Physical Sciences and Mathematics Commons^™

Molecular Cavity Flow, Donald Greenspan

Mathematics Technical Papers

Using molecular mechanics, cavity flow is studied in a basin of 4235 water molecules at 15°C. Primary vortices are generated with wallspeeds [see pdf for notation]. The vortex motions agree with experimental results in the large. Fully turbulent flow is generated with wallspeed .V = 3000°A/ps. The mechanisms for primary vortex generation are clearly delineated, as are those for turbulent flow.

An Implementation Of The El Gamal Elliptic Curve Cryptosystem Over A Finite Field Of Characteristic P, Samuel Thomas Arslanian

Electronic Theses and Dissertations

Since the earliest times, individuals and groups of individuals have been interested in communicating sensitive information in a manner which would guarantee that such information could not be arbitrarily received. Further, such information was to be received by select recipients and this required that a means of secure information transmission be found and employed. To these ends, methods of information encryption have ever since been sought and employed. The entire study and practice of this activity, cryptology, the science of message encryption and decryption, provides a framework for this thesis. In particular, the development of cryptology has been influenced by …

Calcareous Nannofossils From The Cretaceous Of The Deep Ivorian Basin, David K. Watkins, Samir Shafik, Im Chul Shin

Department of Earth and Atmospheric Sciences: Faculty Publications

Micropaleontological investigation of four sites drilled by Ocean Drilling Program Leg 159 on the Côte d’Ivoire-Ghana Margin indicates that the initial invasion of oceanic surface waters into the Deep Ivorian Basin, as indicated by the presence of calcareous nannofossils, occurred during the late Albian. The nature of these assemblages suggests that these first Cretaceous oceanic surface waters were warm and relatively high in nutrients. These upper Albian sediments were deposited prior to significant tectonism at some of the sites, as indicated by their structurally deformed nature. The likely age of this tectonism is Cenomanian. The Upper Cretaceous consists of condensed …

Calcareous Nannofossil Paleogene Biostratigraphy Côte D'Ivoire-Ghana Marginal Ridge, Eastern Equatorial Atlantic, Samir Shafik, David K. Watkins, Im Chul Shin

Department of Earth and Atmospheric Sciences: Faculty Publications

Paleogene sections on the Côte d’Ivoire-Ghana Marginal Ridge in the eastern Atlantic Ocean, sampled at three sites during Ocean Drilling Program Leg 159, are shown to have calcareous nannofossil assemblages in distinct packages of (sub)zones separated by hiatuses or barren sediments. The packages are different at each of the sites; all fall within the interval from late Paleocene Zone CP6 to latest Oligocene Subzone CN1a inclusive. Three packages (CP9b–CP11, CP13, and CP19) on the crest of the Marginal Ridge at Site 960, four (CP7–CP9b, CP11, CP13–?CP15, and CP17–CN1a) at nearby Site 959 on the shoulder of the Marginal Ridge, and …

4. Grain-Size Distribution And Significance Of Clay And Clay-Sized Minerals In Eocene To Holocene Sediments From Sites 918 And 919 In The Irminger Basin, Kraig Heiden, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

Published by the Ocean Drilling Program, Texas A & M University, in cooperation with the National Science Foundation and Joint Oceanographic Institutions, Inc."

7. Thermal Diagenesis Of Cretaceous Sediment Recovered At The Cote D’Ivoire – Ghana Transform Margin, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

