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Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene Jan 1993

Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene

LSU Historical Dissertations and Theses

Hydrologic modelling can be enhanced and improved through the utilization of a Geographic Information System (GIS). Information can be stored and analyzed by the tools available within a GIS to create a spatial database that realistically represents a watershed for hydrologic modelling. This study presents an approach whereby the data available in the GIS determine the modelling strategy. The soil, topography and land cover data for the watershed were analyzed with the spatial analysis tools of a GIS to determine the hydrologic response areas. The coordinate values that define the locations and boundaries of features in the GIS were used …

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In Situ Determination Of Capillary Pressure And Relative Permeability Curves Using Well Logs., Adel Afifi Ibrahim Jan 1993

In Situ Determination Of Capillary Pressure And Relative Permeability Curves Using Well Logs., Adel Afifi Ibrahim

LSU Historical Dissertations and Theses

A pressure profile obtained from the formation tester defines the wettability, free water level, and hydrocarbon and water densities as well as the capillary pressure above the free water level. Correlating the pressure values to the water saturation values determined from the resistivity logs results in a capillary pressure/water saturation, $\rm P\sb{c}(S\sb{w}),$ curve characteristic of the reservoir. A relative permeability curve then can then be derived from this $\rm P\sb{c}(S\sb{w})$ curve using empirical relationships. This approach was tested in the laboratory using an eight-foot vertical sandstone core to simulate the formation. The core was fitted with electrode arrays, and resistivity …

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High-Temperature High-Pressure Carbon Dioxide Removal From Coal Gas., Arpaden Silaban Jan 1993

High-Temperature High-Pressure Carbon Dioxide Removal From Coal Gas., Arpaden Silaban

LSU Historical Dissertations and Theses

The noncatalytic gas-solid reaction between CO$\sb2$(g) and CaO(s) to form CaCO$\sb3$(s) has been studied at high temperature and high pressure (HTHP) using a thermobalance reactor. This reaction could serve as the basis for a HTHP process for the separation of CO$\sb2$ from coal-derived gas. The kinetics of the calcination and carbonation reactions were studied as a function of temperature, pressure, CO$\sb2$ concentration, and background gas composition. Three sorbent precursors which produced CaO having a wide range of structural properties were selected for detailed kinetic studies. They were (i) reagent grade calcium carbonate, (ii) reagent grade calcium acetate, and (iii) commercial …

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A Blackboard Integration Of Manufacturing Databases Using An Intelligent Interface., David Anderson Koonce Jan 1993

A Blackboard Integration Of Manufacturing Databases Using An Intelligent Interface., David Anderson Koonce

LSU Historical Dissertations and Theses

The explosion of computer applications into the world of manufacturing along functional lines has produced the often mentioned "islands of automation." Although many issues and problems are involved in interfacing and integrating the databases that serve these applications, we can extract valuable data from these independent systems to provide important information to decision makers. This research resulted in the development of MIMIR (Multiple Integrated Manufacturing Information Resources), a decision support system based upon the blackboard architecture. The blackboard architecture extends the common expert system design to include multiple expert systems, termed Knowledge Sources (KS's), which combine to solve problems too …

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Remagnetization Of Carbonates In The Appalachian Basin., Barbara Saffer Jan 1993

Remagnetization Of Carbonates In The Appalachian Basin., Barbara Saffer

LSU Historical Dissertations and Theses

Paleomagnetic and rock magnetic data from two transects of southern and northern Appalachian Basin carbonates demonstrate different patterns of Late Paleozoic remagnetization and magnetite concentration. Samples were collected in Ordovician and Mississippian carbonates of Tennessee and Alabama and in Devonian carbonates of New York and Ontario. In the southern basin, Paleozoic carbonates of the Nashville Dome and of the fold-thrust belt near Chattanooga were remagnetized during the Late Paleozoic Kiaman period. These remagnetized carbonates contain more magnetite than do unremagnetized carbonates in the intervening basin. The unremagnetized carbonates demonstrate only a present field magnetization except for one Mississippian site in …

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Chemical Vapor Deposition To Titanium Dioxide Thin Films., Qingming Zhang Jan 1993

