Engineering Commons^™

Machine Learning Approaches To The Exploration Of Ammonia Synthesis Catalysts Utilizing Experimental Data, Rasika Jayarathna

Theses and Dissertations

Traditional heterogeneous catalyst discovery process relies upon human expert-guided experiments based on domain knowledge and human intuition supported by catalyst characterization. However, this process is time and resource-consuming and suffers from human bias. Machine learning (ML) models trained on experimental data have the potential to significantly accelerate this discovery process by guiding experiments to optimize the catalyst performance and increase the understanding of the catalysts. Ammonia synthesis catalysts are a class of catalysts widely investigated in the literature, which has generated decades of experimental data. Moreover, ammonia has been gaining attention since it can be used as a carbon-free next-generation …

Teaching Learning Newsletter Vol 4 Issue 1, Sastra Deemed To Be University

TLC Newsletter

No abstract provided.

React: Recognize Every Action Everywhere All At Once, Naga Venkata Sai Raviteja Chappa, Pha Nguyen, Page Daniel Dobbs, Khoa Luu

Electrical Engineering and Computer Science Faculty Publications and Presentations

In the realm of computer vision, Group Activity Recognition (GAR) plays a vital role, finding applications in sports video analysis, surveillance, and social scene understanding. This paper introduces Recognize Every Action Everywhere All At Once (REACT), a novel architecture designed to model complex contextual relationships within videos. REACT leverages advanced transformer-based models for encoding intricate contextual relationships, enhancing understanding of group dynamics. Integrated Vision-Language Encoding facilitates efficient capture of spatiotemporal interactions and multi-modal information, enabling comprehensive scene understanding. The model’s precise action localization refines joint understanding of text and video data, enabling precise bounding box retrieval and …

Laboratory Evaluation And Field Demonstration Of Cold In-Place Recycling Asphalt Mixture In Michigan Low-Volume Road, Dongzhao Jin, Lei Yin, Lance Malburg, Zhanping You

Michigan Tech Publications

Cold-in place recycling (CIR) is a promising technology for the rehabilitation of asphalt pavements. However, the CIR asphalt pavement constructed in the field often has high air voids due to the presence of moisture during construction, and the moisture susceptibility of the pavement is crucial in determining its service life. Therefore, the objective of this research was to assess the laboratory performance of CIR asphalt mixes under freeze-thaw conditions (The mix prior to being subjected to freezing and thawing is labeled as "dry condition", while the mix that was placed in a refrigerator at –18 °C for 16 h and …

Optical Frequency Domain Reflectometry-Based High-Performance Distributed Sensing Empowered By A Data And Physics-Driven Neural Network, Zhaopeng Zhang, Wei Peng, Osamah Alsalman, Lingmei Ma, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Optical frequency domain reflectometry (OFDR) based distributed strain sensors are the preferred choice for achieving accurate strain measurements over extensive sensing ranges while maintaining exceptional spatial resolution. However, the simultaneous realization of high spatial resolution, high strain resolution, large strain range, and an extended sensing range presents an exceedingly challenging endeavor. In this study, we introduce and experimentally demonstrate a data and physics-driven neural network-empowered OFDR system designed to attain high-performance distributed sensing. In our experiments, we successfully maintained an impressive sensing resolution of sub-microstrain (0.91 µε) alongside a sharp spatial resolution of sub-millimeter (0.857 mm) across a 140-m sensing …

Advance On Rock-Breaking Cutter Steels: A Review Of Characteristics, Failure Modes, Molding Processes And Strengthening Technology, Ying Jiang, Bai Xin Dong, Jun Fan, Feng Qiu, Hong Yu Yang, Shi Li Shu, Fang Chang, Qi Chuan Jiang, Lai Chang Zhang

Research outputs 2022 to 2026

Rock breaking has always been a challenging problem that must be solved in projects such as excavating mountains, drilling wells, and constructing railways. Among the rock-breaking cutter steels, AISI H13 steel and wear-resistant high manganese steel have become the best choices. From the characteristics and failure modes of the two, rock-breaking cutter steels should simultaneously have high strength, high toughness and high wear resistance to avoid short-term fracture/damage and cost increase. Analyzing the problems existing in the molding process of rock-breaking cutter steels such as die casting, forging, and hot stamping, traditional strengthening technologies such as alloying optimization, heat treatment, …

Jme 4110: Better Beach Wagon, Jalen Rhodes, Joshua Peters, Seth Peters, Jevonn Lewis-Harris

Washington University / UMSL Mechanical Engineering Design Project JME 4110

This project aims to add to a current beach wagon and improve effective movement through sand and concrete. Some beach wagons out in the market make it incredibly difficult to navigate through sand, often requiring more effort to push or pull. Some beach wagons solve these issues, such as electric beach wagons and their use of balloon tires; however, they are typically expensive, costing up to $2500.00. With Visionary Solutions’ design, the beach wagon will be able to move smoothly through both terrains (concrete and sand) and will be inexpensive to produce. The materials design includes polylactic acid (PLA) 3D …

Jme 4110: Inflatable Patient Wedge, Thomas Gunsten, Bushra Zaidi, Zachary Howell, Luke Prichard

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The goal of this project was to design, model, and build an inflatable patient wedge, capable of lifting a patient from a laying position to an appropriate sitting position. This system had to be cheap, reliable, and strong enough to lift a wide range of different patients. The design of this project includes repurposed air mattresses, resealed with an epoxy, and shaped into an appropriately angled wedge.

Thermal Hydraulic Analysis For Different Subchannels Of Generic Vver-1200, Mosaddak Ahamed Zahid, Md. Imam Mehedi, Shamsul Arefin Shibly, A. S. Mollah

International Journal of Nuclear Security

The demand for nuclear energy is steadily increasing all over the world. Most nuclear power is used for peaceful applications such as power generation, healthcare, agriculture, food security, industry, and research. One of the primary applications of nuclear energy is the generation of electricity through nuclear power plants based on nuclear reactors. Many developing countries around the world (such as Bangladesh) are moving toward nuclear power plants because they have huge advantages, including low-cost energy, reliable energy sources, zero carbon emissions, and high energy concentration. As a result, the demand for nuclear reactor protection and operational protection of nuclear power …

Deformation Demands And Collapse Performance Of Seismically Detailed Concentrically Braced Frames, Samuel Jablonsky

Master's Theses (2009 -)

Special concentrically braced frames (SCBFs) and ordinary concentrically braced frames (OCBFs) are seismic-force-resisting systems often used in steel building construction. Previous research has shown that lower brace width-to-thickness ratios delay brace fracture during cyclic inelastic loading that is typical during moderate-to-large earthquakes. To ensure adequate seismic performance, SCBF and OCBF brace shapes are thus limited by the highly and moderately ductile width-to-thickness ratio limits, respectively, presented by the American Institute of Steel Construction Seismic Provisions for Structural Steel Buildings. To justify these limits, system-level analysis of SCBFs and OCBFs during high seismic events is needed. This study uses nonlinear response-history …

Emulsion Liquid Membrane (Elm) Enhanced By Nanoparticles And Ionic Liquid For Extracting Vanadium Ions From Wastewater, Qusay Al-Obaidi, Nora Yehia Selem, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Emulsion liquid membrane (ELM) stands out as an extraction process that has drawn much attention due to its promising prospects in industrial wastewater treatment technology. Nevertheless, the pivotal challenge is to reach high membrane stability to overcome the obstacle of applying ELM at the industrial scale. In this study, ELM was boosted by using nanoparticles (superparamagnetic iron oxide (Fe₂O₃)) in the stripping phase (W1) and ionic liquid (1-methyl-3-octyl-imidazolium-hexafluorophosphate [OMIM][PF6) in the oil phase (O) for recovering/extracting vanadium from synthetic wastewater to near completion and at the same time enhancing emulsion stability to be appropriate for industrial …

Induction Vacuum Swing Adsorption Over Magnetic Sorbent Monoliths And Extrudates For Ethylene/Ethane Separation, Khaled Baamran, Usman Shareef, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electrification of adsorption processes is emerging as an adaptable solution for future gas separations. This study develops magnetic sorbent structures for use in induction vacuum swing adsorption (IVSA) process specifically designed for olefin/paraffin separation. Two sorbents, namely Fe₃O₄/ZIF-7 (ethane-selective) and Fe₃O₄/13X (ethylene-selective) were developed and formulated into extrudates (Fe₂₀/ZIF-7-P) and monoliths (Fe₂₀/13X-M), and tested under different regeneration scenarios, including simultaneous and subsequent induction-evacuation, induction only, and evacuation only. The dynamic adsorption results demonstrated that regeneration under subsequent induction-evacuation improves desorption rate and capability. Under this regeneration scenario, Fe …

Development Of A Rule-Based Monitoring System For Autonomous Heavy Equipment Safety, Amirpooya Shirazi

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Roadway construction work zones are constantly exposed to interactions among construction equipment, workers, and vehicles. Furthermore, ensuring safety in these areas is considered a challenging task due to the complexity of the environment. As shown in the rising trend of fatal accidents in roadway work zones, current OSHA regulations in construction safety are insufficient in effectively detecting unsafe situations and mitigating the risks. Furthermore, best practices, such as internal traffic control planning (ITCP), exhibit critical limitations requiring continuous monitoring of active work zones as well as adjustments to the site coordination plans due to the dynamic nature of work zone …

Unmanned Aerial Vehicle (Uav)-Based High-Throughput Phenotyping For Maize Improvement, Eric T. Rodene

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Modern breeding programs rely heavily on efficiently screening large numbers of genotypes for agronomic traits, such as disease resistance, drought tolerance, and yield. Identifying the genetic loci or genes associated with these traits using GWAS or functional analyses will benefit future plant breeding efforts seeking to incorporate these traits into new crop varieties, whether through conventional breeding or gene editing techniques. Unmanned aerial vehicle (UAV)-based image data has been increasingly used for this task, as it allows entire test plots to be quickly and cost-effectively phenotyped. In my research, I have developed methods to improve the accuracy of machine learning …

Growth And Simulation Of Dielectric-Metal Nanoheterostructured Thin Films By Ballistic Deposition, Shawn Wimer

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This thesis is divided into two related topics: the structural and chemical characterization of dielectric-metal nanoheterostructured thin films grown by glancing angle deposition (GLAD) and the results of the simulated growth of films and structures by GLAD with discrete-space and continuous-space Monte Carlo ballistic simulation.

Individual structures comprising films grown by GLAD were investigated by S/TEM and SEM imaging, electron diffraction, and chemical characterization and mapping by EDX. Different intermolecular interactions within and between different materials, including Si, Ag, Au, and ZrO₂, are linked to differences in the shapes of individual materials in heterostructures, the shape of heterostructures …

Laser 3d Printing Of Diamond-Based Composite Materials For Thermal Management Applications, Nada Kraiem

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

With the trend towards miniaturization of electrical equipment and the constant increase in power density in semiconductor devices, efficient heat management has become a major concern for researchers. Indeed, this technological evolution imposes increasingly strict constraints in terms of thermal dissipation, necessitating innovative solutions to ensure better durability and reliability of components. In this context, the use of composite materials offering high thermal conductivity (TC) and low coefficient of thermal expansion (CTE) compared to pure metals has become essential to address overheating issues in electronic components.

The utilization of advanced materials such as diamond (D), with exceptional TC and hardness …

Advancements In Microscale Tensile Testing: A Novel Device For The High Throughput Analysis Of Two-Photon Polymerized Microfibers In Liquid, Grayson D. Minnick

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Two-photon polymerization (TPP) enables the 3D fabrication of micro- and nanostructures from biocompatible materials with high resolutions, reaching into the realm of hundreds of nanometers. Such capabilities are crucial for advancing applications in fields like mechanobiology. As microscale technologies evolve, the precise characterization of material properties becomes increasingly essential. This is especially true for TPP-printed microstructures serving as scaffolds for 3D cell culture and intended for studying the mechanics of tissues. Despite the importance, traditional micro-scale tensile testing methods typically lack scalability and fail to replicate relevant environmental conditions. This dissertation introduces a new device that is specifically designed to …

Influence Of The Work Environment On Workplace Learning Of Undergraduate Engineering Interns, Yashin Brijmohan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Internships are an impactful form of workplace learning that helps undergraduate engineering students acquire and enhance competencies to improve their employability. However, the nuances about what makes an internship successful are not well understood. Furthermore, learning during engineering internships has not been thoroughly researched. Previous literature has mostly focused on internship outcomes, and there is little discussion on how to improve internship experiences to achieve the expected outcomes. Thus, this qualitative study explored the workplace learning environment of internships and how engineering undergraduate students engaged with workplace learning. The study has produced a comprehensive framework that illustrates important factors in …

New Improvements To Defend Against Power Analysis Attacks In Ijtag Access Protocol, Haoran Wei

Computer Science and Engineering Theses and Dissertations

More and more instruments are now integrated on the chip for testing, debugging, monitoring, and post-silicon validation. IEEE Std 1687 (IJTAG) provides efficient access to these instruments. At the same time, techniques for an attacker to steal important data through the IJTAG network have also emerged. To improve the security of the IJTAG network and especially the communication between software and a board, others have proposed a security access protocol with several possible implementations based on an information hiding method. For example, one version of this previously published bidirectional authentication access protocol uses multiple templates to embed keys to improve …

Freezing-Thawing Hysteretic Behavior Of Soils, Jidong Teng, Antai Dong, Sheng Zhang, Xiong Zhang, Daichao Sheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The soil freezing characteristic curve (SFCC) plays a crucial role in investigating the soil freezing-thawing process. Due to the challenges associated with measuring the SFCC, there is a shortage of high-quality or rigorous test results with sufficient metadata to be effectively used for applications. Current researchers typically conduct freezing tests to measure the SFCC and assume a singular SFCC when studying the freezing-thawing process of soils, although limited studies indicated that there is a hysteresis during the freezing and thawing process. In this paper, a series of freezing-thawing tests were performed to assess the SFCC, utilizing a precise nuclear magnetic …

Balloon Borne Gps-Enabled Radiosondes That Enable Simultaneous Multi-Point Atmospheric Sensing With A Single Ground Station, Peter A. Ribbens

Doctoral Dissertations and Master's Theses

Radiosondes are balloon borne atmospheric instruments that are a critical tool for understanding dynamics in the lower layers of the atmosphere. The low-cost radiosondes developed in the Space and Atmospheric Instrumentation Lab have been further developed to improve the system's use as a science-quality atmospheric instrument that is unique in its ability to simultaneously track multiple sondes with a single ground station. Sensors to measure temperature and pressure were added to improve measurements of the atmospheric state. A printed circuit board shield and 3D-printed shell were designed to make mass manufacturing possible. A thermistor-based temperature sensor was developed and tested …

Optimization Of A Plate Beam System For Energy Harvesting Using A Piezoelectric Material, Jose Manuel Almendros Espantaleon

Doctoral Dissertations and Master's Theses

With a continuously growing demand for power, driven by the need to reduce our environmental footprint, this research provides an examination of the potential of energy harvesting with smart materials technology and its practical applications. The energy harvesting system considered here works on generating energy through vibrations of a piezoelectric material beam which will undergo sustained vibrations due to flow of air over its surface. It is assumed that sustained limit cycle oscillations of this system will occur at the flutter velocity. This research creates an optimization framework to obtain the best values of parameters that will result in the …

Exploring A New Conceptual Framework In Aviation Maintenance Incident Reporting Using Natural Language Processing, Christopher P. Braun

Doctoral Dissertations and Master's Theses

In the analysis of human error incidents, human factors specialists predominantly follow two schools of thought in categorization strategies. One is to categorize the operator’s actions by the physical properties of the activity (phenotypes); the other focuses on the cognitive behaviors preceding the incident (genotypes). These categorization strategies are intended to foster an understanding of the events, identify risks, and assist in the implementation of risk reduction interventions. Commercial aviation maintenance presents unique challenges to human factor practitioners in terms of task requirements, working environments, communication modalities, and safety standards. Complex tasks are handed from one shift of personnel to …

Situation Awareness Assessment Of Enhanced Stable Approach Flight Instrument Displays, David J. Hunter

Doctoral Dissertations and Master's Theses

Through the year 2022, runway-related events, including excursions, abnormal runway contact, and runway undershoot and overshoot, were the third leading causes of fatal aircraft accidents. Principal to these runway-related accidents was the presence of an unstable approach. Pilots currently must depend on the timely recall of stable approach criteria stored in long-term memory, application of those criteria against current flight conditions, perception and cognition of deviation from those criteria, and determination of potential courses of action. Such recall is fallible, and challenges to perception and cognition are ever-present.

This study examined whether the presentation of stable approach criteria boundaries and …

Assessing The Impact Of Spacecraft Fragmentation In The Cislunar Region, Marta Lopez Castro

Doctoral Dissertations and Master's Theses

In the last decades, space missions have followed great advancements due to technological improvements and the extensive research developed in the field. Some of these missions are increasingly focusing on satellites orbiting the Moon. The Cislunar region is known to have a higher non-linear chaotic component in the dynamics compared to the low-Earth environment. This research is focused on studying the impact that a satellite explosion has in the Cislunar vicinity. The study is conducted for different periodic orbits that are key destinations for Cislunar traffic. By varying the initial conditions, simulations of explosions at different locations of the orbits …

Studying The Performance Of Object Recognition With Fusion Of Visible Light And Infrared Images With Neural Networks, Plamen Petkov

Doctoral Dissertations and Master's Theses

Neural networks have been used for object detection and recognition in both color and intensity camera images. As the use of infrared cameras, colloquially termed thermal cameras, has increased and costs have decreased, object detection and recognition in infrared camera images have been increasingly studied. An infrared image is treated as an intensity image, just like a grayscale camera image, except the intensity corresponds to infrared radiation instead of visible light. The information provided by these two types of images are different, especially in different lighting and environmental situations, and some types of objects are more easily recognized in visible …

Refinement Of A Regional Storm Surge Mesh For High-Resolution Topographic Representation Of Volusia County, Morgan Harbin

Doctoral Dissertations and Master's Theses

In 2022, Volusia and Flagler Counties of northeast central Florida were impacted indirectly by consecutive Hurricanes Ian and Nicole; the destabilization of dunes and armoring infrastructure caused by Ian left the region susceptible to Hurricane Nicole, which caused unprecedented coastal damage to dunes and seawalls. The extent of damage that occurred within Volusia and Flagler Counties during the 2022 hurricane season, the underrepresentation of this region within sustainability and resilience research, and the ecological, social, and economic value of the geography provide just cause for scientific inquiry of the area’s coastal dynamics. This thesis specifically describes an investigation of Hurricane …

Multisensory System For Probing Scattering Media, Muralidhar Madabhushi Balaji

Electrical Engineering Theses and Dissertations

There are numerous problems in the physical sciences wherein the scattering of light fundamentally limits our ability to perceive and reason about objects within the visual field. Examples include navigation in foggy weather, detecting hidden contraband/explosives, detecting diseased regions in agricultural produce, and detecting tumors within tissue. In all these scenarios, the scrambling of light paths due to scattering reduces the ability to locate embedded objects and identify their spatial or spectral features.

Existing approaches address the challenge by augmenting optical sensing modalities with complementary techniques that do not rely on optical phenomenology, such as Magnetic Resonance Imaging (MRI) or …

Lessons From Developing A Rubric For Evaluating Need Statements On Health Technology Innovation Projects, L. Denend, R. