. Thin permalloy films of thickness ranging from 10 to 500 nm were deposited on anoporous Al2O3 membranes with a pore size of 100 nm. It was found that additional ferromagnetic resonance peaks appear for film thicknesses below 100 nm, while films with larger thicknesses show resonance properties similar to continuous films. A …

Wavelet Factorization Via A Homogenization Analogy For Solutions Of Linear Systems, Andrea Van Sickle

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A system of linear equations can be solved using a factorization method that produces a wavelet structure and is akin to a homogenization process used in determining the solution of differential equations. The method is dependant on the particular structure of Hadamard matrices and their implementation in a similarity transform. This paper details the development of such a method for systems of size 2n x 2n, including establishing the theoretical underpinnings necessary to define an orthogonal transform. Also, we present the development of an algorithm to implement the method for a simple 2 x 2 system, which will then be …

Simulation Study Of Estimation And Inference In Factor Analysis: Normal And Non-Normal Noise Distributions, Ping Zhang

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Objective: To study the estimation and inference m factor analyses when the data have normal or non-normal noise distributions.

Methods: Population data were created in package R with a specified number of factors, factor structure and observable variables with known loadings. Then, repeated simple random samples (SRS's) were taken from the population, independently. The maximum likelihood method with varimax rotation was used to perform factor analysis and inference on each sampled dataset. Factor loadings were estimated to determine if the estimation of the loadings was (approximately) unbiased and/or efficient for each specified population and chi-square x2-statistics were obtained to test …

Special Classification Models For Lichens In The Pacific Northwest, Janeen Ardito

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A common problem in ecological studies is that of determining where to look for rare species. This paper shows how statistical models, such as classification trees, may be used to assist in the design of probability-based surveys for rare species using information on more abundant species that are associated with the rare species. This model assisted approach to survey design involves first building models for the more abundant species. The models are then used to determine stratifications for the rare species that are associated with the more abundant species. The goal of this approach is to increase the number of …

Aldol Reactions: E-Enolates And Anti-Selectivity, Matthew Grant Anderson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A common structural motif in complicated natural product molecules is an alkyl group at an alpha position to a carbonyl and an alcohol at the beta position anti to each other. This arrangement occurs in bioactive molecules that are important for medical research such as spongistatin A at the C15-C16 position and in (-)-baconipyrone C at C12-C13. Bioactive molecules such as these generally occur in such a low concentration in the organism in which they originate that deriving them from the natural source for research is not practical so efficient syntheses are sought. Reactions that produce 1,2 syn aldol products …

New Views Of The U.S. Continental Margins, James V. Gardner, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

No abstract provided.

The Chromospheric Activity And Ages Of M Dwarf Stars In Wide Binary Systems, Nicole M. Silvestri, Suzanne L. Hawley, Terry D. Oswalt

Aerospace, Physics, and Space Science Faculty Publications

We investigate the relationship between age and chromospheric activity for 139 M dwarf stars in wide binary systems with white dwarf companions. The age of each system is determined from the cooling age of its white dwarf component. The current limit for activity-age relations found for M dwarfs in open clusters is 4 Gyr. Our unique approach to finding ages for M stars allows for the exploration of this relationship at ages older than 4 Gyr. The general trend of stars remaining active for a longer time at a later spectral type is confirmed. However, our larger sample and greater …

Efficient Training Algorithms For A Class Of Shunting Inhibitory Convolutional Neural Networks, Fok Hing Chi Tivive, Abdesselam Bouzerdoum

Faculty of Informatics - Papers (Archive)

This article presents some efficient training algorithms, based on first-order, second-order, and conjugate gradient optimization methods, for a class of convolutional neural networks (CoNNs), known as shunting inhibitory convolution neural networks. Furthermore, a new hybrid method is proposed, which is derived from the principles of Quickprop, Rprop, SuperSAB, and least squares (LS). Experimental results show that the new hybrid method can perform as well as the Levenberg-Marquardt (LM) algorithm, but at a much lower computational cost and less memory storage. For comparison sake, the visual pattern recognition task of face/nonface discrimination is chosen as a classification problem to evaluate the …

An Analytical Study Of Peer-To-Peer Media Streaming Systems, Yi-Cheng Tu, Jianzhong Sun, Mohamed Hefeeda, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.

Provenance-Aware Tracing Of Worm Break-In And Contaminations: A Process Coloring Approach, Xuxian Kiang, Aaron Walters, Florian Buchholz, Dongyan Xu, Yi-Min Wang

Department of Computer Science Technical Reports

No abstract provided.