Chemical Vapor Deposition To Titanium Dioxide Thin Films., Qingming Zhang

LSU Historical Dissertations and Theses

TiO$\sb2$ thin films have been prepared by the thermal decomposition of titanium tetra-isopropoxide (TTIP) in two low pressure chemical vapor deposition (LPCVD) reactors. The two reactors are the vertical tube hot-wall reactor and the stagnation point flow single-wafer cold-wall reactor. The effects of TTIP partial pressure, substrate temperature, gas flow rate, and reactor pressure on the growth rate of TiO$\sb2$ film were examined. Aerosol formation, wall effects, the effect of water content, and the effect of reactor geometry were also investigated. The experiments were performed in the substrate temperature range 225-400$\sp\circ$C, inlet TTIP partial pressure range $6.4\times10\sp{-4}$ $-$ 0.4 torr, …

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Visual Transformations In Symbolic Elementary Algebra., Thomas Harold Awtry Jan 1993

Visual Transformations In Symbolic Elementary Algebra., Thomas Harold Awtry

LSU Historical Dissertations and Theses

Competence in algebra requires knowledge of parsing and transformations. The parsing component specifies the structure of algebraic expressions based on conventional operation hierarchies. The transformational component specifies the real number properties used to transform algebraic expressions into equivalent forms. In standard models of mathematical cognition, both components are conceived as strictly propositional domains (e.g., Anderson, 1983a). Kirshner (1989b) demonstrated that parsing knowledge initially is apprehended in a visual (non-propositional) modality. This dissertation extends that visual analysis beyond parsing to the transformational component. It is proposed that transformations range on a continuum from highly propositional (e.g., x(y$\sp{-1}) = ({\rm x \over …

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An Algorithm For Supervisory Multivariable Constrained Optimization Of Industrial Processes., William E. Daniel Jr Jan 1993

An Algorithm For Supervisory Multivariable Constrained Optimization Of Industrial Processes., William E. Daniel Jr

LSU Historical Dissertations and Theses

An algorithm is presented for supervisory optimization of industrial processes that combines the minimization of operating costs with process operating constraints. The supervisory algorithm manipulates the set points of a lower-level control system and the set points are updated at long enough intervals of time so that the process reaches steady state between set point updates. This steady state assumption greatly simplifies the algorithm computations and, more importantly, significantly reduces the effort required for process identification. This dissertation develops the algorithm and then presents results from its application to a simulated distillation train and reactor feed network. In both applications, …

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Mathematical Model Of Hairy Root Growth., Seungdo Kim Jan 1993

Mathematical Model Of Hairy Root Growth., Seungdo Kim

LSU Historical Dissertations and Theses

Hairy roots produce secondary metabolites which have been used as specialty chemicals. The mathematical models of hairy root growth kinetics can guide the design and scale-up of root cultures. An unstructured segregated and a chemically structured segregated models for hairy growth kinetics are formulated with rules of root branching processes. The deterministic branching rule and the stochastic branching rule are studied. For the deterministic rule where two branching parameters are assumed constant, the number of tips can be obtained by solving a linear difference equation. The conceptual framework established for the deterministic rule is used to formulate a stochastic rule …

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Pollutant Transport In Buoyancy Driven Atmospheric Flows., Youn-Seo Koo Jan 1993

Pollutant Transport In Buoyancy Driven Atmospheric Flows., Youn-Seo Koo

LSU Historical Dissertations and Theses

Due to the complexity of some buoyancy driven atmospheric flows, it is sometimes not possible to accurately predict pollutant transport on the basis of sparse wind field measurements. A possible solution is mathematical modelling of both the flow and pollutant transport. In order to overcome shortcomings of the conventional E-$\epsilon$ model such as defining proportionality coefficients (c$\sb{\rm m},$ c$\sb{\rm h})$ and to develop a more general model of stratified environmental flows, a modified E-$\epsilon$ model was proposed through use of the algebraic stress model including wall proximity effects. The resulting model was compared herein to data and higher order simulations …

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Mobilization Of A Hydrophobic Organic Compound Using Surfactant For Soil Washing., Minwen Liu Jan 1993

Mobilization Of A Hydrophobic Organic Compound Using Surfactant For Soil Washing., Minwen Liu

LSU Historical Dissertations and Theses

Soil washing using surfactants is a promising alternative for the conventional pump-and-treat method of removing hydrophobic organic compounds. The interactions and the transport of the chemicals have been studied by batch and column experiments. Sodium dodecylsulfate (SDS), an anionic surfactant, and anthracene, a hydrophobic organic, were chosen as the representative surfactant and contaminant, respectively. Fine sand and native soil were used as formation media. The experimental results indicated that the maximum loss of SDS on native soil from the solution was observed when the aqueous SDS concentration was in the region of the critical micelle concentration, and this loss was …

