Engineering Commons^™

Unmanned Ground Vehicle System To Collect Soil Moisture Data, Austin Edward Flynt

Theses and Dissertations

With an increased interest in precision agriculture, it is important to identify efficient ways to monitor soil moisture. Soil moisture can be monitored using handheld sensors, but this method is laborious and time consuming. Remote methods, such as radar systems can be used as well, but these methods require ground truth data to verify their accuracy. It becomes clear that to collect this data regularly and reliably, a mobile robotic device is necessary. This thesis proposes to implement mobile robot take soil moisture measurements with less human effort than existing methods while maintaining the same accuracy. This soil moisture data …

A Dual Perspective Towards Building Resilience In Manufacturing Organizations, Steven A. Fazio

Theses and Dissertations

Modern manufacturing organizations exist in the most complex and competitive environment the world has ever known. This environment consists of demanding customers, enabling, but resource intensive Industry 4.0 technology, dynamic regulations, geopolitical perturbations, and innovative, ever-expanding global competition. Successful manufacturing organizations must excel in this environment while facing emergent disruptions generated as biproducts of complex man-made and natural systems. The research presented in this thesis provides a novel two-sided approach to the creation of resilience in the modern manufacturing organization. First, the systems engineering method is demonstrated as the qualitative framework for building literature-derived organizational resilience factors into organizational structures …

Hydrology And Water Quality Analysis In The Big Black River Watershed, Mississippi, Moniba Shabbir

Theses and Dissertations

Evaluating hydrology and water quality for the Big Black River Watershed in Mississippi was accomplished by using the Better Assessment Science Integrating Point and Nonpoint Source (BASINS 4.5), Loading Simulation Program in C++ (LSPC), and Water Quality Analysis Simulation Program (WASP) models. The watershed model calibration was originally accomplished by using historical data collected from U.S. Geological Survey (USGS). The watershed model was calibrated using data from 2000 through 2018 in order to quantify stream flow and point source discharges under a variety of hydrologic conditions. The model predicted response of hydrology was consistent with the observed data range. The …

Leveraging Choice Modeling Technique For Enhancing The Cyber Resilience Of The Smart Grid, Kesava Karishma Devi Dadi

Theses and Dissertations

This research focuses on the cyber-attack of the smart grid and its retrieval to a normal state by estimating the smart grid's resilience. This study developed a theoretical model to estimate the resilience of the smart grid using choice modeling. A utility function is formulated based on various factors and sub-factors of resilience to estimate the resilience of the smart grid. Choice modeling is applied to estimate the model parameters in various fields such as marketing, energy, transportation, and health and to predict the outcome.

Field Durability Test Of Clt Wall Envelope Using Physical Barriers Against Termites And Structural Performance Of Nailed Hold-Down Brackets Connected To Fungus-Exposed Clt Walls, Kamal Neupane

Theses and Dissertations

The effectiveness of using commercial polyethylene flashing and stainless-steel mesh in CLT wall systems as the termite barriers were evaluated in a short-term field test. American Wood Protection Association (AWPA) E21's visual ratings ranged from 10 to 9 in the specimens showing little damage when no physical barriers were used. Termites were able to crawl beyond the physical barriers in few specimens showing the necessity of further research on height and installation method of physical barriers. On the second part, the effect of decay caused due to Postia placenta, a brown-rot fungus, on the structural performance of hold-down brackets connected …

Catalytic Light Alkanes Selective Conversion Through Ammonia-Assisted Reforming, Siavash Fadaeerayeni

Theses and Dissertations

The fact that hydrogen is a clean and versatile fuel offers an attractive carbon-free source of energy and leverages the U.S. economy toward long-term sustainable economic growth. At an industrial scale, hydrogen production is mostly relying on methane steam reforming producing stoichiometric amounts of carbon oxides (CO and CO2), which imposes economic and environmental concerns. To mitigate the issue, we propose NH3 assisted anaerobic reforming of natural gas liquids (ethane and propane) as an alternative approach to produce COx free hydrogen. Here, in the first chapter, through comprehensive performance evaluation, characterization, and transient kinetic studies, it is shown that the …

