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2011

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Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner Dec 2011

Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner

Theses and Dissertations

This thesis presents the development of a high-resolution ground-based 3D-SAR system and investigates its application to microwave-vegetation studies. The development process of the system is detailed including an enumeration of high-level requirements, discussions on key design issues, and detailed descriptions of the system down to a component level. The system operates on a 5.4 GHz (C-band) signal, provides a synthetic aperture area of 1.7 m x 1.7 m, and offers resolution of 0.75 m x 0.3 m x 0.3 m (range x azimuth x elevation). The system is employed on several trees with varying physical characteristics. The resulting imagery demonstrates …

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A Conceptual Framework For Student Understanding Of Logarithms, Heather Rebecca Ambler Williams Dec 2011

A Conceptual Framework For Student Understanding Of Logarithms, Heather Rebecca Ambler Williams

Theses and Dissertations

In the past, frameworks for what it means for students to understand elementary mathematical concepts like addition have been well-researched. These frameworks are useful for identifying what students must understand to have a good grasp of the concept. Few such research-based frameworks exist for secondary mathematical topics. The intent of this study was to create such a framework for what it means for students to understand logarithms, a topic that has been under-researched up to this point. Four task-based interviews were conducted with each of four different preservice secondary mathematics teachers in order to test a preliminary framework I had …

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An Updated Gps Velocity Field For Puerto Rico And The Virgin Islands: Constraints On Tectonic Setting And Internal-Deformation, Desmond Kelvin Ihemedu Dec 2011

An Updated Gps Velocity Field For Puerto Rico And The Virgin Islands: Constraints On Tectonic Setting And Internal-Deformation, Desmond Kelvin Ihemedu

Earth & Environmental Sciences Theses - Archive

Puerto Rico and the northern Virgin Islands define the eastern end of the Greater Antilles, while the Puerto Rico trench and the Muertos Trough define the northern and the southern limits of the North American - Caribbean plate boundary zone. Three microplates have been defined: (1) Gonave, to the west; (2) Hispaniola, at the center; and (3) Puerto Rico and the northern Virgin Islands (PRVI) at the eastern end. Global Positioning System (GPS) geodesy was previously conducted in this region from 1994 to 2003. It was concluded that the locus of the highest permissible on-surface deformation in Puerto Rico and …

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Flyer News, Vol. 59, No. 20 (Dec. 9, 2011), University Of Dayton Dec 2011

Flyer News, Vol. 59, No. 20 (Dec. 9, 2011), University Of Dayton

Flyer News

Student-run newspaper of the University of Dayton.

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Quantifying Physiological Responses Of Beef Cattle Using A Tympanic Temperature Measurement Device, Jacob John Mayer Dec 2011

Quantifying Physiological Responses Of Beef Cattle Using A Tympanic Temperature Measurement Device, Jacob John Mayer

Theses and Dissertations

The primary goals of this research were to develop an improved design for measuring tympanic temperature in groups of beef cattle, determine the ideal operating parameters of the new device, and to verify its effectiveness in a research application. Development of the continuous tympanic temperature logger (CTTL) consisted of two steps: identifying a small temperature logger capable of adequate data storage and constructing a probe to hold the logger and fit in the ear canal of a bovine animal. The minimum sampling interval needed to measure tympanic temperature in beef cattle was calculated using Fourier analysis. In addition, the differences …

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An Investigative Study Of The Influence Of Religion On Help Seeking Behaviors In The Field Of Mental Health, Kristen Darroch Dec 2011

An Investigative Study Of The Influence Of Religion On Help Seeking Behaviors In The Field Of Mental Health, Kristen Darroch

Theses and Dissertations

The present study was undertaken to assess the influence of religion on help seeking behaviors regarding mental health. Participants (n = 167) were volunteers from three different churches of Christian denominations who anonymously completed questionnaires regarding their religiosity and their attitude toward seeking help from a mental health professional. Analysis of the data found that subjects who belonged to liberal denominations of Christianity were more likely to seek help from a mental health professional for mental health issues than subjects belonging to more traditionally conservative denominations of Christianity. The study also found that subjects belonging to conservative denominations of Christianity …

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Educating Mexico In Emilio Fernández's Río Escondido And Rosario Castellanos's Balún Canán, David Scott Dalton Dec 2011

Educating Mexico In Emilio Fernández's Río Escondido And Rosario Castellanos's Balún Canán, David Scott Dalton

