Physical Sciences and Mathematics Commons^™

A >130,000-Year-Long Pollen Record From Pittsburg Basin, Illinois, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

Pittsburg Basin, in south-central Illinois, contains a sediment record extending from the present back to the end of the late Illinoian glaciation, when central Illinois was covered with Picea/Pinus forest. During the last interglaciation, a temperate deciduous forest more diverse than Holocene Quercus/Carya forest replaced the Illinoian late-glacial boreal forest. Prairie pollen types and the charcoal/pollen ratio, indicating fire frequency, temporarily increased. Then forest, with high Juniperus percentages, became dominant once more, as the charcoal/pollen ratio dropped. After the last interglaciation, the charcoal/pollen ratio increased again and prairie and wetland surrounded Pittsburg Basin through the entire Wisconsinan glacial age. The …

Strain And Strain Relief In Gd(0001) Films On Mo(112), Takashi Komesu, C. Waldfried, Peter A. Dowben

Peter Dowben Publications

The electronic structure of strained and unstrained Gd(0001) has been studied with spin-polarized photoemission spectroscopy and spin-polarized inverse photoemission spectroscopy. In this work, we observed that relaxation of the expansively strained in-plane crystal lattice constant, of Gd(0001) on Mo(112), significantly diminishes the differences in the electronic structure from that observed for Gd(0001) grown on W(110). The defects that are incorporated in the Gd films, with increasing film thickness, lead to an in-plane lattice relaxation. Such thickness dependent strain relief results a loss of net polarization for Gd(0001) grown on Mo(112) compared to the relatively unstrained Gd(0001) films grown on W(110).

Applications Of Secondary Electron Energy- And Angular-Distributions To Spacecraft Charging, Neal Nickles, R. E. Davies, John R. Dennison

All Physics Faculty Publications

Secondary electron (SE) emission from spacecraft surfaces as a result of energetic electron bombardment is a key process in the electrical charging of spacecraft. It has been suggested that incorporating more complete knowledge of the energy- and angular-distributions of secondary electrons is necessary to fully model how SE emission and spacecraft charging are affected by re-adsorption of low energy electrons in the presence of charge-induced electrostatic fields and ambient magnetic fields in the spacecraft environment. We present data for such energy- and angular-distributions from sputtered, polycrystalline gold surfaces. The data are compared to empirical SE emission models and found to …

Baldur's Gate Ii - Maps & Benchmark Problems, Nathan R. Sturtevant, Bioware Corp

Moving AI Lab: 2D Maps and Benchmark Problems

Maps extracted by Yngvi Björnsson from Baldur's Gate II with explicit permission from BioWare Corp. for use and distribution as benchmark problems.

Contains 75 maps and benchmark problem sets scaled to 512 x 512 and 120 original scale maps.

Stochastic Hybrid Control, A. Bensoussan, J. L. Menaldi

Mathematics Faculty Research Publications

The objective of this paper is to study the stochastic version of a previous paper of the authors, in which hybrid control for deterministic systems was considered. The modelling is quite similar to the deterministic case. We have a system whose state is composed of a continuous part and a discrete part. They are affected by a continuous type control and an impulse control. The dynamics is moreover perturbed by noise, also a continuous and a discrete noise process. The Markovian character of the state process is preserved. We develop the model and show how the dynamic programming approach leads …

Utah State University Ground-Based Test Facility For Study Of Electronic Properties Of Spacecraft Materials, W. Y. Chang, John R. Dennison, Neal Nickles, R. E. Davies

All Physics Faculty Publications

Materials used for spacecraft and space structures in near-Earth orbit are subject to severe environmental effects including high vacuum conditions, hot and cold extremes temperature, strongly oxidizing atomic oxygen environments, and high fluxes of energetic electrons, ions, neutrals and photons. Instrumentation developed at Utah State University is designed to simulate, at least to some level, all of these conditions and to study charged particle and photon interactions with spacecraft surfaces. The facilities are particularly well suited to study electron emission as related to spacecraft charging, including secondary and backscattered yields, energy-spectra, and angleresolved measurements as a function of incident energy, …

Beneficial Use Of Dredge Material For Tampa Bay Bottom Habitat Restoration, Tampa Baywatch, Inc.

