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Use Of Geographic Information System Technology To Assess Vulnerability To Shallow Groundwater Contamination., Brenda G. Bruner Jan 1996

Use Of Geographic Information System Technology To Assess Vulnerability To Shallow Groundwater Contamination., Brenda G. Bruner

LSU Historical Dissertations and Theses

Geographic Information System (GIS) technology was used to develop a local scale screening procedure for assessing shallow ground water's vulnerability to nitrate contamination. The procedure was based on the spatial distribution of ten key physical and chemical properties of soils. Both flow characteristics and attenuation capabilities of soils were incorporated into the assessment. Land surface areas were classified by the GIS to show the level of vulnerability present at a site as a result of existing natural conditions. The procedure produced a Vulnerability Index (VI), and resulted in VI ranging from 4.98 to 6.72 for the study area (with ten …

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Synthesis, Molecular Characterization And Physical Behavior Of Novel Polymers And Polymer Blends: Poly(Aryl Ether)Sulfones, Labeled Poly(Gamma-Stearyl-Alpha, L-Glutamate) And Poly(Gamma-Stearyl-Alpha, L-Glutamate)/Polyethylene Blends., Frederick Harald Roos Jan 1996

Synthesis, Molecular Characterization And Physical Behavior Of Novel Polymers And Polymer Blends: Poly(Aryl Ether)Sulfones, Labeled Poly(Gamma-Stearyl-Alpha, L-Glutamate) And Poly(Gamma-Stearyl-Alpha, L-Glutamate)/Polyethylene Blends., Frederick Harald Roos

LSU Historical Dissertations and Theses

The structures of a number of novel poly(aryl ether) sulfones (nitro, aminomethyl, methyl and ethyl derivatives), which have applications as separation membranes, were determined unequivocally for the first time by applying sophisticated two-dimensional nuclear magnetic resonance (NMR) methods. The degree of substitution (DS) was found to vary among the products from 0.1 percent to about 2 percent (DS: nitro, 2.0; amino, 0.11; aminomethyl, 0.76; methyl, 2.12; ethyl, 2.05). Poly($\gamma$-stearyl-$\alpha$,L-glutamate), PSLG, is a "fuzzy rod" polymer composed of a central backbone that can exist as an $\alpha$-helix. This backbone, a polypeptide, is hydrophilic. The stearyl side chains (the "fuzzy" part of …

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The Effects Of Analytic Reading Skills On Sixth Graders' Ability To Solve Mathematical Story Problems., Linda Hale Eilers Jan 1996

The Effects Of Analytic Reading Skills On Sixth Graders' Ability To Solve Mathematical Story Problems., Linda Hale Eilers

LSU Historical Dissertations and Theses

The purpose of the present study was to determine the effects of two levels of instructional treatment on sixth graders' ability to solve mathematical story problems. The two levels of instructional treatment were instruction in the use of graphic organizers in conjunction with specific analytic reading skills and instruction in specific analytic reading instruction alone. These were compared to the absence of either treatment. The steady decline in students' scores on measures of ability to read and solve story problems over the past decade prompted research in three sixth-grade public school classes in northeast Louisiana. The study employed an experimental/control, …

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Breeding Ecology Of Songbirds In Bottomland Hardwood Forests Of Louisiana., Keith Ouchley Jan 1996

Breeding Ecology Of Songbirds In Bottomland Hardwood Forests Of Louisiana., Keith Ouchley

LSU Historical Dissertations and Theses

I examined productivity, survivorship and nest-site habitat characteristics of small terrestrial landbirds breeding in bottomland hardwood forest study sites in Louisiana. Bottomland hardwood forests are the dominate ecosystem of riverine floodplains in the southeastern United States, and these forests support a diverse bird community. Over 80 percent of this forest type has been lost, primarily due to agricultural clearing, and the relative abundance of many bird species that breed in these forests has also declined. The outcomes of 790 nests of 33 species were determined. For most species, productivity was greater in large forest tracts than in small tracts. Predation …

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Reflection On Teaching: An Ethnographic Study Of Preservice Teachers' Beliefs And Practices., Thomasine Haskins Mencer Jan 1996

Reflection On Teaching: An Ethnographic Study Of Preservice Teachers' Beliefs And Practices., Thomasine Haskins Mencer