Theses and Dissertations

Following the bloody Revolution of 1910-1917, Mexican leaders took a great interest in rebuilding their devastated, war-torn country. In an attempt to further national unity, the post-Revolutionary regime sought to construct a unified, national identity. Many officials, such as José Vasconcelos, Mexico's first Secretario de Educación, viewed education as one of the keys to redeeming the nation. These government officials, empowered by their ideals and their sense of civic duty, worked to extend educational benefits to even the most overlooked segments of Mexican society. This thesis will examine two fictional texts that consider these efforts to transform and unify …

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Biophotonic Imaging As A Novel Approach To Study Infectious Diseases In The Bovine, Jaime E. Curbelo Rodríguez Dec 2011

Biophotonic Imaging As A Novel Approach To Study Infectious Diseases In The Bovine, Jaime E. Curbelo Rodríguez

Theses and Dissertations

Conventional bacteriological methods to establish bacterial burden and distribution in infected tissues in vivo animal models typically require extensive bacteriological procedures and therefore are time consuming. An alternative approach has been suggested to use optical markers, such as luciferases, to labeled pathogens and monitor their progress and distribution in real time. The objective of the work presented in this document was to validate the use of Biophotonic Imaging (BI) through in vitro studies as a first step toward the development of in vivo models to study infectious disease in the bovine. For example, the feasibility of detecting bioluminescent Escherichia coli …

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Assessing The Effects Of Toxic Synthetic Organic Compounds On Activated Sludge Communities, Kristopher Michael Lightsey Dec 2011

Assessing The Effects Of Toxic Synthetic Organic Compounds On Activated Sludge Communities, Kristopher Michael Lightsey

Theses and Dissertations

The recent technological advances in environmental monitoring coupled with the increasingly stringent effluent requirements being placed on waste treatment systems makes it vital to have a more complete understanding of how specific compounds in waste streams can impact wastewater treatment processes. Since activated sludge processes are recognized as one of the most often applied technologies in wastewater treatment, this study assesses the impacts of select toxic synthetic organic compounds (SOCs) on the activated sludge communities in two types of wastewater treatment reactors: a completely-mixed activated sludge reactor (CMAS) and a sequencing batch reactor (SBR). Commonly applied activated sludge monitoring parameters, …

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Modeling Carbon Fiber Reinforced Polymeric Composite Laminates For Piezoelectric Morphing Structures, Darryl Vincent Murray Dec 2011

Modeling Carbon Fiber Reinforced Polymeric Composite Laminates For Piezoelectric Morphing Structures, Darryl Vincent Murray

Theses and Dissertations

Thin unsymmetric carbon fiber reinforced polymeric(CFRP) composite laminates are examined for use of morphing structures using piezoelectric actuation. During fabrication, unsymmetric laminates are able to deform to more than one post-cure room temperature shape. Thin cross-ply laminates will deform to a cylindrical post-cure room temperature shape while thicker non-cross-ply laminates will deform to a saddle shape. Predictions of the deformed post-cure shape will be made by modeling the cure process using analytical and numerical. These models will then serve as expectations for experimental tests. Modeling the fabrication process allowed for characterizing important data such as residual stresses from the cure …

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Modified Network Simplex Method To Solve A Sheltering Network Planning And Management Problem, Lingfeng Li Dec 2011

Modified Network Simplex Method To Solve A Sheltering Network Planning And Management Problem, Lingfeng Li

Theses and Dissertations

This dissertation considers sheltering network planning and operations for natural disaster preparedness and responses with a two-stage stochastic program. The first phase of the network design decides the locations, capacities and held resources of new permanent shelters. Both fixed costs for building a new permanent shelter and variable costs based on capacity are considered. Under each disaster scenario featured by the evacuee demand and transportation network condition, the flows of evacuees and resources to shelters, including permanent and temporary ones, are determined in the second stage to minimize the transportation and shortage/surplus costs. Typically, a large number of scenarios are …

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Optimal Operation Of Multi-Terminal Vsc Based Mvdc Shipboard Power System, Sandeep Yeleti Dec 2011

Optimal Operation Of Multi-Terminal Vsc Based Mvdc Shipboard Power System, Sandeep Yeleti

Theses and Dissertations

The Medium Voltage DC (MVDC) architecture of shipboard power system (SPS) with higher power density and enhanced power control is seen as a future prospect in warships by US Navy. Optimal operation of SPS is essential to enable efficient power and energy usage in the tightly coupled and power limited systems. It helps in obtaining adequate and reliable power supply by rescheduling generator output and energy storage devices for different operating scenarios and can also ensure power supply to critical loads during fault conditions. The self-commutated Voltage Source Converters (VSCs) with high dynamic performance and independent control over the real …

