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2001

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Full-Text Articles in Physical Sciences and Mathematics

Improvement Of Image Alignment Using Camera Attitude Information, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr. Aug 2001

Improvement Of Image Alignment Using Camera Attitude Information, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.

Center for Coastal and Ocean Mapping

We discuss a proposed technique for incorporation of information from a variety of sensors in a video imagery processing pipeline. The auxiliary information allows one to simplify computations, effectively reducing the number of independent parameters in the transformation model. The mosaics produced by this technique are adequate for many applications, in particular habitat mapping. The algorithm, demonstrated through simulations and hardware configuration, is described in detail


Synthesis And Use Of Chiral Surfactants., Xiaoye Yang Aug 2001

Synthesis And Use Of Chiral Surfactants., Xiaoye Yang

Electronic Theses and Dissertations

It has been previously shown that micelles formed from surfactants with chiral head groups serve to induce a chiral reaction medium, leading to enhanced enantioselectivities in the reaction products. This utilization of chiral surfactants will offer an economical alternative to traditional chial solvents while simultaneously reducing organic waste. We have successfully dimethlated S-leucinol in an 85% yield, and have synthesized a hydrocarbon-based surfactant with this molecule as a head group. We have also formed polymeric surfactants that have polydimethylsiloxane as the hydrophobic portion with the (S)-dimethylleucinol as a head group. Tests of the solubility of these surfactants have been conducted. …


Life Annuities Under Random Rates Of Interest., Lesley J. Baker Aug 2001

Life Annuities Under Random Rates Of Interest., Lesley J. Baker

Electronic Theses and Dissertations

We begin by examining the accumulated value functions of some annuities-certain. We then investigate the accumulated value of these annuities where the interest is a random variable under some restrictions. Calculations are derived for the expected value and the variance of these accumulated values and present values. In particular we will examine an annuity-due of k yearly payments of 1. Then we will consider an increasing annuity-due of k yearly payments of 1, 2, ⋯ , k. And finally, we examine a decreasing annuity-due of k yearly payments of n, n - 1, ⋯ , n - k …


Quantum Phase Transition Of Itinerant Helimagnets, Thomas Vojta, Rastko Sknepnek Aug 2001

Quantum Phase Transition Of Itinerant Helimagnets, Thomas Vojta, Rastko Sknepnek

Physics Faculty Research & Creative Works

We investigate the quantum phase transition of itinerant electrons from a paramagnet to a state which displays long-period helical structures due to a Dzyaloshinskii instability of the ferromagnetic state. In particular, we study how the self-generated effective long-range interaction recently identified in itinerant quantum ferromagnets is cut off by the helical ordering. We find that for a sufficiently strong Dzyaloshinskii instability the helimagnetic quantum phase transition is of second order with mean-field exponents. In contrast, for a weak Dzyaloshinskii instability the transition is analogous to that in itinerant quantum ferromagnets, i.e., it is of first order, as has been observed …


X-Ray Photoelectron Spectroscopy (Xps) And Magnetization Studies Of Iron–Vanadium Phosphate Glasses, M. A. Salim, G. D. Khattak, Petru S. Fodor, Lowell E. Wenger Aug 2001

X-Ray Photoelectron Spectroscopy (Xps) And Magnetization Studies Of Iron–Vanadium Phosphate Glasses, M. A. Salim, G. D. Khattak, Petru S. Fodor, Lowell E. Wenger

Physics Faculty Publications

Vanadium phosphate glasses containing Fe2O3 with the chemical composition [(Fe2O3)x(V2O5)0.6−x(P2O5)0.4], where x=0.00, 0.10, 0.20, 0.25 and 0.30, have been prepared and investigated by X-ray photoelectron spectroscopy (XPS) and magnetic susceptibility measurements. The core level binding energies of V 2p, Fe 2p, P 2p and P 2s in the Fe2O3–vanadium phosphate glasses have been measured and shifts from the corresponding binding energies measured for V2O5, Fe2O3 and P2O5 powders are accounted for by changes in the next-nearest neighbor environment of these atoms in the P4O10 local structure. The O 1s spectra for the glasses are single, symmetric peaks arising from nearly …


The Distribution Of Macroinvertebrates Along The Impounded Middle Chattahoochee River, Page Jones Aug 2001

The Distribution Of Macroinvertebrates Along The Impounded Middle Chattahoochee River, Page Jones

