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Full-Text Articles in Physical Sciences and Mathematics

On The Nature Of Connectivity Types, Miao Xu May 2005

On The Nature Of Connectivity Types, Miao Xu

Honors Theses

No abstract provided.


Dynamical Systems And The Logistic And Tent Maps, Kathleen Larkin Spires May 2005

Dynamical Systems And The Logistic And Tent Maps, Kathleen Larkin Spires

Honors Theses

No abstract provided.


Ensight, Jonathan Hefner May 2005

Ensight, Jonathan Hefner

Honors Theses

No abstract provided.


An Investigation Of Modified Superconductivity Through Structural Alteration Of Mgcni3 And Mgb2, Nathan L. Henderson Apr 2005

An Investigation Of Modified Superconductivity Through Structural Alteration Of Mgcni3 And Mgb2, Nathan L. Henderson

Honors Theses

No abstract provided.


Using Ground Penetrating Radar, Light Detection And Ranging, Geodetic Leveling, And Area Hydrogeology To Study The Baton Rouge And Scotlandville Faults, East Baton Rouge Parish, La, Angela Mooi Thomas Jan 2005

Using Ground Penetrating Radar, Light Detection And Ranging, Geodetic Leveling, And Area Hydrogeology To Study The Baton Rouge And Scotlandville Faults, East Baton Rouge Parish, La, Angela Mooi Thomas

LSU Master's Theses

East Baton Rouge Parish, Louisiana, is situated on at least two faults, the Baton Rouge Fault and the Denham Springs-Scotlandville Fault. These faults have surface expressions in the form of escarpments and damage to man-made structures. The purpose of this thesis is to study these faults in the shallow subsurface, in climate and soils found in Louisiana, and to study their ability to block fluid flow and whether groundwater withdrawal influences the amount and rate of subsidence along these faults. Techniques used to gather field data or to research and compile previously acquired data for this thesis includes: Ground Penetrating …


Multiscale Strain Analysis, Timothy Donald Breitzman Jan 2005

Multiscale Strain Analysis, Timothy Donald Breitzman

LSU Doctoral Dissertations

The mathematical homogenization and corrector theory relevant to prestressed heterogeneous materials in the linear-elastic regime is discussed. A suitable corrector theory is derived to reconstruct the local strain field inside the composite. Based on this theory, we develop an inexpensive numerical method for multi scale strain analysis within a prestressed heterogeneous material. The theory also provides a characterization of the macroscopic strength domain. The strength domain places constraints on the homogenized strain field which guarantee that the actual strain in the heterogeneous material lies inside the strength domain of each material participating in the structure.


Simulation Study Of Routing Protocols In Wireless Sensor Networks, Vatsalya Kunchakarra Jan 2005

Simulation Study Of Routing Protocols In Wireless Sensor Networks, Vatsalya Kunchakarra

LSU Master's Theses

Wireless sensor networks, a distributed network of sensor nodes perform critical tasks in many application areas such as target tracking in military applications, detection of catastrophic events, environment monitoring, health applications etc. The routing protocols developed for these distributed sensor networks need to be energy efficient and scalable. To create a better understanding of the performance of various routing protocols proposed it is very important to perform a detailed analysis of them. Network simulators enable us to study the performance and behavior of these protocols on various network topologies. Many Sensor Network frameworks were developed to explore both the networking …


Molluscan Taphonomy As A Proxy For Recognizing Fossil Seagrass Beds, Jill Suzanne Leonard-Pingel Jan 2005

Molluscan Taphonomy As A Proxy For Recognizing Fossil Seagrass Beds, Jill Suzanne Leonard-Pingel

LSU Master's Theses

Seagrass beds, important marine ecosystems both economically and environmentally, have a poor fossil record. As a result, little is known about the geographic distribution of seagrasses over historic and geologic time, or their abundance when unaltered by anthropogenic effects. The purpose of this study is to define a taphonomic signature unique to seagrass beds that can be used as a proxy for identifying the seagrass habitat in the fossil record. In order to develop this proxy, sediment samples from Recent seagrass and non-seagrass environments were collected, and the molluscan bioclasts from these samples were categorically ranked for the following taphonomic …


