Digital Commons Network^™

Particle Swarm Optimization For Critical Experiment Design, Cole Michael Kostelac

Masters Theses

“Critical experiments are used by nuclear data evaluators and criticality safety engineers to validate nuclear data and computational methods. Many of these experiments are designed to maximize the sensitivity to a certain nuclide-reaction pair in an energy range of interest. Traditionally, a parameter sweep is conducted over a set of experimental variables to find a configuration that is critical and maximally sensitive. As additional variables are added, the total number of configurations increases exponentially and quickly becomes prohibitively computationally expensive to calculate, especially using Monte Carlo methods.

This work presents the development of a particle swarm optimization algorithm to design …

Measurement Effects In Decision-Making, Devin Michael Burns, Charlotte Hohnemann

Psychological Science Faculty Research & Creative Works

When participants are shown a series of stimuli, their responses differ depending on whether they respond after each stimulus or only at the end of the series, in what we call a measurement effect. These effects have received paltry attention compared with more well-known order effects and pose a unique challenge to theories of decision-making. In a series of two preregistered experiments, we consistently find measurement effects such that responding to a stimulus reduces its impact on later stimuli. While previous research has found such effects in noncumulative tasks, where participants are instructed only to respond to the most recent …

Guiding A Human Follower With Interaction Forces: Implications On Physical Human-Robot Interaction, George L. Holmes, Keyri Moreno Bonnett, Amy Costa, Devin Michael Burns, Yun Seong Song

Psychological Science Faculty Research & Creative Works

This work challenges the common assumption in physical human-robot interaction (pHRI) that the movement intention of a human user can be simply modeled with dynamic equations relating forces to movements, regardless of the user. Studies in physical human-human interaction (pHHI) suggest that interaction forces carry sophisticated information that reveals motor skills and roles in the partnership and even promotes adaptation and motor learning. In this view, simple force-displacement equations often used in pHRI studies may not be sufficient. To test this, this work measured and analyzed the interaction forces (F) between two humans as the leader guided the blindfolded follower …

Incorporating Complex Sampling Weights In Multilevel Analyses Of Education Data, Ting Shen, Spyros Konstantopoulos

Psychological Science Faculty Research & Creative Works

Large-scale assessment survey (LSAS) data are collected via complex sampling designs with special features (e.g., clustering and unequal probability of selection). Multilevel models have been utilized to account for clustering effects whereas the probability weighting approach (PWA) has been used to deal with design informativeness derived from the unequal probability selection. However, the difficulty of applying PWA in multilevel models (MLM) has been generally underestimated and practical guidance is scarce. This study utilizes an empirical as well as a Monte Carlo simulation investigation to examine the performance of the multilevel pseudo maximum likelihood (MPML) estimation based on information derived from …

Pulsed-Active Microwave Thermography, Logan M. Wilcox, Mathias Bonmarin, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a thermographic nondestructive testing and evaluation technique that utilizes an electromagnetic-based excitation with a subsequent infrared measurement of the surface thermal profile of the material or structure of interest. AMT has been successfully applied to several aerospace and civil infrastructure applications. This work seeks to expand the performance of AMT by incorporating a signal processing technique common to traditional (flash-lamp) thermography, referred to as pulsed thermography (PT). PT operates on the premise of a pulsed excitation, as opposed to a constant or step excitation (ST) over a given time-period that is typical to traditional active …

Rejecting And Restricting Smart Home Technology, David Wright, Daniel Burton Shank

English and Technical Communication Faculty Research & Creative Works

Interest in and ownership of smart home voice assistants like Amazon Alexa and Google Home devices have exponentially increased in recent years. Many people may purchase or be gifted such devices without knowing their potential for connecting with other home technology, listening to private conversations, sharing information with companies, and creating problems due to misunderstanding vocal commands or technological capabilities. Concerns and worries about these devices may be exacerbated over time or by a specific incident. To understand reactions to such situations, we conducted semi-structured in-depth interviews with ten people who reported different types of worrying incidents with a range …

