Physical Sciences and Mathematics Commons^™

University Of North Florida Greenhouse Gas Emissions Inventory And Projections 2009, Radha Pyati, Katrina Norbom, Megan Walker-Radtke

Campus Sustainability

This report describes the 2009 greenhouse gas emissions inventory of the University of North Florida. Such inventories are becoming more important as society approaches restrictions on carbon dioxide emissions due to their effects on global warming. Greenhouse gas emissions inventories have been conducted on hundreds of campuses in the United States, as well as thousands of other organizations worldwide, including U.S. private corporations. An inventory like this generally forms the initial baseline for a campus climate action plan. Climate action plans have also been created by hundreds of universities and other entities. Following the release of this report, a UNF …

Oxygen And Hydrogen Isotope Fractionation In Serpentine–Water And Talc–Water Systems From 250 To 450°C Mpa, Peter Saccocia, J. S. Seewald, W. C. Shanks Iii

Geological Sciences Faculty Publications

Oxygen and hydrogen isotope fractionation factors in the talc–water and serpentine–water systems have been determined by laboratory experiment from 250 to 450 °C at 50 MPa using the partial exchange technique. Talc was synthesized from brucite + quartz, resulting in nearly 100% exchange during reaction at 350 and 450 °C. For serpentine, D–H exchange was much more rapid than ¹⁸O–¹⁶O exchange when natural chrysotile fibers were employed in the initial charge. In experiments with lizardite as the starting charge, recrystallization to chrysotile enhanced the rate of ¹⁸O–¹⁶O exchange with the coexisting aqueous phase. Oxygen …

Stereoscopic Display Technology For Visualizing Vascular Structures, Thomas Wischgoll

Computer Science and Engineering Faculty Publications

No abstract provided.

Periodic Traveling Waves In Sirs Endemic Models, Tong Li, Yi Li, Herbert W. Hethcote

Mathematics and Statistics Faculty Publications

Mathematical models are used to determine if infection wave fronts could occur by traveling geographically in a loop around a region or continent. These infection wave fronts arise by Hopf bifurcation for some spatial models for infectious disease transmission with distributed-contacts. Periodic traveling waves are shown to exist for the spatial analog of the SIRS endemic model, in which the temporary immunity is described by a delay, but they do not exist in a similar spatial SIRS endemic model without a delay. Specifically, we found that the ratio of the delay ω in the recovered class and the average infectious …

A Direct Solution Of The Robin Inverse Problem, Weifu Fang, Suxing Zeng

Mathematics and Statistics Faculty Publications

We present a direct, linear boundary integral equation method for the inverse problem of recovering the Robin coefficient from a single partial boundary measurement of the solution to the Laplace equation.

A Note On The Positive Solutions Of An Inhomogeneous Elliptic Equation On Rn, Yinbin Deng, Yi Li, Fen Yang

Mathematics and Statistics Faculty Publications

This paper is contributed to the elliptic equation

(0.1) Δu+K(|x|)up+μf(|x|)=0,

where p>1, x∈Rn, n⩾3, and μ⩾0 is a constant. We study the structure of positive radial solutions of (0.1) and obtain the uniqueness of solution decaying faster than r−m at ∞ if μ is small enough under some assumptions on K and f, where m is the slow decay rate.

Ontologies And Rules, Pascal Hitzler, Bijan Parsia

Computer Science and Engineering Faculty Publications

Ontologies and rules are two established paradigms in knowledge modelling, and play an important role for the Semantic Web. In this chapter, we present an introduction to common approaches for combining OWL ontologies and rules. In particular, we cover the Semantic Web Rules Language SWRL and Description Logic Programs DLP, and give pointers to the literature.

Gravity Waves From Tachyonic Preheating After Hybrid Inflation, Jean-François Dufaux, Gary Felder, Lev Kofman, Navros Olga

Physics: Faculty Publications

We study the stochastic background of gravitational waves produced from preheating in hybrid inflation models. We investigate different dynamical regimes of preheating in these models and we compute the resulting gravity wave spectra using analytical estimates and numerical simulations. We discuss the dependence of the gravity wave frequencies and amplitudes on the various potential parameters. We find that large regions of the parameter space leads to gravity waves that may be observable in upcoming interferometric experiments, including Advanced LIGO, but this generally requires very small coupling constants.

