Digital Commons Network^™

Development Of A Fundamental Autonomous Ground Vehicle Cruise Control Using Matlab And Simulink, Luis F. Martinez

Theses and Dissertations

This study presents and describes the development of a fully autonomous vehicle cruise control system covering the vehicle dynamics and control design needed to simulate such system. It encompasses obstacle avoidance, intelligent-and-optimal lane change as well as adaptive behavior. This study offers a comprehensive two-dimensional cruise control with three degrees of freedom and it is designed using active obstacle avoidance controllers. It also includes optimized fuzzy logic for optimal vehicle trajectory and an extensive array of control law methodology. The end work shows a complete simulation run using MATLAB and Simulink.

Discriminacion A Un Martir: The Ballad Of Felix Longoria, Cristobal A. Carrizales

Theses and Dissertations

This thesis looks at how the Felix Longoria Affair propelled Hector P. Garcia, Lyndon B. Johnson and the American G.I. Forum into the national limelight, while also leaving the Longorias, Three Rivers and Texas in a state of disrepair. The affair in general helped expose injustices that were occurring to Mexicans American in Texas at the time, but left the family, Three Rivers and Texas in a battle over the legacy of how each would be seen in the annals of history.

An Introduction To Serbian Piano Music: Musical And Cultural Influences On Three Selected Composers, Jelena Djukic

Glenn Korff School of Music: Dissertations, Theses, Student Creative Work, and Performances

Serbia is a country that has survived many political and religious conflicts. Perhaps the best way to describe Serbian culture and tradition would be a country whose inhabitants struggled for many years, yet managed to incorporate the best elements of its conquerors’ cultures. Serbian musical identity is an amalgam of local and international influences and styles.

Different foreign authorities occupied this country for centuries. The Danube River was the main border of the Austro-Hungarian Empire, located in the north, and the Turkish Ottoman Empire, situated south of the Danube. The Austro-Hungarian influences on Serbian music are most evident in piano …

Self-Patterning Gd Nano-Fibers In Mg-Gd Alloys, Yangxin Li, Jian Wang, Kaiguo Chen, Meiyue Shao, Yao Shen, Li Jin, Guo-Zhen Zhu

Department of Mechanical and Materials Engineering: Faculty Publications

Manipulating the shape and distribution of strengthening units, e.g. particles, fibers, and precipitates, in a bulk metal, has been a widely applied strategy of tailoring their mechanical properties. Here, we report self-assembled patterns of Gd nano-fibers in Mg-Gd alloys for the purpose of improving their strength and deformability. 1-nm Gd nano-fibers, with a 〈c〉-rod shape, are formed and hexagonally patterned in association with Gd segregations along dislocations that nucleated during hot extrusion. Such Gd-fiber patterns are able to regulate the relative activities of slips and twinning, as a result, overcome the inherent limitations in strength and ductility of Mg alloys. …

Optimization Of Irrigation Decision In Cornsoywater, Dharmic Payyala

School of Computing: Dissertations, Theses, and Student Research

A crop simulation model is used to estimate crop production as a function of weather conditions, soil parameters, and plant related inputs. These crop simulation models are extensively used by farmers, corporations and policy makers for agronomical planning and decision making. CornSoyWater is one such application which provides irrigation recommendation for soy and corn farmers using hybrid maize and soy sim models. As this is a simulation technology, the accuracy of results depends on the quality of data provided to it. One such important input parameter is weather data. CornSoyWater simulates field and crop conditions by retrieving the updated weather …

Characterization Of Molecular Communication Based On Cell Metabolism Through Mutual Information And Flux Balance Analysis, Zahmeeth Sayed Sakkaff

School of Computing: Dissertations, Theses, and Student Research

Synthetic biology is providing novel tools to engineer cells and access the basis of their molecular information processing, including their communication channels based on chemical reactions and molecule exchange. Molecular communication is a discipline in communication engineering that studies these types of communications and ways to exploit them for novel purposes, such as the development of ubiquitous and heterogeneous communication networks to interconnect biological cells with nano and biotechnology-enabled devices, i.e., the Internet of Bio-Nano Things. One major problem in realizing these goals stands in the development of reliable techniques to control the engineered cells and their behavior from the …

