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Random Centroid Optimization Of Lutein-Enriched Oil In Water Emulsion At Acidic Ph, Armen Khachatryan Jan 2003

Random Centroid Optimization Of Lutein-Enriched Oil In Water Emulsion At Acidic Ph, Armen Khachatryan

LSU Master's Theses

Age-related macular degeneration (AMD) is a physiological condition that affects the elderly, diabetic patients, and leads to loss of vision. There are no effective therapies for AMD. The role of nutrition in preventing AMD is receiving strong scientific scrutiny. Lutein and zeaxanthin have been identified as dietary strategies that can delay the onset of AMD. Consumption of at least six milligrams of lutein per day has been reported to delay the onset of AMD by as much as 43%. However, most available food sources contain such low levels of lutein that it would be difficult to meet the daily requirement. …

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Role Of Eintermediaries In The United States Paper Supply Chain, Sanna Maria Kallioranta Jan 2003

Role Of Eintermediaries In The United States Paper Supply Chain, Sanna Maria Kallioranta

LSU Master's Theses

In an attempt to streamline the paper supply chain, paper industry vertical business-to-business eMarketplaces were established to help industry players to decrease inefficiencies in their supply chains, to minimize negative effects of economic cyclicality, and to achieve better visibility. eMarketplaces rode the hype of revolutionizing the way in which industries conduct business, citing the cost savings achieved by expanded market reach, operational efficiencies, aggregated purchasing, and finding the least expensive suppliers. Adoption of eIntermediaries has been lower than expected in the paper industry and many of the paper vertical start-ups failed when the economy softened and the dot.com bubble burst. …

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An Experimental Investigation Of Whirl Instability Including Effects Of Lubricant Temperature In Plain Circular Journal Bearings, Darryl, Jr. Chauvin Jan 2003

An Experimental Investigation Of Whirl Instability Including Effects Of Lubricant Temperature In Plain Circular Journal Bearings, Darryl, Jr. Chauvin

LSU Master's Theses

The purpose of this thesis is to experimentally investigate the effect of lubricant temperature on the presence of whirl instability in journal bearings. The first set of conditions that are studied is an extremely low eccentricity rotor and the occurrence of oil whirl at the start-up of the experiment. Lubricant temperature, bearing temperature, frequency and amplitude of vibration, and rotational speed are monitored and analyzed in relation to presence of whirl instability. Additionally, another rotor with a slightly higher eccentricity is tested with respect to the presence of such instability. Particularly with this rotor, the system is brought just below …

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Computer Assisted Screening Of Digital Mammogram Images, John Terry Sample Jan 2003

Computer Assisted Screening Of Digital Mammogram Images, John Terry Sample

LSU Doctoral Dissertations

The use of computer systems to assist clinicians in digital mammography image screening has advantages over traditional methods. Computer algorithms can enhance the appearance of the images and highlight suspicious areas. Screening provides a more thorough examination of the images. Any computer system that does screening of digital mammograms contains components to address multiple tasks such as: image segmentation, mass lesion detection and classification, and microcalcification detection and classification. This dissertation provides both effective and efficient improvements to existing algorithms, which segment mammogram images and locate mass lesions. In addition, we provide a new algorithm to evaluate and report the …

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Equations Of Parametric Surfaces With Base Points Via Syzygies, Haohao Wang Jan 2003

Equations Of Parametric Surfaces With Base Points Via Syzygies, Haohao Wang

LSU Doctoral Dissertations

Suppose $S$ is a parametrized surface in complex projective 3-space $mathbf{P}^3$ given as the image of $phi: mathbf{P}^1 imes mathbf{P}^1 o mathbf{P}^3$. The implicitization problem is to compute an implicit equation $F=0$ of $S$ using the parametrization $phi$. An algorithm using syzygies exists for computing $F$ if $phi$ has no base points, i.e. $phi$ is everywhere defined. This work is an extension of this algorithm to the case of a surface with multiple base points of total multiplicity k. We accomplish this in three chapters. In Chapter 2, we develop the concept and properties of Castelnuovo-Mumford regularity in biprojective spaces. …

