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Full-Text Articles in Physical Sciences and Mathematics

Tower Families Of Ribbon Graphs, Jordan Keller May 2012

Tower Families Of Ribbon Graphs, Jordan Keller

Honors Theses

No abstract provided.


Time Dependence Of Bathymetric Effects On Hurricane Storm Surge, Christopher Dupuis May 2012

Time Dependence Of Bathymetric Effects On Hurricane Storm Surge, Christopher Dupuis

Honors Theses

No abstract provided.


Code . Art: Code With An Art File Extension, Cole Wiley Apr 2012

Code . Art: Code With An Art File Extension, Cole Wiley

Honors Theses

No abstract provided.


Synthesis And Cellular Investigations Of The 131-Lysyl Derivative Of Chlorin E6, Stewart Wynn Humble Apr 2012

Synthesis And Cellular Investigations Of The 131-Lysyl Derivative Of Chlorin E6, Stewart Wynn Humble

Honors Theses

No abstract provided.


A Study Of Pixelated Cdznte Detector Setups For Future 0Νββ Decay Searches, Alexander Leder Apr 2012

A Study Of Pixelated Cdznte Detector Setups For Future 0Νββ Decay Searches, Alexander Leder

Honors Theses

No abstract provided.


Phase Estimation With Two-Mode Squeezed Vacuum And Parity Detection: Bayesian Analysis, Keith Motes Jan 2012

Phase Estimation With Two-Mode Squeezed Vacuum And Parity Detection: Bayesian Analysis, Keith Motes

Honors Theses

No abstract provided.


Excluded Minors For Apex Classes Of Graphs, Christine A. Derbins Jan 2012

Excluded Minors For Apex Classes Of Graphs, Christine A. Derbins

Honors Theses

No abstract provided.


Some Tracking Problems For Aerospace Models With Input Constraints, Aleksandra Gruszka Jan 2012

Some Tracking Problems For Aerospace Models With Input Constraints, Aleksandra Gruszka

LSU Doctoral Dissertations

We study tracking controller design problems for key models of planar vertical takeoff and landing (PVTOL) aircraft and unmanned air vehicles (UAVs). The novelty of our PVTOL work is the global boundedness of our controllers in the decoupled coordinates, the positive uniform lower bound on the thrust controller, the applicability of our work to cases where the velocity measurements may not be available, the uniform global asymptotic stability and uniform local exponential stability of our closed loop tracking dynamics, the generality of our class of trackable reference trajectories, and the input-to-state stability of the controller performance under actuator errors of …


Evaluation Of Growth Rates And Establishment Patterns Of Water-Elm (Planera Aquatica) And Baldcypress (Taxodium Distichum) In Response To Hydrologic And Climatic Conditions At Catahoula Lake, Louisiana, Sanjeev Joshi Jan 2012

Evaluation Of Growth Rates And Establishment Patterns Of Water-Elm (Planera Aquatica) And Baldcypress (Taxodium Distichum) In Response To Hydrologic And Climatic Conditions At Catahoula Lake, Louisiana, Sanjeev Joshi

LSU Master's Theses

Hydrologic alterations frequently lead to vegetation changes in floodplain ecosystems. In Louisiana, there has been an expansion of water-elm (Planera aquatica) and to a lesser extent baldcypress (Taxodium distichum) at Catahoula Lake, a Ramsar Wetland of International Importance. Water-elm and baldcypress both are flood tolerant species; baldcypress growth is known to be influenced by hydrologic conditions more than climate. The expansion of these woody trees has reduced herbaceous vegetation valuable for waterfowl. In this study, I tested two hypotheses that establishment of water-elm trees into the lake increased after the construction of water control structures in the nearby Black River …


Habitat- And Region-Specific Reproductive Biology Of Female Red Snapper (Lutjanus Campechanus) In The Gulf Of Mexico, Dannielle Helen Kulaw Jan 2012

Habitat- And Region-Specific Reproductive Biology Of Female Red Snapper (Lutjanus Campechanus) In The Gulf Of Mexico, Dannielle Helen Kulaw

LSU Master's Theses

This study compares reproductive biology estimates of female red snapper among three habitat types (natural shelf-edge banks, standing petroleum platforms and toppled petroleum platforms) and among six regions in the Gulf of Mexico (central Florida, northwest Florida, Alabama, Louisiana, north Texas and south Texas). In both studies, batch fecundity and spawning frequency increased with length, weight and age, and batch fecundity was best correlated with maternal length. Gulf-wide, 75% maturity was achieved by age-3 and 100% maturity was reached by age-8. Sizes- and ages-at-maturity differed among habitat types and regions. Females from natural habitat reached 50% maturity the slowest (age-5, …


Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff Jan 2012

Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff

LSU Master's Theses

There is evidence that significant reductions (about 50%) in surface water nitrate concentrations within coastal deltaic wetlands receiving diverted Mississippi River water can be contributed to denitrification. Yet there is also contrasting evidence that other processes could be responsible for this nitrate reduction. As Louisiana plans the implementation of major Mississippi River sediment diversions, a thorough understanding of nitrogen dynamics is necessary to reduce risks of coastal eutrophication and offshore hypoxia. A mechanistic numerical computer model has been developed to simulate nitrogen biogeochemistry within the wetlands of the prograding Wax Lake Delta. This model is calibrated to observed fluxes within …


Spatial Variation Analysis Of Salinity To Determine Fluid Flow Pathways And Reservoir Compartmentalization In A Deepwater Gulf Of Mexico Field, William Jacob Daugherty Jan 2012

Spatial Variation Analysis Of Salinity To Determine Fluid Flow Pathways And Reservoir Compartmentalization In A Deepwater Gulf Of Mexico Field, William Jacob Daugherty

LSU Master's Theses

Variations in salinity have been documented in previous studies onshore Louisiana in the Wilcox group (Funayama and Hanor 1995) as well as offshore Louisiana on the continental shelf (Bruno and Hanor 2003 and Steen et al. 2011). These studies were conducted using various methods to estimate pore water salinity and make inferences about possible fluid flow pathways and compartmentalization of reservoirs in order to better understand the complex hydrogeology of the Gulf of Mexico. Similar variations in salinity were documented in this study located in a deepwater salt withdrawal minibasin located on the upper slope of the Gulf of Mexico. …


An Evaluation Of Alternative Approaches For Simulating Animal Movement In Spatially-Explicit Individual-Based Models, Katherine Shepard Watkins Jan 2012

An Evaluation Of Alternative Approaches For Simulating Animal Movement In Spatially-Explicit Individual-Based Models, Katherine Shepard Watkins

LSU Doctoral Dissertations

Simulating animal movement in spatially-explicit individual-based models (IBMs) is both challenging and critically important to accurately estimating population dynamics. I compared four distinct movement approaches or sub-models (restricted-area search, kinesis, event-based, and run and tumble) in a series of simulation experiments. I used an IBM loosely based on a small pelagic fish that simulated growth, mortality, and movement of a cohort on a 2-dimensional grid. First, I tested the sub-models calibrated (i.e., trained) with a genetic algorithm in one set of environmental conditions in three other novel environments. The sub-models performed well, except restricted-area search and event-based that needed to …


Do Learning Logs Have An Impact On The Conceptual Mastery Of Force And Motion?: Subtitle, John Arthur Underwood Jan 2012

Do Learning Logs Have An Impact On The Conceptual Mastery Of Force And Motion?: Subtitle, John Arthur Underwood

LSU Master's Theses

This two-week study was conducted to investigate the impact Learning Logs have on student conceptual mastery of force, motion, and kinematics. To begin the study a sample of 554 ninth grade students were selected from a suburban public school in Louisiana. The students were randomly divided into experimental and control groups within four teachers’ classrooms. This distribution was to examine the impact of Learning Logs regardless of the teaching style or time of day. Upon the study’s conclusion there was no significant differences noted due to teaching style or time of day. The Force Motion Concept Evaluation (FMCE) was used …


What Does The ¹⁴C Method For Estimating Photosynthetic Rates In The Ocean Really Measure?, Shaofeng Pei Jan 2012

What Does The ¹⁴C Method For Estimating Photosynthetic Rates In The Ocean Really Measure?, Shaofeng Pei

LSU Doctoral Dissertations

The 14C method has been used extensively by both limnologists and oceanographers to measure photosynthetic rates in aquatic systems, and the large database of 14C measurements that now exists is the ground truth with which satellite algorithms for estimating marine photosynthetic rates on a basin and global scale have been calibrated. However, disconcerting uncertainties still remain with respect to whether and under what circumstances the 14C method provides an estimate of net or gross photosynthesis, or something in between. My study combined batch and continuous culture studies to clarify this ambiguous issue. The batch culture work with …


