Physical Sciences and Mathematics Commons^™

A Peer-Tree Based Location Lookup Service In Mobile Wireless Networks, Jun Liu

Computer Science Faculty Publications

We present a location look-up service for aiding location-based routing in wireless networks with mobile hosts. This location look up service is constructed based on a peer-tree indexing structure which represents the friendship relations among mobile hosts. The friendship is derived from the relations of sharing various-length common suffixes of host identifiers. A friendship relation determines the cooperation relation among mobile hosts. The Peer-Tree indexing structure provides a guideline for propagating location updates and queries in an organized manner. Each host periodically propagates its up-to-date location to a small number of its friends. Location queries are forwarded to and serviced …

Local Charging Behavior On Gan Surfaces, Josephus Ferguson

Theses and Dissertations

Gallium nitride is an important III-V semiconductor which is used in many optoelectronic and high-frequency devices. The nature of the GaN surface and its electrical characteristics can impact the performance of such devices. In this study, several GaN surfaces are locally charged using an atomic force microscope, and then subsequently studied by measuring the surface potential with scanning Kelvin probe microscopy (SKPM). The charging and discharging behavior of the surface appears to be strongly influenced by surface preparation and the presence of a surface oxide layer. If a substantial oxide layer exists, then both positive and negative charging is possible …

Leveraging Virtualization For Performance Driven Development, Matthew Sullivan

Regis University Student Publications (comprehensive collection)

This thesis contains the research component of a software engineering study to create a .NET application performance testing lab, and several guided learning activities intended to teach the fundamentals of how to use it. In arriving upon the research which serves as the groundwork for this project, an introduction to the concepts of software performance, the risks associated with performances, and an approach to mitigating this risks called "performance driven development" is presented. This introduction is expanded by an overview of how performance is affected from application, network, database and presentation aspects. To address problems associated with performance in .NET …

Image Segmentation And Analysis For Automated Classification Of Traumatic Pelvic Injuries, Simina Vasilache

Theses and Dissertations

In the past decades, technical advances have allowed for the collection and storage of more types and larger quantities of medical data. The increase in the volume of existing medical data has increased the need for processing and analyzing such data. Medical data holds information that is invaluable for diagnostic as well as treatment planning purposes. Presently, a large portion of the data is not optimally used towards medical decisions because information contained in the data is inaccessible through simple human inspection, or traditional computational methods. In the field of trauma medicine, where caregivers are frequently confronted with situations where …

Introduction To Selecting Subsets Of Traits For Quantitative Trait Loci Analysis, Tilman Achberger, James C. Fleet, David E. Salt, R. W. Doerge

Conference on Applied Statistics in Agriculture

Quantitative trait loci (QTL) mapping is a popular statistical method that is often used in agricultural applications to identify genomic regions associated with phenotypic traits of interest. In its most common form, a QTL analysis tests one phenotypic trait at a time using a variety of research hypotheses that depend on the application. When multiple traits are available, there are considerable benefits to analyzing subsets of biologically related traits in a multipletrait QTL mapping framework. Determining the most informative subset(s) of traits is the critical challenge that we address in this work. We present our approach, as well as simulations …

After Further Review: An Update On Modeling And Design Strategies For Agricultural Dose-Response Experiments, M. J. Frenzel, W. W. Stroup, E. T. Paparozzi

Conference on Applied Statistics in Agriculture

Research investigating dose-response relationships is common in agricultural science. This paper is an expansion on previous work by Guo, et al. (2006) motivated by plant nutrition research in horticulture. Plant response to level of nutrient applied is typically sigmoidal, i.e. no response at very low levels, observable response at mid-levels, point-of-diminishing returns and plateau at high levels. Plant scientists need accurate estimates of these response relationships for many reasons, including determining the lower threshold below which plants show deficiency symptoms and the point of diminishing returns, above which excessive doses are economically and environmentally costly. Guo et al. presented models …

