Engineering Commons^™

Nanocellulose Conduits For Enhanced Regeneration Of Peripheral Nerve Injuries, Nicklaus R. Carter

Electronic Theses and Dissertations

Peripheral neuropathy is estimated to afflict 20 million people in the United States. Most cases of neuropathy result from physical injuries and trauma arising from automobile accidents and war. Peripheral nerves have the intrinsic ability to regenerate over time, bridging the injury gap. However native regeneration is limited to a distance of only a few millimeters. Current methods utilized to assist in the regeneration of peripheral nerves over distances exceeding those amenable to native repair include nerve autografts and allografts, and implantation of conduits. Nerve autografts are regarded as the most effective method but require a second surgical site to ...

Development Of Hybrid Ultra-High Performance Concrete Thermoplastic Composite Panels For Blast And Ballistic Protection, Alyssa M. Libby

Electronic Theses and Dissertations

In recent years, ultra-high performance concrete (UHPC) has become a material of interest for structures needing resistance to impact and blast loadings. These types of loadings have induced brittle flexural failure in UHPC due to punching shear from the impactor. One way to improve the impact resistance, energy absorption, and ductility of UHPC is by adding fiber-reinforced polymer (FRP) skins to the front and rear faces of the concrete, resulting in a sandwich configuration. In this study, E-glass fiber-reinforced thermoplastic laminates were bonded to UHPC panels using a heated consolidation process known as stamp thermoforming. The bond between the UHPC ...

Handling And Manipulation Of Water- And Air- Borne Biological Samples Using Liquid-Infused Surfaces, Daniel P. Regan

Electronic Theses and Dissertations

Research on novel materials to handling water- and airborne samples for biological threats analysis is in great demand due to the COVID-19 pandemic. Work conducted on a new field of material science, called liquid-infused surfaces, demonstrate strong potential for the handling and manipulation of biological samples. As a result of the field’s infancy, only a limited number of studies have explored how liquid-infused surfaces can apply droplet manipulation strategies to address real-world problems. Presented in this dissertation are two platforms that leverage liquid-infused surfaces to address the challenges associated with handling water- and airborne biological samples. When dealing with ...

Nanoscale Spatial Realization Of Grain Boundary Defects And Its Passivation In Perovskite Solar Cells, Ashraful Haider Chowdhury

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) have seen significant improvement in photovoltaic performance in recent days. However, the performance of PSCs is limited by the defects present at grain boundaries (GB). The study adapted here discusses the nanoscale spatial realization of grain boundary defects and its passivation in perovskite solar cells. Conventional MAPbI3 and state- of-the-art Cs5(MA0.17FA0.83)95Pb(I0.83Br0.17)3-FAMACs perovskite GBs were studied in detail using atomic force microscopy. The density of trap states calculation by kelvin probe force microscopy (KPFM) shows that FAMACs perovskites have lower defects at GB compared with MAPbI3 perovskites. This improvement ...

Effect Of Surface Roughness And External Loading On Embedment In Steel And Aluminum Bolted Joints, Nathan Stang

Electronic Theses and Dissertations

Embedment in bolted joints is defined as the local deformation of surfaces into one another due to uneven contact. Embedment that occurs after the tightening of a bolted joint can cause loss of preload in the joint potentially leading to failure. VDI 2230, a German standard for bolted joint design, is currently the main source for engineers regarding embedment. It related expected embedment to the surface roughness in steel bolted joints. This research expands on the VDI standard by performing tests on a commonly used aluminum alloy and a steel alloy. Both cold rolled 1045 steel and 6061- T6511 aluminum ...

Develop Biochar-Based Controlled Release In Nitrogen Fertilizers, Zhisheng Cen

Electronic Theses and Dissertations

The current efficiency of conventional nitrogenous fertilizers (e.g. urea, ammonium sulfate, etc.) in agricultural practices is low, fluctuating from 30 to 40%. Approximately 60% of nitrogenous fertilizers were wasted due to vaporization into the air, runoff or leaching into water systems. The lost nitrogen (N) resulted in not only high production cost but also serious environmental problems, such as greenhouse gas (N2O) emission in the atmosphere, algal blooms, oxygen depletion, fish kills, and loss of biodiversity in surface water due to eutrophication or pollution. To address these problems, this study aimed to utilize low-cost biochar-based materials to develop a ...