Theses and Dissertations

This project was part of a series of investigations designed by the Columbus (Georgia) Water Works to evaluate composition of the macroinvertebrate fauna of the mainstem of the middle Chattahoochee River, as well as its tributaries. An additional objective of the survey was to characterize impacts of storm events on urban streams and the mainstem of the Chattahoochee River. This portion of the study was designed to assess composition of benthic communites of an urbanized river in which flow regime is altered by a series of impoundments. Nine dams currently regulate flow of the mainstem of the middle reach of …


Impact Of A Historical Translocation On Populations Of White-Tailed Deer Odocoileus Virginianus, Nathan Kendall Boddie Aug 2001

Impact Of A Historical Translocation On Populations Of White-Tailed Deer Odocoileus Virginianus, Nathan Kendall Boddie

Theses and Dissertations

Randomly amplified polymorphic DNA (RAPD) analysis was used to study the impact of a historical translocation event on populations of white-tailed deer in Georgia. The technique may also serve as a model by which management practices for other rare species can be studied. Populations from an original translocation source in Wisconsin, another Wisconsin population, and three populations in Georgia were sampled during management hunts. RAPD PCR was used to produce a genetic fingerprint for individuals of each population. Resulting band data were analyzed using PHYLIP genetic analysis software. A consensus tree of 100 bootstrapped replicates showed significant similarity between Georgia …


A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong Aug 2001

A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong

Research Collection School Of Computing and Information Systems

We present a new approach to fast certificate revocation centered around the concept of an on-line semi-trusted mediator (SEM). The use of a SEM in conjunction with a simple threshold variant of the RSA cryptosystem (mediated RSA) offers a number of practical advantages over current revocation techniques. Our approach simplifies validation of digital signatures and enables certificate revocation within legacy systems. It also provides immediate revocation of all security capabilities. This paper discusses both the architecture and implementation of our approach as well as performance and compatibility with the existing infrastructure. Our results show that threshold cryptography is practical for …


A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo Aug 2001

A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo

Research Collection School Of Computing and Information Systems

A distributed intelligent agent-based framework that supports fourth-party logistics optimization under a web-based e-Commerce environment has been proposed in this paper. In the framework, customer job requests come through an e-Procurement service. These requests are consolidated and pushed to the e-Market Place service periodically. The e-Market Place then serves as a broker that allows intelligent agents to bid to serve these requests optimally in real-time by solving multiple instances of underlying logistics optimization problem. The resulting system was implemented based on the Java 2 Enterprise Edition (J2EE) platform using distributed system technology for communication between objects.


Alkyl Nitrates In Dickson During The Sos 1999 Field Campaign, Mei Ma Aug 2001

Alkyl Nitrates In Dickson During The Sos 1999 Field Campaign, Mei Ma

Masters Theses

Measurements of alkyl nitrates were performed during the Southern Oxidants Study (SOS) 1999 Summer Field Campaign in Dickson, TN from June 10 to July 15, 1999. The developed GC-ECD method was tested and used successfully. Nine alkyl nitrates were measured and six alkyl nitrates were quantified. The measured alkyl nitrates expect methyl nitrate showed higher mixing ratios under northeasterly and southeasterly wind, which brought anthropogenic sources to the measurement site, and lower mixing ratios when wind came from northwest and southwest, which brought NOx and clean air, respectively. The contribution of the measured alkyl nitrates to the total oxidized nitrogen …


Empirical Spectral Analysis Of Random Number Generators, David Zeitler Aug 2001

Empirical Spectral Analysis Of Random Number Generators, David Zeitler

Dissertations

Computer simulation procedures have become a staple of research and development in many fields, including statistics. The generation of pseudo random number sequences is the core of computer simulation procedures. Validity of research results often depend on the underlying validity of the generator being used.

In this work we develop the machinery for a class of tests of spatial uniformity based on a multi-dimensional Fourier transform of the empirical probability density function. The test can be adapted to specific requirements and has the added advantage that it has computational complexity that is relatively independent of the number of data points …


Dynamic Hyperpolarizability And Two-Photon Detachment In The Presence Of A Strong Static Electric Field: Application To H-, M.V. Frolov, N.L. Manakov, Anthony F. Starace Aug 2001

Dynamic Hyperpolarizability And Two-Photon Detachment In The Presence Of A Strong Static Electric Field: Application To H-, M.V. Frolov, N.L. Manakov, Anthony F. Starace

