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Full-Text Articles in Engineering

Combat Assessment For The Simulation Of Warfare, Benjamin L. Finch Dec 2021

Combat Assessment For The Simulation Of Warfare, Benjamin L. Finch

Theses and Dissertations

Military assessment seeks to answer two primary questions: "are we creating the effects that we desire?" and "are we accomplishing tasks to standard?" This thesis steps through several desirable characteristics for a simulated combat assessment methodology. After developing a value hierarchy from these characteristics, this thesis provides and evaluates several candidate methodologies for use within a combat simulation. Each alternative's evaluation is informed by its application to a small combat simulation. Upon recommending the use of Linear Programming, we utilize value-focused thinking to modify this alternative. The thesis terminates with some conclusory thoughts and ideas for future research.


Investigation Of Mirror Satellite Concept To Augment Natural Lighting Conditions On Orbit, Daniel M. Dombrowski Dec 2021

Investigation Of Mirror Satellite Concept To Augment Natural Lighting Conditions On Orbit, Daniel M. Dombrowski

Theses and Dissertations

A method of augmenting on-orbit lighting conditions for rendezvous and proximity operations through the novel use of solar reflectors is presented. Natural lighting conditions on-orbit pose extreme challenges to these already complex missions. This research summarizes and applies the historical basis of solar reflectors to the proximity operations issues encountered today. Building on this past research, a simulation has been created to test the efficacy of a solar reflector constellation in facilitating less complex servicing/inspection missions. Initial testing has shown promising results for low mass membrane mirrors in augmenting illumination conditions with particular benefit in the geosynchronous orbital regime. Through …


Flow Choice Architecture: Cognitive Augmentation Of Knowledge Workers, Troy Ricardo Weekes Dec 2021

Flow Choice Architecture: Cognitive Augmentation Of Knowledge Workers, Troy Ricardo Weekes

Theses and Dissertations

The Flow Choice Architecture (FCA) is a biofeedback-based behavior modification tool that was designed for operation by human knowledge workers (KWs) before, during, and after the performance of work tasks. FCA utilizes human-aware artificial intelligence (AI) that senses patterns in its operator’s bio-signals to derive their cognitive and affective states. The states are contextualized using relevant information about the operator, task, and work timeline. The contextualized operator states are then used to recommend effective nudges that orient the human KW towards the flow state. This dissertation outlines the state-of-the-art on flow, neurofeedback, and AI then explains how FCA was designed, …


Smart Metering Communication Protocols And Performance Under Cyber Security Vulnerabilities, Oscar A. Alvarez Dec 2021

Smart Metering Communication Protocols And Performance Under Cyber Security Vulnerabilities, Oscar A. Alvarez

Theses and Dissertations

The communication process is the key that characterizes the modern concept of smart grid, a new technology that introduced a “two-way communication” in energy measurement systems and can be best represented through the smart meters. Hence, the goal of smart metering communication is to ensure a secure and reliable transmission of information that can only be accessed by end users and energy supplying companies. With the goal of improving the information security in smart energy grids, the research presented in this work focused on studying different advanced metering infrastructure communication protocols and, it showcases a series of experiments performed on …


Synthesize And Characterization Of Aluminum- Tungsten Carbide Nanocomposite, Shuvendu Das Dec 2021

Synthesize And Characterization Of Aluminum- Tungsten Carbide Nanocomposite, Shuvendu Das

Theses and Dissertations

This research focuses on developing metal matrix composite reinforced by polymer-derived ceramic fibers. The force-spun AMT nanofibers were heat treated into tungsten carbide and then mixed with aluminum powder using cold pressing and sintering to produce the composites. The basic mechanical properties of this composite are investigated by density measurement, hardness and compression testing. SEM, EDS and XRD were used to test the morphology of tungsten carbide fibers. EDS identified a near-perfect W-C ratio in tungsten carbide fibers 1000 °C. Tungsten Carbide fibers were crushed using ball milling technique. Tungsten carbide nanofibers powder had a variety of particle size. Results …


Development Of Metamaterial-Based Near-Zero Refractive Index Structures In The Optical Regime, Andres Ochoa Dec 2021

