Engineering Commons^™

Best Practices For Reducing Construction Accidents Involving Hispanic Construction Workers, Michael E. Asuquo, Khalid Siddiqi

The Professional Constructor

The objective of this study was to determine best practices for reducing accidents among Hispanic construction workers. It was hypothesized that language barrier between the Hispanics and American workers contributed immensely to high rate of construction accidents on industrial projects. Accident case studies and questionnaire survey were both used. Data was collected through semi-structured interviews with Hispanic workers involved in industrial construction projects in Metro Atlanta. Findings from the study concluded that most accidents involving Hispanic workers were caused due to lack of communication from supervisors, ignorance of workers on work procedures, lack of equipment training, and worker negligence. Language …

Construction Management Internship: A Key Opportunity For Assessment And Continuous Curriculum Improvement, James S. Vaux, Bree Dority, Dana E. Vaux

The Professional Constructor

The internship is an integral part of most Construction Management curricula. Studies have noted the importance and reciprocal value of internships for the student, the employer, and the academic program. However, to date, no studies have specifically outlined the value internships provide to the CM program for assessment and evaluation. This paper examines the value of the CM internship as an indirect measure to assess and incorporate change into program curricula. With 10 years of qualitative and quantitative data collected from CM student interns, industry employers, and university internship supervisors, this study supports that CM internships are a valuable tool …

Stick Built Vs. Precut Wall Framing For New Home Construction: A Comparison Of Framing Labor Hours, Waste Hauls, And Purchase Orders, Eric A. Holt, Mark Laliberte, Tristan Grant, Jordan Dentz

The Professional Constructor

Due to many trends in the construction industry (material cost increase, labor shortages, supply chain issues, pandemic, market demand outpacing supply), the homebuilding industry is looking for alternative ways to frame homes. In response to the National Housing Endowment (NHE) Request for Proposal, the researchers reviewed the literature on the housing market’s current state regarding the scale and scope of the skilled construction framers shortage and the current market share of single-family framing method; stick-built vs. precut framing packages. Working with industry partners, the team analyzed time studies for multiple new home builds. It was found that precut wall framing …

Total Cost Of Ownership Of Battery-Powered Vs. Hardwired Sensor Faucets In Commercial And Educational Construction Projects, Marie Patterson, Blake Wentz

The Professional Constructor

Owners who are pursing the construction of a new commercial building are becoming increasingly more interested in the sustainability, energy efficiency and life cycle costs of their proposed project. These owners are asking designers and construction companies to develop innovative strategies to lower their utility use and total cost in their projects. One area of opportunity to meet this owner need is the decision to use sensor lavatory faucets that are either battery-powered or hardwired.Several construction projects of various types and locations were analyzed to determine the total cost of ownership of both types of sensor faucets over a 12-year …

An Evaluation Of Energy Consumption Comparing Conventional Water Treatment Plants To Microfiltration And Ultrafiltration Water Treatment Plants, Danielle Larsen

All Theses

The use of low-pressure, hollow fiber microfiltration (MF) and ultrafiltration (UF) membranes has become increasingly prominent in drinking water treatment plant configurations over the past 30 years. At the same time, the topics of energy efficiency and sustainability in industry are becoming progressively more important. Although MF and UF are highly successful in filtration, they are generally thought of as significant energy consumers; however, the data have not yet been available to compare multiple plants in various contexts to determine the factors that most affect energy use. This research compares the energy use of MF and UF treatment plants to …

Optimizing Crispr/Cas9-Mediated Knockdown Of Angptl3 In Liver Cell Lines And Mouse Hepatocytes, Meredith Reeves

All Theses

Familial hypercholesterolemia (FH) is a genetic condition characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C) that leads to an increased risk of developing cardiac disease early in life (Shah et al., 2020). Current treatments such as statins and PCSK9 inhibitors have helped lower LDL-C levels, however they require repeated administration every 4-6 weeks to remain effective (Raal et al., 2018). Angiopoietin-like 3 (ANGPTL3) is an inhibitor of plasma lipid metabolism that has become a promising molecular target for the treatment of FH. Individuals with non-functional copies of ANGPTL3 demonstrate low levels of plasma LDL-C and triglycerides, indicating a protective …

