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Old Dominion University

2021

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Full-Text Articles in Engineering

Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone Dec 2021

Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky Dec 2021

Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky

Mechanical & Aerospace Engineering Theses & Dissertations

The aim of this work is to study the effect of post-processing on additive manufactured (AM) continuous carbon fiber reinforced plastics (CFRPs) performance. As-printed AM CFRPs do not perform as well as conventionally manufactured CFRPs with the same composition. Possible improvements to AM CFRP performance include annealing and applying uniaxial pressure with elevated temperature. Samples were subjected to pressure and temperature treatments and annealing at a constant temperature. Treated materials were subjected to three-point bending tests, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to characterize and assess sample performance. Results were assessed for flexural strength, …


What Is An Effective Way To Measure Arterial Demand When It Exceeds Capacity?, Mecit Cetin, Hong Yang, Kun Xie, Giridhar Kattepogu, Behrouz Salahshour Dec 2021

What Is An Effective Way To Measure Arterial Demand When It Exceeds Capacity?, Mecit Cetin, Hong Yang, Kun Xie, Giridhar Kattepogu, Behrouz Salahshour

Civil & Environmental Engineering Faculty Publications

This project focused on developing and evaluating methods for estimating demand volume for oversaturated corridors. Measuring demand directly with vehicle sensors is not possible when demand is larger than capacity for an extended period, as the queue grows beyond the sensor, and the flow measurements at a given point cannot exceed the capacity of the section. The main objective of the study was to identify and develop methods that could be implemented in practice based on readily available data. To this end, two methods were proposed: an innovative method based on shockwave theory; and the volume delay function adapted from …


Towards Characterizing Adversarial Opportunity And Behavior In Critical Infrastructure Network, Md Sharif Ullah Dec 2021

Towards Characterizing Adversarial Opportunity And Behavior In Critical Infrastructure Network, Md Sharif Ullah

Electrical & Computer Engineering Theses & Dissertations

The growth of information and communication technology is constantly revolutionizing various domains, e.g., energy utility systems, healthcare, the internet of things, etc. This inception of widespread cyber technology enables reliability and first operability of the system, yet simultaneously imposed a risk of significant impact due to disruption of safe and secure operation. The attack surface is expanding, creating a cyber exposure gap which indicates a higher threat landscape and increased risk of compromise. Motivated by this increased threat exposure, this dissertation investigates the attack surface as a static and dynamic indicator of adversary propagation, seeking an efficient modeling paradigm to …


Lean Application: An Assessment Of 5s On Employee Attitudes And Productivity, Nickolaos Dimitrios Karvounis Dec 2021

Lean Application: An Assessment Of 5s On Employee Attitudes And Productivity, Nickolaos Dimitrios Karvounis

STEMPS Theses & Dissertations

This study examines the effect of the implementation of 5S on employee attitudes and productivity in an Asian based facility of a global manufacturing company. Utilizing an assessment of the 5S implementation in various areas of the facility and organizational performance data for each of those areas, a non-experimental, causal comparative approach is used to analyze the impact. The study concluded that statistically significant improvements from the implementation of 5S were found both in quality and product cost for this facility; however, the study also found statistical significance where the implementation of 5S led to a decrease in performance and …


Protection And Disturbance Mitigation Of Next Generation Shipboard Power Systems, Marounfa Djibo Dec 2021

Protection And Disturbance Mitigation Of Next Generation Shipboard Power Systems, Marounfa Djibo

Electrical & Computer Engineering Theses & Dissertations

Today, thanks to modern advances mainly in the power electronics field, megawatt-level electric drives and magnetic levitation are being integrated into the marine power grids. These technologies operate based on Direct Current (DC) power which require Alternating Current (AC) to DC conversion within the current grid. Medium-voltage Direct Current (MVDC) and Flywheel Energy Storage Systems (FESS) are the next state-of-the-art technologies that researchers are leaning on to produce, convert, store, and distribute power with improved power quality, reliability, and flexibility. On the other hand, with the extensive integration of high-frequency power electronic converters, system stability analysis and the true system …