Methods For Inference And Analysis Of Gene Networks From Rna Sequencing Data, Himangi Srivastava

Theses and Dissertations

RNA (Ribonuceic Acid) sequencing technology is a powerful technology used to give re- searchers essential information about the functionality of genes. The transcriptomic study and downstream analysis highlight the functioning of the genes associated with a specific biological process/treatment. In practice, differentially expressed genes associated with a particular treatment or genotype are subjected to downstream analysis to find some critical set of genes. This critical set of genes/ genes pathways infers the effect of the treatment in a cell or tissue. This disserta- tion describes the multiple stages framework of finding these critical sets of genes using different analysis methodologies …

Uncertainty-Aware Deep Learning For Prediction Of Remaining Useful Life Of Mechanical Systems, Samuel J. Cornelius

Theses and Dissertations

Remaining useful life (RUL) prediction is a problem that researchers in the prognostics and health management (PHM) community have been studying for decades. Both physics-based and data-driven methods have been investigated, and in recent years, deep learning has gained significant attention. When sufficiently large and diverse datasets are available, deep neural networks can achieve state-of-the-art performance in RUL prediction for a variety of systems. However, for end users to trust the results of these models, especially as they are integrated into safety-critical systems, RUL prediction uncertainty must be captured. This work explores an approach for estimating both epistemic and heteroscedastic …

The Development Of Authentic Virtual Reality Scenarios To Measure Individuals’ Level Of Systems Thinking Skills And Learning Abilities, Vidanelage L. Dayarathna

Theses and Dissertations

This dissertation develops virtual reality modules to capture individuals’ learning abilities and systems thinking skills in dynamic environments. In the first chapter, an immersive queuing theory teaching module is developed using virtual reality technology. The objective of the study is to present systems engineering concepts in a more sophisticated environment and measure students learning abilities. Furthermore, the study explores the performance gaps between male and female students in manufacturing systems concepts. To investigate the gender biases toward the performance of developed VR module, three efficacy measures (simulation sickness questionnaire, systems usability scale, and presence questionnaire) and two effectiveness measures (NASA …

Study Of Alloy And Process Modifications To Design Hydrogen Resilient High Hardness Steels, William R. Williams

Theses and Dissertations

High hardness steels (HHS) are vulnerable to hydrogen embrittlement, which can lead to rapid degradation of mechanical properties. Improved resistance to hydrogen embrittlement would be beneficial to many industries including construction, automotive, and military. A comparison study was performed to assess the hydrogen susceptibility of select commercially available and in-house designed HHS alloys. Slow strain rate tensile tests, performed with specimens charged with various levels of hydrogen, provided a macroscopic view of the onset of hydrogen embrittlement. Hydrogen permeation and thermal desorption spectroscopy tests determined the uptake and diffusivity of hydrogen through the material. The evaluation of hydrogen susceptibility for …

Development Of A Bioinspired Nugalbot For Precision Seeding Of Rice, Harsa Dhani

Theses and Dissertations

Many people around the world live in islands with mountainous lands. These people plant upland rice for their staple food. However, farming in these disadvantageous farms requires high input and gains low yield. One possible solution for improving productivity is by utilizing precision seeding. This study is focused on developing a robot for precision seeding of rice that is suitable for farming in rough terrain. A bioinspired human arm robot for picking seeds and making a hole on the ground was developed in accordance with Aalborg method for bioinspired design. Development of a mobile platform to carry the robot arm …

Testing Of Methods For Reducing Motivational Bias In Multi - Criteria Decision Analysis Problems, Chadwick Samuel Kerr

Theses and Dissertations

The idea of multi-criteria decision making has been around for quite a while. All judgement tasks are potential points of bias introduction. Each judgement task was assessed to identify common biases introduced through an extensive literature review for each task and bias. In several other studies, the distinction is made between cognitive and motivational biases. Cognitive biases are widely studied and well known with mitigations that have been validated. Motivational biases are judgements influenced by the decision maker’s desire for a specific outcome, also referred to as intentional bias, that are hard to correct and received very little testing and …