Reports

A brief description of each site is included in the text, with contact information where available. The 11 sites were selected due to their location, potential for restoration, active projects under development, public safety issues and proximity to a source of fill material. Again, the survey is intended to be a starting point. All sites will require an extensive evaluation, including opportunities for public input, before restoration plans can move forward.

The Prairie Naturalist Volume 32, No.3 September 2000

The Prairie Naturalist

SPECIAL FEATURE: LESSER PRAIRIE-CHICKEN

PREFACE ▪ C. E. Braun

NOTE ON SPECIAL FEATURES

POPULATION STATUS AND MANAGEMENT OF LESSER PRAIRIE-CHICKEN IN COLORADO ▪ K. M. Giesen

STATUS OF NESTING HABITAT FOR LESSER PRAIRIE-CHICKEN IN NEW MEXICO ▪ J. A. Bailey, J. Klingel, and C. A. Davis

STATUS OF THE LESSER PRAIRIE-CHICKEN IN NEW MEXICO, 1999 ▪ . J. A. Bailey, and S. O. Williams III

DISTRIBUTION AND POPULATION TREND OF LESSER PRAIRIE-CHICKEN IN KANSAS ▪ W. E. Jensen, D A. Robinson. Jr and R. D. Applegate

REVIEW OF THE HISTORICAL AND PRESENT STATUS OF THE LESSER PRAIRIE-CHICKEN (Tympanuchus pallidicinctus) IN …

Interactive 3-D Visualization: A Tool For Seafloor Navigation, Exploration, And Engineering, Larry A. Mayer, Mark Paton, Lindsay Gee, James V. Gardner, Colin Ware

Center for Coastal and Ocean Mapping

Recent years have seen remarkable advances in sonar technology, positioning capabilities, and computer processing power that have revolutionized the way we image the seafloor. The massive amounts of data produced by these systems present many challenges but also offer tremendous opportunities in terms of visualization and analysis. We have developed a suite of interactive 3-D visualization and exploration tools specifically designed to facilitate the interpretation and analysis of very large (10's to 100's of megabytes), complex, multi-component spatial data sets. If properly georeferenced and treated, these complex data sets can be presented in a natural and intuitive manner that allows …

The Probe, Issue 212 – September/October 2000

The Probe: Newsletter of the National Animal Damage Control Association

A Message From Our New President -- Dr. Michael Conover
An Update on AVMA's Euthanasia Guidelines -- Robert H. Schmidt,
Some residents of Colorado want to start an emergency bear feeding program. Local wildlife officials say this idea is ridiculous and would only serve to make the bears more dependent on humans.
Bureau of Alcholhol Tobacco & Firearms Halts Sales of Pyrotechnics by the Reed-Joseph International Company of Greenville Mississippi.
The North American Animal Liberation Front (ALF) took responsibility for an early morning break-in and subsequent release of lab animals at a Genesis Laboratories facility in Wellington, Colorado
NEW YORK …

A Nonlinear Parabolic Equation Modelling Surfactant Diffusion, Xinfu Chen, Chaocheng Huang, Jennifer Zhao

Mathematics and Statistics Faculty Publications

An initial-boundary value problem for nonlinear parabolic equations modelling surfactant diffusions is investigated. The boundary conditions are of nonlinear adsorptive types, and the initial value has a single point jump. We study the well-posedness of the problem, the convergence of a numerical scheme, and the regularity as well as quantitative behaviour of solutions.