A Non-Parametric Empirical Bayes Approach For Estimating Transcript Abundance In Un-Replicated Next-Generation Sequencing Data, Sanvesh Srivastava, R. W. Doerge

Conference on Applied Statistics in Agriculture

Empirical Bayes approaches have been widely used to analyze data from high throughput sequencing devices. These approaches rely on borrowing information available for all the genes across samples to get better estimates of gene level expression. To date, transcript abundance in data from next generation sequencing (NGS) technologies has been estimated using parametric approaches for analyzing count data, namely – gamma-Poisson model, negative binomial model, and over-dispersed logistic model. One serious limitation of these approaches is they cannot be applied in absence of replication. The high cost of NGS technologies imposes a serious restriction on the number of biological replicates …

Nonlinear Regression Parameters As Outcomes: Simple Vs. Sophisticated Analyses, Reid D. Landes

Conference on Applied Statistics in Agriculture

Sometimes a nonlinear regression parameter for an individual is the outcome of interest. But due to variability among individuals, the individuals’ regression parameters cannot be estimated with the same amount of precision. This problem of heterogeneous variance complicates the ultimate goal of estimating population-level regression parameters with two usual methods: (i) the simple arithmetic mean of individually estimated regression parameters and (ii) random coefficients regression (RCR). Weights are proposed for each method to account for the heterogeneity problem. The methods are illustrated with chick weights collected over time. Monte Carlo simulation allows comparison of statistical properties of the four estimators …

Approximate Bayesian Approaches For Reverse Engineering Biological Networks, Andrea Rau, Florence Jaffr´Ezic, Jean-Louis Foulley, R. W. Doerge

Conference on Applied Statistics in Agriculture

Genes are known to interact with one another through proteins by regulating the rate at which gene transcription takes place. As such, identifying these gene-to-gene interactions is essential to improving our knowledge of how complex biological systems work. In recent years, a growing body of work has focused on methods for reverse-engineering these so-called gene regulatory networks from time-course gene expression data. However, reconstruction of these networks is often complicated by the large number of genes potentially involved in a given network and the limited number of time points and biological replicates typically measured. Bayesian methods are particularly well-suited for …

On Testing For Significant Quantitative Trait Loci (Qtl) Effects When Variances Are Unequal, Pradeep Singh, Shesh N. Rai

Conference on Applied Statistics in Agriculture

The basic theory of QTL (Quantitative Trait Loci) mapping is to score a population for a quantitative trait according to the marker genotype, and then to use statistics to identify differences associated with the markers and the quantitative trait of interest. Permutation based methods have been used to estimate threshold values for quantitative mapping. The permutation test based on the Student t-test for equality of means does not control Type I error rate to its nominal value when variances are unequal. In this study we propose a modification of the Student t-test based on the jackknife estimator of population variance. …

Functional Divergence Of Duplicated Genes In The Soybean Genome, Paul L. Auer, R. W. Doerge

Conference on Applied Statistics in Agriculture

The soybean genome has undergone many different evolutionary changes that are observable with modern technologies. Of particular interest to scientists and plant breeders is the fact that the soybean genome exhibits features of genome duplication from millions of years ago. Genes that were copied during the duplication event have since diverged functionally. Identifying functionally divergent duplicate genes may provide insight into the evolution of soybean. To investigate functional divergence, transcripts from seven different tissue samples of pooled soybean messenger RNA were sequenced using the Solexa next-generation sequencer and analyzed for gene expression. We tested differential expression of duplicated genes within …

Generalized Linear Mixed Model Estimation Using Proc Glimmix: Results From Simulations When The Data And Model Match, And When The Model Is Misspecified, Debbie Boykin, Mary J. Camp, Luann Johnson, Matthew Kramer, David Meek, Debra Palmquist, Bryan Vinyard, Mark West

