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Articles 2311 - 2324 of 2324
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Reconceiving Curriculum: An Historical Approach, Stephen Shepard Triche
Reconceiving Curriculum: An Historical Approach, Stephen Shepard Triche
LSU Doctoral Dissertations
This dissertation reconceives curriculum through an historical approach that employs Ludwig Wittgenstein’s later philosophy. Curriculum is more than the knowledge taught in school. Curriculum, as I a theorist conceives it, is concerned with the broader intellectual and ideological ways a society thinks about education. Hence, the current school curriculum’s focus on specific learning outcomes offers a limited view of the knowledge fashioned by a society, thereby offering an intellectual and social history that is highly selective. Wittgenstein’s concept of “language-games” offers curricularists a way to re-include some of these stories. The concept of curriculum emerges at the end of the …
Service Learning: A Study Of Administrators' Goals At A Research I University, Christy Sanders
Service Learning: A Study Of Administrators' Goals At A Research I University, Christy Sanders
LSU Doctoral Dissertations
This case study explored the administrators' goals of a service learning program at a Research I university. This research was aimed at discovering administrators' goals and determining whether or not these goals were achieved, as perceived by students, administrators, community service agency directors, and faculty members. A structured, tape-recorded interview was used to gather data from participants in all groups. Barriers to implementation of service learning by faculty, students, and administrators included time constraints, lack of institutional support and lack of clarity as to what constituted service learning. University engagement in service learning was defined as the process by which …
Electronic And Structural Properties Of Rare Gas Cation Clusters, Jose Alejandro Gascon
Electronic And Structural Properties Of Rare Gas Cation Clusters, Jose Alejandro Gascon
LSU Doctoral Dissertations
We study structure and ground and excited state properties of rare gas cation clusters, Rg+N, for N=3-60. The main goal is to understand how the positive charge is delocalized over the cluster and the relationship between cluster geometry and delocalization. He+N, Ar+N, and Xe+N are selected as representatives of the rare gas elements. We perform Monte Carlo simulations to obtain finite temperature properties of the energy spectrum. The Hamiltonian of the system is based on a semi-empirical model whose parameters are obtained through the fitting of experimental and calculated …
Markov Models To Estimate And Describe Survival Time And Experience In Cohorts With High Euthanasia Frequency, Giselle Louise Hosgood
Markov Models To Estimate And Describe Survival Time And Experience In Cohorts With High Euthanasia Frequency, Giselle Louise Hosgood
LSU Doctoral Dissertations
Unique to survival analysis of veterinary clinical data is classification of observations from euthanized animals. The first study highlighted limitations of Kaplan-Meier product limit analysis (KM) of veterinary clinical data. Three data sets with different outcome proportions (alive, lost-to-follow-up, dead due to disease, dead due to other, euthanized due to disease, euthanized due to other) were used. Different classifications of observations from euthanized animals caused inconsistent conclusions of significant differences between strata within data sets. At times, ranking of median survival time estimates for strata was reversed. The KM was found inappropriate to evaluate observations from euthanized animals. This finding, …
Hydrodynamics And Freshwater Diversion Within Barataria Basin, Dongho Park
Hydrodynamics And Freshwater Diversion Within Barataria Basin, Dongho Park
LSU Doctoral Dissertations
In order to understand the physical processes in the Barataria estuary, a previously developed two-dimensional, depth-integrated hydrodynamic model is applied to simulate estuarine processes. The equations for conservation of mass and momentum predict specific physical processes when forced by tidal and salinity variations at the open boundaries, wind forcing patterns, precipitation and evaporation over the model domain, and freshwater runoff as point sources. This study is focused on examining the impact of freshwater dispersion from the freshwater sources. Thus, a hydrologic model was developed to estimate runoff. Furthermore grid size was reduced, a new advective code added, and baroclinic effects …
On Properties Of Linear Control Systems On Lie Groups, Fabiana Cardetti
On Properties Of Linear Control Systems On Lie Groups, Fabiana Cardetti
LSU Doctoral Dissertations
In this work we study controllability properties of linear control systems on Lie groups as introduced by Ayala and Tirao in [AT99]. A linear control system _x0006_Σ Lie group G is defined by x' = X(x) + Σkj=1 ujYj(x), where the drift vector field X is an infinitesimal automorphism, uj are piecewise constant functions, and the control vectors Yj are left-invariant vector fields. Properties for the flow of the infinitesimal automorphism X and for the reachable set defined by _x0006_Σ are presented in Chapter 3. Under a condition similar to the Kalman …
Barium And Lithium In Foraminifera: Glacial-Interglacial Changes In The North Atlantic, Jenney M. Hall
Barium And Lithium In Foraminifera: Glacial-Interglacial Changes In The North Atlantic, Jenney M. Hall
LSU Doctoral Dissertations
The trace element content of calcareous foraminifera provides a powerful tool to the study of glacial-interglacial changes in the physical and chemical properties of the ocean. Foraminifera incorporate barium in direct proportion to its concentration in seawater. Using barium as a nutrient proxy, Ba/Ca in benthic Planulina wuellerstorfi is used to reconstruct changes in thermocline ventilation and mid-depth circulation in the North Atlantic during the last glacial and deglacial time. Rivers are concentrated in barium compared to surface seawater. Therefore, barium in planktonic Neogloboquadrina pachyderma is used to identify deglacial meltwater in the Arctic Ocean. Foraminiferal Li/Ca was analyzed to …
On The Stabilization And Regularization Of Rational Approximation Schemes For Semigroups, Simone Flory
On The Stabilization And Regularization Of Rational Approximation Schemes For Semigroups, Simone Flory
LSU Doctoral Dissertations
In this work we discuss consistency, stability and convergence of rational approximation methods for strongly continuous semigroups on Banach spaces. The Lax-Chernoff theorem shows that in this setting consistency and stability assumptions are necessary to obtain strong uniform convergence of approximation methods. We investigate rational approximation methods for strongly continuous semigroups and their consistency properties, with special emphasis on A-stable methods and Padé-type approximations. In particular, we discuss the stability and convergence properties of these schemes, including the stability of the well-known and widely used Backward-Euler and Crank-Nicolson Schemes. Furthermore, we modify stabilization techniques developed by Hansbo, Larsson, Luskin, Rannacher, …
Analysis Of Inorganic Materials Using Advanced Nmr And Nqr Techniques, Anthony Adrian Mrse
Analysis Of Inorganic Materials Using Advanced Nmr And Nqr Techniques, Anthony Adrian Mrse
LSU Doctoral Dissertations
Several advanced solid-state nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) techniques have been applied to inorganic materials of commercial interest. The specific techniques applied to each system were chosen to solve specific obstacles which impeded the flow of industrial science.