Development Of Metamaterial-Based Near-Zero Refractive Index Structures In The Optical Regime, Andres Ochoa

Theses and Dissertations

Multilayer combinations of plasmonic and dielectric materials can be designed as subwavelength structures to create a medium with unique parameters, but the development of optical metamaterials for the visible spectrum is hindered by the lack of plasmonic materials with suitable properties. A method to understand and design metamaterials for optical applications is examined as a solution for shifting the operating range from ultraviolet light to visible light. Special points of interest and corresponding parameters are identified to understand their effects on propagation. A hyperbolic near-zero refractive index metamaterial composed of alternating layers of metal and perovskite thin films is proposed …


Effects Of Graphical In-Flight Weather Information And Graphical Depictions Of Airspace Restrictions On Pilots’ Decisions To Continue Vfr Flight Into Imc, Andrew James Nakushian Dec 2021

Effects Of Graphical In-Flight Weather Information And Graphical Depictions Of Airspace Restrictions On Pilots’ Decisions To Continue Vfr Flight Into Imc, Andrew James Nakushian

Theses and Dissertations

Continued Visual Flight Rules (VFR) flight into Instrument Meteorological Conditions (IMC) is a leading cause of fatal general aviation accidents. According to the 2020 Joseph T. Nall Report, this type of accident has a 90% lethality rate. As a result of this high lethality rate, VFR into IMC is an aviation safety issue widely discussed among the aviation community in popular media and academic literature. Additionally, over the past decade, Electronic Flight Bags (EFBs) have become mainstream in general aviation, replacing paper charts and providing inflight weather in both graphical and textual form. EFBs also commonly provide graphical depictions of …


Evolutionary Algorithms For Function Model Synthesis, Amaninder Singh Gill Dec 2021

Evolutionary Algorithms For Function Model Synthesis, Amaninder Singh Gill

Theses and Dissertations

Function modelling plays an essential role in the systematic design process. Designers are trained in the academia trained on function models, yet the acceptance of function models in the industry remains sparse. A possible reason is that there is a lack of computational support for synthesizing function models. The research presented in this dissertation aims to fill that gap. A conceptual proof of function model synthesis using a Genetic Algorithm (GA) is initially presented. Thereafter a priori rules to evaluate function model have been developed. These rules do not rely on a designer conveying designer intent to the algorithm, which …


Thermoelectric-Based Cooling Systems For Building Application: A Sustainable Solution, Seyedehmohadeseh Seyednezhad Dec 2021

Thermoelectric-Based Cooling Systems For Building Application: A Sustainable Solution, Seyedehmohadeseh Seyednezhad

Theses and Dissertations

In the United States, buildings account for a large share of the annual energy consumption, nearly 40%. Fossil fuels including coal, oil, and natural gas account for the main source of electric power generation and constitute the largest portion of the building energy consumption. Such a high level of fossil fuel consumption is a multifaceted challenge as demand for energy grows, and natural resources become scarce and expensive, while the climatic effects of massive energy use will be clearly felt by all. As a necessary component for occupants’ thermal comfort, cooling and air conditioning systems are among the largest energy …


Feasibility Analysis And Performance Study Of A Pulsed Solid Propellant Integrated Propulsion System For Small Satellites, Tahir Kanchwala Dec 2021

Feasibility Analysis And Performance Study Of A Pulsed Solid Propellant Integrated Propulsion System For Small Satellites, Tahir Kanchwala

Theses and Dissertations

Solid propellant has come a long way since the 13th century when gunpowder was widely used as the go-to means in rocket propulsion. Of course, back then, rockets were not intended to carry humanity out of the atmosphere. Untill the introduction of liquid propellants in the mid-20th century, solid propellants were the foundation. Still, liquid propellants aimed to add more stability and controllability to rocketry and thus were preferred over their solid counterparts. This thesis seeks to analyze a novel type of propulsive device that aims to eliminate challenges faced by both types of fuels and instead utilize the advantages …


Socio-Economic Variables And Their Relationships With The Passenger To Population Ratio, Jack Matthew Westbury Dec 2021

Socio-Economic Variables And Their Relationships With The Passenger To Population Ratio, Jack Matthew Westbury