Self-Vernier Effect-Assisted Optical Fiber Sensor Based On Microwave Photonics And Its Machine Learning Analysis, Chen Zhu, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Optical Vernier Effect Has Been Recently Demonstrated as a Tool to Enhance the Sensitivity of Optical Fiber Interferometric Sensors and Has Become a Hot Topic in the Last Few Years. the Generation of the Vernier Effect Relies on the Superposition of Interferograms of Two Interferometers (A Sensing One and a Reference One) with Marginally Different Optical Path Differences (OPDs), Where an Amplitude Modulation-Like Signal is Sustained in the Output Spectrum. the Vernier Modulation Envelope Exhibits Significantly Magnified Sensitivity in Response to External Perturbations, compared to the Individual Sensing Interferometer, Providing a New Route to New Generations of Ultra-Sensitive Optical Fiber …

Neural Network Attitude Control System Design For The Wallops Arc-Second Pointer, Pavel Galchenko, Henry J. Pernicka

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Bulk Nanostructured Steels For Nuclear Reactor And Extreme Environment Applications, Maalavan Arivu

Doctoral Dissertations

"Candidate accident tolerant FeCrAl fuel (ATF) claddings for light water reactors (LWRs) need to be thinner than current Zircaloys owing to higher neutronic penalty, demanding an improvement in strength. Therefore, equal channel angular pressing (ECAP), and high-pressure torsion (HPT) were used to produce bulk ultra-fine grained and nanocrystalline Kanthal-D [KD; Fe-21Cr-5Al-0.026C (wt.%) alloy] which resulted in an improvement in strength of up to 3 times their nominal strength from grain boundary strengthening, and dislocation strengthening. Dynamic recovery was promoted due to ECAP at 520 oC rendering it with a large area fraction of less mobile low angle grain boundaries (LAGBs) …

Corrosion Resistance Performance Investigation Of Mild Steel Bar Coated With Magnesium Phosphate Cement Paste, Fan Zhang

Doctoral Dissertations

"In this research study, the anti-corrosion mechanism of reinforcement embedded in magnesium potassium phosphate cement (MKPC) is explored. In addition, one type of additives, metakaolin, and one type of retarder, boric acid, are employed in MKPC to modify its properties in order to further investigate corrosion resistance and to achieve mass-production coating reinforcement at the work site. This coating method may be practical for some underwater construction and some traditional reinforcement concrete structures to reduce the reinforcement corrosion rate and to eventually extend service life in both repair and new construction applications.

By comparing the electrochemical properties of bare ribbed …

Signal Integrity Analysis And Electromagnetic Inteference Modeling For Autonomous Vehicles, Yuandong Guo

Doctoral Dissertations

"An autonomous vehicle (AV) may employ various sensors to detect the environment, and the hardware for self-driving should be able to process large volume of sensor data and make real-time decisions. For signal integrity (SI), both the bandwidths and data rates of the high-speed channels should meet the requirements. The electromagnetic interference (EMI) noise may become a major concern with the ever-increasing number of electric modules. This research focuses on both SI analysis and EMI modeling for AVs. The first topic is accurate and broadband three-phase motor modeling. The novel modeling methodology for a typical three-phase motor is presented, using …

Computational Fluid Dynamics Techniques For Multiphase Flow Systems, Jose Sebastian Uribe Lopez

Doctoral Dissertations

"Mathematical modelling of multiphase flow systems has been a major and persistent challenge over the last decades. Vast attempts to obtain predictive models can be found reported in literature, where major advances can be recognized in recent years, paired to enhancements in computer science and engineering. Notwithstanding, universally valid models with a mechanistic development are far from being achieved. The current status of modelling any multiphase flow system relies on the model order reduction of purely theoretical models. Such reductions and simplifications become the source of deviations in the predictions of the experimentally measured parameters and will constrain the applicability …

Application Of Machine Learning In Geophysics: Ranking Teleseismic Shear Wave Splitting Measurements And Classifying Different Types Of Earthquakes, Yanwei Zhang

Doctoral Dissertations

"During the past decades, applications of Machine Learning have been explosively developed to solve various academic and industrial problems, and over-human performance has been shown in diverse areas. In geophysical research, Machine Learning, especially Convolutional Neural Network (CNN), has been applied in numerous studies and demonstrated considerable potential. In this study, we applied CNN to solve two geophysical problems, ranking teleseismic shear splitting (SWS) measurements and classifying different types of earthquakes.

