Engineering Commons^™

Business Continuity Planning For A Medium-Sized Hotel Under Covid-19 Outbreak, Arunlak Tangtanapaiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Business Continuity Planning is a subjective conceptual framework prominently used in operations related to supply chain, information technology, or governmental organizations. In this research, we have applied the concept of business continuity planning to a service business during the COVID–19 outbreaks, whose aim is to determine the business continuity objective with the maximum operational tolerable period. The proposed framework has been evaluated based on the ANOVA Test of a guest's service questionnaire of a hotel in Rayong, Thailand. We find that, by reducing business operating cost via staff working hours reduction and limiting service functions of the hotel to the …

Spatial Indexing For System-Level Evaluation Of 5g Heterogeneous Cellular Networks, Roohollah Amiri, Eren Balevi, Jeffrey G. Andrews, Hani Mehrpouyan

Electrical and Computer Engineering Faculty Publications and Presentations

System level simulations of large 5G networks are essential to evaluate and design algorithms related to network issues such as scheduling, mobility management, interference management, and cell planning. In this paper, we look back to the idea of spatial indexing and its advantages, applications, and future potentials in accelerating large 5G network simulations. We introduce a multi-level inheritance based architecture which is used to index all elements of a heterogeneous network (HetNet) on a single geometry tree. Then, we define spatial queries to accelerate searches in distance, azimuth, and elevation. We demonstrate that spatial indexing can accelerate location-based searches by …

Cyber-Informed: Bridging Cybersecurity And Other Disciplines, Char Sample, Sin Ming Loo, Connie Justice, Eleanor Taylor, Clay Hampton

Electrical and Computer Engineering Faculty Publications and Presentations

A recent study by Cybersecurity Ventures (Morgan 2018), predicts that 3.5 million cybersecurity jobs around the world will be unfilled by 2021. In the United States, the demand for professionals with cybersecurity expertise is outpacing all other occupations (NIST 2018). These reports, along with many others, underpin the need for increasing workforce development initiatives founded in cybersecurity principles. The workforce shortage is across all cybersecurity domains, yet problems continue to persist, as the lines between combatants and non-combatants are blurred. Combating this persistent threat, which is a 24/7 operation, requires a more aggressive and inclusive approach. Higher education institutions are …

Ultra-Low Power Circuits And Architectures For Neuromorphic Computing Accelerators With Emerging Tfets And Rerams, Jie Lin

Electronic Theses and Dissertations, 2020-2023

Neuromorphic computing using post-CMOS technologies is gaining increasing popularity due to its promising potential to resolve the power constraints in Von-Neumann machine and its similarity to the operation of the real human brain. To design the ultra-low voltage and ultra-low power analog-to-digital converters (ADCs) for the neuromorphic computing systems, we explore advantages of tunnel field effect transistor (TFET) analog-to-digital converters (ADCs) on energy efficiency and temperature stability. A fully-differential SAR ADC is designed using 20 nm TFET technology with doubled input swing and controlled comparator input common-mode voltage. To further increase the resolution of the ADC, we design an energy …

Classical Engineering Systems Provide Behavioral Analog For Ephemeral Insect And Plant Biomechanics, Nicholas Smith

Electronic Theses and Dissertations, 2020-2023

In this dissertation we consider ephemeral behaviors of two small-scale living systems, mosquitoes and citrus fruit reservoirs. While these two systems share few obvious commonalities, they both express life events that are complex and conclude within approximately 50 milliseconds. We utilize high-speed videography, between 1,000-16,000 fps, to detail how complex behavior can be modeled as classical engineering systems. Beginning with the larger organism we assessed the landing and takeoff behavior of Aedes aegypti mosquitoes to ascertain the secrets of their covert interaction with humans. At takeoff, mosquitoes decrease pushing contact time with substrates of low friction through a modified takeoff …

Inertial Orbit Estimation Using Multiple Space Based Observers: A New Measurement Model, James Hippelheuser

Electronic Theses and Dissertations, 2020-2023

Presented within this work is a new method for inertial orbit estimation of an object, either known or unknown, adaptable to a network of low-cost observation satellites. The observation satellites would only require a monocular camera for line of sight measurements. Using the line of sight measurements of each observer, a pair of orthogonal geometric planes that intersect both the observation satellite and the target are created. The intersection of the two planes in the inertial frame defines the new measurement model that is implemented with multiple observation nodes. Total system observability is analyzed and the instantaneous (per node) observability …

