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Near-Road Dispersion Modeling Of Mobile Source Air Toxics (Msats) In Florida, Kurt Westerlund Jan 2013

Near-Road Dispersion Modeling Of Mobile Source Air Toxics (Msats) In Florida, Kurt Westerlund

Electronic Theses and Dissertations

There is a growing public concern that emissions of mobile source air toxics (MSATs) from motor vehicles may pose a threat to human health. At present, no state or federal agencies require dispersion modeling of these compounds, but many agencies are concerned about potential future requirements. Current air pollution professionals are familiar with Federal Highway Administration (FHWA) and U.S. Environmental Protection Agency (EPA) requirements for dispersion modeling to produce predicted concentrations for comparison with appropriate standards. This research examined a method in which the potential near-road concentrations of MSATs were calculated. It was believed that by assessing MSATs in much …

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A Compiler-Based Framework For Automatic Extraction Of Program Skeletons For Exascale Hardware/Software Co-Design, Amruth Rudraiah Dakshinamurthy Jan 2013

A Compiler-Based Framework For Automatic Extraction Of Program Skeletons For Exascale Hardware/Software Co-Design, Amruth Rudraiah Dakshinamurthy

Electronic Theses and Dissertations

The design of high-performance computing architectures requires performance analysis of largescale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this paper is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed for …

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Developing A Group Decision Support System (Gdss) For Decision Making Under Uncertainty, Soroush Mokhtari Jan 2013

Developing A Group Decision Support System (Gdss) For Decision Making Under Uncertainty, Soroush Mokhtari

Electronic Theses and Dissertations

Multi-Criteria Decision Making (MCDM) problems are often associated with tradeoffs between performances of the available alternative solutions under decision making criteria. These problems become more complex when performances are associated with uncertainty. This study proposes a stochastic MCDM procedure that can handle uncertainty in MCDM problems. The proposed method coverts a stochastic MCDM problem into many deterministic ones through a Monte-Carlo (MC) selection. Each deterministic problem is then solved using a range of MCDM methods and the ranking order of the alternatives is established for each deterministic MCDM. The final ranking of the alternatives can be determined based on winning …

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Discriminative Dictionary Learning With Spatial Constraints, Muhammad Nazar Khan Jan 2013

Discriminative Dictionary Learning With Spatial Constraints, Muhammad Nazar Khan

Electronic Theses and Dissertations

In this thesis, we investigate the use of dictionary learning for discriminative tasks on natural images. Our contributions can be summarized as follows: • We introduce discriminative deviation based learning to achieve principled handling of the reconstruction-discrimination tradeoff that is inherent to discriminative dictionary learning. • Since natural images obey a strong smoothness prior, we show how spatial smoothness constraints can be incorporated into the learning formulation by embedding dictionary learning into Conditional Random Field (CRF) learning. We demonstrate that such smoothness constraints can lead to state-of-the-art performance for pixel-classification tasks. • Finally, we lay down the foundations of super-latent …

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Modeling Of Socio-Economic Factors And Adverse Events In An Active War Theater By Using A Cellular Automata Simulation Approach, Halil Bozkurt Jan 2013

Modeling Of Socio-Economic Factors And Adverse Events In An Active War Theater By Using A Cellular Automata Simulation Approach, Halil Bozkurt

Electronic Theses and Dissertations

Department of Defense (DoD) implemented Human Social Cultural and Behavior (HSCB) program to meet the need to develop capability to understand, predict and shape human behavior among different cultures by developing a knowledge base, building models, and creating training capacity. This capability will allow decision makers to subordinate kinetic operations and promote non-kinetic operations to govern economic programs better in order to initiate efforts and development to address the grievances among the displeased by adverse events. These non-kinetic operations include rebuilding indigenous institutions’ bottom-up economic activity and constructing necessary infrastructure since the success in non-kinetic operations depends on understanding and …

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Using Freebase, An Automatically Generated Dictionary, And A Classifier To Identify A Person's Profession In Tweets, Abraham Hall Jan 2013

Using Freebase, An Automatically Generated Dictionary, And A Classifier To Identify A Person's Profession In Tweets, Abraham Hall

