Physical Sciences and Mathematics Commons^™

Principal Angles And Approximation For Quaternionic Projections [Dataset], Terry A. Loring

Math and Statistics Datasets

We extend Jordan's notion of principal angles to work for two subspaces of quaternionic space, and so have a method to analyze two orthogonal projections in the matrices over the real, complex or quaternionic field (or skew field). From this we derive an algorithm to turn almost commuting projections into commuting projections that minimizes the sum of the displacements of the two projections. We quickly prove what we need using the universal real C*-algebra generated by two projections.

Estimating Norms Of Commutators [Dataset], Terry A. Loring, Freddy Vides

Math and Statistics Datasets

We find estimates on the norm of a commutator of the form [f(x),y] in terms of the norm of [x,y], assuming that x and y are bounded linear operators on Hilbert space, with x normal and with spectrum within the domain of f. In particular we discuss |[x^2,y]| and |[x^{1/2},y]| for 0leq x leq 1. For larger values of delta = |[x,y]| we can rigorous calculate the best possible upper bound |[f(x),y]| leq eta_f(delta) for many f. In other cases we have conducted numerical experiments that strongly suggest that we have in many cases found the correct formula for the …

Computing A Logarithm Of A Unitary Matrix With General Spectrum [Dataset], Terry A. Loring

Math and Statistics Datasets

We analyze an algorithm for computing a skew-Hermitian logarithm of a unitary matrix, and also skew-Hermitian approximate logarithms for nearly unitary matrices. This algorithm is very easy to implement using standard software and it works well even for unitary matrices with no spectral conditions assumed. Certain examples, with many eigenvalues near -1, lead to very non-Hermitian output for other basic methods of calculating matrix logarithms. Altering the output of these algorithms to force an Hermitian output creates accuracy issues which are avoided by the considered algorithm. A modification is introduced to deal properly with the J-skew symmetric unitary matrices. Applications …

Leslie Matrices For Logistic Population Modeling, Bruce Kessler

Mathematics Faculty Publications

Leslie matrices are taught as a method of modeling populations in a discrete-time fashion with more detail in the tracking of age groups within the population. Leslie matrices have limited use in the actual modeling of populations, since when the age groups are summed, it is basically equivalent to discrete-time modeling assuming exponential population growth. The logistic model of population growth is more realistic, since it takes into account a carrying capacity for the environment of the population. This talk will describe an adjustment to the Leslie matrix approach for population modeling that is both takes into account the carrying …

Controls On Particle Settling Velocity And Bed Erodibility In The Presence Of Muddy Flocs And Biologically Packaged Pellets: Modeling Study Utilizing The York 3-D Hydrodynamic Cohesive Bed Model, K. A. Fall, Courtney K. Harris, Carl T. Friedrichs, J. P. Rinehimer

Presentations

No abstract provided.

Controls On Particle Settling Velocity And Bed Erodibility In The Presence Of Muddy Flocs And Pellets As Inferred By Advs, York River Estuary, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright

Presentations

.

Sediment Settling Velocity From Advs And Settling Tubes: Agreement Over A Range Of Particle Types And Hydrodynamic Conditions, G. M. Cartwright, C. T. Friedrichs, S. J. Smith

Presentations

No abstract provided.

0112+1703_Nir_Gnirs, Michael C. Liu

Publications and Research

No abstract provided.

2114-2251_Nir_Gnirs, Michael C. Liu

Publications and Research

No abstract provided.

P For Discussion: Naming Superheavy Halogen And Noble Elements, Shawn Burdette, Brett Thornton

Shawn C. Burdette

No abstract provided.

Recent Field Observations Of Mixed And Cohesive Sediment Particle Properties In Coastal And Estuarine Environments, C. T. Friedrichs

Presentations

No abstract provided.

Comparison Of Sontek Advocean-Hydras And Nortek Adv Vectors For Measuring Suspended Sediment Concentration Via Acoustic Backscatter, G. M. Cartwright, C. T. Friedrichs, R. Pico Vila, P. D. Panetta

Presentations

No abstract provided.

2012 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science

Data

Abstract: The 2012 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been …

Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within The Chesapeake Bay, A. Bever, M. Friedrichs, C. Friedrichs, M. Scully

Presentations

No abstract provided.

Collaborative Opportunities With The Physical Sciences Research Group, C. T. Friedrichs

Presentations

No abstract provided.

Rainich-Type Conditions For Null Electrovacuum Spacetimes Ii, Charles G. Torre

Research Vignettes

In this second of two worksheets I continue describing local Rainich-type conditions which are necessary and sufficient for the metric to define a null electrovacuum. In other words, these conditions, which I will call the null electrovacuum conditions, guarantee the existence of a null electromagnetic field such that the metric and electromagnetic field satisfy the Einstein-Maxwell equations. When it exists, the electromagnetic field is easily constructed from the metric. In this worksheet I consider the null electrovacuum conditions which apply when a certain null geodesic congruence determined by the metric is twisting. I shall illustrate the these conditions using a …

On Covariance Structure In Noisy, Big Data, Randy Paffenroth, Ryan Nong, Philip Du Toit

