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Quantum Convolution Of Linearly Recursive Sequences, Siu Hung Ng, Earl J. Taft Dec 1997

Quantum Convolution Of Linearly Recursive Sequences, Siu Hung Ng, Earl J. Taft

Faculty Publications

No abstract provided.

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Chern-Simons States In Spin-Network Quantum Gravity, Rodolfo Gambini, Jorge Griego, Jorge Pullin Nov 1997

Chern-Simons States In Spin-Network Quantum Gravity, Rodolfo Gambini, Jorge Griego, Jorge Pullin

Faculty Publications

In the context of canonical quantum gravity in terms of Ashtekar's new variables, it is known that there exists a state that is annihilated by all the quantum constraints and that is given by the exponential of the Chern-Simons form constructed with the Asthekar connection. We make a first exploration of the transform of this state into the spin-network representation of quantum gravity. The discussion is limited to trivalent nets with planar intersections. We adapt an invariant of tangles to construct the transform and study the action of the Hamiltonian constraint on it. We show that the first two coefficients …

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Unavoidable Minors Of Large 3-Connected Matroids, Guoli Ding, Bogdan Oporowski, James Oxley, Dirk Vertigan Nov 1997

Unavoidable Minors Of Large 3-Connected Matroids, Guoli Ding, Bogdan Oporowski, James Oxley, Dirk Vertigan

Faculty Publications

This paper proves that, for every integernexceeding two, there is a numberN(n) such that every 3-connected matroid with at leastN(n) elements has a minor that is isomorphic to one of the following matroids: an (n+2)-point line or its dual, the cycle or cocycle matroid ofK3,n, the cycle matroid of a wheel withnspokes, a whirl of rankn, or ann-spike. A matroid is of the last type if it has ranknand consists ofnthree-point lines through a common point such that, for allkin {1,2,...,n-1}, the union of every set ofkof these lines has rankk+1. © 1997 Academic Press.

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Bioremediation Of Creosote Contaminated Soils In An Old Wood Preserving Facility, Claudia Rush May 1997

Bioremediation Of Creosote Contaminated Soils In An Old Wood Preserving Facility, Claudia Rush

Honors Capstones

No abstract provided.

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Synthesis Of 1-Alloc-Piperidine-4-Fmoc-Amino-4-Carboxylic Acid: A Novel, Protected ?,?- Disubstituted Amino Acid, Muna K. Thalji Apr 1997

Synthesis Of 1-Alloc-Piperidine-4-Fmoc-Amino-4-Carboxylic Acid: A Novel, Protected ?,?- Disubstituted Amino Acid, Muna K. Thalji

Honors Capstones

No abstract provided.

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Louisiana Agriculture Magazine, Spring 1997, Lsu Agricultural Experiment Station Apr 1997

Louisiana Agriculture Magazine, Spring 1997, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Matroids Arisen From Matrogenic Graphs, Guoli Ding, Peter L. Hammer Mar 1997

Matroids Arisen From Matrogenic Graphs, Guoli Ding, Peter L. Hammer

Faculty Publications

Let G be a finite simple graph and let ℐ(G) be the set of subsets X of V(G) such that the subgraph of G induced by X is threshold. If ℐ(G) is the independence system of a matroid, then G is called matrogenic [3]. In this paper, we characterize matroids arising from matrogenic graphs.

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Wetland Loss In The Northern Gulf Of Mexico: Multiple Working Hypotheses, R. Eugene Turner Mar 1997

Wetland Loss In The Northern Gulf Of Mexico: Multiple Working Hypotheses, R. Eugene Turner

Faculty Publications

I examined four hypotheses about causes for the dramatically high coastal wetland losses (0.86% yr−1) in the northern Gulf of Mexico: an extensive dredged canal and spoil bank network, a decline in sediments in the Mississippi River during the 1950s, Mississippi River navigation and flood protection levees, and salinity changes. Natural factors contributing to these habitat changes include eustatic sea-level rise and geological compaction, which appear to have remained relatively constant this century, although variation does occur. These four hypotheses were tested using data on land-to-water changes in 15-min quadrangle maps inventoried for four intervals between the 1930s and 1990. …

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A Micro-Mechanical Fatigue Damage Model For Uni-Directional Metal Matrix Composites., Rainer Echle Jan 1997

