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Chromatographic Peak Shape Analysis And Modeling., Mark Stephen Jeansonne Jan 1990

Chromatographic Peak Shape Analysis And Modeling., Mark Stephen Jeansonne

LSU Historical Dissertations and Theses

Various aspects of chromatographic peak quantitation and shape characterization are investigated in detail for single and overlapping chromatographic peaks. From the viewpoint of providing better quantitation of real chromatographic data while minimizing computational complexity, the results presented should be easily incorporated into existing routine chromatographic data analysis regimes. Three topics applicable to modern chromatographic data analysis are considered. First, progress in the application of the exponentially modified Gaussian (EMG) function to chromatography is reviewed. The review covers the following areas: (1) equations derived from the model, (2) studies of inherent errors in the quantitation of chromatographic peaks via use of …

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Attributions Of Teachers And Students In Middle School Science Classrooms., Lennie Holomon Rhys Jan 1990

Attributions Of Teachers And Students In Middle School Science Classrooms., Lennie Holomon Rhys

LSU Historical Dissertations and Theses

The purpose of the present study was to examine: (a) teachers' notions about their students, (b) students' notions about themselves and learning, and (c) important factors that characterize, and possibly influence, these notions. The investigation was based on attribution theory, which proposes a framework for ascribing causes of a person's behavior, given that person's belief system. In this study, five notions, or attributions, were specified: attachment, concern, satisfied, indifferent, and rejection, and were expressed in three forms: oral, written, and behavioral. Subjects included three sixth-grade science teachers, three eighth-grade science teachers, and one science class from each teacher's schedule. For …

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Assessing The Potential Impact Of Sugarcane Varieties And Predation On Diatraea Saccharalis (F.) Populations In Southern Louisiana., Ricardo Tomas Bessin Jan 1990

Assessing The Potential Impact Of Sugarcane Varieties And Predation On Diatraea Saccharalis (F.) Populations In Southern Louisiana., Ricardo Tomas Bessin

LSU Historical Dissertations and Theses

To facilitate a better understanding of how varietal resistance and predation affect area-wide sugarcane borer populations, several studies were undertaken before the development of a simulation model. The first study was a 3-year investigation into the compatibility and contributions of varietal resistance, arthropod predation and insecticide toward sugarcane borer control. Insecticides were shown to be the predominant management factor preventing plant injury, but varietal resistance appeared nearly as important in terms of sugarcane borer population regulation in sugarcane. The next study assessed a moth production index in addition to the percentage of bored internodes as a tool for quantifying varietal …

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Stress Begins In Kindergarten: A Look At Behavior During Standardized Testing., Pamela Owen Fleege Jan 1990

Stress Begins In Kindergarten: A Look At Behavior During Standardized Testing., Pamela Owen Fleege

LSU Historical Dissertations and Theses

Children's behavior during standardized achievement testing was explored through a qualitative study of two kindergarten classrooms. The subjects were 36 kindergarten children (10 Black, 26 white; 17 males, 19 females). Data were collected through observations in the classrooms; interviews with children, teachers, and principals; and video taping of the children before, during, and after standardized achievement testing. Findings indicated an increase in behaviors reported to be stress related during the testing situation and a decrease in those behaviors following the testing period. Other frequently observed behaviors included copying and calling out answers during the administration of the test. In addition, …

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A Functional Approach To Model Management., Lijen Ko Jan 1990

A Functional Approach To Model Management., Lijen Ko

LSU Historical Dissertations and Theses

A model management system (MMS) is a computer-based system which facilitates the management of a wide range of decision support models (DSMs). It is a vital component of a decision support system which helps decision makers using data and DSMs in an integrated fashion. It is desirable that an MMS is knowledge-based, flexible, independent and reflecting users' view of a DSM. In addition, an MMS must manage DSMs at both the macro and micro levels. At the macro level, DSMs are described using descriptive attributes to supply users with general problem-solving capabilities. At the micro level, the components and mathematical …

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Effects Of Rock/Cutter Friction On Pdc Bit Drilling Performance: An Experimental And Theoretical Study., Ergun Kuru Jan 1990

Effects Of Rock/Cutter Friction On Pdc Bit Drilling Performance: An Experimental And Theoretical Study., Ergun Kuru

