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Computational Design Of Staged Pressurized Oxy-Coal Combustion, Gideon Ozioma Udochukwu Jan 2019

Computational Design Of Staged Pressurized Oxy-Coal Combustion, Gideon Ozioma Udochukwu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Staged pressurized oxy-coal combustion (SPOC) is nowadays a promising technology to be used for low-cost, low-emission, high-efficiency power generation. The objective of this thesis is to compliment the experiments ongoing at the Washington University, St. Louis (WUSTL) by means of numerical simulations, thereby providing better understanding of the fluid flow, turbulence, combustion characteristics, particle dynamics and heat transfer. Carbon dioxide (CO2) is injected alongside the coal, for its carriage. A small amount of methane (CH4) is also injected alongside the coal to maintain a steady flame. The simulations are performed for a 3D geometry with the following energy source distribution: …


Assessing The Reliability Of Physical End Matching And Chemical Comparison Of Pressure Sensitive Tapes, Meghan Nicole Prusinowski Jan 2019

Assessing The Reliability Of Physical End Matching And Chemical Comparison Of Pressure Sensitive Tapes, Meghan Nicole Prusinowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pressure sensitive tapes are a common evidence type in a variety of forensic cases, including violent crimes, drug trafficking, and terrorism. Forensic laboratories are often requested to analyze tape samples for composition and potential source identification. Tape samples manufactured from different sources are often distinguishable when using a combination of sensitive analytical techniques. Nonetheless, the interpretation of the data remains challenging due to a lack of standard criteria and guidelines from which examiners can support their conclusions. As a result, there is a need to standardize the protocols of interpretation of physical and chemical comparisons of tape evidence.

The manufacture …


Identification Of Burnt Smokeless Gunpowders Through Physical Characteristics, Cameron Taylor Hartwig Jan 2019

Identification Of Burnt Smokeless Gunpowders Through Physical Characteristics, Cameron Taylor Hartwig

Graduate Theses, Dissertations, and Problem Reports (ETD)

Firearms are one of the most commonly used weapons by violent criminals throughout the United States. In crimes involving the discharge of a firearm, residues from the combustion products are deposited on the shooter and in the firing direction. Some of the residues left behind are unburnt and partially burnt particles of the propellant. The most common propellant used in modern firearms is smokeless powder. The identification of particles as smokeless powder and the determination of the brand of the powder are two ways a forensic examiner may be able to utilize smokeless powder evidence. The determination of the brand …


Stories Of Deindustrialization: Exploring Narratives In Weirton, West Virginia, Ella Jennings Jan 2019

Stories Of Deindustrialization: Exploring Narratives In Weirton, West Virginia, Ella Jennings

Graduate Theses, Dissertations, and Problem Reports (ETD)

Since the 1960s, cities throughout the world have confronted the phenomenon of deindustrialization, wherein economies advance and transition into a post-industrial environment. This evolution leads to complications on political, social, and economic scales, as localities struggle to find a path to the future that can guarantee the job security and community identity once offered by industry. Weirton, West Virginia, is one such place. The city, once home to Weirton Steel Corporation, a powerhouse steelmaker that employed 13,000 people, fell victim to the fall of the United States’ steel industry, and now is a shadow of its former self. This project …


New Method Of Manufacturing Carbon Foam, Matthew D. Artimez Jan 2019

New Method Of Manufacturing Carbon Foam, Matthew D. Artimez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Carbon foam is a product that has some unique features. Carbon foam is a light weight material that has a high crush strength. It is electrically conductive, but because it is composed of air space between the tendrils, it is not a thermal conductor. Since it contains no volatile content, it is noncombustible. All these features allow carbon foam to have many modern applications. Currently, there are only three methods of producing carbon foam, and all three are not cost- efficient enough to meet the demand of potential new markets.

