Engineering Commons^™

Numerical Study Of Laryngeal Control Of Phonation Using Realistic Finite Element Models Of A Canine Larynx, Biao Geng

Electronic Theses and Dissertations

While many may take it for granted, the human voice is an incredible feat. An average person can produce a great variety of voices and change voice characteristics agilely even without formal training. Last several decades of research has established that the production of voice is largely a mechanical process: i.e., the sustained vibration of the vocal folds driven by the glottal air flow. Since one only has a single pair of vocal folds, the versatility comes with the ability to change the mechanical status of the vocal folds, including vocal fold length and thickness, tension, and level of adduction, …

Detecting Viral Particles In Vitro Using Photoacoustic Flow Cytometry, Anie-Pier Samson

Electronic Theses and Dissertations

The Covid-19 pandemic is a powerful example of just how damaging the rapid spread of an unknown virus can be. Viruses have the ability to spread rapidly amongst individuals if not treated and controlled. The first key step towards treatment is the timely and specific diagnosis of the virus causing the infection. An innovative method for the rapid detection of viral particles in solution consists of tagging the viral particles paired with using photoacoustic flow cytometry to irradiate the particles and get a signal. The high affinity of Streptavidin for Biotin can be used to bind Streptavidin-coated microspheres to biotinylated …

Real-Time Monitoring Of Cell Death Progress Using Capacitance Spectroscopy, Suyang Wu

Electronic Theses and Dissertations

Biologics, including the monoclonal antibody (mAb), has experienced rapid development in the last decade. However, the price of biologics is often prohibitively high because of the low process efficiency. Delaying the inevitable cell death improves the productivity of upstream bioprocessing, whose success relies on monitoring the cell death onset that indicates the timing for preventive actions.

This study proposes to develop a real-time monitoring model that quantifies the dying cell percentage in lab-scale bioreactors using capacitance spectroscopy. The capacitance spectroscopy contains cell death-related information due to various physical properties changes during the cell death process, e.g., cytoplasmic conductivity change. The …

Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari

Electronic Theses and Dissertations

Extrusion-based 3D printing of thermoplastic polymer composites manufactures parts that have nonhomogenous, orthotropic, and process-dependent macro-scale material properties. As a part of the dissertation, research works were carried out to: • improve the interlayer mechanical properties and reduce the orthotropy, • use experimentally homogenized orthotropic material properties to numerically model the mechanical behavior of the non-homogenous orthotropic 3D printed parts, • create an efficient numerical thermal model to predict the process-dependent thermal history of the 3D printed part, and • aid the manufacturing process by selecting a suitable set of processing parameters based on a simplified sequentially coupled thermomechanical model. …

Investigation Of Mass-Manufactured Nanostructured Material For Contamination Detection Via Structural Color Analysis, Oisin Biswas

Electronic Theses and Dissertations

The spread of the SARS-CoV-2 virus has underlined the importance of monitoring surface contamination of infectious elements on commonly used surfaces. Current monitoring methods of surfaces are both lengthy and expensive. The work in this project took advantage of the optical phenomenon of structural color to develop a rapid, low-cost, and contactless method of surface contamination detection. To accomplish this, a mass-produced material imprinted with a nanostructured pattern capable of exhibiting this structural color phenomenon was used. Structural color, or the bands of color that appear as different wavelengths of light reflect off a textured surface, can vary as a …

Digital Design And Thermomechanical Process Simulation For 3d Printing With Abs And Soyhull Fibers Reinforced Abs Composites., Saleh Khanjar

Electronic Theses and Dissertations

Recent demonstrations with fused filament fabrication (FFF) 3D printing have shown to produce prototypes as well as production components. Additionally, due to the FFF process platforms being low-cost and readily available there has been a high-demand to produce on-demand parts for various applications in automotive, in-space manufacturing and electronic industries. However, current limitations such as limited availability of advanced composites materials, and guidelines for design-for-manufacturing make the process prone to trial-and-error experiments both at the materials development, product design and manufacturing stage. In this work, new thermomechanical process simulations platform, Digimat-AM has been evaluated to address and demonstrate digital design …

Modeling Driver Distraction Mechanism And Its Safety Impact In Automated Vehicle Environment., Song Wang