A Bioeconomic Supply Model For Louisiana Nutria And Impacts On Wetlands Conservation Associated With Economic Incentives, Cheikhna Ould Dedah Jan 2005

A Bioeconomic Supply Model For Louisiana Nutria And Impacts On Wetlands Conservation Associated With Economic Incentives, Cheikhna Ould Dedah

LSU Master's Theses

Nutria (Mayocastor) were first introduced to Louisiana in 1938. With few natural predators and high prolific productivity, they became well established in the surrounding coastal marsh within a few years. Prior to 1980’s, as a result of high demand for nutria products from European countries, harvest pressure was sufficient to keep the population in ‘check’ with their wetlands capacity. By the mid-1980’s, however, prices had fallen sharply, culminating in declining annual harvests and an increasing population. Because of their feeding habits, the increased nutria population has resulted in a substantial amount of wetland degradation. In this thesis, a long-run bioeconomic …


Benthic Communities In The Northern Gulf Of Mexico Hypoxic Area: Potential Prey For Demersal Fish, Melissa Millman Baustian Jan 2005

Benthic Communities In The Northern Gulf Of Mexico Hypoxic Area: Potential Prey For Demersal Fish, Melissa Millman Baustian

LSU Master's Theses

Bottom-water hypoxia (≤2 mg O2 l-1) usually occurs on an annual basis on the Louisiana/Texas continental shelf from mid-May through mid-September over a large area (up to 20,000 km2 in mid-summer). The effects of hypoxia on the benthic infauna (potential prey) for demersal fish were examined, because changes in optimal diet can lead to negative impacts on growth and reproduction. Benthic samples were taken in three areas (inshore and offshore out of hypoxia and in the hypoxic area) during August 2003. Samples were also taken monthly from September 2003 to October 2004 at a fixed station …


Hydrophobic Guar Gum Derivatives Prepared By Controlled Grafting Processes For Hydraulic Facturing Applications, Ahmad Bahamdan Jan 2005

Hydrophobic Guar Gum Derivatives Prepared By Controlled Grafting Processes For Hydraulic Facturing Applications, Ahmad Bahamdan

LSU Doctoral Dissertations

The synthesis of new water soluble guar gum derivatives is described. Introduction of polyalkoxyalkyleneamide grafts to guar gum or hydroxyopropyl guar was achieved in a three step process: carboxymethylation with sodium chloroacetate, esterification with dimethyl sulfate and amidation with a series of polyalkoxyalkylene-amines. The process steps were followed using infrared spectroscopy; the grafted guar derivatives were characterized using FT-IR and 1H NMR. A series of hydroxypropyl guar derivatives with degrees of carboxymethylations ranging from 0.15-0.25 were modified with polyalkoxyalkyleneamines with molecular weights ranging from 300-3000. The ratio of oxypropylene to oxoethylene units in the polyalkoxyalkyleneamines was varied from 9/1 …


Nitrate Reduction And Methane Formation As Influenced By Iron-Centered Intermediate Redox Processes In Rice Soils, Bin Huang Jan 2005

Nitrate Reduction And Methane Formation As Influenced By Iron-Centered Intermediate Redox Processes In Rice Soils, Bin Huang

LSU Doctoral Dissertations

Rice fields are a major source of the greenhouse gases methane (CH4) and nitrous oxide (N2O) and contribute to nitrate (NO3-) pollution in waters. Ferric iron (Fe3+) and manganic manganese (Mn4+) are two intermediate alternative electron acceptors (AEAs) capable of regeneration in freshwater soils. In this investigation, the influences of iron-centered intermediate redox processes on NO3- reduction and CH4 formation in rice soils were studied using soil slurries, soil columns, and potted rice. Reduction of Fe3+-centered intermediate AEAs was mainly mediated by obligate anaerobes …