Theses and Dissertations

As the aviation industry expands and becomes commonplace in the modern world, it would behoove us to understand how the industry develops and passenger to population ratio could be a measure of that development. If called upon to identify how the aviation industry develops, one could only make suggestions as to which variables might be key in the development of the aviation industry. This study used existing socio-economic and population data from the United Nations and passenger information from the International Air Transport Association, with the aim to deepen the understanding of the relationship between socio-economic variables and the passenger …


Developing A Prototype Energy Harvesting Device For Powering Wireless Onboard Condition Monitoring Sensor Modules For Railway Service, Martin Amaro Jr. Dec 2021

Developing A Prototype Energy Harvesting Device For Powering Wireless Onboard Condition Monitoring Sensor Modules For Railway Service, Martin Amaro Jr.

Theses and Dissertations

An energy harvesting system is being developed to power a wireless bearing health monitoring device. In contrast to other monitoring systems, this wireless monitoring device is a low-powered onboard solution. Powered by a 3.7-Volt lithium-ion battery, the device can continuously function for several months on a single charge. By implementing an energy harvesting system, the life of the battery can be increased reducing the overall maintenance, electronic waste, and time needed to replace the batteries. The harvesting system uses thermoelectric generators to convert the heat generated in the bearings into electricity. The system is composed of aluminum heat sinks, a …


To A More Sustainable Construction Method For Electrically Conductive Heated Pavement Systems, Mohammad Anis Dec 2021

To A More Sustainable Construction Method For Electrically Conductive Heated Pavement Systems, Mohammad Anis

Theses and Dissertations

Snow and ice damage to the pavement in the United States, particularly in colder regions, costs the US economy millions of dollars each year. Conventional methods for keeping snow off roads after heavy snowfall are judged prohibitively expensive. As a result, an alternative solution is required to reduce costs while also improving pavement resiliency. An electrically heated pavement system (EHPS) has been regarded as a viable alternative to older approaches in recent years. The majority of earlier research concentrated on improving the conductivity characteristics of paving materials. On the other hand, this study takes a different approach by focusing on …


The Skeletal Structure Of Hot Mix Asphalt And The Effects Of Fiber Additives, Samantha A. Avila Dec 2021

The Skeletal Structure Of Hot Mix Asphalt And The Effects Of Fiber Additives, Samantha A. Avila

Theses and Dissertations

Hot mix asphalt (HMA) has proven to be successful in providing a proper paving surface for transportation services throughout the world. Asphalt pavement could be altered as the gradation of the mixture is adjusted. For instance, mixtures could vary from Dense Graded (DG) that contain a fairly even percentage of all aggregate size allowing for a more compact fit to Stone Matrix Asphalt (SMA) where the coarse aggregate compromise the main skeleton while fine aggregate fills the voids. This study investigates the effects of fibers and skeletal structures on mechanical properties of HMA. Two types of fiber additives are tested …


Synthesis And Characterization Of Copper Oxide Nanofibers, Shishir Barai Dec 2021

Synthesis And Characterization Of Copper Oxide Nanofibers, Shishir Barai

Theses and Dissertations

The aim of this study was to develop polymer-derived Copper (II) Oxide (CuO) nanofibers through centrifugal spinning technique and subsequent calcining. To obtain the force spun pre-ceramic copper acetate nanofibers, 15% wt, 25% wt, 35% wt, 50% wt% copper acetate (active material) and poly (vinyl) alcohol ( PVA) solutions was prepared with deionized water (DI) as solvent and spun at 7500 rpm in a FibeRio Cyclone. Thermogravimetric analysis (TGA) was implemented to determine the thermal degradation behavior of the pre-ceramic nanofibers. These nanofibers were then calcined at three different temperatures (500, 600 and 700°C) to produce CuO nanofibers. The microstructure, …


Lubrication Performance Of Vegetable Oils Modified With Halloysite Clay Nanotubes (Hnt) As Lubricant Additives, Md Abu Sayeed Biswas Dec 2021

Lubrication Performance Of Vegetable Oils Modified With Halloysite Clay Nanotubes (Hnt) As Lubricant Additives, Md Abu Sayeed Biswas