The early opening of the South Atlantic ocean along the eastern Romanche Fracture Zone, including an initial phase of transform faulting and pull-apart basin formation, followed by the generation of a seafloor spreading center, was investigated during Ocean Drilling Program Leg 159 to the Côte d’Ivoire-Ghana continental margin. Clay minerals in the <0.5-μm fraction of tectonically disturbed sediment recovered during this leg were analyzed by X-ray diffraction to determine the extent of thermal diagenesis caused by the passing of the South Atlantic spreading center along this transform margin, and to date the passing. Results from Sites 959-961 reveal mild thermal alteration of clays, to paleotemperatures of 120°–170°C, in older, mostly undated sediment, in response to an elevated paleogeothermal gradient, as indicated by the absence of randomly interstratified illite/smectite group clays (R = 0 I/S clay), and the presence of dominant regularly interstratified (R = 1) I/S clay. Thermally altered sediment at these sites underlie unaltered sediment with likely erosional contacts. Based on a date of nannofossil biozone CC9b for the oldest unaltered sediment at Site 959, the thermal event there must have been pre-CC9b.
At Site 962, drilled on a minor marginal ridge to the west of Sites 959–961, heat has altered clay in basal sediment to R = 1 I/S, and the transition uphole to thermally unaltered sediment, bearing R = 0 I/S clay, was recovered over a 175-m-thick interval, indicating …

Remote Characterization Of Wetland Vegetation And Corresponding Relationship To Soils : Final Report On The Evaluation Of Imagery-Derived Terrain Attributes In The Coastal Zone, John E. Anderson, James E. Perry, Jill Meyer

Reports

To accomplish the goals of this study, a pristine coastal barrier island environment was selected that was free from influences of urban development. This provided the optimal situation that could be expected to be encountered by military strategists and base resource managers. The site selected was Parramore Island (Figure I). Parramore Island is the seventh island ( north to south) located on the seaward margin of the southeastern Delmarva Peninsula and is one of the most dynamic and least disturbed coastal landscapes remaining in North America (McCaffrey and Dueser, 1990). The island is centered at Latitude 37° 30' and Longitude …

Rotation In Stars, Halil Kirbiyik

Turkish Journal of Physics

In this study the subject of rotation in stars and its effects have been considered. First the historical development of the subject is reviewed. After discussing the observational aspects of rotation, the effect of rotation on evolution has been investigated. The velocity of rotational meridional circulation currents and related time scales were estimated. Mixing induced by circulation currents and the turbulence which may appear as a result of such a mixing have been studied. Order of magnitude calculations have shown that rotational mixing may occur in early type stars and thus contributes to the diffusion of chemical elements. Thus, it …

The Solutions Of The Classical Relativistic Two-Body Equation, Coşkun Önem

Turkish Journal of Physics

With the relativistic Kepler problem, a two-body system is studied for positronium, the hydrogen atom and $m_2 >> m_1$ cases.

The Wind Cave National Park Elk Herd: Home Ranges, Seasonal Movements, And Alternative Control Methods, Peter Bauman

Electronic Theses and Dissertations

Elk (Cervus elaphus ne/soni) herd organization, movements, and home range size in Wind Cave National Park (WICA) were studied from May 1996 to August 1997. Twenty radiocollared elk ( 10 males, 10 females) were relocated by ground and aerial telemetry. Radiocollared elk were relocated two times/week, resulting in 1,595 relocations ( 410 ground, 1, 185 aerial). Coefficients of association (CA) for radiocollared cows averaged 0.005 during spring/summer 1996, 0.033 during spring/summer 1997, and 0.295 during falVwinter 1996. Coefficients of association for radiocollared bulls averaged 0.011 during spring/summer 1996, 0.015 during spring/summer 1997, and 0.075 during faIVwinter 1996. Three cow subherds …

Disproportionation And Structural Changes Of Tetraarylethylene Donors Upon Successive Oxidation To Cation Radicals And To Dications, Rajendra Rathore, Sergey V. Lindeman, A. S. Kumar, Jay K. Kochi

Chemistry Faculty Research and Publications

The stepwise (one-electron) chemical oxidation of the tetraphenylethylene donor and its substituted analogues (D) can be carried out by electron exchange with aromatic cations or antimony(V) oxidants to selectively afford the cation radical (D^+•) initially and then the dication (D²⁺). The ready interchange of the latter establishes the facile disproportionation (i.e., 2D^+• ⇌ D²⁺ + D) that was originally examined by only transient electrochemical techniques. The successful isolations of the crystalline salts of the tetraanisylethylene cation radical (1^+•) as well as the …