Electronic Theses and Dissertations

Algorithms for classifying pre-tagged person entities in tweets into one of eight profession categories are presented. A classifier using a semi-supervised learning algorithm that takes into consideration the local context surrounding the entity in the tweet, hash tag information, and topic signature scores is described. In addition to the classifier, this research investigates two dictionaries containing the professions of persons. These two dictionaries are used in their own classification algorithms which are independent of the classifier. The method for creating the first dictionary dynamically from the web and the algorithm that accesses this dictionary to classify a person into one …

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Development Of Nitrogen Concentration During Cryomilling Of Aluminum Composites, Clara Hofmeister Jan 2013

Development Of Nitrogen Concentration During Cryomilling Of Aluminum Composites, Clara Hofmeister

Electronic Theses and Dissertations

The ideal properties of a structural material are light weight with extensive strength and ductility. A composite with high strength and tailorable ductility was developed consisting of nanocrystalline AA5083, boron carbide and coarser grained AA5083. The microstructure was determined through optical microscopy and transmission electron microscopy. A technique was developed to determine the nitrogen concentration of an AA5083 composite from secondary ion mass spectrometry utilizing a nitrogen ionimplanted standard. Aluminum nitride and amorphous nitrogen-rich dispersoids were found in the nanocrystalline aluminum grain boundaries. Nitrogen concentration increased as a function of cryomilling time up to 72hours. A greater nitrogen concentration resulted …

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Automatically Acquiring A Semantic Network Of Related Concepts, Sean Szumlanski Jan 2013

Automatically Acquiring A Semantic Network Of Related Concepts, Sean Szumlanski

Electronic Theses and Dissertations

We describe the automatic acquisition of a semantic network in which over 7,500 of the most frequently occurring nouns in the English language are linked to their semantically related concepts in the WordNet noun ontology. Relatedness between nouns is discovered automatically from lexical co-occurrence in Wikipedia texts using a novel adaptation of an information theoretic inspired measure. Our algorithm then capitalizes on salient sense clustering among these semantic associates to automatically disambiguate them to their corresponding WordNet noun senses (i.e., concepts). The resultant concept-to-concept associations, stemming from 7,593 target nouns, with 17,104 distinct senses among them, constitute a large-scale semantic …

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A System Dynamics Model For Manpower And Technology Implementation Trade-Off And Cost Estimation, Hong Jiang Jan 2013

A System Dynamics Model For Manpower And Technology Implementation Trade-Off And Cost Estimation, Hong Jiang

Electronic Theses and Dissertations

The U.S. Navy has been confronted with budget cuts and constraints during recent years. This reduction in budget compels the U.S. Navy to limit the number of manpower and personnel to control costs. Reducing the total ownership cost (TOC) has become a major topic of interest for the Navy as plans are made for current and future fleets. According to the U.S. Government Accountability Office (GAO, 2003), manpower is the most influential component of determining the life cycle cost of a ship. The vast majority of the TOC is comprised of operating and support (O&S) costs which account for approximately …

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Recognition Of Complex Events In Open-Source Web-Scale Videos: Features, Intermediate Representations And Their Temporal Interactions, Subhabrata Bhattacharya Jan 2013

Recognition Of Complex Events In Open-Source Web-Scale Videos: Features, Intermediate Representations And Their Temporal Interactions, Subhabrata Bhattacharya

Electronic Theses and Dissertations

Recognition of complex events in consumer uploaded Internet videos, captured under realworld settings, has emerged as a challenging area of research across both computer vision and multimedia community. In this dissertation, we present a systematic decomposition of complex events into hierarchical components and make an in-depth analysis of how existing research are being used to cater to various levels of this hierarchy and identify three key stages where we make novel contributions, keeping complex events in focus. These are listed as follows: (a) Extraction of novel semi-global features – firstly, we introduce a Lie-algebra based representation of dominant camera motion …

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Study Of The Effect Of Surface Morphology On Mass Transfer And Fouling Behavior Of Reverse Osmosis And Nanofiltration Membrane Processes, Yuming Fang Jan 2013

