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Full-Text Articles in Physical Sciences and Mathematics

Influences On State-Level Policies For Wildfire Risk Reduction, Marios Anastasis Valiantis Jan 2003

Influences On State-Level Policies For Wildfire Risk Reduction, Marios Anastasis Valiantis

LSU Master's Theses

Wildland fires are part of the United State’s history and culture. The human dimension of State wildland fire management, - the relationship of people and wildland fire in America- is an important and driving force in how federal and state agencies respond to wildland fire, now and in the future. In many ways, the critical element for the management of wildland fire is the management of people, communities, and organizations. Explosive growth in the wildland-urban interface puts entire communities, their associated infrastructure and the socioeconomic fabric that holds communities together at a high risk from wildland fire. Year after year …


Using Functional Distance Measures When Calibrating Journey-To-Crime Distance Decay Algorithms, Joshua David Kent Jan 2003

Using Functional Distance Measures When Calibrating Journey-To-Crime Distance Decay Algorithms, Joshua David Kent

LSU Master's Theses

Spatial analysis has long been a valuable tool used within the criminal investigative process. This is especially true for serial offence cases where criminologists apply geographic profiling to model offender mobility and crime distribution patterns in order to estimate a criminal’s likely residence. Yet, traditional analytical methodologies have avoided the utilization of functional distance measures when modeling an offender’s journey-to-crime within an anisotropic landscape. By substituting straight-line Euclidean distances with travel path functional distance measures, the predictive utility and technological prerequisites associated with geographically profiling a localized serial offender was assessed using mathematically calibrated distance decay models. Both the travel-path …


Pulsed River Flooding Effects On Sediment Deposition In Breton Sound Estuary, Louisiana, Katherine Wheelock Jan 2003

Pulsed River Flooding Effects On Sediment Deposition In Breton Sound Estuary, Louisiana, Katherine Wheelock

LSU Master's Theses

Louisiana's deltaic coast is a dynamic sedimentary environment made vulnerable by Mississippi River channelization, which restricts freshwater, sediment, and nutrient inputs to adjacent estuaries. Freshwater diversions now reconnect some estuaries with historic fluvial sources, like Breton Sound basin, which receives Mississippi River suspended loads through the Caernarvon freshwater diversion. The project objectives were to quantify short-term sediment accumulation using sediment traps, evaluate sediment trap effectiveness, and compare long-term deposition using feldspar horizon markers and 210Pb dating to the annual sediment trap deposition. Magnitude and variations of sediment deposition at 14 sites were compared during an 18-month study in the upper …


Pcr Inhibition And Toxic Effects By Sediment Samples Exposed To Drilling Muds, Neal Gilpin Satterly Jan 2003

Pcr Inhibition And Toxic Effects By Sediment Samples Exposed To Drilling Muds, Neal Gilpin Satterly

LSU Master's Theses

This study evaluated the PCR inhibition and toxic effects by sediment samples exposed to drilling muds. This information was gathered in an attempt to identify what effect, if any, drilling muds had on the microbial community structure in sediments around four specific oil-drilling platforms in the Gulf of Mexico. Sediment samples were taken before and after drilling had taken place around two platforms (GB516 and VK916), and sediment samples were taken after drilling had taken place around two other platforms (MC292 and GB602). After using traditional, non-selective DNA extraction methods, successful amplification took place via PCR with all pre-drilling samples …


Development And Implementation Of Fine Structure Aerosol Spectrum Coagulation Kernels And Deposition Mechanisms Using Advanced Nodal Method In The Caerot Code, Hyeongkae Park Jan 2003

Development And Implementation Of Fine Structure Aerosol Spectrum Coagulation Kernels And Deposition Mechanisms Using Advanced Nodal Method In The Caerot Code, Hyeongkae Park

LSU Master's Theses

Aerosol transport in confined spaces was studied via numerical simulation using the dynamic aerosol equation, which is Boltzmann?s transport equation at the hydrodynamic limit. Until recent years, there existed no comprehensive computational tool to predict the spatial distribution and time evolution of aerosol size spectrum. A previously developed code, INDASOL3D, solves the dynamic aerosol equation by using a homogenized control-volume based finite difference method applying the group sectional method on the coagulation dynamics. However, quantitative correctness has not been satisfactory. In this thesis, two new codes (SAEROSA, and CAEROT) were developed. SAEROSA computes the time evolution of the size spectrum …