Design Of Plastic Contaminant Eliminator In Seed Cotton, Joshua H. Tandio

Theses and Dissertations

Plastic contamination in cotton is a problem in cotton industry and researchers have worked on this problem with different approaches. This thesis documents the design of mechanical and electronic real-time systems for detecting and removing plastic contaminants. The mechanical system was designed to expose plastic embedded inside the seed cotton to the sensor and to separate plastic contaminated cotton from the process stream. The detection system consisted of an embedded computer interfaced with a USB camera and Neural Network (NN) software running in it. Two NN models were tested, a transfer learning model and a built-from-scratch original model. The original …

The Development Of An Immersive Virtual Exploratory Engine (Ivee) For Immersive Analytics, Sofia Karam

Theses and Dissertations

Due to increasing data complexity, researchers are struggling to visually explore data using traditional methods. Research has shown that a variety of analytics-related tasks can be enhanced using new emerging technologies (e.g., virtual reality [VR] and augmented reality [AR]). This paper provides a detailed design approach for developing an immersive virtual engine system for conducting exploratory and descriptive data analytics. This system is called the Immersive Virtual Exploratory Engine (IVEE), is a VR system that allows users to experience full intractability with its graphical elements and examines various datasets within the same immersive environment. Basic plots—such as histograms, line plots, …

Detecting Malware In Memory With Memory Object Relationships, Demarcus M. Thomas Sr.

Theses and Dissertations

Malware is a growing concern that not only affects large businesses but the basic consumer as well. As a result, there is a need to develop tools that can identify the malicious activities of malware authors. A useful technique to achieve this is memory forensics. Memory forensics is the study of volatile data and its structures in Random Access Memory (RAM). It can be utilized to pinpoint what actions have occurred on a computer system.

This dissertation utilizes memory forensics to extract relationships between objects and supervised machine learning as a novel method for identifying malicious processes in a system …

Verification Of Acoustic Dissipation In Two-Phase Dilute Dispersed Flow Models In Computational Fluid Dynamics, Brennan Reeder

Theses and Dissertations

With existing numerical models for fluid particle systems in CHEM, the acoustic-particle interactions associated with two-phase dilute dispersed flow can be captured and the particle model can be validated using experimental and analytical data and verified using numerical techniques. The experimental and analytical data come from Zink and Delsasso and provides data for particles of diameters 5 to 15 microns for frequencies between 500Hz to 13600Hz. In the particle number density measurements by Zink and Delsasso there was a 10% estimated error range. Using the fourth order skew symmetric flux in CHEM and the built in Eulerian and Lagrangian particle …

Using A Systemic Skills Model To Build An Effective 21st Century Workforce: Factors That Impact The Ability To Navigate Complex Systems, Morteza Nagahi

Theses and Dissertations

The growth of technology and the proliferation of information made modern complex systems more fragile and vulnerable. As a result, competitive advantage is no longer achieved exclusively through strategic planning but by developing an influential cadre of technical people who can efficiently manage and navigate modern complex systems. The dissertation aims to provide educators, practitioners, and organizations with a model that helps to measure individuals’ systems thinking skills, complex problem solving, personality traits, and the impacting demographic factors such as managerial and work experience, current occupation type, organizational ownership structure, and education level. The intent is to study how these …

Predictive Computational Materials Modeling With Machine Learning: Creating The Next Generation Of Atomistic Potential Using Neural Networks, Mashroor Shafat Nitol

Theses and Dissertations

Machine learning techniques using artificial neural networks (ANNs) have proven to be effective tools to rapidly mimic first principles calculations. These tools are capable of sub meV/atom accuracy while operating with linear scaling with respect to the system size. Here novel interatomic potentials are constructed based on the rapid artificial neural network (RANN) formalism. This approach generates precise force fields for various metals that have historically been difficult to describe at the atomic scale. These force fields can be utilized in molecular dynamics simulations to provide new physical insights. The RANN formalism, which is incorporated into a LAMMPS molecular dynamics …