Autonomous Uavs For Near Earth Environmental Sensing, David J. Anthony

School of Computing: Dissertations, Theses, and Student Research

Unmanned aerial vehicles (UAVs) are playing an increasing role in large scale environmental monitoring. Small UAVs are increasingly used to monitor agricultural fields, infrastructure projects, and disaster areas. The combination of their sensors, ease of use, and portability make them an ideal tool for collecting information on demand about geographic regions. These small UAVs do have several significant limitations. The UAVs have very limited autonomy and fly pre-determined flight paths far above the underlying terrain, limiting the spatial resolution of the collected data. Current battery technology severely limits their flight times, which in turn limits the temporal resolution of the …

Testing The Independence Hypothesis Of Accepted Mutations For Pairs Of Adjacent Amino Acids In Protein Sequences, Jyotsna Ramanan

School of Computing: Dissertations, Theses, and Student Research

Evolutionary studies usually assume that the genetic mutations are independent of each other. However, that does not imply that the observed mutations are independent of each other because it is possible that when a nucleotide is mutated, then it may be biologically beneficial if an adjacent nucleotide mutates too.

With a number of decoded genes currently available in various genome libraries and online databases, it is now possible to have a large-scale computer-based study to test whether the independence assumption holds for pairs of adjacent amino acids. Hence the independence question also arises for pairs of adjacent amino acids within …

Power Management In Heterogeneous Mapreduce Cluster, Rojee Sunuwar

School of Computing: Dissertations, Theses, and Student Research

The growing expenses of power in data centers as compared to the operation costs has been a concern for the past several decades. It has been predicted that without an intervention, the energy cost will soon outgrow the infrastructure and operation cost. Therefore, it is of great importance to make data center clusters more energy efficient which is critical for avoiding system overheating and failures. In addition, energy inefficiency causes not only the loss of capital but also environmental pollution. Various Power Management(PM) strategies have been developed over the years to make system more energy efficient and to counteract the …

The Effect Of Frequency Resolution On Intelligibility Sentence And Its Relevance To Cochlear Implant Design, Seth H. Roy

School of Computing: Dissertations, Theses, and Student Research

The purpose of this study is to understand how electrical stimulation (as opposed to acoustical stimulation) of the auditory nerve is used in cochlear implants. Speech is a complex signal that changes rapidly in time and frequency domains. Since phonemes (the smallest unit of speech that distinguishes words) depend on nuanced differences in frequency patterns, it would be expected that a signal with drastically reduced frequency information would be of limited value for conveying speech. Such a frequency-poor signal is the object to be investigated in the present work. It is also the basis of the way speech is represented …

Finding Dna Motifs: A Probabilistic Suffix Tree Approach, Abhishek Majumdar

School of Computing: Dissertations, Theses, and Student Research

We address the problem of de novo motif identification. That is, given a set of DNA sequences we try to identify motifs in the dataset without having any prior knowledge about existence of any motifs in the dataset. We propose a method based on Probabilistic Suffix Trees (PSTs) to identify fixed-length motifs from a given set of DNA sequences. Our experiments reveal that our approach successfully discovers true motifs. We compared our method with the popular MEME algorithm, and observed that it detects a larger number of correct and statistically significant motifs than MEME. Our method is highly efficient as …

Towards Building A Review Recommendation System That Trains Novices By Leveraging The Actions Of Experts, Shilpa Khanal

School of Computing: Dissertations, Theses, and Student Research

Online reviews increase consumer visits, increase the time spent on the website, and create a sense of community among the frequent shoppers. Because of the importance of online reviews, online retailers such as Amazon.com and eOpinions provide detailed guidelines for writing reviews. However, though these guidelines provide instructions on how to write reviews, reviewers are not provided instructions for writing product-specific reviews. As a result, poorly-written reviews are abound and a customer may need to scroll through a large number of reviews, which could be up to 6000 pixels down from the top of the page, in order to find …

The Development And Evaluation Of Lecture Tutorials For Introductory Soil Science, Judith K. Turk