Photoluminescence Measurements From The Two Polar Faces Of Zno, R. E. Sherriff, D. C. Reynolds, David C. Look, B. Jogai, J. E. Hoelscher, T. C. Collins, G. Cantwell, W. C. Harsch

Physics Faculty Publications

The crystal structure of ZnO is wurtzite and the stacking sequence of atomic layers along the “c” axis is not symmetric. As a result, a ZnO crystal surface that is normal to the c axis exposes one of two distinct polar faces, with (0001̄) being considered the O face and (0001) the Zn face. Photoluminescence (PL) measurements on the two faces reveal a striking difference. Two transitions are observed in PL that are dominant from the O face and barely observed in PL from the Zn face. These lines are identified as phonon replicas of a particular D …

Occurrence And Distribution Of Diverse Populations Of Magnetic Protists In A Chemically Stratified Coastal Salt Pond, Dennis A. Bazylinski, David R. Schlezinger, Brian H. Howes, Richard B. Frankel, Slava S. Epstein

Physics

Chemical stratification occurs in the water columns and sediments of many aquatic habitats resulting in vertical chemical and redox gradients. Various types of microorganisms are often associated with specific depths and chemical parameters in these situations. For example, magnetite-producing magnetotactic bacteria are known to form horizontal “plates” of cells at the oxic/anoxic transition zone (OATZ) of such environments. Here, we report the presence of populations of diverse magnetic protists in a seasonally chemically stratified, coastal salt pond. The protistan types included several biflagellates, a dinoflagellate, and a ciliate that were each associated with specific depths and thus, specific chemical, microbiological …

Pride Water Quality Assessment Report: I. Problems And Programs, Kentucky Water Resources Research Institute. University Of Kentucky

KWRRI Research Reports

This report provides an overview of the water quality problems and associated state and federal programs in the 40 counties that make up the PRIDE region. The 2000 Kentucky 305(b) stream assessment has identified over 1000 miles of impaired stream within the region. The major cause of pollution in the region is related to problems with pathogens. Much of these problems are related to straight pipes and failing septic and wastewater systems. It has been estimated that there are over 35,000 straight pipes and failing septic systems in the PRIDE region. A second major environmental impact in the region is …

Pride Water Quality Assessment Report: Iii. Existing And Proposed Monitoring Network, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Research Reports

This document provides a recommendation for proposed sampling sites in support of the general water quality assessment of the 40 county PRIDE region. A general assessment of the associated environmental problems and programs in the region can be found in the companion report: PRIDE Water Quality Assessment Report I: Problems and Programs while the report PRIDE Water Quality Assessment Report II: Chemical, Biological and Habitat Assessments provides a 10 year baseline assessment of environmental conditions in the region as measured by indicators of pH, fecal coliforms, habitat assessment, and macro-invertebrate assessment.

Pride Water Quality Assessment Report: Ii. Chemical, Biological And Habitat Assessments, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Research Reports

The efficient utilization of federal funds in improving the water quality and aquatic habitat of the region requires a mechanism for assessing and evaluating the impacts of the proposed and ongoing projects as well as some mechanism for prioritizing the allocation of additional funds. In order to evaluate the effectiveness of these projects it is important to provide a formal monitoring and assessment program based on sound scientific principles. This report provides an initial 10 year baseline assessment of the existing water quality conditions in the 40 county PRIDE·region for the purpose of evaluating the impacts of the PRIDE programs …

Sistem Perpustakaan Maya (Pengkhususan Kertas-Kertas Teknikal), Talib Noor Azimah

Student Works (2000-2009)

Perkembangan teknologi pada masa kini begitu pantas berlari mengikut arus peredaran zaman. Pelbagai perisian sistem yang telah dihasilkan mengikut keperluan, kehendak dan kesesuaian masa. Keadaan inilah yang telah memungkinkan pembangunan sebuah Sistem Perpustakaan Maya (SPMA) di mana ia merupakan sistem bermaklumat secara atas talian (online). SPMA merupakan sebuah sistem di atas talian yang memainkan peranan bagi membekalkan pelbagai sumber maklumat berbentuk kertas teknikal (technical paper) seperti yang dikehendaki oleh pengguna. Sistem ini dibangunkan di atas talian adalah bertujuan supaya ia boleh dicapai oleh para pengguna dari seluruh dunia. Matlamat utama sistem ini adalah bagi membantu memudahkan pengguna di dalam mencapai …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 17, Number 1, September 2000, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Torsion-Free Modules Over Reduced Witt Rings, Robert W. Fitzgerald

Articles and Preprints

We compute the genus class group of a torsion-free module over a reduced Witt ring of finite stability index. This is applied to modules locally isomorphic to odd degree extensions of formally real fields.