In this thesis, a new procedure of producing carbon foam …


Implications Of Sampling Methods On Geospatial Mapping Of Methane Sources, Dakota Wesley Oliver Jan 2019

Implications Of Sampling Methods On Geospatial Mapping Of Methane Sources, Dakota Wesley Oliver

Graduate Theses, Dissertations, and Problem Reports (ETD)

Natural gas is deployed as an alternative fuel due to its cost and post-combustion emissions. However, methane, the main component of natural gas, is a greenhouse gas with a global warming potential (GWP) of at least 28 over 100 years. Currently, natural gas and petroleum systems are the highest emitters of methane to the atmosphere. Using conventional methods, the detection of natural gas leaks is time consuming. Currently, natural gas production sites deploy the Environmental Protection Agency’s (EPA) Method 21 or optical gas imaging (OGI) for methane leak detection. Both methods require access to the natural gas site along with …


Development Of A Dynamic Model And Control System For Load-Following Operation Of Supercritical Pulverized Coal Power Plants, Parikshit S. Sarda Jan 2019

Development Of A Dynamic Model And Control System For Load-Following Operation Of Supercritical Pulverized Coal Power Plants, Parikshit S. Sarda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thermal power plants that have been designed to operate at their rated capacity are being forced to cycle their load and operate under low-load condition to meet changing load demands due to the increased penetration of renewables into the electric grid. The rapid load-following operation is leading to challenging control problems. The goal of this research is to develop dynamic model and control system for efficient load-following operation. The focus of this work is on supercritical pulverized coal (SCPC) power plants. The steady-state model is developed using Aspen Plus and Aspen Custom Modeler and then converted to a pressure-driven Aspen …


In Situ Measurement Of Fatigue Induced Crack Growth In Inconel 718 Using Direct Current Potential Drop Method, Joel C. Lindsay Jan 2019

In Situ Measurement Of Fatigue Induced Crack Growth In Inconel 718 Using Direct Current Potential Drop Method, Joel C. Lindsay

Graduate Theses, Dissertations, and Problem Reports (ETD)

With recent advances in air breathable engines comes more extreme temperature environments that engine components must tolerate. During the design of these engines, it is necessary to understand how material fatigue failures occur at these new, higher operating temperatures. In providing understanding, the following fundamental study focuses on the statistical nature of crack jumps (changes in crack length over time) during fatigue in a polycrystalline nickel-based superalloy, Inconel 718 (IN718). In situ measurement of the crack length at several loading conditions were conducted using a direct current potential drop (DCPD) measurement method. Experimental data was collected at six different fatigue …


Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen Jan 2019

Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …


The Relationship Between Social Skills And Problem Behaviors In Adolescent Males With Autism Spectrum Disorders, Amanda Armstrong Randall Jan 2019

The Relationship Between Social Skills And Problem Behaviors In Adolescent Males With Autism Spectrum Disorders, Amanda Armstrong Randall

Graduate Theses, Dissertations, and Problem Reports (ETD)

Adolescent males with autism spectrum disorder commonly display an increased prevalence of problem behaviors and persistent deficits in social skills when compared to their typically developing peers. The present study deployed a single subject, multiple-baseline design to investigate the use of the social skills training program Super Skills: A Social Skills Group Program for Children with Asperger Syndrome, High-Functioning Autism and Related Challengesto promote enhanced social skills and minimize problem behaviors. Two groups of adolescent males with autism (N = 6) participated in weekly social skills training groups also containing typically developing peers (N = 3) once …


Cognitive And Affective Influences On Decision-Making Strategies And Outcomes, Michaela S. Reardon Jan 2019

Cognitive And Affective Influences On Decision-Making Strategies And Outcomes, Michaela S. Reardon

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examines how factors such as emotion and planning abilities, determine decision-making strategies and outcomes. Consumer-based decision tasks are one way for researchers to measure the decision-making process and outcomes of individuals, while bringing an element of reality to the task through the utilization of decisions about everyday items that someone might purchase (e.g., a car, apartment, etc.). Using these types of tasks, researchers can measure the quality of a decision (e.g., did the participant come up with the best solution?), as well as the decision or search strategy. Previous research shows that cognitive factors are important when individuals …


The Inclusion Of Organ Within The Concert Band Instrumentation With An Annotated Listing Of Original Works For Concert Band And Organ, Matthew Justin Mccurry Jan 2019

