Physical Sciences and Mathematics Commons^™

Ionization Of Aligned Rydberg Atoms By Ion Impact, K. R. Cornelius, J. Wang, Ronald E. Olson

Physics Faculty Research & Creative Works

The classical trajectory Monte Carlo method has been used to calculate capture and ionization cross sections and final-state electron momentum distributions in H+ + H(n = 25) collisions to show how the collision mechanisms evolve over the range of intermediate projectile speeds v* = vp/ve = 1.0-5.0. A circular Rydberg target was aligned in two orientations defined by the orbital angular momentum vector of the electron being either antiparallel or perpendicular to the incident momentum vector of the projectile. Aligning the target atom in this manner helps us to single out specific collision processes otherwise obscured in a randomly oriented …

Half-Cycle Pulse Assisted Electron-Ion Recombination, Thomas J. Bensky, M. B. Campbell, Robert R. Jones

Physics

Unipolar “half-cycle” electric field pulses (HCPs) have been used to recombine free electrons and calcium ions. The field assisted process is very similar to controlled three-body recombination in plasmas. We report on experiments that utilize HCP assisted recombination to probe the probability distribution of continuum electron wave packets and produce bound wave packets that are highly localized in three spatial dimensions.

Temperature Fluctuations In Photoionized Nebulae. Ii. The Effect Of Inhomogeneous Abundances, J. B. Kingdon, Gary J. Ferland

Physics and Astronomy Faculty Publications

Recent abundance determinations based on recombination lines in several emission-line nebulae yield ionic abundances several times larger than those derived from forbidden lines. These results cast uncertainty over all abundance determinations in such objects. One possible explanation for these discrepancies frequently cited in the literature is the presence of chemical inhomogeneities. We have run a series of photoionization models to examine what effect such inhomogeneities will have on the resulting temperature structure of nebulae. We then derive abundances from these models, utilizing Peimbert's t² formalism. Our results suggest that, although chemical inhomogeneities may produce nonnegligible biases in abundance determinations …

Time Series Energy Production In Smoothed Particle Hydrodynamics Accretion Disks: Superhumps In The Am Canum Venaticorum Stars, James C. Simpson, Matt A. Wood

Aerospace, Physics, and Space Science Faculty Publications

The energy production time series of our purely hydrodynamic accretion disk simulations display remarkable similarities with the observed light curves of dwarf novae superhumps in general and the AM CVn stars in particular. The superhump period excess as a function of mass ratio agrees well with earlier theoretical and numerical results, and the amplitudes and relative phases of the harmonics in the power spectra agree well with the observations. The morphology of the mean pulse profile appears to be a useful predictor of system mass ratio. Our modified smoothed particle hydrodynamics code time symmetrizes the interparticle forces when individual time …

Measurement Of Elastic Υ Photoproduction At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The photoproduction reaction γp → μ+ μ-p has been studied in ep interactions using the ZEUS detector at HERA. The data sample corresponds to an integrated luminosity of 43.2pb-1. The Υ meson has been observed in photoproduction for the first time. The sum of the products of the elastic Υ(1S), Υ(2S),Υ(3S) photoproduction cross sections with their respective branching ratios is determined to be 13.3 ± 6.0(stat.)-2.3+2.7(syst.) pb at a mean photon-proton centre of mass energy of 120 GeV. The cross section is above the prediction of a perturbative QCD model. © 1998 Elsevier Science B.V. All rights reserved.