A Comparison Of Finfish Assemblages On Subtidal Oyster Shell (Cultched Oyster Lease) And Mud Bottom In Barataria Bay, Louisiana, John Plunket Jan 2003

A Comparison Of Finfish Assemblages On Subtidal Oyster Shell (Cultched Oyster Lease) And Mud Bottom In Barataria Bay, Louisiana, John Plunket

LSU Master's Theses

Recent research suggests that oyster reefs provide unique three-dimensional hard bottom habitat for many fish species. Along the northern shore of the Gulf of Mexico, oyster shell bottoms are predominantly flat, subtidal and cultched, lacking the vertical relief and spatial heterogeneity provided by natural reefs. This study compared finfish assemblages, gut contents, and macroinvertebrate assemblages at subtidal oyster shell (cultched oyster lease) and mud bottoms in Barataria Bay, Louisiana. Three mud and three shell sites were sampled on seven dates from October 2001 to October 2002, using gill nets and substrate trays. Data from the gill nets were used to …


Regional Water Quality Models For The Prediction Of Eutrophication Endpoints, Anindita Das Jan 2003

Regional Water Quality Models For The Prediction Of Eutrophication Endpoints, Anindita Das

LSU Master's Theses

Eutrophication is a process by which a waterbody progresses from its origin to its extinction. During this period, there is a gradual accumulation of nutrients and organic biomass, accompanied by a decrease in average depth of the water due to sediment accumulation, and an increase in primary productivity, usually in the form of dense algal blooms. Cultural eutrophication occurs when humans, through their various activities, greatly accelerate this process. Eutrophication can cause loss in species diversity, fish kills, and decrease the aesthetic value of a waterbody. The EPA is trying to prevent cultural eutrophication by setting standards for water quality …


Stock Price Modeling And Insider Trading Theory, Jessica J. Guillory Jan 2003

Stock Price Modeling And Insider Trading Theory, Jessica J. Guillory

LSU Master's Theses

The mathematical study of stock price modeling using Brownian motion and stochastic calculus is a relatively new field. The randomness of financial markets, geometric brownian motions, martingale theory, Ito's lemma, enlarged filtrations, and Girsanov's theorem provided the motivation for a simple characterization of the concepts of stock price modeling. This work presents the theory of stochastic calculus and its use in the financial market. The problems on which we focus are the models of an investor's portfolio of stocks with and without the possibility of insider trading, opportunities for fair pricing of an option, enlarged filtrations, consumptions, and admissibility. This …


Gauss' Method Of Least Squares: An Historically-Based Introduction, Belinda B. Brand Jan 2003

Gauss' Method Of Least Squares: An Historically-Based Introduction, Belinda B. Brand

LSU Master's Theses

This work presents Gauss' justification of the method of least squares, following the treatment given by Gauss himself in "Theoria Combinationis Observationum Erroribus Minimis Obnoxiae," where the main idea is to show that the least squares estimate is the unbiased linear estimate of minimum variance. (Actually, we present Gauss' argument both in his terminology and translated into matrix terminology.) We show how this contrasts with Gauss' earlier justfication in "Theoria Motus Corporum Coelestium" which was based on the assumption of a normal distribution of errors, and yielded the estimate of maximum likelihood. We present as a background the development from …


Multileaf Collimator Positional Reproducibility Evaluated With A Two-Dimensional Diode Array, Kara King Ferachi Jan 2003

Multileaf Collimator Positional Reproducibility Evaluated With A Two-Dimensional Diode Array, Kara King Ferachi

LSU Master's Theses

When delivering the total dose via a sequence of small fields shaped by a multileaf collimator, it is important to consider leaf positional reproducibility. A small error in the leaf position can result in large dose errors to the entire field. This is true for both dynamic multileaf collimation and step and shoot delivery. The goal of this research project is to design a method of quality assurance that is easily reproducible, sensitive to small changes in leaf position, and requires minimal time on the part of the medical physicist to carry out. This paper describes a system of measurements …


A Stellar Parameter Calibration Of Iue Data For The Determination Of The Present Day Mass Function Of High Mass Stars, Kenneth Thomas Taylor Jan 2003

