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2004

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Utb-Tsc Academic Senate Meeting - President's Report 2004-12-17, University Of Texas At Brownsville And Texas Southmost College. Faculty Senate. Dec 2004

Utb-Tsc Academic Senate Meeting - President's Report 2004-12-17, University Of Texas At Brownsville And Texas Southmost College. Faculty Senate.

UTB/TSC Faculty Senate Administrative Documents

No abstract provided.

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Distribution And Ecology Of Exotic Plants In Wrangell-St. Elias National Park And Preserve, Alaska, Paul Christian Mckee Dec 2004

Distribution And Ecology Of Exotic Plants In Wrangell-St. Elias National Park And Preserve, Alaska, Paul Christian Mckee

Natural Resources

The distribution of exotic plants and site factors influencing their abundance on roads and trails were studied in Wrangell-St. Elias National Park and Preserve during the summer of 2003. Seventeen species of exotic plants were found in the park at 173 locations. The most common species (Taraxacum officinale, Plantago major) were present at all study sites, while some (Trifolium spp., Bromus inermis, Leucanthemum vulgare) were restricted to specific disturbance types and particular areas. Though sampling was limited to areas in which exotic plants were growing, percent cover of exotics was not a significant component of sample sites, and exotic species …

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Transient Spatiotemporal Chaos On Complex Networks, Safia Rawoot Dec 2004

Transient Spatiotemporal Chaos On Complex Networks, Safia Rawoot

Physics

Some of today's most important questions regard complex dynamical systems with many interacting components. Network models provide a means to gain insight into such systems. This thesis focuses on a network model based upon the Gray-Scott cubic autocatalytic reaction-diffusion system that manifests transient spatiotemporal chaos. Motivated by recent studies on the small-world topology discovered by Watts and Strogatz, the network's original regular ring topology was modified by the addition of a few irregular connections. The effects of these added connections on the system's transience as well on the dynamics local to the added connections were examined. It was found that …

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Synchronization In Biological Systems, Jonathan P. Klaas Dec 2004

Synchronization In Biological Systems, Jonathan P. Klaas

Physics

Synchronization, the adjustment of rhythms via coupling, is an essentially nonlinear effect in coupled dynamical systems. Synchronization is observed in many systems, for example the moon's periods of rotation and revolution, in pendulums suspended from a common support, in swarms of fireflies that flash in unison, and in biological circadian rhythms. Circadian rhythms are periodic fluctuations in multiple physiological systems that have evolved as a consequence of the daily rotation of the earth. These rhythms have been observed in organisms ranging from cyanobacteria to man. In this thesis we will present a conceptually simple model of circadian rhythms to yield …

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Soil Properties And Forest Stand Characteristics Along A Toposequence Of The Smith Lake Area Near Fairbanks, Alaska, Lijie Zhu Dec 2004

Soil Properties And Forest Stand Characteristics Along A Toposequence Of The Smith Lake Area Near Fairbanks, Alaska, Lijie Zhu

Plant, Animal and Soil Sciences

Forests, soils and their relationships were studied along a toposequence over an elevation range from 161 meters to 213 meters near Smith Lake on the University of Alaska Fairbanks campus, Fairbanks, Alaska. Forest cover type and understory species composition change along the slope from top to bottom and are related to temperature and moisture. Aspen occurs on the ridge top. Paper birch grows best on the shoulder. White spruce, which has the greatest commercial value, is the only species present on all slope positions; it grows best on shoulder and back slopes. Black spruce dominates on the wet and cold …

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Tribological Comparison Of Materials, Bing Shi Dec 2004

Tribological Comparison Of Materials, Bing Shi

Chemistry and Biochemistry

Approximately 600,000 total joint replacement surgeries are performed each year in the United States. Current artificial joint implants are mainly metal-on-plastic. The synthetic biomaterials undergo degradation through fatigue and corrosive wear from load-bearing and the aqueous ionic environment of the human body. Deposits o f inorganic salts can scratch weight-bearing surfaces, making artificial joints stiff and awkward. The excessive wear debris from polyethylene leads to osteolysis and potential loosening of the prosthesis. The lifetime for well-designed artificial joints is at most 10 to 15 years. A patient can usually have two total joint replacements during her/his lifetime. Durability is limited …

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Who's "Fat", Who's Not: Sociocultural Influences On Female Adolescent's Body Image, Lindsay Astheimer Paxton Dec 2004

Who's "Fat", Who's Not: Sociocultural Influences On Female Adolescent's Body Image, Lindsay Astheimer Paxton

Counseling

Sociocultural influences, media, parents and peers, on adolescent females' body image, as perceived by female high school students of a military related community were investigated. A body image survey was administered to 26 adolescent females. Ultimately, the research revealed that media, parents and peer groups influenced adolescent body image and significantly contributed to female students' perceptions and attitudes.