Pseudocontinuations And The Backward Shift, William T. Ross, Alexandru Aleman, Stefan Richter

Department of Math & Statistics Faculty Publications

In this paper, we will examine the backward shift operator Lf = (f −f(0))/z on certain Banach spaces of analytic functions on the open unit disk D. In particular, for a (closed) subspace M for which LM Ϲ M, we wish to determine the spectrum, the point spectrum, and the approximate point spectrum of L│M. In order to do this, we will use the concept of “pseudocontinuation" of functions across the unit circle T.

We will first discuss the backward shift on a general Banach space of analytic functions and then for the weighted …

Ionization Dynamics In Fast Ion-Atom Collisions. Ii. Final-State Momentum Distributions Of The Ionization Products In Collisions Of He With Bare Carbon Ions, Lokesh C. Tribedi, P. Richard, Y. D. Wang, C. D. Lin, Ronald E. Olson, L. Gulyas

Physics Faculty Research & Creative Works

We have used the energy and angular distributions of the low-energy electron emission cross sections from the preceding paper [Lokesh C. Tribedi et al., Phys. Rev. A 58, 3619 (1998)] to derive the doubly differential final-state longitudinal momentum distributions of the electrons, recoil ions, and projectiles in ion-atom ionization for [Formula Presented] The complementary nature of the electron spectroscopy and the recoil-ion momentum spectroscopy have been investigated using a formulation based on three-body kinematics to explore the ionization dynamics in detail. The influence of the three-body ionization as well as the binary-encounter processes on the recoil-ion (and projectile) longitudinal momentum …

Climate Change And Utah, United States Environmental Protection Agency

Elusive Documents

No abstract provided.

The Uses Of Existing Information In The Process Of Setting Social Standards For Proposed Wilderness Areas Of Zion National Park, Mark E. Vande Kamp

Elusive Documents

No abstract provided.

Climate Of Salt Lake City, Utah, William J. Alder, Laurence S. Nierenberg, Sean T. Buchanan, William Cope, James A. Cisco, Craig C. Schmidt, Alexander R. Smith, Wilbur E. Figgins

Elusive Documents

No abstract provided.

Adding Nutrients To Enhance The Growth Of Endangered Sockeye Salmon: Trophic Transfer In An Oligotrophic Lake, Phaedra E. Budy, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Snake River sockeye salmon Oncorhynchus nerka, listed under U.S. law as endangered in 1991 in response to a decline in anadromous adult numbers, spend their first 1–2 years in Redfish Lake, Idaho, before migrating to the sea. To determine how nutrient enhancement might influence phytoplankton, zooplankton, and fish production, we performed fertilization experiments in large enclosures in this oligotrophic lake using juvenile kokanee (lacustrine O. nerka) as analogues for endangered sockeye salmon. Fertilization of the metalimnion substantially increased chlorophyll a (150%), phytoplankton biovolume (75%), primary productivity (250%), and zooplankton biomass (200%), and moderately increased fish growth (12%) over our control …

The Role Of Anadromous Sockeye Salmon (Oncorhynchus Nerka) In The Nutrient Loading And Productivity Of The Sawtooth Valley Lakes, Idaho, H. P. Gross, Wayne A. Wurtsbaugh, Chris Luecke

Watershed Sciences Faculty Publications

We constructed a simulation model for Redfish Lake, Idaho, using water budget and nutrient loading measurements, to predict the dependence of lake production on nutrients from the watershed, precipitation, lake fertilization, and marine-derived nutrients from sockeye salmon Oncorhynchus nerka, which historically have reared in the lake. We also used the model to simulate different management scenarios to help restore the endangered Snake River sockeye salmon. The model and other empirical evidence indicated that even before hydropower dams were present in the migration corridor, marine-derived nutrients were not of major importance to lake production, contributing only about 3% of the annual …

A Java Implementation Of A Portable Desktop Manager, Scott J. Griswold

UNF Graduate Theses and Dissertations

Computers equipped with a Graphical User Interface (GUI) and connected to the Internet are common in both the business and educational communities. These computers, using a web browser, easily share programs written in the Java programming language that are able to execute on a variety of heterogeneous machines.