A Testing And Experimenting Environment For Microscopic Traffic Simulation Utilizing Virtual Reality And Augmented Reality, Mahmud Hasan Dec 2021

A Testing And Experimenting Environment For Microscopic Traffic Simulation Utilizing Virtual Reality And Augmented Reality, Mahmud Hasan

Computational Modeling & Simulation Engineering Theses & Dissertations

Microscopic traffic simulation (MTS) is the emulation of real-world traffic movements in a virtual environment with various traffic entities. Typically, the movements of the vehicles in MTS follow some predefined algorithms, e.g., car-following models, lane changing models, etc. Moreover, existing MTS models only provide a limited capability of two- and/or three-dimensional displays that often restrict the user’s viewpoint to a flat screen. Their downscaled scenes neither provide a realistic representation of the environment nor allow different users to simultaneously experience or interact with the simulation model from different perspectives. These limitations neither allow the traffic engineers to effectively disseminate their …


Generation, Analysis, And Evaluation Of Patient-Specific, Osteoligamentous, Spine Meshes, Austin R. Tapp Dec 2021

Generation, Analysis, And Evaluation Of Patient-Specific, Osteoligamentous, Spine Meshes, Austin R. Tapp

Biomedical Engineering Theses & Dissertations

Scoliosis, an abnormal curvature of the spine, is traditionally corrected with bracing treatments or by a highly invasive posterior spinal fusion (PSF) operation. These correction strategies are constrained by current imaging modalities, which fail to elucidate the soft tissue anatomy that is known to play a critical role in spinal stiffness and overall structure. Osteoligamentous segmentations of the spinal column offer a foundation for downstream finite element (FE) studies seeking to optimize bracing treatments or determine ideal surgical approaches.

This thesis presents methods for automatically and semi-automatically segmenting vertebrae and surrounding soft tissues of the spinal column using X-ray computed …


The Investigations Of Nps Modulated Immunity And Immunometabolism, Brittney Leigh Ruedlinger Dec 2021

The Investigations Of Nps Modulated Immunity And Immunometabolism, Brittney Leigh Ruedlinger

Biomedical Sciences Theses & Dissertations

Cancers remain in the top noncommunicable diseases responsible for premature mortality. The heterogeneity among cancers and within tumors makes treating them ever more challenging. Our misfortune for developing cures is mocked by cancer, with the lowest probability of success (PoS) through clinical trials and FDA approval. At the basic level, there are generally two broad gaps impeding cancer eradication: the unidentified shared mechanism(s) exploited by all cancers and the therapeutic approach to intervene. Nanosecond pulse stimulation (NPS) offers a unique approach since its broad impacts intersect those often hijacked by oncogenesis. Metabolic pathways, known for dysfunctions among cancers, share a …


Spatiotemporal Variations Of Precipitation And Climate-Resilient Structure Design In Virginia, Xiaomin Yang Dec 2021

Spatiotemporal Variations Of Precipitation And Climate-Resilient Structure Design In Virginia, Xiaomin Yang

Civil & Environmental Engineering Theses & Dissertations

How to consider effects of climate change on the design and management of hydrology related infrastructure is crucial but remains a challenge for sustaining resilient society. To address this challenge, existing hydrologic design procedures may need to be revised and/or redeveloped to take into account the precipitation non-stationarity resulting from climate change. Using the state of Virginia as a testbed and advanced statistical techniques such as nonparametric test, spatial autocorrelation, linear regression, distribution fitting, and spatial interpolation, this dissertation developed an innovative framework to detect the historical spatiotemporal variations of various precipitation characteristics, namely maximum precipitation intensity, precipitation amount, simple …


Data-Driven Operational And Safety Analysis Of Emerging Shared Electric Scooter Systems, Qingyu Ma Dec 2021

Data-Driven Operational And Safety Analysis Of Emerging Shared Electric Scooter Systems, Qingyu Ma

Computational Modeling & Simulation Engineering Theses & Dissertations

The rapid rise of shared electric scooter (E-Scooter) systems offers many urban areas a new micro-mobility solution. The portable and flexible characteristics have made E-Scooters a competitive mode for short-distance trips. Compared to other modes such as bikes, E-Scooters allow riders to freely ride on different facilities such as streets, sidewalks, and bike lanes. However, sharing lanes with vehicles and other users tends to cause safety issues for riding E-Scooters. Conventional methods are often not applicable for analyzing such safety issues because well-archived historical crash records are not commonly available for emerging E-Scooters.