Cascade Of Magnetic-Field-Induced Quantum Phase Transitions In A Spin- 12 Triangular-Lattice Antiferromagnet, Nathanael Alexander Fortune, Scott T. Hannahs, Y. Yoshida, T. Sherline, T. Ono, H. Tanaka, Y. Takano

Physics: Faculty Publications

We report magnetocaloric and magnetic-torque evidence that in Cs2CuBr4—a geometrically frustrated Heisenberg S 1⁄4 12 triangular-lattice antiferromagnet—quantum fluctuations stabilize a series of spin states at simple increasing fractions of the saturation magnetization Ms. Only the first of these states—at M 1⁄4 13 Ms—has been theoretically predicted. We discuss how the higher fraction quantum states might arise and propose model spin arrangements. We argue that the first-order nature of the transitions into those states is due to strong lowering of the energies by quantum fluctuations, with implications for the general character of quantum phase transitions in geometrically frustrated systems.

Dynamical Fluctuations In Dense Granular Flows, Emily Gardel, E. Seitaridou, Kevin Facto, E. Keene, K. Hattam, Nalini Easwar, Narayanan Menon

Physics: Faculty Publications

We have made measurements of force and velocity fluctuations in a variety of dense, gravity-driven granular flows under flow conditions close to the threshold of jamming. The measurements reveal a microscopic state that evolves rapidly from entirely collisional to largely frictional, as the system is taken close to jamming. On coarse-grained time scales, some descriptors of the dynamics—such as the probability distribution of force fluctuations, or the mean friction angle—do not reflect this profound change in the micromechanics of the flow. Other quantities, such as the frequency spectrum of force fluctuations, change significantly, developing low-frequency structure in the fluctuations as …

Winds And Accretion In Young Stars, Suzan Edwards

Astronomy: Faculty Publications

Establishing the origin of accretion powered winds from forming stars is critical for understanding angular momentum evolution in the star‐disk interaction region. Here, the high velocity component of accretion powered winds is launched and accreting stars are spun down, in defiance of the expected spin‐up during magnetospheric accretion. T Tauri stars in the final stage of disk accretion offer a unique opportunity to study the connection between accretion and winds and their relation to stellar spindown. Although spectroscopic indicators of high velocity T Tauri winds have been known for decades, the line of He I 10830 offers a promising new …

The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Joshua D. Younger, Giovanni G. Fazio, Jia Sheng Huang, Min S. Yun, Grant W. Wilson, Matthew L.N. Ashby, Mark A. Gurwell, Alison B. Peck, Glen R. Petitpas, David J. Wilner, David H. Hughes, Itziar Aretxaga, Sungeun Kim, Kimberly S. Scott, Jason Austermann, Thushara Perera, James D. Lowenthal

Astronomy: Faculty Publications

We present results from a continuing interferometric survey of high-redshift submillimeter galaxies (SMGs) with the Submillimeter Array, including high-resolution (beam size ∼ 2 arcsec) imaging of eight additional AzTEC 1.1 mm selected sources in the COSMOS field, for which we obtain six reliable (peak signal-to-noise ratio (S/N) >5 or peak S/N >4 with multiwavelength counterparts within the beam) and two moderate significance (peak S/N >4) detections. When combined with previous detections, this yields an unbiased sample of millimeter-selected SMGs with complete interferometric follow up. With this sample in hand, we (1) empirically confirm the radio-submillimeter association, (2) examine the submillimeter …

Ethyl 1-Acetyl-1h-Indole-3-Carboxyl­Ate, Tasneem Siddiquee, Shahid Islam, Dennis Bennett, Matthias Zeller, Mahmun Hossain