Study Of The Effect Of Surface Morphology On Mass Transfer And Fouling Behavior Of Reverse Osmosis And Nanofiltration Membrane Processes, Yuming Fang

Electronic Theses and Dissertations

Reverse osmosis (RO) and nanofiltration (NF) membranes are pressure driven, diffusion controlled process. The influence of surface characteristics on membrane process performance is considered significant and is not well understood. Current mass transport models generally assume constant mass transfer coefficients (MTCs) based on a homogeneous surface. This work evaluated mass transfer processes by incorporating surface morphology into a diffusion-based model assuming MTCs are dependent on the thickness variation of the membrane’s active layer. To mathematically create such a surface layer, Gaussian random vectors embedded in a software system (MATLAB) were used to generate a three-dimensional ridge and valley active layer …

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The Measurement Of Motivation: Examining The Measurement Properties Of The Motivation Assessment System, Daniel Schmerling Jan 2013

The Measurement Of Motivation: Examining The Measurement Properties Of The Motivation Assessment System, Daniel Schmerling

Electronic Theses and Dissertations

The current study investigated the Pritchard-Ashwood (P-A) Theory of Motivation (Pritchard & Ashwood, 2008) by examining a measure of P-A Theory labeled the Motivation Assessment System (MAS). P-A Theory combines prior motivation theories such as expectancy theory, goal setting theory, justice theory, and needs theory and consolidates them into one integrated theory of motivation. In essence, P-A theory posits that one’s motivation is determined by four perceptions, including the extent to which one believes: (a) his/her actions will lead to results, (b) his/her results will lead to positive evaluations, (c) his/her evaluations will lead to positive outcomes, and (d) his/her …

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Hjb Equation And Statistical Arbitrage Applied To High Frequency Trading, Yonggi Park Jan 2013

Hjb Equation And Statistical Arbitrage Applied To High Frequency Trading, Yonggi Park

Electronic Theses and Dissertations

In this thesis we investigate some properties of market making and statistical arbitrage applied to High Frequency Trading (HFT). Using the Hamilton-Jacobi-Bellman(HJB) model developed by Guilbaud, Fabien and Pham, Huyen in 2012, we studied how market making works to obtain optimal strategy during limit order and market order. Also we develop the best investment strategy through Moving Average, Exponential Moving Average, Relative Strength Index, Sharpe Ratio.

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Nano-Particles In Multi-Scale Composites And Ballistic Applications, Jason Gibson Jan 2013

Nano-Particles In Multi-Scale Composites And Ballistic Applications, Jason Gibson

Electronic Theses and Dissertations

Carbon nanotubes, graphene and nano sized core shell rubber particles have all been extensively researched for their capability to improve mechanical properties of thermoset resins. However, there has been a lack of research on their evaluation for energy absorption in high velocity impact scenarios, and the fundamental mechanics of their failure mechanisms during highly dynamic stress transfer through the matrix. This fundamental research is essential for laying the foundation for improvement in ballistic performance in composite armor. In hard armor applications, energy absorption is largely accomplished through delamination between plies of the composite laminate. This energy absorption is accomplished through …

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Defining A Stakeholder-Relative Model To Measure Academic Department Efficiency At Achieving Quality In Higher Education, Federica Robinson-Bryant Jan 2013

Defining A Stakeholder-Relative Model To Measure Academic Department Efficiency At Achieving Quality In Higher Education, Federica Robinson-Bryant

Electronic Theses and Dissertations

In a time of strained resources and dynamic environments, the importance of effective and efficient systems is critical. This dissertation was developed to address the need to use feedback from multiple stakeholder groups to define quality and assess an entity’s efficiency at achieving such quality. A decision support model with applicability to diverse domains was introduced to outline the approach. Three phases, (1) quality model development, (2) input-output selection and (3) relative efficiency assessment, captured the essence of the process which also delineates the approach per tool applied. This decision support model was adapted in higher education to assess academic …

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Mode-Division Multiplexed Transmission In Few-Mode Fibers, Neng Bai Jan 2013