Evaluating The Performance And Impacts Of Seawater Regeneration In An Anion Exchange Process, Daniel Whalen

Electronic Theses and Dissertations, 2020-2023

This research investigated the use of seawater regeneration for anion exchange (AIX) processes. Seawater and salt-supplemented seawater regeneration of chloride-form anion resin were evaluated in regard to (1) operational performance efficiency of sulfate and natural organic matter removal, (2) competing exchange of bromide during regeneration, and (3) brominated disinfection by-product (DBP) formation due to bromide leakage. The first component involved bench-scale research that revealed that seawater-based regeneration led to bromide leakage that could be mitigated to an average of 1.82 mg/L using 1% salt-supplemented seawater, and 1.25 mg/L using 3% salt-supplemented seawater. Conceptual cost comparisons revealed that the use of …

Piezospectroscopic Sensing Systems - Multi-Scale And In-Situ Sensing Technology For Structural Integrity, Remelisa Esteves

Electronic Theses and Dissertations, 2020-2023

The aerospace industry relies on nondestructive evaluation (NDE) to ensure aircraft safety and will benefit from methods that allow for early damage detection. Photoluminescence piezospectroscopy (PS) has demonstrated stress and damage sensing of substrates when coupled with alpha-alumina nanoparticles in a polymer matrix applied as a sensor coating. Alpha phase alumina exhibits photoluminescent spectral emission lines (R-lines) that shift due to changes in the stress state of the alumina. The coatings' capability for sensing early subsurface damage suggests the potential for implementing stress sensing paint for integrity monitoring of aircraft structures. To achieve a viable stress sensing coating that can …

Application Of Reliability Centered Maintenance In Railway Tracks, Sarita Rattanakunuprakarn

Electronic Theses and Dissertations, 2020-2023

Rail transport has played a significant role for a long time in the U.S. history. As other alternative transport modes have been developed, rail transport has increasingly faced more challenges to stay competitive. While heavy use of the rail, shortened service life and the need to meet consumer expectations have placed challenges, maintenance has become an integral part of the railway industry to assure efficacy and reliability of rail transportation. For this reason, there is a constant need to improve maintenance for a number of purposes, such as safety, quality, capacity, reliability, availability, punctuality, etc. In addition, optimizing maintenance strategy …

Chemically Stabilized Oil-In-Water Emulsion Separation Using A Custom Aquaporin-Based Polyethersulfone (Pes) Forward Osmosis Membrane System, Annmarie Ricchino

Electronic Theses and Dissertations, 2020-2023

The stability of oil-in-water emulsions is enhanced by the presence of surfactants in the water, thereby increasing difficulty of remediation. In this study, mineral oil and a standard bilge mix (SBM) were used as model oils for forward osmosis (FO) performance evaluation and two different high-concentration feed solutions (FS) were tested: 10,000 and 100,000 ppm oil/surfactant (9:1 Oil/Surfactant, wt %). It was hypothesized that the charge-charge interactions between the surfactant portion of the micelles and the membrane would play an important role in membrane fouling. Therefore, the effects of both an anionic surfactant (sodium dodecyl sulfate [SDS]) and a nonionic …

Mobile Health Technology To Enhance Healthcare Service Delivery In Developing Nations (Saudi Arabia), Nawaf Khan

Electronic Theses and Dissertations, 2020-2023

Saudi Arabia is among the countries that have very high prevalence rates of diabetes and hypertension, with prevalence rates of almost 18% and 25%, respectively. The majority of patients with diabetes and hypertension fail to manage their diseases and to show up for their follow up appointments. Mhealth technology is among the interventions that have been recently adopted to overcome these issues and improve the quality of healthcare services. This study aims to evaluate the effectiveness of a mobile phone application named diabetes and hypertension application (DHA Tracking) to promote adherence for patients with diabetes and hypertension in Mecca, Saudi …