Hyperspectral Empirical Absolute Calibration Model Using Libya 4 Pseudo-Invariant Calibration Site, Manisha Das Chaity

Electronic Theses and Dissertations

The objective of this paper is to find an empirical hyperspectral absolute calibration model using Libya 4 pseudo-invariant calibration site (PICS). The approach involves using the Landsat 8 (L8) Operational Land Imager (OLI) as the reference radiometer and using Earth Observing One (EO-1) Hyperion, with a spectral resolution of 10 nm as a hyperspectral source. This model utilizes data from a region of interest (ROI) in an “optimal region” of 3% temporal, spatial, and spectral stability within the Libya 4 PICS. It uses an improved, simple, empirical, hyperspectral Bidirectional Reflectance Distribution function (BRDF) model accounting for four angles: solar zenith ...

Nitrate And Phosphate Removal From Denitrification Bioreactors Using Woodchips, Steel Chips And Agricultural Residue Media, Abdoul Aziz Kouanda

Electronic Theses and Dissertations

Nitrate and phosphate present in agricultural subsurface drainage water can impact surface water quality thus impacting the environment and human health by causing eutrophication and Methemoglobinemia in young infant. Biological denitrification and phosphate adsorption filters are treatments options that can help reduce nitrate and phosphate concentration from agricultural subsurface drainage before it can be discharged in surface water. The first objective of this dissertation was to determine the Michaelis-Menten kinetics model parameters for nitrate removal in bioreactors using the fresh, aged, and composted woodchips. The composted woodchips achieved a denitrification rate 2.4 times higher than the fresh woodchips which ...

Human-Robot Collaboration Enabled By Real-Time Vision Tracking, Travis Deegan

Electronic Theses and Dissertations

The number of robotic systems in the world is growing rapidly. However, most industrial robots are isolated in caged environments for the safety of users. There is an urgent need for human-in-the-loop collaborative robotic systems since robots are very good at performing precise and repetitive tasks but lack the cognitive ability and soft skills of humans. To fill this need, a key challenge is how to enable a robot to interpret its human co-worker’s motion and intention. This research addresses this challenge by developing a collaborative human-robot interface via innovations in computer vision, robotics, and system integration techniques. Specifically ...

Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa

Electronic Theses and Dissertations

A location-specific evaluation of hydrological landscape responses concerning past and projected climate and land use land cover (LULC) changes can provide a powerful intellectual basis for developing efficient and profitable agroecosystems, and overcoming uncertain and detrimental consequences of LULC and climate shifts. This dissertation assessed the impacts of land use, management, and climate change on water resources in the Missouri River Basin (MRB) through four specific studies that included: (i) to study the responses of leached nutrient concentrations and soil health to winter rye cover crop (CC) under no-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation, (ii ...

Mechanically Spliced Precast Bridge Columns, Ted Sjurseth

Electronic Theses and Dissertations

Mechanical bar splices provide an alternative to the traditional method of lap splicing to achieve reinforcement bar continuity in reinforced concrete. Even though mechanical bar splices can be used as new precast column connections to accelerate the bridge construction (ABC), The use of bar couplers in the plastic hinge region of bridge columns is prohibited by the current US codes since the effects of bar couplers on the seismic behavior of columns is not fully investigated. A bridge column including precast columns with couplers located in a high seismic region must be designed to handle large inelastic lateral deformations. The ...

Lightweight Encryption Based Security Package For Wireless Body Area Network, Sangwon Shin

Electronic Theses and Dissertations

As the demand of individual health monitoring rose, Wireless Body Area Networks (WBAN) are becoming highly distinctive within health applications. Nowadays, WBAN is much easier to access then what it used to be. However, due to WBAN’s limitation, properly sophisticated security protocols do not exist. As WBAN devices deal with sensitive data and could be used as a threat to the owner of the data or their family, securing individual devices is highly important. Despite the importance in securing data, existing WBAN security methods are focused on providing light weight security methods. This led to most security methods for ...

