Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2004

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 9361 - 9390 of 9453

Full-Text Articles in Entire DC Network

Characteristics Of Hurricane Lili's Intensity Changes, Adele Marie Babin Jan 2004

Characteristics Of Hurricane Lili's Intensity Changes, Adele Marie Babin

LSU Master's Theses

Rapid intensity changes of Hurricane Lili in the Gulf of Mexico (GOM) were studied in three distinct ways: climatology, satellite remote sensing, and surface meteorological and oceanographic measurements. Each research methodology provided insight about Hurricane Lili's intensity behavior. A climatology of rapid and explosive intensifications of hurricanes was developed using minimum central pressure observations for the Atlantic tropical cyclone record. Results showed these events were frequent, especially in the GOM. The majority of intensification events occurred ≤ 24 h before landfall, with a third to one-half ≤ 12 h. Lili emerged anomalous as the only hurricane to weaken at a …


Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman Jan 2004

Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman

Dissertations and Theses

The Darlingtonia fens, found on serpentine soils in southern Oregon, are distinct communities that frequently undergo dramatic changes in size and shape in response to a wide array of environmental factors. Since few systems demonstrate a balance among high water tables, shallow soils, the presence of heavy metals, and limited nutrients, conservative efforts have been made to preserve them. This dissertation investigates the role of fire on nutrient cycling and succession in three separate fens, each a different time since fire. I specifically analyze the spatial distributions of soil properties, the physical and ecological characteristics of ecotones between Jeffrey pine …


Potential Contaminants At A Dredged Spoil Placement Site, Charles City County, Virginia, As Revealed By Sequential Extraction, Jianwu Tang, G. Richard Whittecar, Karen H. Johannesson, W. Lee Daniels Jan 2004

Potential Contaminants At A Dredged Spoil Placement Site, Charles City County, Virginia, As Revealed By Sequential Extraction, Jianwu Tang, G. Richard Whittecar, Karen H. Johannesson, W. Lee Daniels

OES Faculty Publications

Backfills of dredged sediments onto a former sand and gravel mine site in Charles City County, VA may have the potential to contaminate local groundwater. To evaluate the mobility of trace elements and to identify the potential contaminants from the dredged sediments, a sequential extraction scheme was used to partition trace elements associated with the sediments from the local aquifer and the dredged sediments into five fractions: exchangeable, acidic, reducible, oxidizable, and residual phases. Sequential extractions indicate that, for most of the trace elements examined, the residual phases account for the largest proportion of the total concentrations, and their total …


Interactive Regulation Of Dissolved Copper Toxicity By An Estuarine Microbial Community, Christina L. Dryden, Andrew S. Gordon, John R. Donat Jan 2004

Interactive Regulation Of Dissolved Copper Toxicity By An Estuarine Microbial Community, Christina L. Dryden, Andrew S. Gordon, John R. Donat

OES Faculty Publications

Cultured marine microorganisms under copper stress produce extracellular compounds having a high affinity for copper (copper-complexing ligands). These ligands are similar in binding strength to those found in natural waters, but few studies have examined the relationship between copper, copper-complexing ligand concentrations, and natural microbial populations. A series of in situ experiments in the Elizabeth River, Virginia, revealed that an intact estuarine microbial community responded to copper stress by production of extracellular, high-affinity copper-complexing ligands. The rate of ligand production was dependent on copper concentration and resulted in a reduction of the concentration of free cupric ions, Cu2+, …


Quasioptimality Of Some Spectral Mixed Methods, Jay Gopalakrishnan, Leszek Demkowicz Jan 2004

Quasioptimality Of Some Spectral Mixed Methods, Jay Gopalakrishnan, Leszek Demkowicz

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we construct a sequence of projectors into certain polynomial spaces satisfying a commuting diagram property with norm bounds independent of the polynomial degree. Using the projectors, we obtain quasioptimality of some spectralmixed methods, including the Raviart–Thomas method and mixed formulations of Maxwell equations. We also prove some discrete Friedrichs type inequalities involving curl.


Section 2254(D) Of The Federal Habeas Statute: Is It Beyond Reason?, Evan Tsen Lee Jan 2004

Section 2254(D) Of The Federal Habeas Statute: Is It Beyond Reason?, Evan Tsen Lee

Faculty Scholarship

No abstract provided.