LSU Historical Dissertations and Theses

A new mechanistic drilling model for PDC bits was derived from the balance of forces acting at the PDC cutter. The model combined the torque and the drilling rate equations, cutter's geometry and rock properties. A new understanding of frictionally generated heat between rock and PDC cutter is introduced. The numerical analysis revealed that neglecting the heat generated at the cutting surface area results in underestimation of the actual wearflat temperature by 10% to 530%, depending upon bit dull and downhole hydraulics. The example bit performance comparison made by calculating the MBP curves showed 18% reduction of drilling rate when …

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Louisiana Agriculture Magazine, Fall 1989, Lsu Agricultural Experiment Station Oct 1989

Louisiana Agriculture Magazine, Fall 1989, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Lsu General Catalog 1989-1990, Louisiana State University And Agricultural And Mechanical College Jan 1989

Lsu General Catalog 1989-1990, Louisiana State University And Agricultural And Mechanical College

LSU General Catalog

The LSU General Catalog describes all undergraduate and graduate departments and programs with degree requirements and courses offered for each one. The General Catalog includes information on registration and financial aid as well as academic services offered to all students.

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Using Expert Systems In Maintenance Monitoring And Management., Tahoomars Rastin Jan 1989

Using Expert Systems In Maintenance Monitoring And Management., Tahoomars Rastin

LSU Historical Dissertations and Theses

In this research, a model for fault diagnosis of equipment is discussed. The model discusses the use of multi-variable monitoring for a more precise means of equipment malfunction trouble shooting. Also within this model means are discussed for automatically generating work-orders. Equipments are divided into subsystems. The subsystems are broken down into sub-subgroups and further down to individual parts. Preventive maintenance techniques, along with expert system technology, are used to develope the maintenance expert system (MES). Statistical pattern recognition techniques are used as a way to describe the relationship between categories of equipment. The relationships shown here are mostly that …

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Probabilities And Climatic Patterns Of Precipitation In Louisiana, 1951-1980, R A. Muller Jan 1989

Probabilities And Climatic Patterns Of Precipitation In Louisiana, 1951-1980, R A. Muller

LSU Agricultural Experiment Station Reports

No abstract provided.

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Development Of A Karplus-Type Relationship For Solid State Deuterium Nuclear Magnetic Resonance Spectroscopy., Margaret Alice Callaghan Jackisch Jan 1989

Development Of A Karplus-Type Relationship For Solid State Deuterium Nuclear Magnetic Resonance Spectroscopy., Margaret Alice Callaghan Jackisch

LSU Historical Dissertations and Theses

This dissertation is the first application of a Karplus-type relationship to solid-state deuterium NMR spectroscopy. In particular zero-field high-resolution deuterium adiabatic demagnetization in the laboratory frame (ADLF) spectroscopy has been used to distinguish between two inequivalent deuterium positions in alpha substituted arylacetic acids. High resolution spectra with linewidths of 1-2 kHz were observed and have been used successfully to document the inequivalent positions both by single and double transition spectra. Further, small applied fields, inducing Zeeman splitting, have proven the deuterons observed to be from the transition frequencies of two different deuterons. Individual spectra are shown for all compounds included …

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Overestimation Of Basis Set Superposition Error In Molecular Dimer Correlation Potential Energy Calculations., Jia-An Yang Jan 1989

Overestimation Of Basis Set Superposition Error In Molecular Dimer Correlation Potential Energy Calculations., Jia-An Yang

LSU Historical Dissertations and Theses

It is important to remove the basis set superposition error (BSSE) from the intermolecular potential energy calculations with the counterpoise (CP) correction especially for weak intermolecular interactions. However, it has been still questioned whether the counterpoise (CP) correction overestimates the real BSSE. To answer this question is the purpose of this research. In this study, the overestimation of basis set superposition error (BSSE) by the counterpoise (CP) method has been analyzed by an approach called "localized orbital pair correlation". This approach is able to eliminate the overestimation of basis set superposition error (BSSE) for the second order potential energies. Prototype …

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Arch: A Robust Construction Heuristic For The Layout Design Of Food Processing Facilities., George Robert Baskin Jan 1989

Arch: A Robust Construction Heuristic For The Layout Design Of Food Processing Facilities., George Robert Baskin

