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Hierarchical State Estimation For Wide Area Power Systems, Srivatsan Lakshminarasimhan Dec 2006

Hierarchical State Estimation For Wide Area Power Systems, Srivatsan Lakshminarasimhan

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This thesis presents the application of hierarchical state estimation techniques to consolidate the state output of a wide area power system network. In a wide area network a large number of interconnections exist between various utilities of the wide area. Power transactions between areas occur over large distances and hence for better security there is a need to monitor the state of the entire wide area systems. Hierarchical state estimation is preferred over integrated state estimation, due to the reduced computational time.
Using existing state estimators of the member utilities of the wide area in the bottom level of hierarchical …

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Remediation Of Risks In Natural Gas Storage Produced Waters: The Potential Use Of Constructed Wetland Treatment Systems, Brenda Johnson Dec 2006

Remediation Of Risks In Natural Gas Storage Produced Waters: The Potential Use Of Constructed Wetland Treatment Systems, Brenda Johnson

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Natural gas storage produced waters (NGSPWs) are generated in large volumes, vary in composition, and often contain constituents in concentrations and forms that are toxic to receiving system biota. This research had three major objectives: 1) Characterize NGSPWs to discern the constituents of concern present in these waters; 2) Design and measure performance of a pilot-scale hybrid constructed wetland treatments system (CWTS) for treating NGSPWs, and; 3) Discern the reliability of the Turner Designs TD500 handheld fluorometer for measurement of oil-in-water in produced waters containing algae. Produced waters contained chlorides, metals, and organics as constituents of concern. Using simulated produced …

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Haptics In Robotics And Automotive Systems, Erhun Iyasere Dec 2006

Haptics In Robotics And Automotive Systems, Erhun Iyasere

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Haptics is the science of applying touch (tactile) sensation and control to interaction with computer applications. The devices used to interact with computer applications are known as haptic interfaces. These devices sense some form of human movement, be it finger, head, hand or body movement and receive feedback from computer applications in form of felt sensations to the limbs or other parts of the human body. Examples of haptic interfaces range from force feedback joysticks/controllers in video game consoles to tele-operative surgery. This thesis deals with haptic interfaces involving hand movements. The first experiment involves using the end effector of …

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Occurrence And Control Of Large Patch (Rhizoctonia Solani Ag 2`2 «Lp«On Seashore Paspalum (Paspalum Vaginatum O. Swartz) In South Carolina, Alejandro Canegallo Dec 2006

Occurrence And Control Of Large Patch (Rhizoctonia Solani Ag 2`2 «Lp«On Seashore Paspalum (Paspalum Vaginatum O. Swartz) In South Carolina, Alejandro Canegallo

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Seashore paspalum is a new turfgrass being evaluated in the southeastern United States due to its tolerance to salinity and sodicity. Rhizoctonia solani AG 2-2 `LP` was isolated from seashore paspalum exhibiting symptoms typical of Large Patch (LP). The disease was identified based on field symptoms, lesions on the plant, and the fungus identified based on cultural characteristics, multinucleate hyphal cells, and anastomosis with a known tester isolate of R. solani AG 2-2 `LP` from zoysia grass.
Two research putting greens were constructed in 2005 located in Florence, SC and near Bluffton, SC and planted to seashore paspalum cultivars SeaIsle …

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Emission Reduction In Small Displacement Diesel Engines Using Cooled Exhaust Gas Recirculation, Chris Simoson Dec 2006

Emission Reduction In Small Displacement Diesel Engines Using Cooled Exhaust Gas Recirculation, Chris Simoson

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A reduced-order dynamic model is presented and experimentally validated to demonstrate the use of cooled exhaust gas recirculation to alleviate the tradeoff between nitric oxide reduction and performance preservation in a small displacement diesel engine. Exhaust gas recirculation (EGR) is an effective method for internal combustion engine oxides of nitrogen (NOx) reduction, but its thermal throttling diminishes power efficiency. The capacity to cool exhaust gases prior to merging with intake air may achieve the desired pollutant effect while minimizing engine performance losses.
Simulation and experimental results revealed significant NOx reductions throughout all testing scenarios using EGR, but also experienced a …

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Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu Dec 2006

Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu

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A fundamental understanding of flow and its influence on the microstructure is required to obtain carbon materials with desired properties. The objective of this research was to investigate the flow and microstructural behavior of a synthetic mesophase pitch (AR-HP) in rheometric and processing flow conditions. In addition, simulation studies were performed to establish a frame work for modeling the flow behavior of this complex material in different flow situations.
The steady-shear viscosities obtained from a cone-plate rheometer during increasing rate-sweep experiments exhibited a shear-thinning region (Region I) with a slope of about -0.2 and a plateau (Region II) region. The …