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Toward A Sustainable Energy Future?: A Comparison Between U.S. And European Energy Sectors, Annett Moehner Jan 2003

Toward A Sustainable Energy Future?: A Comparison Between U.S. And European Energy Sectors, Annett Moehner

LSU Master's Theses

Since 1987, the concept of sustainable development, which tries to combine economic, social and environmental concerns into one benign development model, has become increasingly popular worldwide. To explore and explain the differences in accomplishing sustainable development, this thesis looks at one specific aspect: the energy sectors in the United States and the European Union. After giving an overview on the political and theoretical aspects of sustainable development, the various sustainability dimensions in the energy sector are explored. The following four reasons which warrant the change of the current fossil fuel intense energy sector are discussed: first, air pollution; second, insecurity …

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Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani Jan 2003

Application Of Mechanistic Models In Predicting Flow Behavior In Deviated Wells Under Ubd Conditions, Faisal Abdullah Aladwani

LSU Master's Theses

Underbalanced drilling (UBD) has increased in recent years because of the many advantages associated with it. These include increase in the rate of penetration and reduction of lost circulation and formation damage. Drilling of deviated and horizontal wells also increased since recovery can be improved from a horizontal or a deviated well. The drilling of deviated wells using UBD method will reduce several drilling related problems such as hole cleaning and formation damage. Prediction of flow and pressure profiles while drilling underbalanced in such wells will help in designing and planning of the well. The main aim of this research …

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Iddq Testing Of A Cmos 10-Bit Charge Scaling Digital-To-Analog Converter, Srinivas Rao Aluri Jan 2003

Iddq Testing Of A Cmos 10-Bit Charge Scaling Digital-To-Analog Converter, Srinivas Rao Aluri

LSU Master's Theses

This work presents an effective built-in current sensor (BICS), which has a very small impact on the performance of the circuit under test (CUT). The proposed BICS works in two-modes the normal mode and the test mode. In the normal mode the BICS is isolated from the CUT due to which there is no performance degradation of the CUT. In the testing mode, our BICS detects the abnormal current caused by permanent manufacturing defects. Further more our BICS can also distinguish the type of defect induced (Gate-source short, source-drain short and drain-gate short). Our BICS requires neither an external voltage …

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Synthesis, Characterization, And Application Of Water-Soluble Chiral Calix[4]Arene Derivatives In Spectroscopy And Capillary Electrokinetic Chromatography, Kim Hamilton Jan 2003

Synthesis, Characterization, And Application Of Water-Soluble Chiral Calix[4]Arene Derivatives In Spectroscopy And Capillary Electrokinetic Chromatography, Kim Hamilton

LSU Doctoral Dissertations

This dissertation is an account of the synthesis, characterization, and application of novel water-soluble chiral calixarenes in spectroscopy and capillary electrophoresis. It is divided into four sections. The first part describes the synthesis and nuclear magnetic resonance (NMR) characterization of four p-t-butylcalix[4]arenes bearing L-amino acid moieties on their lower rims (CX4-AA). The structure and conformation of the derivatives have been determined using one- and two-dimensional NMR techniques. Proton and carbon-13 spectra show that the derivatives are tetra-substituted and adopt a cone conformation. The preparation and characterization of silica-bonded calixarene stationary phases for capillary electrochromatography is also reported in Chapter 2. …

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Angle-Resolved Photoemission Study And Neutron Diffraction Measurements On Lasb2, Alice Acatrinei Jan 2003

Angle-Resolved Photoemission Study And Neutron Diffraction Measurements On Lasb2, Alice Acatrinei

LSU Doctoral Dissertations

LaSb2 has recently been found to have unusual magnetoresistive properties despite the fact that neither La nor Sb are magnetic. The resistance is anisotropic, and at high magnetic fields presents an anomaly that might be a result of a charge density transition. The magnetoresistance is anisotropic and linear, and the resistivity presents high relative changes when a magnetic field is applied. Discovered in 1954, LaSb2, as the rest of the light rare-earth diantimonides, was poorly studied. The anisotropic magnetic properties reported in 1998 by Bud'ko, Canfield and their collaborators make the series very interesting. A description of …