Water Quality Dynamics Of Low-Gradient, Headwater Streams In A Timber-Industry Dominated Watershed In Louisiana, Abram Atys Dasilva Jan 2012

Water Quality Dynamics Of Low-Gradient, Headwater Streams In A Timber-Industry Dominated Watershed In Louisiana, Abram Atys Dasilva

LSU Master's Theses

Timber harvesting can degrade the quality of adjacent water bodies, an important concern for Louisiana, nearly 50% of which is forested, and in which the forest industry is the second-largest manufacturing employer. To protect valuable freshwater resources in Louisiana, a manual of best management practices (BMPs) was published in 2000 describing techniques for limiting forestry-caused water quality degradation. While these BMPs are widely implemented, their effectiveness in protecting water quality is largely unknown. To determine the effectiveness of these BMPs, this thesis research conducted three studies to address timber harvest BMP effectiveness on protection of stream dissolved oxygen, metabolism, and …


Thermal And Pore Pressure History Of The Haynesville Shale In North Louisiana: A Numerical Study Of Hydrocarbon Generation, Overpressure, And Natural Hydraulic Fractures, William C. Torsch Jan 2012

Thermal And Pore Pressure History Of The Haynesville Shale In North Louisiana: A Numerical Study Of Hydrocarbon Generation, Overpressure, And Natural Hydraulic Fractures, William C. Torsch

LSU Master's Theses

New drilling technology has led to a revival of drilling in mature petroleum basins such as the Haynesville Formation in east Texas and north Louisiana. In north Louisiana, the Upper Jurassic (Kimmeridgian) aged Haynesville shale has a basinward SW dip and is located at depths ranging from around 10,500 ft to the northeast and 14,000 ft to the southwest with local minimums at the Sabine and Monroe Uplifts. Formation thickness ranges from 100 to 400 feet. Prolific natural gas production is attributed to relatively high average porosity (8 to 14%) and a high geopressure gradient > 0.9 psi/ft. (Wang and Hammes, …


Proton Dose Calculations In Homogeneous Media, John Wesley Chapman, Jr. Jan 2012

Proton Dose Calculations In Homogeneous Media, John Wesley Chapman, Jr.

LSU Master's Theses

In this study, a proton pencil beam dose calculation algorithm was developed for a parallel, monoenergetic beam incident on a homogeneous water phantom. Fermi-Eyges theory (Eyges 1948) was used to transport pencil beams, and the characteristic width of elastic scatter events was modeled using the differential Moliere scattering power (Gottschalk 2010). The incorporation of this scattering power formalism allowed our model to account for multiple Coulomb scattering, single scattering, plural scattering, and rigorously accounted for material effects on scatter. Nonelastic nuclear interactions were incorporated into an additional pencil beam model. The attenuation of primary fluence due to nuclear events was …


Ionic Materials For Applications In Sensing And Optoelectronics, Sergio L. De Rooy Jan 2012

Ionic Materials For Applications In Sensing And Optoelectronics, Sergio L. De Rooy

LSU Doctoral Dissertations

Organic salts consist of bulky anions and/or cations whose properties can be tailored for specific purposes. Ionic liquids (ILs) are (semi)organic salts with melting points below 100 ºC. They typically exhibit neglible vapor pressures, high thermal stability, wide liquidus range, and tunable solubility. Moreover specific functions can be built into their respective ions. The first part of the dissertation involves discussions of chiral ionic liquids with additional protic, magnetic, and magneto-luminescent properties, respectively. In addition to their enantioselective sensing capabilities, the ILs may find use in chiral separations and catalysis. The second part of the dissertation involves discussions of fluorescent …


U-Pb Geochronology Of Detrital Zircon In Quartzites Of The Sawtooth Metamorphic Complex, Sawtooth Range, Idaho, Usa, Philip Gerard Bergeron Jan 2012

U-Pb Geochronology Of Detrital Zircon In Quartzites Of The Sawtooth Metamorphic Complex, Sawtooth Range, Idaho, Usa, Philip Gerard Bergeron