LSU Historical Dissertations and Theses

The purpose of this study was to explore the relationship between preservice teachers' expressed beliefs, their practices, and how they described the two. Particular emphasis was given to factors that influenced the preservice teachers' expectations of students. The preservice teachers were in the graduate year of a five year teacher education program that embraced reflective practice. In many ways, the two preservice teachers conformed to the mold of the typical American teacher in that they were middle class, Anglo Saxon, females who were high achievers from small towns. However, the pair differed in their experiences with diversity. The preservice teachers' …

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The Bioeconomics Of Recirculating Aquaculture Systems, Richard F. Kazmierczak Jan 1996

The Bioeconomics Of Recirculating Aquaculture Systems, Richard F. Kazmierczak

LSU Agricultural Experiment Station Reports

No abstract provided.

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School Social Climate And Individual Student Achievement In Rural High Schools., Leslie Faye Jones Jan 1996

School Social Climate And Individual Student Achievement In Rural High Schools., Leslie Faye Jones

LSU Historical Dissertations and Theses

This study examined the relationship of individual student achievement with four variables--school social climate, race, gender, and socioeconomic status. Each of these variables was expected to be significantly related to student achievement. Student achievement was measured by the LEAP sores (averages of mathematics, language arts, and writing components of the test). School social climate was measured by the Brookover (1969) school social climate questionnaire. Researchers have searched for years for an explanation of the differences in student achievement levels. The differences in student achievement levels were noted as early as the 1800's, and many studies have been done linking various …

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Amorphization And Fracture In Silicon Selenium(2) Nanowires: Molecular-Dynamics Simulations On Parallel Computer Architectures., Wei Li Jan 1996

Amorphization And Fracture In Silicon Selenium(2) Nanowires: Molecular-Dynamics Simulations On Parallel Computer Architectures., Wei Li

LSU Historical Dissertations and Theses

The primary goal of this dissertation is to investigate the structural and mechanical properties and dynamical fracture in SiSe$\sb2$ nanowires using the molecular-dynamics (MD) simulation technique. The present work is the first study of SiSe$\sb2$ nanowires. Large-scale simulations reported in this thesis are carried out with parallel multiresolution schemes for the long-range Coulomb and the three-body covalent potentials. The multiresolution scheme reduces the computational complexity from O(N$\sp2$) to O(N). Using an effective interatomic potential containing both 2- and 3-body interactions, MD simulations are performed for SiSe$\sb2$ nanowires composed of finite (1-64) number of chains. Under small uniaxial strain, the nanowires …

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Robust Sensor Fusion Algorithms: Calibration And Cost Minimization., Richard Ree Brooks Jan 1996

Robust Sensor Fusion Algorithms: Calibration And Cost Minimization., Richard Ree Brooks

LSU Historical Dissertations and Theses

A system reacting to its environment requires sensor input to model the environment. Unfortunately, sensors are electromechanical devices subject to physical limitations. It is challenging for a system to robustly evaluate sensor data which is of questionable accuracy and dependability. Sensor fusion addresses this problem by taking inputs from several sensors and merging the individual sensor readings into a single logical reading. The use of heterogeneous physical sensors allows a logical sensor to be less sensitive to the limitations of any single sensor technology, and the use of multiple identical sensors allows the system to tolerate failures of some of …

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Set Redundancy, The Enhanced Compression Model, And Methods For Compressing Sets Of Similar Images., Kosmas Karadimitriou Jan 1996

Set Redundancy, The Enhanced Compression Model, And Methods For Compressing Sets Of Similar Images., Kosmas Karadimitriou

LSU Historical Dissertations and Theses

Image compression is the process of reducing the number of bits required to represent an image. This can be achieved by reducing (or ideally, eliminating) various types of redundancy that exist in the imaging data. All current image compression methods are based on the same theoretical model, which targets redundancy found in individual images. However, this model ignores an additional type of redundancy that exists in sets of similar images, the "set redundancy". The source of set redundancy is the common information existing in more than one image in a set of similar images. Set redundancy can be recognized by …

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Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim Jan 1996

Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim

LSU Historical Dissertations and Theses

The U3 region of long terminal repeat (LTR) of equine infectious anemia virus (EIAV) contains transcriptional regulatory elements. To identify the elements in prototype (P), fetal donkey dermal cell-adapted (A), and two variant (V) EIAV LTRs, DNase I footprinting, gel shift, and transient gene expression assays were performed. The assays used U937 monocytic cells which can be induced into macrophages by 12-O-tetradecanoylphorbol-13-acetate (TPA). For study of AP1 sites, c-Jun/AP1 was also used. Footprinting with nuclear extracts from TPA-induced and uninduced U937 cells localized methylated DNA-binding protein (MDBP), PEA2, AP1, PU.1, and CCAAT enhancer-binding protein (C/EBP) sites as common elements in …

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Heritability Estimates For Reaction Resistance To Sweetpotato Chlorotic Leaf Distortion Caused By Fusarium Lateritium, Bong Kyoo Kim, Don R. La Bonte, Christopher A. Clark, Mario I. Buteler Jan 1996

Heritability Estimates For Reaction Resistance To Sweetpotato Chlorotic Leaf Distortion Caused By Fusarium Lateritium, Bong Kyoo Kim, Don R. La Bonte, Christopher A. Clark, Mario I. Buteler

Faculty Publications

Narrow-sense heritabilities for reaction to chlorotic leaf distortion (CLD), incited by Fusarium lateritium Nees: Fr., were estimated in sweetpotato [Ipomoea batatas (L.) Lam] by variance component analysis and parent-offspring regression. Visually rated severity reactions to CLD varied greatly among the 20 parents used to generate half-sib progeny from open- pollinated nurseries in 1990 and 1991. Progeny from each nursery were evaluated along with parents in a completely randomized design in two consecutive years. Narrow-sense heritability (h2) estimates based on variance components were moderate on an entry mean basis at 0.61 in 1990, 0.38 in 1991, and 0.33 for the two …

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Unavoidable Minors Of Large 3-Connected Binary Matroids, Guoli Ding, Bogdan Oporowski, James Oxley, Dirk Vertigan Jan 1996

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

Faculty Publications

We show that, for every integer n greater than two, there is a number N such that every 3-connected binary matroid with at least N elements has a minor that is isomorphic to the cycle matroid of K3,n, its dual, the cycle matroid of the wheel with n spokes, or the vector matroid of the binary matrix (In|Jn-In), where Jn is the n × n matrix of all ones. © 1996 Academic Press, Inc.

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Excluding A Long Double Path Minor, Guoli Ding Jan 1996

Excluding A Long Double Path Minor, Guoli Ding

Faculty Publications

The "height" of a graph G is defined to be the number of steps to construct G by two simple graph operations. Let Bn be the graph obtained from an n-edge path by doubling each edge in parallel. Then, for any minor-closed class script G of graphs, the following are proved to be equivalent: (1) Some Bn is not in script G; (2) There is a number h such that every graph in script G has height at most h; (3) script G is well-quasi-ordered by the topological minor relation; (4) There is a polynomial function p( • ) such …

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An Anticipatory Itô Formula, Hui Hsiung Kuo, Kenjiro Nishi Jan 1996

An Anticipatory Itô Formula, Hui Hsiung Kuo, Kenjiro Nishi

Faculty Publications

No abstract provided.

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Composites With Imperfect Interface, Robert Lipton, Bog D.An Vernescu Jan 1996

Composites With Imperfect Interface, Robert Lipton, Bog D.An Vernescu

Faculty Publications

New variational principles and bounds are introduced, describing the effective conductivity tensor for anisotropic two-phase heat conducting composites with interfacial surface resistance between phases. The new upper bound is given in terms of the two-point correlation function, component volume fractions and moment of inertia tensor for the surface of each heterogeneity. The new lower bound is given in terms of the interfacial surface area, component volume fractions and a scale-free matrix of parameters. This matrix corresponds to the effective conductivity associated with the same geometry but with non-conducting inclusions. The bounds are applied to theoretically predict the occurrence of size …

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On Inequivalent Representations Of Matroids Over Finite Fields, James Oxley, Dirk Vertigan, Geoff Whittle Jan 1996

On Inequivalent Representations Of Matroids Over Finite Fields, James Oxley, Dirk Vertigan, Geoff Whittle

Faculty Publications

Kahn conjectured in 1988 that, for each prime power q, there is an integer n(q) such that no 3-connected GF(q)-representable matroid has more than n(q) inequivalent GF(q)-representations. At the time, this conjecture was known to be true for q = 2 and q = 3, and Kahn had just proved it for q = 4. In this paper, we prove the conjecture for q = 5, showing that 6 is a sharp value for n(5). Moreover, we also show that the conjecture is false for all larger values of q. © 1996 Academic Press, Inc.