Chemistry Faculty Research

The title compound, C₁₃H₁₃NO₃, was synthesized by acetyl­ation of ethyl 1H-indole-3-carboxyl­ate. The aromatic ring system of the mol­ecule is essentially planar, but the saturated ethyl group is also located within this plane and the overall r.m.s. deviation from planarity is only 0.034 Å. Pairs of C-HO inter­actions connect mol­ecules into chains along the diagonal of the unit cell. Mol­ecules also form weakly connected dimers via stacking inter­actions of the indole rings with centroid-centroid separations of 3.571 (1) Å. C-H inter­actions between methyl­ene and methyl groups and the indole and benzene ring complete …

On The Number Of K-Gons In Finite Projective Planes, Felix Lazebnik, Keith Mellinger, Oscar Vega

Mathematics

Let π = πq denote a finite projective plane of order q, and let G = Levi(π) be the bipartite point-line incidence graph of π. For k ≥ 3, let c2k(π) denote the number of cycles of length 2k in G. Are the numbers c2k(π) the same for all πq? We prove that this is the case for k = 3, 4, 5, 6 by computing these numbers.

Does The Mg/Ca In Foraminifera Tests Provide A Reliable Temperature Proxy?, Sarah Clark, Figen Mekik

Student Summer Scholars Manuscripts

The Mg/Ca in foraminifera shells is commonly used as a proxy to estimate ocean temperatures in Earth’s past. However, studies have shown that both dissolution and salinity influence the Mg/Ca in shells of tropical foraminifera, which can cause paleotemperature estimates to be inaccurate. We measured Mg/Ca in shells of Globigernoides ruber and Globigerinoides sacculifer from core tops in the eastern equatorial Pacific. We compared our results with global core top data, which paleotemperature equations have been calibrated and published. We find that Mg/Ca values range greatly at the same surface ocean temperature. We also find that salinity and dissolution do …

Modeling Problem Solving: Creating And Evaluating, Kaitlin M. Downey, Nathan Barrows

Student Summer Scholars Manuscripts

The purpose of this project was to create novice-level screencasts and to investigate students’ perceptions and usage of them. A survey of 61 general chemistry students revealed polarity, Lewis structures, molecular geometry, and bond polarity to be topics of greatest concern. Over 25 screencasts were created using Camtasia Studio software and a Dell TabletPC. A blog (http://mi-chemed.net) was created to host the tutorials and monitor student usage. After students registered and logged in to the blog, their viewing patterns were recorded. They were encouraged to comment on the content and technical features of the videos (e.g. animations). Online comments and …

Emissions From Biomass Burning In The Yucatan, Robert J. Yokelson, J. D. Crounse, P. F. Decarlo, T. Karl, S. P. Urbanski, E. Atlas, T. Campos, Y. Shinozuka, V. Kasputin, A. D. Clarke, A. Weinheimer, D. J. Knapp, D. D. Montzka, J. Holloway, P. Weibring, F. Flocke, W. Zheng, D. Toohey, P. O. Wennberg, C. Wiedinmyer, L. Mauldin, A. Fried, D. Richter, J. Walega, J. L. Jimenez, K. Adachi, P. R. Buseck, S. R. Hall, R. Shetter

Chemistry and Biochemistry Faculty Publications

In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle species were measured from 20 deforestation and crop residue fires on the Yucatan peninsula. This included two trace gases useful as indicators of BB (HCN and acetonitrile) and several rarely, or never before, measured species: OH, peroxyacetic acid, propanoic acid, hydrogen peroxide, …

Biomass Burning And Urban Air Pollution Over The Central Mexican Plateau, J. D. Crounse, P. F. Decarlo, Donald R. Blake, L. K. Emmons, T. L. Campos, E. C. Apel, A. D. Clarke, A. J. Weinheimer, D. C. Mccabe, Robert J. Yokelson, J. L. Jimenez, P. O. Wennberg

Chemistry and Biochemistry Faculty Publications

Observations during the 2006 dry season of highly elevated concentrations of cyanides in the atmosphere above Mexico City (MC) and the surrounding plains demonstrate that biomass burning (BB) significantly impacted air quality in the region. We find that during the period of our measurements, fires contribute more than half of the organic aerosol mass and submicron aerosol scattering, and one third of the enhancement in benzene, reactive nitrogen, and carbon monoxide in the outflow from the plateau. The combination of biomass burning and anthropogenic emissions will affect ozone chemistry in the MC outflow.