LSU Historical Dissertations and Theses

A Robust Construction Heuristic (ARCH) represents the first attempt to develop a facilities layout design algorithm tailored to the particular solution of the food processing facility layout problem where a fluctuating product mix due to seasonality or changes in consumer demand is typical. The foundation literature for this research comes predominantly from the industrial engineering, management science, and food science fields. Construction heuristics built layouts from scratch and provided poor quality results. Robustness algorithms had no simplifying heuristics but were reported to yield potentially higher quality layouts than traditional algorithms for layout problems with fluctuating product mixes. ARCH was developed …

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Robert Floyd Kennon: Reform Governor., Doris Dorcas Carter Jan 1989

Robert Floyd Kennon: Reform Governor., Doris Dorcas Carter

LSU Historical Dissertations and Theses

This dissertation is a study of Robert Floyd Kennon, reform governor of Louisiana, from 1952-1956. Kennon was born on August 21, 1902, near Minden, Louisiana. He received his bachelor's degrees from Louisiana State University in Baton Rouge in Liberal Arts and Law in 1923 and 1925, respectively. In 1925, he began the practice of law in Minden, and was elected as mayor of the town at age twenty-three. Five years later, he sought and won, the office of District Attorney, for the Twenty-Sixth Judicial District, a position he held for ten years. He was a staff officer in Europe during …

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Barotropic Shelf Circulation Forced By An Isolated Oceanic Disturbance., Xinyu He Jan 1989

Barotropic Shelf Circulation Forced By An Isolated Oceanic Disturbance., Xinyu He

LSU Historical Dissertations and Theses

A 'slowly varying' and 'isolated' oceanic disturbance may locally drive the shelf circulation. This situation is analytically studied using a linear, steady-state, barotropic model. The solution has a dipolar structure over the shelf. This is consistent with an integral theorem of zero net relative angular momentum on the f-plane with a sloping topography, derived herein. It is found that the forced circulation patterns are controlled by the alongshore scale of the disturbance, magnitude of bottom stress, and geometry of the shelf. In particular, by generating significant relative vorticity due to the ageostrophic motion, the friction strongly influences the center position, …

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The Impact Of Options Listing On The Information Content Of Annual Earnings Announcement., Tinwah Richard Lau Jan 1989

The Impact Of Options Listing On The Information Content Of Annual Earnings Announcement., Tinwah Richard Lau

LSU Historical Dissertations and Theses

The purpose of this study is to determine whether options listing induces additional information acquisition and processing and hence causes a commensurate reduction in the information content of annual earnings announcements. The U-statistic is used to measure the information content of annual earnings announcements. The dissertation tests the options listing effects on four different designs: (i) all exchange (NYSE/AMEX) firms, (ii) large exchange firms versus small exchange firms, (iii) positive unexpected earnings firms versus negative unexpected earnings firms, and (iv) all over-the-counter firms. The research found that, after options listing, the U-statistic of the exchange firms decreases significantly during the …

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Systolic Array Implementations With Reduced Compute Time., Abdulkader Omar Barbir Jan 1989

Systolic Array Implementations With Reduced Compute Time., Abdulkader Omar Barbir

LSU Historical Dissertations and Theses

The goal of the research is the establishment of a formal methodology to develop computational structures more suitable for the changing nature of real-time signal processing and control applications. A major effort is devoted to the following question: Given a systolic array designed to execute a particular algorithm, what other algorithms can be executed on the same array? One approach for answering this question is based on a general model of array operations using graph-theoretic techniques. As a result, a systematic procedure is introduced that models array operations as a function of the compute cycle. As a consequence of the …

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Electrochemical And Spectroscopic Characterization Of Bis(Ethylenedithio)Tetrathiafulvalene, Tetramethyltetraselenafulvalene And Their Perchlorate Salts., Roberto Luzon Wong Jan 1989

Electrochemical And Spectroscopic Characterization Of Bis(Ethylenedithio)Tetrathiafulvalene, Tetramethyltetraselenafulvalene And Their Perchlorate Salts., Roberto Luzon Wong