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Modeling Of The Transient Behavior Of Heat Pipes With Room-Temperature Working Fluids, Pascal Brocheny Dec 2006

Modeling Of The Transient Behavior Of Heat Pipes With Room-Temperature Working Fluids, Pascal Brocheny

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The heat pipe is a capillary-driven and two-phase flow device, capable of transporting and converting large amounts of energy with minimal losses. As a means of thermal management, uses of heat pipe technology not only include thermal control of satellites and spacecrafts in aerospace applications, but also the cooling of electronic components for ground applications. Recently, there has been a flourishing interest in exploring the use of heat pipe technology in the automotive field. However, in many thermal control applications, heat pipes using room-temperature working fluids, such as water or ammonia, with operating temperatures between 200 K (-73ºC) and 550 …

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Dielectric Properties And Method Of Characterizing Ceramic Powders And Multiphase Composites, Ravi Kiran Kota Dec 2006

Dielectric Properties And Method Of Characterizing Ceramic Powders And Multiphase Composites, Ravi Kiran Kota

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Barium Titanate was the first developed ferroelectric ceramic material and even today it is widely used. It is also a well-known material used for capacitors. The only reason behind a wide range of applications is that barium titanate boasts of high dielectric properties. A phase transition from cubic to tetragonal at normal working temperatures provides enhanced dielectric properties in this electronic material. For any application and design, the most inquired property is the dielectric constant. Predicting the dielectric constant is very much required as it is the pre-requisite. This is the major objective of the present work. To estimate the …

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Assembly And Modification Of A Hyperthermal And Low Energy Ion Beamline For Detecting Electron-Hole Pair Production In Schottky Diodes, Matthew Ray Dec 2006

Assembly And Modification Of A Hyperthermal And Low Energy Ion Beamline For Detecting Electron-Hole Pair Production In Schottky Diodes, Matthew Ray

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A hyperthermal and low energy ion beamline to measure electron-hole pair production due to ion bombardment of Schottky diodes has been modified and assembled.
A brief overview of the instrument is given and the reason for operating the ion beamline in the hyperthermal and low energy regime is discussed. The capabilities of the ion beamline are unique and provide the means to measure quantities that offer insight into various energy exchange mechanisms that occur at surfaces. Combined with the ability to accept Schottky diode samples, the beamline is capable of measuring both charge transfer and electron-hole pair production caused by …

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The Impact Of A Ninth- And Tenth-Grade Academy Program On Student Attendance, Discipline, And Achievement, Sandra Wooten Dec 2006

The Impact Of A Ninth- And Tenth-Grade Academy Program On Student Attendance, Discipline, And Achievement, Sandra Wooten

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ABSTRACT The purpose of this study was to examine the impact of an Academy Program on freshman and sophomore attendance, suspensions out of school, PLAN and PSAT scores, and the number of students retained in ninth and tenth grades. With the Academy Program at Gaffney High School, the amount of time spent in mathematics and English language arts classes was doubled, staff development was provided, instructional methods were changed, data was analyzed to modify instruction, and successes were celebrated. School data from two years before and two years after implementation were examined to determine whether any significant differences existed. Results …

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Perfluoroalkyl (Aryl) Sulfonimide Zwitterions, Hua Mei Dec 2006

Perfluoroalkyl (Aryl) Sulfonimide Zwitterions, Hua Mei

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This research focuses on superacid perfluoroalkyl(aryl) sulfonimides and their derivatives as a source of stable zwitterionic salts. The strong resonance stabilization of sulfonimides imparts unexpected stability to the zwitterions.
Two types of zwitterions were investigated. The first are symmetrical diaryliodonium zwitterions (DZs) as potential photo acid generators (PAGs) for microlithography. Driven by the demand for smaller feature sizes in the microelectronics industry, microlithography using shorter wavelength light has evolved and new PAGs are of interest. New DZs are potentially useful because they have good thermal stability and may be structurally modified to alter their spectral absorption characteristics. As an extension …

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Toxicological Effects Of Endocrine Disrupting Compounds In Bluegill, Pamela Truman Dec 2006

Toxicological Effects Of Endocrine Disrupting Compounds In Bluegill, Pamela Truman