Asymptotic Laplace Transforms, Claudiu Mihai Jan 2004

Asymptotic Laplace Transforms, Claudiu Mihai

LSU Doctoral Dissertations

In this work we discuss certain aspects of the classical Laplace theory that are relevant for an entirely analytic approach to justify Heaviside's operational calculus methods. The approach explored here suggests an interpretation of the Heaviside operator ${cdot}$ based on the "Asymptotic Laplace Transform." The asymptotic approach presented here is based on recent work by G. Lumer and F. Neubrander on the subject. In particular, we investigate the two competing definitions of the asymptotic Laplace transform used in their works, and add a third one which we suggest is more natural and convenient than the earlier ones given. We compute …


Synthesis, Separation And Reactivities Of Multidentate Phosphine Ligands And Investigation Into Dirhodium Hydroformylation And Hydrocarboxylation Catalysis, David Aubry Jan 2004

Synthesis, Separation And Reactivities Of Multidentate Phosphine Ligands And Investigation Into Dirhodium Hydroformylation And Hydrocarboxylation Catalysis, David Aubry

LSU Doctoral Dissertations

A dirhodium homogeneous hydroformylation catalyst based on a tetraphosphine ligand, rac-Et2PCH2CH2P(Ph)CH2P(Ph)CH2CH2PEt2, rac-et,ph-P4, is under investigation. The ligand synthesis produces a racemic mixture and a facile and efficient method of separation of the racemic and meso diastereomers was achieved through reaction of et,ph-P4 with two equivalents of NiCl2 in EtOH to yield an almost quantitatively isolable precipitate of meso-Ni2Cl4(et,ph-P4) and the soluble rac-Ni2Cl4(et,ph-P4). Subsequent cyanolysis of these complexes liberates the et,ph-P4 ligand, and the …


Watermarking Using Decimal Sequences, Navneet Kumar Mandhani Jan 2004

Watermarking Using Decimal Sequences, Navneet Kumar Mandhani

LSU Master's Theses

This thesis introduces the use of decimal sequences in watermarking to hide information for authentication. The underlying system is based on code division multiple access (CDMA), which is a form of spread spectrum communication. Different algorithms for the use of decimal sequences have been formulated for use in black and white images. The watermark is spread across the carrier image by using the d- sequences of optimal period and retrieval is made by the use of correlation. Matlab version 6.5 was used to implement the algorithms discussed in this thesis. The advantage of using d-sequences over PN sequences is that …


The Fidelity Of Red Snapper (Lutjanus Campechanus) To Petroleum Platforms And Artificial Reefs In The Northern Gulf Of Mexico, Megan Blythe Peabody Jan 2004

The Fidelity Of Red Snapper (Lutjanus Campechanus) To Petroleum Platforms And Artificial Reefs In The Northern Gulf Of Mexico, Megan Blythe Peabody

LSU Master's Theses

The habitat value of petroleum platforms for red snapper, Lutjanus campechanus, is poorly understood. However, it is widely recognized by both scientists and fishermen that the presence of platforms in the northern Gulf of Mexico (GOM) has affected the distribution of red snapper by the addition of hard substrate habitat. I evaluated the habitat value of standing and toppled platforms by monitoring the fidelity of red snapper to these structures with acoustic telemetry. In May 2003, 125 red snapper were captured with hook and line at several platforms in a 35-km2 portion of the South Timbalier oil and gas lease …


The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen Jan 2004

The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen

LSU Master's Theses

Wetlands improve water quality through sedimentation and the uptake of excess nutrients. As human population increases in the coastal zone, wetlands receive greater nutrient inputs. These additional nutrients may accelerate microbial activity, leading to faster decomposition rates. This decomposition could exceed belowground organic matter production, resulting in a net reduction in soil organic matter accumulation and vertical marsh accretion. The effects of nutrient enrichment on belowground organic matter decomposition in subtropical marshes have received little attention. As such, this research examined the effects of four levels of nitrogen combined with two levels of phosphorus enrichment on belowground decomposition through the …


Accelerating The Transition To A Sustainable Society, Christopher Brian Bennett Jan 2004

Accelerating The Transition To A Sustainable Society, Christopher Brian Bennett

LSU Master's Theses

As human populations increase, available land and resources decrease, and we begin to better understand the impacts of human activity on the environment, a strategy for human development that meets both the needs of society and the environment is being increasingly called upon. This movement has come to be known as sustainability. While this term is prevalent in the design and planning communities, it is important that this concept be brought to the attention of the general public, whom will ultimately decide the success or failure of this scheme. The question then is how to begin implementation of sustainable practices, …


Parallel Molecular Dynamics Simulations Of Antimicrobial Peptides, Svetlana V. Oard Jan 2004

Parallel Molecular Dynamics Simulations Of Antimicrobial Peptides, Svetlana V. Oard