LSU Historical Dissertations and Theses

Electroanalytical methods (cyclic voltammetry (CV), rotating disk electrode (RDE) and rotating ring disk electrode (RRDE) voltammetry) have been used to characterize the oxidation products of bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF or ET) and tetramethyltetraselenafulvalene (TMTSF) in two commonly used solvents, acetonitrile (CH$\sb3$CN) and 1,1,2-trichloroethane (1,1,2-TCE). Cyclic voltammetry has revealed that the electro-oxidations of ET and TMTSF each occur initially via two one-electron steps representing the formation of the monocation radical and dication species. The electrochemical behaviors of TMTSF and ET in both solvents are summarized. UV/VIS spectroscopy was used to characterize TMTSF, ET and their perchlorate salts in solution. Solution spectra of TMTSF, …

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Non-Newtonian Fluid Flow In Eccentric Annuli And Its Application To Petroleum Engineering Problems., Mustafa Haciislamoglu Jan 1989

Non-Newtonian Fluid Flow In Eccentric Annuli And Its Application To Petroleum Engineering Problems., Mustafa Haciislamoglu

LSU Historical Dissertations and Theses

The fluid flow in the annular gap in oilwells is a complex problem. The geometry of the annulus is customarily simplified to concentric annular flow. In this study, a fluid flow model is developed allowing annulus to be eccentric: inner pipe located anywhere in the annulus. Thus, a more realistic representation of the actual geometry is obtained. An equation of motion that defines flow of non-Newtonian fluids in eccentric annuli is derived. A numerical solution of this equation is presented. The velocity profiles, the viscosity profiles, and the flow rate vs frictional pressure loss gradient relationship are calculated for varying …

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Harmonic Measurement And Reduction In Power Systems., Rutisurhata Kurniawan Hartana Jan 1989

Harmonic Measurement And Reduction In Power Systems., Rutisurhata Kurniawan Hartana

LSU Historical Dissertations and Theses

Harmonic voltages and currents are created by nonlinear loads in power systems. These harmonics can cause serious problems to the energy suppliers (utility companies) and energy users (consumers). This dissertation presents new techniques for harmonic measurement and the accompanying problem, harmonic reduction. To reduce harmonics, the location and magnitude of harmonic sources must be known a priori. However, to measure and monitor harmonic sources requires specialized instrumentation that is not generally permanently installed at most buses. In this study, a method is developed to use neural networks in conjunction with state estimation for monitoring and estimating harmonic sources with only …

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Theoretical And Numerical Models For Heat And Mass Transport And Groundwater Flow Near Salt Domes., David Griffin Evans Jan 1989

Theoretical And Numerical Models For Heat And Mass Transport And Groundwater Flow Near Salt Domes., David Griffin Evans

LSU Historical Dissertations and Theses

Groundwater near salt domes is an inherently complex hydrogeologic system because groundwater is subject to large lateral gradients in salinity and temperature. Moreover, groundwater flow is indirectly coupled to salt tectonics because diapirism alters the salinity and thermal conditions as a sedimentary basin evolves. In order to study this complex environment, mathematical and numerical models are developed which explicitly couple heat and dissolved salt transport to groundwater flow, and account for basin subsidence and salt diapirism. The groundwater flow field is described using a mass stream function which does not require the Boussinseq assumption. The numerical model uses a control …

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Visual Arts Teacher Education: A Study Of Current Practices In Louisiana Universities., Eloise Mcclendon Murchison Jan 1989

Visual Arts Teacher Education: A Study Of Current Practices In Louisiana Universities., Eloise Mcclendon Murchison

LSU Historical Dissertations and Theses

In this study, the researcher investigated visual arts teacher preparation programs at universities in Louisiana with particular emphasis on the curriculum component. The research was designed to survey teacher training programs and to compare the findings with delineated National Art Education Association standards. This study included only public institutions of higher education in Louisiana with visual arts education teacher preparation programs. The researcher conducted interviews at each of the 13 universities. Two of the universities worked together in a joint art education program. An interview guide was prepared and used to facilitate the interviewing process. Records and documents were also …

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Model-Based Three-Dimensional Object Recognition And Localization Using Properties Of Surface Curvatures., Wu Wang Jan 1989

Model-Based Three-Dimensional Object Recognition And Localization Using Properties Of Surface Curvatures., Wu Wang