A Micro-Mechanical Fatigue Damage Model For Uni-Directional Metal Matrix Composites., Rainer Echle

LSU Historical Dissertations and Theses

A micro-mechanical damage model for high cycle fatigue loading based on thermo-dynamical principles is developed for uni-directional continuous fiber reinforced metal matrix composites. The model uses a micro-mechanical based theory to predict the fatigue damage evolution in the individual constituents of the composite material, namely the fibers and the matrix, from which the overall fatigue damage evolution in the composite is obtained. The micro-mechanical analysis is performed for each individual constituent using stress and strain concentration tensors based on the Mori-Tanaka method. A fatigue damage criterion based on thermo-dynamical principles is developed and applied to each of the constituents. Fatigue …

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Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly Jan 1997

Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly

LSU Historical Dissertations and Theses

An advanced prototype computer-assisted deep water drilling well control system was developed using process control technology. The goal of the system was to improve rig safety by reducing the potential for surface and underground blowouts through providing enhanced bottom hole and casing seat pressure control during the well kill process. The system developed is capable of full computer control of the fluid pump and drilling choke control functions during normal well control operations. The system provides computer-assistance in collecting and curve fitting slow circulation rate pump pressure data, in developing a well kill program (kill sheet), and in detecting anomalies …

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A Vector-Valued Operational Calculus And Abstract Cauchy Problems., Boris Baeumer Jan 1997

A Vector-Valued Operational Calculus And Abstract Cauchy Problems., Boris Baeumer

LSU Historical Dissertations and Theses

Initial and boundary value problems for linear differential and integro-differential equations are at the heart of mathematical analysis. About 100 years ago, Oliver Heaviside promoted a set of formal, algebraic rules which allow a complete analysis of a large class of such problems. Although Heaviside's operational calculus was entirely heuristic in nature, it almost always led to correct results. This encouraged many mathematicians to search for a solid mathematical foundation for Heaviside's method, resulting in two competing mathematical theories: (a) Laplace transform theory for functions, distributions and other generalized functions, (b) J. Mikusinski's field of convolution quotients of continuous functions. …

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Unavoidable Minors Of Graphs Of Large Type., John Joseph Dittmann Jr Jan 1997

Unavoidable Minors Of Graphs Of Large Type., John Joseph Dittmann Jr

LSU Historical Dissertations and Theses

In this paper, we study one measure of complexity of a graph, namely its type. The type of a graph G is defined to be the minimum number n such that there is a sequence of graphs $G = G\sb0, G\sb1,\... , G\sb{n},$ where $G\sb{i}$ is obtained by contracting or deleting one edge from each block of $G\sb{i-1}$, and where $G\sb{n}$ is edgeless. We show that a 3-connected graph has large type if and only if it has a minor isomorphic to a large fan. Furthermore, we show that if a graph has large type, then it has a minor …

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Evaluation Of Water-Seeded No-Till Rice Culture With Respect To Weeds And Seedling Disease., Roland Detleo Mendt Jan 1997

Evaluation Of Water-Seeded No-Till Rice Culture With Respect To Weeds And Seedling Disease., Roland Detleo Mendt

LSU Historical Dissertations and Theses

Field studies were conducted over three years to evaluate preplant postemergence herbicides for red rice control in rice under no-till water-seeded culture. Application of paraquat or sulfosate plus thiobencarb and paraquat alone 3 days before seeding (DBS) resulted in the greatest red rice control 11 weeks after seeding (WAS). Rice yield was increased and percent red rice in rice grain decreased when paraquat or sulfosate was applied in combination with thiobencarb compared with the nontreated control. Rice yield was increased when herbicides were applied 3 and 7 DBS as compared with 14 and 28 DBS. Aqueous extracts of cursed buttercup, …

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Southern Families And Their Daughters: The Self And The System In Selected Texts By Grau, Gilchrist, Welty, Spencer, And Douglas., Jo K. Galle Jan 1997

Southern Families And Their Daughters: The Self And The System In Selected Texts By Grau, Gilchrist, Welty, Spencer, And Douglas., Jo K. Galle