Thermodynamic Theory Of Heavily Multimoded Nonlinear Optical Systems, Fan Wu

Electronic Theses and Dissertations, 2020-2023

The quest for ever higher information capacities has brought about a renaissance in multimode optical waveguide systems. This resurgence of interest has recently initiated a flurry of activities in nonlinear multimode fiber optics. The sheer complexity emerging from the presence of a multitude of nonlinearly interacting modes has led not only to new opportunities in observing a host of novel optical effects that are otherwise impossible in single-mode settings, but also to new theoretical challenges in understanding their collective dynamics. In this dissertation, we present a consistent thermodynamical framework capable of describing in a universal fashion the exceedingly intricate behavior …

Climatic And Topologic Controls On The Complexity Of River Networks, Sevil Ranjbar Moshfeghi

Electronic Theses and Dissertations, 2020-2023

The emergence and evolution of channel networks are controlled by the competition between the hillslopes and fluvial processes on the landscape. Investigating the geomorphic and topologic properties of these networks is important for developing predictive models describing the network dynamics under changing environment as well as for quantifying the roles of processes in creating distinct patterns of channel networks. In this dissertation, the response of landscapes to changing climatic forcing via numerical-modeling and field observations was investigated. A new framework was proposed to evaluate the complexity of catchments using two different representations of channel networks. The structural complexity was studied …

Leveraging Augmented Reality For Real-Time Operational Performance Management, Joshua Nelson

Electronic Theses and Dissertations, 2020-2023

Augmented Reality (AR) projects a virtual overlay onto real space so that the user can see a superimposed image over the real-world background. Although AR has advanced recently and a breadth of applications can be found in practice, they are focused on simple tasks with few examples of more complex work tasks. One area that could benefit from advancing AR technology is operations management, specifically operational performance measurement (OPM); however, a brief review of the literature reveals that this potential application area has not yet been explored. Therefore, the purpose of this work is to investigate the application of AR …

A Computational Biomechanical Model-Based Optimization Of Fulcrum Support In Orthosis Enabled Closed Reduction Of Developmental Dysplasia Of The Hip, Christopher Rose

Electronic Theses and Dissertations, 2020-2023

Hip abduction orthosis devices (HAOD) are used to reduce the hip joint of infants affected by developmental dysplasia of the hip (DDH). HAOD have been successful for mild cases of DDH and ineffective for severe cases. Efforts in understanding the biomechanics of lower limbs have been made to improve the success rate of current treatment methods, especially for Grade IV dislocations (G4). The aim of this dissertation is twofold: first, it proposes the use of a varying fulcrum point (FP) located below the leg to improve DDH treatment; and secondly, it defines the optimal FP (OP) location for a broad …

Novel Fibers And Components For Space Division Multiplexing Technologies, Juan Carlos Alvarado Zacarias

Electronic Theses and Dissertations, 2020-2023

Passive devices and amplifiers for space division multiplexing are key components for future deployment of this technology and for the development of new applications exploring the spatial diversity of light. Some important devices include photonic lantern (PL) mode multiplexers supporting several modes, fan-in/fan-out (FIFO) devices for multicore fibers (MCFs), and multimode amplifiers capable of amplifying several modes with low differential modal gain penalty. All these components are required to overcome the capacity limit of single mode fiber (SMF) communication systems, driven by the growing data capacity demand. In this dissertation I propose and develop different passive components and amplifiers for …

Safety Evaluation Of Innovative Intersection Designs: Diverging Diamond Interchanges And Displaced Left-Turn Intersections, Ahmed Abdelrahman

Electronic Theses and Dissertations, 2020-2023

Diverging diamond interchanges (DDIs) and Displaced left-turn intersections (DLTs) are designed to enhance the operational performance of conventional intersections that are congested due to heavy left-turn traffic volumes. Since drivers are not familiar with these types of intersections, there is a need to evaluate their safety performance to validate their effect, and to estimate reliable and representative Crash Modification Factors (CMFs). The safety evaluation was conducted based on three common safety assessment methods, which are before-and-after study with comparison group, Empirical Bayes before-and-after method, and cross-sectional analysis. Furthermore, since DLTs showed poor safety performance, the study also investigated the operational …

Dynamic Modeling And Simulation Of A Power Plant Steam Condenser On The Siemens Sppa-T3000 Platform, Mohammad Odeh

Electronic Theses and Dissertations, 2020-2023

With rapidly increasing computational power, modeling and simulation of complex systems is gradually becoming the norm for evaluating and predicting performance. This research focuses on modeling and simulating thermodynamic behavior of condensers within Combined Cycle Power Plants. This is particularly useful for power generation companies as this allows a wide range of operating conditions to be simulated and characterized without risking damage or the need to shut down the power plant, all of which results in losing revenue in the process. Moreover, being able to observe the thermodynamic evolution of the system provides useful insight into efficiency and response to …