Randy C. Paffenroth

Herein we describe theory and algorithms for detecting covariance structures in large, noisy data sets. Our work uses ideas from matrix completion and robust principal component analysis to detect the presence of low-rank covariance matrices, even when the data is noisy, distorted by large corruptions, and only partially observed. In fact, the ability to handle partial observations combined with ideas from randomized algorithms for matrix decomposition enables us to produce asymptotically fast algorithms. Herein we will provide numerical demonstrations of the methods and their convergence properties. While such methods have applicability to many problems, including mathematical finance, crime analysis, and …

Pox And The City, Elizabeth S. Goins

Journal of Interactive Humanities

Pox in the City is a prototype of a social history game that focuses on the medical profession circa 1800 in Edinburgh. The prototype was research, designed and developed on a small budget (about $17,000) and in a short time frame (20 weeks). The experimental design goal was to create a narrative driven educational game that was engaging and delivered some basic educational goals to be used in the high school and college level classrooms. To experiment with writing historic game narrative and to stay within budget, the design was built around a point and click adventure framework. Narrative was …

Phanerozoic Surface History Of The Slavecraton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring

Geosciences Faculty Publications

New apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85–90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the craton. This …

Empirical Investigation Of The Factors Influencing Marine Applications Of Emi, V. A. Bell, T. D. Steinhurst, C. Friedrichs

Presentations

No abstract provided.

Peaklet Analysis: Software For Spectrum Analysis, Bruce Kessler

Mathematics Faculty Publications

This is the presentation I was invited to give at the Kentucky Innovation and Entrepreneurship Conference, regarding the software that I have developed and worked at commercializing with the help of Kentucky Science and Technology Corporation.

Hamamatsu Flash4.0 Scmos Exposure Time Series, George Mcnamara

George McNamara

Hamamatsu FLASH4.0 scientific cMOS camera exposure time series are pairs of images of:

1 millisecond (00,001ms series)

10 millisecond (00,010ms series)

100 millisecond (00,100ms series)

1,000 millisecond (01,000ms series)

4,000 millisecond (04,000ms series)

10,000 millisecond (10,000ms series)

I also included:

* difference images (exposure 2 minus exposure 1 plus 100 intensity values).

* a series of eleven 1 second (1,000 ms) exposure time images in a multi-plane TIFF file (different images than the pair of 1,000ms images above).

* Stack Arithmetic: Median, Average, Minimum, Maximum, of the eleven plane series (Stack Arithmetic is a MetaMorph command).

These images were acquired …

Gr 20 Workshop, Warsaw, July 2013, Ian M. Anderson, Charles G. Torre

Presentations

These are the Maple worksheets used at the Differential Geometry in Maple Workshop, which was held at the 20th International Conference on General Relativity and Gravitation, in Warsaw, July 2013.

There are 6 worksheets which can be downloaded from the list of files below.

Gee-2 R Data Files, Joseph Hilbe

Joseph M Hilbe

Generalized Estimating Equations, 2nd edition Publsihed: 10 December, 2012 R Data Files

Gee-2 R Scripts And Functions, Joseph Hilbe

Joseph M Hilbe

Generalized Estimating Equations, 2nd edition Published: 10 December, 2012 R scripts and functions

Gee-2 Stata Data Files, Joseph Hilbe

Joseph M Hilbe

Generalized Estimating Equations, 2nd edition Published: 10 December, 2012 Datasets

Using Tabu Search To Configure Support Vector Regression For Effort Estimation, A. Corazza, S. Di Martino, F. Ferrucci, C. Gravino, F. Sarro, E. Mendes

All Works

Recent studies have reported that Support Vector Regression (SVR) has the potential as a technique for software development effort estimation. However, its prediction accuracy is heavily influenced by the setting of parameters that needs to be done when employing it. No general guidelines are available to select these parameters, whose choice also depends on the characteristics of the dataset being used. This motivated the work described in (Corazza et al. 2010), extended herein. In order to automatically select suitable SVR parameters we proposed an approach based on the use of the meta-heuristics Tabu Search (TS). We designed TS to search …

Infrared Spectroscopy Of Symbiotic Stars. Ix. D-Type Symbiotic Novae, Kenneth H. Hinkle, Francis C. Fekel, Richard R. Joyce, Peter R. Wood

Information Systems and Engineering Management Research Publications

Time-series spectra of the near-infrared 1.6 μm region have been obtained for five of the six known D-type symbiotic novae. The spectra map the pulsation kinematics of the Mira component in the Mira–white dwarf binary system and provide the center-of-mass velocity for the Mira. No orbital motion is detected in agreement with previous estimates of orbital periods ≳100 yr and semimajor axes ∼50 AU. The 1–5 μm spectra of the Miras show line weakening during dust obscuration events. This results from scattering and continuum emission by 1000 K dust. In the heavily obscured HM Sge system the 4.6 μm CO …

Census 2000 Demographic And Housing Profile Reports, Mark Salling, Ellen Cyran, Sharon Bliss

Ellen Cyran

No abstract provided.

Rainich-Type Conditions For Null Electrovacuum Spacetimes I, Charles G. Torre

Research Vignettes

In this worksheet I describe local Rainich-type conditions on a spacetime geometry which are necessary and sufficient for the existence of a solution of the Einstein-Maxwell equations with a null electromagnetic field. When it exists, the electromagnetic field is easily constructed.