Mode-Division Multiplexed Transmission In Few-Mode Fibers, Neng Bai

Electronic Theses and Dissertations

As a promising candidate to break the single-mode fiber capacity limit, mode-division multiplexing (MDM) explores the spatial dimension to increase transmission capacity in fiberoptic communication. Two linear impairments, namely loss and multimode interference, present fundamental challenges to implementing MDM. In this dissertation, techniques to resolve these two issues are presented. To de-multiplex signals subject to multimode interference in MDM, Multiple-InputMultiple-Output (MIMO) processing using adaptive frequency-domain equalization (FDE) is proposed and investigated. Both simulations and experiments validate that FDE can reduce the algorithmic complexity significantly in comparison with the conventional time-domain equalization (TDE) while achieving similar performance as TDE. To further …

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Development Of Thulium Fiber Lasers For High Average Power And High Peak Power Operation, Robert Sims Jan 2013

Development Of Thulium Fiber Lasers For High Average Power And High Peak Power Operation, Robert Sims

Electronic Theses and Dissertations

High power thulium fiber lasers are useful for a number of applications in both continuous-wave and pulsed operating regimes. The use of thulium as a dopant has recently gained interest due to its large bandwidth, possibility of high efficiency, possibility of high power and long wavelength ~1.8 – 2.1 μm. The longer emission wavelength of Tm-doped fiber lasers compared to Yb- and/or Er-doped fiber lasers creates the possibility for higher peak power operation due to the larger nonlinear thresholds and reduced nonlinear phase accumulation. One primary interest in Tm-doped fiber lasers has been to scale to high average powers; however, …

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Parental Beliefs And Attitudes On Enrollment In A Dual Language Program At An Elementary School, Leah Delorenzo Jan 2013

Parental Beliefs And Attitudes On Enrollment In A Dual Language Program At An Elementary School, Leah Delorenzo

Electronic Theses and Dissertations

In the 2010-2011 school year, there were almost a quarter of a million English language learners (ELLs) enrolled in Florida public schools (Florida Department of Education, 2011), most of whom were placed in mainstream schools with segregated language remediation. Dual language education (DLE) programs offer developmental opportunities in two languages that mainstream schools cannot. The purpose of this research was to identify parental attitudes toward immersion programs and define the reasons that parents enroll their children in DLEs. Sixty participants completed a questionnaire sent home from their student's DLE. The study data included biographical information, statements depicting the reasons for …

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Meme World Syndrome: A Critical Discourse Analysis Of The First World Problems And Third World Success Internet Memes, Robert Chandler Jan 2013

Meme World Syndrome: A Critical Discourse Analysis Of The First World Problems And Third World Success Internet Memes, Robert Chandler

Electronic Theses and Dissertations

This thesis applies the theory and method of Critical Discourse Analysis (CDA) to examine the ideological components of the First World Problems (FWP) and Third World Success (TWS) Internet memes. Drawing on analytical concepts from CDA and related perspectives, such as multimodal discourse analysis and social semiotics, the paper analyzes the visual and textual elements of a sample of the FWP and TWS memes. The paper argues that the text and images featured in the memes are ideologically salient and discursively construct oppositional binaries between “us” and “them” in terms of wealth disparity.

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The Implications Of A High Academic Ability Learning Environment On Third Grade Gifted Students' Academic Achievement In Florida Public Schools, Julie Cady Jan 2013

The Implications Of A High Academic Ability Learning Environment On Third Grade Gifted Students' Academic Achievement In Florida Public Schools, Julie Cady

Electronic Theses and Dissertations

The purpose of this two year study was to investigate the implications of a high academic ability learning environment on the achievement scores of third grade gifted students who attended the Florida Brevard County Public School System. Learning environment was defined by the students’ academic ability level, whether high academic ability or heterogeneous academic ability, and for this study was the independent variable. Academic achievement, as measured by the 2011 and the 2012 Florida Comprehensive Assessment Test® 2.0 (FCAT 2.0) Mathematics and Reading Developmental Scale Scores (DSS), was the dependent variable. Other student data such as gender and socioeconomic status …

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Optimization Problem In Single Period Markets, Tian Jiang Jan 2013