Monolithic Thin-Film Lithium Niobate Scanning Micromirror: Design And Simulation, Abimanyu Veerappan

Electronic Theses and Dissertations, 2020-2023

In this thesis, a novel scanning micromirror is introduced in which a thin layer of lithium niobate (few micrometer thick) is utilized as both as the structural material and the actuating piezoelectric medium. In this novel monolithic design, the conventional composite torsional hinges are avoided. The finite element simulations performed and reported in here indicate that the proposed design offers a superior performance in terms of higher scan angle and linear angle control compared to the existing solutions for the same dimensions. The simulation results predict an optical scan angle of 125.6° at a resonant frequency of 550 Hz using …

Ac Conductivity Studies Of Polyethylene-Oxide-Garnet Type Li7la3zr2o12 Hybrid Composite Solid Polymer Electrolyte For Li-Ion Battery, Parisa Bashiri

Wayne State University Dissertations

Solid electrolytes including ceramics and polymers are considered to be the ultimate substitute for organic liquid electrolytes currently used in commercialized lithium ion batteries to address the safety concerns due to Li dendrite growth and internal short circuiting. However, low ionic conductivity due to high grain boundary resistance in ceramics and semi-crystalline nature of polymers has held back the solid electrolytes from being used in Li-ion batteries. Polyethylene oxide (PEO), complexed with a Li-salt, is a well-studied polymer electrolyte showing ionic conductivity properties at room temperature. However, the coexistence of amorphous and crystalline regions at room temperature (< Tm, the melting temperature) has

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Evaluation Of Far-Side Occupant Safety Based On Numerical Modeling, Syed Akhtar Imam

Wayne State University Dissertations

The objective of this study was to augment the knowledge of the far-side occupant injury biomechanics in side impact vehicle crashes. Most research studies conducted to investigate the far-side occupant injuries are through the field crash data for a better understanding of human impact responses, injury mechanisms, and injury tolerance levels. The data obtained from field data is also used in the development of injury mitigation technologies, such as safety belts, airbags, etc. A field data represents the injury outcome of an automotive crash, but it doesn’t leave behind enough information for in-depth knowledge. The use of cadaver is the …

Development Of Rat Head Finite Element Model And Tissue Level Biomechanical Threshold For Traumatic Axonal Injury, Runzhou Zhou

Wayne State University Dissertations

Traumatic brain injury (TBI) is caused by local tissue deformation at the time of trauma, leading to neurological dysfunction. In the United States alone, 2.87 million people sustain a TBI each year, of which one-fifth results in death. Traumatic axonal injury (TAI) is a well-recognized consequence of every fatal head injury and more than 85% of vehicular crash-related blunt head injuries. The most common and important pathologic feature of TBIs are multifocal changes to axons in the white matter produced by rapid head acceleration/deceleration during a traumatic event with consequent local shear/tension on neural tissue and axons contributing to secondary …

Low- And High-Drag Intermittencies In Turbulent Channel Flows, Rishav Agrawal, Henry C.-H. Ng, Ethan A. Davis, Jae Sung Park, Michael D. Graham, David J.C. Dennis, Robert J. Poole

Department of Mechanical and Materials Engineering: Faculty Publications

Recent direct numerical simulations (DNS) and experiments in turbulent channel flow have found intermittent low- and high-drag events in Newtonian fluid flows, at Reτ = uτh/ν between 70 and 100, where uτ, h and ν are the friction velocity, channel half-height and kinematic viscosity, respectively. These intervals of low-drag and high-drag have been termed “hibernating” and “hyperactive”, respectively, and in this paper, a further investigation of these intermittent events is conducted using experimental and numerical techniques. For experiments, simultaneous measurements of wall shear stress and velocity are carried out in a channel flow facility using hot-film anemometry (HFA) and laser …

Development Of An Ndt Tool For In-Situ Assessment Of Prestress Loss, Bibo Zhong, Jinying Zhu, George Morcous

Nebraska Department of Transportation: Research Reports

The research objective is to develop a non-destructive testing (NDT) method to evaluate the prestress loss in prestressed concrete bridge girders using ultrasonic waves. The work principle is based on acoustoelastic effect - ultrasonic wave velocity varies with stress level in prestressed concrete. A self-reference test setup was proposed to measure wave velocity in two orthogonal directions (prestress and unstressed directions) in the girder. This setup will be able to reduce effects of material variation and temperature change.

