Engineering Commons^™

Effect Of Shock Tunnel Geometry On Shockwave And Vortex Ring Formation, Propagation, And Head On Collision, Rachel L. Bauer, Emily M. Johnson, Alexander D. Douglas, Catherine E. Johnson

Mining Engineering Faculty Research & Creative Works

Vortex ring research primarily focuses on the formation from circular openings. Consequently, the role of tunnel geometry is less understood, despite there being numerous research studies using noncircular shock tunnels. This experimental study investigated shockwaves and vortex rings from different geometry shock tunnels from formation at the tunnel opening to head on collision with another similarly formed vortex ring using schlieren imaging and statistical analysis. The velocity of the incident shockwave was found to be consistent across all four shock tunnel geometries, which include circle, hexagon, square, and triangle of the same cross-sectional area. The velocity was 1.2 ± 0.007 …

Design And Simulation Of A Utility Oilfield Flare In Iraq/Kurdistan Region Using Cfd And Api-521 Methodology, Ahmed A. Maaroof, Joseph D. Smith, Mohammed H.S. Zangana

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper aims at reviewing and analyzing the operation and design of a utility flare in an oilfield in the Iraq/Kurdistan region. The flare supports a gas separation unit that separates 100 MMSCFD of natural gas from other liquid compounds in petroleum refining. The actual flare dimensions are 50 m high and 0.6 m diameter and works in summer where the crosswind speed is 9 m/s and a flow of 1.2 MMSCFD of treated natural gas is flaring through it. At the beginning, the flare design was performed using the API-521 recommended approach based on full operating capacity of the …

Development And Characterization Of Coal-Based Thermoplastic Composite Material For Sustainable Construction, Haibin Zhang, Wenyu Liao, Genda Chen, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The exploitation of coal and the disposal of waste plastic present significant environmental and economic challenges that require sustainable and profitable solutions. In response, we propose a renewable construction composite material of coal-based thermoplastic composite (CTC) that can be made from low-grade coal and plastic waste. We developed and tested the hot-press fabrication method for this CTC, using coal with a maximum particle size of 4.75 mm and recycled high-density polyethylene (HDPE). The effects of the coal fraction (50–80 wt.%) on compressive properties, thermal properties, microstructure, and ecological and economic efficiencies of the CTC were investigated. Test results revealed that …

Friction And Texture Equipment Correlation Study, David Hacker, Kean H. Ashurst Jr., Clark Graves

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet’s (KYTC) foremost goal is building and maintaining a safe road network. To accomplish this goal, KYTC needs reliable pavement friction and macrotexture data, both of which influence road performance and safety. KYTC currently measures fiction using a lock-wheel skid tester (AASHTO T 242), however, the agency has not been able to collect data at the network level due to equipment and personnel limitations. In 2020 the Cabinet commissioned a study to collect friction and macrotexture data. Investigators used a sideway-force coefficient routine investigation machine (SCRIM) (AASHTO TP 143) to measure friction. To understand the performance of …

Laser-Induced Forward Transfer (Lift) Based Bioprinting Of The Collagen I With Retina Photoreceptor Cells, Md Shakil Arman, Ben Xu, Andrew Tsin, Jianzhi Li

Manufacturing & Industrial Engineering Faculty Publications

This study focuses on the 3D bioprinting of retina photoreceptor cells using a laser-induced forward transfer (LIFT) based bioprinting system. Bioprinting has a great potential to mimic and regenerate the human organoid system, and the LIFT technique has emerged as an efficient method for high-resolution micropatterning and microfabrication of biomaterials and cells due to its capability of creating precise, controlled microdroplets. In this study, the parameters for an effective femtosecond laser-based LIFT process for 3D bioprinting of collagen biomaterial were studied. Different concentrations of collagen I solutions were tested and 0.75 mg/ml to 1 mg/ml collagen Ⅰ was identified as …

Effect Of Transverse Post-Tensioning On Moment Distribution Between Channel Girders, William Eubanks

All Theses

This thesis investigates the strength of prestressed concrete channel girders used

in bridges in South Carolina and how to improve their load distribution. The specimens

are 30 feet in length, 33 inches wide and 17 inches deep. South Carolina has 377 bridges

containing prestressed concrete channel girders and many of these bridges received a

poor load rating in a recent load rating project conducted by the South Carolina

Department of Transportation (SCDOT). The research included flexural testing of seven

individual channel girders and load distribution tests of three transversely post-tensioned

channel girders. Individual flexural testing was done to determine the …

Performance Modeling Of Inline Compression With Software Caching For Reducing The Memory Footprint In Pysdc, Sansriti Ranjan