A Stochastic Calculus For Systems With Memory, Feng Yan, Salah-Eldin A. Mohammed

Articles and Preprints

For a given stochastic process X, its segment X_t at time t represents the "slice" of each path of X over a fixed time-interval [t-r, t], where r is the length of the "memory" of the process. Segment processes are important in the study of stochastic systems with memory (stochastic functional differential equations, SFDEs). The main objective of this paper is to study non-linear transforms of segment processes. Towards this end, we construct a stochastic integral with respect to the Brownian segment process. The difficulty in this construction is the fact that the …

Introduction (2005), Association Of Christians In The Mathematical Sciences

ACMS Conference Proceedings 2005

Fifteenth Conference of the Association of Christians in the Mathematical Sciences

Intrinsically Biased Electrocapacitive Catalysis, D. P. Sheehan, T. Seideman

Physics and Biophysics: Faculty Scholarship

We propose the application of the contact potential from metal-metal junctions or the built-in potential of semiconductor p-np-n junctions to induce or catalyze chemical reactions. Free of external sources, this intrinsic potential across microscale and nanoscale vacuum gaps establishes electric fields in excess of 10^7V/m. The electrostatic potential energy of these fields can be converted into useful chemical energy. As an example, we focus on the production of superthermal gas ions to drive reactions. Analysis indicates that this intrinsically biased electrocapacitive catalysis can achieve locally directed ion energies up to a few electron volts and local gas temperatureboosts in excess …

Coral Recruitment Patterns In The Florida Keys, Alison L. Moulding

Marine & Environmental Sciences Faculty Articles

This study examines scleractinian zooxanthellate coral recruitment patterns in the Florida Keys to determine if differences in density or community composition exist between regions. From July to September 2002, nine patch reefs, three in each of the upper, middle and lower Keys, were surveyed for coral recruits (colonies <5 cm in diameter) using randomly placed quadrats and transects. Coral recruits were enumerated, measured, and identified to genus. Fourteen genera of corals were observed across all sites and ranged from five to 13 per site. Densities ranged from 6.29 ± 1.92 (mean ± SE) to 39.08 ± 4.53 recruits m-2, and there were significant site and regional differences in recruit densities. The density of recruits in the upper Keys was significantly lower than in the middle and lower Keys. In addition, the upper Keys were less diverse and had a different recruit size-frequency distribution. The majority of recruits were non-massive scleractinian species that contribute relatively little to overall reef-building processes, a finding that is similar to previous studies. Fewer recruits of massive species were found in the upper Keys compared to the middle and lower Keys. The recruitment patterns of the reefs in the upper Keys could potentially hinder their ability to recover from stress and disturbances.

Ramanujan And The Regular Continued Fraction Expansion Of Real Numbers, James Mclaughlin, Nancy Wyshinski

Mathematics Faculty Publications

In some recent papers, the authors considered regular continued fractions of the form [a0; a, · · · , a | {z } m , a2 , · · · , a2 | {z } m , a3 , · · · , a3 | {z } m , · · · ], where a0 ≥ 0, a ≥ 2 and m ≥ 1 are integers. The limits of such continued fractions, for general a and in the cases m = 1 and m = 2, were given as ratios of certain infinite series. However, these formulae can be derived …

Two Sides Of The Same Coin: Bootstrapping The Restricted Vs. Unrestricted Model, Panagiotis Mantalos

Journal of Modern Applied Statistical Methods

The properties of the bootstrap test for restrictions are studied in two versions: 1) bootstrapping under the null hypothesis, restricted, and 2) bootstrapping under the alternative hypothesis, unrestricted. This article demonstrates the equivalence of these two methods, and illustrates the small sample properties of the Wald test for testing Granger-Causality in a stable stationary VAR system by Monte Carlo methods. The analysis regarding the size of the test reveals that, as expected, both bootstrap tests have actual sizes that lie close to the nominal size. Regarding the power of the test, the Wald and bootstrap tests share the same power …

Inferences About Regression Interactions Via A Robust Smoother With An Application To Cannabis Problems, Rand R. Wilcox, Mitchell Earleywine

Journal of Modern Applied Statistical Methods

A flexible approach to testing the hypothesis of no regression interaction is to test the hypothesis that a generalized additive model provides a good fit to the data, where the components are some type of robust smoother. A practical concern, however, is that there are no published results on how well this approach controls the probability of a Type I error. Simulation results, reported here, indicate that an appropriate choice for the span of the smoother is required so that the actual probability of a Type I error is reasonably close to the nominal level. The technique is illustrated with …