The Inclusion Of Organ Within The Concert Band Instrumentation With An Annotated Listing Of Original Works For Concert Band And Organ, Matthew Justin Mccurry

Graduate Theses, Dissertations, and Problem Reports (ETD)

There is a very limited amount of information regarding musical works available for concert band and organ. When used in conjunction with the concert band, the organ can serve different roles such as soloist with concert band accompaniment, a complimentary texture within the concert band sound, or the means for creating a majestic impact point or grand finale with full forces of organ and concert band combined. Although there are only a small number of works that fall into this category, composers continue to write works for concert band that include organ in the instrumentation. This document is an attempt …


Automatic Detection Of Insecure Codes In Stack Overflow, Shifu Hou Jan 2019

Automatic Detection Of Insecure Codes In Stack Overflow, Shifu Hou

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the popularity of modern social coding paradigm such as Stack Overflow grows, its potential security risks increase as well (e.g., insecure codes could be easily embedded and distributed). To address this largely overlooked issue, we bring a new insight to exploit social coding properties in addition to code content for automatic detection of insecure code snippets in Stack Overflow. To determine if the given code snippets are insecure, we not only analyze the code content, but also utilize various kinds of relations among users, badges, questions, answers, code snippets and keywords in Stack Overflow. To model the rich semantic …


Stockmanship Education And Evaluation, John K. Yost Jan 2019

Stockmanship Education And Evaluation, John K. Yost

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation documents two separate works. The first is an evaluation of WVU SFMS/SOIDC Large Animal Module and the second is the development and use of the Stockman’s Scorecard. The WVU SFMS/SOIDC Large Animal Module provides foundational information on food animal husbandry and veterinary procedures to SOF Combat Medic candidates. A quasi-experimental design was used to determine if the module content resulted in an increase in food animal production knowledge for the participants. Seventy-five percent of the subjects had no previous livestock exposure and only seven percent had previously participated in 4-H or FFA. Matched pair analysis determined that the …


Immunity-Based Framework For Autonomous Flight In Gps-Challenged Environment, Mohanad Al Nuaimi Jan 2019

Immunity-Based Framework For Autonomous Flight In Gps-Challenged Environment, Mohanad Al Nuaimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the artificial immune system (AIS) paradigm is used for the development of a conceptual framework for autonomous flight when vehicle position and velocity are not available from direct sources such as the global navigation satellite systems or external landmarks and systems. The AIS is expected to provide corrections of velocity and position estimations that are only based on the outputs of onboard inertial measurement units (IMU). The AIS comprises sets of artificial memory cells that simulate the function of memory T- and B-cells in the biological immune system of vertebrates. The innate immune system uses information about …


Henosis Experience In Gaming: A Metric For Adjustments To Global Schema And Appraised Meaning, Evan Robert Watts Jan 2019

Henosis Experience In Gaming: A Metric For Adjustments To Global Schema And Appraised Meaning, Evan Robert Watts

Graduate Theses, Dissertations, and Problem Reports (ETD)

Meaningfulness is a media gratification distinct from enjoyment characterized by feelings of insight, contemplation, and poignancy. Video games, too, can elicit experiences of meaningfulness, but the mechanisms underlying meaningfulness are unclear and in need of further exploration. Adapting work from existential psychology, this research proposes the construct of henosis as one mechanism that might contribute to meaningful video game experiences. Henosis is a response to experiences in which a person’s fundamental schema about the world (global schema) is challenged by an event which contradicts this schema. Henosis describes the process by which this discrepancy is resolved via either reappraising the …


Efficacy Of Cognitive Training Intervention With A Coaching Component On Attention And Response Control In Emerging Adults, Thomas Craig Foster Jr Jan 2019

Efficacy Of Cognitive Training Intervention With A Coaching Component On Attention And Response Control In Emerging Adults, Thomas Craig Foster Jr