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Gender Differences In Participation Of Physical Activities: A Comprehensive Model Approach, Kay Gordon Daigle Jan 2003

Gender Differences In Participation Of Physical Activities: A Comprehensive Model Approach, Kay Gordon Daigle

LSU Doctoral Dissertations

The purpose of this study was to examine the interrelationships among gender, perceptions of peer, parent, and teacher support, perceived value and meaningfulness, perceived competence, and the intention to be physically active within a proposed model. Female and male students (N=801) enrolled in a traditional multi-activity physical education class responded to a 52-item questionnaire addressing the constructs in the model. Structural equation modeling, using LISREL, was used to identify the relationships among the constructs. Gender differences emerged in this model through direct paths as well as indirect paths among these variables. Girls were more influenced than boys by their perceptions …

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Design, Synthesis, And Applications Of Bio-Derived Crosslinking Monomers For Molecular Imprinting, Martha Sibrian-Vazquez Jan 2003

Design, Synthesis, And Applications Of Bio-Derived Crosslinking Monomers For Molecular Imprinting, Martha Sibrian-Vazquez

LSU Doctoral Dissertations

Most of the research in the field of molecular imprinting has been focused on the development of new functional monomers, in order to improve the molecular recognition properties afforded by these materials. The role of the crosslinking monomer has often been overlooked, since it is considered an inert component that only provides a scaffold to support the binding sites. However, the crosslinking monomer represents a high percent (80-90%) of the composition of molecularly imprinted polymers (MIPs), which can have a large influence on the MIPs properties. This research addresses the design, synthesis, and applications of new crosslinking monomers for molecular …

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Machine Learning Techniques For Efficient Query Processing In Kowledge Base Systems, Kevin Paul Grant Jan 2003

Machine Learning Techniques For Efficient Query Processing In Kowledge Base Systems, Kevin Paul Grant

LSU Doctoral Dissertations

In this dissertation we propose a new technique for efficient query processing in knowledge base systems. Query processing in knowledge base systems poses strong computational challenges because of the presence of combinatorial explosion. This arises because at any point during query processing there may be too many subqueries available for further exploration. Overcoming this difficulty requires effective mechanisms for choosing from among these subqueries good subqueries for further processing. Inspired by existing works on stochastic logic programs, compositional modeling and probabilistic heuristic estimates we create a new, nondeterministic method to accomplish the task of subquery selection for query processing. Specifically, …

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Black Willow (Salix Nigra) Use In Phytoremediation Techniques To Remove The Herbicide Bentazon From Shallow Groundwater, Robert Mark Conger Jan 2003

Black Willow (Salix Nigra) Use In Phytoremediation Techniques To Remove The Herbicide Bentazon From Shallow Groundwater, Robert Mark Conger

LSU Doctoral Dissertations

Wetland environments have been impacted by the activities of man over the past several hundred years in North America. Industrialization into wetland areas has brought with it anthropogenic compounds that have been released into soils and groundwater. The use of phytoremediation to detoxify soil and groundwater began in the mid 1990's and has become a popular remediation technology. In 1994, a feasibility study for using phytoremediation in such an industrialized wetland area was conducted at a petrochemical facility at BASF Corporation, located about 20 kilometers south of Baton Rouge, Louisiana in Ascension Parish. The test site consisted of low level …

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Optimization Of The Light Dynamics In The Hydraulically Integrated Serial Turbidostat Algal Reactor (Histar), Barbara Christine Benson Jan 2003

Optimization Of The Light Dynamics In The Hydraulically Integrated Serial Turbidostat Algal Reactor (Histar), Barbara Christine Benson

LSU Doctoral Dissertations

The research objective was the optimization of light dynamics in a Hydraulically Integrated Serial Turbidostat Algal Reactor (HISTAR). A deterministic model of HISTAR productivity that was responsive to manipulations of photosynthetic photon flux fluence rate (PPFFR) was developed, calibrated, and applied. A series of experiments was conducted to define the mathematical equations that best describe three relationships. The first relationship was between the elevation (E) of the light source and the culture surface PPFFR (Io). The second relationship was between the biomass concentration (X) in the experimental unit and the average PPFFR in the reactor (Ia). …

