Physical Sciences and Mathematics Commons^™

Evaluation And Application Of Space Telescope Aberration Sensing Using Phase Diversity, David J. Lee

Theses and Dissertations

Due to mechanical aspects of fabrication, launch, and operational environment, space telescope optics can suffer from unforeseen aberrations, detracting from their intended diffraction-limited performance goals. This dissertation gives the results of simulation and theoretical studies designed to explore how wavefront aberration information for such "nearly diffraction-limited" telescopes can be estimated via the Gonsalves (least-squares) phase diversity technique. In traditional phase diversity, aberrations are estimated from two images—one conventional, focused image and one image that has been defocused by a known amount. These studies are original and significant in that this effort represents the first time the effects of photon noise …

Water Current, Volume 29, No. 2, April 1997

Water Current Newsletter

State Collaboration Key to Sustaining Aquifer
From the Director: Participants Pleased with Conference; Certifying Nebraska Water Operators
Water Stewards Honored at 26th Annual Water Conference
Environmental Programs Web Site Named "Best of the Internet"
Nebraska's Natural Resources Districts Celebrating Silver Anniversary
NU-KSU Join Forces to Reduce Nonpoint Source Pollution in Blue River Basins Water News Briefs
Accessing Water on the World Wide Web

Fragment Rotational Distributions From The Dissociation Of Nebr2: Experimental And Classical Trajectory Studies, Mehdi Nejad-Sattari , '95, Thomas Alex Stephenson

Chemistry & Biochemistry Faculty Works

The Br-2 fragment rotational distributions that result from the vibrational predissociation of NeBr2 in the B electronic state have been measured for several initial vibrational levels. In each case, the rotational distributions extend to the effective energetic Limit determined by the amount of energy available (E(av1)) for disposal into the fragment rotational and translational degrees of freedom. Analysis of the data allows refinement of the NeBr2 dissociation energy; we find that D-0=70.0 +/- 1.1 cm(-1) for the X electronic state, v = 0. Both Delta v = - 1 and -2 dissociation events have been examined. For dissociation pathways with …

Review Of Possible Health Effects Of Exposure To Residential Electric And Magnetic Fields, David W. Hafemeister

Physics

No abstract provided.

Circulation, Vol. 4, No. 3, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Spring 1997 issue of CCPO Circulation featuring article "Fostering Oceanographic Collaboration in Cameroon"

Neutron-Irradiation Effects On The V-I Characteristics Of Yba2cu3o7-Δ Twinned Crystals:Linking Transport Results In A Variety Of Copper Oxide Superconductors, Brandon R. Brown

Physics and Astronomy

We have investigated the depinning process of magnetic flux vortices in twinned crystals of YBa₂Cu₃O_7-δ in intermediate applied magnetic fields parallel to the crystallographic c axis through precise resistivity measurements before and after fast-neutron irradiation. Of particular interest for each field is the power-law dependence of the electric field on current density, E∝Jⁿ, at a well defined temperature which separates a nonlinear region below from a more linear, dissipative region above. We find that n shows a striking dependence on the estimated value of the Larkin-Ovchinnikov length. The relation is not only manifest …

Isotope Ratio Studies Of Marine Mammals In Prince William Sound, Donald M. Schell, Amy Hirons

Marine & Environmental Sciences Faculty Reports

This project consists of two components: (1) provision of analytical services for the stable isotope ratio investigations associated with Exxon Valdez oil spill projects, and (2) an investigation of food web relationships and trophic interactions of harbor seals and other top consumers of Prince William Sound (PWS). Through the use of harbor seal tissues collected from native harvested animals and tagging programs, seasonal and migrational information has been obtained with regard to prey utilization and trophic status at differing locations within the sound and the adjacent Gulf of Alaska. Preliminary results indicate that within PWS, harbor seals fall at the …

Towards Granular Hydrodynamics In Two-Dimensions, E.L. Grossman, T. Zhou, E. Ben-Naim

Eli Ben-Naim

We study steady-state properties of inelastic gases in two-dimensions in the presence of an energy source. We generalize previous hydrodynamic treatments to situations where high and low density regions coexist. The theoretical predictions compare well with numerical simulations in the nearly elastic limit. It is also seen that the system can achieve a nonequilibrium steady-state with asymmetric velocity distributions, and we discuss the conditions under which such situations occur.