Evaluation Of The Macrocyclic Antibiotic Avoparcin As A New Chiral Selector For Hplc, K. Helen Ekborg-Ott, John P. Kullman, Xiande Wang, Kyung Gahm, Lingfeng He, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

Avoparcin is a macrocyclic glycopeptide antibiotic structurally related to vancomycin, teicoplanin, and ristocetin A. When attached to 5-μm spherical silica gel, the avoparcin proved to be an effective chiral stationary phase (CSP) that could be used in the reversed-phase, normal- phase, and polar-organic modes. The avoparcin CSP was complimentary to the other macrocyclic glycopeptide CSPs in that it could resolve some racemates that the others could not, and vice versa. Some important compounds resolved on the avoparcin CSP include verapamil, thyroxine, mephenytoin, and 2- imidazolidone-4-carboxylic acid. The use of this CSP and the optimization of separations on it are discussed. …

Utility Driven Mobile-Agent Scheduling, Jonathan Bredin, David Kotz, Daniela Rus

Computer Science Technical Reports

Mobile agents are programs capable of migrating from one host machine to another. We propose that mobile agents purchase resource access rights from host machines thereby establishing a market for computational resources and giving agents a metric to evenly distribute themselves throughout the network. Market participation requires quantitative information about resource consumption to define demand and calculate utility. We create a formal utility model to derive user-demand functions, allowing agents to efficiently plan expenditure and deal with price fluctuations. By quantifying demand and utility, resource owners can precisely set a value for a good. We simulate our model in a …

Assessing The Accuracy Of A New Diagnostic Test When A Gold Standard Does Not Exist, Todd A. Alonzo, Margaret S. Pepe

UW Biostatistics Working Paper Series

Often the accuracy of a new diagnostic test must be assessed when a perfect gold standard does not exist. Use of an imperfect test biases the accuracy estimates of the new test. This paper reviews existing approaches to this problem including discrepant resolution and latent class analysis. Deficiencies with these approaches are identified. A new approach is proposed that combines the results of several imperfect reference tests to define a better reference standard. We call this the composite reference standard (CRS). Using the CRS, accuracy can be assessed using multistage sampling designs. Maximum likelihood estimates of accuracy and expressions for …

Cusp Energetic Ions: A Bow Shock Source, S. W. Chang, J. D. Scudder, S. A. Fuselier, J. F. Fennell, K. J. Trattner, J. S. Pickett, Harlan E. Spence, J. D. Menietti, W. K. Peterson, R. P. Lepping, R. Friedel

Physics & Astronomy

Recent interpretations of cusp energetic ions observed by the POLAR spacecraft have suggested a new energization process in the cusp [Chen et al., 1997; 1998]. Simultaneous enhancement of H⁺, He⁺², and O^>+2 fluxes indicates that they are of solar wind origin. In the present study, we examine H⁺ and He⁺² energy spectra from 20 eV to several 100 keV measured by the Hydra, Toroidal Imaging Mass-Angle Spectrograph (TIMAS), and Charge and Mass Magnetospheric Ion Composition Experiment (CAMMICE) on POLAR. The combined spectrum for each species is shown to be continuous with a …

Finding Cyclic Redundancy Check Polynomials For Multilevel Systems, James A. Davis, Miranda Mowbray, Simon Crouch

Department of Math & Statistics Faculty Publications

This letter describes a technique for finding cyclic redundancy check polynomials for systems for transmission over symmetric channels which encode information in multiple voltage levels, so that the resulting redundancy check gives good error protection and is efficient to implement. The codes which we construct have a Hamming distance of 3 or 4. We discuss a way to reduce burst error in parallel transmissions and some tricks for efficient implementation of the shift register for these polynomials. We illustrate our techniques by discussing a particular example where the number of levels is 9, but they are applicable in general.

Antelope County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 2, Sue Olafsen Lackey, Frank A. Smith, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

In 1930, the Conservation and Survey Division of the University of Nebraska and the United States Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in the county under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.

The map in this report shows the location of all test holes drilled in the county since 1930.