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The water quality in the Reedy River basin has been shown to be impacted from the diverse and highly urbanized land uses within the watershed. The objective of this study was to examine the observed toxicological effects of EDCs that may be present in the Reedy River watershed by using a suite of biomarkers that were measured in indigenous fish to characterize the exposure and biological effects of these contaminants. Bluegill were analyzed for unnatural estrogenic effects such as: 1) Vitellogenin (VTG) 2) Activity of estrogenic compounds in bile extractions 3) UDP-glucuronosyltransferase (UGT) activity. This biomarker study provides a more …

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Simulation And Characterization Of Tire Nonuniformity-Induced Steering Nibble Vibrations Through Integrated Subsystems Modeling, Derek Mangun Dec 2006

Simulation And Characterization Of Tire Nonuniformity-Induced Steering Nibble Vibrations Through Integrated Subsystems Modeling, Derek Mangun

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Periodic force variations produced by nonuniform tire/wheel assemblies are known root causes of torsional steering wheel vibrations known as 'nibble'. Previous studies have sought to investigate this issue through modeling or experimentation involving the entire vehicle or specific subsystems, however a direct link between objectively measured tire force variations and the vibration levels perceived by vehicle occupants has yet to be established. Analytical models of a nonuniform tire, double-wishbone suspension system, and rack and pinion steering system are sourced from literature and integrated into a single subsystem-level model validated against experimental data obtained as part of a collaborative effort. The …

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Online Resources For Late Additions To The Solar Nebula, Allen Parker Dec 2006

Online Resources For Late Additions To The Solar Nebula, Allen Parker

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The presence of an excess of short-lived radionuclides in the early protoplanetary disk has been inferred from studying how the distribution of the abundances, in materials like Ca-Al-rich inclusions, differ from the solar abundance distribution (SAD). The likely source of these radioactivites is a supernova that ejected material into the early solar system. This thesis will discuss the solar abundance distribution and how a supernova may have contributed a 'late addition' of material into the early solar system. In addition, we have constructed online resources for studying these topics. This thesis will outline the Solar Abundance Tool, which allows a …

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Preservice Teachers' Procedural And Conceptual Understanding Of Fractions And The Effects Of Inquiry-Based Learning On This Understanding, Hope Marchionda Dec 2006

Preservice Teachers' Procedural And Conceptual Understanding Of Fractions And The Effects Of Inquiry-Based Learning On This Understanding, Hope Marchionda

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ABSTRACT Non-negative rational numbers play a major role in the K-8 curriculum and continue to permeate mathematics content through high school and college in all strands of mathematics. The difficulty that both students and teachers encounter with these concepts is well documented in the literature. This study looked at preservice teacher knowledge and how an alternative means of instruction might improve their conceptual understanding of fractions. To accomplish this task, the study took place in two stages over the course of two semesters. During the first stage, preservice teachers' conceptual and procedural knowledge of fractions and their associated algorithms were …

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The Molecular And Ecophysiological Roles Of Rubisco Activase And Rubisco Activase Likes In Photosynthetic Thermal Regulation Of Acer Rubrum And Arabidopsis Thaliana , David Weston Dec 2006

The Molecular And Ecophysiological Roles Of Rubisco Activase And Rubisco Activase Likes In Photosynthetic Thermal Regulation Of Acer Rubrum And Arabidopsis Thaliana , David Weston

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Determining the consequences of human impact on our current and future climate is proving to be to be one of the greater challenges in modern biology. Current global models employing coupled atmosphere and terrestrial carbon feedbacks range in their predictions from the inconsequential to that of vast food shortages and species extinctions. However, there is hope that the emergence of new molecular approaches will revolutionize our understanding of plant and animal responses to a changing environment, allowing for higher predictive power when scaling up from the level of the individual to ecosystem-scale processes. This dissertation is an initial attempt for …

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Characterization Of Capillary-Channeled Polymer Fibers As Stationary Phases For High-Performance Liquid Chromatography Of Macromolecules, Dwella Nelson Dec 2006

Characterization Of Capillary-Channeled Polymer Fibers As Stationary Phases For High-Performance Liquid Chromatography Of Macromolecules, Dwella Nelson

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Capillary-channeled polymer (C-CP) fibers are being developed and characterized as high-performance liquid chromatography (HPLC) stationary phases for reversed-phase separations of proteins. Conventional porous phases are not well suited for separating large macromolecules due to the slow diffusivity of the molecules, large diffusional distances, and stagnant mobile phase zones within the column. Stationary phases are continually being developed to address the challenges associated with HPLC of proteins and other macromolecules in general. C-CP fiber stationary phases are an alternative to conventional bead technology and offer a variety of chemical and physical advantages. The fibers can be selected for their chemical functionality …