LSU Master's Theses

Molecular dynamics (MD) simulations of the wheat antimicrobial peptide â-purothionin were carried out in explicit water (~14,000 atoms) using an all-atom model. The structural properties of the peptide as a function of MD simulation, temperature, and presence of the mono- and divalent metal ions were investigated. The accuracy and scalability tests of the code Peach 3.8 for our system were performed on the Intel Xeon-based Linux cluster SuperHelix at Louisiana State University (LSU). The code showed the reliable accuracy and the parallel efficiency of 0.61 for ~14,000 particles on 16 processors. The microcanonical (MC) MD simulation of â-purothionin in water …


State-Level Environmental Risk Perception: An Analysis Of 20 Comparative Risk Reports, Mandy Green Jan 2004

State-Level Environmental Risk Perception: An Analysis Of 20 Comparative Risk Reports, Mandy Green

LSU Master's Theses

Research was conducted to identify the states that compiled Comparative Risk Reports and the year in which the study was completed. The information relating to the type of committee that compiled the risk report and the final risk rankings was examined. State Comparative Risk Reports were collected for twenty states and the risk rankings that each state compiled were reviewed to determine which states ranked third generation environmental problems and the ranking that those problems were given. The risk reports compiled by each state were also used to determine which states ranked natural resource based problems and the ranking that …


Mortality Of Pen-Raised White-Tailed Deer (Odocoileus Virginianus) Released On Three Areas In Louisiana, Barret Keith Fortier Jan 2004

Mortality Of Pen-Raised White-Tailed Deer (Odocoileus Virginianus) Released On Three Areas In Louisiana, Barret Keith Fortier

LSU Master's Theses

I monitored 60 radio-collared and tagged pen-raised white-tailed deer (Odocoileus virginianus) to ascertain mortality rates on three areas in Louisiana from April 2001 - April 2002. Two of 60 were not used in the analysis because mortality occurred from complications with darting and an affixed radio-collar. Study deer were exposed to legal hunting mortality only if they emigrated from the three study areas. Twenty deer were released to the wild on the Louisiana State University Deer Study Area (LSUDSA) (4,810 ha), where 9 of 20 (45%) suffered mortality. Harvest accounted for 56%, vehicles 22%, and other 22% of the mortality …


Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith Jan 2004

Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith

LSU Master's Theses

Little is known about the morphometrics and the feeding ecology of paddlefish in Louisiana. I examined the morphometrics and feeding ecology of paddlefish from the Mermentau River, Louisiana from March 2002 to February 2003. Paddlefish were examined morphometrically by taking measurements of eye-fork length (EFL), body cavity length (BCL), girth (G), vent girth (VG), mouth vertical (MTB), mouth horizontal (MSS), and mouth gullet bottom (MGB) to determine which parameters would give a better estimate of weight (W). Regression analysis resulted in a morphometric model of the form: logW = 10.10 + 1.52 (logEFL) + 1.21 (logG) + 0.24 (logVG) (r2 …


Our Selma Is Here: The Political And Legal Struggle For Educational Equality In Denver, Colorado, And Multiracial Conundrums In American Jurisprudence, Tom I. Romero Ii Jan 2004

Our Selma Is Here: The Political And Legal Struggle For Educational Equality In Denver, Colorado, And Multiracial Conundrums In American Jurisprudence, Tom I. Romero Ii

Scholarly Works

No abstract provided.


Environmental Swap Energy And Role Of Configurational Entropy In Transfer Of Small Molecules From Water Into Alkanes, Pavel Smejtek, Robert Campbell Word Jan 2004

Environmental Swap Energy And Role Of Configurational Entropy In Transfer Of Small Molecules From Water Into Alkanes, Pavel Smejtek, Robert Campbell Word

Physics Faculty Publications and Presentations

We studied the effect of segmented solvent molecules on the free energy of transfer of small molecules from water into alkanes (hexane, heptane, octane, decane, dodecane, tetradecane, and hexadecane). For these alkanes we measured partition coefficients of benzene, 3-methylindole (3MI), 2,3,4,6-tetrachlorophenol (TeCP), and 2,4,6-tribromophenol (TriBP) at 3, 11, 20, 3, and 47 °C. For 3MI, TeCP, and TriBP the dependence of free energy of transfer on length of alkane chains was found to be very different from that for benzene. In contrast to benzene, the energy of transfer for 3MI, TeCP, and TriBP was independent of the number of carbons …


Prospect Theory And The Cyprus Conflict: Analyzing Decisionmaking In The Turkish Cypriot President, Tarah Marie Wheeler Jan 2004

Prospect Theory And The Cyprus Conflict: Analyzing Decisionmaking In The Turkish Cypriot President, Tarah Marie Wheeler