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Extension Sets For Real Analytic Functions And Applications To Radon Transforms, Vernor Arguedas, Ricardo Estrada Jan 1996

Extension Sets For Real Analytic Functions And Applications To Radon Transforms, Vernor Arguedas, Ricardo Estrada

Faculty Publications

The real analytic character of a function f(x,y) is determined from its behavior along radial directions fθ(s) = f(s cos θ, s sin θ) for θ ∈ E, where Ε is a "small" set A support theorem for Radon transforms in the plane is proved In particular if fθ extends to an entire function for θ ∈ Ε and ƒ (x, y) is real analytic in R2 then it also extends to an entire function in C2. © 1996, Hindawi Publishing Corporation. All rights reserved.

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Multigrid Methods For Parameter Dependent Problems, Susanne C. Brenner Jan 1996

Multigrid Methods For Parameter Dependent Problems, Susanne C. Brenner

Faculty Publications

Multigrid methods for parameter dependent problems are discussed. The contraction numbers of the algorithms are proved within a unifying framework to be bounded away from one, independent of the parameter and the mesth levels. Examples include the pure displacement and pure traction boundary value problems in planar linear elasticity, the Timoshenko beam problem, and the Reissner-Mindlin plate problem.

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The Intuitive Geometry Of Spinoza And Vermeer, Russell B. Gill Jan 1996

The Intuitive Geometry Of Spinoza And Vermeer, Russell B. Gill

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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The Spirit Of Poetry And The Importance Of Joy Shelley's Revolutionary Animism, John Freeman Jan 1996

The Spirit Of Poetry And The Importance Of Joy Shelley's Revolutionary Animism, John Freeman

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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Enacting The Tyranny Of Social Forms In Sheridan's The Rivals, Robert P. Maccubbin Jan 1996

Enacting The Tyranny Of Social Forms In Sheridan's The Rivals, Robert P. Maccubbin

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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Analytic Approximations To The Spacetime Of A Critical Gravitational Collapse, Richard H. Price, Jorge Pullin Jan 1996

Analytic Approximations To The Spacetime Of A Critical Gravitational Collapse, Richard H. Price, Jorge Pullin

Faculty Publications

We present analytic expressions that approximate the behavior of the spacetime of a collapsing spherically symmetric scalar field in the critical regime first discovered by Choptuik. We find that the critical region of spacetime can usefully be divided into a "quiescent," an "oscillatory," and a moving "transition" region. We find that in the quiescent and oscillatory regions the critical solution can be well approximated by a flat spacetime scalar field solution. A qualitative nonlinear matching of the solutions across the transition region yields the right order of magnitude for the oscillations of the discretely self-similar critical solution found by Choptuik. …

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A Passive Vibration Isolation Stack For Ligo: Design, Modeling, And Testing, Joseph Giaime, Partha Saha, David Shoemaker, Lisa Sievers Jan 1996

A Passive Vibration Isolation Stack For Ligo: Design, Modeling, And Testing, Joseph Giaime, Partha Saha, David Shoemaker, Lisa Sievers

Faculty Publications

Multiple-stage seismic vibration isolation stacks, which consist of alternating layers of stiff masses and compliant springs, can provide significant passive filtering of. ground vibration for experiments and equipment that are sensitive to mechanical noise. We describe the design, modeling and testing of a prototype of a stack suitable for use in the Laser Interferometer Gravitational-wave Observatory (LIGO). This is a four-stage elastomer (spring) and stainless steel (mass) stack, consisting of a table resting on three separate legs of three layers each. The viscoelastic properties of elastomer springs are exploited to damp the stack's normal modes while providing rapid roll-off of …

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Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren Jan 1996

Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren

LSU Historical Dissertations and Theses

Treatment of municipal and rural wastewater using subsurface flow constructed wetlands (SFCW's) is growing in popularity. These systems often consist of an excavated cell containing 2-3 in. rock with the wastewater level maintained below the media surface. A SFCW is a natural form of wastewater treatment which removes organics and nutrients based on the attached growth of microorganisms on crushed rocks where biological reactions take place. The currently accepted design procedure is based on the first order plug flow model, although tracer studies have shown that flow conditions are not well represented by the plug flow condition. This design rationale …