The Evacuation Simulation Of Wheelchair Users In A Building Fire: An Initial Dynamic Characterization Of Structural Egress Components, Haley Hostetter

All Theses

People with disabilities are one of the most vulnerable groups involved in building fires. According to the U.S. Fire Administration, in the United States alone, an estimated 700 home fires involve people with physical disabilities each year while over 1700 involve those with mental health disorders. Despite this, the current body of literature shows few studies focused on the evacuation of disabled people. This is a direct result of past and present social injustice on people with disabilities and has resulted in high injury and death rates during fires. To combat this, enrich the literature, and improve their experiences in …

Modeling Hierarchical Porous Electrodes With Tailored Anisotropic Structure, Debanjan Sarker

All Theses

Modern electric vehicles and consumer electronics applications demand high specific energy from Li-ion batteries, which can be charged and discharged faster. In the search for high specific energy, researchers have tried to make thicker battery electrodes which contain a greater proportion of active material. While chemical and structural modification of electrodes can help to increase the electronic conductivity of active material, the microstructure of porous electrodes can be engineered to enhance ion transport for fast charge and discharge. Previous research has shown that macropores introduced by directional freeze tape casting can enhance the performance of thick porous electrodes. For instance, …

Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome

All Theses

Current biological strategies for remediating trichloroethylene (TCE) in low pH aquifers (i.e., pH14C-TCE assay was developed to determine pseudo first-order rate constants for the degradation of TCE in microcosms containing soil and groundwater from the Boeing Michigan Aeronautical Research Center (BOMARC) superfund site, where the pH ranges from 4.1 to 4.9. The ¹⁴C-TCE assay was also adapted to calculate soil-normalized rate constants for data from this site, as well as data that Szwast²¹ collected from the Beltsville Agricultural Research Center (BARC). In addition to natural attenuation, biostimulation through amendments of methane and nutrients were also assessed. This treatment …

Rapidly Deployable Structures For Disaster Relief And Military Use, Jayson Leonard

All Theses

Rapidly deployable structures currently play a vital role in the recovery aspect of disaster-stricken areas and the safety of military personnel in hostile zones. More recently there has also been a need for the structures to deal with unforeseen disruptions caused by the COVID pandemic, such as COVID testing centers or backyard pop-up offices. These structures could be used in different environments and serve many other purposes. Along with the structural performance of these shelters, they need to integrate into systems set in place effortlessly. For that reason, four key factors were taken into consideration, namely (1) deployability (how difficult …

Data-Driven Distributed Modeling, Operation, And Control Of Electric Power Distribution Systems, Hasala Dharmawardena

All Dissertations

The power distribution system is disorderly in design and implementation, chaotic in operation, large in scale, and complex in every way possible. Therefore, modeling, operating, and controlling the distribution system is incredibly challenging. It is required to find solutions to the multitude of challenges facing the distribution grid to transition towards a just and sustainable energy future for our society. The key to addressing distribution system challenges lies in unlocking the full potential of the distribution grid. The work in this dissertation is focused on finding methods to operate the distribution system in a reliable, cost-effective, and just manner.

In …

Embedding A Grid Of Load Cells Into A Dining Table For Automatic Monitoring And Detection Of Eating Events, Mohammad Mayyan

All Dissertations

This dissertation describes a “smart dining table” that can detect and measure consumption events. This work is motivated by the growing problem of obesity, which is a global problem and an epidemic in the United States and Europe. Chapter 1 gives a background on the economic burden of obesity and its comorbidities. For the assessment of obesity, we briefly describe the classic dietary assessment tools and discuss their drawback and the necessity of using more objective, accurate, low-cost, and in-situ automatic dietary assessment tools. We explain in short various technologies used for automatic dietary assessment such as acoustic-, motion-, or …

Hierarchical And Distributed Architecture For Large-Scale Residential Demand Response Management, Pramod Herath Mudiyanselage