Theses and Dissertations

Vegetable oil-based nano-lubricants are a great alternative to petroleum-based lubricants because of their less adverse impact on the environment. This work evaluates the tribological performance of sunflower, corn, and peanut oils modified with halloysite clay nanotubes (Al2Si2O2(OH)2nH2O) as lubricant additives at different concentrations. To analyze the tribological performance of the nano-lubricants, a block-on-ring tribometer was used following the ASTM G-077-17 standard procedure. Characterization of HNT was carried out by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). The effect of the HNT on the lubrication performance of the newly developed vegetable oil-based nano-lubricants was evaluated, and the …


Assessing The Effectiveness And Efficacy Of Wireless Onboard Condition Monitoring Modules In Identifying Defects In Railroad Rolling Stock, Lee R. Cantu Dec 2021

Assessing The Effectiveness And Efficacy Of Wireless Onboard Condition Monitoring Modules In Identifying Defects In Railroad Rolling Stock, Lee R. Cantu

Theses and Dissertations

Many industries have begun shifting into the Internet of Things (IoT) in the 21st century. To help ease this transition for the rail industry, The University Transportation Center for Railway Safety (UTCRS) has partnered with Hum Industrial Technology, Inc. (HUM) to help complete the development of a Wireless Onboard Condition Monitoring system named the ‘Boomerang™’. This product allows customers to schedule proactive maintenance on their railcars to replace defective wheels and/or bearings, saving them time, money and potentially preventing costly catastrophic derailments. The UTCRS research team has established thresholds to determine defective bearings utilizing thermal and mechanical sensors.

The effectiveness …


Molecular Dynamics Study Of Atomic Diffusion In Cantor High Entropy Alloy In The Selective Laser Melting Process, Mathew Z. Farias Dec 2021

Molecular Dynamics Study Of Atomic Diffusion In Cantor High Entropy Alloy In The Selective Laser Melting Process, Mathew Z. Farias

Theses and Dissertations

High entropy alloys (HEAs) are compositionally complex alloys that are comprised of 5 or more principle elements at near equimolar concentrations. The Selective Laser Melting (SLM) method generally melts pure elemental powders or prefabricated alloy powders, this process allows for the production of heterogeneous structures that would be difficult to create through more conventional means. In-situ alloying in SLM, or Laser Additive Alloying (LAA), using pure elemental powders is a promising means of producing what would otherwise be costly and difficult to fabricate products with less defects using prefabricated powders, therefore this new approach could enable the ability to …


Life-Cycle Cost Analysis Of The Efficient Water Fixtures And Electric Appliances Used To Minimize Water And Energy Consumption In Homes In The U.S, Miranda N. Garcia Dec 2021

Life-Cycle Cost Analysis Of The Efficient Water Fixtures And Electric Appliances Used To Minimize Water And Energy Consumption In Homes In The U.S, Miranda N. Garcia

Theses and Dissertations

Consumer interest in incorporating sustainability and efficient appliances into daily life has been growing in the past several years. While reducing their environmental impact may be a draw to some, by making the switch to water- and energy-efficient appliances many homeowners are enticed by the promise of long-term savings on utility bills. Programs such as WaterSense and Energy Star not only offer certified efficient appliances and fixtures, but they may also certify water- and energy-efficient homes. Additionally, the United States Green Building Council (USGBC) offers the LEED program (Leadership in Energy and Environmental Design) which certifies homes in a similar …


A Gis-Based Model To Assess On-Site Sewage Facility (Ossf) Contamination Risk To Local Water Resources, Alvaro Garcia Dec 2021

A Gis-Based Model To Assess On-Site Sewage Facility (Ossf) Contamination Risk To Local Water Resources, Alvaro Garcia

Theses and Dissertations

In a collaborative effort between Texas Water Resources Institute (TWRI), Cameron County Public Health (CCPH), Texas A&M AgriLife Extension (TAMAE), and the University of Texas Rio Grande Valley (UTRGV), a GIS database that includes relevant OSSF information, such as location, system age, lot size, and other important parameters was created.

