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2000

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Full-Text Articles in Physical Sciences and Mathematics

An Evaluation Of Stream Flow Characteristics And Fecal Coliform Loads In Sayler's Creek Watershed, South Central Virginia, David Straton Gilbert Dec 2000

An Evaluation Of Stream Flow Characteristics And Fecal Coliform Loads In Sayler's Creek Watershed, South Central Virginia, David Straton Gilbert

Theses & Honors Papers

The Sayler's Creek watershed is located within Prince Edward County, Nottoway, and Amelia Counties of the south central region of Virginia. The Sayler's Creek Watershed consists of two small creeks: Big Sayler's Creek and Little Sayler's Creek. The Environmental Protection Agency has Big Sayler's Creek listed as impaired and not Little Sayler's Creek. Based upon visual inspections of the Sayler's Creek watershed throughout the year, Little Sayler's Creek is inlpaired for fecal coliform instead of Big Sayler's Creek. Another hypothesis of this study is that fecal coliform levels are directly related to runoff from cattle ranches in the immediate floodplain …


Fractional Derivatives, John M. Beach Dec 2000

Fractional Derivatives, John M. Beach

Theses and Dissertations

In this thesis, the reader will not find a study of any kind; there is no methodology, questionnaire, interview, test, or data analysis. This thesis is simply a research paper on fractional derivatives, a topic that I have found to be fascinating. The reader should be delighted by a short history of the topic in Chapter 1, where he/she will read about the contributions made by some of the great mathematicians from the last three centuries.

In Chapter 2 the reader will find an intuitive approach for finding the general fractional derivative for functions such as eax, x …


Instrument Performance Enhancement And Modification Through An Extended Instrument Paradigm, Stephen L. Mahan Dec 2000

Instrument Performance Enhancement And Modification Through An Extended Instrument Paradigm, Stephen L. Mahan

Doctoral Dissertations

An extended instrument paradigm is proposed, developed and shown in various applications. The CBM (Chin, Blass, Mahan) method is an extension to the linear systems model of observing systems. In the most obvious and practical application of image enhancement of an instrument characterized by a time-invariant instrumental response function, CBM can be used to enhance images or spectra through a simple convolution application of the CBM filter for a resolution improvement of as much as a factor of two. The CBM method can be used in many applications. We discuss several within this work including imaging through turbulent atmospheres, or …


Questing For The Grail: Core Collapse Supernova Simulations With Boltzmann Neutrino Transport, Otis Earl Messer Dec 2000

Questing For The Grail: Core Collapse Supernova Simulations With Boltzmann Neutrino Transport, Otis Earl Messer

Doctoral Dissertations

The importance of exact neutrino transport in spherically symmetric core collapse supernova simulations is explored in this dissertation. The primary tool for these studies is the neutrino radiation hydrodynamics code AGILE-BOLTZTRAN (Mezzacappa & Bruenn 1993a,b,c; Mezzacappa & Messer 1998; Liebendörfer 2000). AGILE-BOLTZTRAN couples the solution of the Boltzmann equation for all three flavors of neutrinos and antineutrinos to a one-dimensional, implicit, adaptive grid hydrodynamics code. Emission, absorption, and scattering of neutrinos from nucleons and nuclei, neutrino-electron scattering, and pair production and annihilation are included as neutrino-matter couplings. Details of the code are described, including the equations solved and their finite …


Electronic Excitations In Metals And Semiconductors: Ab Initio Studies Of Realistic Many-Particle Systems, Wei Ku Dec 2000

Electronic Excitations In Metals And Semiconductors: Ab Initio Studies Of Realistic Many-Particle Systems, Wei Ku

Doctoral Dissertations

Electronic excitations in metals and semiconductors, measured through inelastic x-ray scattering, electronic energy-loss spectroscopy, and angle-resolved photoemission, provide valuable information about the intrinsic many-body interactions between electrons in the crystal environment. These dynamical interactions are usually analyzed with intuitive simple models. With the problems studied, which correspond to linear response and quasi-particle excitation, it will be shown that ab initio approaches not only can provide more realistic understanding of microscopic processes and mechanisms, but also result in new theoretical interpretations that resolve a number of remarkable "anomalies." Specifically, these problems include the dispersion of the plasmon lifetime in potassium, the …