While programs written in many languages will not execute unmodified on different computing platforms because of portability restrictions, Java has overcome these limitations and provides a platform independent language. However, every programming language is limited, and no language provides all the features required for every program. Therefore, creation of any portable program …

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

All Physics Faculty Publications

No abstract provided.

A Compact Rotating-Mirror Autocorrelator Design For Femtosecond And Picosecond Laserpulses, D. Mark Riffe, A. J. Sabbah

All Physics Faculty Publications

An interferometric rapid-scanning autocorrelator employing two antiparallel rotating mirrors in a variable arm is optimized for maximum optical path difference as a function of the separation of the two rotating mirrors. A very compact design (mirror separation≈mirror diameter) is possible without a reduction in the maximum pulse width that can be measured.

Interdisciplinary Scientists Gather For Plasma Structure Workshop, Jan Josef Sojka

All Physics Faculty Publications

Two of the most exciting papers presented at the Third Peaceful Valley Workshop were on the nature of plasma structure found in the nighttime midlatitude E and F regions. The first was from a coordinated rocket campaign called Sporadic E Experiment over Kyushu (SEEK) dedicated to the understanding of puzzling quasi-periodic radar echoes that have been detected in association with sporadic E layers. In-situ probes on two rockets measured localized electric fields as large as 20 mV/m, confirming theoretical predictions of strong polarization processes that may result from wavelike distortions imposed on normally stratified sporadic E layers. An unexpected result …

Dynamical Effects Of Ionospheric Conductivity On The Formation Of Polar Cap Arcs, L. Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain

All Physics Faculty Publications

By using a magnetosphere-ionosphere (M-I) coupling model of polar cap arcs [Zhu et al., 1993], a systematic model study of the effects of ionospheric background conductivity on the formation of polar cap arcs has been conducted. The variations of the ionospheric background conductivity in the model study cover typical ionospheric conditions, including solar minimum, solar maximum, winter, and summer. The simulation results clearly indicate that the ionospheric background conductivity can dynamically affect the mesoscale features of polar cap arcs through a nonlinear M-I coupling process associated with the arcs.

Intercomparison Of Physical Models And Observations Of The Ionosphere, D. N. Anderson, M. J. Buonsanto, M. Codrescu, D. Decker, C. G. Fesen, T. J. Fuller-Rowell, B. W. Reinisch, P. G. Richards, R. G. Roble, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

Five physical models of the ionosphere were compared with each other and with data obtained at the Millstone Hill Observatory. Two of the models were self-consistent ionosphere-thermosphere models, while for the other ionospheric models the thermospheric parameters were provided by empirical inputs. The comparisons were restricted to midlatitudes and low geomagnetic activity, but four geophysical cases were considered that covered both the summer and winter solstices at solar maximum and minimum. The original motivation of the study was to determine why several physical models consistently underestimated the F region peak electron density, by up to a factor of 2, in …

Spruce Ecosystem Recovery Project Final Environmental Impact Statement, United States Forest Service

Final environmental Impact Statements (UT)

This Final Environmental Impact Statement documents the analysis of the Proposed Action, two action alternatives, and the No Action alternative developed for the Spruce Ecosystem Recovery Project (SERP) area. The Proposed Action and action alternatives considered in detail are consistent with current management direction. Each alternative responds differently to the issues associated with the Proposed Action.