Perceiving the growth of such a micro-mobility …


Synthesis And Characterization Of 4,6-Protected Glucosamine Derivatives And Branched Glycoconjugates, Jonathan Bietsch Dec 2021

Synthesis And Characterization Of 4,6-Protected Glucosamine Derivatives And Branched Glycoconjugates, Jonathan Bietsch

Chemistry & Biochemistry Theses & Dissertations

Low molecular weight gelators (LMWGs) are small molecules that self-assemble in appropriate solvents to form three dimensional networks that immobilize the solvent, creating a supramolecular gel. The self-assembly of LMWGs occurs through non-covalent interactions such as hydrogen bonding, aromatic interactions, donor-acceptor interactions, Van der Waals interactions, hydrophobic forces, halogen bonding, etc. Due to self-assembly occurring through reversible non-covalent interactions, supramolecular gels can undergo a gel to solution transformation. Because of this, these materials can be sensitive to external stimuli such as temperature changes, pH changes, and other stimuli that effect non-covalent interactions. This makes the synthesis of LMWG’s an appealing …


Hydrothermal Processes For Extraction And Conversion Of Biomass To Produce Biofuels And Value-Added Products, Anuj Hemant Thakkar Dec 2021

Hydrothermal Processes For Extraction And Conversion Of Biomass To Produce Biofuels And Value-Added Products, Anuj Hemant Thakkar

Civil & Environmental Engineering Theses & Dissertations

An integrated biorefinery approach based on subcritical hydrothermal processes was developed to maximize utilization of biomass components by producing multiple products. Biomass from various sources like agricultural waste (lignocellulose), food waste (spent yeast), and dedicated cultivation (micro-algae) was used in this research.

Corn stover (agricultural waste) was hydrothermally pretreated to remove lignin and xylan while preserving most of the glucan. The pretreated corn stover was utilized to produce levulinic acid (thermochemically) and fermentable sugars (biochemically). The solid residue generated during levulinic acid production was utilized to produce biocarbon electrode material. The results generated from the experiments were used for designing …


Subtalar Joint Definition In Biomechanical Models, Julia Noginova Dec 2021

Subtalar Joint Definition In Biomechanical Models, Julia Noginova

Biomedical Engineering Theses & Dissertations

The effect of including a subtalar joint in a dynamic musculoskeletal model has not been fully explored or validated. The subtalar joint is often modeled as a one DOF hinge with the tri-planar axis defined as a combination of inclination and deviation angles measured from the ground and midline of the foot, respectively. The overall purposes of this dissertation were to explore how the inclusion of the subtalar joint and the definition of origin location and axis orientation affect the kinematics, joint kinetics, and muscle activations of the knee, ankle, and subtalar joint during dynamic tasks of walking and running …


Tunable Compressive Mechanical Behavior Of Ice-Templated Materials, Sashanka Akurati Dec 2021

Tunable Compressive Mechanical Behavior Of Ice-Templated Materials, Sashanka Akurati

Mechanical & Aerospace Engineering Theses & Dissertations

The inherent hierarchical microstructural organization in natural materials is responsible for their excellent mechanical properties beyond that predicted by the simple rule-of-mixtures. Further exhibit synergy between strength and toughness, otherwise mutually exclusive in brittle materials. Conventional processing methods are unable to replicate hierarchical microstructures in engineering ceramics akin to that observed in natural materials. Ice-templating has emerged as a potential technique to fabricate bioinspired hierarchical materials. This process involves simultaneous unidirectional solidification and phase segregation of aqueous suspensions. Ice-templated porous ceramic materials have received significant attention for overcoming several limitations of conventional ceramic foams currently used in numerous engineering applications. …


Integrated Processing Of Municipal Solid Waste For Maximizing Waste Reduction, Carbon Recovery And Fuel Production, Kameron J. King Dec 2021