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A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar Jan 1993

A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar

LSU Historical Dissertations and Theses

The path-dependent and nonlinear behavior of metallic materials subjected to cyclic loading is modelled using the proposed hardening rule. It uses mainly two surfaces, a yield and a limit surface and includes the memory effects through a separate surface called the memory surface which is obtained from a maximum stress criterion. The model considers the facts that the motion of the center of the yield surface in the stress space is mainly governed by the direction of the deviatoric stress rate and that the uniqueness of the solution requires nesting of the two surfaces. The model proposed satisfies both conditions …

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Embedding Schemes For Interconnection Networks., David Aloys Hoelzeman Jan 1993

Embedding Schemes For Interconnection Networks., David Aloys Hoelzeman

LSU Historical Dissertations and Theses

Graph embeddings play an important role in interconnection network and VLSI design. Designing efficient embedding strategies for simulating one network by another and determining the number of layers required to build a VLSI chip are just two of the many areas in which graph embeddings are used. In the area of network simulation we develop efficient, small dilation embeddings of a butterfly network into a different size and/or type of butterfly network. The genus of a graph gives an indication of how many layers are required to build a circuit. We have determined the exact genus for the permutation network …

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The Congruence Extension Property, The Ideal Extension Property, And Ideal Semigroups., Karen Dommert Aucoin Jan 1993

The Congruence Extension Property, The Ideal Extension Property, And Ideal Semigroups., Karen Dommert Aucoin

LSU Historical Dissertations and Theses

A semigroup has the congruence extension property (CEP) provided that each congruence on each subsemigroup of S extends to a congruence on S. The ideal extension property (IEP) for semigroups is defined analogously. A characterization of commutative semigroups with IEP is given in terms of multiplicative conditions within and between the archimedean components of the semigroup. A similar characterization of commutative semigroups with CEP is sought. Toward this end, archimedean semigroups with CEP are characterized in terms of multiplicative structure and a number of necessary conditions on multiplication between the archimedean components of a commutative semigroup with CEP are established. …

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Split Abelian Extensions Of Calgebras., Mark Andrew Curole Jan 1993

Split Abelian Extensions Of Calgebras., Mark Andrew Curole

LSU Historical Dissertations and Theses

It is shown that the C* algebra of a groupoid with Haar system has a natural split abelian extension. For a split abelian extension of a C* algebra it is shown that all representations of the original algebra extend to the split abelian extension. Under a reasonable assumption it is shown that states extend to a split abelian extension. Definitions for quasi-invariant and ergodic measures are given for split abelian extension of C* algebras, and it is shown when the split abelian extension is the natural extension of the C* algebra of a groupoid with Haar system that these definitions …

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Stress-Strain Analysis Of Adhesive-Bonded Composite Single-Lap Joints Under Various Loadings., Chihdar Yang Jan 1993

Stress-Strain Analysis Of Adhesive-Bonded Composite Single-Lap Joints Under Various Loadings., Chihdar Yang

LSU Historical Dissertations and Theses

The objective of this study is to develop mathematical relations for stress and strain distributions of adhesive-bonded single-lap joints under cylindrical bending and tension. Based on the Theory of Mechanics of Composite Materials and Anisotropic Laminated Plate Theory, elastic models are proposed to predict the stress-strain distributions of the laminates and the adhesive under cylindrical bending and tension. A simplified elastic-plastic model is also recommended for the case of tension loading. For each case, the Laminated Anisotropic Plate Theory is first used in the derivation of the governing equations of the two bonded laminates. The entire coupled system is then …

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A Restoration-Based Model For Materials Management In A Global Manufacturing Environment., Gary Wayne Clendenen Jan 1993

A Restoration-Based Model For Materials Management In A Global Manufacturing Environment., Gary Wayne Clendenen

LSU Historical Dissertations and Theses

Globalization of manufacturing along with increased competition has made effective planning and control more important than ever. At the same time, it is more difficult than ever to achieve effective planning and control due to larger leadtimes and shorter product life cycles. The objective of this research is to explore the importance of control strategy on materials management in global manufacturing networks. Control strategies in common use and others that have recently been proposed in the literature are reviewed and classified along a push/pull gradient. It is shown that one of them, the restoration control strategy, can be used to …

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Voices From Home: Familial Bonds In The Works Of Horton Foote (1916- )., Marion Dean Castleberry Jan 1993

Voices From Home: Familial Bonds In The Works Of Horton Foote (1916- )., Marion Dean Castleberry