This OSSF database, along with publicly available GIS data, was used to create an integrative GIS-based risk assessment model where OSSF risk parameters were assigned a risk factor and combined into a spatial contamination risk for surrounding areas and their receiving waterbodies. Parameters were broken down into two categories: environmental …


Synthesis And Characterization Of Centrifugally Spun Molybdenum-Based Nanomaterials For Lithium-Ion Batteries, Ramiro Gonzalez Jr. Dec 2021

Synthesis And Characterization Of Centrifugally Spun Molybdenum-Based Nanomaterials For Lithium-Ion Batteries, Ramiro Gonzalez Jr.

Theses and Dissertations

The work presented in this thesis focuses on the processing and development of transition metal compound composite fibers as anode materials for rechargeable lithium-ion batteries (LIBs). Among the transition metal compounds, molybdenum compounds have risen as promising candidates of advanced electrode materials, in view of their natural abundance, virtuous mechanical/thermal stability, rich chemistry, high theoretical specific capacity, and multiple oxidation states of Mo. The current work reports synthesize MoO2/C and MoO3/C composite fibers drawn from centrifugal spun ammonium molybdate/PAN precursor fibers, followed by a thermal treatment stabilizing in air and calcination under argon atmosphere. The weight ratios of (MoOx, 2 …


Development Of A Compact Core Flooding Apparatus For Matrix Acidizing Applications, Antonio Hernandez Zuniga Dec 2021

Development Of A Compact Core Flooding Apparatus For Matrix Acidizing Applications, Antonio Hernandez Zuniga

Theses and Dissertations

Matrix Acidizing is defined as a well stimulation technique in which the acid is injected into the formation with the purpose of dissolving the minerals present and thus enhancing the permeability of the formation and facilitating the extraction of oil and/or gas from the formation. The primary goal of acid diversion is the creation of wormholes and ramification paths that allow the fluid to flow from the higher to the lower permeability zones of the limestones, sandstones or carbonate reservoirs. Naturally, as the injected acid will follow vugs, fractures and pores, HCl is used because of its quick reaction and …


Data Analytics For Google Trend Search Result Of Illness Symptoms, Md Jakir Hossain Dec 2021

Data Analytics For Google Trend Search Result Of Illness Symptoms, Md Jakir Hossain

Theses and Dissertations

The outbreak of COVID-19 has escalated from March 2020. Since then, people from all over the world are curiously searching different types of illness symptoms including corona virus. Before the outbreak, people were also searching different types of symptoms at different times. Both diseases share same symptoms, but in the flu season. If certain types of symptoms are visible at summer season, then these symptoms are for corona virus. The main purpose of our study is to find out this discriminative information from these search result. We will discuss some mathematical concepts and then develop an algorithm based on those …


Characteristics Analysis Of Electrochemical Impedance Spectroscopy (Eis) For Different Electrode Patterns, Shanzida Kabir Dec 2021

Characteristics Analysis Of Electrochemical Impedance Spectroscopy (Eis) For Different Electrode Patterns, Shanzida Kabir

Theses and Dissertations

Electrochemical impedance spectroscopy (EIS) is a rapidly developing technique used in characterizing materials and interfaces. Using equivalent circuits as models can determine the electrical properties of heterogeneous systems like membranes or electrolytes. Different electrochemical processes like the electron transfer rate of a specific reaction or the capacitive behavior of the system, or even the diffusion-limited response can coincide. EIS is applicable to determine different electrochemical processes that can happen simultaneously. The purpose of this research is to find the optimal operating range for other AC electrokinetic mechanisms. Analysis of EIS can be helpful in both fundamental examinations of electrokinetic transport …


Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez Dec 2021

Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez

Theses and Dissertations

Natural titanium diboride (TiB2) has been reported the 5th hardest material on earth. Due to its superior properties, such as high density, high elastic modulus, and high compressive strength, TiB2 becomes one of the most suitable ceramic reinforcements for applications with severe friction and heavy loading conditions. This study is intended to produce TiB2 using 3D additive manufacture (AM) technology, and then to understand the tribological property of the AM fabricated TiB2 specimens. In this study, a laser additive alloying (LAA) process was developed based on a Renishaw AM laser system. One mm thick samples were prepared using the LAA …


Development Of Vegetable Oil-Based Nano-Lubricants Using Montmorillonite Clay (Mmt) Nanoparticles As Lubricant Additives, Md Mashfiqur Rahman Dec 2021