Integrated Processing Of Municipal Solid Waste For Maximizing Waste Reduction, Carbon Recovery And Fuel Production, Kameron J. King

Civil & Environmental Engineering Theses & Dissertations

Nationally and internationally, waste generation is increasing and along with it negative environmental impacts. Many people think waste ends at disposal; however, environmental impacts have already begun. Unfortunately, 50% of waste ends up in a landfill which is the third largest source of human related methane emissions and a leading cause of global climate change. This study investigated a novel waste management strategy in hopes of mitigating negative environmental effects caused by conventional waste management practices. The novelty of the study lies in the development of an integrated method of hydrothermal carbonization and an anaerobic digestion (HTC + AD) process …


Joint Linear And Nonlinear Computation With Data Encryption For Efficient Privacy-Preserving Deep Learning, Qiao Zhang Dec 2021

Joint Linear And Nonlinear Computation With Data Encryption For Efficient Privacy-Preserving Deep Learning, Qiao Zhang

Electrical & Computer Engineering Theses & Dissertations

Deep Learning (DL) has shown unrivalled performance in many applications such as image classification, speech recognition, anomalous detection, and business analytics. While end users and enterprises own enormous data, DL talents and computing power are mostly gathered in technology giants having cloud servers. Thus, data owners, i.e., the clients, are motivated to outsource their data, along with computationally-intensive tasks, to the server in order to leverage the server’s abundant computation resources and DL talents for developing cost-effective DL solutions. However, trust is required between the server and the client to finish the computation tasks (e.g., conducting inference for the newly-input …


Assessment Of The Hydrograv® Adapt Variable Height Secondary Clarifier Inlet At Hrsd Nansemond Treatment Plant, Matthew Poe Dec 2021

Assessment Of The Hydrograv® Adapt Variable Height Secondary Clarifier Inlet At Hrsd Nansemond Treatment Plant, Matthew Poe

Civil & Environmental Engineering Theses & Dissertations

The Hampton Roads Sanitation District (HRSD) recently completed the first North American and center driven installation of the Hydrograv® Adapt Variable Height Secondary Clarifier Inlet (Adapt) at HRSD’s Nansemond Treatment Plant. This is a variable height inlet structure designed to decrease clarifier effluent turbidity and maintain low turbidity during high flow events. Low turbidity is achieved by feeding the secondary clarifier influent within the solids blanket during dry weather conditions and lifting the inlet structure during wet weather conditions to avoid disrupting the blanket. The Adapt clarifier was monitored alongside an identical fixed inlet clarifier to assess performance. Both clarifiers …


The Maritime Domain Awareness Center– A Human-Centered Design Approach, Gary Gomez Nov 2021

The Maritime Domain Awareness Center– A Human-Centered Design Approach, Gary Gomez

Political Science & Geography Faculty Publications

This paper contends that Maritime Domain Awareness Center (MDAC) design should be a holistic approach integrating established knowledge about human factors, decision making, cognitive tasks, complexity science, and human information interaction. The design effort should not be primarily a technology effort that focuses on computer screens, information feeds, display technologies, or user interfaces. The existence of a room with access to vast amounts of information and wall-to-wall video screens of ships, aircraft, weather data, and other regional information does not necessarily correlate to possessing situation awareness. Fundamental principles of human-centered information design should guide MDAC design and technology selection, and …


Illuminator, Volume 4, Issue 1, Batten College Of Engineering & Technology, Old Dominion University Nov 2021

Illuminator, Volume 4, Issue 1, Batten College Of Engineering & Technology, Old Dominion University

College of Engineering & Technology Newsletter

Fall 2021 issue of Illuminator, a monthly publication of ODU's Batten College of Engineering and Technology.


Risk Management And Biases In How Drivers Respond To Nuisance Flooding, Saige Hill, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Pragati Rawat, Carol Considine Nov 2021

Risk Management And Biases In How Drivers Respond To Nuisance Flooding, Saige Hill, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Pragati Rawat, Carol Considine

School of Public Service Faculty Publications

Nuisance flooding, or recurrent flooding, occurs during high tide and may be exacerbated when combined with other events such as heavy precipitation, strong winds, or storm surge. Sea level rise has contributed to increased frequency and duration of nuisance flooding in low-lying coastal areas and is causing community-specific impacts such as transportation disruption, road closures, compromises to life and property, overwhelmed storm water systems, and infrastructure damage. This chapter focuses on how drivers respond during nuisance flooding events. Specifically, we discuss how drivers in the Hampton Roads region of southeastern coastal Virginia obtain information about road flooding, how they respond, …


Protection Of Patient Privacy On Mobile Device Machine Learning, Matthew Nguyen Nov 2021

Protection Of Patient Privacy On Mobile Device Machine Learning, Matthew Nguyen

Cybersecurity Undergraduate Research Showcase

An existing StudentLife Study mobile dataset was evaluated and organized to be applied to different machine learning methods. Different variables like user activity, exercise, sleep, study space, social, and stress levels are optimized to train a model that could predict user stress level. The different machine learning methods would test if both patient data privacy and training efficiency can be ensured.


Cybersecurity Maturity Model Certification (Cmmc) Compliance For Dod Contractors, Sierra Burnett Nov 2021

Cybersecurity Maturity Model Certification (Cmmc) Compliance For Dod Contractors, Sierra Burnett

Cybersecurity Undergraduate Research Showcase

The DoD is currently taking a supply-chain risk management strategy to foster cybersecurity. This unique strategy is often referred to as CMMC which stands for “Cybersecurity Maturity Model Certification”. The approach requires that all the 300,000 DoD contractors acquire third-party authentication that may attain the requirements for the CMMC maturity level suitable to the work they desire to do for the DoD. CMMC typically examines the organization's capability to safeguard Federal Contract Information as well as CUI. It integrates various cybersecurity standards already in place and plots the best practices alongside processes to five maturity levels that range from the …


Systems Statistical Engineering – Hierarchical Fuzzy Constraint Propagation, Hengameh Fakhravar, Hesamoddin Tahami Oct 2021

Systems Statistical Engineering – Hierarchical Fuzzy Constraint Propagation, Hengameh Fakhravar, Hesamoddin Tahami

Engineering Management & Systems Engineering Faculty Publications

Driven by a growing requirement during the 21st century for the integration of rigorous statistical analyses in engineering research, there has been a movement within the statistics and quality communities to evolve a unified statistical engineering body of knowledge (Hoerl & Snee, 2010). Systems Statistical Engineering research seeks to integrate causal Bayesian hierarchical modeling (Pearl, 2009) and cybernetic control theory within Beer's Viable System Model (S Beer, 1972; Stafford Beer, 1979, 1985) and the Complex Systems Governance framework (Keating, 2014; Keating & Katina, 2015, 2016) to produce multivariate systemic models for robust dynamic systems mission performance. (Cotter & Quigley, 2018) …


Effects Of Cloud Computing In The Workforce, Kevin Rossi Acosta Oct 2021

Effects Of Cloud Computing In The Workforce, Kevin Rossi Acosta

Cybersecurity Undergraduate Research Showcase

In recent years, the incorporation of cloud computing and cloud services has increased in many different types of organizations and companies. This paper will focus on the philosophical, economical, and political factors that cloud computing and cloud services have in the workforce and different organizations. Based on various scholarly articles and resources it was observed that organizations used cloud computing and cloud services to increase their overall productivity as well as decrease the overall cost of their operations, as well as the different policies that were created by lawmakers to control the realm of cloud computing. The results of this …


Empirical Modeling Of Tilt-Rotor Aerodynamic Performance, Michael C. Stratton Oct 2021

Empirical Modeling Of Tilt-Rotor Aerodynamic Performance, Michael C. Stratton

Mechanical & Aerospace Engineering Theses & Dissertations

There has been increasing interest into the performance of electric vertical takeoff and landing (eVTOL) aircraft. The propellers used for the eVTOL propulsion systems experience a broad range of aerodynamic conditions, not typically experienced by propellers in forward flight, that includes large incidence angles relative to the oncoming airflow. Formal experiment design and analysis techniques featuring response surface methods were applied to a subscale, tilt-rotor wind tunnel test for three, four, five, and six blade, 16-inch diameter, propeller configurations in support of development of the NASA LA-8 aircraft. Investigation of low-speed performance included a maximum speed of 12 m/s and …