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Market Opportunities For Carbon Sequestration In Alaska, Jennifer Elizabeth Duval Dec 2004

Market Opportunities For Carbon Sequestration In Alaska, Jennifer Elizabeth Duval

Economics

Global climate change has been at the forefront of environmental concerns for the last few decades. Based on the success of the United States' sulfur dioxide cap-and-trade program, a market for greenhouse gas emissions has slowly emerged. Russia's recent ratification of the Kyoto Protocol will bring an international market into force in February 2005. This thesis examines the economic theory behind cap-and-trade markets as solutions for environmental problems and discusses the characteristics of the markets for greenhouse gas emissions. The opportunities for Alaska's participation are examined, particularly offsetting diesel emissions from rural generators with wood or alternative energies. The calculations …

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2004 Fall Commencement Program: Winona State University, Winona State University Dec 2004

2004 Fall Commencement Program: Winona State University, Winona State University

WSU Commencement Programs

This is the Winona State University Fall 2004 commencement program. Commencement was on Friday, December 17, 2004.

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Oscillatory Interlayer Exchange Coupling In [Pt/Co]N/Nio/[Co/Pt]N Multilayers With Perpendicular Anisotropy: Dependence On Nio And Pt Layer Thicknesses, Z. Y. Liu, Lanping Yue, D. J. Keavney, Shireen Adenwalla Dec 2004

Oscillatory Interlayer Exchange Coupling In [Pt/Co]N/Nio/[Co/Pt]N Multilayers With Perpendicular Anisotropy: Dependence On Nio And Pt Layer Thicknesses, Z. Y. Liu, Lanping Yue, D. J. Keavney, Shireen Adenwalla

Materials Research Science and Engineering Center: Faculty Publications

Interlayer exchange coupling has been studied in a series of [Pt( tPt Å)/Co(4 Å)]n/NiO( tNiO)/[Co(4 Å)/Pt( tPt Å)]n multilayers with perpendicular anisotropy. The coupling oscillates between antiferromagnetic and ferromagnetic as a function of tNiO with a period of ~5 Å, and the oscillatory behavior is related to the antiferromagnetic ordering of the NiO layer. This interlayer coupling between two Co/Pt multilayers is shown to occur domain by domain by magnetic force microscopy imaging. For the strongest antiferromagnetic coupling at tNiO = 11 Å, an oscillation with a period of ~6 Å is superposed …

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Three Factor Authentication Using Java Ring And Biometrics, Jyothi Chitiprolu Dec 2004

Three Factor Authentication Using Java Ring And Biometrics, Jyothi Chitiprolu

LSU New Orleans Theses and Dissertations

Computer security is a growing field in the IT industry. One of the important aspects of the computer security is authentication. Using passwords (something you know) is one of the most common ways of authentications. But passwords have proven to provide weak level of security as they can be easily compromised. Some other ways of authenticating a user are using physical tokens, (something you possess) and biometrics, (something you are). Using any one of these techniques to secure a system always has its own set of threats. One way to make sure a system is secure is to use multiple …

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Algorithms And Data Structures For Automated Change Detection And Classification Of Sidescan Sonar Imagery, Marlin Gendron Dec 2004

Algorithms And Data Structures For Automated Change Detection And Classification Of Sidescan Sonar Imagery, Marlin Gendron

LSU New Orleans Theses and Dissertations

During Mine Warfare (MIW) operations, MIW analysts perform change detection by visually comparing historical sidescan sonar imagery (SSI) collected by a sidescan sonar with recently collected SSI in an attempt to identify objects (which might be explosive mines) placed at sea since the last time the area was surveyed. This dissertation presents a data structure and three algorithms, developed by the author, that are part of an automated change detection and classification (ACDC) system. MIW analysts at the Naval Oceanographic Office, to reduce the amount of time to perform change detection, are currently using ACDC. The dissertation introductory chapter gives …

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University Of Nebraska At Omaha, December Commencement 2004, University Of Nebraska At Omaha Dec 2004

University Of Nebraska At Omaha, December Commencement 2004, University Of Nebraska At Omaha

Commencement Programs

No abstract provided.