Anthony F. Starace Publications

Our recent analysis [J. Phys. B 33, R141 (2000)] of the problem of H- in both laser and strong static electric fields, which treated effects that are linear in the laser intensity l (e.g., the dynamic polarizability and the single-photon detachment cross section), is extended here to treat effects of higher order (∼l2) in the laser intensity (e.g., the dynamic hyperpolarizability, the two-photon detachment cross section, the linear in l corrections to the single-photon detachment rate, etc). We introduce the concept of the dynamic hyperpolarizability of an atom in the presence of a strong electric field …


Synthesis Of Nano-Structured Monoclinic W03 Particles, Zhixiang Lu Aug 2001

Synthesis Of Nano-Structured Monoclinic W03 Particles, Zhixiang Lu

Electronic Theses and Dissertations

The goal of this research is: 1) to develop synthetic methods for generating nanosized particles of monoclinic W03 (m-W03) and 2) to use the high surface area of the nano-sized material in infrared spectroscopic studies of the reactions of gaseous molecules with the particulate surface. Two methods of making nano-structured monoclinic tungsten trioxide (m-W03) particles are investigated. In one method, the sol formation occurs in the presence of a solution containing chelating agents and in a second approach, the sol formation occurs in a water-in oil emulsion. Commercial m-W03 particles are approximately 1 micron …


Simulation Of Engineering Systems Described By High-Index Dae And Discontinuous Ode Using Single Step Methods, Marc Compere Aug 2001

Simulation Of Engineering Systems Described By High-Index Dae And Discontinuous Ode Using Single Step Methods, Marc Compere

Publications

This dissertation presents numerical methods for solving two classes of or-dinary diferential equations (ODE) based on single-step integration meth-ods. The first class of equations addressed describes the mechanical dynamics of constrained multibody systems. These equations are ordinary differential equations (ODE) subject to algebraic constraints. Accordinly they are called differential-algebraic equations (DAE).

Specific contributions made in this area include an explicit transforma-tion between the Hessenberg index-3 form for constrained mechanical systems to a canonical state-space form used in the nonlinear control communities. A hybrid solution method was developed that incorporates both sliding-mode control (SMC) from the controls literature and post-stabilization from …


Groundwater Study Of The Bakers Hill Townsite, Damien Addison Aug 2001

Groundwater Study Of The Bakers Hill Townsite, Damien Addison

Resource management technical reports

A groundwater study was carried out for the townsite of Bakers Hill with the aim of accelerating the implementation of effective salinity management options. The study consisted of a drilling investigation and installation of a piezometer network, a pumping test, groundwater flow modelling and a flood risk analysis.


Groundwater Study Of The Beacon Townsite, F Lewis Aug 2001

Groundwater Study Of The Beacon Townsite, F Lewis

Resource management technical reports

A hydrogeological investigation and a flood risk analysis were carried out for the town of Beacon with the aim of accelerating the implementation of effective salinity management options.


Groundwater Study Of The Narembeen Townsite, Rosemary Knot Aug 2001

Groundwater Study Of The Narembeen Townsite, Rosemary Knot

Resource management technical reports

A groundwater study was carried out for the townsite of Narembeen with the aim of accelerating the implementation of effective salinity management options.


Real-Time Travel Time Estimation Using Macroscopic Traffic Flow Models, Pushkin Kachroo, Kaan Ozbay, Antoine G. Hobeika Aug 2001

Real-Time Travel Time Estimation Using Macroscopic Traffic Flow Models, Pushkin Kachroo, Kaan Ozbay, Antoine G. Hobeika

Electrical & Computer Engineering Faculty Research

This paper presents the estimation of travel time on highways based on macroscopic modelling. The focus is on real-time values as compared to average or static values. The macroscopic models are used for distributed and time/space lumped settings and corresponding travel time estimation functions and algorithms are developed. The implications of these algorithms for the implementation of various incident management and traffic control strategies are also discussed.


A Theoretical Study Of The Interactive Communication Process In Video Game Playing: A Symbolic Interactionist Approach, Nevsal Tiryakioglu Aug 2001

A Theoretical Study Of The Interactive Communication Process In Video Game Playing: A Symbolic Interactionist Approach, Nevsal Tiryakioglu

Masters Theses & Specialist Projects

Video games have become the most popular leisure activity among children and adolescents. The increasing popularity of video games has urged researchers to determine the effects of video game playing on youngsters. Given the fact that most popular video games are violent in nature, much of the research has primarily focused on the correlation between playing video games with violent content and aggressive behavior in children. Most researchers have relied on previous media violence research, assuming similarities between television viewing and video game playing. However, video games are interactive media allowing the player to participate in the game scenario, which …