A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu

Electronic Theses and Dissertations

The increasing application of geographic information system (GIS) technology in watershed modeling makes is necessary to further evaluate its impacts on runoff characteristics as a basis for improved hydrologic analysis in ungauged watersheds. Experts in the field of water resources and hydrology have recommended the practice of subdivision when modeling a watershed, and the use of observed data from hydrologically similar watershed to calibrate and validate an ungauged watershed’s model. However, previous studies have failed to adequately address the issues of watershed heterogeneity, spatial and temporal variability in physical parameters, GIS data resolution issues, including artifacts in automated extraction ...

Human Activity Recognition Based On Wearable Flex Sensor And Pulse Sensor, Xiaozhu Jin

Electronic Theses and Dissertations

In order to fulfill the needs of everyday monitoring for healthcare and emergency advice, many HAR systems have been designed [1]. Based on the healthcare purpose, these systems can be implanted into an astronaut’s spacesuit to provide necessary life movement monitoring and healthcare suggestions. Most of these systems use acceleration data-based data record as human activity representation [2,3]. But this data attribute approach has a limitation that makes it impossible to be used as an activity monitoring system for astronavigation. Because an accelerometer senses acceleration by distinguishing acceleration data based on the earth’s gravity offset [4], the ...

High Fidelity Computational Modeling And Analysis Of Voice Production, Weili Jiang

Electronic Theses and Dissertations

This research aims to improve the fundamental understanding of the multiphysics nature of voice production, particularly, the dynamic couplings among glottal flow, vocal fold vibration and airway acoustics through high-fidelity computational modeling and simulations. Built upon in-house numerical solvers, including an immersed-boundary-method based incompressible flow solver, a finite element method based solid mechanics solver and a hydrodynamic/aerodynamic splitting method based acoustics solver, a fully coupled, continuum mechanics based fluid-structure-acoustics interaction model was developed to simulate the flow-induced vocal fold vibrations and sound production in birds and mammals. Extensive validations of the model were conducted by comparing to excised syringeal ...

Understanding Biomass Upgrading Through Hydrogenolysis Reactions: Kinetics And Mechanism, Jalal Tavana

Electronic Theses and Dissertations

This dissertation involves several hydrogenolysis reactions but is mainly focused on hydrodechlorination (HDC) of chlorobenzene (PhCl) and hydrodeoxygenation (HDO) of 2-furancarboxylic acid (FCA). Hydrodechlorination of PhCl has been the subject of research for some time. Here, we used a Pd/C catalyst to study this reaction though rigorous kinetics and mechanistic analyses in a CSTR reactor. The H₂/D₂ kinetic isotope effect (KIE) experiment revealed that H₂ is not involved in a rate controlling step. The kinetics data are in agreement with similar systems reported before and follow a first-order dependence on chlorobenzene, half order for hydrogen ...

Durability Of Entrapped Gas In Quasi-Saturated Porous Media: Two Geotechnical Perspectives, Babak Mahmoodichanzab

Electronic Theses and Dissertations

Entrapped gas bubbles in quasi-saturated porous media are of practical importance in the field of science and engineering. Gas bubbles, which may occur naturally or be introduced artificially, significantly influence the mechanical behavior of soil. In this study, the durability of gas is examined from two geotechnical engineering perspectives. In the field of geotechnics, the artificial introduction of gas is being considered, as it has been widely recognized that entrapped gas, even in nearly-saturated sediments, has an appreciable influence on soil’s mechanical behavior. Entrapped gas bubbles in quasi-saturated sediments significantly increase the pore fluid compressibility and suppress the generation ...

Identifying The Need For Trained Machinists In The Greater Tri-Cities Area, Bradley Stufflestreet

Electronic Theses and Dissertations

Machinists are skilled tradespeople responsible for running a variety of machine tools to produce precision components for end-users or use in other manufacturing. This project identifies the current and future change in the number of machinists in the Tri-Cities area, especially the five-county service area of Northeast State Community College. Using an industry survey, the need for machinists is identified and evaluated to understand local employers’ needs. The results indicate industry needs more machinist to keep up with demand, as 6 out of 14 companies have open positions and, 8 reported difficulty filling openings. Furthermore, most companies are growing or ...