Loop Dynamics Of The Extracellular Domain Of Human Tissue Factor And Activation Of Factor Viia, Agnese S. Minazzo, Reuben C. Darlington, J. B. A. Ross

Chemistry and Biochemistry Faculty Publications

In the crystal structure of the complex between the soluble extracellular domain of tissue factor (sTF) and activesite- inhibited VIIa, residues 91 and 92 in the Pro⁷⁹-Pro⁹² loop of sTF interact with the catalytic domain of VIIa. It is not known, however, whether this loop has a role in allosteric activation of VIIa. Time-resolved fluorescence anisotropy measurements of probes covalently bound to sTF mutants E84C and T121C show that binding uninhibited Factor VIIa affects segmental motions in sTF. Glu⁸⁴ resides in the Pro⁷⁹-Pro⁹² loop, and Thr¹²¹ resides in the turn between the …

Logistic Models With Missing Categorical Covariates, Jeremiah Rounds

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

We present an EM based solution to missing categorical covariates in Binomial models with logit links using an assumption that experimental units are drawn from a Multinomial population of infinite size. We further address the problem of separation of points inducing large variances on parameter estimates by the use of a novel score-modification based on Firth's bias-reduction score-modification. We simulate to address questions about estimate bias, distribution, and appropriate parameter coverage by Wald intervals.

Approaches To Promote Active, Conceptual Learning In A Pedagogically Hybrid Introductory Statistics Course, Brittany L. Allred

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

Statistics education is an active area of research where discovery-based learning is becoming more prominent. This project reviews how the USEI and GAISE recommendations can be implemented in the statistics classroom. Further, the project describes the creation of a library of classroom materials for an introductory statistics course. The results are also discussed from implementing various library materials, along with the student response to hands-on learning techniques.

Intermediate-Complexity Biological Modeling Framework For Nutrient Cycling In Lakes Based On Physical Structure, Michael Clay Rigley

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

Mathematical models for the change in concentration of total dissolved nitrogen (TDN) in mountain lakes are developed based on the dynamics of coupled, well-mixed containers. Each includes a stratified lake structure without the complexity of a full fluid model. A lake is divided into a suite of compartments based on physical structure: warm upper layer (epilimnion), cold inflow and insertion layer (metalimnion), cold lower layer (hypolimnion), and a warm shallow shelf. With the compartments as the framework and literature values for uptake rates, death rates, half-saturation constants, and sinking rates, systems of equations are written for three models. The first …

The Statistical Evaluation Of Collective Risk Models With Various Distributional Assumptions, Chang Li

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

Our thesis includes 2 sections. In section 1, we mainly discuss the distribution function and the empirical simulation of the total claims amount for a portfolio with multiple distributional assumptions, under the collective risk model for a single period.

In section 2, we discuss the collective risk model for an extended period, which mainly deals with the amount of surplus over several periods of time. Let Un denote the surplus at time n, then we interested in the probability of ruin, that is, the probability that there exists an n such that Un< O. In this section, we put forward an algorithm for the probability of ruin (both theoretical and empirical) using this model, with various distributional assumptions, and compare the theoretical and empirical results.

The reference of this project is Actuarial …

Probe-Level Statistical Models For Differential Expression Of Genes In Bovine Nt Studies, Jason L. Bell

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

A brief introduction of microarray technology and its uses is given. This technology is commonly used in agricultural research, including research in nuclear transfer, which motivated this study. There are 3 classes of statistical models compared: probeset-level, weighted probeset-level and probe-level.