Searches For Neutral Higgs Bosons In Quark-Antiquark Tau-Antitau Final States Using The Opal Detector At Lep, James Andrew Hocker '91 Dec 2000

Searches For Neutral Higgs Bosons In Quark-Antiquark Tau-Antitau Final States Using The Opal Detector At Lep, James Andrew Hocker '91

Doctoral Dissertations

Searches for neutral Higgs bosons have been performed with the OPAL detector at LEP. Approximately 170 /pb of e+e- collision data at a center-of-mass energy of 189 GeV have been used to search for the SM process e+e- to HZ as well as for the processes e+e- to hZ and e+e- to hA which occur in extended Higgs theories. The searches are sensitive to final states containing quarks and tau leptons, for which an artificial neural network for the identification of tau leptons was designed. The results have been combined with OPAL searches for other final states to obtain a …


Allosteric Tuning Of Ruthenium 2,2’-Bipyridyl Luminescent Sensor Systems, Daqing Gan Dec 2000

Allosteric Tuning Of Ruthenium 2,2’-Bipyridyl Luminescent Sensor Systems, Daqing Gan

Masters Theses

A series of new ruthenium bipyridyl crown supramolecular sensor systems containing two binding sites were synthesized. The crystal structure and photophysical properties of the developed sensor systems were thoroughly studied using x-ray, nuclear magnetic resonance and photoscopy methods. It turned out that the chelation of transition metal on the remote sites of the bipyridyl crown ligands greatly reduced the reactivity of the crown cavity. It is believed that the chelation of transition metal on the nitrogen atoms forces the bipyridyl function towards coplanarity and restricts the conformational freedom of the crown ring. The conformational rigidity in turn influences the binding …


The Effects Of Radiation Damage On The Vortex Dynamics Of High Temperature Superconductors, Andra Petrean Dec 2000

The Effects Of Radiation Damage On The Vortex Dynamics Of High Temperature Superconductors, Andra Petrean

Dissertations

This work focuses on the interaction between magnetic vortices in high temperature superconductors and defects introduced by irradiation with protons and heavy ions. The study concentrates on the high temperature superconductor YBa;Cu30 7J5. This material is used to investigate the role of disorder in phase transitions, a topic of great interest in Solid State Physics. In addition, this study analyzes the interaction between vortices and columnar defects in various doses and defect morphologies, including the thermal stability of columnar defects.

We present experimental evidence of the vortex glass phase in proton irradiated Y B a:Cu:!0 -.15. For the first time, …


Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel Dec 2000

Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel

Masters Theses

Backstripping analysis of detailed stratigraphic data from the Bass River and Ancora boreholes on the New Jersey Coastal Plain (Ocean Drilling Project Leg 17 4AX) was conducted to test and refine previous eustatic estimates (Kominz et al., 1998) and provide new Upper Cretaceous estimates. Porositydepth relationships required by the backstripping method were estimated to supplement those from the Cost B-2 well (Rhodehamel, 1977). Sand and mud porosity at shallow depths (<500 m) obtained here are higher than was seen at the Cost B-2 well.

The Bass River and Ancora boreholes targeted older sequences of the Upper Cretaceous to Paleocene. This new data allow for more accurate estimate of the magnitude of long-term sea-level …


Development Of Realistic Simulations Of The Interactions Between Stars And The Interstellar Medium In Disk Galaxies, Thomas M. Zeltwanger Dec 2000

Development Of Realistic Simulations Of The Interactions Between Stars And The Interstellar Medium In Disk Galaxies, Thomas M. Zeltwanger

Electronic Theses and Dissertations

fWe have developed GALAXY, a two dimensional, self-consistent N-body plus hydro-dynamic computer program to model and study the behavior of disk galaxies like our Milky Way. Our goal is to better understand how such galaxies maintain their spiral structure for billions of years.