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Collective Efficacy: A Framework For Understanding Classroom Teacher's Perceptions Of Integrating Physical Activity, Melissa Ann Park Jan 2003

Collective Efficacy: A Framework For Understanding Classroom Teacher's Perceptions Of Integrating Physical Activity, Melissa Ann Park

LSU Doctoral Dissertations

Children’s physical inactivity is becoming an important health concern, and it has been suggested by professionals that school programs can be important in the effort to increase activity levels. Physical education specialists cannot achieve the goal of significantly increasing children’s activity in isolation, and it is apparent that whole school programs at the elementary level have the potential to foster active lifestyles. If those programs are to be successful, all school personnel must play a role, so it is important to find ways to facilitate their involvement. The purpose of this study was to use collective efficacy as a framework …

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Splitter Theorems For 3- And 4-Regular Graphs, Jinko Kanno Jan 2003

Splitter Theorems For 3- And 4-Regular Graphs, Jinko Kanno

LSU Doctoral Dissertations

Let g be a class of graphs and ≤ be a graph containment relation. A splitter theorem for g under ≤ is a result that claims the existence of a set O of graph operations such that if G and H are in g and H≤G with G≠H, then there is a decreasing sequence of graphs from G to H, say G=G0≥G1≥G2...Gt=H, all intermediate graphs are in g, and each Gi can be obtained from Gi-1 by applying a single …

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Solid-Phase Dna Sequencing Reactions Performed In Micro-Capillary Reactors And Solid-Phase Reversible Immobilization In Microfluidic Chips For Purification Of Dye-Labeled Dna Sequencing Fragments, Yichuan Xu Jan 2003

Solid-Phase Dna Sequencing Reactions Performed In Micro-Capillary Reactors And Solid-Phase Reversible Immobilization In Microfluidic Chips For Purification Of Dye-Labeled Dna Sequencing Fragments, Yichuan Xu

LSU Doctoral Dissertations

The research presented in this dissertation involves micro-capillary reactors for solid phase DNA sequencing, the identification of dye terminator sequencing fragments with time-resolved methods, and purification of dye-labeled DNA fragments using solid- phase reversible immobilization in microfluidic chips. Solid-phase micro-reactors have been prepared for DNA sequencing applications using slab gel electrophoresis. A PCR product was immobilized to the interior wall of a fused-silica capillary tube via a biotin-streptavidin linkage. Solid-phase sequencing was carried out in micro-capillary reactors using a four-lane, single color dye primer chemistry strategy. The read length was found to be 589 bases. The complementary DNA fragments generated …

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Clay Landfill Liners Subject To Variable Interfacial Redox And Ph Conditions-Heavy Metal And Clay Interactions, Ping Zhou Jan 2003

Clay Landfill Liners Subject To Variable Interfacial Redox And Ph Conditions-Heavy Metal And Clay Interactions, Ping Zhou

LSU Doctoral Dissertations

Municipal landfill leachate contains high levels of metal species, including Cu, Zn, Cd and Pb generating competitive interactions between these metal species and the landfill clay liner materials. Characterization of the clay fraction, physical and chemical characteristics of landfill clay liner materials, the competitive interaction of metal species with clay liner materials, the kinetic modeling of metal species transport in clay liner, and the effect of cyclic interfacial redox potential on the structural changes to the clay liner and leachate metal transport were investigated in this study. The clay liner materials studied included Na-bentonite, kaolinite and Amite soil (sandy silty …

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Book Embeddings Of Graphs, Robin Leigh Blankenship Jan 2003