A Stellar Parameter Calibration Of Iue Data For The Determination Of The Present Day Mass Function Of High Mass Stars, Kenneth Thomas Taylor

LSU Master's Theses

A study of stellar atmosphere models and the photometric quantity R is presented here, with R being the ratio of the integrated de-reddened fluxes from the two wavelength regions of the International Ultraviolet Explorer (IUE) satellite cameras. The effective temperatures and surface gravities of the stellar atmospheres were calibrated against R and absolute magnitude, using stellar evolution tracks from the literature, and applied to over 156 LMC stars whose masses and mass function are then derived from the results. The results show that the effective temperatures and surface gravities of stars derived from R and absolute magnitude correlate well with …


The Effects Of Sediment Grain Size And Oil Exploration On Microbial Atp Biomass, Eric Tyson Guilbeau Jan 2003

The Effects Of Sediment Grain Size And Oil Exploration On Microbial Atp Biomass, Eric Tyson Guilbeau

LSU Master's Theses

Adenosine triphosphate (ATP) is a unique biochemical indicator of active microbial biomass and its relationship to environmental conditions. Its assay in sediments is complicated, however, by adsorptive loss to the sediment matrix and subsequent interferences in the luciferin-luciferase assay by compounds released during the extraction process. Corrections must be applied to correct for these losses and we describe a novel approach using radioactive ATP to correct for ATP adsorption. The sediment matrix also plays a significant role in determining both the magnitude of the ATP pool and the extent of the ATP adsorptive loss. Coarser sediments were found to have …


Swimming Performance Of Juvenile Florida Pompano (Trachinotus Carolinus) And Atlantic Spadefish (Chaetodipterus Faber) Exposed To Sublethal Concentrations Of Ethylene Glycol And Methanol: Individual And Synergistic Effects, Mark Alan Stead Jan 2003

Swimming Performance Of Juvenile Florida Pompano (Trachinotus Carolinus) And Atlantic Spadefish (Chaetodipterus Faber) Exposed To Sublethal Concentrations Of Ethylene Glycol And Methanol: Individual And Synergistic Effects, Mark Alan Stead

LSU Master's Theses

Recently, new technology has pushed petrochemical exploration into increasingly deeper water (>305 m) at increased risks to marine fauna. One risk is from chemical additives used to enhance deepwater production such as ethylene glycol and methanol which are used during the production and treatment to prevent the formation of gas hydrates in deepwater wells and pipelines. Juvenile Florida pompano (Trachinotus carolinus) were used in controlled experiments to test the effects of 3.0 % ethylene glycol (EG), 1.07 % methanol (MeOH) and a combination of the two chemicals(EG + MeOH) on swimming performance of individual fish. Swimming performance was evaluated …


Effect Of Temperature On Efficiency Of In Situ Bioremediation Technology: A Laboratory Microcosm And Field Study, Javed Iqbal Jan 2003

Effect Of Temperature On Efficiency Of In Situ Bioremediation Technology: A Laboratory Microcosm And Field Study, Javed Iqbal

LSU Master's Theses

Laboratory microcosm experiment and parallel ex situ bioremediation studies were conducted to study the effect of temperature on in situ bioremediation systems installed at Superfund site in southeast Georgia. Laboratory microcosms, inoculated with PAHs/phenols specific microorganisms, at high temperatures (42±2°C; 107±3°F) demonstrated a significant reduction of residual polycyclic aromatic hydrocarbons (PAHs) and selected phenols from 4927±1356ng/g dry weight soil to 1158±530ng/g with a kinetic rate of 76.1±16.8ng/g/day (84% reduction; p≤0.01) in 49days. High temperature non-inoculated microcosms were reduced of residual PAHs and phenols from 1117±436ng/g to 341±116ng/g with a kinetic rate of 15.8±6.5ng/g/day (65% reduction; p≤0.01) in 49days. Low temperature …


Compositional Systematics Of Deep, Low Salinity Formation Waters In The Upper Wilcox Of Southeastern Texas, Kathleen (Kt) Moran Jan 2003

Compositional Systematics Of Deep, Low Salinity Formation Waters In The Upper Wilcox Of Southeastern Texas, Kathleen (Kt) Moran