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cognitive training, a nonpharmacological intervention for attention and learning-related difficulties, is a promising treatment option for emerging adults. The aim of this study was to explore the efficacy of a cognitive training program with a coaching component on measures of attention and response control in university students. Between 2014 and 2017, 39 students with reported attention concerns engaged in a cognitive training program over ten weeks (20 sessions) at a university counseling center. Differences in participants’ attention and response control as measured by the IVA-2 Continuous Performance Test (CPT) were evaluated before and after the intervention. Demographic data, including clinician …


Untangling The Reciprocal Relation Of The Behavioral And Physiological Immune Systems, Baris Sevi Jan 2019

Untangling The Reciprocal Relation Of The Behavioral And Physiological Immune Systems, Baris Sevi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the past decade, there has been an exponential increase in the study of the Behavioral Immune System (BIS), a suite of psychological processes that serves an infectious disease avoidance function. The BIS is proposed to be inherently intertwined with the physiological immune system. However, very few studies have actually demonstrated this fundamental, theoretical assumption. The purpose of this thesis was to test the possible relation between the physiological and behavioral immune systems in two studies. In Study 1 (N = 388), the relation between implied activation of the physiological immune system and BIS sensitivity was examined. Participants who reported …


Resurgence Of Academic Responses, Catherine Louise Stephens Jan 2019

Resurgence Of Academic Responses, Catherine Louise Stephens

Graduate Theses, Dissertations, and Problem Reports (ETD)

Resurgence is the recurrence of a previously reinforced response after a more recently reinforced response is placed on extinction. Resurgence may explain the recurrence of socially appropriate behavior, including academic responding, but this had not yet been empirically demonstrated. The aim of this study was to determine if resurgence would occur when a participant solved quadratic equations using multiple methods. Each participant was taught two methods of solving quadratic equations across experimental phases, followed by a phase in which neither method resulted in the correct solution. In the first phase, only simple factoring was reinforced. In the second phase, only …


Investigation Of Various Factors Affecting Quantification And Characterization Accuracy Of Nox Measurement At Near Zero Level In A Cvs Sampling Set-Up, Samuel Abimbola Ogunfuye Jan 2019

Investigation Of Various Factors Affecting Quantification And Characterization Accuracy Of Nox Measurement At Near Zero Level In A Cvs Sampling Set-Up, Samuel Abimbola Ogunfuye

Graduate Theses, Dissertations, and Problem Reports (ETD)

Accurate measurement of oxides of nitrogen (NOx) concentrations at near-zero levels using the constant volume sampling (CVS) system is a critical consideration in emissions quantification for engine and vehicle research and certification purposes. Various technological efforts and research are being implemented to ensure emissions from automobile and on-road transportation sources tend towards lower concentrations. This development has resulted in NOx concentration measurements to shift towards near-zero and thus, reach the detection limits of traditional measurement approaches and methods. There are several factors that might deter achieving measurement accuracy at this level, as their effect becomes significant at low NOx concentrations. …


Propagation And Morphology Of Premixed Flames In Obstructed Channels Under Atmospheric And Supercritical Conditions, Abdulafeez Akinola Adebiyi Jan 2019

Propagation And Morphology Of Premixed Flames In Obstructed Channels Under Atmospheric And Supercritical Conditions, Abdulafeez Akinola Adebiyi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The understanding of the morphology and propagation of premixed flames in channels is vital for the design and development of efficient propulsion systems requiring high heat release, such as pulse detonation engines, and for resolving accidental fire in industrial conduits. In this work, extensive computational simulation of premixed flames in channels (with rectangular and cylindrical cross sections) with closely packed obstacles are carried out with the goal of providing insights into flame propagation under various conditions which would be invaluable to the development and safety of energy and propulsion systems as well as for the mitigation of accidental fires in …


Sodium Channel Distribution In The Apical Dendrites Of Pyramidal Cells Vary In The Hindbrain Of Apteronotus Leptorhynchus., Sree Indrani Motipally Jan 2019

Sodium Channel Distribution In The Apical Dendrites Of Pyramidal Cells Vary In The Hindbrain Of Apteronotus Leptorhynchus., Sree Indrani Motipally