Political Science Masters Theses

Rauf R. Denktash, the Turkish Cypriot president and leader of the Turkish Republic of Northern Cyprus, has made many decisions not to negotiate with his Greek Cypriot counterpart for peace and reunification on the island of Cyprus. Traditional rational choice theories do not explain his willingness to sacrifice political power for his policy goals in risky choices. Prospect theory, a cognitive behavioral theory of decisionmaking, may help to explain why Denktash makes those risky choices by showing that decisionmakers who feel themselves to be in the domain of losses will make risky choices to gain their reference point, the location …


Directed Extended Dependency Analysis For Data Mining, Thaddeus T. Shannon, Martin Zwick Jan 2004

Directed Extended Dependency Analysis For Data Mining, Thaddeus T. Shannon, Martin Zwick

Complex Systems Faculty Publications and Presentations

Extended dependency analysis (EDA) is a heuristic search technique for finding significant relationships between nominal variables in large data sets. The directed version of EDA searches for maximally predictive sets of independent variables with respect to a target dependent variable. The original implementation of EDA was an extension of reconstructability analysis. Our new implementation adds a variety of statistical significance tests at each decision point that allow the user to tailor the algorithm to a particular objective. It also utilizes data structures appropriate for the sparse data sets customary in contemporary data mining problems. Two examples that illustrate different approaches …


A Comparison Of Modified Reconstructability Analysis And Ashenhurst‐Curtis Decomposition Of Boolean Functions, Anas Al-Rabadi, Marek Perkowski, Martin Zwick Jan 2004

A Comparison Of Modified Reconstructability Analysis And Ashenhurst‐Curtis Decomposition Of Boolean Functions, Anas Al-Rabadi, Marek Perkowski, Martin Zwick

Complex Systems Faculty Publications and Presentations

Modified reconstructability analysis (MRA), a novel decomposition technique within the framework of set‐theoretic (crisp possibilistic) reconstructability analysis, is applied to three‐variable NPN‐classified Boolean functions. MRA is superior to conventional reconstructability analysis, i.e. it decomposes more NPN functions. MRA is compared to Ashenhurst‐Curtis (AC) decomposition using two different complexity measures: log‐functionality, a measure suitable for machine learning, and the count of the total number of two‐input gates, a measure suitable for circuit design. MRA is superior to AC using the first of these measures, and is comparable to, but different from AC, using the second.


Reversible Modified Reconstructability Analysis Of Boolean Circuits And Its Quantum Computation, Anas Al-Rabadi, Martin Zwick Jan 2004

Reversible Modified Reconstructability Analysis Of Boolean Circuits And Its Quantum Computation, Anas Al-Rabadi, Martin Zwick

Complex Systems Faculty Publications and Presentations

Modified Reconstructability Analysis (MRA) can be realized reversibly by utilizing Boolean reversible (3,3) logic gates that are universal in two arguments. The quantum computation of the reversible MRA circuits is also introduced. The reversible MRA transformations are given a quantum form by using the normal matrix representation of such gates. The MRA-based quantum decomposition may play an important role in the synthesis of logic structures using future technologies that consume less power and occupy less space.


Modified Reconstructability Analysis For Many-Valued Functions And Relations, Anas Al-Rabadi, Martin Zwick Jan 2004

Modified Reconstructability Analysis For Many-Valued Functions And Relations, Anas Al-Rabadi, Martin Zwick

Complex Systems Faculty Publications and Presentations

A novel many-valued decomposition within the framework of lossless Reconstructability Analysis is presented. In previous work, Modified Recontructability Analysis (MRA) was applied to Boolean functions, where it was shown that most Boolean functions not decomposable using conventional Reconstructability Analysis (CRA) are decomposable using MRA. Also, it was previously shown that whenever decomposition exists in both MRA and CRA, MRA yields simpler or equal complexity decompositions. In this paper, MRA is extended to many-valued logic functions, and logic structures that correspond to such decomposition are developed. It is shown that many-valued MRA can decompose many-valued functions when CRA fails to do …


State-Based Reconstructability Analysis, Martin Zwick, Michael S. Johnson Jan 2004

State-Based Reconstructability Analysis, Martin Zwick, Michael S. Johnson

Complex Systems Faculty Publications and Presentations

Reconstructability analysis (RA) is a method for detecting and analyzing the structure of multivariate categorical data. While Jones and his colleagues extended the original variable‐based formulation of RA to encompass models defined in terms of system states, their focus was the analysis and approximation of real‐valued functions. In this paper, we separate two ideas that Jones had merged together: the “g to k” transformation and state‐based modeling. We relate the idea of state‐based modeling to established variable‐based RA concepts and methods, including structure lattices, search strategies, metrics of model quality, and the statistical evaluation of model fit for analyses based …