Acute Toxicity And Behavioral Effects Of Chlorpyrifos, Permethrin, Phenol, Strychnine, And 2,4-Dinitrophenol To 30-Day-Old Japanese Medaka (Oryzias Latipes), Steven P. Bradbury, Patricia J. Rice, Charles D. Drewes, Theresa M. Klubertanz, Joel R. Coats

Steven P. Bradbury

Five chemicals with different modes of action were evaluated in laboratory studies to determine their acute toxicity (48-h median lethal concentration [LC50]) and behavioral effects on 30-d-old Japanese medaka (Oryzias latipes). The order of toxicity for these xenobiotics was permethrin > chlorpyrifos > 2,4-dinitrophenol (2,4-DNP) > strychnine > phenol. The 48-h LC50s were significantly different and ranged from 0.011 to 24.1 mg/L. In addition, chlorpyrifos and permethrin accumulated in the tissues of juvenile O. latipes. Observations of five behavioral/morphological responses, including changes in equilibrium, general activity, startle response, and morphology (e.g., hemorrhage and deformities) were used as indicators of sublethal toxicity. Each chemical, with …

42. Kenichi Fukui, Otto Vogl, Tetsuki Yamaoka

Otto Vogl

No abstract provided.

Ichthyofaunal And Habitat Associations Of Distinct Populations Of Southern Redbelly Dace, Phoxinus Erythrogaster (Teliostei: Cyprinidae) In Mississippi, Martin O'Connell

Earth and Environmental Sciences Faculty Publications

Twenty-two field sites in W-central Mississippi were surveyed for southern red- belly dace Phoxinus erythrogaster to characterize habitat and ichthyofaunal associations of these 'endangered' disjunct populations. Phoxinus erythrogaster occurred at only six sites. Data assessed similarity among all sites and described microhabitat associations of P erythro- gaster. Five species, including Semotilus atromaculatus, Campostoma anomalum, Etheostoma whipplei, P erythrogaster and Pimephales notatus, comprised 95% of the total number of in- dividuals collected at P erythrogaster sites. Standardized abundance (number per seine haul) for S. atromaculatus was consistently high among all P erythrogaster sites, whereas standard- ized abundance for C. anomalum, P …

Santa Clara Magazine, Volume 39 Number 1, Spring 1997, Santa Clara University

Santa Clara Magazine

6 - BLUE SKY INVASION Searching for the American Dream, aerospace workers transform the Santa Clara Valley. By David Beers '79, Illustrations by Dug Waggoner

15 - SEEING IS BELIEVING Professor Sally Wood develops software to help students visualize basic engineering concepts. By Laura Trujillo '92

18 - CONFRONTING THE SCARS OF CENTURIES A legal challenge to California's Proposition 209 is the latest round in a long- running debate over affirmative action. By Margaret M. Russell

26 - SHADOWY ALLIANCE A recent expose alleging CIA links to the crack cocaine epidemic in California's inner cities raises questions about responsibility and …

The Extremely Active Single Giant 1e 1751+7046 = Et Draconis: Revised Properties And A Reevaluation Of Its Evolutionary Status, Carol W. Ambruster, Francis C. Fekel, Edward F. Guinan, Bruce J. Hrivnak

Information Systems and Engineering Management Research Publications

New spectroscopic observations have resulted in significant revisions to several of the orginally published properties of the X-ray bright, chromospherically active star 1E 1751+7046: the spectral classification has been revised from K5 IV to K0 III, v sin i from 30-40 km s-1 to 23 km s-1, and the reported nondetection of the Li I 6707 Å line to a significant log epsilon(Li) = 1.8. Chromospheric and transition region surface fluxes from IUE observations and the coronal surface flux from earlier Einstein data are close to saturation levels, and comparable only to very active binaries, pre-main-sequence stars, and FK Comae …

Water Resources Review - April 1997 Vol 10 No 1, Annis Water Resources Institute

AWRI Reviews

No abstract provided.