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Modeling And Simulation Of Friction-Limited Continuously Variable Transmissions, Nilabh Srivastava Dec 2006

Modeling And Simulation Of Friction-Limited Continuously Variable Transmissions, Nilabh Srivastava

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Over the last few decades, a lot of research effort has increasingly been directed towards developing vehicle transmissions that accomplish the government imperatives of increased vehicle efficiency and lower exhaust (greenhouse gaseous) emissions. These exhaust emissions can be regulated or lowered by increasing the fuel economy of a vehicle, and CVTs (continuously variable transmissions), indubitably, play a crucial role in this plan to improve the fuel economy. A continuously variable transmission is an emerging automotive transmission technology that offers a continuum of gear ratios between desired limits. A CVT offers numerous advantages over the conventional multi-step gear transmissions such as …

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Managing Product Line Asset Bases, John Hunt Dec 2006

Managing Product Line Asset Bases, John Hunt

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Product lines are predicated on collecting assets common to the desired product portfolio, commonly known as the asset base. For many product lines, the size of asset base has become large enough to create a variety of difficulties. The techniques for managing large product line asset bases are unaddressed in the literature.
This research presents new techniques that take advantage of asset base characteristics, unavailable in more general collections, to both reduce the number of assets and to organize the asset base that go beyond what is possible with other software collections. The result is an asset base that is …

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A Comparison Of The Zns(Ag) Scintillation Detector To The Silicon Semiconductor Detector For Quantification Of Alpha Radioactivity In Aqueous Solutions, Jennifer Foster Dec 2006

A Comparison Of The Zns(Ag) Scintillation Detector To The Silicon Semiconductor Detector For Quantification Of Alpha Radioactivity In Aqueous Solutions, Jennifer Foster

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A ZnS(Ag) detector was successfully used in the direct detection of alpha particles from aqueous solutions and the results were compared to the passivated ion implanted planar silicon (PIPS) continuous air monitor (CAM) detector. The ZnS(Ag) detector is recommended for on-line detection of gross alpha radioactivity from high-level liquid waste process streams; however, the detector suffers from limitations due to variations in detection efficiency with alpha energies. The beta and gamma interference did not significantly spillover into the alpha region of interest of the ZnS(Ag) detector which provided absolute detection efficiencies of 7.19 ± 0.13%, 5.37 ± 0.02%, and 4.21 …

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Using A Spline To Model The Motion Of A 4-Man Fireteam During Building Clearing Exercises, Marshall Werner Dec 2006

Using A Spline To Model The Motion Of A 4-Man Fireteam During Building Clearing Exercises, Marshall Werner

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This paper examines the problem of tracking positions of a fireteam (4-5 men) as they perform building clearing exercises in order to predict future motion od the team. This was done by examining the team as a single entity rather than 4 or 5 separate entities. A team model was used under the assumption that the team stays together as a group and moves in specific patterns. The model chosen for this experiment was a spline curve. This spline curve allowed for movement in straight lines through hallways as well as curving around corners.

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Path Integral Formulation Of Langeinv Dynamics With Applications To Rare-Event Systems, Bradley Dickson Dec 2006

Path Integral Formulation Of Langeinv Dynamics With Applications To Rare-Event Systems, Bradley Dickson

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In the last decade great efforts have been made to efficiently study the behaviors of rare-event systems. The methods and theories developed in pursuit of this goal are far from unified and are instead applied on a case-by-case basis where one makes a best educated guess as to which approach may afford the greatest chance of studying the rare-event system in question. The work contained here is directed at further development of one of these sets of methods and theories. Specifically, a new theory of dynamics in the Langevin path space is developed with emphasis on generating and sampling Langevin …

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Visualization Of Polymer Processing At The Continuum Level, Jeremy Hicks Dec 2006

Visualization Of Polymer Processing At The Continuum Level, Jeremy Hicks

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Computer animation, coupled with scientific experimentation and modeling, allows scientists to produce detailed visualizations that potentially enable more comprehensive perception of physical phenomena and ultimately, new discoveries. With the use of Maya, an animation and modeling program that incorporates the natural laws of physics to control the behavior of virtual objects in computer animation, data from the modeling of physical processes such as polymer fibers and films can be explored in the visual realm. Currently, few attempts have been made at the continuum level to represent polymer properties via computer animation using advanced graphics. As a result, scientists may be …

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Corruption: The True Cause Of The Resource Curse?, Margie Sharpe Dec 2006

Corruption: The True Cause Of The Resource Curse?, Margie Sharpe

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The theory of the Resource Curse suggests that countries with high levels of natural resources are actually found to possess lower gross domestic products. The source of this disparity is widely debated; however, this analysis suggests that the underlying force preventing such nations from taking advantage of their natural capital abundance is corruption within their economic and governmental systems. In addition, the resource quality is examined to see that it too affects the ability of a nation to change such assets into a higher overall level of national wealth.