For ranking teleseismic SWS measurements, we utilized a CNN-based method to automatically select reliable SWS measurements. The CNN was trained by human-verified teleseismic SWS measurements and tested using synthetic …

Novel Ferromagnetic Materials With Improved Mechanical Performance, Wesley Alexander Everhart

Doctoral Dissertations

"The ductility of intermetallics has long been a hindrance to their broad adaptation despite a significant range of properties such as magnetic, half-metallic, and shape memory behavior. The lack of a general theory for the ductility of intermetallics along with the lack of prior art that experimentally measured mechanical properties drives the need for significant investment in many of these novel magnetic materials in order to even understand, let alone correct, poor ductility.

This dissertation includes work that explored the effect of vanadium content and quenching rate on the microstructure and ductility of Fe-Co alloys. Results indicated that a martensitic …

Multifunctional Behaviors Of Two-Dimensional Materials And Their Composites, Yanxiao Li

Doctoral Dissertations

"Two-dimensional (2D) materials, including graphene, transition metal carbides or nitrides (TMC/Ns), have rich surface chemistry, superb electrical and mechanical properties. These unique properties make them ideal for multifunctional devices. Among them, we focused on graphene and TMC/Ns (i.e., MXenes), as well as their composites. Unlike the well-known graphene, MXenes, are relatively new and typically synthesized by the selective etching of the “A” layers from the layered carbides and /or nitrides known as MAX phases, which introduce MXenes with rich terminal groups (e.g. -O-, -OH, -F).

During my Ph.D. study, firstly, the adhesive and frictional behaviors, which are related to successful …

Influences Of The Internal Residual On Combustion Instabilities In The Misfire And Partial Burn Regimes Of A Dilute Spark-Ignition Engine, Rachel Inez Stiffler

Doctoral Dissertations

"Dilution in spark-ignition (SI) engines can improve fuel consumption and reduce emissions; however, increased levels of dilution either from excess oxidizer or exhaust gas recirculation (EGR) causes combustion to become more strained and cycle-to-cycle variations increase. At high levels of dilution incomplete combustion events (i.e. misfires and partial burns) start to occur, which cause combustion instabilities and eventually a dilute limit is reached. It is known the combustion instabilities seen are primarily due to the feed-forward mechanism present in the residual gases, but it is still unknown what about the residual is influencing the dynamics under high levels of dilution …

A Variable Node Optimization Model For Byzantine Fault Tolerant Systems, Ian Robert Fulton

Masters Theses

“Byzantine Fault Tolerance (BFT) has been a major subject of study over the last two decades with increasing societal dependance on secure, correct, and reliable computer systems and online services. This research presents a model for high-level optimization of emerging systems that rely on these BFT algorithms and use a variable numbers of decision nodes. The model highlights the relationship between the security of a system and its efficiency. Two experiments were performed to determine system performance by varying the number of compromised nodes, decision nodes, and total nodes. They examine the probability that a transaction will be compromised based …

State Level Trends In Renewable Energy Procurement Via Solar Installation Versus Green Electricity, Eric Michael Hanson

Masters Theses

“In the past 5 years, consumer options for procuring renewable energy have increased, ranging from rooftop solar installation to utility green pricing to Community Choice Aggregation. These options vary in terms of costs and benefits to the consumer as well as grid integration implications. However, little is known regarding how the presence of a wide range of options for utility-scale renewable procurement affects demand for distributed residential solar installations. In theory, there are three possible relationships, (1) positive correlation, where utility-scale and distributed resources complement each other to increase overall production, (2) negative correlation, where utility-scale and distributed resources are …

Characterization Of Cermet Fuel For Nuclear Thermal Propulsion (Ntp), James Floyd Mudd

Masters Theses

“A manned flight to Mars is met with many technical challenges, not the least of which is the development of propulsion technology capable of moving a transit vehicle from Earth orbit to Mars orbit. NASA is investigating Nuclear Thermal Propulsion (NTP) as a way of reducing flight time and providing the option for a mid-mission abort. NTP, which uses a high temperature nuclear reactor to heat a propellant, requires advanced fuel materials capable of withstanding temperatures well in excess of 2000 K. Among the fuel options are ceramic metal (cermet) composites composed of refractory metals and Ultra-High Temperature Ceramics (UHTCs). …