LSU Master's Theses

Overpressured Eocene Wilcox sandstones in the Newton County, Texas Sabine Tram field contain water with salinities ranging from 14 to 28 g/L. The solutes appear to fall loosely into three groups. Na, Ca, and Mg follow systematics previously known globally for saline formation waters whereby their concentrations are controlled by fluid-mineral equilibrium. Cl, Br, I, and B are conservatively diluted constituents of some saline endmember that is not solely connate marine. Potassium does not follow any known basinal systematic, and the formation water is supersaturated with respect to SiO2 by an order of magnitude. Meteoric water is not a probable …


Scalable Parallel Molecular Dynamics Algorithms For Organic Systems, Satyavani Vemparala Jan 2003

Scalable Parallel Molecular Dynamics Algorithms For Organic Systems, Satyavani Vemparala

LSU Master's Theses

A scalable parallel algorithm, Macro-Molecular Dynamics (MMD), has been developed for large-scale molecular dynamics simulations of organic macromolecules, based on space-time multi-resolution techniques and dynamic management of distributed lists. The algorithm also includes the calculation of long range forces using Fast Multipole Method (FMM). FMM is based on the octree data structure, in which each parent cell is divided into 8 child cells and this division continues until the cell size is equal to the non-bonded interaction cutoff length. Due to constant number of operations performed at each stage of the octree, the FMM algorithm scales as O(N). Design and …


Computer Assisted Eye Fungal Infection Diagnosis, Madhusudhanan Balasubramanian Jan 2003

Computer Assisted Eye Fungal Infection Diagnosis, Madhusudhanan Balasubramanian

LSU Master's Theses

In this thesis, an attempt has been made to assist the diagnosis of Fungal Keratitis, a fungal infection that occurs in the corneal layers of the eye, by identifying the region of infection in the corneal images using fractal-based features. Three features related to the fractal dimension of the surface of the image, when represented in a 3D using the pixel intensity measure, are used to identify these regions in the image. To reduce the computation complexity, Fisher linear discriminant (FLD) is used to reduce the 3D raw feature to 1D feature, while preserving feature values. Using the adaptive mixtures …


Factors Affecting Participation In City Recycling Programs, Stacy Marie Lockhart Jan 2003

Factors Affecting Participation In City Recycling Programs, Stacy Marie Lockhart

LSU Master's Theses

Recycling consists of diverting or recovering materials from the solid waste stream that would otherwise end up returning to the environment as a potential source of pollution. These collected materials are then used as raw materials in the manufacture or assembly of a new product or package. Over the years the amount of municipal solid waste being generated per person has steadily increased. Waste disposal costs are also increasing, making recycling even more important. To address this issue cities are developing recycling policies or plans. The type of plan varies according to the area; as of this time there are …


Field Validation Of Bentazon Phytoremediation, Sajida Begum Jan 2003

Field Validation Of Bentazon Phytoremediation, Sajida Begum

LSU Master's Theses

Phytoremediation with black willow (Salix nigra) was conducted in 1996 by planting trees at a density of 2000 trees/hectare at BASF Corporation in a shallow groundwater plume containing low levels of bentazon. In this project, the roots, stems,and leaves of the black willow plants were extracted and analyzed to see if bentazon from the ground water was taken up by the plants. Different extraction procedures such as liquid-phase extraction and solid-phase extraction were compared. Final determination using different analytical techniques such as GC-MSD, GC-ECD, and HPLC with UV detection for the isolation and analysis of bentazon residues from the plant …


Quantifying Habitat Quality Of Larval Bay Anchovy (Anchoa Mitchilli) In Chesapeake Bay By Linking An Individual-Based Model With Spatially-Detailed Field Data, Aaron Thomas Adamack Jan 2003

Quantifying Habitat Quality Of Larval Bay Anchovy (Anchoa Mitchilli) In Chesapeake Bay By Linking An Individual-Based Model With Spatially-Detailed Field Data, Aaron Thomas Adamack

LSU Master's Theses

Larval bay anchovy (Anchoa mitchilli) habitat quality in Chesapeake Bay was predicted using an individual-based model applied to spatially-detailed field data from Rilling and Houde (1999). Habitat quality was predicted using the ratio of instantaneous mortality rate to instantaneous growth rate. Model predictions of habitat quality were compared to field estimates of habitat quality derived from the spatially-detailed field data. Three sets of one-day simulations were performed to estimate larval growth and mortality rates throughout Chesapeake Bay during June and during July 1993. Field-based simulations used field data to estimate the model inputs of water temperature, zooplankton densities, and the …