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A Quest For Making A Difference One Life At A Time, Tracie Farner Dempsey Dec 2004

A Quest For Making A Difference One Life At A Time, Tracie Farner Dempsey

Digitized Theses and Dissertations (prior to 2008)

A Portfolio Submitted to the Graduate Faculty of Kennesaw State University In partial fulfillment of the Requirements for the degree MASTER OF EDUCATION IN ADOLESCENT EDUCATION- Science

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A Comparison Of Multiple-Model Target Tracking Algorithms, Ryan Pitre Dec 2004

A Comparison Of Multiple-Model Target Tracking Algorithms, Ryan Pitre

LSU New Orleans Theses and Dissertations

There are many multiple-model (MM) target-tracking algorithms that are available but there has yet to be a comparison that includes all of them. This work compares seven of the currently most popular MM algorithms in terms of performance, credibility, and computational complexity. The algorithms to be considered are the autonomous multiple-model algorithm, generalized pseudo- Bayesian of first order, generalized pseudo-Bayesian of second order, interacting multiple-model algorithm, B-Best algorithm, Viterbi algorithm, and reweighted interacting multiple-model algorithm. The algorithms were compared using three scenarios consisting of maneuvers that were both in and out of the model set. Based on this comparison, there …

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Dynamic Website And Data Engine Generators For Distributed Enterprise/Business Architectures, Fareed Qaddoura Dec 2004

Dynamic Website And Data Engine Generators For Distributed Enterprise/Business Architectures, Fareed Qaddoura

LSU New Orleans Theses and Dissertations

Creating websites providing dynamic services is an extensive process. Intelligent systems are used to create websites with dynamic services. Current intelligent systems are hard to use and configure by the average user. The generated websites are usually custom built to solve one problem and cannot be fully customizable for users on different environments. This thesis presents a technological solution that enables the average user to create websites with dynamic services by providing a number of parameters. The website generator is a web-based application that generates all the components of the website. The components act as portlets and the generated website …

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Relationship Between The Sludge Settling Characteristics And The Parameters Of The Activated Sludge System, Jose Angel Rojas Dec 2004

Relationship Between The Sludge Settling Characteristics And The Parameters Of The Activated Sludge System, Jose Angel Rojas

LSU New Orleans Theses and Dissertations

The activated sludge process is one of the most commonly employed domestic and industrial waste treatment process. Different types of mathematical models have been proposed for design and operation of this process, most of which do not consider the relationship between the sludge settling characteristics and the aeration unit performance. This project studies the validity of a model developed by La Motta (2004b) which links the operating parameters of an activated sludge system and the classical limiting flux sludge settling theory. Favorable results were obtained demonstrating that the model predicts very similar values of the parameters of the system in …

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Secondary Municipal Wastewater Treatment Using The Uasb/Solids Contact Technology, Eudomar Silva Dec 2004

Secondary Municipal Wastewater Treatment Using The Uasb/Solids Contact Technology, Eudomar Silva

LSU New Orleans Theses and Dissertations

Anaerobic pretreatment and aerobic post-treatment of municipal wastewater is being used more frequently. Recent investigations in this field using an AFBR/aeration chamber combination demonstrated the technical feasibility of this process. The investigation presented herein describes the use of a combined UASB/aeration chamber system for the treatment of municipal wastewater and attempts to demonstrate the technical feasibility of using the UASB process as both a pretreatment unit and a waste activated sludge digestion system. The results indicate that the UASB reactor has a TSS removal efficiency of about 37%. Of the solids removed by the unit, 33% were degraded by the …

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A Novel Chirp Slope Keying Modulation Scheme For Underwater Communication, Lastri Simanjuntak Dec 2004

A Novel Chirp Slope Keying Modulation Scheme For Underwater Communication, Lastri Simanjuntak

LSU New Orleans Theses and Dissertations

A digital modulation method using Chirp-Slope Keying (CSK) is developed for coherent underwater acoustic communications. Effective signal detection is a critical stage in the implementation of any communications system; we will see that CSK solves some significant challenges to reliable detection. This thesis is primarily based on analyzing the effectiveness of CSK through simulations using Matlab's Simulink for underwater communications. The procedure begins with modulating a chirp's slope by random binary data with a linear-down-slope chirp representing a 0, and a linear-up-slope chirp representing a 1. Each received symbol is demodulated by multiplying it with the exact linear-up-slope chirp and …

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Biomimetics And Host-Guest Chemistry, Jiachang Gong Dec 2004

Biomimetics And Host-Guest Chemistry, Jiachang Gong

LSU New Orleans Theses and Dissertations

In an effort to produce the tetrahedrally coordinated, catalytically active zinc center, three families of tris(2-pyridyl)methanol derivatives were synthesized and characterized. Zinc binding studies revealed that the binding behaviors of the ligands depended on the steric and electronic properties of the substituents on the pyridyl rings, as well as the functional group on the tertiary alcohol. A novel tris-pyridyl macrocyclic receptor was synthesized. The receptor possesses both hydrogen bond donors and acceptors. NMR titration experiments revealed that the receptor simultaneously bound both ammonium cation and the counter anion. The counter anion significantly influences the association between the receptor and the …

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Physical Volcanology Of A Sub-Plinian And Phreatomagmatic Eruption At Okmok Volcano, Alaska: Implications For Explosive Mafic Volcanism, Lily J. Wong Dec 2004

Physical Volcanology Of A Sub-Plinian And Phreatomagmatic Eruption At Okmok Volcano, Alaska: Implications For Explosive Mafic Volcanism, Lily J. Wong

Geosciences

The Middle Scoria Unit (M.S.) of Okmok Volcano is a basaltic andesite (̃54 wt. % SiO₂) fall deposit that is stratigraphically located between two caldera-forming eruptions (̃12,000 and 2050 y B.P.). Stratigraphy, geochemistry, vesicularity, and crystallinity data imply that the M.S. erupted in three phases that began with an initial phreatomagmatic phase followed by a sub-Plinian phase caused by rapid ascent of magma. The sequence culminates with short-lived Vulcanian eruptions that demonstrate a strong magmatic influence and a possible decrease in ascent rate. The M.S. covers ̃300 km² and averages about 2 m thick. Estimates from this work suggest a …

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International Cross Section Estimates Of Demand For Use In The Gtap Model, Jeffrey J. Reimer, Thomas W. Hertel Dec 2004

International Cross Section Estimates Of Demand For Use In The Gtap Model, Jeffrey J. Reimer, Thomas W. Hertel

GTAP Technical Papers Archive

The making of projections often requires an economy-wide perspective, and the estimation of consumer demands at the international level. In this paper, an implicit, directly additive demand system (AIDADS) is estimated using cross-country data on consumer expenditures from the International Comparison Program (ICP), and then from Global Trade Analysis Project (GTAP) data. The two data sets are found to produce results that are quite consistent despite their differing origins, and the fact that the former is based on consumer goods that embody wholesale/retail margins, while margin demands are treated separately in GTAP. Given the similarity of the results, the estimation …

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Winter Commencement: December 17, 2004, University Of North Dakota Dec 2004

Winter Commencement: December 17, 2004, University Of North Dakota

UND Commencement Programs

UND Winter Commencement program from December 17, 2004.

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Non-Linear Dynamics Of Marine Ecosystem Models, Georgina Anne Gibson Dec 2004

Non-Linear Dynamics Of Marine Ecosystem Models, Georgina Anne Gibson

Marine Biology

Despite a rapid trend towards more realistic Nutrient-Phytoplankton-Zooplankton (NPZ) models, in which zooplankton are presented with multiple nutritional resources, investigations into the fundamental dynamics of these newer models have been limited. The objective of this dissertation was to explore the dynamical behavior of such NPZ models parameterized for the coastal Gulf of Alaska. With alternative stationary forcing regimes and zooplankton grazing functions, the dynamics of one-dimensional NPZ models were investigated for a range of specific predation rates (h) and predation exponents (q), which together define the form of the predation (model closure) function. Oscillations in state variables are shown to …

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Characterizing Glucocorticoid Levels In Five Species Of Sea Ducks Occurring In Alaska, Peter B. Nilsson Dec 2004