Book Embeddings Of Graphs, Robin Leigh Blankenship

LSU Doctoral Dissertations

We use a structural theorem of Robertson and Seymour to show that for every minor-closed class of graphs, other than the class of all graphs, there is a number k such that every member of the class can be embedded in a book with k pages. Book embeddings of graphs with relation to surfaces, vertex extensions, clique-sums and r-rings are combined into a single book embedding of a graph in the minor-closed class. The effects of subdividing a complete graph and a complete bipartite graph with respect to book thickness are studied. We prove that if n ≥ 3, …

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Perceptions Of Stereotypes In Hispanic Children's Literature, Nancy Gomez Jan 2003

Perceptions Of Stereotypes In Hispanic Children's Literature, Nancy Gomez

LSU Doctoral Dissertations

This study attempted to determine the accurateness of the representation of the Hispanic culture in children’s books. I interviewed ten people: five non-Hispanic and five Hispanic, and I found that the Hispanic people do not seem to pay as much attention to physical features as non-Hispanic people do. However, they were concerned about the portrayal of the Hispanic culture in traditional ways: the traditional roles of women, the traditional dress, the architecture of the houses and the portrayal of the Hispanic people living in rural areas and being extremely poor. It appears that from the timeline covered by the books, …

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Control Of Transport Dynamics In Overlay Networks, Qishi Wu Jan 2003

Control Of Transport Dynamics In Overlay Networks, Qishi Wu

LSU Doctoral Dissertations

Transport control is an important factor in the performance of Internet protocols, particularly in the next generation network applications involving computational steering, interactive visualization, instrument control, and transfer of large data sets. The widely deployed Transport Control Protocol is inadequate for these tasks due to its performance drawbacks. The purpose of this dissertation is to conduct a rigorous analytical study on the design and performance of transport protocols, and systematically develop a new class of protocols to overcome the limitations of current methods. Various sources of randomness exist in network performance measurements due to the stochastic nature of network traffic. …

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Solute Transport In A Porous Medium: A Mass-Conserving Solution For The Convection-Dispersion Equation In A Finite Domain, William Golz Jan 2003

Solute Transport In A Porous Medium: A Mass-Conserving Solution For The Convection-Dispersion Equation In A Finite Domain, William Golz

LSU Doctoral Dissertations

This dissertation considers the proper mathematical description for the physical problem of a miscible solute undergoing longitudinal convective-dispersive transport with constant production, first-order decay, and equilibrium sorption in a porous medium. Initial and input concentrations may be any continuously differentiable functions and the mathematical system is articulated for a finite domain. This domain yields a mass balance which requires Robin (i.e., third-type) boundaries, which describe a continuous flux but a discontinuous resident-concentration. The discontinuity in the resident concentration at the outflow boundary yields an underdetermined system when the exit concentration is not experimentally measured. This is resolved by defining the …

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Fractal Compression And Analysis On Remotely Sensed Imagery, Ke Xiao Jan 2003

Fractal Compression And Analysis On Remotely Sensed Imagery, Ke Xiao

LSU Doctoral Dissertations

Remote sensing images contain huge amount of geographical information and reflect the complexity of geographical features and spatial structures. As the means of observing and describing geographical phenomena, the rapid development of remote sensing has provided an enormous amount of geographical information. The massive information is very useful in a variety of applications but the sheer bulk of this information has increased beyond what can be analyzed and used efficiently and effectively. This uneven increase in the technologies of gathering and analyzing information has created difficulties in its storage, transfer, and processing. Fractal geometry provides a means of describing and …

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The Impact Of Whole-Plant Instruction Preservice Elementary Teachers' Understanding Of Plant Science Principles, Christine Collins Hypolite Jan 2003

The Impact Of Whole-Plant Instruction Preservice Elementary Teachers' Understanding Of Plant Science Principles, Christine Collins Hypolite

LSU Doctoral Dissertations

The purpose of this research was to determine how an inquiry-based, whole-plant instructional strategy would affect preservice elementary teachers’ understanding of plant science principles. This study probed: what preservice teachers know about plant biology concepts before and after instruction, their views of the interrelatedness of plant parts and the environment, how growing a plant affects preservice teachers’ understanding, and which types of activity-rich plant themes studies, if any, affect preservice elementary teachers’ understandings. The participants in the study were enrolled in two elementary science methods class sections at a state university. Each group was administered a preinstructional test at the …