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Crystal Plasticity Model With Back Stress Evolution., Wei Huang Jan 1996

Crystal Plasticity Model With Back Stress Evolution., Wei Huang

LSU Historical Dissertations and Theses

In this work, two backstress models and a modified yield criterion for crystalline materials are proposed. The proposed work is for the identification of texture development in metals when subjected to large deformation processes such as rolling, extrusion, stamping and deep drawing, etc. These models are incorporated into a numerical procedure similar to the approaches by Asaro (1983), Peirce et al. (1983), Nemat-Nasser (1983), and Rashid and Nemat-Nasser (1992). Also, similar to their approaches, a two-dimensional crystal structure is used for a feasibility study of the model by solving a simple shear problem. More importantly, the proposed formulations are strain …

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Le Temps Dans Les Oeuvres De Jorge Luis Borges, Edouard Glissant Et Saint-John Perse., Valerie Irene Loichot Jan 1996

Le Temps Dans Les Oeuvres De Jorge Luis Borges, Edouard Glissant Et Saint-John Perse., Valerie Irene Loichot

LSU Historical Dissertations and Theses

This dissertation compares conceptions of time as they appear in the works of Jorge Luis Borges, Edouard Glissant and Saint-John Perse. It attempts to stage a series of encounters among these writers, encounters or "relatings" in the sense of correlation and narration. The first relation is that expressed by Paul Ricoeur, who states that time becomes human only when it is articulated in narration and narration becomes human only when it describes the features of temporal experience. The second relation, or set of relations, occurs in the plural, interrupted, yet interconnected topos of the Americas. Through an analysis of the …

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Walker Percy's Return To The Feminine., John Patrick Zmirak Jr Jan 1996

Walker Percy's Return To The Feminine., John Patrick Zmirak Jr

LSU Historical Dissertations and Theses

What has been lacking in the corpus of interpretation of Walker Percy's work is a synthesis of approaches, a reading of the novels that unites the philosophical, psychological, theological, and linguistic insights that have accrued over three decades of criticism, and applies them to the vexing question of sexuality within his novels. In the present work, Percy's four central, non-satiric novels, The Moviegoer, The Last Gentleman, Lancelot and The Second Coming, are analyzed in the light of the Christian allegorical tradition, which employs sexual categories to explicate the meta-physical order, and to inform sexuality with meaning. In each of Percy's …

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The Generalized Kompaneets Equation., Kunyang Wang Jan 1996

The Generalized Kompaneets Equation., Kunyang Wang

LSU Historical Dissertations and Theses

In the dissertation, the generalized Kompaneets equation$${\partial u\over\partial t}={1\over\beta(x)}\lbrack\alpha(x)(u\sb{x}+ku+F(x,u))\rbrack\sb{x}$$(for $x,t>0)$ is studied. For the linear case, when $F\equiv0,$ a complete theory is given. A brief discussion is carried for the nonlinear case when $F(x,u)=f(x)g(u).$. For the following equation,$$v\sb{t}=\varphi(y,v\sb{y})v\sb{yy}+\psi(y,v,v\sb{y}),$$Goldstein and Lin's result is extended to degenerate case. Also, for the following linear operator,$$Au=\alpha(x)u\prime\prime+\beta(x)u\prime$$(for $x\in \lbrack 0,$ 1)), Clement and Timmermans' result is extended to the case of discontinuous coefficients $\alpha$ and $\beta$.

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Some Lifting Problems In Arithmetic Equivalence., Nancy C. Colwell Jan 1996

Some Lifting Problems In Arithmetic Equivalence., Nancy C. Colwell

LSU Historical Dissertations and Theses

The main theorem in this dissertation provides a partial answer to the following question: Given a $\doubz\sb{p}$-extension $F{\sb\infty} /F$ and a finite extension $K/F$, where F is a number field and p a prime number, to what extent does the K-splitting behavior the prime ideals of F determine the Iwasawa invariants of the $\doubz\sb{p}$-extension $K{\cdot}F{\sb\infty}/K$. The answer is that if two fields K and L are arithmetically equivalent over F, then $K{\cdot}F{\sb\infty} /K$ and $L{\cdot}F{\sb\infty} /L$ have exactly the same Iwasawa invariants for any $\doubz\sb{p}$-extension $F{\sb\infty} /F$, so long as p is not an exceptional divisor for K and L …

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