Physical Sciences and Mathematics Commons^™

Oyster Reef Broodstock Enhancement In The Great Wicomico River, Virginia, Melissa Southworth

Dissertations, Theses, and Masters Projects

No abstract provided.

Wind Interaction With Buoyant Plumes On The Inner Continental Shelf, Sarah E. Rennie

Dissertations, Theses, and Masters Projects

The characteristics and effects of intrusions of estuarine outflow over the inner shelf were examined, based on hydrographic and meteorological observations obtained during the "Coastal Ocean Processes" (CoOP'94) field experiment located off the Outer Banks at Duck, North Carolina. The episodic presence of distinct low salinity water masses issuing from the Chesapeake Bay created an intermittent baroclinic coastal current along the North Carolina coast. Under low wind conditions, this current occupied the upper half of the water column within 9 km of the coast. The plume was bounded by a distinct southward-propagating front, a region offshore of high horizontal salinity …

Ecosystem Analysis Of Water Column Processes In The York River Estuary, Virginia: Historical Records, Field Studies And Modeling Analysis, Yongsik Sin

Dissertations, Theses, and Masters Projects

Analyses of EPA long-term datasets (1985--1994) combined with field studies and ecosystem model development were used to investigate phytoplankton and nutrient dynamics in the York River estuary. Analysis of the EPA dataset showed that algal blooms occurred during winter-spring followed by smaller summer blooms. Peak phytoplankton biomass during the winter-spring blooms occurred in the mid reach of the mesohaline zone whereas during the summer bloom it occurred in the tidal fresh-mesolialine transition zone. River discharge appears to be the major factor controlling the location and timing of the winter-spring blooms and the relative degree of potential nitrogen (N) and phosphorus …

A Probability Programming Language: Development And Applications, Andrew Gordon Glen

Dissertations, Theses, and Masters Projects

A probability programming language is developed and presented; applications illustrate its use. Algorithms and generalized theorems used in probability are encapsulated into a programming environment with the computer algebra system Maple to provide the applied community with automated probability capabilities. Algorithms of procedures are presented and explained, including detailed presentations on three of the most significant procedures. Applications that encompass a wide range of applied topics including goodness-of-fit testing, probabilistic modeling, central limit theorem augmentation, generation of mathematical resources, and estimation are presented.

A Search For Lepton Flavor Violation In The Neutral Kaon System, Christopher Henry Hoff

Dissertations, Theses, and Masters Projects

The conservation of separate lepton number is an ad hoc conservation principle in the Standard Model but several non-Standard Model theories allow violation of separate lepton number conservation. A very sensitive search for lepton flavor violation in the neutral kaon system, via the decay K0L→me , was undertaken by Brookhaven National Laboratory Experiment 871 (E871) during the 1995 and 1996 AGS HEP running periods. No K0L→me decays were observed and a single event sensitivity (SES) of 1.97x10-12 was achieved. This single event sensitivity corresponds to an upper limit on the branching fraction of BK0L→m e<4.53+/-0.21+/-0.46x 10-12 at a 90% confidence level.

Coherent Neutral Pion Photoproduction On The Deuteron, David G. Meekins

Dissertations, Theses, and Masters Projects

The differential scattering cross section for the process gd→dp0 was measured, as part of experiment E89-012 at Thomas Jefferson National Accelerator Facility. The experiment was performed in Hall C during the Spring of 1996 as the commissioning experiment for the Hall C cryogenic target. The High Momentum Spectrometer was used to detect the recoil deuteron and no effort was made to detect the p0 or its decay photons. The differential cross section was measured at a number of incident photon energies between 0.8 GeV and 4.0 GeV for the deuteron center-of-mass angles of 90?? and 136??. The data were found …

Wavelet-Based Digital Image Restoration, Viviana Sandor

Dissertations, Theses, and Masters Projects

Digital image restoration is a fundamental image processing problem with underlying physical motivations. A digital imaging system is unable to generate a continuum of ideal pointwise measurements of the input scene. Instead, the acquired digital image is an array of measured values. Generally, algorithms can be developed to remove a significant part of the error associated with these measure image values provided a proper model of the image acquisition system is used as the basis for the algorithm development. The continuous/discrete/continuous (C/D/C) model has proven to be a better alternative compared to the relatively incomplete image acquisition models commonly used …

The Role Of Adsorbed Oxygen In Secondary Emission From Metallic Substrates, Scott Gregory Walton

Dissertations, Theses, and Masters Projects

Low energy, ion- and photon-induced secondary electron and anion emission from metallic substrates has been investigated as a function of adsorbate coverage. Sodium positive ions (Na+), with kinetic energies up to 500 eV, and photons, with energies up to 23 eV, are utilized to initiate secondary emission. The principal adsorbate is oxygen with coverages ranging from none to a few monolayers.;For ion-induced emission, the secondary electron and negative ion absolute and relative yields from 302 stainless steel and polycrystalline tungsten (W) have been measured as a function of both impact energy and oxygen coverage. Additionally, the yields from a "technical" …

Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi

Dissertations, Theses, and Masters Projects

Blue marlin diversity was assessed at mtDNA, scnDNA, microsatellite DNA, and allozyme molecular markers. Hierarchical analysis of molecular variance (AMOVA) revealed that most genetic variation was maintained within populations, with a non-significant fraction attributable to variation among temporal replicates and between locations within oceans. In contrast, inter-ocean divergence was highly significant for a majority of loci within each marker class. Previous studies of mitochondrial DNA (mtDNA; n = 104) genetic variation within the blue marlin revealed two distinct clades of haplotypes, one of which was present only in the Atlantic (the 'Atlantic clade'), at a frequency of 40% &(F\sb{lcub}st{rcub}& = …

A Methodology For The Selection Of A Paradigm Of Reasoning Under Uncertainty In Expert System Development, Vivian Campbell

Theses: Doctorates and Masters

The aim of this thesis is to develop a methodology for the selection of a paradigm of reasoning under uncertainty for the expert system developer. This is important since practical information on how to select a paradigm of reasoning under uncertainty is not generally available. The thesis explores the role of uncertainty in an expert system and considers the process of reasoning under uncertainty. The possible sources of uncertainty are investigated and prove to be crucial to some aspects of the methodology. A variety of Uncertainty Management Techniques (UMTs) are considered, including numeric, symbolic and hybrid methods. Considerably more information …

A Comparison Of Advanced Time Series Models For Environmental Dependent Stock Recruitment Of The Western Rock Lobster, Saarah A. Farag

Theses: Doctorates and Masters

Time series models have been applied in many areas including economics, stuck recruitment and the environment. Most environmental time series involve highly correlated dependent variables, which makes it difficult to apply conventional regression analysis, Traditionally, regression analysis has been applied to the environmental dependent stock and recruitment relationships for crustacean species in Western Australian fisheries. Alternative models, such as transfer function models and state space models have the potential to provide unproved forecasts for these types of data sets. This dissertation will explore the application of regression models, transfer function models, and state space models to modelling the puerulus stage …

The Role Of Management In The Movement Towards Sustainability: Perceived Responsibilities, Challenges, And Opportunities, Martin Brueckner

Theses: Doctorates and Masters

The aim of this thesis was to explore the role of management in the movement towards ecologically sustainable development (ESD), investigating perceived responsibilities, challenges, and opportunities facing business management today. The point of departure for this study was the acknowledgement of the present paucity of references to ESD within the management literature, widespread amoral business conduct, and the dominance of economic rationalism within business science. This research provided an analytical review of ESD related literature, concentrating on the history and rise of the ESD paradigm, its ethical underpinnings, and economic implications to management practice. The paper highlighted the importance of …

Factors Contributing To Landslide Activity In The Winter Of 1995-96, Clearwater County Near Orofino, Idaho, Aaron Paul Wisher

All Master's Theses

Significant landslide activity occurred in Clearwater County, Idaho in November 1995 and February-May 1996. Mass wasting in the study area consisted of debris slides and earthflows triggered by rain-on-snow weather events. It is important to determine what factors contribute to landsliding in this area so that reliable prediction can reduce the destruction of property. Through field observation and aerial photo analysis, the factors contributing to landslides were studied. The objectives included a study of the geology, soils, aspect, slope gradient, vegetation and slope position related to each slide. Also a goal was to assess the role of land use in …

Integrable Unsteady Motion With An Application To Ocean Eddies, A. D. Kirwan Jr., Bruce L. Lipphardt

CCPO Publications

Application of the Brown-Samelson theorem, which shows that particle motion is integrable in a class of vorticity-conserving, two-dimensional incompressible hows, is extended here to a class of explicit time dependent dynamically balanced flows in multilayered systems. Particle motion for nonsteady two-dimensional flows with discontinuities in the vorticity or potential vorticity fields (modon solutions) is shown to be integrable. An example of a two-layer modon solution constrained by observations of a Gulf Stream ring system is discussed.