The program utilizes two independent gravitating N-body components. One simulates the collision-less star particles in the galaxy, and the other simulates colliding clouds. A gravitating hydrodynamic code simulates the interstellar medium. Additionally, a static spherical halo and a central black hole interact gravitationally with the other components of the model galaxy. All components interact with each other …


Redox Studies On The Anti-Rheumatoid Arthritis Gold Drugs: Auranofin And Solganol, Ahmed A. Mohamed Dec 2000

Redox Studies On The Anti-Rheumatoid Arthritis Gold Drugs: Auranofin And Solganol, Ahmed A. Mohamed

Electronic Theses and Dissertations

The oxidative behavior of Auranofin, 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranosato-S(triethylphosphine)gold(I), was investigated by using cyclic voltammetry (CV) in 0.1 M Bu4NBF4/CH2Cl2 and 0.1 M Bu4NPF6/CH2Cl2 solutions using Pt working and auxiliary electrodes and a Ag/AgCl reference. CV studies at scan rates from 50-2,000mVs-1 and Auranofin concentrations between 1 and 4mM, show two irreversible oxidation processes occurring at +1.1 V and +1.6 V vs. Ag/AgCl. Treatment of Auranofrn with the one electron oxidizing agent [Cp2Fe]PF6 gave a μ-thiolato digold cluster, [(Et3PAu)2(μ-SR)]22+ …


Computer-Based Methods For Constructing Two-Level Fractional-Factorial Experimental Designs With A Requirement Set, Steven L. Forsythe Dec 2000

Computer-Based Methods For Constructing Two-Level Fractional-Factorial Experimental Designs With A Requirement Set, Steven L. Forsythe

Theses and Dissertations

This dissertation developed four methodologies for computer-aided experimental design of two-level fractional factorial designs with requirement sets (DOE/RS). The requirement sets identify all the experimental factors and the appropriate interaction terms to be evaluated in the experiment. Taguchi graphs and similar manual methods provide techniques for solving the DOE/RS problem. Unfortunately, these methods are limited because they become difficult to use as the number of factors or interaction terms exceeds ten. This research showed that the DOE/RS problem belongs to a class of difficult-to-solve problems known as NP-Complete. It is the combinatorial nature of NP-Complete problems that causes them to …


Dendritic Polymers As Bonded Stationary Phases In Capillary Electrochromatography, Chiayu Helen Chao Dec 2000

Dendritic Polymers As Bonded Stationary Phases In Capillary Electrochromatography, Chiayu Helen Chao

Seton Hall University Dissertations and Theses (ETDs)

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Stability And Largeness Of The Core Of Cooperative Games., Amit K. Biswas Dr. Nov 2000

Stability And Largeness Of The Core Of Cooperative Games., Amit K. Biswas Dr.

Doctoral Theses

This monograph deals with the area from game theory known as co operativo games. Except the last chapter on NTU games, it deals with transferable utility games. llere we will introiduce and diseus the involved game theuretie notions and set a mathematical hase for the chapters to come.In 1944 von Neamann and Morgenstern(15) introduced a theory of solutions for n-person games in characteristic function form in which cooperation and coalition formation is a crucial aspect. The primary mathematical concern regarding this model is the existence of solutions or stable set. In 1968 Lucas|19 described a tem person game which has …


Information Retrieval And Mining In High Dimensional Databases, Xiong Wang Oct 2000

Information Retrieval And Mining In High Dimensional Databases, Xiong Wang

Dissertations

This dissertation is composed of two parts. In the first part, we present a framework for finding information (more precisely, active patterns) in three dimensional (3D) graphs. Each node in a graph is an undecoraposable or atomic unit and has a label. Edges are links between the atomic units. Patterns are rigid substructures that may occur in a graph after allowing for an arbitrary number of whole-structure rotations and translations as well as a small number (specified by the user) of edit operations in the patterns or in the graph. (When a pattern appears in a graph only after the …


Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise Oct 2000

Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise

Chemistry & Biochemistry Theses & Dissertations

As early as 1950, Raman spectroscopy was proposed as a method to determine aromatics and olefins in hydrocarbon mixtures. Until recently, extensive use of Raman spectroscopy in the characterization of hydrocarbons has not been practical due to several limitations. One early limitation to Raman analysis was the absence of a high intensity and stable excitation source. This problem has been overcome with the advent of lasers. Another limitation was the presence of fluorescence in hydrocarbon fuels when excited by visible lasers. However, the development of Fourier-transform Raman spectrometers now allows Raman spectra to be collected using near-IR lasers (e.g …


Copper Complexation And Speciation In The Western South And Equatorial Atlantic Ocean, John A. Consolvo Oct 2000

Copper Complexation And Speciation In The Western South And Equatorial Atlantic Ocean, John A. Consolvo

Chemistry & Biochemistry Theses & Dissertations

Presented here are the first data on copper complexation and speciation in the South Atlantic Ocean. Samples were collected at six vertical profile stations and along the surface (1m) transect during the 1996 IOC Baseline Contaminant Survey. Copper complexation measurements were made for the surface transect (1m) samples and three of the six vertical profile stations (1m - ~500m) using differential pulse anodic stripping voltammetry (DPASV) with a thin mercury film, rotating glassy carbon disk electrode (TMFRGCDE).

A strong organic copper complexing ligand (L1; log K' cuL1/cu2+ > 11. 8 ± 0 .4) was detected in 57% of all …


On Logistic And Some New Discrimination Rules:Charecterizations,Inference And Application., Supratik Roy Dr. Sep 2000

On Logistic And Some New Discrimination Rules:Charecterizations,Inference And Application., Supratik Roy Dr.

Doctoral Theses

Introduction and Summary Consider the problem of classification of an observation into one of two specified populations. Fisher's classification rale, just as several other rules commonly used in practice, depends only on the ratio of the individual densities fi(x), i = 1,2. This led Cox (1966),/27) to model the "posterior odds" by a simple function. Specifically,Cox's logistic discrimination (LGD) rule is then based on the statistic a + 'ßx. This has the advantage that individual densities f.(x) need not be known and we only need to estimate the parameters a and B.Another advantage, which is claimed , is that the …


Distributed Development And Deployment Of Ontologies For Knowledge-Based Systems, Sameh El-Ansary Sep 2000

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

Archived Theses and Dissertations

No abstract provided.


Algorithm Development For On-Line Control Of The Airborne Laser, Michael W. Oppenheimer Sep 2000

Algorithm Development For On-Line Control Of The Airborne Laser, Michael W. Oppenheimer

Theses and Dissertations

The use of adaptive optics entails the design of a controller. This requires the development of a model of the plant to be controlled, which, in this case, Consists of the atmosphere through which light is traveling. In optics, Zemike polynornials are used as a basis set for the expansion of wavefront phase distortions. Due to the turbulence induced stochastic nature of the underlying process involved, the spatial-temporal correlation functions of the Zemike polynomial phase expansion coefficients must be evaluated if a proper stochastic model of the plant is to be developed and adaptive optics is to be employed. In …


Validation And Verification Of Formal Specifications In Object-Oriented Software Engineering, Steven A. Thomson Sep 2000

Validation And Verification Of Formal Specifications In Object-Oriented Software Engineering, Steven A. Thomson

Theses and Dissertations

The use of formal specifications allows for a software system to be defined with stringent mathematical semantics and syntax via such tools as propositional calculus and set theory. There are many perceived benefits garnered from formal specifications, such as a thorough and in-depth understanding of the domain and system being specified and a reduction in user requirement ambiguity. Probably the greatest benefit of formal specifications, and that which is least capitalized upon, is that mathematical proof procedures can be used to test and prove internal consistency and syntactic correctness in an effort to ensure comprehensive validation and verification (V&V). The …