Network Servers For Multidisciplinary Problem Solving, Anupam Joshi, Sanjiva Weerawarana, Elias N. Houstis, John R. Rice, Shahani Markus

Department of Computer Science Technical Reports

No abstract provided.

Microscopic Nature Of Thermally Stimulated Current And Electrical Compensation In Semi-Insulating Gaas, S. Kuisma, K. Saarinen, P. Hautojarvi, Z-Q. Fang, David C. Look

Physics Faculty Publications

No abstract provided.

The Planet, 1997, Spring, Julie Irvin, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.

A Fast Scan Submillimeter Spectroscopic Technique, Douglas T. Petkie, Thomas M. Goyette, Ryan P. A. Bettens, Sergei P. Belov, Sieghard Albert, Paul Helminger, Frank C. De Lucia

Physics Faculty Publications

A new fast scan submillimeter spectroscopic technique (FASSST) has been developed which uses a voltage tunable backward wave oscillator (BWO) as a primary source of radiation, but which uses fast scan (~10⁵ Doppler limited resolution elements/s) and optical calibration methods rather than the more traditional phase or frequency lock techniques. Among its attributes are (1) absolute frequency calibration to ~1/10 of a Doppler limited gaseous absorption linewidth (<0.1 MHz, 0.000 003 cm^-1), (2) high sensitivity, and (3) the ability to measure many thousands of lines/s. Key elements which make this system possible include the excellent short term spectral purity of the …

Chemistry Of The Jovian Auroral Ionosphere, J. J. Perry, Y. H. Kim, Jane L. Fox, H. S. Porter

Physics Faculty Publications

No abstract provided.

Rates, Timing, And Cyclicity Of Holocene Eolian Activity In North-Central United States: Evidence From Varved Lake Sediments, Walter E. Dean

United States Geological Survey: Staff Publications

Most of the sediment components that accumulated in Elk Lake, northwestern Minnesota, during the Holocene are autochthonous or biogenic, delivered to the sediment-water interface on a seasonal schedule, preserved in distinct annual laminae (varves). The main allochthonous component is detrital clastic material, as measured by bulk-sediment concentrations of aluminum, sodium, potassium, titanium, and quartz, that enters the lake mostly as eolian dust. The eolian clastic influx to Elk Lake was considerably greater during the mid-Holocene (8–4 ka) than it has been for the past 4000 yr, when periods of increased eolian activity correspond to the time of the Little Ice …

Councilmanic Perceptions Of Water Policy For The Lake Gaston Water Supply Project In Virginia And North Carolina, Beverly Mcafee Hedberg

Theses and Dissertations in Urban Services - Urban Management

The purpose of this case study is to analyze the perceptions of city council members in formulating and implementing policy on the Lake Gaston Water Supply Project in Virginia and North Carolina. A comparison of the perceptions of twenty-three members of three city councils: Henderson, North Carolina; Roanoke Rapids, North Carolina; and Virginia Beach, Virginia serves as the basis for analysis. Their perceptions of the issues and how they view other actors in the intergovernmental arena, within the context of the Lake Gaston Water Supply Project.

Specifically, the research examines how city council members view (1) water-policy issues, (2) the …

On The Effect Of Traffic Self-Similarity On Network Performance, Kihong Park, Gitae Kim, Mark Crovella

Department of Computer Science Technical Reports

No abstract provided.

Faster Image Template Matching In The Sum Of The Absolute Value Of Differences Measure, Mikhail J. Atallah

Department of Computer Science Technical Reports

No abstract provided.