LSU Historical Dissertations and Theses

The ability to recognize three-dimensional (3-D) objects accurately from range images is a fundamental goal of vision in robotics. This facility is important in automated manufacturing environments in industry. In contrast to the extensive work done in computer-aided design and manufacturing (CAD/CAM), the robotic process is primitive and ad hoc. This thesis defines and investigates a fundamental problem in robot vision systems: recognizing and localizing multiple free-form 3-D objects in range images. An effective and efficient approach is developed and implemented as a system Free-form Object Recognition and Localization (FORL). The technique used for surface characterization is surface curvatures derived …

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Analytical Studies Of Wireline Formation Testing And Pressure Losses Across Gravel Packs., Turhan Yildiz Jan 1989

Analytical Studies Of Wireline Formation Testing And Pressure Losses Across Gravel Packs., Turhan Yildiz

LSU Historical Dissertations and Theses

A three-dimensional (3-D) analytical model was developed to improve the analyses of the transient pressure response of a reservoir to wireline formation testing (WFT). Available analysis techniques of the WFT oversimplify the flow geometry by assuming either a radial or a spherical flow pattern. The proposed model simulates the exact flow geometry of the WFT flow pattern. The model was derived by solving the 3-D diffusivity equation coupled with the boundary conditions prevailing during the test. The Laplace transformation and the separation of variables were used to obtain the solution. The solution is expressed in terms of the infinite Fourier-Bessel …

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Simultaneous Diagonalization Of Matrices Parametrized By A Projective Algebraic Curve, William A. Adkins Jan 1989

Simultaneous Diagonalization Of Matrices Parametrized By A Projective Algebraic Curve, William A. Adkins

Faculty Publications

If K is an algebraic function field in one variable over an algebraically closed field k, then conditions are presented to insure that a matrix A ∈ M (K) is diagonalizable by means of a similarity transformation T ∈ GL(n, k). This result generalizes results of Friedland [1] and Motzkin-Taussky [4]. © 1989. n

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A Note On Negami's Polynomial Invariants For Graphs, James G. Oxley Jan 1989

A Note On Negami's Polynomial Invariants For Graphs, James G. Oxley

Faculty Publications

Negami has introduced two polynomials for graphs and proved a number of properties of them. In this note, it is shown that these polynomials are intimately related to the well-known Tutte polynomial. This fact is used, together with a result of Brylawski, to answer a question of Negami. © 1989.

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The Regular Matroids With No 5-Wheel Minor, James G. Oxley Jan 1989

The Regular Matroids With No 5-Wheel Minor, James G. Oxley

Faculty Publications

For r in {3, 4}, the class of binary matroids with no minor isomorphic to M(Wr), the rank-r wheel, has an easily described structure. This paper determines all graphs with no W5-minor and uses this to show that the class of regular matroids with no M(W5)-minor also has a relatively simple structure. © 1989.

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Regularization, Pseudofunction, And Hadamard Finite Part, R. Estrada, R. P. Kanwal Jan 1989

Regularization, Pseudofunction, And Hadamard Finite Part, R. Estrada, R. P. Kanwal

Faculty Publications

First, we discuss and correlate the various types of regularizations available in the literature for the singular function H(x) xk, where k is an integer and H(x) is the Heaviside function. Then we present the corresponding regularization for the function r-k, where r is the radial distance in Rn. Thereafter, we express the recently discovered distributional derivatives of this function in terms of pseudofunctional language commonly used in the Coulomb, gravitational, and interparticle potentials where the function 1 r plays a fundamental role. © 1989.

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On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell Jan 1989

On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell

Faculty Publications

No abstract provided.

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Constitutive Equations For Large Deformation, Rate-Dependent Plasticity For Metal Alloys., Louay Nadhim Mohammad Jan 1989

Constitutive Equations For Large Deformation, Rate-Dependent Plasticity For Metal Alloys., Louay Nadhim Mohammad

LSU Historical Dissertations and Theses

A system of constitutive equations is proposed that describes the viscoplastic behavior of a class of metal alloys when subjected to large deformations. The model is purely elastic before the plastic state is reached, and becomes elastic/viscoplastic after the plastic state has been exceeded. Three main assumptions are made with regard to the strain-rate dependency in the proposed formulation. The inelastic strain rate tensor is assumed to be normal to each point of the rate dependent convex yield surface. The initial yield stress obtained from uniaxial tests is assumed to be dependent on the rate of strain loading. Finally, the …

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