Mixing Temperature, Binder Content, And Dust Content Effects On Stone Matrix Asphalt, Abhinash Subedi

Theses and Dissertations

This study focuses on the effects of mixing temperature, binder content, and dust content on the performance of Stone Matrix Asphalt (SMA). Mixes produced at different mixing temperatures and with or without added polymer modified binder (P_b) and/or bag house dust (BHD) were evaluated. Two different types of specimens: laboratory mixed laboratory compacted, and plant mixed laboratory compacted were evaluated by Cantabro Mass Loss (CML) testing in an unaged condition or after a laboratory conditioning protocol (CP) was applied. Additional P_b and BHD were added to plant produced mixes in the laboratory before mixing. Results showed that …

Torque Vectoring To Maximize Straight-Line Efficiency In An All-Electric Vehicle With Independent Rear Motor Control, William Blake Brown

Theses and Dissertations

BEVs are a critical pathway towards achieving energy independence and meeting greenhouse and pollutant gas reduction goals in the current and future transportation sector [1]. Automotive manufacturers are increasingly investing in the refinement of electric vehicles as they are becoming an increasingly popular response to the global need for reduced transportation emissions. Therefore, there is a desire to extract the most fuel economy from a vehicle as possible. Some areas that manufacturers spend much effort on include minimizing the vehicle’s mass, body drag coefficient, and drag within the powertrain. When these values are defined or unchangeable, interest is driven to …

Enhancing Situational Awareness For Rotorcraft Pilots Using Virtual And Augmented Reality, Ardit Pranvoku

Theses and Dissertations

Rotorcraft pilots often face the challenge of processing a multitude of data, integrating it with prior experience and making informed decisions in complex, rapidly changing multisensory environments. Virtual Reality (VR), and more recently Augmented Reality (AR) technologies have been applied for providing users with immersive, interactive and navigable experiences. The research work described in this thesis demonstrates that VR/AR are particularly effective in providing real-time information without detracting from the pilot's mission in both civilian and military engagements. The immersion of the pilot inside of the VR model provides enhanced realism. Interaction with the VR environment allows pilots to practice …

Development And Evaluation Of An Improved Microbial Inactivation Model For Analyzing Continuous Flow Uv-Led Air Treatment Systems, Cole Holtom Thatcher

Theses and Dissertations

This thesis discusses the development of an improved microbial inactivation model for analyzing continuous flow UV-LED air treatment systems and use of the model to evaluate the impact of several treatment system design parameters on inactivation. Model development includes three submodels: a radiation submodel, a fluid flow submodel, and an inactivation kinetics submodel. Radiation modeling defines the UV irradiance throughout the system. Fluid flow modeling provides the residence times that microbes spend exposed to the UV irradiation while passing through the system. Inactivation modeling combines irradiance and residence times with inactivation kinetics to calculate species-specific inactivation in a treatment system. …

3d Permeability Characterization Of Sheared Fiber Reinforcement For Liquid Composite Molding Process Simulation, Collin William Childs

Theses and Dissertations

Resin transfer molding (RTM) is an infusion-based closed-mold manufacturing process where resin is injected into a preform of dry reinforcement to create a net shape part. Often, when a preform is draped over a mold with complex geometry, such as the double curvature of a dome, a reorientation of the fibers takes place in the form of in-plane shear. This deformation of the reinforcement structure has the potential to adversely affect the resin flow and the filling of the mold during RTM if the manufacturer fails to properly account for the shear effects. Various process simulation tools are being developed …

Partial Circuit Replication For Masking And Detecting Soft Errors In Sram-Based Fpgas, Andrew Mark Keller

Theses and Dissertations

Partial circuit replication is a soft error mitigation technique that uses redundant copies of a circuit to mask or detect the effects of soft errors. By masking or detecting the effect of soft errors on SRAM-based FPGAs, implemented circuits can be made more reliable. The technique is applied selectively, to only a portion of the components within a circuit. Partial application lowers the cost of implementation. The objective of partial circuit replication is to provide maximal benefit at limited or minimized cost. The greatest challenge of partial circuit replication is selecting which components within a circuit to replicate. This dissertation …