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Pedestrian Dynamics: Modeling And Analyzing Cognitive Processes And Traffic Flows To Evaluate Facility Service Level, Hohyun Lee Dec 2011

Pedestrian Dynamics: Modeling And Analyzing Cognitive Processes And Traffic Flows To Evaluate Facility Service Level, Hohyun Lee

Theses and Dissertations

Walking is the oldest and foremost mode of transportation through history and the prevalence of walking has increased. Effective pedestrian model is crucial to evaluate pedestrian facility service level and to enhance pedestrian safety, performance, and satisfaction. The objectives of this study were to: (1) validate the efficacy of utilizing queueing network model, which predicts cognitive information processing time and task performance; (2) develop a generalized queueing network based cognitive information processing model that can be utilized and applied to construct pedestrian cognitive structure and estimate the reaction time with the first moment of service time distribution; (3) investigate pedestrian …

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Static And Free Vibration Analyses Of Composite Shells Based On Different Shell Theories, Ebrahim Asadi Dec 2011

Static And Free Vibration Analyses Of Composite Shells Based On Different Shell Theories, Ebrahim Asadi

Theses and Dissertations

Equations of motion with required boundary conditions for doubly curved deep and thick composite shells are shown using two formulations. The first is based upon the formulation that was presented initially by Rath and Das (1973, J. Sound and Vib.) and followed by Reddy (1984, J. Engng. Mech. ASCE). In this formulation, plate stiffness parameters are used for thick shells, which reduced the equations to those applicable for shallow shells. This formulation is widely used but its accuracy has not been completely tested. The second formulation is based upon that of Qatu (1995, Compos. Press. Vessl. Indust.; 1999, Int. J. …

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Static And Vibration Analysis Of Thick Generally Laminated Composite Deep Curved Beams, Mehdi Hajianmaleki Dec 2011

Static And Vibration Analysis Of Thick Generally Laminated Composite Deep Curved Beams, Mehdi Hajianmaleki

Theses and Dissertations

A rigorous first order shear deformation theory (FSDT) is employed along with modified ABD parameters to analyze static and free vibration behavior of generally laminated beams and shafts. Different approaches for calculating composite beam stiffness parameters have been considered and the most accurate one that accounts for material couplings have been used to analyze static and free vibration behaviors of straight beams with different laminates and boundary conditions. In order to analyze curved beams, the term (1+z/R) is exactly integrated into ABD parameters formulation and an equivalent modulus of elasticity is used instead of traditional stiffness terms to account for …

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Lifetime Characteristics Of Magnet Wire Mw 16-C Under Ac, Dc Voltages, And High Temperatures, Manasi Pramod Gadre Dec 2011

Lifetime Characteristics Of Magnet Wire Mw 16-C Under Ac, Dc Voltages, And High Temperatures, Manasi Pramod Gadre

Theses and Dissertations

Polyimide is one of the most heat resistant polymers with high electric breakdown strength, good mechanical properties, and chemical resistance. Polyimide is used in severe environmental condition. Polyimide is commonly applied as electrical insulation in a fine gauge of invertered motor windings and in high voltage coils of encapsulated fly-back transformers. The wire insulation may be exposed to multi-stresses like ac, dc high voltages, temperatures etc. In this thesis, magnet wire insulation properties under multiple stresses are studied under ac, dc voltages and high temperatures. Accelerated degradation test is used to do study of Life -time characteristics of Magnetic wire …

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Machine Learning Driven Model Inversion Methodology To Detect Reniform Nematodes In Cotton, Pavan Kumar Palacharla Dec 2011

Machine Learning Driven Model Inversion Methodology To Detect Reniform Nematodes In Cotton, Pavan Kumar Palacharla

Theses and Dissertations

Rotylenchulus reniformis is a nematode species affecting the cotton crop and quickly spreading throughout the southeastern United States. Effective use of nematicides at a variable rate is the only economic counter measure. It requires the intraield variable nematode population, which in turn depends on the collection of soil samples from the field and analyzing them in the laboratory. This process is economically prohibitive. Hence estimating the nematode infestation on the cotton crop using remote sensing and machine learning techniques which are cost and time effective is the motivation for this study. In the current research, the concept of multi-temporal remote …