Reconstructability Analysis Detection Of Optimal Gene Order In Genetic Algorithms, Martin Zwick, Stephen Shervais Jan 2004

Reconstructability Analysis Detection Of Optimal Gene Order In Genetic Algorithms, Martin Zwick, Stephen Shervais

Complex Systems Faculty Publications and Presentations

The building block hypothesis implies that genetic algorithm efficiency will be improved if sets of genes that improve fitness through epistatic interaction are near to one another on the chromosome. We demonstrate this effect with a simple problem, and show that information-theoretic reconstructability analysis can be used to decide on optimal gene ordering.


A Comparison Of System Dynamics And Agent-Based Simulationapplied To The Study Of Cellular Receptor Dynamics, Wayne W. Wakeland, Edward J. Gallaher, Louis Macovsky, C. Athena Aktipis Jan 2004

A Comparison Of System Dynamics And Agent-Based Simulationapplied To The Study Of Cellular Receptor Dynamics, Wayne W. Wakeland, Edward J. Gallaher, Louis Macovsky, C. Athena Aktipis

Complex Systems Faculty Publications and Presentations

Cellular receptor dynamics are often analyzed using differential equations, making system dynamics (SD) a candidate methodology. In some cases it may be useful to model the phenomena at the biomolecular level, especially when concentrations and reaction probabilities are low and might lead to unexpected behavior modes. In such cases, agent-based simulation (ABS) may be useful. We show the application of both SD and ABS to simulate non-equilibrium ligand-receptor dynamics over a broad range of concentrations, where the probability of interaction varies from low to very low. Both approaches offer much to the researcher and are complementary. We did not find …


Using Design Of Experiments, Sensitivity Analysis, And Hybrid Simulation To Evaluate Changes To A Software Development Process: A Case Study, Wayne Wakeland, Robert H. Martin, David Raffo Jan 2004

Using Design Of Experiments, Sensitivity Analysis, And Hybrid Simulation To Evaluate Changes To A Software Development Process: A Case Study, Wayne Wakeland, Robert H. Martin, David Raffo

Complex Systems Faculty Publications and Presentations

Hybrid simulation models combine the high-level project issues of System Dynamics models along with the detailed process representation of discrete event simulation models. Hybrid models not only capture the best of both of these simulation paradigms, but they also are able to address new issues that are important in managing complex real-world development projects that neither the System Dynamics nor Discrete Event simulation paradigms are able to address alone.

In order to reap the full benefits from a simulation model, a structured approach for analyzing model results is necessary. The recommended approach is a combination of the Design of Experiments …


Narrative Understanding And Understanding Narrative, Sarah E. Worth Jan 2004

Narrative Understanding And Understanding Narrative, Sarah E. Worth

Contemporary Aesthetics (Journal Archive)

In this paper I deal with the question of how it is that we have emotional responses to things that we do not believe in the reality of, specifically things like characters and events in literature and film (the paradox of fiction). The direction in which I wish to take this query is not the traditional philosophical approach to this question, however. There has been much written on this particular approach, and because of this I think that it is becoming, in philosophical effect, stuck. What I wish to do in what follows is to approach this question from a …


Ethical Autonomism: The Work Of Art As A Moral Agent, Rob Van Gerwen Jan 2004

Ethical Autonomism: The Work Of Art As A Moral Agent, Rob Van Gerwen

Contemporary Aesthetics (Journal Archive)

Much contemporary art seems morally out of control. Yet, philosophers seem to have trouble finding the right way to morally evaluate works of art. The debate between autonomists and moralists, I argue, has turned into a stalemate due to two mistaken assumptions. Against these assumptions, I argue that the moral nature of a work's contents does not transfer to the work and that, if we are to morally evaluate works we should try to conceive of them as moral agents. Ethical autonomism holds that art's autonomy consists in its demand that art appreciators take up an artistic attitude. A work's …


Talk To The Animals: A Short Comment On Wolfgang Welsch's "Animal Aesthetics", Stefán Snaevarr Jan 2004

Talk To The Animals: A Short Comment On Wolfgang Welsch's "Animal Aesthetics", Stefán Snaevarr

Contemporary Aesthetics (Journal Archive)

I voice some concern about Wolfgang Welsch's defense of the theory that animals can feel aesthetic pleasure. My first concern is epistemological: it is hard to see how we can find out whether they actually feel such pleasures. My second concern is conceptual: aesthetic pleasures have intentional objects and are woven into fallible judgments. It is hard to see that animals have such objects and can perform such judgments.