Conservation and Survey Division: Faculty and Staff Publications

The wide-array of concepts from the natural sciences that must be mastered to succeed in an introductory soil science course presents a significant challenge to students. This study was conducted to determine if students’ conceptual development regarding topics in introductory soil science could be improved by using lecture tutorials. Lecture tutorials are activities that students complete following a lecture. They guide the students to critically analyze their understanding of a concept presented in the lecture. Eight lecture tutorials were written and evaluated using pre/post quizzes and surveys in two courses (an environmental science program course and a general studies course). …

A Further Analysis Of Commission Errors During Discrete Trial Training, Tavy Alisa Matthews

Theses and Dissertations

Treatment integrity has been manipulated in various ways to evaluate its impact on intervention effectiveness. Studies have compared different types of integrity failures and levels of treatment integrity in various contexts and behavioral interventions. Evaluations include differential reinforcement of alternative behavior, child compliance, and discrete trial training. However, further research is needed to establish the point at which integrity becomes detrimental to intervention effectiveness. The purpose of this study was to conduct a parametric analysis (i.e., 100%, 75%, 50%, & 25%) of treatment integrity to examine the effects of commission errors during discrete trial training. Three participants, ages 35 - …

Predictors Of Diarrheal Mortality And Patterns Of Caregiver Health Seeking Behavior In In Karachi, Pakistan, Farah Naz Qamar, Umber Zaman, Farheen Quadri, Asia Khan, Babar Tasneem Shaikh, Iqbal Azam, Dilruba Nasrin, Karen Kotloff, Myron Levine, Nick Brown

Department of Paediatrics and Child Health

Background: Pakistan is unfortunately among the five countries that contributed to the most deaths due to diarrhea and pneumonia in 2010. To explore factors associated with diarrheal deaths we assessed care-seeking behavior and other predictors of diarrhea-related mortality in children in selected low-income peri-urban communities of Karachi, Pakistan.
Methods: A mixed methods study (qualitative and quantitative) using matched case-control design and focus group discussions with parents of children with moderate to severe diarrhea (MSD) was undertaken. Cases were children Demographic, clinical, and care-related behavioral predictors of mortality were assessed. Conditional logistic regression was performed, matched adjusted odds ratios (mOR) are …

Depletion Today Keeps The Apple Away: Effects Of Workplace Resource Processes On Daily Health Behavior And Recovery, Chelsea Alyce Lenoble

Theses and Dissertations

The workplace has become an increasingly demanding environment in which individuals must expend personal resources in order to meet job demands (Hobfoll, 1989). Without ample opportunity to recover these depleted resources, employees risk physical and psychological strains (Meijman & Mulder, 1998). It was proposed that depletion and recovery that occurs throughout the workday would impact recovery activities outside of work. Further, two new constructs were examined as moderators of the proposed relationships: personal energy recovery climate (PERC) and non-work recovery interferences (NWRI). A two-week daily diary study was conducted, with 145 working adults completing four surveys throughout each workday. Resource …

Evaluating Computerized Math Performance Using Progressive Ratio Schedules In Children With Attention Deficit Hyperactivity Disorder, Lauren Stroker

Theses and Dissertations

One method of assessing reinforcer strength is to use a progressive ratio (PR) schedule of reinforcement, whereby response requirements to access reinforcers gradually increase. PR schedules have been used to assess reinforcer potency in numerous applications with nonhumans in basic research, children and adults with disabilities, and individuals with histories of substance abuse problems. However, the utility of PR schedules to determine robust reinforcers has not been assessed with children with attention deficit – hyperactivity disorder (ADHD) regarding academic tasks, such as mathematics. The inability to remain on task presents a challenge for teachers in schools, and poses detrimental effects …

Development Of Fault Tolerant Adaptive Control Laws For Aerospace Systems, Andres E. Perez Rocha

Doctoral Dissertations and Master's Theses

The main topic of this dissertation is the design, development and implementation of intelligent adaptive control techniques designed to maintain healthy performance of aerospace systems subjected to malfunctions, external parameter changes and/or unmodeled dynamics. The dissertation is focused on the development of novel adaptive control configurations that rely on non-linear functions that appear in the immune system of living organisms as main source of adaptation. One of the main goals of this dissertation is to demonstrate that these novel adaptive control architectures are able to improve overall performance and protect the system while reducing control effort and maintaining adequate operation …