LSU Historical Dissertations and Theses

In this interdisciplinary study, I apply the materials of family systems theory to the study of five twentieth-century literary texts, each written by a Southern white woman. Arranged in the order they will appear in this study, the five texts are The Keepers of the House (1964) by Shirley Ann Grau; Net of Jewels (1992) by Ellen Gilchrist; The Golden Apples (1949) by Eudora Welty; The Voice at the Back Door (1956) by Elizabeth Spencer; and Can't Quit You, Baby (1988) by Ellen Douglas. In the analysis of these books--all examples of domestic and social realism--I analyze and measure the …

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Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero Jan 1997

Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero

LSU Historical Dissertations and Theses

A new interpretation method that allows for the determination of the fluid type present in a formation of interest was developed. The new method is referred to as the "Three Neutron Porosity Log". The method is based on an algorithm that determines three apparent neutron porosities. These porosities, derived from the raw counts of the dual-spaced neutron tool, have three different radii of investigation. All three neutron porosities, near, far, and ratio, when properly calibrated read the true porosity in water-bearing zones. In oil or gas-bearing zones the mud filtrate invasion profile will cause the three apparent neutron porosities to …

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The Myth Of Narcissus And The Narcissistic Structure., Joachim Conrad Hermann Vogeler Jan 1997

The Myth Of Narcissus And The Narcissistic Structure., Joachim Conrad Hermann Vogeler

LSU Historical Dissertations and Theses

Since Freud's article "On Narcissism," behavioral psychologists have predominantly viewed this phenomenon as a personality disorder. This dissertation, in contrast, provides a psychoanalytic, i.e., Lacanian reading of the myth of Narcissus as it is recorded in classical literature, and brings about an understanding of the myth's underlying structure. The four fundamental exigencies of the myth's structure include the incest prohibition which symbolically castrates the human subject, the incestuous desire as a result of this prohibition, the displacement of this desire for another imaginary object, and the obsessive quest of that image as the symptom. This structure--defined as narcissistic structure and …

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A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs Jan 1997

A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs

LSU Historical Dissertations and Theses

In an investigation of allelopathy in the Florida scrub, bioassays with terpenes were performed against: Lactuca sativa, Rudbeckia hirta, Leptochloa dubia and Schizachyrium scoparium. Cineole was phytotoxic against Rudbeckia at 17 ppm and Lactuca at 165 ppm. (S)-camphor was phytotoxic to Rudbeckia at 1 ppm, Lactuca at 28 ppm, and Leptochloa and Schizachyrium at 134 ppm. (R)-Camphor, myrtenol and myrtenal were phytotoxic against Rudbeckia at concentrations of 28, 25 and 15 ppm respectively. Farnesol stimulated the germination of Schizachyrium at concentrations up to 50 ppm and at 100 ppm it reduced the radicle length of all test species. Geraniol stimulated …

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Efficient Mapping Of Neural Network Models On A Class Of Parallel Architectures., Behnam Seyed Arad Jan 1997

Efficient Mapping Of Neural Network Models On A Class Of Parallel Architectures., Behnam Seyed Arad

LSU Historical Dissertations and Theses

This dissertation develops a formal and systematic methodology for efficient mapping of several contemporary artificial neural network (ANN) models on k-ary n-cube parallel architectures (KNC's). We apply the general mapping to several important ANN models including feedforward ANN's trained with backpropagation algorithm, radial basis function networks, cascade correlation learning, and adaptive resonance theory networks. Our approach utilizes a parallel task graph representing concurrent operations of the ANN model during training. The mapping of the ANN is performed in two steps. First, the parallel task graph of the ANN is mapped to a virtual KNC of compatible dimensionality. This involves decomposing …

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Electron Scattering Studies In The Framework Of The Symplectic Shell Model., Jutta Escher Jan 1997

Electron Scattering Studies In The Framework Of The Symplectic Shell Model., Jutta Escher

LSU Historical Dissertations and Theses

Electron scattering offers numerous advantages for studying nuclear structure: the weakness of the electromagnetic interaction, the precise knowledge of the reaction mechanism, the ability to vary independently the transferred momentum and energy, as well as the excellent spatial resolution that can be obtained with the point-like probing particles, have made this approach a valuable tool in nuclear physics. Scattering experiments provide crucial tests for the applicability and limitations of modern nuclear models and further our understanding of the nucleon-nucleon interaction and its modifications in nuclear matter. A microscopic theory for deformed nuclei, which takes proper account of the Exclusion Principle …