Electronic Theses and Dissertations

Automated Vehicle (AV) technology expects to enhance driving safety by eliminating human errors. However, driver distraction still exists under automated driving. The Society of Automotive Engineers (SAE) has defined six levels of driving automation from Level 0~5. Until achieving Level 5, human drivers are still needed. Therefore, the Human-Vehicle Interaction (HVI) necessarily diverts a driver’s attention away from driving. Existing research mainly focused on quantifying distraction in human-operated vehicles rather than in the AV environment. It causes a lack of knowledge on how AV distraction can be detected, quantified, and understood. Moreover, existing research in exploring AV distraction has mainly …

Atomistic Investigation Of Phase Stability And Sodium Ion Conduction In Sulfide Electrolytes., Sabina Zakhidovna Chertmanova

Electronic Theses and Dissertations

In this thesis, we employ a combination of density functional theory (DFT) calculations, and ab initio molecular dynamics (AIMD) simulations to identify the effect of chemical doping on (a) thermodynamic phase stability, and (b) Na-ion conduction in Na₃SbS₄ (NSS) solid-state electrolytes. We found that (a) Se doped electrolytes, namely, Na₃SbS_exS_4-x undergo a tetragonal-to-cubic structural phase transition at x > 3 (Se-rich), and (b) the size, valence, and electronegativity of chemical dopants that substitute Na in Na₃SbS₄ have a cumulative profound impact on Na-ion conductivity. Specifically, substituting Na with higher valence …

Hybrid Structural Health Monitoring Using Data-Driven Modal Analysis And Model-Based Bayesian Inference., Jice Zeng

Electronic Theses and Dissertations

Civil infrastructures that are valuable assets for the public and owners must be adequately and periodically maintained to guarantee safety, continuous service, and avoid economic losses. Vibration-based structural health monitoring (VBSHM) has been a significant tool to assess the structural performance of civil infrastructures over the last decades. Challenges in VBSHM exist in two aspects: operational modal analysis (OMA) and Finite element model updating (FEMU). The former aims to extract natural frequency, damping ratio, and mode shapes using vibrational data under normal operation; the latter focuses on minimizing the discrepancies between measurements and model prediction. The main impediments to real-world …

Techno-Economics And Life Cycle Analysis Of Upgrading Woody Biomass To Diesel Blendstock, Aysan Najd Mazhar

Electronic Theses and Dissertations

Woody biomass conversion to transportation fuels have been developed as alternatives to fossil fuel production to reduce greenhouse gas emissions and to increase energy security. Fast pyrolysis, a thermochemical technology, has the potential to offer high efficiencies to produce liquid transportation fuels from woody biomass. Fast pyrolysis involves rapid heating of biomass particles in the absence of air at approximately 500°C and results in non-condensable gases, bio-oil (pyrolysis oil), and char as products. The pyrolysis oil can be upgraded via integrated mild hydrogenation and etherification processes to a high energy density fuel that can be blended with diesel for transportation …

Gradient Generating Microfluidic Coculture System For Disease Modeling And Neural Development, Phaneendra Chennampally

Electronic Theses and Dissertations

Cellular microenvironment or cell niche plays an important role in developmental biology and disease pathophysiology. Physical or chemical signals in microenvironment drive the cellular activity. These signaling molecules are generated from the surrounding cells/tissues as part of intercellular communication; a fundamental property of a cell. Dynamic profile of these signaling molecules in the microenvironment plays a pivotal role in transfer of molecular information from cell to cell in disease proliferation or fate determination. Recapitulating these signaling cues in an in vitro study is difficult to achieve using standard cell culture techniques. However microfluidic systems are capable of addressing these issues, …

Comparison Between Cpu And Gpu For Parallel Implementation For A Neural Network Model Using Tensorflow And A Big Dataset, Intisar Alkaabwi

Electronic Theses and Dissertations

Machine learning is a rapidly growing field that has become more common of late. Because of the demanding computational usage of machine learning, this field has many dimensions needing research. TensorFlow has been developed to deal with and analyze neural networks computation. In particular, TensorFlow is often used in one of the machine learning branches and is called deep learning. This work discusses the performance of a deep learning model to train a very large dataset with TensorFlow. It compares performance when the run happens on CPUs and on GPUs regarding the run time and speed. The run time is …

Computer Modeling Using The Finite-Difference Time-Domain (Fdtd) Method For Electromagnetic Wave Propagation, Atheer A. Oufi

Electronic Theses and Dissertations

The Finite-Difference Time-Domain (FDTD) technique is a numerical analysis modeling method to find the solutions of the partial derivatives in Maxwell’s equations to electromagnetic problems. In FDTD the electrical and magnetic fields components staggered in time and space by a method developed by Yee. The approximation of the solutions can be found using a set of updated equations.