Coupled Fluid-Structure Interaction Modeling Of A Parafoil, Brandon Burnett

Doctoral Dissertations and Master's Theses

In the summer of 2014, Performance Designs, Inc. contacted Embry-Riddle Aeronautical University’s Eagle Flight Research Center to lead an investigation on square parachute design and optimization using modern computational methods to reduce costs in experimental testing. This thesis investigates the foundation for using an implicit fluid-structure interaction computational model to tackle the challenges of modeling a highly-flexible, porous fabric for design optimization of a parafoil parachute’s transient performance. Canopy deformations of a single-cell square parafoil using a fluid-structure interaction (FSI) model with nonlinear material modeling is compared to an experimental setup of matching geometry. The results of this thesis yielded …

Effect Of Slot Span On Wing Performance, Juan F. Granizo

Doctoral Dissertations and Master's Theses

This report presents new numerically-derived correlations to estimate the aerodynamic properties of a three-dimensional wing that features a partial to full span fixed slot. Fixed slots have been thoroughly studied in the past with regards to their operation and the relation between slot geometry and wing performance. There have also been many studies on the advantages and disadvantages of tip-slotted wings and the comparison between these and full-slotted wings. Up to this point however, a study on the effects of slot span on wing performance has not been performed. Effect of slot span on wing performance is evaluated in an …

Model Predictive Control Of A Nonlinear Aeroelastic System Using Volterra Series Representations, Wai Leuk Law

Doctoral Dissertations and Master's Theses

The purpose of this study is to investigate the potential effectiveness of using a Volterra-based Model Predictive Control strategy to control a nonlinear aeroelastic system. Model Predictive Control (MPC), also known as Receding Horizon Control (RHC), entails computing optimal control inputs over a finite time horizon, applying a portion of the computed optimal control sequence, and then repeating the process over the next time horizon. The Volterra series provides input-output models of a dynamical system in terms of a series of integral operators of increasing order, where the first-order Volterra operator models the linear dynamics and the higher-order operators model …

Effect Of Flow-Acoustic Resonant Interactions On Aerodynamic Response Of Transitional Airfoils, Joseph Hayden

Doctoral Dissertations and Master's Theses

A high-accuracy numerical study is conducted to examine the impact of flow-acoustic resonant interactions on the aerodynamic response of symmetric and cambered airfoils in the realistic transitional flow regimes with Rec=140,000 and M=0.0465 as well as the low Reynolds number flow regime with Rec=10,000 and M=0.2. The symmetric NACA-0012 and the cambered SD7003 airfoils are investigated at various angles of attack that have been found previously to include both the tone and no-tone producing regimes, with specific focus on the aerodynamic lift response. Additional simulations are conducted with a low-intensity synthetic turbulence introduced upstream of the airfoils in order to …

Windshield Defrost And Deice Using Carbon Nanotube Composite, Santhosh Kumar Loganathan

Doctoral Dissertations and Master's Theses

Carbon nanotubes (CNT) are well known for their high thermal and electrical conductivities and can offer a great advantage by converting the applied electrical energy into instant heat with minimum energy loss. The goal of this research is to develop a very thin CNT layer sandwiched between two layers of glass substrate in order to generate instant heat through electrodes. The thin CNT layer is fabricated using the CNTRENETM solution, which is a mixture of single-walled nanotubes (SWNTs) (~75%), double-walled nanotubes (DWNTs), and multi-walled nanotubes (MWNTs) with an average CNT length of ~0.4 - 0.6 μm. The thin layer is …

A Detailed Uncertainty Analysis Of Heat Transfer Experiments Using Temperature Sensitive Paint, Anish Prasad

Doctoral Dissertations and Master's Theses

Heat transfer experiments for different cooling techniques for a gas turbine blade are performed and the data are collected via temperature sensitive paint, ammeter, thermocouple and manometer measurement techniques. These data are subjected to uncertainty analysis and the major contributing parameter in the uncertainty is found. A tool to identify the major contributing parameter is devised to reduce the uncertainty in the experiment. Further the effect of temperature difference (surface temperature to bulk temperature) is studied to determine the impact on uncertainty and to determine its importance. The analysis between various implementations of the student’s t distribution are conducted to …