Middle Miocene Grounding Events On The Ross Sea Outer Continental Shelf, Antarctica, Juan Manuel Chow Jan 2003

Middle Miocene Grounding Events On The Ross Sea Outer Continental Shelf, Antarctica, Juan Manuel Chow

LSU Master's Theses

The middle Miocene δ18O enrichments from deep-sea data and eustatic sea level falls are traditionally attributed to expansion of the East Antarctic Ice Sheet. Interpretations of such data have led many to conclude that the West Antarctic Ice Sheet (WAIS) was not well-developed until the late Miocene. In such a scenario, middle Miocene glaciation on the Ross Sea shelf would have had to be minimal, perhaps in the form of ice caps, to be consistent with proxy data. New seismic-stratigraphic analysis of the Ross Sea outer continental shelf suggests that at least five grounding events (ice sheet advances …


A Parametrization Approach For Solving The Hamilton-Jacobi-Equation And Application To The A2 Toda Lattice, Mohammad Dikko Aliyu Jan 2003

A Parametrization Approach For Solving The Hamilton-Jacobi-Equation And Application To The A2 Toda Lattice, Mohammad Dikko Aliyu

LSU Master's Theses

Hamilton-Jacobi (HJ)-theory is an extension of Lagrangian mechanics and concerns itself with a directed search for a coordinate transformation in which the equations of motion can be easily integrated. The equations of motion of a given mechanical system can often be simplified considerably by a suitable transformation of variables such that all the new position and momemtum coordinates are constants. A particular type of transformation is chosen in such a way that the new equations of motion retain the same form as in the former coordinates; such a transformation is called canonical or contact and can greatly simplify the solution …


An Investigation Of A Salt-Dome Environment At South Timbalier 54, Gulf Of Mexico, Robert E. Little, Jr Jan 2003

An Investigation Of A Salt-Dome Environment At South Timbalier 54, Gulf Of Mexico, Robert E. Little, Jr

LSU Master's Theses

Salt domes have been studied in the Gulf Coast region to look at how, why, and where saline waters are located within these field areas. Fluid flow model and pathway studies can be helpful to the research of saline water migration because it can be correlated to hydrocarbon migration in petroleum exploration. The South Timbalier 54 field occurs over a salt dome that sits at approximately 3,048 meters beneath the seafloor. Two major faults were found originating from the salt dome up into the shallow section of the field. The sands were deposited in fluvial, deltaic, or marine environments. The …


Evaluation Of The Profiler As A Tool For Imrt Qa, Manuel Rodriguez Jan 2003

Evaluation Of The Profiler As A Tool For Imrt Qa, Manuel Rodriguez

LSU Master's Theses

The principal goal in this project is to determine if a one-dimensional diode array, the Profiler (Sun Nuclear Corporation), can be used as a tool for intensity modulated radiation therapy quality assurance (QA). A one-dimensional diode array can be used to measure dose and dose profiles for IMRT fields. IMRT fields for real cases at Mary Bird Perkins Cancer Center were used to test the Profiler model 1170 (Sun Nuclear Corporation). The main concern with the Profiler is that there is not central diode in the array. The absorbed dose displayed in the Profiler window is the average of the …


Correlation Of Core Characteristics To Outcrop Upper Jackfork Group Turbidites, Degray Lake, Arkansas, Daniel James Golob Jan 2003

Correlation Of Core Characteristics To Outcrop Upper Jackfork Group Turbidites, Degray Lake, Arkansas, Daniel James Golob

LSU Master's Theses

Pennsylvanian age Jackfork Group cores from the DeGray Lake Dam and outcrop from the east wall of the DeGray Lake Spillway, Arkansas, provide an opportunity for a detailed study on the transport and depositional characteristics of a fine-grained, deep-water depositional system. Two phases of resedimentation processes are responsible for deposition of the sediments in the cores and the outcrop. Primary resedimentation processes transport terrigenous sediments from the shelf or basin edge into the middle fan environment, while secondary resedimentation alter the sediments after they are initially deposited in the environment. Debris flows, slurry flows, and high and low density turbidity …