First, the dispersion of brominated flame retardants in polymers is monitored using pulsed 81Br NQR (nuclear quadrupole resonance) techniques. The NQR spectrometer consists of a homemade NMR console and an automatically tuned loop-gap resonator probe. The two factors which affect the 81Br NQR transition frequencies of brominated aromatics are: electron-donating and withdrawing substituents on the ring …
The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen
The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen
LSU Doctoral Dissertations
Polycyclic aromatic amines (arylamines) are a class of chemical carcinogens that are prevalent in environmental and industrial settings. In order to study the mechanism of their toxicity a quantitative and qualitative detection method was developed to measure the C8-adenine adducts of benzidine and 2-aminofluorene in DNA samples. To do this a novel synthetic method using a palladium catalyst was developed to prepare authentic and deuterated arylamine adducts to serve as standards. These standards were then used to develop a high performance liquid chromatography, electrospray, tandem mass spectrometry, isotope dilution, detection method. To demonstrate the validity of this method two spike …
Analysis Of Near-Infrared Dye-Labeled Sanger Sequencing Fragments With Gel Electrophoresis Using The Time-Resolved Flourescence Lifetime Indentification Methods, Suzanne Jeanel Lassiter
Analysis Of Near-Infrared Dye-Labeled Sanger Sequencing Fragments With Gel Electrophoresis Using The Time-Resolved Flourescence Lifetime Indentification Methods, Suzanne Jeanel Lassiter
LSU Doctoral Dissertations
The research presented in this dissertation involves the identification of sequencing fragments with time-resolved methods. For this application, near-infrared heavy-atom tricarbocyanine dyes were developed in our laboratory, which can be excited with a single laser and emission collected using a single detection channel. The dyes have four spectroscopically unique, but relatively short lifetimes that can be altered by the intramolecular heavy-atom they contain. The work described here involves the optimization of dye-primer chemistry for preparing Sanger sequencing reactions for longer reads and the optimization of the separation matrix for capillary gel electrophoresis that produces favorable statistical analysis of the aforementioned …
Bounding The Wild Set (Counting The Minimum Number Of Wild Primes In Hilbert Symbol Equivalent Number Fields), Marius M. Somodi
Bounding The Wild Set (Counting The Minimum Number Of Wild Primes In Hilbert Symbol Equivalent Number Fields), Marius M. Somodi
LSU Doctoral Dissertations
This dissertation makes a contribution to the study of Witt rings of quadratic forms over number fields. To every pair of algebraic number fields with isomorphic Witt rings one can associate a number, called the minimum number of wild primes. The situation is particularly nice when this number is 0; often it is not 0. Earlier investigations have established lower bounds for this number. In this dissertation an analysis is presented that expresses the minimum number of wild primes in terms of the number of wild dyadic primes. This formula not only gives immediate upper bounds, but can be considered …
Artin-Schreier Families And 2-D Cycle Codes, Cem Guneri
Artin-Schreier Families And 2-D Cycle Codes, Cem Guneri
LSU Doctoral Dissertations
We start with the study of certain Artin-Schreier families. Using coding theory techniques, we determine a necessary and sufficient condition for such families to have a nontrivial curve with the maximum possible number of rational points over the finite field in consideration. This result produces several nice corollaries, including the existence of certain maximal curves; i.e., curves meeting the Hasse-Weil bound.We then present a way to represent two-dimensional (2-D) cyclic codes as trace codes starting from a basic zero set of its dual code. This representation enables us to relate the weight of a codeword to the number of rational …
Numerical Simulations Of Dynamical Mass Transfer In Binaries, Patrick Michael Motl
Numerical Simulations Of Dynamical Mass Transfer In Binaries, Patrick Michael Motl
LSU Doctoral Dissertations
We present results from investigations of mass transfer instability in close binary star systems. By unstable mass transfer we mean the exchange of material where the response of the binary to the initial Roche lobe overflow causes the donor to loose even more material. Our work is guided by approximate arguments that dictate the stability boundaries for binary star systems. To proceed further one must explicitly treat extended mass and velocity distributions that are both nitially, and through their subsequent evolution in time, self-consistent. In this dissertation, we present the first three-dimensional, fully self-consistent treatment of mass transfer in close …