The concept was first validated on small concrete specimens (cylinders and beams) in laboratory. A signal analysis algorithm was developed to reliably …

Experimental Studies Of Interfacial Behavior Of Contact System During Liquid Mediated Rough Surfaces Separation, Nhat Le

All Graduate Theses, Dissertations, and Other Capstone Projects

In the applications related to liquid-solid interface, their operation could be affected by the properties of the interface especially the applications that have infinitesimal interaction force at the interface surface and high interaction velocity. This study provides real time dynamic force measurement in separation process along with the real time image acquisition to explain the deviation between theoretical and experimental methods. The experimental design, setup and initial conditions for experiment are described in detail for further study related to liquid separating force. The simulation model is created to apply the theoretical model in prediction of meniscus force for different initial …

Uncertainty-Aware Brain Lesion Visualization, Christina Gillmann, Dorothee Saur, Thomas Wischgoll, Karl T. Hoffman, Hans Hagen, Ross Maciejewski, Gerik Scheuermann

Computer Science and Engineering Faculty Publications

A brain lesion is an area of tissue that has been damaged through injury or disease. Its analysis is an essential task for medical researchers to understand diseases and find proper treatments. In this context, visualization approaches became an important tool to locate, quantify, and analyze brain lesions. Unfortunately, image uncertainty highly effects the accuracy of the visualization output. These effects are not covered well in existing approaches, leading to miss-interpretation or a lack of trust in the analysis result. In this work, we present an uncertainty-aware visualization pipeline especially designed forbrain lesions. Our method is based on an uncertainty …

Biom 4110/6110: The Science Of Medicine (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Integration of fundamental principles from physics, chemistry, biology and mathematics, and applications of these principles to solve problems in medicine.

Topical Review Of Vulnerability Management For Local Hampton Roads Industry, Gregory W. Hubbard Jr., Matthew Eunice

OUR Journal: ODU Undergraduate Research Journal

The progress towards an interconnected digital world offers an exciting level of advancement for humanity. Unfortunately, this “online” connection is not safe from the threats and dangers typically associated with physical operations. With the foundation of Cyber Command of DoD cyberspace, the United States Government is taking a prominent stance in cyberspace operations. Like the federal government, both industries and individuals are not immune and are oftentimes unknowingly at risk to cyberattack. This report hopes to bring awareness to common vulnerabilities in multi-user networks by describing a historical background on cyber security as well as outlining current methods of vulnerability …

Application Of Quantum Cryptography To Cybersecurity And Critical Infrastructures In Space Communications, Rita Meraz, Linda Vahala

OUR Journal: ODU Undergraduate Research Journal

As society becomes more dependent on technology and the internet, critical infrastructure, which provides the fundamental services that millions of people depend on, becomes more vulnerable to cyber threats. This paper presents the importance of cybersecurity in critical infrastructure addressing the communications sector which is prevailed by space systems. It gives an overview of laser communications via satellite, and it argues the utility that quantum cryptography can provide to secure the data transmitted between communication satellites and ground stations from cyber attacks. Common encryption algorithms are briefly introduced as well as a review on quantum computing. Quantum cryptography is still …

Systemic Analysis Of The Use Of Artificial Intelligence (Ai) In Regulating Terrorist Content On Social Media Ecosystem Using Functional Dependency Network Analysis (Fdna), Alaina Roman, C. Ariel Pinto

OUR Journal: ODU Undergraduate Research Journal

This research is a systemic analysis of emerging risks to the use Artificial Intelligence (AI) in regulating terrorist content on social media ecosystems using Functional Dependency Network Analysis (FDNA), a proven system-design-and-analysis tool). The research has three phases: 1) framing the problem by identifying and describing AI ecosystem elements as intended, implied and explicit objectives, discernible attributes, and performance indictors; 2) describing the idealized problem-solved scenario, which includes detailing ‘success’ states of the ecosystem; and 3) systemic risk analysis including identifying failure scenarios for each element and establishing causalities among elemental attributes leading to failure scenarios. This research contributes toward …