Thermal Transport To Impinging Droplets On Superhydrophobic Surfaces, Jonathan C. Burnett

Theses and Dissertations

An analytical model is developed to quantify the heat transfer to droplets impinging on heated superhydrophobic (SH) surfaces. Integral analysis is used to incorporate an apparent temperature jump at the superhydrophobic surface as a boundary condition. This Thesis considers the scenario of both isotropic and anisotropic slip, as would be realized on post-cavity style and rib-cavity style SH surfaces. This thermal model is combined with a hydrodynamic model which incorporates velocity slip at the surface. Use of the two models allows determination of the overall cooling effectiveness, a metric outlined in contemporary work. The effect of varying velocity slip and …

Method For Creating Subject-Specific Models Of The Wrist In Both Degrees Of Freedom Using Measured Muscle Excitations And Joint Torques, Blake Robert Harper

Theses and Dissertations

Two-thirds of repetitive strain injuries affect the wrist joint. Although force is believed to be one of the major factors, the forces involved in wrist movements have not been thoroughly characterized in vivo. Computer simulations with a musculoskeletal model of the wrist have been used to estimate wrist muscle forces, but only at maximum voluntary contraction and only involving a single degree of freedom (DOF). In this study we present a method for creating a subject-specific model that can be used to estimate muscle forces and joint torques in both degrees of freedom of the wrist over a range of …

Sensitivity Of Tremor Propagation To Model Parameters, Charles Paul Curtis Jr.

Theses and Dissertations

Although Essential Tremor (ET) is the most common type of tremor, many patients are left without satisfactory treatment options. One potential alternative treatment to medication or surgery is a wearable tremor-suppressing device. However, optimizing the effectiveness of such a device requires knowledge of which muscles/joints are most responsible for tremor. To answer this question, current efforts simulate tremor propagation using a model of the neuromusculoskeletal dynamics of the upper limb. To guide efforts to identify realistic model parameters and use the model to determine the mechanical origin of tremor, we performed preliminary parameter estimation work and a thorough sensitivity analysis …

Cedar: A Dimensionally Adaptive Flow Solver For Cylindrical Combustors, Ty R. Hosler

Theses and Dissertations

This thesis discusses the application, evaluation, and extension of dimensionally adaptive meshing to the numerical solution of velocity and pressure fields inside cylindrical reactors. Due to the high length to diameter ratios of many cylindrical reactor vessels the flow field can become axisymmetric, allowing for simplification of the governing equations and significant reduction in computational time required for solution. A fully 3D solver is developed from existing computational tools at BYU and validated against theoretical velocity profiles for pipe flow at various Reynolds numbers, as well as with experimental data for an axial-fired center jet with recirculating flow. Dimensionally adaptive …

The Effect Of Information Acquisition Automation And Workspace Design On Human Pattern Recognition For Information Fusion, Kellie L. Turner

Theses and Dissertations

Automation employed in information fusion systems is designed to help humans combine information derived from multiple sources to form a cohesive assessment of the situation. Research using the Levels of Automation model (Parasuraman, Wickens, and Sheridan, 2000) have produced conflicting results, which Patterson (2017) posited was because it focused solely on analytical processing while neglecting the effects of intuitive cognition. The present study examined how information acquisition automation affects the human’s ability to detect patterns in data needed to reach higher levels of information fusion. Results showed that when information acquisition was performed through manual operations, pattern recognition performance was …

Meta-Analysis Of Performance Characteristics Of Modern Database Schemas, Carter Grove

Theses and Dissertations

Industry and academia alike are more commonly using databases as solutions to advanced and complex problems. Unfortunately, not all database schemas are created equal and can yield different advantages in different areas. To try to understand what database schema might be best suited for a user’s needs, we sought out to distinguish how databases are measured against each other, what their performance characteristics are, and what advantages each type of database inherently possesses. To allow for the ingestion of data across the five different categories of database schemas, we used a met-analysis of past literature and aggregated the data to …