All Dissertations

The implementation of smart grid brings several challenges to the power system. The ‘prosumer’ concept, proposed by the smart grid, allows small-scale ‘nano-grids’ to buy or sell electric power at their own discretion. One major problem in integrating prosumers is that they tend to follow the same pattern of generation and consumption, which is un-optimal for grid operations. One tool to optimize grid operations is demand response (DR). DR attempts to optimize by altering the power consumption patterns. DR is an integrated tool of the smart grid. FERC Order No. 2222 caters for distributed energy resources, including demand response resources, …

Modeling, Estimation, And Optimal Control Of Lithium-Ion Battery At Cell And System Level, Hamidreza Mirzaei

All Dissertations

Lithium-ion batteries (LIBs) have been regarded as a crucial technology for electrifying a variety of applications, ranging from powering computers, phones, and hybrid electric vehicles (HEVs) to being a critical part of the modern centralized and distributed power grids. Battery systems performance is governed by embedded battery management systems (BMSs). The BMS includes battery state estimation algorithms and control rules, and it acts as the brain of battery-powered systems. The purpose of this research is to address unresolved difficulties associated with control algorithms in BMSs at all levels, from single battery cells to battery packs in hybrid electric vehicles (HEVs).\\ …

Design And Operations Of A New Facility In A Next Generation Logistic System Based On Horizontal Collaboration, Dilhani Marasinghe

All Dissertations

The growing amount of freight combined with systemic inefficiencies are stressing current logistic systems. Including horizontal collaboration in the future could provide significant help but this strategy will require several new types of facilities. The most flexible type of horizontal collaboration, however, required freight routing decisions to be made dynamically, in real time, and based on last minute information. This research explores one new facility type operating in this environment that handles a high throughput of pallets or pallet-like containers. A key design feature is how much storage these facilities should have to better coordinate outbound loads. The approach taken …

Mechanizing The Removal Of Soil Between Peach Trees Planted On Berms, Coleman Scroggs

All Theses

Armillaria root rot (ARR), primarily caused by the soilborne fungus Desarmillaria tabescens, has become the number one cause for peach tree decline in the Southeastern United States. Research has shown that planting peach trees on shallow berms and excavating the soil around the root collar two years after planting lessens the effects of ARR. However, berms make orchard operations such as pruning, thinning, and harvesting more cumbersome and cause cultural concerns as channels of water at their base can lead to erosion and the slope of the berms leads to herbicide and fertilizer runoff. The objective of this research was …

Sub-Bandgap Photon-Assisted Electron Trapping And Detrapping In Algan/Gan Heterostructure Field-Effect Transistors, Andrew Gunn

All Theses

We have investigated photon-assisted trapping and detrapping of electrons injected from the gate under negative bias in a heterostructure field-effect transistor (HFET). The electron injection rate from the gate was found to be dramatically affected by sub-bandgap laser illumination. The trapped electrons reduced the two-dimensional electron gas (2DEG) density at the AlGaN/GaN heterointerface but could also be emitted from their trap states by sub-bandgap photons, leading to a recovery of 2DEG density. The trapping and detrapping dynamics were found to be strongly dependent on the wavelength and focal position of the laser, as well as the gate bias stress time …

Park Equity Modeling: A Case Study Of Asheville, North Carolina, Anisa Young

All Theses

Parks and greenspaces are publicly available entities that serve the vital purpose of promoting multiple aspects of human welfare. Unfortunately, the existence of park disparities is commonplace within the park setting. Specifically, marginalized individuals encounter limited park access, insufficient amenity provision, and poor maintenance. To remedy these disparities, we propose a process in which we select candidate park facilities and utilize facility location models to determine the optimal primary parks from both existing and candidate sites.