In every simulation that utilizes the FDTD method, the factors of time and memory size are the two significant considerations. This study focused on reducing the computation time, as the time required to time-march the components of the electrical and magnetic fields …

Design, Quantification, And Strengthening Of Interface Interaction Between Aramid Fibers And Polymer Matrix, Karrar Al-Quraishi

Electronic Theses and Dissertations

Composites reinforced by aramid fibers may suffer poor interface interactions during mechanical loading due to the smooth and chemically inert surface of the fibers. Three main strategies have been used to improve the interface shear strength (IFSS) including increasing surface roughness, enriching fiber surface with functional groups, and surface coating with ceramic particles. Plasma treatment is usually employed to functionalize and roughen surface of the fibers, leading to strengthening of the interface between the fibers and polymer matrix. A concern for fibers reinforced polymers is that the IFSS would significantly decrease once the composite is exposed to elevated temperatures. To …

Determination Of Bridge Behavior Through Live-Load Testing And Advanced Numerical Analysis, Andrew Schanck

Electronic Theses and Dissertations

Bridges represent critical nodes in the United States’ transportation network, and an accurate understanding of their strength and durability is paramount to their continued use to transport people and goods. Traditionally, bridge assessment has been conducted through conventional beam-line analysis of isolated bridge components as specified by the American Association of State Highway and Transportation Officials (AASHTO). Although this method is reasonable for relatively new structures whose behavior are well understood, it can lead to significant over-conservative estimates of live-load capacity for older structures and for new types of structure for which design bases are still being developed. For such …

Developing A Process To Select B2b Target Markets With A Focus On Siemens Simatic Controllers, Eva Limbrunner

Electronic Theses and Dissertations

The process to identify and describe target markets can be challenging for marketers due to the complexity of B2B markets and industrial products. This case-based study aims to bridge the gap between theory and praxis by developing a process to determine target markets for Siemens SIMATIC controllers, which are highly technological products designed for process control and used in industrial applications. The author conducted a literature review to investigate the current understanding of B2B market segmentation and target marketing and collected qualitative data from Siemens. This study defines segmentation variables leveraging segmentation models as a foundation to build and describe …

Materials And Process Design For Ceramic Fused Filament Fabrication (Cf3) Of Hydroxyapatite., Kavish Sudan

Electronic Theses and Dissertations

Ceramic fused filament fabrication (CF3) enables the fabrication of highly customizable ceramic parts at relatively lower costs compared to other AM technologies. Advanced ceramics, having specific or niche applications, call for a high level of accuracy to meet the performance requirements. For achieving the desired level of accuracy in any manufacturing process, it is important to know the effect of involved parameters at different stages of fabrication. CF3 has been around for a while but there has been a severe lack of literature dealing with understanding the effect of process parameters on the final part properties. In this study, Hydroxyapatite …

Scalable Synthesis Of Alumina Nanowires By Wet Chemical Method., Luis N Moreno

Electronic Theses and Dissertations

To satisfy an increasing demand for large-scale processes for producing alumina nanomaterials, a wet chemical method was evaluated. A potassium salt precursor was combined with aluminum to produce alumina – based nanowires. Compared with current methods such as thermal oxidation, sol-gel, and laser ablation, this method is highly scalable due to relatively low energy requirements and the ability to carry out the primary reaction under ambient conditions. The nanowire samples were evaluated using SEM, XRD, BET, and TEM to confirm morphology, phases present, and surface area. A porous nanowire structure was confirmed which has a BET surface area of 324.6 …