All Theses

Modern HPC applications compute and analyze massive amounts of data. The data volume is growing faster than memory capabilities and storage improvements leading to performance bottlenecks. An example of this is pySDC, a framework for solving collocation problems iteratively using parallel-in-time methods. These methods require storing and exchanging 3D volume data for each parallel point in time. If a simulation consists of M parallel-in-time stages, where the full spatial problem has to be stored for the next iteration, the memory demand for a single state variable is M ×Nx ×Ny ×Nz per time-step. For an application simulation with many state …

A Study Of 5g Cellular Connectivity To Unmanned Aerial Vehicles, Jackson Murrin

All Theses

The market of unmanned aerial vehicles (UAVs) has seen significant growth in the past ten years on both the commercial and military sides. The applications for UAVs are endless and options by manufacturers allow users to modify their drones for their specific goals. This industry has opened up the excitement of piloting vehicles in the air, photography, videography, exploration of nature from a different point of view and many other hobbies assisted by the emergence of UAVs. The growth of this industry coincides with the roll out of new 5G cellular network technology. This upgrade in cellular network infrastructure allows …

Generalizable Deep-Learning-Based Wireless Indoor Localization, Ali Owfi

All Theses

The growing interest in indoor localization has been driven by its wide range of applications in areas such as smart homes, industrial automation, and healthcare. With the increasing reliance on wireless devices for location-based services, accurate estimation of device positions within indoor environments has become crucial. Deep learning approaches have shown promise in leveraging wireless parameters like Channel State Information (CSI) and Received Signal Strength Indicator (RSSI) to achieve precise localization. However, despite their success in achieving high accuracy, these deep learning models suffer from limited generalizability, making them unsuitable for deployment in new or dynamic environments without retraining. To …

Children First: Women’S Perspectives On Evacuation At Fuego Volcano And Implications For Disaster Risk Reduction, Beth A. Bartel, Ailsa K. Naismith

Michigan Tech Publications

As major drivers of behavior during crisis, cultural norms influence how disasters differentially affect people of different genders. Cultural gender norms also impact how authorities and at-risk populations approach disaster risk reduction strategies. At Fuego volcano, Guatemala, we applied qualitative methods to investigate women’s experiences of the evacuation process after a paroxysmal eruption on 7–8 March 2022. While participants’ experiences and decisions varied, we identified how gender influences evacuation dynamics within communities at Fuego volcano, including who evacuates and who decides at the community and household levels. We find that communities prioritized women for evacuation with the children and elderly …

Combined Behavioral And Engineering Approach To Preventing Highway Fatalities, Benjamin Blandford, Reginald Souleyrette, Caitlin N. Pope, Tony Fields, Erin Lammers-Staats

Kentucky Transportation Center Research Report

Traditional, single-discipline highway safety approaches can be augmented through multidisciplinary approaches that consider both engineering and behavioral interventions (e.g., education, enforcement, public outreach campaigns). Leveraging a systems-based conceptual framework of roadway safety, multiple forms of statistical and geospatial analysis, and SPF modeling and network screening, this report proposes and demonstrates methods for unpacking the influence of behavioral-related factors on crash occurrences and outcomes. The primary focus is on behaviors targeted in the Strategic Highway Safety Plan — aggressive driving, distracted driving, impaired driving, and driving without proper restraint (i.e., seatbelts). Based on application of these methods, the report highlights areas …

Evaluating The Use Of A Near-Miss Reporting Program To Enhance Employee Safety Performance, Gabriel Dadi, Farshid Taherpour, Seth Atkins, Ashtarout Ammar, Jon Wilcoxson

Kentucky Transportation Center Research Report

Using safety incidents and crashes to improve safety performance is an outdated and reactive practice in safety and health programs. One component of a modern approach to safety is a near-miss reporting program. This type of program tracks close calls or near misses that do not result in an incident or crash, but which often can be an early indicator that one may happen. While most construction companies have implemented some methods for reporting near-miss events, many agencies, such as the Kentucky Transportation Cabinet (KYTC), struggle getting employees to report near misses. To fill this gap, potential factors that result …

Innovative Methods To Strengthen Internal Kytc Communications, P. Gayle Marks, Jeff Jasper