LSU Master's Theses

In southwest Laurentia, the Paleoproterozoic Selway terrane has been proposed to extend as basement from the Wyoming Province to the Proterozoic rifted margin of Laurentia primarily based on limited exposures. The Sawtooth Metamorphic Complex (SMC), Idaho, a series of high-grade metasupracrustal rocks lies within the proposed region of the Selway terrane and may represent remnants of this terrane. Alternatively, it may represent another basement terrane of cratonic North America. To test the hypothesis that the SMC belongs to the Selway terrane, detrital zircon U/Pb ages of five quartzite samples were analyzed by LA-ICP-MS to establish age, possible provenance, and age …


Pretesting In Science: Effect On Unit Test Scores, Mary Catherine Johnson Jan 2012

Pretesting In Science: Effect On Unit Test Scores, Mary Catherine Johnson

LSU Master's Theses

ABSTRACT This study examines the effect that pretesting has on unit test scores in a high school Biology I classroom. The experimental classes were given a pretest before four units of curriculum and then taught the concepts of these units with a traditional lecture based methodology. Their unit test scores were compared to a control class that did not take pretests before the units. In addition, the End of Course (EOC) test scores of the control and experimental classes were compared to determine if pretesting improved transfer of knowledge to a different type of test. Pretesting did not cause a …


Ecology Of Rusty Blackbirds Wintering In Louisiana: Seasonal Trends, Flock Composition And Habitat Associations, Emma Elizabeth Deleon Jan 2012

Ecology Of Rusty Blackbirds Wintering In Louisiana: Seasonal Trends, Flock Composition And Habitat Associations, Emma Elizabeth Deleon

LSU Master's Theses

With an estimated population loss of at least 5% annually and a 100-year history of decline, Rusty Blackbirds (Euphagus carolinus) are one of the fastest declining bird species in North America. Determining cause of decline is important, both for conserving the species and for identifying threats to the wooded wetland ecosystems they use on their boreal breeding-grounds and their wintering-grounds in the southeastern United States. One hypothesis is that loss of wintering ground habitat, possibly in conjunction with competition or disease, is causing Rusty Blackbird decline. To determine contribution of wintering ground conditions, it is important to understand the behaviors …


Biomass Energy Production In Louisiana: A Gis Study On The Supply Chain, Anil Raj Kizhakkepurakkal Jan 2012

Biomass Energy Production In Louisiana: A Gis Study On The Supply Chain, Anil Raj Kizhakkepurakkal

LSU Doctoral Dissertations

One major drawback of biomass fuel is its bulky nature and the resulting high cost of transporting the fuel to the facility where the energy is being produced. Hence, supply chain of biomass residues plays a crucial role in determining the financial viability of bioenergy production. Transporting biomass for energy purposes more than 50 miles (80 km) is not considered economically feasible in most conditions. In the wood energy scenario, the maximum distance is more often restricted to distances of less than 200 km between production and consumption (via road). A study was done to determine logging residues and agricultural …


Composition And Physiological Characteristics Of The University Lake Ecosystem Phytoplankton Community: Impacts Of Seasonal And Episodic Events, Brianne Elizabeth Norris Jan 2012

Composition And Physiological Characteristics Of The University Lake Ecosystem Phytoplankton Community: Impacts Of Seasonal And Episodic Events, Brianne Elizabeth Norris

LSU Master's Theses

This research determined the changes in phytoplankton community composition in a shallow subtropical lake, influenced by urban surroundings. Specifically this research focused on the effects of seasonal progression and episodic events on the changing inorganic nutrient dynamics and the effects those dynamics had on the phytoplankton community composition and productivity. This research quantified gross primary production and respiration to determine if seasonality or episodic events were acting as forcing functions of the phytoplankton community composition. Water samples were collected weekly at three sites on the lake’s perimeter, as well as following episodic events, to monitor nitrate (NO3), phosphate (PO4-3), ammonium …


Semantically-Aware Data Discovery And Placement In Collaborative Computing Environments, Xinqi Wang Jan 2012

Semantically-Aware Data Discovery And Placement In Collaborative Computing Environments, Xinqi Wang

LSU Doctoral Dissertations

As the size of scientific datasets and the demand for interdisciplinary collaboration grow in modern science, it becomes imperative that better ways of discovering and placing datasets generated across multiple disciplines be developed to facilitate interdisciplinary scientific research.