Conference on Applied Statistics in Agriculture

A simulation study was conducted to determine how well SAS® PROC GLIMMIX (SAS Institute, Cary, NC), statistical software to fit generalized linear mixed models (GLMMs), performed for a simple GLMM, using its default settings, as a naïve user would do. Data were generated from a wide variety of distributions with the same sets of linear predictors, and under several conditions. Then, the data sets were analyzed by using the correct model (the generating model and estimating model were the same) and, subsequently, by misspecifying the estimating model, all using default settings. The data generation model was a randomized complete block …

Using Time-Series Intervention Analysis To Model Cow Heart Rate Affected By Programmed Audio And Environmental/Physiological Cues, Dean M. Anderson, Norbert Remenyi, Leigh W. Murray

Conference on Applied Statistics in Agriculture

This research is the first use of Box-Jenkins time-series models to describe changes in heart rate (HR) of free-ranging crossbred cows (Bos taurus) receiving both programmed audio cues from directional virtual fencing (DVFTM) devices and non-programmed environmental/physiological cues. The DVFTM device is designed to control the animal's location on the landscape. Polar Accurex® devices were used to capture HR every minute between 19 and 24 March 2003, when three mature free-ranging beef cows, previously habituated to the DVFTM device, were confined to a brush-infested area of an arid rangeland paddock. Global positioning system (GPS) electronics were used to record each …

A Generalized Approach And Computer Tool For Quantitative Genetics Study, Jixiang Wu, Johnie N. Jenkins, Jack C. Mccarty

Conference on Applied Statistics in Agriculture

Quantitative genetics is one of the most important components to provide valuable genetic information for improving production and quality of plants and animals. The research history of quantitative genetics study could be traced back more than one hundred years. Since the Analysis of Variance (ANOVA) methods were proposed by Fisher in 1925, several useful genetic models have been proposed and have been widely applied in both plant and animal quantitative genetics studies. Useful examples included various North Carolina (NC) and diallel cross mating designs. However, many genetic models derived from these mating designs are ANOVA method based, so there are …

Modeling Dna Methylation Tiling Array Data, Gayla Olbricht, Bruce A. Craig, R. W. Doerge

Conference on Applied Statistics in Agriculture

Epigenetics is the study of heritable changes in gene function that occur without a change in DNA sequence. It has quickly emerged as an essential area for understanding inheritance and variation that cannot be explained by the DNA sequence alone. Epigenetic modifications have the potential to regulate gene expression and may play a role in diseases such as cancer. DNA methylation is a type of epigenetic modification that occurs when a methyl chemical group attaches to a cytosine base on the DNA molecule. To better understand this epigenetic mechanism, DNA methylation profiles can be constructed by identifying all locations of …

Characterizing Thermal Hysteresis In Body Temperature For A Heat Stressed Steer, F. Yang, A. M. Parkhurst, D. A. Spiers, J. B. Gaughan, T. L. Mader, G. L. Hahn

Conference on Applied Statistics in Agriculture

Studies have shown that exposure of animals to a high ambient temperature environment poses serious threats to their health, performance and productivity. Above a certain threshold an animal's body temperature (Tb) appears to be driven by the hot ambient temperature (Ta). For steers challenged by heat stress, the Tb-Ta relationship shows a dramatic increase in Tb per unit change of Ta and the dynamics of the Tb-Ta relationship follow a pattern which depends on whether Ta is increasing or decreasing. A delay becomes noticeable in a steer’s thermo-regulatory response to Ta when Ta is controlled to be sinusoidal in the …

Evaluating Pen-Day Interactions In Body Temperature Bilogistic Mixed Model For Handling Of Feedlot Heifers During Heat Stress, F. Yang, A. M. Parkhurst, T. M. Brown-Brandl, R. A. Eigenberg, J. A. Nienaber

Conference on Applied Statistics in Agriculture

Daily activities consume the energy of heifers, subsequently causing an elevation of body temperature, depending on the ambient conditions. A better understanding of the dynamics of body temperature (Tb) would be helpful when deciding how to process and handle heifers. It would also lead to specific recommendations on moving heifers under different ambient conditions, especially during the summer. In this study, a bilogistic mixed model is used to describe the dynamics of Tb during the moving event. Data was taken from heifers in pens located at different distances from the heifer work station on four separate summer days under hot …