Knowledge Discovery In Biological Databases : A Neural Network Approach, Qicheng Ma Aug 2000

Knowledge Discovery In Biological Databases : A Neural Network Approach, Qicheng Ma

Dissertations

Knowledge discovery, in databases, also known as data mining, is aimed to find significant information from a set of data. The knowledge to be mined from the dataset may refer to patterns, association rules, classification and clustering rules, and so forth. In this dissertation, we present a neural network approach to finding knowledge in biological databases. Specifically, we propose new methods to process biological sequences in two case studies: the classification of protein sequences and the prediction of E. Coli promoters in DNA sequences. Our proposed methods, based oil neural network architectures combine techniques ranging from Bayesian inference, coding theory, …


Deactivation And Enhancement Effects Of Sulfur On Supported Platinum Oxidation Catalysts, Mark Ladolcetta Aug 2000

Deactivation And Enhancement Effects Of Sulfur On Supported Platinum Oxidation Catalysts, Mark Ladolcetta

Dissertations

The effects of sulfur poisoning on the oxidation activity of 1.5 % Pt/γ-Al2O3, Pt/TiO2, Pt/ZrO2, and Pt/SiO2, were investigated in this study. Each catalyst was poisoned with an H2S/air or SO2/air mixture at 400°C for 24 hours and a sulfur concentration of 200 ppm. The complete oxidation of mixtures of I % CO, methane, ethane, ethene, ethyne, propane, propene, and n-butane in air were measured over fresh and sulfurpoisoned catalysts.

Non-methane alkane oxidation activity was enhanced significantly after sulfur poisoning on all four catalysts. The temperatures …


On Some Self-Organizing Models And Their Applications., Amitava Dutta Dr. Aug 2000

On Some Self-Organizing Models And Their Applications., Amitava Dutta Dr.

Doctoral Theses

Abstract: Self-organizing neural network models constitute the main theme of this thesis. Some well-known self-organizing models are surveyed and their properties are discussed. The application areas on which the thesis focuses are briefly described.This thesis deals with Artificial Neural Network models, in particular, Self- organizing (unsupervisnd) models. We develop here a few self-organizing neural net- work models to solve certain problems which are well studied in the areas of Image Processing and Computationel Geometry and have wide applications in shape eztrac- tion and optimization.1.1 Artificial neural networkThe study of Biological Neural Networks originally comes under biological sciences. They deal with …


Relationships Between Abundance Of Physically Complex Habitat And Benthic Macroinvertebrate Community Parameters In The James River, Nelson County, Va, Tammy Lee Shumaker Aug 2000

Relationships Between Abundance Of Physically Complex Habitat And Benthic Macroinvertebrate Community Parameters In The James River, Nelson County, Va, Tammy Lee Shumaker

Theses & Honors Papers

This study shows the importance of structurally complex habitat on abundance and diversity of organisms in a benthic macroinvertebrate community in the James River, Nelson County, Virginia. Structural complexity was manipulated by attaching stones to five concrete blocks (12.8 ± 0.97% coverage; mean ± SE) and comparing organism abundance on these blocks and blocks lacking stones (0% coverage). Concrete blocks were randomly placed at a site in the James River on November 14, 1999 and collected on December 12, 1999. Macroinvertebrates and particulate organic and inorganic matter on the blocks were collected. Total invertebrate abundance, abundance of eight individual taxa, …


Bioindication Of Atmospheric Heavy Metal Deposition In The Blue Ridge Using The Moss Thuidium Delcatulum, Johathan Scott Schilling Aug 2000

Bioindication Of Atmospheric Heavy Metal Deposition In The Blue Ridge Using The Moss Thuidium Delcatulum, Johathan Scott Schilling

Theses & Honors Papers

Heavy metals in the environment pose a risk to human health as well as to ecosystem health. These metals are released into the atmosphere as a result of industrial processes, and can be transported away from their sources to be deposited into the environment. Ectohydric mosses are known accumulators of atmospheric heavy metals, and their tissue can be used to quantify integrated deposition of these metals over time in the ecosystem.