Experimental Optimization Of Simulated Ring Rolling Operation For Heavy Rail Industry, Jacob M. Summers

Masters Theses

“Industrially cast AISI 1070 steel wheel pre-forms from Amsted Rail Co. were experimentally hot rolled to simulate the conditions for industrial wheel rolling. Ring rolling of near net shape castings can improve location specific properties by decreasing segregation, closing porosity, and reducing grain size without the use of multiple forging operations in a traditional forging line. As-cast wheel sections were subjected to thermomechanical processing routes using a 2-high rolling mill in a temperature range of 830°C to 1200°C. The goal being to simulate the ring rolling process and optimize benefits of mechanical properties of the as-rolled steel. Charpy V- and …

Validation Of Athlet-Cd With Cora-28 Test, Murat Tuter

Masters Theses

“Following the incidents at Chernobyl and Fukushima, severe accidents at nuclear power plants (NPP) have become a global concern. These accidents generally occur because of a failure in the reactor cooling system (RCS) and result in the melting of the reactor core and fission product release. This event is mostly caused by a LOCA, loss of flow accident, station blackout or loss of heat sink. During a severe accident, generation of hydrogen as a result of steam-zircaloy fuel cladding is a significant safety concern. To better understand and prevent the hydrogen generation issue, safety related experiments and safety related codes …

Several Problems In Nonlinear Schrödinger Equations, Tim Van Hoose

Masters Theses

“We study several different problems related to nonlinear Schrödinger equations….

We prove several new results for the first equation: a modified scattering result for both an averaged version of the equation and the full equation, as well as a set of Strichartz estimates and a blowup result for the 3d cubic problem.

We also present an exposition of the classical work of Bourgain on invariant measures for the second equation in the mass-subcritical regime”--Abstract, page iv.

Array Signal Processing For Source Localization And Enhancement, Sohel J. Patel

Doctoral Dissertations

“A common approach to the wide-band microphone array problem is to assume a certain array geometry and then design optimal weights (often in subbands) to meet a set of desired criteria. In addition to weights, we consider the geometry of the microphone arrangement to be part of the optimization problem. Our approach is to use particle swarm optimization (PSO) to search for the optimal geometry while using an optimal weight design to design the weights for each particle’s geometry. The resulting directivity indices (DI’s) and white noise SNR gains (WNG’s) form the basis of the PSO’s fitness function. Another important …

Are Socially Responsible Exchange-Traded Funds Paying Off In Performance?, Ya Dai, Liang Guo, Steve Liu, Hongxian Zhang

Business and Information Technology Faculty Research & Creative Works

This study examines the Socially Responsible (SR) exchange-traded funds (ETFs) by comparing their risk-adjusted performance with a matched group of conventional ETFs in the U.S. equity market. In contrast to prior studies that focus on actively managed mutual funds, we find that the risk-adjusted returns of SR ETFs are significantly lower than those of conventional ETFs during the 2005–2020 period. Such underperformance is only observed in non-crisis periods but not in economic crisis periods (i.e., the 2020 pandemic recession and 2008 financial turmoil). We attribute the observed underperformance of SR ETFs during the non-crisis periods to their limited diversification of …

The Impact Of Perceived Manipulation, Motives, And Ethicality In Cause-Related Marketing: A Crm+ Model, Nathan W. Twyman, Sarah M. Stanley, Cassandra C. Elrod, Tamara M. Masters

Business and Information Technology Faculty Research & Creative Works

We Developed a CRM+ Model using Experimentation and Structural Equation Modeling Analysis. CRM+ Demonstrates Previously Unexplored Interrelationships among Consumer-Perceived Manipulation, Brand Motives, Perceived Ethicality of the Cause-Related Marketing, and Brand Attitude. CRM+ Reveals that Perceived Ethicality of the CRM Has a Significant Positive Effect on Brand Attitude, Though It is Not as Pronounced as the Effect of Perceived Altruistic Motives. Egoistic Motives Decrease Ethicality Perceptions But Has No Direct Effect on Brand Attitude. Altruistic Motive Perceptions Diminish Egoistic Motive Perceptions. CRM+ Suggests Marketing Managers Should Prioritize Emphasizing Altruistic Motives and Ethicality of the Partnership over Downplaying Egoistic Motives.