Characterizing Foraging Patterns Among Cattle And Bonded And Non-Bonded Small Ruminants Using Spatial Point Process Techniques, D. M. Anderson, L. W. Murray, P. Sun, E. L. Fredrickson, R. E. Estell, V. B. Nakamatsu

Conference on Applied Statistics in Agriculture

This paper uses the technique of spatial point processes to describe the spatial patterns of freeranging cattle and small ruminants. Two mixed-species livestock groups were monitored while foraging on 410 ha of brush-infested Southern New Mexico rangeland during July and August 1988. The groups consisted of crossbred Bos taurus and Bos indicus beef cattle with white-faced sheep (Ovis aries) and mohair goats (Capra hircus). The bonded group consisted of small ruminants that had their behaviours modified through socialization with cattle to form a ‘flerd’ in which small ruminants consistently remained near cattle. Small ruminants in the non-bonded group had not …

Modeling Fish Length Distribution Using A Mixture Technique, Bahman Shafii, William J. Price, Charlie Holderman, Cathy Gidley, Paul J. Anders

Conference on Applied Statistics in Agriculture

In fisheries science, length and age are important aspects of fish life history. Length is a function of growth, which provides an integrated measure of the environmental and endogenous conditions, e.g. genetics, affecting individuals and populations. Length at age data can be used to assess quality and quantity of habitat, food availability, or the need for and influence of management activities. Statistical mixture techniques may be used as a means to effectively model fish length distribution. A three-component mixture model, based on normal variates, was employed to describe length distribution in mountain whitefish species. The resulting model provided parameter estimates …

Editor's Preface And Table Of Contents, Weixing Song

Conference on Applied Statistics in Agriculture

These proceedings contain papers presented in the twenty-second annual Kansas State University Conference on Applied Statistics in Agriculture, held in Manhattan, Kansas, April 25 - April 27, 2010.

Memristics: Memristors, Again? – Part Ii, How To Transform Wired ‘Translations’ Between Crossbars Into Interactions?, Rudolf Kaehr

Rudolf Kaehr

The idea behind this patchwork of conceptual interventions is to show the possibility of a “buffer-free” modeling of the crossbar architecture for memristive systems on the base of a purely difference-theoretical approach. It is considered that on a nano-electronic level principles of interpretation appears as mechanisms of complementarity. The most basic conceptual approach to such a complementarity is introduced as an interchangeability of operators and operands of an operation. Therefore, the architecture of crossbars gets an interpretation as complementarity between crossbar functionality and “buffering” translation functionality. That is, the same matter functions as operator and at once, as operand – …

Experimental Manipulation Of Interfacial Molecular Assemblies, Mark Anderson

Mark R. Anderson

No abstract currently available.

The Effect Of Ion-Pairing On The Open Circuit Potential Of 3-Mercaptoproprionic Acid Modified Gold Electrodes, Mark Anderson, Alice Harper

Mark R. Anderson

Open circuit potential (OCP) measurement is used to monitor the charge of a monolayer of 3-mercaptopropionic acid. OCP is determined by the concentrations of the reduced and oxidized forms of a redox couple in the solution adjacent to the modified interface. OCP values were monitored in the presence of the one-electron redox couple Fe(CN)63-/4- as a function of solution pH. The OCP measured at basic pHs was different from the acidic OCP due to differences in electrostatic interactions between the interface and the redox species as described by the Nernst equation. The influence of ion-pairing with the monolayer is studied …

Influence Of Canopy Cover, Nutrients, And Season On Stoichiometric Variation Of Epilithon In Neotropical Streams., Tyler J. Kohler