Computer Vulnerability Analysis: Thesis Proposal, Ivan Krsul

Department of Computer Science Technical Reports

No abstract provided.

Channel Restructuring Along Crystal Springs: Creating Salmon Habitat On A Lowland Stream, Lua Olsen

WWU Honors College Senior Projects

Crystal Springs is a small tributary of Tenmile Creek located in the lower drainage basin of the Nooksack River (Figure 1). It is 2.6 km in length and has a total relief of approximately 21 meters. A soil survey of the area suggests that prior to agricultural development, Crystal Springs existed as a swamp and was later trained into the man-made irrigation ditch which it currently occupies. Aerial photographs taken as early as June 30, 1947 reveal that the channel has undergone no significant change in morphology in the last 50 years. Recently a local landowner granted permission for the …

Nonanalytic Behavior Of The Spin Susceptibility In Clean Fermi Systems, Dietrich Belitz, Theodore R. Kirkpatrick, Thomas Vojta

Physics Faculty Research & Creative Works

The wave vector and temperature-dependent static spin susceptibility, X_s(Q, T), of clean interacting Fermi systems is considered in dimensions 1 ≤ d ≤ 3. We show that at zero temperature X_s is a nonanalytic function of |Q|, with the leading nonanalyticity being |Q|^d-1 for 1 < d < 3, and Q²ln|Q| for d = 3. For the homogeneous spin susceptibility we find a nonanalytic temperature dependence T^d-1 for 1 < d < 3. We give qualitative mode-mode coupling arguments to that effect, and corroborate these arguments by a perturbative calculation to second order in the electron-electron interaction amplitude. The implications of this, in particular for itinerant ferromagnetism, are discussed. We also point out the relation between our findings and established perturbative results for one-dimensional systems, as well as for the temperature dependence of X_s(Q = 0) in d = 3.

Investigating The Use Of Kalman Filtering Approaches For Dynamic Origin-Destination Trip Table Estimation, Pushkin Kachroo, Kaan Ozbay, Arvind Narayanan

Electrical & Computer Engineering Faculty Research

This paper studies the applicability of Kalman filtering approaches for network wide traveler origin-destination estimation from link traffic volumes. The paper evaluates the modeling assumptions of the Kalman filters and examines the implications of such assumptions.

Feedback Control Solutions To Network Level User-Equilibrium Real-Time Dynamic Traffic Assignment Problems, Pushkin Kachroo, Kaan Ozbay

Electrical & Computer Engineering Faculty Research

A new method for performing dynamic traffic assignment (DTA) is presented which is applicable in real time, since the solution is based on feedback control. This method employs the design of nonlinear H∞ feedback control systems which is robust to certain class of uncertainties in the system. The solution aims at achieving user equilibrium on alternate routes in a network setting.

Prototype Implementation Of The Comprehensive Parallel Integration Tool Parint, Jay Ball

Masters Theses

The ParInt project allows users to integrate multivariate functions using parallel computers via different methods encompassed in an easy to use interface. This thesis describes the initial version of the ParInt package. Various pop up windows of the graphical user interface, program procedures, programming paradigms, integration theory, and future considerations are all described.

Optimization Of Plasmas For Recombination-Pumped Short-Wavelength Lasers, M. Murphy, C. Glasheen, F. A. Moscatelli, Thomas D. Donnelly

All HMC Faculty Publications and Research

We report on experiments investigating the optimization of laser-ablated plasmas which are used to produce recombination-pumped, short-wavelength lasers. We evaluate the density of electrons and neutral atoms in laser ablated lithium and carbon plasmas as a function of time and distance away from the ablated target surface. We use an interferometric technique which can reveal information about the temperature of the plasma electrons. We find that the cold electrons which result in gain in recombination-pumped lithium lasers on the Lyman-α transition are produced by the high-intensity pump pulse rather than the lower intensity ablating pulse.