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The Organ Symphony: Its Evolution In France And Transformation In Selected Works By American Composers Of The Twentieth Century., Richard Edward Beckford Jan 1997

The Organ Symphony: Its Evolution In France And Transformation In Selected Works By American Composers Of The Twentieth Century., Richard Edward Beckford

LSU Historical Dissertations and Theses

During the mid to late nineteenth century organ building and organ music in France underwent radical change. The French organ of the early nineteenth century was still the instrument of the French Classical school, the instrument of Clicquot and his predecessors. These instruments were limited in manual and pedal compass, variety and power of stops, and in their ability to vary expression and nuance. The great organ builder Aristide Cavaille-Coll changed all this and introduced to France instruments that were capable of tremendous tonal variety, nuance, and expressions. His instruments introduced many tonal changes particularly harmonic stops and stops that …

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New Developments In Portable Fast Gas Chromatography., Elena Ursula Ehrmann Jan 1997

New Developments In Portable Fast Gas Chromatography., Elena Ursula Ehrmann

LSU Historical Dissertations and Theses

Currently commercially available portable gas chromatographs are suitable only for the analysis of volatile organic compounds, and do not include temperature programming capability. This dissertation presents the development of a novel direct at-column heater design and a pressure driven injection system that is compatible with semi-volatile analytes. The collinear and coaxial at-column heater designs incorporate heater and temperature sensing elements placed along the column. Resistive heating controls the column temperature via a feedback circuit and a software selected program. Linear temperature programming ramps up to 14$\sp\circ$C/s were obtained, with a total power consumption of less than 100 Watt. The accuracy …

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An Analysis Of Medium Of Exchange In Takeovers., Yuan-Shing Liao Jan 1997

An Analysis Of Medium Of Exchange In Takeovers., Yuan-Shing Liao

LSU Historical Dissertations and Theses

This dissertation provides a detailed analysis of the medium of exchange in corporate takeovers. Previous theoretical works and empirical evidence suggest three distinct (but not necessarily mutually exclusive) elements of information asymmetry: the bidder's value, the target's value, and the synergy from a takeover. Chapter two of this dissertation integrates the theory of financial intermediation into the research of the medium of exchange in takeovers. The research question is how the bidders with favorable information employ financial intermediaries, such as accounting firms, investment banks, and commercial banks, to reduce the market's unfavorable reaction to announcements of equity-financed takeovers. Chapter three …

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Diverse Roads To Literacy: Examining The Literacy Learning Of Six First Graders., Deborah Rickards Jan 1997

Diverse Roads To Literacy: Examining The Literacy Learning Of Six First Graders., Deborah Rickards

LSU Historical Dissertations and Theses

The purpose of this descriptive multiple-case qualitative study was to observe six students--three students who initially experienced difficulty with early literacy tasks and three who initially encountered success. It was conducted in a classroom with an exemplary teacher using literature-based instruction, the writing process, integration across curricular areas, and an intervention strategy designed to accelerate the learning of the students who encountered difficulties with literacy tasks. This research was conducted to examine the following questions: (a) How did each child interact with reading/writing materials and with other readers and writers within the classroom? (b) how did the teacher interact with …

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An Identification Of Primary Evaluands As Perceived By Undergraduate Students And Faculty In A College Of Agriculture., Karen Renee Juneau Jan 1997

An Identification Of Primary Evaluands As Perceived By Undergraduate Students And Faculty In A College Of Agriculture., Karen Renee Juneau

LSU Historical Dissertations and Theses

This study determined appropriate evaluands for a College of Agriculture based on the perceptions of two shareholder groups of the college, the faculty and undergraduate students. Student opinions about their college experiences appeared related to the goals and influences that prompted them to attend college. These goals and influences determined what they expected from their college experience. There were three parts to the study; a pilot study, an undergraduate student study and a faculty study. Undergraduate students were classified based on two break points, gender and nontraditional/traditional student status. There were four focus groups conducted for the study and fourteen …

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Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer Jan 1997

Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer

LSU Historical Dissertations and Theses

The mechanism of fish protein solubilization by acid hydrolysis at elevated temperatures was investigated. Rate expressions for the solubilization were determined using pilot scale data with two different rate determination methods. A postulated mechanism was verified and estimated rates were evaluated on five independent verification experiments. A functional relationship between nonprotein byproduct concentration and whiteness of fish protein hydrolysate (FPH) was developed. Initial and set-point operating variables were calculated to produce FPH with acceptable color characteristics for food use. A batch reactor was used for duplicate hydrolysis trials conducted at three acid and three temperature levels for four hours. Samples …

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Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos Jan 1997

Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos

LSU Historical Dissertations and Theses

We apply stochastic techniques towards the solution of the two-dimensional Laplace's equation in boundary value problems encountered in the calculation of electrostatic potentials in electron lenses and deflectors. The justification of these techniques arises from an astonishingly simple but far-reaching principle, which has been known for a long time but has been rarely used: the potential at any point in the interior of a charge-free region can be calculated by performing random walks starting at this point and terminating at the boundary of the region--the potential is then the average of the potential boundary values (assumed known) over the random …

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Teacher Conceptions And The Curriculum: A Longitudinal, Multicase Study Of College Chemistry Teaching., Charles J. Killebrew Jan 1997

Teacher Conceptions And The Curriculum: A Longitudinal, Multicase Study Of College Chemistry Teaching., Charles J. Killebrew

LSU Historical Dissertations and Theses

Strategic innovations and interventions to reform college science teaching will be required to promote the retention and achievement of those students who might otherwise elect to defect at the entry-level courses. The extent to which this can be achieved will depend upon educational research into ways that the science curriculum can be restructured to accomplish the dual function of enhancing science literacy while promoting recruitment to scientific careers. To explore these issues, four introductory college chemistry classes were observed over a period of two years. The classes were designated either as traditional or conceptual. Selection into these categories was based …

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A Geometric Method For Location Of Gravitational Wave Sources, Nadja S. Magalhães, Warren W. Johnson, Carlos Frajuca, Odylio D. Aguiar Jan 1997

A Geometric Method For Location Of Gravitational Wave Sources, Nadja S. Magalhães, Warren W. Johnson, Carlos Frajuca, Odylio D. Aguiar

Faculty Publications

We show that the interaction of a gravitational wave with a spherical resonant-mass antenna changes the antenna's shape to that of an ellipsoid. These changes in shape always determine the direction of the incoming wave and may provide information on the wave's polarization. We present a new approach for determining the position of astrophysical sources of gravitational waves which involves fewer calculations than in earlier methods. We also show how the measured quantities relate to the energy density of the wave. © 1997. The American Astronomical Society. All rights reserved.

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Techniques For Detecting Gravitational Waves With A Spherical Antenna, Stephen M. Merkowitz, Warren W. Johnson Jan 1997

Techniques For Detecting Gravitational Waves With A Spherical Antenna, Stephen M. Merkowitz, Warren W. Johnson

Faculty Publications

We report the results of a theoretical and experimental study of a spherical gravitational wave antenna. We develop a number of techniques to deconvolve the data from a set of resonant transducers attached to the surface of a sphere to monitor the sphere’s five quadrupole modes. We show that by observing these modes, one can measure the five tensorial components of a gravitational wave. The inverse problem can then be solved and the direction of a gravitational wave can be determined. Asymmetries such as the nondegeneracy of the quadrupole modes and mistuning of the transducers are included in the model …

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Generation Of Attosecond Pulses In Macroscopic Media, Philippe Antoine, Dejan B. Milošević, Anne L’Huillier, Mette B. Gaarde, Pascal Salières, Maciej Lewenstein Jan 1997

Generation Of Attosecond Pulses In Macroscopic Media, Philippe Antoine, Dejan B. Milošević, Anne L’Huillier, Mette B. Gaarde, Pascal Salières, Maciej Lewenstein

Faculty Publications

We describe theoretically the generation of ultrashort (subfemtosecond) pulses using high-order harmonics of a laser pulse with a time-dependent degree of ellipticity. The single-atom response is calculated by using a low-frequency strong-field approximation. Propagation effects are taken into account using a method going beyond the slowly varying envelope approximation. Propagation modifies significantly the results obtained in the single-atom response and, in certain conditions, makes the generation of one attosecond pulse possible. We discuss prospects for the observation of these ultrashort pulses. © 1997 The American Physical Society.

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