School of Natural Resources: Dissertations, Theses, and Student Research

Light and nutrient availability are strong factors determining the nutrient composition of epilithon in temperate stream ecosystems. However, little work has been performed regarding this association in tropical streams. In our study, we investigated 1) how gradients of canopy cover and nutrients and 2) wet/dry seasonality influence epilithon standing stocks and nutrient quality. We surveyed 18 stream locations within six watersheds that varied in nutrient and light conditions during both the wet and dry seasons on the island of Trinidad to test these questions. Additionally, we sampled four stream reaches bimonthly for three years, thinning the canopy of two of …

2010 Sonia Kovalevsky Math For Girls Day Report, Association For Women In Mathematics, Lincoln University Of Missouri, Donna L. Stallings

Math for Girls Day Documents

Report for the Fifth Annual Lincoln University Sonia Kovalevsky Math for Girls Day that was held on April 23, 2010 from 8:00am to 2:00pm on the campus of Lincoln University in Jefferson City, MO.

Not Empty, Lauren Orme

Scripps Senior Theses

Not Empty is a two- part exploration of the relationship between humans and nature. In this essay I intend to discuss the relationship Australian Aboriginal peoples have with their environment. Their many cultures are among the oldest surviving civilizations on the planet, and their natural history is rich and complex. I plan to compare the relationship Australian Aboriginal cultures have to their environment to that of a Western civilization, specifically the United States. Neither relationship is perfect, nor is one of them 'better.' Both have histories riddled with extinction, evolution, and the conquest of new lands. The struggle Aboriginal Australians …

Classification, Synthesis And Characterization Of Pyridyl Porphyrin Frameworks, Lucas D. Devries

Department of Chemistry: Dissertations, Theses, and Student Research

CLASSIFICATION, SYNTHESIS AND CHARACTERIZATION OF PYRIDYL PORPHYRIN FRAMEWORKS

Lucas D. DeVries, M.S. University of Nebraska, 2010 Adviser: Wonyoung Choe

Structural analysis of a solid-state material is vital because the structure often determines the physical (or chemical) properties of the material. An understanding of the relationship between structural components and bulk properties can be used to design materials with specific properties. To achieve such understanding, two things are required: a rigorous structural analysis method and a study of the properties of materials with noteworthy structural features.

In this thesis, the author reviews 44 pyridyl porphyrin frameworks in an effort to determine …

A Numerical Method For Estimating The Variance Of Age At Maximum Growth Rate In Growth Models, Semhar Ogbagaber

Theses and Dissertations

Most studies on maturation and body composition using the Fels Longitudinal data mention peak height velocity (PHV) as an important outcome measure. The PHV is often derived from growth models such as the triple logistic model fitted to the stature (height) data. The age at PHV is sometimes ordinalized to designate an individual as an early, average or late maturer. In theory, age at PHV is the age at which the rate of growth reaches the maximum. Theoretically, for a well behaved growth function, this could be obtained by setting the second derivative of the growth function to zero and …

Fundamental Work Toward An Image Processing-Empowered Dental Intelligent Educational System, Grace Olsen

Theses and Dissertations

Computer-aided education in dental schools is greatly needed in order to reduce the need for human instructors to provide guidance and feedback as students practice dental procedures. A portable computer-aided educational system with advanced digital image processing capabilities would be less expensive than current computer-aided dental educational systems and would also address some of their limitations. This dissertation outlines the development of novel components that would be part of such a system. This research includes the design of a novel image processing technique, the Directed Active Shape Model algorithm, which is used to locate the tooth and drilled preparation from …

Scalar Waves In An Almost Cylindrical Spacetime, Joseph Gordon

Theses and Dissertations

The scalar wave equation is investigated for a scalar field propagating in a spacetime background ds²=e^{2a}(-dt²+dr²)+R(e^{-2ψ}dφ²+e^{2ψ}dz²). The metric is compactified in the radial direction. The spacetime slices of constant φ and z are foliated into outgoing null hypersurfaces by the null coordinate transformation u=t-r. The scalar field imitates the amplitude behavior of a light ray, or a gravitational wave, traveling along a null hypersurface when the area function R is a constant or is a function of u. These choices for R restrict the gravitational wave factor ψ to being an arbitrary function of u.