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The Effect Of Material And Processing On The Impact Strength Of Vapor-Grown Carbon Nanofiber/Vinyl Ester Composites, Glenn William Torres Dec 2011

The Effect Of Material And Processing On The Impact Strength Of Vapor-Grown Carbon Nanofiber/Vinyl Ester Composites, Glenn William Torres

Theses and Dissertations

A design of experiments methodology was used to investigate the effect of vaporgrown carbon nanofiber (VGCNF) weight fraction, high-shear mixing time, and ultrasonication time on the Izod impact strength of vinyl ester (VE) based nanocomposites. A response surface model (RSM) was developed for predicting impact strengths using a regression analysis approach. The RSM predicts a maximum increase in impact strength of 18% at a VGCNF weight fraction of 0.17 parts per hundred parts resin (phr) (a volume percent of ~0.1) and 100 min high-shear mixing when compared to that of neat VE. The impact strength predictions show an initial increase …

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The Bg News December 9, 2011, Bowling Green State University Dec 2011

The Bg News December 9, 2011, Bowling Green State University

BG News (Student Newspaper)

The BGSU campus student newspaper. December 9, 2011. Volume 102-Issue 50.

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A Framework For Studying The Physical Degradation Characteristics Of Dvds And Their Relationship To Digital Errors, Brian K. Saville Dec 2011

A Framework For Studying The Physical Degradation Characteristics Of Dvds And Their Relationship To Digital Errors, Brian K. Saville

Theses and Dissertations

The methods used to store data on DVD-R discs have been proven to work over the last 15 years. However, there has been a growing concern that these discs will be outlasted by the paper records they were meant to replace. The data on a DVD-R is stored as optical contrasts which have the potential to be misread and even damaged. This damage may occur either on the surface or internally to the disc, especially on the recording layer itself. The literature is saturated with studies attempting to determine the time period in which discs may fail and what the …

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The Original Footloose: How President Murlin Pushed Back Against Traditional Depauw Methodism, Sam Spahn Dec 2011

The Original Footloose: How President Murlin Pushed Back Against Traditional Depauw Methodism, Sam Spahn

Student Research

No abstract provided.

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Cross-Entropy Approaches To Software Forensics: Source Code Authorship Identification, James Thomas Stinson Dec 2011

Cross-Entropy Approaches To Software Forensics: Source Code Authorship Identification, James Thomas Stinson

Theses and Dissertations

Identification of source code authorship can be a useful tool in the areas of security and forensic investigation by helping to create corroborating evidence that may send a suspected cyber terrorist, hacker, or malicious code writer to jail. When applied to academia, it can also prove a useful tool for professors who suspect students of academic dishonesty, plagiarism, or modification of source code related to programming assignments. The purpose of this dissertation is to determine whether or not cross-entropy approaches to source code authorship analysis will succeed in predicting the correct author of a given piece of source code. If …

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Investigating How Equating Guidelines For Screening And Selecting Common Items Apply When Creating Vertically Scaled Elementary Mathematics Tests, Maria Assunta Hardy Dec 2011

Investigating How Equating Guidelines For Screening And Selecting Common Items Apply When Creating Vertically Scaled Elementary Mathematics Tests, Maria Assunta Hardy

Theses and Dissertations

Guidelines to screen and select common items for vertical scaling have been adopted from equating. Differences between vertical scaling and equating suggest that these guidelines may not apply to vertical scaling in the same way that they apply to equating. For example, in equating the examinee groups are assumed to be randomly equivalent, but in vertical scaling the examinee groups are assumed to possess different levels of proficiency. Equating studies that examined the characteristics of the common-item set stress the importance of careful item selection, particularly when groups differ in ability level. Since in vertical scaling cross-level ability differences are …

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Fall Commencement Ceremonies, University Of North Florida Dec 2011

Fall Commencement Ceremonies, University Of North Florida

Commencement Printed Materials

Program for the Fall Commencement ceremonies.