Different statistical mod els are compared on 3 spike-in experiments to assess the relative performance in identifying differentially expressed genes . A novel nested factorial model was found to outperform all other models compared in this study in one spike-in experiment, and was found to be competitive in its performance relative to the other models on the other spike-in …

Comparison Of Random Forests And Cforest: Variable Importance Measures And Prediction Accuracies, Rong Xia

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

Random forests are ensembles of trees that give accurate predictions for regression, classification and clustering problems. The CART tree, the base learn er employed by random forests, has been criticized because of bias in the selection of splitting variables. The performance of random forests is suspect due to this criticism. A new implementation of random forests, Cforest, which is claimed to outperform random forests in both predictive power and variable importance measures , was developed based on Ctree, an implementation of conditional inference trees.

We address the underlying mechanism of random forests and Cforest in this report. Comparison of random …

Folklore And The Internet: Vernacular Expression In A Digital World, Trevor J. Blank

All USU Press Publications

Folklore and the Internet is a pioneering examination of the folkloric qualities of the World Wide Web, e-mail, and related digital media. It shows that folk culture, sustained by a new and evolving vernacular, has been a key, since the Internetýs beginnings, to language, practice, and interaction online. Users of many sorts continue to develop the Internet as a significant medium for generating, transmitting, documenting, and preserving folklore. In a set of new, insightful essays, contributors Trevor J. Blank, Simon J. Bronner, Robert Dobler, Russell Frank, Gregory Hansen, Robert Glenn Howard, Lynne S. McNeill, Elizabeth Tucker, and William Westerman showcase …

Landscaping On The New Frontier: Waterwise Design For The Intermountain West, Susan E. Meyer, Roger K. Kjelgren, Darrel G. Morrison, William A. Varga

All USU Press Publications

A practical volume for the home or business owner on landscaping with native, drought-tolerant plants in the Rocky Mountain West. Filled with color illustrations, photos, and design sketches, over 100 native species are described, while practical tips on landscape design, water-wise irrigation, and keeping down the weeds are provided. In this book you will learn how to use natural landscapes to inspire your own designed landscape--around your business or home and yard. Included are design principles, practical ideas, and strong examples of what some homeowners have already done to convert traditional "bluegrass" landscapes into ones that are more expressive of …

A Comparison Of The Rule And Case-Based Reasoning Approaches For The Automation Of Help-Desk Operations At The Tier-Two Level, Michael Forrester Bryant

CCE Theses and Dissertations

This exploratory study investigates the hypothesis that case-based reasoning (CBR) systems have advantages over rule-based reasoning (RBR) systems in providing automated support for Tier-2 help desk operations. The literature suggests that rule-based systems are best suited for problem solving when the system being analyzed is a single-purpose, specialized system and the rules for solving the problems are clear and do not change with high frequency. Case-based systems, because of their ability to offer alternative solutions for a given problem, give help-desk technicians more flexibility. Specifically, this dissertation aims to answer the following questions:

1. Which paradigm, rule-based or case-based reasoning, …

An Analysis Of The Impact Of Information Security Policies On Computer Security Breach Incidents In Law Firms, Faith M. Heikkila

CCE Theses and Dissertations

Law firms maintain and store voluminous amounts of highly confidential and proprietary data, such as attorney-client privileged information, intellectual properties, financials, trade secrets, personal, and other sensitive information. There is an ethical obligation to protect law firm client data from unauthorized access. Security breaches jeopardize the reputation of the law firm and could have a substantial financial impact if these confidential data are compromised. Information security policies describe the security goals of a law firm and the acceptable actions and uses of law firm information resources.

In this dissertation investigation, the author examined the problem of whether information security policies …

A Study Of First- And Continuing-Generation College Students' Use Of Internet Communication Technologies In Social Capital And Its Contribution To Their Persistence In College, Gail Dianne (Hodge) Hayes

CCE Theses and Dissertations

Prior studies have shown that students who are the first in their families to attend college fail to persist in college more so than their continuing-generation (CG) counterparts do. Prior research on this phenomenon has helped to identify various factors that contribute to the lower college persistence of first-generation (FG) students. For example, social capital has been identified as a factor that improves student persistence in college. Prior studies have shown that FG students tend to enter college with lower social capital than their CG student counterparts do. Additionally, while in school, FG students tend not to engage in behaviors …