Graduate Theses, Dissertations, and Problem Reports (ETD)

Apteronotid weakly electric fish heavily rely on their electrosensory system for behaviors like spatial navigation, communication and prey capture. Since the behaviorally important information about their environment is contained in the spatial and temporal modulations of the electrosensory signal, efficient mechanisms to process this information with great fidelity are of the utmost importance. Efficient sensory processing often involves having multiple parallel processing streams so that each stream can specialize to treat signals with different properties. This strategy requires the response properties and neural dynamic to be adjusted in each pathway to implement different neural coding strategies. One of the neural …


Evaluating The Approach Of Using Nox Control Performance Tracking For On-Board Diagnostics Of Heavy-Duty Diesel Vehicles, Renata Castiglioni Jan 2019

Evaluating The Approach Of Using Nox Control Performance Tracking For On-Board Diagnostics Of Heavy-Duty Diesel Vehicles, Renata Castiglioni

Graduate Theses, Dissertations, and Problem Reports (ETD)

egulatory agencies have taken several measures to ensure proper regulation of engine exhaust in response to a yearly rise in urban pollution levels. This is due in no small part to vehicular traffic and resulting air pollution from exhaust.

This study evaluates the NOx Control Performance Tracking (NCPT) Onboard Diagnostic (OBD) parameter proposed by the California Air Resources Board (CARB) as a tool to assess in-use heavy-duty vehicle performance. It also assesses the various criteria prescribed in the NCPT approach for applicability to real-world vehicle data.

In order to analyze the data, the study also investigated the effect of various …


Elucidating A Common Mechanism Of Proteasome Impairment In Neurodegenerative Disease And Its Pharmacological Intervention, Tiffany Ann Thibaudeau Jan 2019

Elucidating A Common Mechanism Of Proteasome Impairment In Neurodegenerative Disease And Its Pharmacological Intervention, Tiffany Ann Thibaudeau

Graduate Theses, Dissertations, and Problem Reports (ETD)

Proteostasis is maintained by several systems in the cell including the ubiquitin-proteasome system (UPS), chaperones, chaperone-mediated autophagy, and macroautophagy. The UPS is the principle route for the degradation of intracellular misfolded, damaged, or unneeded cellular proteins and has a critical role essential every cell process, including: cell cycle progression, transcriptional regulation, genome integrity, apoptosis, immune responses, and neuronal plasticity. When the efficiency of protein degradation is perturbed, misfolded and damaged protein aggregates can accumulate to toxic levels and cause neuronal dysfunction, which may underlie many neurodegenerative diseases. It is widely appreciated that soluble oligomers of misfolded proteins (e.g. Aβ, Alzheimer’s; …


Design And Implementation Of An Instantaneous Fuel Mass Flow Measurement System For Use In Verification Of Locomotive Emissions, Adam Wayne James Jan 2019

Design And Implementation Of An Instantaneous Fuel Mass Flow Measurement System For Use In Verification Of Locomotive Emissions, Adam Wayne James

Graduate Theses, Dissertations, and Problem Reports (ETD)

Located in Altoona, PA, the Juniata Thoroughbred Emissions Research lab has provided emissions testing and research for several locomotive companies such as CSX, Electro Motive Diesel (EMD), and General Electric (GE). The emissions laboratory measures locomotive emissions through partial flow dilution (PFD) sampling for particulate matter (PM) using a Sierra Instruments BG3 and measures raw gaseous emissions using a MEXA 7100D gaseous emission analyzer. Fuel consumption is measured on a gravimetric basis and is used in verification of proportional sampling of exhaust flow. There were two research goals for this study which were (1) verify that the emissions measurement system …


Genetic Regulation Of The Elicitation Of Glyceollin Biosynthesis In Soybean, Md. Asraful Jahan Jan 2019