We note that platforms currently exist to identify the geographical areas where residents lack sufficient access to parks. However, these platforms do not yet …

Controlled Manipulation Of Droplets On Fibers: Fundamentals And Printing Applications, Yueming Sun

All Dissertations

In this dissertation, the drop interactions with a single fiber is discussed under an application angle for the development on new Drop-on-Demand (DOD) printhead using a fiber-in-a-tube platform[1] to print highly viscous materials[2]. To control the drop formation and manipulation on fiber, one needs to know how the fiber wetting properties and the fiber diameter influence drop formation. And then, one needs to know the effects of fiber movement in the device on drop formation. These two questions constitute the main theme of this dissertation.

Before this study, it was accepted that the liquids could not form axisymmetric droplets if …

Snap : A Software-Defined & Named-Data Oriented Publish-Subscribe Framework For Emerging Wireless Application Systems, Manveen Kaur

All Dissertations

The evolution of Cyber-Physical Systems (CPSs) has given rise to an emergent class of CPSs defined by ad-hoc wireless connectivity, mobility, and resource constraints in computation, memory, communications, and battery power. These systems are expected to fulfill essential roles in critical infrastructure sectors. Vehicular Ad-Hoc Network (VANET) and a swarm of Unmanned Aerial Vehicles (UAV swarm) are examples of such systems. The significant utility of these systems, coupled with their economic viability, is a crucial indicator of their anticipated growth in the future. Typically, the tasks assigned to these systems have strict Quality-of-Service (QoS) requirements and require sensing, perception, and …

Characterization Of Thermal Gelation Properties In Bioresorbable Thermally Activated Hydrogel Polymers For Hernia Surgery Applications, Alexander Mayfield

All Theses

Hydrogel adhesives are a new class of materials with excellent biocompatibility, which makes them very attractive for biomaterial applications. It has been previously shown that Tetronic T1107, a four-arm poly (propylene oxide)-poly (ethylene oxide) (PPO-PEO) block copolymer, is useful as a chemical crosslinking thermo-responsive hydrogel for bioadhesive applications. The end groups of this polymer are modified with acrylate and N-hydroxysuccinimide (NHS) functional groups. The acrylate end group gives the polymer cohesive properties with long-range chemical crosslinking using dithiothreitol (DTT), while the NHS end group gives the polymer adhesive properties through bonding with amines found in organic tissue. It was found …

Development Of A Reverse Engineered, Parameterized, And Structurally Validated Computational Model To Identify Design Parameters That Influence American Football Faceguard Performance, William Ferriell

All Dissertations

Traumatic brain injury (TBI) continues to have the greatest incidence among athletes participating in American football. The headgear design research community has focused on developing accurate computational and experimental analysis techniques to better assess the ability of headgear technology to attenuate impacts and protect athletes from TBI. Despite efforts to innovate the headgear system, minimal progress has been made to innovate the faceguard. Although the faceguard is not the primary component of the headgear system that contributes to impact attenuation, faceguard performance metrics, such as weight, structural stiffness, and visual field occlusions, have been linked to athlete safety. To improve …

The Development And Analysis Of Methods Used To Evaluate American Football Facemasks, Alexander Bina

All Dissertations

The motivation for this Ph.D. dissertation is to provide football equipment managers, coaches, parents, athletes, and relevant industry personnel with an understanding of the implication a chosen football facemask design will have on the safety of the athlete. As athletes have increased their capacity for speed, size, and strength, so too has the head injury risk increased in American football. To align with the increase in head impact injury in American football, the protective head impact community must expand its capacity to evaluate protective equipment systems. This dissertation focuses specifically on one helmet system component: the football facemask. This dissertation …

3d Printed Multicomponent Polymer Based Materials Via Hybrid Filaments: Fabrication And Characterization, Erik Antonio

All Dissertations

Additive manufacturing, also known as 3D printing, promises a manufacturing revolution for both industry and academic circles. One of the most widely used method of 3D printing is Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF), which requires a thermoplastic filament to be directed towards a heating block and then deposited via extrusion layer by layer to produce a finished part. However, there are significant issues with this technology, mainly a limitation on the materials available for use and mechanical property deficiencies when compared to traditional manufacturing. These issues are brought about by the temperature limited nature of the …