Network Modeling Of Hurricane Evacuation Using Data-Driven Demand And Incident-Induced Capacity Loss Models, Yuan Zhu, Kaan Ozbay, Kun Xie, Hong Yang, Ender Foruk Morgul Sep 2021

Network Modeling Of Hurricane Evacuation Using Data-Driven Demand And Incident-Induced Capacity Loss Models, Yuan Zhu, Kaan Ozbay, Kun Xie, Hong Yang, Ender Foruk Morgul

Civil & Environmental Engineering Faculty Publications

The development of a hurricane evacuation simulation model is a crucial task in emergency management and planning. Two major issues affect the reliability of an evacuation model: one is estimations of evacuation traffic based on socioeconomic characteristics, and the other is capacity change and its influence on evacuation outcome due to traffic incidents in the context of hurricanes. Both issues can impact the effectiveness of emergency planning in terms of evacuation order issuance, and evacuation route planning. The proposed research aims to investigate the demand and supply modeling in the context of hurricane evacuations. This methodology created three scenarios for …


Incorporating The 10th Edition Institute Of Traffic Engineers (Ite) Trip Generation Rates Into Virginia Department Of Transportation Guidelines, Kun Xie, Mecit Cetin, Hong Yang, Xiaomeng Dong Aug 2021

Incorporating The 10th Edition Institute Of Traffic Engineers (Ite) Trip Generation Rates Into Virginia Department Of Transportation Guidelines, Kun Xie, Mecit Cetin, Hong Yang, Xiaomeng Dong

Civil & Environmental Engineering Faculty Publications

The Institute of Transportation Engineers (ITE) released the Trip Generation (TG) 10th edition in 2017, which significantly updated its database, and some of its trip generation rates were substantially lower than those of earlier editions. This study aims to investigate the applicability of the TG 10th edition in various Virginia contexts and to recommend how to incorporate the TG 10th edition into state guidelines. The research team surveyed 31 state transportation agencies to obtain a clear understanding of current practices in the adoption of trip rates and trip estimation approaches. We systematically compared trip rates of TG 9th and 10th …


Exploration Of Corridor-Based Tolling Strategies For Virginia’S Express Toll Lanes, Shanjiang Zhu, Mecit Cetin, Hong Yang, Olcay Sahin, Atabak Mardan Aug 2021

Exploration Of Corridor-Based Tolling Strategies For Virginia’S Express Toll Lanes, Shanjiang Zhu, Mecit Cetin, Hong Yang, Olcay Sahin, Atabak Mardan

Civil & Environmental Engineering Faculty Publications

Virginia has invested significant resources in the development of express toll lanes (ETLs), which adjust toll rates dynamically based on the level of toll lane usage. A tool is needed to investigate the potential impact of the I-66 Outside-the-Beltway (OTB) ETLs on regional traffic patterns. This study developed a microscopic traffic simulation model in TransModeler to evaluate a set of corridor-based tolling strategies for the I-66 ETLs in NOVA. This model also considered the changes in vehicle occupancy, mode split, and departure time among travelers because of tolls based on locally collected data. An interactive map-based analyzer based on the …


Senior Elective Communications Systems Courses As Pathways To Capstone Projects In Electrical Engineering Technology Program, Otilia Popescu, Murat Kuzlu Jul 2021

Senior Elective Communications Systems Courses As Pathways To Capstone Projects In Electrical Engineering Technology Program, Otilia Popescu, Murat Kuzlu

Engineering Technology Faculty Publications

In any engineering program the capstone project is the most comprehensive work completed by the students, and is regarded as the pinnacle of their engineering studies, with all their course work culminating with this major design, implementation and reporting product. Coming up with the actual topic of the project is sometimes the most difficult part of the project, especially in programs where the project topics are not solely proposed by the faculty, and they are for the student and advisor to develop together. This is especially the case of engineering technology programs, where a large percentage of students have work …