Optimization Problem In Single Period Markets, Tian Jiang

Electronic Theses and Dissertations

There had been a number of researches that investigated on the security market without transaction costs. The focus of this research is in the area that when the security market with transaction costs is fair and in such fair market how one chooses a suitable portfolio to optimize the financial goal. The research approach adopted in this thesis includes linear algebra and elementary probability. The thesis provides evidence that we can maximize expected utility function to achieve our goal (maximize expected return under certain risk tolerance). The main conclusions drawn from this study are under certain conditions the security market …

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Absorptive And Refractive Optical Nonlinearities In Organic Molecules And Semiconductors, Davorin Peceli Jan 2013

Absorptive And Refractive Optical Nonlinearities In Organic Molecules And Semiconductors, Davorin Peceli

Electronic Theses and Dissertations

The main purpose of this dissertation to investigate photophysical properties, third order nonlinearity and free carrier absorption and refraction in organic materials and semiconductors. Special emphasis of this dissertation is on characterization techniques of molecules with enhanced intersystem crossing rate and study of different approaches of increasing triplet quantum yield in organic molecules. Both linear and nonlinear characterization methods are described. Linear spectroscopic characterization includes absorption, fluorescence, quantum yield, anisotropy, and singletoxygen generation measurements. Nonlinear characterization, performed by picosecond and femtosecond laser systems (single and double pump-probe and Z-scan measurements), includes measurements of the triplet quantum yields, excited-state absorption, two-photon …

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Training For Decision Making In Complex Environments: Instructional Methods And Individual Differences, Jessica Ray Jan 2013

Training For Decision Making In Complex Environments: Instructional Methods And Individual Differences, Jessica Ray

Electronic Theses and Dissertations

Increased technology reliance along with today’s global fast paced society has produced increasingly complex, dynamic operating environments in disciplines as diverse as the military, healthcare, and transportation. These complex human machine systems often place additional cognitive and metacognitive demands on the operator. Thus, there is a crucial need to develop training tools for all levels of operators in these dynamic systems. The current study was designed to empirically test the effects of four training methods on performance and mental model accuracy in a microworld simulation game. It was hypothesized that process-focused guidance targeting metacognitive level processes as well as combined …

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An Adhesive Vinyl-Acrylic Electrolyte And Electrode Binder For Lithium Batteries, Binh Tran Jan 2013

An Adhesive Vinyl-Acrylic Electrolyte And Electrode Binder For Lithium Batteries, Binh Tran

Electronic Theses and Dissertations

This dissertation describes a new vinyl-acrylic copolymer that displays great potential for applications in lithium ion batteries by enabling processes that are novel, faster, safer, and less costly than existing manufacturing methods. Overall, the works presented are based on tailored chemical synthesis directly applied to lithium ion battery manufacturing. Current manufacturing methods still have many flaws such as toxic processes and other time consuming if not costly steps. Understanding the chemistry of materials and processes related to battery manufacturing allows the design of techniques and methods that can ultimately improve the performance of existing batteries while reducing the cost. Chapter …

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Non-Degenerate Two Photon Gain In Bulk Gallium Arsenide, Brendan Turnbull Jan 2013

Non-Degenerate Two Photon Gain In Bulk Gallium Arsenide, Brendan Turnbull

Electronic Theses and Dissertations

The purpose of this thesis is to investigate the nonlinear phenomena known as doubly-stimulated, non-degenerate two-photon emission (ND-2PE) in Gallium Arsenide (GaAs). 2PE refers to the simultaneous emission of two-photons as electrons move from the conduction band in a direct gap semiconductor to the valence band. Following the same path for describing one-photon emission (1PE) we describe 2PE as a product of the irradiance, and the negative of the loss which in this case is two-photon absorption, , the negative coming from the population inversion. We attempt to observe 2PE by using a frequency non-degenerate pump-probe experiment in which a …

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Exchange Coupling In Molecular Magnets: Zero, One And Three Dimensions, Asma Amjad Jan 2013

Exchange Coupling In Molecular Magnets: Zero, One And Three Dimensions, Asma Amjad