Feasibility Of Using Ultra-High-Performance Concrete (Uhpc) As A Repair Material Durability Performance, Rebar Coating, And Bond Characterization, Haitham Hussein

All Dissertations

Ultra-High Performance Concrete can be a very good material for use in repair works. The ability of chloride ions to pass through repaired concrete layers is suppressed if an impermeable concrete like UHPC is used. However, thickness of the UHPC layer and the orientation of the repair layer relative to the direction of chloride ingress may influence its effectiveness. This study is an attempt to evaluate the effect of varying thicknesses and cross sections areas of UHPC over a precast concrete and the direction of the UHPC layers relative to the direction of chloride ion movement on the resistance offered …

Hybrid Smart Transformer For Enhanced Power System Protection Against Dc With Advanced Grid Support, Moazzam Nazir

All Dissertations

The traditional grid is rapidly transforming into smart substations and grid assets incorporating advanced control equipment with enhanced functionalities and rapid self-healing features. The most important and strategic equipment in the substation is the transformer and is expected to perform a variety of functions beyond mere voltage conversion and isolation. While the concept of smart solid-state transformers (SSTs) is being widely recognized, their respective lifetime and reliability raise concerns, thus hampering the complete replacement of traditional transformers with SSTs. Under this scenario, introducing smart features in conventional transformers utilizing simple, cost-effective, and easy to install modules is a highly desired …

Distributed Learning With Automated Stepsizes, Benjamin Liggett

All Theses

Stepsizes for optimization problems play a crucial role in algorithm convergence, where the stepsize must undergo tedious manual tuning to obtain near-optimal convergence. Recently, an adaptive method for automating stepsizes was proposed for centralized optimization. However, this method is not directly applicable to decentralized optimization because it allows for heterogeneous agent stepsizes. Furthermore, directly using consensus between agent stepsizes to mitigate stepsize heterogeneity can decrease performance and even lead to divergence.

This thesis proposes an algorithm to remedy the tedious manual tuning of stepsizes in decentralized optimization. Our proposed algorithm automates the stepsize and uses dynamic consensus between agents’ stepsizes …

The Physical Properties And Handling Characteristics Of Pelletized Biomass Materials, Ryan Dean

All Theses

Biomass and feed pellets can be handled and stored using similar equipment used for other bulk materials; however, their unique physical characteristics can lead to handling challenges. Understanding the flow characteristics of these materials is essential for handling and storage system design, but these characteristics are not well defined in less-than-ideal conditions. The overall objective of this study was to evaluate how moisture content and level of fines influence the angle of repose (AoR) of hardwood, pine bedding, and feed pellets along with determining the impacts of displacement on the shear stress of fuel pellets utilizing a modified linear wall …

Tissue-Engineered Living Pulmonary Valve For Young Adult Patients, Erica Hoskins

All Theses

Cardiovascular disease (CVD) is a non-communicable disease responsible for 659,000 deaths annually in the United States. While CVD can affect all components of the cardiovascular system, heart valve disease is responsible for 25,000 deaths yearly. Of specific interest is the pulmonary valve since there is limited research on resolving pathologies that affect it. Like the aortic and mitral valves, common pathologies include stenosis, regurgitation, and atresia. Notably, the pulmonary valve requires repair and replacement in pediatric patients and young adults due to congenital disabilities. Even with technological advances in valve replacements, limitations still present themselves for use with younger patients …

Bioleaching Of Arsenic From Agricultural Soils, Zachary Gilstrap

All Theses

Arsenic is a ubiquitous trace metalloid. However, increasing concentrations of arsenic in soil and water is a problem the world faces due to inputs from anthropogenic sources such as mining, milling, agriculture, and coal ash. One method of remediation for these arsenic-contaminated sites is bioleaching. While it is most often used to extract metals from raw ore, it is a viable and environmentally friendly method to remove the same metals from soil. Bioleaching removes metals by cultivating living organisms such as the fungi Aspergillus niger (A.niger) or the bacterium Thiobacillus ferrooxidans (T.ferrooxidans). This research aimed to investigate A. …