Kentucky Transportation Center Research Report

Communication is the linchpin of every organization. Poor communication leads to inefficiencies, frustration among staff, and employee disaffection and disengagement. Although some state transportation agencies have adopted comprehensive strategic plans for internal communications, many have taken a more piecemeal approach, with some Offices and units (e.g., incident management) developing their own plans that apply only to their operations. The latter approach is less than ideal because establishing a comprehensive communications plan provides an organizing framework for all communications within an organization and is critical for uniting staff around a shared sense of purpose and equipping them with the tools they …

Facilitated Identification Of Kytc Performance Measures, Candice Wallace, Jon Wilcoxson

Kentucky Transportation Center Research Report

Federal and state government agencies are embracing performance management as a means to (1) justify the use of tax dollars and (2) monitor and report program accomplishments. The Kentucky Transportation Cabinet’s (KYTC) efforts to fold Transportation Performance Management (TPM) into its business processes and workplace culture required training that would educate personnel about TPM’s benefits, objectives, and activities. After reviewing training resources on performance management from FHWA, NHI, AASHTO, and state DOTs, Cabinet leadership concluded that their emphasis on federal requirements was not exactly what KYTC was looking for in a training program. Instead, KYTC wanted a training program that …

A Portable, Low Power Radiation Detection And Identification System For High Count Rate, Long Term Monitoring, Samuel J. Murray

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This dissertation presents the design of a novel radiation detection and identification system that can operate continuously over a period of 8 days while detecting at 30,000 counts per second, consuming a total of 11 mW. The entire system is highly integrated, containing a gamma ray detector, a high voltage detector power supply, and a multichannel analyzer (MCA) system-on-a-chip (SoC), which are all combined into a compact form using a multi-level, configurable printed circuit board design. The MCA SoC, fabricated using a 65 nm CMOS technology, features two enabling resources to allow low power detections at high count rates for …

Seek And Classify: End-To-End Joint Multi-Signal Detection And Classification Using Deep Learning, Prashant Subedi

School of Computing: Dissertations, Theses, and Student Research

The rise in the use of wireless communication has led to the problem of spectrum scarcity in licensed bands. The popularity of Internet of Things (IoT) requires innovative solutions that maximize the use of available spectrum to support the increasing number of connected devices. This thesis tackles two significant problems in wireless communication: the need for efficient spectrum sensing techniques and the scarcity of large, diverse raw in-phase (I) and quadrature (Q) datasets.

The ability to detect and classify modulation of the signals efficiently can enable a cognitive radio to monitor the spectrum activity in real time and utilize unused …

Investigation Of Cyclic Gaseous Solvent Injection For Enhanced Oil Recovery In Unconventional Formations, Samuel Asante Afari

Theses and Dissertations

Unconventional resources have been known to hold vast quantities of hydrocarbons. However, exploiting the oil and gas they hold was previously challenging due to their low permeabilities. Recent advances in horizontal well drilling and hydraulic fracturing have enabled oil and gas production from these reservoirs, leading to significant increases in energy supply to meet the growing energy demand. However, despite the relative technological success, considerable obstacles persist; oil production from unconventional wells often declines by more than 20% of their initial production rate within the first two years, leaving significant volumes of residual oil trapped in the formations. This overarching …

Cross-Layer Cryptography For Wireless Communication, Hesham Mohammed

Legacy Theses & Dissertations (2009 - 2024)

Spectrum access in the next-generation wireless networks will be congested, competitive, and vulnerable to malicious intents of strong adversaries. This motivates us to rethink secure wireless communication in a zero-trust electromagnetic environment. Classical cryptography is an add-on feature that provides semantic security between trusted partners at higherlayers. However, cryptography ignores cross-layer interaction with physical layer which is required to enhance the secrecy level of the transmitted waveform. Moreover, cryptographic schemes might no longer be secure in the quantum era. Physical layer security (PLS) is introduced as a complement to cryptography, where security is provided in the physical layer using the …

Advancing Selective-Area Doping And Annealing Strategies For High-Conductivity P-Type (Al)Gan System, Vincent Meyers

Legacy Theses & Dissertations (2009 - 2024)