Present techniques of …

Storm And Base Flow Water Quality For Bear, Calf And Tomahawk Creeks, Kenneth F. Steele, David N. Mott

Arkansas Water Resources Center Technical Reports

Appendices for MSC 255

The Probe, Issue 193 – October 1998

The Probe: Newsletter of the National Animal Damage Control Association

Recollections, 1966-1996 -- James E. Forbes, Past President, NADCA
Giles Resigns as NADCA President
Executive Committee to Appoint President
Call for Papers: 14th Great Plains Wildlife Damage Control Conference; Theme: "Solving Conflicts between People and Exotic Wildlife"
Book Reviews: 'The Humane Approach to Living with Wildlife", Edited by John Hadidian, Guy Hodge, and John W. Grandy, Humane Society of the United States. Fulcrum Press, 1997. 255 pags with indices. $16.95 Softcover.
Review by Stephen Vantassel, NWCO Correspondent
Review by Gregory A. Giusti, Forest & Wildlands Advisor, Cooperative Extension, University of California

Student Fact Book, Fall 1998, Twenty Second Annual Edition, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1998.

Storm And Base Flow Water Quality For Bear, Calf, And Tomahawk Creeks, Kenneth F. Steele, David N. Mott

Arkansas Water Resources Center Technical Reports

Because of the conversion of 92,780 acres of forest to pasture land in the Buffalo River watershed over a 27 year period, there is concern about the affect of agricultural activities on the water quality of the river. Three tributaries (Bear, Calf and Tomahawk creeks) located about mid-length of the Buffalo River were chosen to investigate the affect of agricultural activity on water quality because these streams provide the greatest amounts of fecal bacteria, nitrate+nitrite and phosphorus to the river, despite comprising only 13% of the watershed.

Common Conservation Works Used In Western Australia, M G. Keen

Resource management technical reports

This booklet is presented to assist proponents and planners of conservation works by describing the common types used in Western Australia. For each common type, design criteria are listed along with the variables affecting increased risks associated with degradation or structural failure. This information will be useful in choosing appropriate conservation works to alleviate specific degradation in a safe manner.

Ua66/8/3 Geogram, Wku Geography & Geology

WKU Administration Documents

Newsletter created by and about the WKU Geography & Geology highlighting activities of faculty, students and alumni.

Rank One And Loosely Bernoulli Actions In Zᵈ, Aimee S.A. Johnson, A. A. Şahin

Mathematics & Statistics Faculty Works

We define rank one for Zᵈ actions and show that those rank one actions with a certain tower shape are loosely Bernoulli for d greater than or equal to 1. We also construct a zero entropy Z² loosely Bernoulli action with a zero entropy, ergodic, non-loosely Bernoulli one-dimensional subaction.

Announcements: October 1998

Drought Network News (1994–2001)

Contents:

IUGG–99 XXII General Assembly - Inter-Association Symposium on Geophysical Hazards: Risk Assessment, Mitigation and Warning Systems

1999 National Disaster Medical System Conference

International Conference on Integrated Drought Management—Lessons for Sub-Saharan Africa

4th International Congress on Energy, Environment and Technological Innovation

Comparative Hydrometeorology Of Temperate And Semiarid Environments In India, Badrul Hasan

Drought Network News (1994–2001)

Out of a total cropped area of 178 m ha, India has 59 m ha of irrigated cropland. The remaining 119 m ha is rainfed. Crop production under rainfed conditions either occurs during the rainy season or depends on conserved or residual soil moisture. In temperate countries, the economy largely depends on production of goods and services that are less affected by the variabilities of weather. Although India receives adequate amounts of rainfall annually through the four different types of weather phenomena—southwest monsoon (74%), northeast monsoon (3%), pre-monsoon (13%), and post-monsoon (10%)—the distribution in time and space is erratic, resulting …

Persian Gulf Sea Surface Temperature As A Drought Diagnostic For Southern Iran, M. Jafar Nasemosadat

Drought Network News (1994–2001)

The Persian Gulf and Oman Sea, situated over the northwestern extremity of the tropical Indian Ocean, make up the southern border of Iran (Figure 1). During hot seasons, the sea surface temperatures (SSTs) of these water bodies are high, and a huge thermal trough system is usually dominant over the region (Bitan and Sa’aroni, 1992). The summer SSTs of the Persian Gulf are reported to be the highest in the world (Gabler, 1977).