Synthesis, Crystal Structure And Ionic Conductivity Of Ruddlesden-Popper Oxide Materials: Effects Of Ionic Radii And Defects On Lithium-Ionic Conductivity., Selorm Joy Fanah

Electronic Theses and Dissertations

Layered perovskite oxides of the Ruddlesden-Popper (RP) type structure can be good lithium-ion conductors for solid electrolyte applications in all-solid-state batteries, due to the large gap separating octahedral layers which can be useful pathways for Li-ion conduction. However, little work has been done on their lithium-ion transport properties in these materials despite their interesting structural properties. This work highlights the synthesis and study of the ionic conductivities in a series of n = 2 and 3 Ruddlesden-Popper oxides, as part of an ongoing investigation in search of alternative solid electrolyte materials. Several different strategies were employed for the enhancement of …

Towards Long Term Colloid Suspension In A Vertically Rotated System., Md Mahmudur Rahman

Electronic Theses and Dissertations

Within a colloidal suspension gravity may compromise the observation of governing physical interactions, especially those that are weak and/or take significant time to develop. Conducting the experiment in a long-term microgravity environment is a viable option to negate gravitational effects, though significant resources are required to do so. While it may not be possible to simulate long-term microgravity terrestrially, particles can resist quick sedimentation in a confined suspension system rotating vertically with appropriate rotation speed. The goal of the investigation is to demonstrate the existence of long-term particle suspension regime for a certain colloidal suspension while characterizing colloidal behavior due …

Collaborative Human-Machine Interfaces For Mobile Manipulators., Shamsudeen Olawale Abubakar

Electronic Theses and Dissertations

The use of mobile manipulators in service industries as both agents in physical Human Robot Interaction (pHRI) and for social interactions has been on the increase in recent times due to necessities like compensating for workforce shortages and enabling safer and more efficient operations amongst other reasons. Collaborative robots, or co-bots, are robots that are developed for use with human interaction through direct contact or close proximity in a shared space with the human users. The work presented in this dissertation focuses on the design, implementation and analysis of components for the next-generation collaborative human machine interfaces (CHMI) needed for …

Drone Location And Scheduling Problems In Humanitarian Logistics., Zabih Ghelichi

Electronic Theses and Dissertations

Unmanned Aerial Vehicles (UAVs), commonly referred to as drones, are a promising technology for the last-mile delivery of medical and aid items in humanitarian logistics. In emergency scenarios, like disasters, where transportation networks are destroyed and people are stranded, drones can accelerate the delivery of urgently needed items, e.g., food and water, insulin shots and blood pressure pills, to those trapped in the disaster-affected areas. Drones can also provide logistics services in many non-emergency situations by delivering medical items, e.g., vaccine shots and lab specimens, to remote communities and hard-to-access locations. The contribution of using UAVs goes beyond merely having …

Lung Nodules Identification In Ct Scans Using Multiple Instance Learning., Wiem Safta

Electronic Theses and Dissertations

Computer Aided Diagnosis (CAD) systems for lung nodules diagnosis aim to classify nodules into benign or malignant based on images obtained from diverse imaging modalities such as Computer Tomography (CT). Automated CAD systems are important in medical domain applications as they assist radiologists in the time-consuming and labor-intensive diagnosis process. However, most available methods require a large collection of nodules that are segmented and annotated by radiologists. This process is labor-intensive and hard to scale to very large datasets. More recently, some CAD systems that are based on deep learning have emerged. These algorithms do not require the nodules to …

Additive Manufacturing Using Robotic Manipulators, Fdm, And Aerosol Jet Printers., Alexander Curry

Electronic Theses and Dissertations

Additive manufacturing has created countless new opportunities for fabrication of devices in the past few years. Advances in additive manufacturing continue to change the way that many devices are fabricated by simplifying processes and often lowering cost. Fused deposition modeling (FDM) is the most common form of 3D printing. It is a well-developed process that can print various plastic materials into three-dimensional structures. This technology is used in a lot of industries for rapid prototyping and sometimes small batch manufacturing. It is very inexpensive, and a prototype can be created in a few hours, rather than days. This is useful …

An Investigation Into Energy-Material Properties Interaction In Additive Manufacturing Of Polymers., Pu Han