The material properties of the (Al)GaN system, including its high breakdown electric field and high electron mobility, make it a powerful candidate for next-generation high-power and high-frequency electronic devices. The success of this technology is dependent on the ability to form selective-area doped (SAD) p-type regions, which ideally may be accomplished by a combination of straightforward, low-cost ion implantation with Mg, the prevailing p-type dopant, and post-implant annealing. Obtaining high-conductivity p-type GaN following Mg-implantation remains a significant challenge and an area of ongoing research interest. Ion implantation induces lattice damage and creates charged point defects, including the donor-like VN, which …

A Direct Data Approach To Joint 2-D Doa And Frequency Estimation With L-Shaped Array, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a joint two-dimensional dynamic mode decomposition (JTDDMD) approach to estimate the azimuth angle, elevation angle, and frequency for multiple narrowband sources using the L-shaped array. According to the placement position of different coordinate axes of the receiving antenna in the array, i.e., x- or z-axis, the received signal is divided into two datasets. Two-dimensional dynamic mode decomposition (TDDMD), the sub algorithm of JTDDMD, is used twice to deal with these two datasets separately. Through the analysis of the x-axis subarray received signal using TDDMD, the electrical angle in the x-direction and frequency are obtained with automatic pairing. …

Spectral Broadening Effects On Pulsed-Source Digital Holography, Steven A. Owens, Mark F. Spencer, Glen P. Perram

Faculty Publications

Using a pulsed configuration, a digital-holographic system is setup in the off-axis image plane recording geometry, and spectral broadening via pseudo-random bit sequence is used to degrade the temporal coherence of the master-oscillator laser. The associated effects on the signal-to-noise ratio are then measured in terms of the ambiguity and coherence efficiencies. It is found that the ambiguity efficiency, which is a function of signal-reference pulse overlap, is not affected by the effects of spectral broadening. The coherence efficiency, on the other hand, is affected. As a result, the coherence efficiency, which is a function of effective fringe visibility, is …

Localization And Identification Of Emi Sources In Shielding Enclosures Based On A Two-Step Source Reconstruction Method, Zi An Wang, Jun Fa Mao, Li (Lijun) Jun Jiang, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

Localization and identification of unknown electromagnetic interference (EMI) sources in shielding enclosures is a great challenge due to the complex electromagnetic environment. In this work, a two-step source reconstruction method is proposed to address this issue. The actual EMI sources are initially modeled by equally distributed equivalent electric dipoles in the shielding enclosure. Effects of surrounding environments are rigorously incorporated using the numerical Green's function which bridges between the equivalent dipoles and planar scanned tangential magnetic near-field. Next, the initial equivalent sources are downsized via evaluating the contribution of each equivalent dipole. The parameters of remaining equivalent dipoles are updated …

Proceedings Of The 2023 Berry Summer Thesis Institute, University Of Dayton. University Honors Program

Proceedings of the Berry Summer Thesis Institute (2013-Present)

Thanks to a gift from the Berry Family Foundation and the Berry family, the University Honors Program launched the Berry Summer Thesis Institute in 2012. The institute introduces students in the University Honors Program to intensive research, scholarship opportunities and professional development. Each student pursues a 12-week summer thesis research project under the guidance of a UD faculty mentor. This contains the product of the students' research.

Contents:

• “How Porous Materials Affect the Boundary-Layer Transition of Hypersonic Flight Vehicles” (Megan C. Sieve)
• “Ultra-Stretchable, Self-Healing, DLP 3D-Printed Elastomers for Damage-Resistant Soft Robots: A Review” (Robert M. A. Drexler)
• “Extrapolation of Scalar …

Magnesium-Based Nanocomposites: A Review From Mechanical, Creep And Fatigue Properties, S. Abazari, A. Shamsipur, H. R. Bakhsheshi-Rad, J. W. Drelich, J. Goldman, S. Sharif, A. F. Ismail, M. Razzaghi

Michigan Tech Publications

The addition of nanoscale additions to magnesium (Mg) based alloys can boost mechanical characteristics without noticeably decreasing ductility. Since Mg is the lightest structural material, the Mg-based nanocomposites (NCs) with improved mechanical properties are appealing materials for lightweight structural applications. In contrast to conventional Mg-based composites, the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability. The present article reviews Mg-based metal matrix nanocomposites (MMNCs) with metallic and ceramic additions, fabricated via both solid-based (sintering and powder metallurgy) and liquid-based (disintegrated melt deposition) technologies. It also reviews strengthening models and mechanisms that …

The Influence Of Diversity Dimensions On Student’S Collaboration Success: What It Means For Workforce Development In Manufacturing, Oyinkansola Adeite