Stm And Arpes Studies Of Epitaxial Multilayer Ag On Cu(110) And Ni(110), Weichang Zhao Jan 2005

Stm And Arpes Studies Of Epitaxial Multilayer Ag On Cu(110) And Ni(110), Weichang Zhao

LSU Doctoral Dissertations

Ag nanostructures of multilayer coverages (< 30 monolayers) epitaxially self-assembled on Cu(110) and Ni(110) have been explored by scanning tunneling microscopy (STM), angle-resolved photoelectron emission spectroscopy (ARPES), and low energy electron diffraction (LEED). We have studied varied nanostructure morphologies self-assembled depending on different deposition/annealing processes and coverages, their atomic structures, growth behaviors and mechanisms, and the electronic structures of nanowires. At nominal coverages of 1.2 ML < ¦È < ~10 ML, there are two epitaxial structures on Cu(110) and Ni(110). One is a Ag(110) multilayer film, which has a superstructure with lateral periodic units of eight and three/four substrate lattice constants along [¯110] and along [001] respectively. Another is that of Ag(110) nanowires surrounded by pseudohexagonal Ag(111) monolayer. The Ag(110) nanowires are triangular in cross section. The two side surfaces are faceted and the long axis is atomically straight along [¯110]. Typical lengths are within the range of 100 ~ 5000 Å, widths 70 ~ 300 Å, side slopes 10 ~ 30º, and heights 5 ~ 60 Å. The Ag nanowires present extraordinary anisotropy with observed aspect ratios (length:width) of up to 20:1. The Ag(110) nanowires are in-registry with the substrate along [001], but not along [¯110]. At coverages of ~ 10 ML < ¦È < ~25 ML, there also exist two different nanostructures, the nanowires and a Ag(110) atomically-flat film with some pits as deep as down to the substrate and a one-dimensional quasiperiodic superstructure along [001]. There are two basic separations of the superstructural stripes: one is three lattices wide (~11 Å) and the other is two lattices wide (~7 Å). Both of nanostructures are stable at temperature up to at least 200 ¡ãC and not inter-transformable. The growth of the nanowires is driven by the elastic strain mechanism, but the growth of the atomically-flat film is driven by electronic growth mechanism originated from the electron quantum confinement in the vertical direction of the film. The ARPES of the nanowires shows dispersion in the vertical and the [¯110] directions, but no dispersion in the [001] direction because of the limited width (~ 200 Å).


The Asymptotic Z-Transform, Scott Jude Champagne Jan 2005

The Asymptotic Z-Transform, Scott Jude Champagne

LSU Master's Theses

Sequences of numbers and transformations from sequences to functions have been studied extensively, including the multiplication of two sequences through convolution and the equivalent multiplication of functions. The focal points of this thesis are the convolution field of causal sequences and their Z-transforms. Classically, the treatment of the Z-transform has been limited to those causal sequences for which the power series has a nontrivial radius of convergence. In this thesis it is shown that the Z-transform can be extended to all causal sequences without compromising any of the operational properties of the classical Z-transform.


Morphologic And Stratigraphic Evolution Of The Antarctic Peninsula, Pacific Margin, Jason Henry Holloman Jan 2005

Morphologic And Stratigraphic Evolution Of The Antarctic Peninsula, Pacific Margin, Jason Henry Holloman

LSU Master's Theses

Rebesco et al. (1998) proposed a general depositional model that relates sediment drift evolution on the Antarctic Peninsula Pacific-margin continental rise to glacial processes on the continental shelf. In their model, terrigenous sediment was directly delivered to the rise and contributed to the construction of large sediment drifts when grounded ice extended to the shelf edge. In this scenario, large volumes of fluidized sediment by-passed the margin at the mouth of ice streams (i.e., fast flowing ice), whereas prograding slopes were constructed on those portions of the shelf margin between major ice streams. This model relies heavily on the modern …