Genetic Regulation Of The Elicitation Of Glyceollin Biosynthesis In Soybean, Md. Asraful Jahan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glyceollin phytoalexins are the pathogen-elicited defense metabolites that belong to the isoflavonoid family of molecules of soybean (Glycine max L. Merr). Phytophthora root and stem rot of soybean caused by Phytophthora sojae is a destructive disease throughout the soybean-growing regions worldwide causing devastating economic damages (globally $1-2 billion and over $250 million in the USA) every year. Engineering soybean plants that produce higher levels of glyceollins could confer resistance against this pathogen. Glyceollins also show anticancer and neuroprotective activities in mammals, therefore they are important for agriculture and medical research. Firstly, we were interested in understanding how biotic and …


Analysis Of Unconventional Oil And Gas Impacts On Downstream Fish Assemblages And Physiological Stress, Joshua Noah Ankeny Jan 2019

Analysis Of Unconventional Oil And Gas Impacts On Downstream Fish Assemblages And Physiological Stress, Joshua Noah Ankeny

Graduate Theses, Dissertations, and Problem Reports (ETD)

Unconventional Oil and Gas (UOG) production has been steadily expanding throughout the mid-Atlantic since 2008. Increased sedimentation, degraded water chemistry and an overall decrease in habitat quality due to UOG is anticipated to negatively impact aquatic inhabitants, a common observation in other stressed landscapes (i.e., mining, agriculture, development). We assessed stream health through both community analysis and physiological parameters (i.e., growth and hematocrit). A before-after-control-impact study uncovered three fish metrics that were significantly different following UOG disturbances. The invertivore-piscivore metric decreased following UOG disturbance (p = 0.045) whereas two benthic metrics saw a surprising increase (p = 0.003 and p …


The Effect Of Phonetic Training On The Perception And The Production Of L1-Related Difficult Sounds In Esl, Moonjung Jang Jan 2019

The Effect Of Phonetic Training On The Perception And The Production Of L1-Related Difficult Sounds In Esl, Moonjung Jang

Graduate Theses, Dissertations, and Problem Reports (ETD)

A considerable amount of research has been conducted on the influence of first languages’ phonological features in pronunciation of a second language. While it has been accepted that pronunciation is one of the most significant aspects in the acquisition of a second language, many studies have not considered whether explicit phonetic training in pronunciation would help English as Second language Learners to improve their pronunciation on particular English sounds that can be confused due to L1 influence. The present study will explore whether Korean ESL learners are able to perceive the particular pairs of the different phonetic sounds (i.e., /p/-/f/, …


Pharmaceutical Scheduling Using Simulated Annealing And Steepest Descent Method, Bryant Jamison Spencer Jan 2019

Pharmaceutical Scheduling Using Simulated Annealing And Steepest Descent Method, Bryant Jamison Spencer

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the pharmaceutical manufacturing world, a deadline could be the difference between losing a multimillion-dollar contract or extending it. This, among many other reasons, is why good scheduling methods are vital. This problem report addresses Flexible Flowshop (FF) scheduling using Simulated Annealing (SA) in conjunction with the Steepest Descent heuristic (SD).

FF is a generalized version of the flowshop problem, where each product goes through S number of stages, where each stage has M number of machines. As opposed to a normal flowshop problem, all ‘jobs’ do not have to flow in the same sequence from stage to stage. The …


A Preliminary Investigation Of Velopharyngeal Timing In Normally Developing Preschool Children And Those With Speech Sound Disorders, Taylor Danielle Snodgrass Jan 2019

A Preliminary Investigation Of Velopharyngeal Timing In Normally Developing Preschool Children And Those With Speech Sound Disorders, Taylor Danielle Snodgrass

Graduate Theses, Dissertations, and Problem Reports (ETD)

As children acquire speech and language, they also begin to develop speech motor control. A widely accepted theoretical model for explaining speech acquisition and motor modifications necessary for appropriate speech is the Directions Into Velocities of Articulators (DIVA)model.This model posits that individuals plan and produce speech (feedforward system). If errors in speech are identified, they are modified since the DIVA Model includes a feedback system that is sensitive to such perturbations made during speech production (feedback system). This feedback system functions to make positive changes to one’s motor programming for speech. Literature suggests that children gain stability …