All Theses

Manufacturing productivity is measured by labor productivity which is the hourly output of the manufacturing economy. The recent reduction in productivity numbers by the United States Bureau of Labor Statistics emphasizes the need for workforce development. With globalization and technological advancements, diversity has emerged as a critical aspect for the workplace. By encompassing dimensions such as education, race, and age, diversity creates a tapestry of unique perspectives and experiences. This study’s aim is to figure out the effect of a diversity dimension on team performance using intelligent systems, and in addition, if extra dimensions of diversity further impact team performance. …

Multiphysics Diesel Aftertreatment System Modeling For Reduced Emissions From Hybrid Electric Heavy-Duty Powertrains, Uday Srivastav

All Theses

Hybridization of heavy-duty on-road vehicles presents an opportunity to significantly reduce internal combustion engine emissions in real-world operation. These gains can be realized through the coordination of the electric drive, engine, and aftertreatment systems. Accurate Multiphysics models of all powertrains sub-systems are required to achieve the goal of reduced emissions. This research aims to develop a model of a highly complex diesel engine aftertreatment system. This study focuses on utilizing transient data for calibration and validation of the aftertreatment system and reducing the run time when compared to real-time experiments. The calibration focuses on two physical phenomena, thermal behavior and …

Machine Learning-Based Seismic Damage Assessment Of Residential Buildings Considering Multiple Earthquake And Structure Uncertainties, Xinzhe Yuan, Liujun Li, Haibin Zhang, Yanping Zhu, Genda Chen, Cihan H. Dagli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Wood-frame structures are used in almost 90% of residential buildings in the United States. It is thus imperative to rapidly and accurately assess the damage of wood-frame structures in the wake of an earthquake event. This study aims to develop a machine-learning-based seismic classifier for a portfolio of 6,113 wood-frame structures near the New Madrid Seismic Zone (NMSZ) in which synthesized ground motions are adopted to characterize potential earthquakes. This seismic classifier, based on a multilayer perceptron (MLP), is compared with existing fragility curves developed for the same wood-frame buildings near the NMSZ. This comparative study indicates that the MLP …

Spectral Characterization Of Fouled Railroad Ballast Using Hyperspectral Imaging, Eberechi Ichi, Sattar Dorafshan

Civil Engineering Faculty Publications

The presence of fouling contamination in railroad ballast is a growing concern that causes deterioration, poor drainage functionality, and early failure of railroad components. Evaluation and characterization of fouled ballast are crucial for determining and monitoring fouling content (FC) and moisture content (MC) in ballast. However, human inspection, destructive testing, filed sampling, and most available nondestructive evaluation methods (NDE) for inspection purposes pose safety risks, undermine the stability of the railroad substructure, or provide limited information about the condition of the ballast. This study presents the results of the spectral characterization of laboratory ballast samples using hyperspectral imaging (HSI) sensor. …

Visual Complexity Of The Time-Frequency Image Pinpoints The Epileptogenic Zone: An Unsupervised Deep-Learning Tool To Analyze Interictal Intracranial Eeg, Sarvagya Gupta

Graduate Masters Theses

Epilepsy, a prevalent neurological disorder characterized by recurrent seizures, continues to pose significant challenges in diagnosis and treatment, particularly among children. Despite substantial advancements in medical technology and treatment modalities, localization of the part of brain that causes seizures (Epileptogenic Zone) remains a difficult task. Intracranial EEG (iEEG) is often used to estimate the epileptogenic zone (EZ) in children with drugresistant epilepsy (DRE) and target it during surgery. Conventionally, iEEG signals are inspected in the time domain by human experts aiming to locate epileptiform activity.

Visual scrutiny of the iEEG time-frequency (TF) images can be an alternative way to review …

Distributed Cooperative Control Of Multiple Uavs With Uncertainty, Shihab Ahmed, Wenjie Dong

Electrical and Computer Engineering Faculty Publications

This paper considers the formation flying of multiple quadrotors with a desired orientation and a leader. In the formation flying control, it is assumed that the desired formation is time-varying and there are the system uncertainty and the information uncertainty. In order to deal with different uncertainties, a backstepping-based approach is proposed for the controller design. In the proposed approach, different types of uncertainties are considered in different steps. By integrating adaptive/robust control results and Laplacian algebraic theory, distributed robust adaptive control laws are proposed such that the formation errors exponentially converge to zero and the attitude of each quadrotor …