Detection And Evaluation Of Temperature Effects On Cell Proliferation In Somatic Tissues Of The Eastern Oyster, Crassostrea Virginica, By Flow Cytometry, Fernando Jimenez Jan 2005

Detection And Evaluation Of Temperature Effects On Cell Proliferation In Somatic Tissues Of The Eastern Oyster, Crassostrea Virginica, By Flow Cytometry, Fernando Jimenez

LSU Master's Theses

The goal of this thesis was to evaluate temperature effects on cell proliferation of eastern oyster somatic tissues for the development of an oyster cell line. Understanding the in vivo cell proliferation of an organism is essential for the development of cell culture. Cell proliferation can be measured by identifying nuclear cellular proteins involved in growth regulation and cellular transformation. The primary objectives of this study were to: 1) develop an assay to evaluate cell proliferation, 2) develop an assay to analyze nuclear RNA content, and 3) evaluate temperature effects on cell proliferation in somatic tissues. Proliferating cell nuclear antigen …


Effects Of Adding Sediment To A Fresh Water Thin Mat Floating Marsh, Kate Carpenter Jan 2005

Effects Of Adding Sediment To A Fresh Water Thin Mat Floating Marsh, Kate Carpenter

LSU Master's Theses

Floating marshes are wetlands of emergent vascular vegetation which have a significant mat of live and dead roots, decomposing and dead organic material, and mineral sediments. This mat moves vertically as ambient water levels rise and fall. These marshes have unique hydrology in that overland sheet flow is reduced or eliminated leaving no inorganic sediment input, but there is extensive belowground water exchange. The effect of significant sediment introduction into wetlands with floating marshes is unknown. The purpose of this study was to observe the marsh mat response to Mississippi River sediment addition and measure species composition change and growth …


Sensorsimulator: Simulation Framework For Sensor Networks, Cariappa D. Mallanda Jan 2005

Sensorsimulator: Simulation Framework For Sensor Networks, Cariappa D. Mallanda

LSU Master's Theses

Wireless sensor networks have the potential to become significant subsystems of engineering applications. Before relegating important and safety-critical tasks to such subsystems, it is necessary to understand the dynamic behavior of these subsystems in simulation environments. There is an urgent need to develop a simulation platform that is useful to explore both the networking issues and the distributed computing aspects of wireless sensor networks. Current approaches to simulating wireless sensor networks largely focus on the networking issues. These approaches use well-known network simulation tools that are often difficult to extend to explore distributed computing issues. Discrete-event simulation is a trusted …


Use Of Terraced Marsh Habitats By Estuarine Nekton In Southwestern Louisiana, Bryan Paul Gossman Jan 2005

Use Of Terraced Marsh Habitats By Estuarine Nekton In Southwestern Louisiana, Bryan Paul Gossman

LSU Master's Theses

A variety of techniques have been employed in attempts to mitigate the extensive wetland loss occurring in coastal Louisiana. Marsh terracing is a wetland restoration technique that has rapidly gained in popularity in recent years. Terraces are assumed to benefit coastal restoration by providing areas for emergent plant growth, reducing wave energies, and increasing edge habitat to support nekton communities. The objectives of this study were to: 1) determine the effect of marsh terraces on adjacent water quality and sediment characteristics, 2) compare nekton abundance, species richness, and diversity in edge and open water habitats within terraced and unterraced ponds, …


The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker Jan 2005

The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker

LSU Master's Theses

Elevated soluble aluminum concentrations can adversely affect plant growth. During a drought, wetland soils may experience higher than normal soluble aluminum due to the oxidation of metal sulfides and resulting decreases in pH, which mobilizes metallic cations. Louisiana coastal salt marshes were subject to a record-setting drought in the winter and spring of 2000 which was coincident with the die-off of large expanses of salt marsh, termed " brown marsh ". Spartina alterniflora was the primary plant species affected. However, because some individuals within large areas of die-off survived the brown marsh event, they may have been the more resistant …


Linear Versus Cyclic Inorganic/Organic Hybrid Oligomeric Molecules, Christopher Roland Sparrow Jan 2005

Linear Versus Cyclic Inorganic/Organic Hybrid Oligomeric Molecules, Christopher Roland Sparrow

LSU Master's Theses

The synthesis of the new aryl bis(β-diketone) ligand m-phenylenebis(acetylacetone) (m-pbaH2) allowed for complexation with copper(II) to form a 4-membered ring Cu4(m-pba)4. An alternate route, via a phospholene adduct, was implemented after difficulties in preparing the ligand via an azo sulfide conversion from m-phenylenediamine. The connection of two m-pba ligands coordinated to a Cu(II) metal ion causes a distortion along the axial position of the metal center. The pore has a diameter of (Cu-----Cu = 14.317 Å) when viewing opposite metal centers. An open coordination site along Cu(II) axial position may facilitate host-guest binding interactions. The concave shape of the host …


Nekton Utilization Of Black Mangrove (Avicennia Germinans) And Smooth Cordgrass (Spartina Alterniflora) Sites In Southwestern Caminada Bay, Louisiana, Melanie Christine Caudill Jan 2005

Nekton Utilization Of Black Mangrove (Avicennia Germinans) And Smooth Cordgrass (Spartina Alterniflora) Sites In Southwestern Caminada Bay, Louisiana, Melanie Christine Caudill

LSU Master's Theses

This is the first study to compare nekton use and habitat value among Spartina alterniflora (Spartina), Avicennia germinans (black mangrove), and transition (S. alterniflora and A. germinans) sites within Louisiana's salt marsh-mangrove ecotone. Fishes and crustaceans were collected in Caminada Bay during fall 2003 and spring 2004 using 4 m2, bottomless lift nets. Although analyses were unable to demonstrate significant differences in fish (p=0.0753) and crustacean (p=0.1457) densities and species composition (p=0.8801) across sites, habitat-specific trends in nekton use were evident. Fishes, including gulf killifish and sheepshead minnows, showed affinities for the Spartina site, while crustaceans, especially white shrimp, were …


Identifying Asphalt Construction As A Point Source Emitter Of Volatile Organic Compounds Near The Louisiana State University Ozone Monitoring Station, Sean Jason Kice Jan 2005

Identifying Asphalt Construction As A Point Source Emitter Of Volatile Organic Compounds Near The Louisiana State University Ozone Monitoring Station, Sean Jason Kice

LSU Master's Theses

The EPA has classified Baton Rouge as a non-attainment area for ozone pollution for many years. Since then Photochemical Assessment Monitoring Stations (PAMS) and other ozone monitoring stations around the metropolitan area have monitored for ozone, NOx, and more than 50 volatile organic compounds (VOCs) which are considered precursors to ozone pollution. Traditionally, automobile engines and industrial plants and refineries have been blamed as major point sources for VOC emissions and the ozone pollution they cause. This research focuses on another possible point source for failing ozone levels at one of the ozone monitoring stations located on the campus of …


Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman Jan 2005

Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman

LSU Master's Theses

A method was developed to simplify the approach to obtaining a better quantitative representation (QR) of complex clay mineral assemblages by XRD analysis. The method has eight steps: 1) preparation of samples with preferred orientation; 2) qualitative identification of phases; 3) peak decomposition to obtain precise locations of individual peaks contained within broad diffraction bands; 4) creation of a library of theoretical XRD patterns by modeling of one-dimensional XRD patterns; 5) selection of experimental library patterns; 6) employing the LINEST function found in common spreadsheet software to fit library patterns to experimental patterns; 7) evaluation of results to determine needed …


Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher Jan 2005

Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher

LSU Master's Theses

Euclid’s Elements is the foundation for geometry. Book V of Euclid’s Elements, which is independent from the earlier books, focuses on multiples, ratios, and proportions. This paper presents a model of the conceptual content of Book V, but using carefully selected modern notation to represent Euclid’s ideas without changing them drastically. All of the propositions and proofs from Euclid have been restated using just enough modern language to make clear for a modern reader. We also present a modern theory that bears analogy, proposition by proposition, to Euclid’s theory, but uses rigorous modern methods of proof.


Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov Jan 2005

Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov

LSU Master's Theses

The standard theory of the stochastic models used to value financial derivatives contracts involves models whose input parameters are deterministic functions and often constants. Because of the random nature of the changes in the market prices of the financial instruments, the coefficients of these models are inevitably susceptible to random perturbation from their initial estimates. In this paper we will investigate the behavior of some of the most widely used models when small changes are applied to their volatility component. Starting with the Black-Scholes model for the price of a European call option, we will continue our analysis of the …


Evaluation Of A Novel Method Of Predicting Estrogen Activity Of A Group Of Structurally Diverse Compounds, Daniel Consoer Jan 2005

Evaluation Of A Novel Method Of Predicting Estrogen Activity Of A Group Of Structurally Diverse Compounds, Daniel Consoer

LSU Master's Theses

The number of environmental chemicals found to have some level of endocrine activity has led to concern about the possible effects these compounds could have on human health and the health of other species, populations, and possibly whole ecosystems. The United States Environmental Protection Agency has been charged with testing a large number of these compounds, called endocrine-disrupting chemicals or hormonally active agents for hormonal activity. Limited testing resources have led to a call for alternate methods of screening, possibly for use in prioritizing this list to assist in efficient allocation of resources for further testing. This study describes a …


Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau Jan 2005

Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau

LSU Master's Theses

In response to increased annual wildfire destruction and insufficient wildfire mitigation approaches from the federal government, the state of California adopted Public Resources Code Sections 4290 and 4291 in the year 1991. These laws force the removal of fire-causing agents from public and private areas, and establish what is known as defensible space. Defensible space is defined in Section 4291 as the area within the perimeter of a parcel, development, neighborhood, or community where basic wildland fire protection practices and measures are implemented, providing the key point of defense from an approaching wildfire or escaping structure fire. One method to …


Visualization Based On Interactive Clipping: Application To Confocal Data, Gaurav Khanduja Jan 2005

Visualization Based On Interactive Clipping: Application To Confocal Data, Gaurav Khanduja

LSU Master's Theses

We have explored how clipping can be exploited in an interactive manner to visualize massive three-dimensional datasets. In essence, the proposed interactive clipping approach involves the dynamic adjustment of the clipping plane to expose any cross-section of the volume data and subsequent adjustment of the clipped surface to the best view position using a combination of rotation and translation. The thesis describes the design, implementation and application of our interactive-clipping-based visualization system. The implementation is done with OpenGL and C++, thus resulting in a highly portable and flexible system. For illustration, two types of scientific datasets, confocal data of a …


Associations Of Avian And Herpetofauna Communities With Forest Management At Multiple Spatial Scales, Holly Grace Legrand Jan 2005

Associations Of Avian And Herpetofauna Communities With Forest Management At Multiple Spatial Scales, Holly Grace Legrand

LSU Master's Theses

Decline of amphibians, reptiles, and numerous Neotropical migrant birds has been attributed to habitat destruction and alteration, which warrants examination of these groups in managed forests and their association with habitat characteristics at multiple spatial scales. We surveyed avifauna and herpetofauna communities in 3 managed forests in Louisiana during 2003-2004. Study areas included Sherburne Wildlife Management Area (WMA), a bottomland hardwood forest under uneven-aged management, Ben’s Creek WMA, an even-aged, short-rotation loblolly pine plantation, and Sandy Hollow WMA, a longleaf pine-savannah maintained with prescribed fire. Field techniques included surveys consisting of avian point counts, drift fence arrays (PFFT), cover boards, …