About 30% of the total rain-bearing air masses coming to the country originate in north Africa, the Red Sea, and western Saudi Arabia (Khalili, 1992). These air …

Droughts In Tamil Nadu: A Qualitative And Quantitative Appraisal, K. K. Nathan

Drought Network News (1994–2001)

Tamil Nadu experiences recurrent droughts. Tamil literature also indicates that famine-like conditions prevailed during the Pandiyan Kingdom for nearly 12 years. The state normally benefits from northeast monsoon rainfall from October to December, unlike other regions of India, which are dominated by southwest monsoon rainfall.

In general, four major parameters determine the nature and extent of drought conditions in Tamil Nadu: (1) rainfall, (2) ground water, (3) reservoir levels, and (4) crop conditions. It is estimated that nearly 50% of the districts in the state are drought-prone. The state receives nearly 80% of its annual rainfall during the northeast monsoon, …

From The Director: October 1998, Donald A. Wilhite

Drought Network News (1994–2001)

On July 16, 1998, President Clinton signed the National Drought Policy Act into law. This law creates the National Drought Policy Commission (NDPC), which will examine current laws and programs and make recommendations to the president and Congress on the needs for a national drought policy. The Farm Service Agency of the U.S. Department of Agriculture will serve as the chair for the Commission, which will comprise 16 members. In addition to the Secretary of Agriculture, other members of the Commission will include the Secretary of the Interior, Secretary of the Army, Secretary of Commerce, Director of the Federal Emergency …

Water Resources Review - October 1998 Vol 11 No 2, Annis Water Resources Institute

AWRI Reviews

No abstract provided.

Internet For Everyone: By Alexis Leon And Matthews Leon, Vikas Publishing House, 1997., S Sadagopan

IIMB Management Review

No abstract provided.

Best Practices For Tourism Center Development Along The Red Sea Coast, Stephen M. Reeve, Stephen C. Jameson, Ragaei S. Abdel-Fattah, Bernhard Riegl, Randa Hassan, Alvin P. Newman

Marine & Environmental Sciences Faculty Reports

The spectacular coastlines along Egypt's Red Sea and Gulf of Aqaba are the focus for one of the fastest growing tourism economies in the world. In order to accomplish national objectives for growth in permanent, well-paying jobs and in foreign exchange earnings, the Tourism Development Authority (TDA) has launched an initiative to make land available to investors for resort development along these coastlines. As of December, 1997, 6,000 hotel rooms are under construction in the Red Sea region and the TDA has proposals for at least 240 major resorts to be built by the year 2020.

While this program has …

Magnetic Control Of Convection In Nonconducting Diamagnetic Fluids, J. Huang, D. D. Gray, Boyd F. Edwards

All Physics Faculty Publications

Inhomogeneous magnetic fields exert a body force on electrically nonconducting, diamagnetic fluids. This force can be used to compensate for gravity and to control convection. The field effect on convection is represented by a dimensionless vector parameter R_m=(μ₀αχ₀d³ΔT/ρ₀νD_T)(H⋅∇H)_r=0^ext, which measures the relative strength of the induced magnetic buoyancy force due to the applied field gradient. The vertical component of this parameter competes with the gravitational buoyancy effect and a critical relationship between this component and the Rayleigh number is identified for the onset of convection. …

1998 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti

Qed On A Circle, James E. Hetrick, Y. Hosotani

All Faculty Articles - School of Engineering and Computer Science

QED with massless fermions on a circle is exactly solved. The nonintegrable phase [see file], which is a dynamical degree of freedom on a circle, couples through the anomaly to the zero mode of the fermion-antifermion bound states, leading to the θ vacuum.

Abstractions For Simplifying Planning In Self-Reconfigurable Robotic Systems, Craig Mcgray, Daniela Rus

Computer Science Technical Reports

In [KVRM], we described a three-dimensional self-reconfiguring robot module called the Molecule Robot. In this paper, we provide a system of abstractions for modules in self-reconfigurable robotic systems, and show how this system can be used to simplify the motion planning of the Molecule Robot system.