Electronic Theses and Dissertations

Molecular magnets with different dimensionality, whether they are zero-dimensional singlemolecule magnets (SMM) or one-dimensional single-chain magnets (SCM) are very interesting, since they allow probing the fundamental aspects bordering quantum and classical physics at the nanoscale level. This dissertation covers experimental studies of two Mn-based exchangecoupled molecule-based magnets and two Co-based single-chain magnets, using both dc Halleffect magnetometry and electron paramagnet resonance (EPR) techniques. In these multidimensional systems, the spin of the molecule exhibits quantum mechanical behavior at low temperature. It is quite interesting to observe the effect of magnetic exchange interactions on the magnetic properties of various complexes; hence they …

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Nonparametric And Empirical Bayes Estimation Methods, Rida Benhaddou Jan 2013

Nonparametric And Empirical Bayes Estimation Methods, Rida Benhaddou

Electronic Theses and Dissertations

In the present dissertation, we investigate two different nonparametric models; empirical Bayes model and functional deconvolution model. In the case of the nonparametric empirical Bayes estimation, we carried out a complete minimax study. In particular, we derive minimax lower bounds for the risk of the nonparametric empirical Bayes estimator for a general conditional distribution. This result has never been obtained previously. In order to attain optimal convergence rates, we use a wavelet series based empirical Bayes estimator constructed in Pensky and Alotaibi (2005). We propose an adaptive version of this estimator using Lepski’s method and show that the estimator attains …

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Childhood Predictors In The Severity Of Combat Related Posttraumatic Stress Disorder Among Veterans With Combat Related Exposure, Michael Bermes Jan 2013

Childhood Predictors In The Severity Of Combat Related Posttraumatic Stress Disorder Among Veterans With Combat Related Exposure, Michael Bermes

Electronic Theses and Dissertations

Emerging research suggests that childhood adversities may increase both the risk and symptomology of posttraumatic stress disorder (PTSD) in our veteran population. Over 40% of our reintegrating military veterans return with significant mental health issues led by combatrelated PTSD. PTSD impacts veterans in numerous areas including unemployment, increased criminal justice involvement, increased treatment costs, divorce, co-morbid mental illness, greater levels of domestic violence, homelessness, high college dropout rates, suicide, and long term health problems. The purpose of this study is to investigate the impact of childhood adversities (abuse, neglect, and poverty) upon the severity of combat-related PTSD in veteran populations. …

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The Effect Of A Self-Monitoring Treatment Intervention Package On The Academic Productivity Behavior Of Three High School Students With Autism Spectrum Disorder, Patrick Craanen Jan 2013

The Effect Of A Self-Monitoring Treatment Intervention Package On The Academic Productivity Behavior Of Three High School Students With Autism Spectrum Disorder, Patrick Craanen

Electronic Theses and Dissertations

This study employed a multiple baseline across participants design to investigate the effect of a self-monitoring treatment intervention package (independent variable) consisting of a wristwatch that delivers timed vibrating and digital text prompts, a self-recording form, and a performance graphing worksheet, on the ability of three high school students with Autism Spectrum Disorder to self-monitor the academic productivity component behaviors (dependent variable) of homework assignment completion and submission rates, classroom-based work completion and submission rates, and accuracy and rate of documentation of academic tasks in their student planners. Students earned academic productivity composite scores reflecting the percentage of academic productivity …

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A Study Of Elementary Student Course Completion And Achievement In Virtual And Traditional Format Courses Within The Volusia County School District, Janet Garzia Jan 2013

A Study Of Elementary Student Course Completion And Achievement In Virtual And Traditional Format Courses Within The Volusia County School District, Janet Garzia

Electronic Theses and Dissertations

The focus of this research study was to determine how elementary students enrolled in virtual education classes performed on state assessments and final report card grades in Reading and Mathematics as compared with students enrolled in traditional classes, and to examine whether there was a difference in the successful course completion rates between the two groups. Five research questions guided this study concerning the relationship of successful course completion, final grades, and FCAT 2.0 achievement level scores and the variables of virtual and traditional education in the School District of Volusia County. This study is significant, as the movement of …

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