Characterizing Glucocorticoid Levels In Five Species Of Sea Ducks Occurring In Alaska, Peter B. Nilsson

Marine Biology

Stress hormone analysis, used in conjunction with other physiological parameters, may help identify factors affecting sea duck populations in their natural environment. Corticosterone, the primary 'stress hormone' in birds, is secreted in response to a stressor and enhances an individual's chance of survival by inducing physiological and behavioral changes. Establishing a valid method for evaluating stress hormone levels in sea ducks and gaining basic information on baseline concentrations and stress response in these birds are important first steps to identify factors that may negatively affect sea duck populations. This study validated a radioimmunoassay (RIA) procedure to measure corticosterone concentrations in …

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Voice Of The Dead, Anthony Carl Derrico Dec 2004

Voice Of The Dead, Anthony Carl Derrico

LSU New Orleans Theses and Dissertations

N/A

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Employee Satisfaction And Performance: A Study Of The Rc Hotel Company Kitchen Environment, Melissa Bradberry Sims Dec 2004

Employee Satisfaction And Performance: A Study Of The Rc Hotel Company Kitchen Environment, Melissa Bradberry Sims

LSU New Orleans Theses and Dissertations

Employee satisfaction and performance are a major determinant of the corporate culture of a property. Discussion of whether or not this statement is true within the kitchens of The Ritz Carlton Hotel in New Orleans is the basis for this study. By using the corporate mandated tools (the annual employee satisfaction survey and the employee performance appraisals) the determination of this question was confirmed. However, there were some great concerns about the validity of the two tools. The tools showed a definite relationship between the employee satisfaction survey and the performance appraisal, as well as a negative employee perception of …

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Study Of Bis-Imidazol-2-Ylidines As Ligands For Transition Metal Catalyzed Coupling Reactions, Stanhope Turnbull Dec 2004

Study Of Bis-Imidazol-2-Ylidines As Ligands For Transition Metal Catalyzed Coupling Reactions, Stanhope Turnbull

LSU New Orleans Theses and Dissertations

Two bis-imidazol-2-ylidine N-heterocyclic carbenes have been employed as ancillary ligands in an attempt to illustrate their utility in the palladium-mediated preparation of aryl ethers from aryl halides. Ullman-type homo-coupling of the aryl halides persistently occurred instead of ether formation. One of the well known N-heterocyclic carbenes, IPr, was employed with the same results. A variety of reaction conditions and reagents were investigated including solvents, N-heterocyclic carbene species, palladium source, alkoxide base, palladium to ligand ratio and reaction time. Reactivity of the individual N-heterocyclic carbenes as ancillary ligands in the palladium-catalyzed amination reaction of aryl halides was investigated to determine functionality …

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Biosorption Of Heavy Metals By Citrus Fruit Waste Materials, Santosh Bramhadev Patil Dec 2004

Biosorption Of Heavy Metals By Citrus Fruit Waste Materials, Santosh Bramhadev Patil

Engineering

Conventionally used processes for removing heavy metals from wastewater are usually either expensive, such as ion exchange, or inefficient, such as precipitation. An innovative technique that is both efficient and economical is biosorption, in which living and dead biomass can act as biosorbents through physical-chemical processes like ion exchange and micro-precipitation. Pectin, a structural polysaccharide present in plant cell walls, is similar to alginate, a molecule that is often responsible for the high metal uptake by algae. Based on the structural similarity between alginate and pectin, it was expected that pectin rich bio-wastes may be as good a biosorbent material …

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How Chemical Differences In Dissolved Organic Matter Relate To Vegetation, Sarah Jean Seelen Dec 2004

How Chemical Differences In Dissolved Organic Matter Relate To Vegetation, Sarah Jean Seelen

Engineering

The purpose of this study was to better understand the link between dissolved organic matter (DOM) in soil leachate and different vegetation attributes. Soil cores were collected from the Caribou Poker Creeks Research Watershed (CPCRW) and subjected to a laboratory leaching procedure. The leachates were then subjected to a number of analytical tests, including pyrolysis-gas chromatography/mass spectrometry (py-GC/MS). Py-GC/MS is a 'molecular fingerprinting' technique that was used to help determine similarities and differences in organic matter leached from soils with different vegetation attributes. Numerous statistical tests were performed including Student-t, analysis of variance, principal components analysis, and partial least squares …

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