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The Effects Of Viscoelastic Behavior On The Operation Of A Delayed Resonator Vibration Absorber, John Cowans Dec 2006

The Effects Of Viscoelastic Behavior On The Operation Of A Delayed Resonator Vibration Absorber, John Cowans

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Delayed resonators have proven to be effective vibration absorbers (VAs) for tracking and canceling the effects of harmonic excitations on a structure. The Delayed Resonator (DR) is selfcontained, as no information from outside of its substructure is required for proper operation. It adjusts for variations in frequency using time-delay and gain as control parameters.
This thesis examines the relationship between viscoelastic (VE) loss mechanisms in systems with DR and the choice of modeling method used to calculate control parameters and determine system stability. It is hypothesized that a VE loss mechanism approximated by a single viscous dashpot may lead to …

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Internal Combustion Engine Cooling Strategies: Theory And Test, John Chastain Dec 2006

Internal Combustion Engine Cooling Strategies: Theory And Test, John Chastain

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Advanced internal combustion engine thermal management systems can enhance overall engine performance through the use of computer controlled cooling system actuators. Existing ground vehicle cooling systems generally have performance limitations due to the fixed behavior of the wax-based thermostat valve and crankshaft dependent operation of the coolant pump and radiator fan. Upgrading the traditional thermostat valve, water pump, and radiator fan with actuators permit real time computer control for improved temperature tracking and reduced power consumption. In this paper, the benefits associated with advanced automotive cooling systems are experimentally investigated. A 4.6L engine with a real-time data acquisition and control …

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An Investigation Of Proportional Thinking Among High School Students, Kirsten Dooley Dec 2006

An Investigation Of Proportional Thinking Among High School Students, Kirsten Dooley

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The National Council of Teachers of Mathematics suggests that formal proportional reasoning instruction take place during grades five through eight (1989). While extensive research has explored both pre-instructional and intra-instructional student proportional thinking strategies, little research has been done on post-instructional proportional thinking strategies used by high-school aged students. As proportional reasoning is fundamental for success in Algebra and other advanced mathematics, it seems relevant to verify that these students retain their reasoning abilities and can apply them in both high school and college mathematical situations.
This study sought to: (1) determine whether high-school students from specific rural, low-income school …

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Financial Aid As A Predictor Of Retention At A Two-Year College, Cheryl Davids Dec 2006

Financial Aid As A Predictor Of Retention At A Two-Year College, Cheryl Davids

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The primary purpose of this study was to determine the likelihood that the type of financial assistance a student receives is a predictor of retention at a two-year college. The institution utilized in the study is a mid-size, public, two-year college in South Carolina. The effects of five distinct types of financial assistance on retention were investigated. The types of financial assistance include Federal Pell Grant, Legislative Incentive for Future Excellence (LIFE) Scholarship, South Carolina Education Lottery (SCEL) Tuition Assistance, a combination of South Carolina Education Lottery Tuition Assistance and Federal Pell Grant, and a combination of Legislative Incentive for …

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Unsupervised Neural Pattern Classifiers For Oral Vowel Pronunciation Of Foreign-Accented Speech, Joseph Hecker Dec 2006

Unsupervised Neural Pattern Classifiers For Oral Vowel Pronunciation Of Foreign-Accented Speech, Joseph Hecker

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This thesis describes the development of unsupervised neural-based pattern classifiers for the training of vowel pronunciations for students learning a foreign language. This paper examines American learners of the French language. A corpus of single word utterances is compiled from a group of native French speakers. Cepstral features are used to train two unsupervised neural pattern classifiers: a self-organizing map and a growing neural gas. The development and justification for the use of these classifiers is presented. The output from the classifier is translated to a bar graph for visual assessment. The degree to which the utterance sounds native is …

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Clemson Commencement Program, December 2006, Clemson University Dec 2006

Clemson Commencement Program, December 2006, Clemson University

Clemson Commencement Programs

No abstract provided.

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