Electronic Theses and Dissertations

Additive manufacturing (AM), known as three-dimensional (3D) printing, is a fabrication process to build 3D objects layer by layer based on computer aided design (CAD) model or digital 3D model. Fused filament fabrication (FFF) has become a preferred method for additive manufacturing due to its cost-effectiveness and flexibility. However, the parts built using FFF process suffer from lower mechanical strength compared to that fabricated using traditional method and rough surface finish. With this motivation, this dissertation aims to develop and implement a novel in-process laser assisted technique on FFF to heal the microstructure of FFF built objects by enhancing reptation …

Coal Fly Ash Beneficiation For Reuse And Removal Of Boron, Cadmium, Chromium, Copper, And Selenium In Wastewater Treatment., Joseph E. Cahill

Electronic Theses and Dissertations

New regulations on coal-fired power plants make previously used wastewater treatment methods aimed to remove heavy metals obsolete. Therefore, there has been increased interest and investment into new technologies to treat coal-fired power plants effluent in the past few years. Traditionally, heavy metal removal technologies have been broken into three categories: physical, chemical or biological. However, with new regulations, each category by itself does not offer an ideal solution to removing acceptable concentrations of heavy metals found in the effluents at the coal-fired power plants. Here we report a novel proof-of-concept utilizing adsorption through ion-exchange/co-precipitation - chemical and physical - …

An Introductory Study Of Coal Fly Ash Enhancement For Heavy Metal Removal In Wastewater Treatment., Samuel T. Romes

Electronic Theses and Dissertations

Coal Combustion Products are the materials that remain after pulverized coal is burned to generate electricity. The fine portion, fly ash, has many re-use capabilities across various industries. Most recent data shows that approximately 60% of fly ash produced in the United States was used with the largest re-use being concrete additives. This work aims to enhance fly ash via hydrothermal treatment in order to expand the re-use capabilities of the material. These materials were tested as adsorbents for heavy metal removal from wastewater samples. The metals tested for removal were Copper (II) Acetate, Cadmium Chloride, Boric Acid, Sodium Selenite, …

Computational Modeling Of 3d-Printed Lactobacillus-Antibiotic Scaffolds For Bacterial Vaginosis., Veeresh P. Rai

Electronic Theses and Dissertations

The standard treatment for bacterial vaginosis (BV) is currently antibiotics, such as metronidazole, clindamycin, or tinidazole. These antibiotics are highly effective in getting rid of bacteria in the female reproductive tract (FRT); however, there are some bacteria that provide benefits to the FRT which also get expunged. While there are many strains of bacteria that play a beneficial role in the FRT, lactobacilli are among the most important. These bacteria are responsible for maintaining a healthy environment in the FRT via pH regulation by lactic acid metabolism. Antibiotics eliminate all bacteria from an environment, including lactobacilli, and as a result, …

Design Of A 300cm2 Pemfc Stack With Force And Cfd Simulation To Optimize Flow Channels, Gasket Design, And Clamping Forces., Robert M. Ench

Electronic Theses and Dissertations

Proton exchange membrane fuel cells are important to the future of green energy as hydrogen can be made with green technologies and store energy for later use. Fuel cells can efficiently convert the hydrogen to electricity as needed. This study uses Solidworks simulation to make design improvements to the fuel cell before the prototype build stage of testing; this saves money and time by reducing the prototype builds needed.

In this study, a multi-channel serpentine design with two outlets versus a single outlet is evaluated using CFD to investigate pressure drop. Lower pressure drops are desirable as less energy input …

Solvent Engineering Of Molybdenum Disulfide Electrocatalyst For Hydrogen Evolution., Robert Carl Spalding

Electronic Theses and Dissertations

Energy is at an exponentially growing demand, and to keep up with these demands new technologies for renewable energy have received increased attention. Hydrogen plays a vital role in water electrolysis and fuel cells, as the hydrogen evolution reaction (HER) is the main step water splitting process. Most of the current electrocatalysts for HER are dominated by platinum and other precious metals due to their low over-potential and small Tafel slope, however, they are extremely costly. For this reason, cost-effective non-precious metal catalysts must be developed. Transition metal dichalcogenides, such as molybdenum disulfide (MoS2), are abundant and have recently shown …