Toward A Sustainable Energy Future?: A Comparison Between U.S. And European Energy Sectors, Annett Moehner Jan 2003

Toward A Sustainable Energy Future?: A Comparison Between U.S. And European Energy Sectors, Annett Moehner

LSU Master's Theses

Since 1987, the concept of sustainable development, which tries to combine economic, social and environmental concerns into one benign development model, has become increasingly popular worldwide. To explore and explain the differences in accomplishing sustainable development, this thesis looks at one specific aspect: the energy sectors in the United States and the European Union. After giving an overview on the political and theoretical aspects of sustainable development, the various sustainability dimensions in the energy sector are explored. The following four reasons which warrant the change of the current fossil fuel intense energy sector are discussed: first, air pollution; second, insecurity …


A Risk-Averse Strategy For Blackjack Using Fractional Dynamic Programming, Ryan A. Dutsch Jan 2003

A Risk-Averse Strategy For Blackjack Using Fractional Dynamic Programming, Ryan A. Dutsch

LSU Master's Theses

We present how blackjack is related to a discrete-time control problem, rather than a zero-sum game. Using the compiler Visual C++, we write a program for a strategy for blackjack, but instead of maximizing the expected value, we use a risk-averse approach. We briefly describe how this risk-averse strategy is solved by using a special type of dynamic programming called fractional dynamic programming.


Low Salinity Waters In Deep Sedimentary Basins, David Scott Szalkowski Jan 2003

Low Salinity Waters In Deep Sedimentary Basins, David Scott Szalkowski

LSU Master's Theses

While the composition and origin of brines in deep sedimentary basins has been extensively discussed, the composition and origin of low salinity waters is not as well documented. Since the 1960s, the presence of deep, low-salinity waters has been observed in some sedimentary basins and is commonly present in overpressured sections. The episodic release of low salinity, overpressured fluids upward into sediments containing high salinity formation waters likely occurs at <100-year intervals. Because there is a growing body of evidence that suggests mixing formation waters of varying salinity could induce the dissolution and precipitation of minerals, it is important to have detailed information about chemical compositions of both end-member fluids to adequately predict such mixing results. This study concludes that low salinity waters (<35 g/l) are generally not unique in major solute composition when compared to high salinity waters (>35 g/l). On log-log plots, monovalent cations plot along 1:1 slopes with respect to salinity and total anionic charge, while divalent cations plot along 2:1 slopes. However, this study concludes …


The Use Of The Bang-3 Polymer Gel To Quantify The Three-Dimensional Dose Distribution Of Imrt, Paul Anthony Bruce Jan 2003

The Use Of The Bang-3 Polymer Gel To Quantify The Three-Dimensional Dose Distribution Of Imrt, Paul Anthony Bruce

LSU Master's Theses

The sophistication of radiation therapy delivery techniques at Mary Bird Perkins Cancer Center (MBPCC) creates the need for an advanced dosimetric system that can quantify and verify the dose distributions in three-dimensions. Current dosimetric systems perform this dose analysis in only one or two dimensions. This paper evaluates the application of BANG-3™ polymer gel dosimetry to quantify the 3-D dose distribution of Intensity-Modulated Radiation Therapy (IMRT) using a "step and shoot" approach. The gel was irradiated by 10 MV photons at a dose rate of 400 MU/min. Relaxation rate maps were computed from proton density and T2-weighted magnetic …


Comparative Analysis Of State Environmental Enforcement In Region Six Of The United States, Rebecca Marcus Jan 2003

Comparative Analysis Of State Environmental Enforcement In Region Six Of The United States, Rebecca Marcus

LSU Master's Theses

Through intense studies of agency audits, EPA policies and documents, state environmental compliance data and state agency issued documents, I have evaluated the enforcement programs of Region Six state environmental agencies. The four elements utilized to perform this evaluation were listed in EPA compliance assurance program documents. The analysis was conducted by comparing state program performance in each element. Element 1 is the “appropriate identification of violations.” Element 2 is the “timely issuance of enforcement actions.” Element 3 is the “escalation of enforcement actions when violations continue.” Element 4 is the “ability to assess and collect penalties.” These elements are …