Co Physisorbed On Ionic Crystals: An Extended Beg Spin-Lattice Model Of Absorbed Dipolar Molecules, T. E. Burns, John R. Dennison

All Physics Faculty Publications

The 2D dielectric phases and phase transitions of adsorbed dipolar molecules are studied using a dilute spin-one Ising model. The spin-one formulation assigns a spin S_i=±1 to a (up/down) dipole occupying a lattice site I adsorbed perpendicular to the substrate surface and S_i=0 to unoccupied sites. We relate the mean field expression for the spin-model interaction energy to a more detailed microscopic model involving dipolar, quadrupolar and repulsive interactions beyond nearest neighbor. Analytic solutions in the mean field approximation are discussed for dipole-orientation order–disorder transitions and ferroelectric-to-antiferroelectric transitions as a function of temperature and coverage. The …

Observed Coupling Of The Mesosphere Inversion Layer To The Thermal Tidal Structure, J W. Meriwether, X Gao, Vincent B. Wickwar, T D. Wilkerson, K C. Beissner, S C. Collins, M E. Hagan

All Physics Faculty Publications

Rayleigh lidar observations of mesosphere temperature profiles obtained from 40 to ∼100 km from Logan, Utah (41.7, 111.8 W, altitude, 1.9 km) over 10 nights in late February, 1995, revealed an interesting development between 60 to 75 km of a winter mesosphere inversion layer with an amplitude of ∼20–30 K and a downward phase progression of ∼1 km/hr. The data also showed two altitude regions exhibiting significant cooling of 10–30 K in extent. These were located below and above the peak of the inversion layer, respectively, at altitudes of ∼50–55 km and ∼70–80 km. When these results were compared with …

Secondary Electron Emission And Spacecraft Charging, Neal Nickles, John R. Dennison

All Physics Faculty Publications

Spacecraft charging due to the natural plasma environment found in all orbits is known to produce many of the observed spacecraft anomalies and failures. A primary factor in adverse spacecraft charging is the secondary electron emission of differing materials on the spacecraft. Precipitating electrons and ions from the plasma to spacecraft surfaces can result in varying amounts of charge being released, depending on the secondary electron yield of the materials; this can lead to arcing between surfaces. NASA's Space and Environments Effects (SEE) program has recognized the need to improve their current materials database for modeling spacecraft charging and have …

Gradient Drift Instability Growth Rates From Global-Scale Modeling Of The Polar Ionosphere, Jan Josef Sojka, M. V. Subramanium, L. Zhu, Robert W. Schunk

All Physics Faculty Publications

The winter polar ionosphere, under southward interplanetary magnetic field (IMF) conditions, experiences irregularity development leading to consequences such as scintillation on transionospheric communication links. These irregularities are associated with antisunward convecting polar ionospheric patches. The gradient drift instability (GDI) has been considered a primary candidate for the generation of these irregularities, or at least the long-wavelength energy source of the irregularity-wave cascade process. The Utah State University time-dependent ionospheric model (TDIM) enables the polar cap ionosphere and its patches to be modeled on a large scale in a time-evolving manner. Hence, at each point in space and time, the TDIM …

Rayleigh Lidar Measurements Of The Temporal Frequency And Vertical Wavenumber Spectra In The Mesosphere Over The Rocky Mountain Region, X Gao, J W. Meriwether, Vincent B. Wickwar, T D. Wilkerson, S C. Collins

All Physics Faculty Publications

Temporal and spatial spectral analysis techniques were applied to lidar data collected over a period of 18 months above the Rocky Mountain region at an altitude range from 45 to 70 km by a Rayleigh lidar system located in Logan, Utah (41.7°N, 111.8°W). Examination of the averaged temporal frequency F(ω) and vertical wavenumber F(m) spectra showed spectral slope values of −1.49 ± 0.03 and −2.3 ± 0.1, respectively. The observed slope for the overall averaged F(m) spectrum is considerably more positive than the value of −3 predicted by the linear instability theory but close to the …