Distributed Development And Deployment Of Ontologies For Knowledge-Based Systems, Sameh El-Ansary

Archived Theses and Dissertations

No abstract provided.

A Structural, Magnetic, And Mössbauer Spectral Study Of Dy2fe17 And Its Hydrides, O. Isnard, Dimitri Hautot, Gary J. Long, Fernande Grandjean

Chemistry Faculty Research & Creative Works

The structural and magnetic properties of the [formula omitted] compounds, where x is 0, 1, 2, 3, and 3.8, have been investigated by means of powder x-ray diffraction, thermomagnetic and ac magnetic susceptibility measurements, and iron-57 Mössbauer spectroscopy. The Dy₂Fe₁₇H_x compounds crystallize in a hexagonal Th₂Ni₁₇ -like structure which has both an iron-rich stoichiometry and disorder of the Dy and Fe–Fe dumbbell sites. The increase in the lattice parameters, the magnetic ordering temperature, the saturation magnetization, and the dependence of the Mössbauer hyperfine parameters upon hydrogen content support a two-step filling by …

Motion-Based Video Representation For Scene Change Detection, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang, Roland T. Chin

Research Collection School Of Computing and Information Systems

We present a new ly developed scheme for automatical ly partitioning videos into scenes. A scene is general ly referred to as a group of shots taken place in the same site. In this paper, we first propose a motion annotation algorithm based on the analysis of spatiotemporal image volumes. The algorithm characterizes the motions within shots by extracting and analyzing the motion trajectories encoded in the temporal slices of image volumes. A motion-based keyframe computing and selection strategy is thus proposed to compactly represent the content of shots. With these techniques, we further present a scene change detection algorithm …

Reply To "Comment On 'Mössbauer Effect Study Of Filled Antimonide Skutterudites'", Gary J. Long, Gary J. Long, Dimitri Hautot, Fernande Grandjean, Donald T. Morelli, Gregory P. Meisner

Chemistry Faculty Research & Creative Works

The temperature dependence of the isomer shift of α-iron between 4.2 and 990 K and of Dy₃Fe₅O₁₂ between 4.2 and 550 K has been analyzed in terms of the Debye model for the second-order Doppler shift, a model in which an additional parameter, the effective vibrating mass, is included. This mass is found equal to 57 g/mol in the ionic compound, Dy₃Fe₅O₁₂, and equal to 60 g/mol in metallic α-iron. The deviation of this mass from 57 g/mol is a measure of the covalency of the metallic bonding in …

Two-Photon Detachment Cross Sections And Dynamic Polarizability Of H- Using A Variationally Stable, Coupled-Channel Hyperspherical Approach, Mauro Masili, Anthony F. Starace

Anthony F. Starace Publications

We present a generalization of the variationally stable method of Gao and Starace [B. Gao and A. F. Starace, Phys. Rev. Lett. 61, 404 (1988); Phys. Rev. A 39, 4550 (1989)] for two-electron atoms and ions that incorporates a coupled-channel adiabatic hyperspherical approach. Using this approach, we report results for two-photon detachment of H^-, in which we have coupled one, two, three, and four adiabatic hyperspherical channels within each term level of the initial, intermediate, and final states. We present results also for the dynamic polarizability of H^- as well as for the one-photon detachment cross section. …

Reversible Dissociation Of Thiolate Ligands From Molybdenum In An Enzyme Of The Dimethyl Sulfoxide Reductase Family, Robert C. Bray, Benjamin Adams, Andrew T. Smith, Brian Bennett, Susan Bailey