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The Effect On Water Quality Of Riverine Input Into Coastal Wetlands, Robert Raymond Lane Jan 2003

The Effect On Water Quality Of Riverine Input Into Coastal Wetlands, Robert Raymond Lane

LSU Doctoral Dissertations

This dissertation focuses on impact on water quality of two freshwater diversions, the Bonnet Carre Spillway and the Caernarvon freshwater diversion, as well as the Atchafalaya River Estuarine Complex. As water passed through the Bonnet Carre Spillway, there were reductions in total suspended sediment concentrations of 82-83%, in nitrite+nitrate of 28-42%, in total nitrogen (TN) of 26-30%, and in total phosphorus (TP) of 50-59%. The Si:N ratio generally increased and the N:P ratio decreased from the river to the plume edge in Lake Pontchartrain. At the Caernarvon diversion, there were reductions in concentrations of dissolved inorganic Si, N, and P …

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Analyzing The Impact Of Changing Software Requirements: A Traceability-Based Methodology, James Steven O'Neal Jan 2003

Analyzing The Impact Of Changing Software Requirements: A Traceability-Based Methodology, James Steven O'Neal

LSU Doctoral Dissertations

Software undergoes change at all stages of the software development process. Changing requirements represent risks to the success and completion of a project. It is critical for project management to determine the impact of requirement changes in order to control the change process. We present a requirements traceability based impact analysis methodology to predictively evaluate requirement changes for software development projects. Trace-based Impact Analysis Methodology (TIAM) is a methodology utilizing the trace information, along with attributes of the work products and traces, to define a requirement change impact metric for determining the severity of a requirement change. We define the …

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Level Of Essentialness Of A Node In Flowcharts And Its Application To Program Testing, Osman Kandara Jan 2003

Level Of Essentialness Of A Node In Flowcharts And Its Application To Program Testing, Osman Kandara

LSU Doctoral Dissertations

Program testing is important to develop bug free software. A common form of program testing involves selecting test cases which execute (cover) a given set W of statements in the program. In regression testing, W typically forms a small subset of the program. It is often possible to find an alternate small set W so that execution of W' implies execution of W. We develop concepts and algorithms for finding W' as small as possible with the condition that the statements in W' are "close" to those in W in terms of program structure. These concepts generalize the notion of …

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The Impact Of A Life-Application Learning Instructional Program On Struggling Readers At The Middle School Level, Angelle Rae Stringer Jan 2003

The Impact Of A Life-Application Learning Instructional Program On Struggling Readers At The Middle School Level, Angelle Rae Stringer

LSU Doctoral Dissertations

This eight-week descriptive study examined the impact of the incorporation of a Life-Application Learning Methods Program on struggling middle school readers. Two questions were explored: 1) How did incorporating life–application learning into the middle school curriculum impact reading motivation?, and 2) How did incorporating life-application learning in the middle school curriculum impact the reading levels? Participants in the study were eight eighth-grade students considered to be struggling readers Qualitative methods were used for this study utilizing responses from a survey, two inventories, student journals, and researcher observations. Data gathered suggested that students are more likely to become motivated and engaged …

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Gravitational Radiation Detectability Of Supernova 1987a'S Remnant Fully Matched Filter For Double Resonant Gravitational Detector, Giovanni Santostasi Jan 2003

Gravitational Radiation Detectability Of Supernova 1987a'S Remnant Fully Matched Filter For Double Resonant Gravitational Detector, Giovanni Santostasi

LSU Doctoral Dissertations

Part I There is some observational evidence of the presence of a pulsating light source in the remnant of the supernova (SN) 1987A [1]. This source is considered to be a rotating neutron star. Fourier analysis of the light intensity of this source reveals a main narrow frequency peak and side bands that are understood as a modulation of the main sinusoidal signal. A particular model of the neutron star invokes a precessing object to explain the modulation. From the Fourier spectrum of the source and changes in the frequency value, we can determine important parameters of the spinning neutron …

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