Development Of Vegetable Oil-Based Nano-Lubricants Using Montmorillonite Clay (Mmt) Nanoparticles As Lubricant Additives, Md Mashfiqur Rahman

Theses and Dissertations

Because of the environmental impact and price volatility, there has been a growing concern on the use of petroleum-based lubricants. This issue has stimulated research into the development of biodegradable lubricants like vegetable oils. In this study, the tribological and rheological behavior of sunflower, peanut, and corn oils modified with Montmorillonite nanoclay (MMT) as lubricant additives were evaluated at various concentrations. A custom-made block on ring tribotester was used to evaluate the wear and friction characteristics of the nano-lubricants, following the ASTM G-077-05 standard. The effects of concentration and shear rate on shear viscosity were studied using a parallel plate …


High Performance Electromagnetic Interference Shielding From Lightweight-Flexible Polymer Composite Fiber Structures, Fariha Rubaiya Dec 2021

High Performance Electromagnetic Interference Shielding From Lightweight-Flexible Polymer Composite Fiber Structures, Fariha Rubaiya

Theses and Dissertations

This study focuses on the development and characterization of fiber-based polymer composite structures with the goal of developing high performance, flexible, lightweight, and cost-effective materials for electromagnetic interference shielding and piezoelectricity. Polyvinylidene fluoride (PVDF) was used as the base fiber mat while polyaniline (PANI), polypyrrole (PPY), polyindole (PIN), polydiacetylene (PDA) and Zn2GeO4 (ZGO) were incorporated via solution mixing and in-situ polymerization. The PVDF fine fiber systems were produced using the Forcespinning® method. Morphology, structure, thermal stability, electrical properties, EMI shielding effectiveness and piezoelectric performance of the fiber mats were analyzed. The composite system containing 1.25 wt. % of ZGO-PVDF displayed …


Approaches To Improve The Execution Time Of A Quantum Network Simulation, Joseph B. Tippit Dec 2021

Approaches To Improve The Execution Time Of A Quantum Network Simulation, Joseph B. Tippit

Theses and Dissertations

Evaluating quantum networks is an expensive and time-consuming task that benefits from simulation. A potential improvement is to utilize GPUs, namely by leveraging NVIDIA's programming framework, CUDA. To avoid performance pitfalls of higher level languages and programming models such as the so called "two language problem," the Julia Programming Language provides the basis for the development effort. This research develops a two module prototype quantum network simulation framework using GPUs and Julia. Performance of the software is measured and compared against other languages such as MATLAB.


Using Custom Ner Models To Extract Dod Specific Entities From Contracts, Kayla P. Haberstich Dec 2021

Using Custom Ner Models To Extract Dod Specific Entities From Contracts, Kayla P. Haberstich

Theses and Dissertations

The Air Force Sustainment Center collected 3.7 million contracts onto the Air Force Research Laboratory’s high power computers. They are in the format of a .pdf or scanned document, making them unstructured data. The Data Analytics Resource Team extracted the documents into a textual format for use in further analysis. This thesis looks to extract four DOD specific entities (NSN, Part Number, CAGE Code, and Supplier Name) from the contracts using custom NER models. This newly extracted information will allow the Air Force to identify what parts are supplied by which vendors. This information along with historical CLIN pricing for …


The Effect Of Shot Dependency On Composite Materials Subject To Ballistic Testing, Clayton C. Hankins Dec 2021

The Effect Of Shot Dependency On Composite Materials Subject To Ballistic Testing, Clayton C. Hankins

Theses and Dissertations

Ballistic analysis was performed on four common composite armor materials: 3k standard modulus plain weave carbon fiber, 8HS satin weave S-glass fiber, plain weave Kevlar® KM2 600 Denier fiber, and Spectra Shield® 4232 ultra-high molecular weight polyethylene to determine shot dependency based upon shot-to-shot impact distance, degree of penetration from the initial impacts, and the delamination effects from the initial impact. The primary measure of ballistic performance was the projectile velocity which represents a 50% probability of penetration, V50. This velocity was determined using a three-phase optimal design test method with an average of twelve shots per test. …