Parametric Software Project Estimating: An Analysis Of Current Practice, Stuart Hope

Theses: Doctorates and Masters

As society and the world economy moves into the second millennium. the service industries involving knowledge workers will continue to increase. Software is the enabling technology that is driving the knowledge industry. As the development of software is mostly a design process, where new artefacts are conceived and built, the prediction of outcomes in the process is fraught with difficulties. Software project estimating is one of the essential Software Engineering techniques that will enable the rationalisation of decision-making regarding software development. Estimates that are more accurate will increase the probability of success and lower the risk. This thesis analyses the …

Using Multimedia Microworlds To Motivate And Engage Adult Learners, Susan B. Stoney

Theses: Doctorates and Masters

As educational institutions come under increasing pressure from outside forces to restructure the way students learn, efforts are being made by researchers to find ways to assist students to learn through independent thought and to solve problems in a resource-based, self-paced environment. Such an environment needs to be sufficiently interesting and novel to motivate students who begin to use it, and to continue to engage them as they progress through it. This study has sought to identify what such a learning environment needs to encompass in order to motivate and engage adult learners so that they will not only want …

Electroproduction Of The S(11)Meson(1535) Resonance At High Momentum Transfer, Christopher Stephen Armstrong

Dissertations, Theses, and Masters Projects

The amplitude of the $S\sb{11}$(1535) resonance at values of four-momentum transfer $Q\sp2 > 0$ is not explained by the nonrelativistic constituent quark model, and is currently a topic of theoretical interest; in addition, the large branching fraction of this resonance to the proton-$\eta$ decay channel is not well understood. There is also controversy concerning the $Q\sp2$ regime in which perturbative QCD becomes important in describing nucleon resonances such as the $S\sb{11}$. The $p(e, e\sp\prime p)\eta$ reaction is an excellent system in which to study this resonance and address the issue of possible perturbative effects: the $p\eta$ channel is not accessible to …

Exploiting Cache Locality At Run-Time, Yong Yan

Dissertations, Theses, and Masters Projects

With the increasing gap between the speeds of the processor and memory system, memory access has become a major performance bottleneck in modern computer systems. Recently, Symmetric Multi-Processor (SMP) systems have emerged as a major class of high-performance platforms. Improving the memory performance of Parallel applications with dynamic memory-access patterns on Symmetric Multi-Processors (SMP) is a hard problem. The solution to this problem is critical to the successful use of the SMP systems because dynamic memory-access patterns occur in many real-world applications. This dissertation is aimed at solving this problem.;Based on a rigorous analysis of cache-locality optimization, we propose a …

Platinized Tin Oxide: A Low-Temperature Oxidation Catalyst, Erik Joshua Kielin

Dissertations, Theses, and Masters Projects

Some combinations of noble metal and reducible metal oxide possess a synergistic level of activity for the catalytic oxidation of CO at lower temperatures and partial pressures of O2 than can be obtained by either component alone. The most promising candidates, Au on MnO2 and Pt on SnO 2, were investigated for the effects on activity of noble metal loading, of reductive pretreatment at elevated temperature, and of reaction gas mixture composition. Optimum activity was obtained at a noble metal loading of 28% Au/MnO2 and 17% Pt/SnO2. Both catalysts benefitted from reductive CO pretreatment at 125??C. Both catalysts showed enhanced …

Spectroscopy Of Charge-Coupled Devices, Lars Mündermann

Dissertations and Theses

A systematic study of persistent, or residual, images occurring in CCD imagers and a systematic study of dark current generation in CCD imagers are presented. These effects are a source of unwanted signal in frames, and should be considered where very exact, low light-level signal processing is necessary. For both studies explanatory models and statistical analysis techniques have been developed which enable the derivation of the densities and the characteristic energies. Furthermore the importance of understanding these phenomena in the context of today's low light-level imaging is discussed.

Impurity sites are found to be responsible for residual images. Photoelectrons are …

The Synthesis And Characterization Of A Porphyrin Oligomer As A Potential Antenna For Light Harvesting Solar Cells, Tristan Timothy Jenkins

Dissertations and Theses

Mankind's attempts to harvest the sun have resulted in photocells with about 15% overall energy conversion efficiency. The best of these cells consist of a light-sensitive dye attached to a semiconductor. Absorbed light energy is transferred to the semiconductor via the delivery of an excited electron from the dye. Dye electrons are replenished with a redox solution, coupling the dye to the counter electrode.

This research was the beginning of an exploration into some potential improvements in the cell. First of all, the redox solution is a corrosive liquid, and leaks present a problem. A porphyrin oligomer with a TCPP …

Resource Notes-Academic Year 1997-98

Conservation and Survey Division

No abstract provided.

Resource News-Winter 1997-98

Conservation and Survey Division

No abstract provided.

Resource News-Spring 1998

Conservation and Survey Division

No abstract provided.

Nebraska Oil And Gas Production And Value For 1996 And 1997, R. R. Burchett, W. H. Sydow

Conservation and Survey Division

No abstract provided.

Earthquakes In Nebraska, R. R. Burchett

Conservation and Survey Division

No abstract provided.

Oil And Gas Fields In Nebraska, R. R. Burchett

Conservation and Survey Division

No abstract provided.

Mineral Facts For Nebraska, Excluding Oil And Gas, R. R. Burchett

Conservation and Survey Division

No abstract provided.

Oil And Gas Facts For Nebraska, R. R. Burchett

Conservation and Survey Division

No abstract provided.

Colfax County Test Hole Logs, Frank A. Smith, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.