LSU Historical Dissertations and Theses

For more than half a century Horton Foote has been regarded as one of America's foremost dramatists. Born and reared in Wharton, Texas, he wrote his first play Wharton Dance in 1939, at the age of twenty-three, and gained his first Broadway production, Only The Heart, in 1944. His success as a playwright led to television, for which he wrote some of his finest dramas, and finally to a distinguished career in film. Foote has received numerous awards for his plays and screenplays, including Academy Awards for To Kill A Mockingbird (1962) and Tender Mercies (1983) and an Academy Award …

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An Examination Of The Spontaneously Generated And Retold Narratives Produced By Gifted/Learning-Disabled Adolescents From An Integrated Perspective Of Language Development., Phebe Archon Hayes Jan 1993

An Examination Of The Spontaneously Generated And Retold Narratives Produced By Gifted/Learning-Disabled Adolescents From An Integrated Perspective Of Language Development., Phebe Archon Hayes

LSU Historical Dissertations and Theses

Few studies have examined the narrative abilities of gifted children with learning disabilities. This study investigated the ability of eighth-grade gifted children with learning disabilities (gifted/LD) to produce oral and written narratives by comparing their stories to those produced by gifted peers with no learning deficits (nonLD/gifted). It was hypothesized that evidence of difficulty generating the stories relative to the macrostructure (organization of ideas across sentences) and the microstructure (organization of ideas within sentences) would be exhibited by the gifted/LD population. Twenty, 13-year-old eighth-graders served as subjects in the present investigation. All were identified as gifted by their local school …

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Development And Evaluation Of An Expert System Approach To Uneven-Aged Management Of Loblolly-Shortleaf Pine Stands In The West Gulf Region., Alfredo Baptista Lorenzo Jan 1993

Development And Evaluation Of An Expert System Approach To Uneven-Aged Management Of Loblolly-Shortleaf Pine Stands In The West Gulf Region., Alfredo Baptista Lorenzo

LSU Historical Dissertations and Theses

Forest managers expend significant time and effort seeking, organizing, and synthesizing information relevant to making effective forestry decisions. Oftentimes, they must rely on the knowledge and experience of human experts, a resource that is in short supply, requires many years to acquire, and is concentrated in a few individuals. This research task suggests expert systems as one viable solution to the problems of technology transfer and automating and maintaining expertise in consistent and usable form. Expert systems are practical computer programs which solve problems that were previously considered only solvable by human expertise. The expert system developed in this research, …

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Predicting The Movement And Retention Of Pesticides In Soils: Physical And Chemical Nonequilibrium Modeling Approaches., Liwang Ma Jan 1993

Predicting The Movement And Retention Of Pesticides In Soils: Physical And Chemical Nonequilibrium Modeling Approaches., Liwang Ma

LSU Historical Dissertations and Theses

Atrazine retention and transport in a highly aggregated Sharkey clay soil were investigated through kinetic batch experiments, miscible displacement (column transport), and mathematical modeling. Batch results indicated that atrazine retention was kinetic and adsorption-desorption was hysteretic. Adsorption and desorption isotherms were well described using the Freundlich equation (S = KC$\sp{\rm N}).$ Fitted Freundlich K was a function of reaction time and initial atrazine input concentrations, whereas fitted N was only affected by reaction time. Desorption hysteresis was quantified by the maximum difference between adsorption and desorption isotherms, and showed a linear increase with reaction time. Atrazine adsorption kinetics was successfully …

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Use Of The History Of Science In A Nonscience Majors Course: Does It Affect Students' Understanding Of The Nature Of Science?, Linda Easley Roach Jan 1993

Use Of The History Of Science In A Nonscience Majors Course: Does It Affect Students' Understanding Of The Nature Of Science?, Linda Easley Roach

LSU Historical Dissertations and Theses

In response to a call for more research into using the history of science to teach the nature of science, a call for curriculum materials for inclusion of the nature of science in undergraduate nonscience majors courses, and in keeping with the nature of science described in the literature, interactive nature-of-science historical vignettes were utilized in a quantitative and qualitative investigation. Interactive nature-of-science historical vignettes employ the interrupted story form and binary opposites involving conflict to generate student participation and spark discussion about the nature of science. They were utilized as an experimental technique in a university level, introductory nonscience …

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Mathematics And Gender: A General History Of Recent Research And Common Perceptions., Mary E. Reeves Jan 1993