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Assessing And Modeling Student Academic Practices And Performance In First-Year Mathematics Courses In Higher Education, Kim Ward, Chantal Larose Dec 2011

Assessing And Modeling Student Academic Practices And Performance In First-Year Mathematics Courses In Higher Education, Kim Ward, Chantal Larose

Higher Learning Research Communications

Objectives: This research brief explores literature addressing developmental education to identify successful interventions in first-year math courses in higher education. Our goal is to describe the relationship between students’ academic practices and their final course grade in their first-year math courses. Method: Data on 3,249 students have been gathered and analyzed using descriptive statistics and predicative analytics. We describe the Math program, which includes a supplemental support component, and the environment under which it was created. We then examine the behavior between students’ participation in supplemental support and their academic performance. Results: We used classification and regression tree algorithms to …

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Research Universities As Engines Of Economic Growth: How Do Research Universities Impact Regional Economic Growth?, Stephanie Arnette Pink Dec 2011

Research Universities As Engines Of Economic Growth: How Do Research Universities Impact Regional Economic Growth?, Stephanie Arnette Pink

Theses and Dissertations

As a result of the 2008-2010 economic crisis as well as continuing efforts to redevelop and revitalize local economies, public administrators across America are challenged with the task of developing methods to sustain their economies. According to Florida (2002) economic growth today is contingent upon a locality’s ability to attract a certain group of people, particularly those of the “creative class”. Furthermore, Florida et al., (2006), assert that universities are key contributors to regional development in their ability to attract creative class individuals into a community. Contrary to the assertion that the creative class is a prerequisite for economic growth, …

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On The Problem Of Arbitrary Projections Onto A Reduced Discrete Set Of States With Applications To Mean First Passage Time Problems, Katja Biswas Dec 2011

On The Problem Of Arbitrary Projections Onto A Reduced Discrete Set Of States With Applications To Mean First Passage Time Problems, Katja Biswas

Theses and Dissertations

This dissertation presents a theoretical study of arbitrary discretizations of general nonequilibrium and non-steady-state systems. It will be shown that, without requiring the partitions of the phase-space to fulfill certain assumptions, such as culminating in Markovian partitions, a Markov chain can be constructed which has the same macro-change of probability of the occupation of the states as the original process. This is true for any classical and semiclassical system under any discrete or continuous, deterministic or stochastic, Markovian or non-Markovian dynamics. Restricted to classical and semi-classical systems, a formalism is developed which treats the projection of arbitrary (multidimensional) complex systems …

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Development Of Sub Models For A Phenomenological Investigation Of Diesel Engine Combustion, Lu Qiu Dec 2011

Development Of Sub Models For A Phenomenological Investigation Of Diesel Engine Combustion, Lu Qiu

Theses and Dissertations

Various sub models of a multi-zone phenomenological model are developed by incorporating Dec’s conceptual model and Siebers’ mixing limited theory and validated with experiments. The spray penetration model, liquid length model and lift-off length model are verified with experiment data. The ignition delay model is then validated with experiment data at different injection timings and loads. The air entrainment model is based on Siebers’ jet theory. Sub models for the premixed heat release rate and diffusion burn rate are also included. The overall phenomenological model is at first used to match the motoring pressure curve. The important sub models are …

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Discrete Particle Swarm Optimization Algorithm For Optimal Operation Of Reconfigurable Distribution Grids, Wenqin Xue Dec 2011

Discrete Particle Swarm Optimization Algorithm For Optimal Operation Of Reconfigurable Distribution Grids, Wenqin Xue

Theses and Dissertations

Optimization techniques are widely applied in the power system planning and operation to achieve more efficient and reliable power supply. With the introduction of new technologies, the complexity of today’s power system increased significantly. Intelligent optimization techniques, such as Particle Swarm Optimization (PSO), can efficiently deal with the new challenges compared to conventional optimization techniques. This thesis presents applications of discrete PSO in two specific environments. The first one is for day-ahead optimal scheduling of the reconfigurable gird with distributed energy resources. The second one is a two-step method for rapid reconfiguration of shipboard power system. Effective techniques, such as …

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Power Supply On Chip Dc-Dc Converter Identification Using Black-Box Modeling Techniques, Charles Craig Bilberry Dec 2011

Power Supply On Chip Dc-Dc Converter Identification Using Black-Box Modeling Techniques, Charles Craig Bilberry

Theses and Dissertations

With recent developments in power conversion technologies and market trends that are driving those technologies toward further miniaturization and greater integration, the need for verifying an empirically based modeling methodology for proprietary power converters such as Power Supply on Chip (PwrSoC) products has risen significantly. This need motivates the investigation of black-box models which require little or no knowledge of the internal workings of a system, for those areas of industry adopting PwrSoC technology as a point-of-load solution. This thesis reports a black-box modeling method tailored to accommodate but not limited to the requirements of a specific commercially available PwrSoC …

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