Tension-Stiffening Effect Consideration For Modeling Deflection Of Cracked Reinforced Uhpc Beams, Le Teng, Rongling Zhang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tension-stiffening effects can significantly influence the flexural performance of cracked reinforced concrete specimens. Such effect is amplified for fiber-reinforced concrete, given the fact that fibers can bridge the cracks. The objective of this study was to develop a model to predict the deflection of cracked reinforced ultra-high performance concrete (R-UHPC) beam elements. The modeling approach characterized the average bending moment of inertia by combining the existing model used for conventional reinforced concrete and the analytical model of stress distribution of UHPC along the cross-section. The finite element analysis (FEA) was employed to evaluate the flexural deflection based on the average …

Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the recent widespread adoption of LED lighting in outdoor areas, numerous concerns have been raised about the potential for harmful effects on humans, animals, plants, and the night sky. These stem from the high blue light content of some LED bulbs and an incentive to increase lighting levels caused by higher efficiency and lower costs. While new lighting installations are often described as environmentally friendly due to their energy efficiency, factors such as light pollution are often neglected or not given enough weight. This research focuses on optimizing the design of exterior lighting for human, environmental, and economic factors …

Development Of Terminology Of Word-Formation Synthesis. Features Of The Terminological System (Based On The Verbs Of The Sound Of The Russian Language), Irina V. Ivliyeva

Arts, Languages and Philosophy Faculty Research & Creative Works

English Abstract:

The purpose of the research is to present the terminology of word-formation synthesis as an organized system, to identify the stages of development of relevant terms. The scientific novelty of the research lies in the fact that a structured corpus of terms of word-formation synthesis with elements of definitional analysis is introduced into scientific circulation. different stages of research. The system of terms of modification synthesis is applied and studied in practice – in the author's search program for web extraction of verbs of sound from the databases of modern dictionaries and the Russian National Corpus.

Russian Abstract: …

Polybenzodiazine Aerogels: All-Nitrogen Analogues Of Polybenzoxazines Synthesis, Characterization, And High-Yield Conversion To Nanoporous Carbons, Vaibhav A. Edlabadkar, Saidulu Gorla, Rushi U. Soni, A. B.M.Shaheen Ud Doulah, Joseph Gloriod, Samuel Hackett, Nicholas Leventis, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

Tetrahydroquinazoline (THQ) was designed as an all-nitrogen analogue of main-stream benzoxazine monomers. THQ solutions in DMF gelled at 100 °C via HCl-catalyzed ring-opening polymerization to polybenzodiazine (PBDAZ) wet gels, which were dried in an autoclave with supercritical fluid CO₂ to aerogels. These as-prepared PBDAZ-100 aerogels undergo ring-fusion aromatization at 240 °C under O₂. This oxidized form is referred to as PBDAZ-240. Chemical identification of PBDAZ-100 and PBDAZ-240 relied on consideration of all nine possible polymerization pathways, in combination with elemental analysis, infrared and solid-state 13C NMR spectroscopy, and 15N NMR spectroscopy of aerogels from the selectively 15N-enriched …

Anomaly Based Incident Detection In Large Scale Smart Transportation Systems, Jaminur Islam, Jose Paolo Talusan, Shameek Bhattacharjee, Francis Tiausas, Sayyed Mohsen Vazirizade, Abhishek Dubey, Keiichi Yasumoto, Sajal K. Das

Computer Science Faculty Research & Creative Works

Modern smart cities are focusing on smart transportation solutions to detect and mitigate the effects of various traffic incidents in the city. To materialize this, roadside units and ambient trans-portation sensors are being deployed to collect vehicular data that provides real-time traffic monitoring. In this paper, we first propose a real-time data-driven anomaly-based traffic incident detection framework for a city-scale smart transportation system. Specifically, we propose an incremental region growing approximation algorithm for optimal Spatio-temporal clustering of road segments and their data; such that road segments are strategically divided into highly correlated clusters. The highly correlated clusters enable identifying a …