In this study, the moss Thuidium delicatulum (Hedw.) was used to quantify lead (Pb), copper (Cu), chromium (Cr), and nickel (Ni) concentrations in the central Blue Ridge of Virginia …


The Development Of A Lutetium Recovery Plant, Peter Michael Smith Aug 2000

The Development Of A Lutetium Recovery Plant, Peter Michael Smith

Doctoral Dissertations

This research project focused on the scale-up of an industrial facility for the continuous counter-current solvent extraction (CCCSX) separation of lutetium. CCCSX involves a multistage apparatus for the mixing in each stage of two immiscible liquid phases to transfer an analyte from one phase to the other. The two phases continuously flow in opposite directions in a CCCSX system. In this research, aqueous lutetium solutions, obtained from the acid leaching of lutetium oxyorthosilicate, were mixed with kerosene solutions of phosphorus based metal extractants (e.g. mono-2-ethylhexyl-(2- ethylhexyl) phosphonic acid, MEHEHP). This system extracted the lutetium from the aqueous phase, transferring the …


Laser Spark Ignition Modeling, Ivan George Dors Aug 2000

Laser Spark Ignition Modeling, Ivan George Dors

Doctoral Dissertations

Laser spark phenomena are studied in air and ammonia-oxygen mixtures by the use of a two-dimensional, axially-symmetric, time-accurate computational fluid dynamic model. The initial laser spark temperature distribution is generated to simulate a post-breakdown profile that is consistent with theoretical, experimental, and computational investigations for a nominal 10-ns optical breakdown laser pulse. Thermodynamic properties of various species are extended to 35,000 K to cover the range of the initial temperature distribution. The developed computational model includes a kinetics mechanism that implements plasma equilibrium kinetics in ionized regions.

The computational model time-accurately predicts species concentrations, free electron number density decay, blast …


Reaction Of Caffeic Acid With Amino Acids, Yonggang Wang Aug 2000

Reaction Of Caffeic Acid With Amino Acids, Yonggang Wang

Masters Theses

The reaction of caffeic acid with tryptophan was studied as a model for the reaction of caffeic acid with amino acids in the aquatic environment. Although the autoxidation reaction of caffeic acid in aqueous solution with subsequent dimerization had been previously studied, it was examined as well for comparison purposes. The present studies demonstrate that oxidized caffeic acid would react with tryptophan. The reaction, like the dimerization reaction, was catalyzed by the presence of iron(III) ions at low pH ( <4) and by hydroxide ions at high pH (10). The reaction of caffeic acid with itself yielded six products, four of which were identified by mass spectroscopy as dimers, with the other two being trimers. The reaction of caffeic acid with tryptophan yielded three product peaks. Two of the product peaks had similar retention times to the dimers from the self-reaction of caffeic acid; the third was a new product resulting from the reaction of caffeic acid with the tryptophan.

A mechanism for the reaction of caffeic acid with tryptophan has been proposed. This mechanism was based on the analysis …


Photophysical Study Of Linked 1,4,7-Triazacyclonane Cr (Iii) Complexes, Weizhen Tu Aug 2000

Photophysical Study Of Linked 1,4,7-Triazacyclonane Cr (Iii) Complexes, Weizhen Tu

Masters Theses

A series of mono and bimetallic Cr(III) complexes based on the 1,4,7- triazacyclonoane(TACN) were prepared. Complexes of the Cr(TACN)X3 , and Cr2(DTNE)X6 demonstrated marked difference of photophysical properties on the nature of X. In cases where X is more easily oxidized, enhanced extinction coefficient in the 4A22T, absorption and larger quantum yield of emission at 77K were observed in the dimer complexes. Shorter lifetime and enhanced decay rate were also found in the dimer complexes suggests that there might exists weak coupling behavior between the two Cr(III) metal cents in the …