For discovering relevant data out of large-scale interdisciplinary datasets. The development and integration of cross-domain metadata is critical as metadata serves as the key guideline for organizing data. To develop and integrate cross-domain metadata management systems in interdisciplinary collaborative computing environment, three key issues need to be addressed: the development of a cross-domain metadata schema; the implementation of a metadata management system …


An Extensible And Scalable Pilot-Mapreduce Framework For Data Intensive Applications On Distributed Cyberinfrastructure, Pradeep Kumar Mantha Jan 2012

An Extensible And Scalable Pilot-Mapreduce Framework For Data Intensive Applications On Distributed Cyberinfrastructure, Pradeep Kumar Mantha

LSU Master's Theses

The volume and complexity of data that must be analyzed in scientific applications is increasing exponentially. Often, this data is distributed; thus, the ability to analyze data by localizing it will yield limited returns. Therefore, an efficient processing of large distributed datasets is required, whilst ideally not introducing fundamentally new programming models or methods. For example, extending MapReduce - a proven effective programming model for processing large datasets, to work more effectively on distributed data and on different infrastructure (such as non-Hadoop, general-purpose clusters) is desirable. We posit that this can be achieved with an effective and efficient runtime environment …


The Effects Of Hydrologic Modifications On Floodplain Forest Tree Recruitment And Growth In The Mississippi River Alluvial Valley, Usa, Hugo Gee Jan 2012

The Effects Of Hydrologic Modifications On Floodplain Forest Tree Recruitment And Growth In The Mississippi River Alluvial Valley, Usa, Hugo Gee

LSU Doctoral Dissertations

Floodplains forests are productive and diverse ecosystems characterized by frequent riverine flooding. Levees and dams have eliminated or altered riverine flooding which can potentially affect floodplain tree recruitment and growth. Increased light availability from canopy disturbances may increase photosynthesis given sufficient soil moisture, but information on the combined effect of canopy disturbances and hydrologic modifications on tree recruitment and growth is lacking. I used dendrochronological techniques to reconstruct tree recruitment, growth (Quercus lyrata, Fraxinus pennsylvanica), and canopy disturbance patterns over a 90-year period at several floodplains in the Mississippi River Alluvial Valley, USA: an unleveed site below dams and two …


Recurrent Novae And Type Ia Supernova Progenitors, Ashley Sara Pagnotta Jan 2012

Recurrent Novae And Type Ia Supernova Progenitors, Ashley Sara Pagnotta

LSU Doctoral Dissertations

We investigated two types of stellar explosions, recurrent novae (RNe) and Type Ia supernovae (SNe Ia). SNe Ia are the most useful distance markers in astrophysics, but we do not know the identity of their progenitor systems. RNe are good progenitor candidates that consist of a white dwarf (WD) that accretes material from a companion star. The material builds on the surface of the WD until a runaway thermonuclear eruption is triggered, which ejects the accreted material and causes the system to brighten dramatically. We studied the demographics of the nova population and concluded that approximately 25% of classical novae …


Influences On Behavior Adaptations To Reduce Exposure To Environmental Hazards Among Residents Of Louisiana's Upper Industrial Corridor, Corrinthia Marie Hinton Jan 2012

Influences On Behavior Adaptations To Reduce Exposure To Environmental Hazards Among Residents Of Louisiana's Upper Industrial Corridor, Corrinthia Marie Hinton

LSU Master's Theses

Over the past century, the growth in petrochemical manufacturing within Louisiana’s Upper Industrial Corridor brought economic development, but also introduced toxic emissions and environmental exposure risks to residents of the area. For the citizens living in close proximity to multiple facilities there is the added risk of chemical exposure from environmentally hazardous accidents. This study seeks to gain insights into patterns of risk-reducing behaviors of residents in East Baton Rouge Parish so that better educational outreach programs can be developed. This research addresses the following questions: To what extent are residents of Baton Rouge taking steps to reduce environmental exposure …


Modeling The Spatial And Temporal Dynamics Of Coastal Marsh Birds, Bradley A. Pickens Jan 2012

Modeling The Spatial And Temporal Dynamics Of Coastal Marsh Birds, Bradley A. Pickens

LSU Doctoral Dissertations

Wetland birds are likely to be influenced by habitat at multiple spatial scales, yet few studies have investigated bird responses at both broad and fine scales. Northern Gulf Coast marshes are dynamic ecosystems, and they provide an ideal place to examine habitat across spatial and temporal scales. My research focused on the secretive marsh bird guild (i.e. bitterns, rails, gallinules, grebes) with an emphasis on the king rail (Rallus elegans), a species of high conservation concern. My objectives were to investigate the wetland bird-environment relationship across scales, and to model annual changes in bird distribution. Study sites were in the …