Smart Rock Technology For Real-Time Monitoring Of Bridge Scour And Riprap Effectiveness -- Design Guidelines And Visualization Tools, Genda Chen, Yan Tang, Yizheng Chen, Zhaochao Li, Chuanrui Guo, Liang Fan, Yi Bao, Xiuyan Hu, Matthew Klegseth

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims to further develop and demonstrate the recently-proposed smart rock technology for scour depth and protection effectiveness monitoring. A smart rock is one or two stacked magnets encased in a concrete sphere with a specially-designed rotational mechanism. Design guidelines, rotational mechanisms, remote measurement tools and localization algorithms of smart rocks were developed and validated at three bridge sites. The effect of steel reinforcement in bridge piers/deck on the orientation of gravity-controlled magnets was negligible. The localization accuracy with a single smart rock met a general requirement of less than 0.5 m in engineering applications. The spherical smart rock …

The Role Of Leed Certification In Consumer Major Purchase Decisions: A Case Study Of The Chattanooga Volkswagen Manufacturing Facility, Amy E. Katcher-Dunne

Masters Theses and Doctoral Dissertations

The Leadership in Energy and Environmental Design (LEED) certification program serves as a benchmark for ‘green’ construction in the U.S. Although considerable research has investigated the marketability of LEED-certified buildings, no direct attention has been given to assessing if the benefits of LEED certification filter down to the profitability of products manufactured in those buildings. To investigate this potential influence, I conducted a large-scale survey of regional owners of the Volkswagen Passat, which is manufactured in the world's first automobile plant to achieve LEED Platinum status. Results suggest that manufacturing facility LEED certification does not influence product purchasing decisions regardless …

Verbal Morphology And Grammatical Aspect In Sarikoli, Timothy S. Palmer

Theses and Dissertations

Grammatical aspect in Sarikoli, an Eastern Iranian (Pamir) language, has never been adequately described. This work fills a gap in the descriptive literature, beginning with a straightforward restatement of verbal morphosyntax, and moving to a discussion of verb stems and their uses. Verb stems in Sarikoli include the infinitive, imperfective, perfective, and perfect. Additional morphemes discussed in this work include the durative clitic, stative (resultative) suffix, cessative suffix, and agreement suffixes and clitics.

Sarikoli verbal morphology encodes aspect, not tense. The major grammatical aspects of Sarikoli include perfective, imperfective, perfect, and durative. Verb stems and other aspectual marking in context …

The East Texan, 2016-12-01, Texas A&M University-Commerce

All Issues

A color copy of The East Texan, a student newspaper published at Texas A&M University-Commerce.

Nondestructive Evaluation Of Steel Bridges: Methods And Applications, Theodore Hopwood Ii, Christopher Goff, Jared Fairchild, Sudhir Palle

Kentucky Transportation Center Research Report

Nondestructive evaluation (NDE) methods can be used to assess in-service steel bridges for problematic conditions caused by factors such as design, manufacturing, fabrication, and the service effects of traffic and corrosion. This report discusses typical NDE test methods used on bridges, including penetrant testing, magnetic particle testing, eddy current testing, ultrasonic testing (including phased array testing), radiography, and acoustic emission testing. NDE operations such as flaw location, characterization, and sizing are covered as well. Results of a national survey of departments of transportation’s (DOTs) use of NDE are presented. A simple procedure for using NDE to address DOT bridge concerns …

Reliable Hardware Architectures For Cyrtographic Block Ciphers Led And Hight, Srivatsan Subramanian

Theses

Cryptographic architectures provide different security properties to sensitive usage models. However, unless reliability of architectures is guaranteed, such security properties can be undermined through natural or malicious faults. In this thesis, two underlying block ciphers which can be used in authenticated encryption algorithms are considered, i.e., LED and HIGHT block ciphers. The former is of the Advanced Encryption Standard (AES) type and has been considered areaefficient, while the latter constitutes a Feistel network structure and is suitable for low-complexity and low-power embedded security applications. In this thesis, we propose efficient error detection architectures including variants of recomputing with encoded operands …