Dye Tracing To Delineate Drainage Basins And Determine Groundwater Sensitivity, Mammoth Cave, Kentucky; With Special Reference To Potential Groundwater Contamination From Spills Along Interstate I-65, Arthur Capps Aug 2001

Dye Tracing To Delineate Drainage Basins And Determine Groundwater Sensitivity, Mammoth Cave, Kentucky; With Special Reference To Potential Groundwater Contamination From Spills Along Interstate I-65, Arthur Capps

Masters Theses & Specialist Projects

The Mammoth Cave System of south central Kentucky encompasses more than 560 km of surveyed cave passages. The largest groundwater basin (244 km2) found within this cave system emerges from the Turnhole Bend Spring on the Green River. During high flow conditions, water from this groundwater basin will spill over into the Echo River section of the cave. Previous research, including cave mapping and dye tracing (Quinlan and Ray, 1989; Currens and Ray, 1998; Coons, 1994), has delineated the boundaries of spring groundwater basins for numerous springs along the Green and Barren Rivers. These data showed that 60% of the …


Metalation Of The Di- And Tri-Methoxybenzenes, Phillip Shelton Aug 2001

Metalation Of The Di- And Tri-Methoxybenzenes, Phillip Shelton

Masters Theses & Specialist Projects

Hydrocarbon solvents are known to be unreactive towards organolithium reagents and also to afford little support for ortho-metalation reactions. In contrast, both m- and odimethoxybenzene afford 80% "ion-multiple specific" monometalation in hydrocarbon solvent (n-hexane, cyclohexane, toluene) without the addition of any catalyst (ether or amine). These observations are, in part, attributed to the 1,2- and 1,3- formation of the n-BuLi dimer, the most reactive form of n-BuLi. In other words these substrates are acting in a "substrate-catalyzed" manner. Extensions of these concepts to 1,2,3-, 1,2,4- and 1,3,5-trimethoxybenzenes have led to further unusual observations. In particular, the 1,2,3-system affords an interesting …


A Qualitative Investigation Of The Polymerization Process In The Ihss Humic Substances Extraction Procedure Using Model Phenolic Compounds, Roger J. Germay Aug 2001

A Qualitative Investigation Of The Polymerization Process In The Ihss Humic Substances Extraction Procedure Using Model Phenolic Compounds, Roger J. Germay

Masters Theses

Achard (1786) extracted peat with alkali and reported obtaining dark compounds now called humic substances. These are complex, high molecular weight, polyphenolic compounds naturally occurring in soil, in fresh-water and in marine environments. They are biodegradation products of plant materials.

The International Humic Substances Society (IHSS) adapted Achard's method to separate humic substances into three fractions: (1) humic acids (HA), soluble only at high pH; (2) fulvic acids (FA), water-soluble at any pH; and (3) humin, insoluble at any pH. The IHSS method involves contact of soil with 0.1N.NaOH solution, followed by acidification with HCl.

In this study, 0.01 N. …


Generating Market Basket Data With Temporal Information, Yingjiu Li, Peng Ning, X. Sean Wang, Sushil Jajodia Aug 2001

Generating Market Basket Data With Temporal Information, Yingjiu Li, Peng Ning, X. Sean Wang, Sushil Jajodia

Research Collection School Of Computing and Information Systems

This paper presents a synthetic data generator that outputs timestamped transactional data with embedded temporal patterns controlled by a set of input parameters. In particular, calendar schema, which is determined by a hierarchy of input time granularities, is used as a framework of possible temporal patterns. An example of calendar schema is (year, month, day), which provides a framework for calendar-based temporal patterns of the form -38352 , where each is either an integer or the symbol . For example, is such a pattern, which corresponds to the time intervals consisting of all the 16th days of all months in …


Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das Aug 2001

Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das

Research Collection School Of Computing and Information Systems

In the vision of pervasive computing, users will exchange information and control their environments from anywhere using various wireline/wireless networks and computing devices. We believe that current protocols, such as DHCP, PPP, and Mobile IP, must be enhanced to support pervasive network access. In particular, this article identifies three fundamental functions: autoconfiguration, registration, and mobility management, that need such enhancements. Realizing that the IP autoconfiguration capabilities must be extended to configure routers and large dynamic networks, we first describe our autoconfiguration solution based on the dynamic configuration and distribution protocol (DCDP). Second, we discuss why providing user-specific services over a …


Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin Aug 2001

Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin

Research Collection School Of Computing and Information Systems

We present a novel approach for video partitioning by detecting three essential types of camera breaks, namely cuts, wipes, and dissolves. The approach is based on the analysis of temporal slices which are extracted from the video by slicing through the sequence of video frames and collecting temporal signatures. Each of these slices contains both spatial and temporal information from which coherent regions are indicative of uninterrupted video partitions separated by camera breaks. Properties could further be extracted from the slice for both the detection and classification of camera breaks. For example, cut and wipes are detected by color-texture properties, …


Visual Iconic Object-Oriented Programming To Advance Computer Science Education And Novice Programming, Nancy Silva Martinez Aug 2001

Visual Iconic Object-Oriented Programming To Advance Computer Science Education And Novice Programming, Nancy Silva Martinez

Theses and Dissertations - UTB/UTPA

Learning how to program a computer is difficult for most people. Computer programming is a cognitively challenging, time consuming, labor intensive, and frustrating endeavor. Years of formal study and training are required to learn a programming language's world of algorithms and data structures. Instructions are coded in advance before the computer demonstrates the desired behavior. Seeing all the programming steps and instruction code is complicated. There exists a tremendous gap between the representations the human brain uses when thinking about a problem and the representations used in programming a computer. Often people are much better at dealing with specific, concrete …


Signature Lipids And Stable Carbon Isotope Analyses Of Octopus Spring Hyperthermophilic Communities Compared With Those Of Aquificales Representatives, Linda L. Jahnke, Wolfgang Eder, Robert Huber, Janet M. Hope, Kai-Uwe Hinrichs, John M. Hayes, David J. Des Marais, Sherry L. Cady, Roger E. Summons Aug 2001

Signature Lipids And Stable Carbon Isotope Analyses Of Octopus Spring Hyperthermophilic Communities Compared With Those Of Aquificales Representatives, Linda L. Jahnke, Wolfgang Eder, Robert Huber, Janet M. Hope, Kai-Uwe Hinrichs, John M. Hayes, David J. Des Marais, Sherry L. Cady, Roger E. Summons

Geology Faculty Publications and Presentations

The molecular and isotopic compositions of lipid biomarkers of cultured Aquificales genera have been used to study the community and trophic structure of the hyperthermophilic pink streamers and vent biofilm from Octopus Spring. Thermocrinis ruber, Thermocrinis sp. strain HI 11/12, Hydrogenobacter thermophilus TK-6, Aquifex pyrophilus, and Aquifex aeolicus all contained glycerol-ether phospholipids as well as acyl glycerides. The n-C20:1 and cy-C21 fatty acids dominated all of the Aquificales, while the alkyl glycerol ethers were mainly C18:0. These Aquificales biomarkers were major constituents of the lipid extracts of two Octopus Spring samples, a biofilm associated with the siliceous vent walls, and …


Environmental Change And The Central Great Plains, Carbon Sequestration, Mark A. Mesarch Aug 2001

Environmental Change And The Central Great Plains, Carbon Sequestration, Mark A. Mesarch

Conservation and Survey Division

No abstract provided.


Managing Birds And Controlling Aircraft In The Kennedy Airport–Jamaica Bay Wildlife Refuge Complex: The Need For Hard Data And Soft Opinions, Kevin Brown, R. Michael Erwin, Milo E. Richmond, P A. Buckley, John Tanacredi Ph.D., Dave Avrin Aug 2001

Managing Birds And Controlling Aircraft In The Kennedy Airport–Jamaica Bay Wildlife Refuge Complex: The Need For Hard Data And Soft Opinions, Kevin Brown, R. Michael Erwin, Milo E. Richmond, P A. Buckley, John Tanacredi Ph.D., Dave Avrin

Faculty Works: CERCOM (1977-2016)

During the 1980s, the exponential growth of laughing gull (Larus atricilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes, at the airport; …


Vortex-Defect Interactions In High-Temperature Superconductors, Valentina Tobos Aug 2001

Vortex-Defect Interactions In High-Temperature Superconductors, Valentina Tobos

Dissertations

The topics covered in this thesis are related to two objectives: one refers to the search for methods of improving die critical current density of high-temperature superconductors, a subject which remains of continuing interest for its importance in technological applications. The other direction is aimed at clarifying the phase diagram of high-Tc materials.

The interaction between the structural defects and the vortex system plays a significant role in the capability of these materials to carry large electrical transport currents. Through proton irradiation induced defects we follow the evolution of the critical current density, and its enhancement with increasing point-like defects …