Physics Faculty Research and Publications

Much is unknown concerning the role of thiolate ligands of molybdenum in molybdopterin enzymes. It has been suggested that thiolate dissociation from molybdenum is part of the catalytic mechanism of bis-molybdopterin enzymes of the dimethyl sulfoxide reductase (DMSOR) family. For DMSOR from Rhodobacter capsulatus, thiolate dissociation has therefore been investigated crystallographically, by UV/visible spectroscopy, and by enzyme assays. When crystallized from sodium citrate, all four thiolates of DMSOR are within bonding distance of Mo, but after extended exposure to Na⁺-Hepes, a pair of thiolates dissociates, a mixture of structures being indicated after shorter exposures to this buffer. …

How Does Cross-Linking Effect The Thermal Stability Of Polyisoprene, Qiang Yao, Charles A. Wilkie

Chemistry Faculty Research and Publications

Polyisoprene can be cross-linked by an initial lithiation followed by reaction with both monochloro compounds and dichloro compounds. The monochloro compounds effect crosslinking through a lithium-chlorine exchange route while the use of dichloro compounds links the PIP chains with the spacer between the two chlorine atoms. A significant amount of char is produced from compounds which have been cross-linked with aromatic dihalides while aliphatic dihalides do not produce significant char.

The White Dwarf Cooling Age Of The Open Cluster Ngc 2420, Ted Von Hippel, Gerard Gilmore

Publications

We have used deep HST WFPC2 observations of two fields in NGC 2420 to produce a cluster color-magnitude diagram down to V ≈ 27. After imposing morphological selection criteria we find eight candidate white dwarfs in NGC 2420. Our completeness estimates indicate that we have found the terminus of the WD cooling sequence. We argue that the cluster distance modulus is likely to be close to 12.10 with E(B-V) = 0.04. With these parameters we find a white dwarf cooling age for NGC 2420 of 2.0 ± 0.20 (1 σ) Gyr. The 0.20 Gyr uncertainty includes errors in the photometry, …

Resummation Of Qed Perturbation Series By Sequence Transformations And The Prediction Of Perturbative Coefficients, Ulrich D. Jentschura, Jens Becher, Ernst Joachim Weniger, Gerhard Soff

Physics Faculty Research & Creative Works

We propose a method for the resummation of divergent perturbative expansions in quantum electrodynamics and related field theories. The method is based on a nonlinear sequence transformation and uses as input data only the numerical values of a finite number of perturbative coefficients. The results obtained in this way are for alternating series superior to those obtained using Padé approximants. The nonlinear sequence transformation fulfills an accuracy-through-order relation and can be used to predict perturbative coefficients. In many cases, these predictions are closer to available analytic results than predictions obtained using the Padé method.

Concept Of Local Polaritons And Optical Properties Of Mixed Polar Crystals, Lev I. Deych, Alexey Yamilov, Alexander A. Lisyansky

Physics Faculty Research & Creative Works

The concept of local polaritons is used to describe the optical properties of mixed crystals in the frequency region of their restrahlen band. It is shown that this concept allows for a physically transparent explanation of the presence of weak features in the spectra of so-called one-mode crystals and for one-two mode behavior. The previous models Were able to explain these features only with the use of many fitting parameters. We show that under certain Conditions new impurity-induced polariton modes may arise within the restrahlen of the host crystals, and study their dispersion laws and density of states. Particularly, we …

Short-Pulse Laser-Induced Stabilization Of Autoionizing States, Heider N. Ereifej, J. Greg Story

Physics Faculty Research & Creative Works

Atoms in doubly excited states above the first ionization limit can decay via autoionization in which an electron is emitted leaving an ion, or by photoemission which leaves the atom in a singly excited state. In this paper, it is demonstrated that interaction between the atoms and a laser pulse that is short compared to the autoionization lifetime can lead to large enhancement of the photoemission process by stimulating the atoms to emit a photon. Since the resultant singly excited atoms do not autoionize, this process can be viewed as an enhancement of the stabilization of the doubly excited atoms …