Mathematics And Gender: A General History Of Recent Research And Common Perceptions., Mary E. Reeves

LSU Historical Dissertations and Theses

In the last two decades a tremendous volume of research data has been collected about differences between female and male students in mathematics. But although the amount of data collected has been large, there have been few conscious attempts to understand this data in social, economic, technological, and political terms. This history of academic research on gender differences connects the explosion of academic interest in the 1970s and 1980s with the launch of Sputnik in 1957 and the sense of technological crisis that pervades mathematics education and popular consciousness. The emergence of "Women's Lib" and interest in gender equity in …

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Neo-Hamiltonian Republicans And Military Reform In The Progressive Era: 1898-1912., Ronald James Barr Jan 1993

Neo-Hamiltonian Republicans And Military Reform In The Progressive Era: 1898-1912., Ronald James Barr

LSU Historical Dissertations and Theses

The Spanish-American War changed the course of American history. In a few months the United States acquired a colonial empire and adopted a policy of overseas involvement that greatly altered future world events. The political victory of a few military reformers and politicians, who endorsed Social Darwinism, over those who upheld the ideas of Jefferson and Jackson, destroyed the international isolation of the American republic. No matter what successive political administrations claimed, they inherited substantial overseas commitments. The group that engineered this profound change in American foreign and defence policy were led by Elihu Root, John Hay, Leonard Wood, Alfred …

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Inhomogeneous Boundary Effects In Semiconductor Quantum Wires, G. Y. Hu, R. F. O'Connell Dec 1992

Inhomogeneous Boundary Effects In Semiconductor Quantum Wires, G. Y. Hu, R. F. O'Connell

Faculty Publications

Boundary effects play an essential role in determining the physical properties of semiconductor quantum wires. Additional features come into play when one considers inhomogeneous boundaries, i.e. wires whose widths are functions of distance along the length of the wire. The authors show that, in the adiabatic approximation (which assumes that the boundary potential fluctuation effects, or equivalently, the variations in the wire width, occur on a scale much larger than the inverse of Fermi wavelength), the boundary problem for a quantum wire is equivalent to a one-dimensional Schrodinger equation along the wire with: (i) an effective potential provided by the …

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Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh Nov 1992

Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh

Faculty Publications

We show that for any accessible class of matroids of bounded width, the Tutte polynomial is computable in polynomial time. © 1992.

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Connectivity Of Submodular Functions, James Oxley, Geoff Whittle Aug 1992

Connectivity Of Submodular Functions, James Oxley, Geoff Whittle

Faculty Publications

The notion of connectivity for submodular functions was introduced by Cunningham. This paper relates the connectivity of such a function f to that of certain submodular functions which are derived from f. In particular, we prove a generalisation of the well-known matroid result that, for every element x of a connected matroid M, either the deletion or contraction of x from M is connected. © 1992.

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The Unbearable Heaviness Of Politics: Milan Kundera On Aesthetics, Being And Political Consciousness, Sidney S. Fazio May 1992

The Unbearable Heaviness Of Politics: Milan Kundera On Aesthetics, Being And Political Consciousness, Sidney S. Fazio

LSU Historical Dissertations and Theses

The work of Czech novelist Milan Kundera provides some interesting philosophical and aesthetic reflections upon the nature of human existence. Kundera strives to make concrete discoveries about human experiences through his novels. The role of the novel in revealing concrete existence presents one with a unique means to ponder political questions. Kundera's aesthetic and political philosophy arises from his distinct world view and aesthetic theory, based on three overarching premises, which insist that the most important goals for a novelist (or anyone) are: to make discoveries about existence; to ask questions without offering answers; and to express the fundamental ambiguity …

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Faculty Senate Resolution 91-04, Louisiana State University And Agricultural & Mechanical College Feb 1992

Faculty Senate Resolution 91-04, Louisiana State University And Agricultural & Mechanical College

LSU Faculty Senate Publications

Faculty Senate Resolution on the admission standards and honor committee, adopted on February 18, 1992.

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Gumbo Yearbook, Class Of 1992, Louisiana State University And Agricultural And Mechanical College Jan 1992

Gumbo Yearbook, Class Of 1992, Louisiana State University And Agricultural And Mechanical College

Gumbo Yearbook

The Gumbo yearbook chronicles the entire academic year at LSU. In words and especially photos, the Gumbo shows the people, places, and events that make each year unique. In addition to formal portraits of schools and departments, the book contains hundreds of snapshots of students with their friends and dozens of pages showcasing organizations.

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