Hydrogenation Of 2-Methylnaphthalene In A Trickle Bed Reactor Over Bifunctional Nickel Catalysts, Matthew J. Kline

Electronic Theses and Dissertations

Biomass thermal conversion processes, such as pyrolysis, tend to produce mixtures of mono- and poly-aromatic species. While the high aromatic content is desirable in gasoline fractions, middle-distillate cuts, particularly jet fuel and diesel, require upgrading via hydrogenation and ring opening to achieve better combustion characteristics. There have been many proposed methods for producing drop-in fuels from woody biomass, one of them being Thermal DeOxygenation (TDO). The TDO process converts organic acids from cellulose hydrolysis into a low-oxygen bio-oil containing large amounts of substituted naphthalene compounds.

Poly-aromatic molecules, such as those found in TDO oil, have low cetane numbers (CN), particularly ...

An Exercise Device Used To Achieve Bone Formation Metrics For The Strengthening Of The Proximal Femur., Sean P. Coyle

Electronic Theses and Dissertations

Lateral falls often lead to hip fracture particularly in the elderly who have low bone mineral density. These fractures frequently lead to indirect mortality soon after injury. Normal use over the course over a lifetime leads to optimized adaptation of the bone in the proximal femur according to normal loading. A lateral fall generates non-normal, lateral loading at the proximal hip where the bone has not adapted to withstand such loading. The resulting fracture is generated by reversed strains on the bone tissue in the femoral neck in the hip in contrast to vertical, quotidian loading. Modern practices for preventing ...

Wave Attenuation Capacity Of Suspended Aquaculture Structures With Sugar Kelp And Mussels, Longhuan Zhu

Electronic Theses and Dissertations

Large aquaculture systems may have the potential to damp wave energy for coastal protection. The performance of these systems are influenced by the dynamics of components such as flexible kelp blades and mussel droppers. In this thesis, the dynamics of kelp blades and mussel droppers were investigated with a consistent-mass cable model with focus on understanding the asymmetric motion of kelp blades. The results showed the asymmetric blade motion in symmetric waves is caused by the spatial asymmetry of the encountered wave orbital velocities due to blade displacements and the asymmetric action on the blade by vertical wave orbital velocities ...

Understanding The Influence Of Nonlinear Seas On Wind Generated Waves, Taylor L. Bailey

Electronic Theses and Dissertations

An understanding of the influence of wind of the surface on irregular waves is important for improving ocean forecasting models. While many studies have investigated the phenomenon of wind wave suppression on the surface of mechanically generated waves in the laboratory, few studies have investigated the occurrence of this phenomenon for irregular waves. Chen and Belcher (2000) developed the first model to predict the suppression of wind waves as a function of the steepness of the long wave on which they travel. The Chen and Belcher (2000) model however, was only validated using monochromatic waves, not irregular waves, which are ...

Fabrication Of Silicon Microneedles For Dermal Interstitial Fluid Extraction In Human Subjects, Caleb A. Berry

Electronic Theses and Dissertations

The goal of this project is to design and develop a fabrication process for silicon microneedle arrays to extract dermal interstitial fluid (ISF) from human skin. ISF is a cell- free, living tissue medium that is known to contain many of the same, clinical biomarkers of general health, stress response and immune status as in blood. However, a significant barrier to adoption of ISF as a diagnostic matrix is the lack of a rapid, minimally invasive method of access and collection for analysis. Microfabricated chips containing arrays of microneedles that can rapidly and painlessly access and collect dermal ISF for ...

Methods For Mass Data Acquisition Of Whiskey Webs., Adam D. Carrithers

Electronic Theses and Dissertations

Whiskey webs are a recently discovered phenomenon in which the monolayer collapse during evaporation of diluted American whiskey results in self-assembled, web-like structures. It was found that the pattern of weblike structures were unique between different American whiskey products. It is desirable to use these unique patterns as a “fingerprint” which can be used to identify whiskeys, their chemical constituents, and perhaps even counterfeits. In pursuit of identifying whiskey products based on their web pattern, it is necessary to have a large database of samples imaged for each product. The device discussed herein is the realization of an apparatus capable ...

Characterization Of Photoacoustic Flow Cytometry Signals, Craig Benzinger

Electronic Theses and Dissertations

Photoacoustic flow cytometry has been utilized to clinically determine the presence of melanoma circulating tumor cells (CTCs). Further investigation was conducted into the morphology of detection signals and how they could be manipulated to allow for further classification. Novel features were extracted from waveforms that appear to have strong classification ability. Neural networks were also used to determine classification potential and the creation of feature mapping for future unsupervised classification. Detections were expanded from single waves to a time dependent multiwave event. Waveforms were also determined to be of non-parametric distribution, allowing for classification by neural network but not allowing ...

Identification Of Human Adrenal Carcinoma Cells Using Photoacoustic Flow Cytometry, Alexis Stahl

Electronic Theses and Dissertations

With consistently high mortality rates in patients with adrenal cancer, lack of early detection and diagnosis are an ever increasing problem in fighting the deadly disease. Currently, very few patients are diagnosed with adrenal cancer within the early stages due to the absence of symptoms until large tumors are formed, which is in most cases is fatal. Because of this, early detection equipment is crucial to optimizing the survival rate in patients. We studied the absorbance wavelength of human adrenal carcinoma cells, as well as the minimum cell concentration needed in samples using photoacoustic flow cytometry (PAFC). PAFC generates ultrasonic ...

Pilot Study Exploring The Effect Of Targeted Cox-2 Inhibition In Macrophages Responding To Neuronal Injury; Promoting Enhanced Axonal Regeneration, Alyssa Brauckmann

Electronic Theses and Dissertations

Celecoxib nanoemulsion (CXB-NE) has been developed as a macrophage targeted analgesics by Dr. Janjic and her team at Duquesne University, (Janjic et al, 2018; Liu et al, 2020; Saleem et al, 2019b; Vasudeva et al, 2014). The CXB-NE nanoemulsion carrying a Nonsteroidal Anti-inflammatory (NSAID) inhibitor of COX-2 activity result in a reduction in PGE2 expression in macrophages. Using CXB-NE in rats that have peripheral nerve injury constricting the sciatic nerve relieves hypersensitivity, a pain-like behavior. The treatment also decreases inflammation associated with this chronic constriction injury (Janjic et al, 2018; Saleem et al, 2019b; Stevens et al, 2019). In this ...

Understanding Latina Undergraduate Engineering Student Persistence, Yarissa I. Ortiz-Vidal

Electronic Theses and Dissertations

In summary, this study focused on understanding the persistence of 20 Latina undergraduate engineering students enrolled at two public four-year Hispanic Serving Institutions. Key findings in this study showed that in order to contribute to their own persistence in engineering majors these Latina students activated their community cultural wealth: (a) not only to resist different forms of oppression, but also to thrive and excel in academic settings, (b) to take control of difficult and challenging experiences, (c) to take/receive knowledge from others, but also to give/share their knowledge (cyclical tendencies of CCW), (d) as well as revealing that ...

Labview Improvements And Equipment Redesign Of Unit Operations Distillation Column, Madalyn S Wead

Electronic Theses and Dissertations

Unit Operations labs are important tools to provide hands-on learning with various chemical processes. The distillation lab experiment allows students to connect equations and definitions from textbooks to the physical processes of distillation as they occur. LabVIEW was the software development tool used to create a program to control the distillation column from startup to shutdown. Improvements were made to both the distillation process equipment and the LabVIEW code to create a more interactive lab experience, enhance students’ conceptual understanding of distillation, and prepare students for their future career as chemical engineers.

Equipment addressed included non-linear valves, malfunctioning temperature and ...

Mathematical Characterization Of A Microfluidic Ultrasound Driven Transfection Device., Chris J. Holton

Electronic Theses and Dissertations

The objective of this thesis is to develop a mathematical model characterizing the behavior of a microfluidic sonoporation device in order to understand how standing wave conditions influence molecular delivery to cells and determine whether the model predicts device performance. A prior model based on an ultrasonic separation cell that uses standing waves to separate particles is adapted for translation to the microfluidic device. This study generates data on acoustic pressure profiles across the cell as well as identifying optimal driving frequencies. This model is validated and the equations and methods for developing this model are translated to the microfluidic ...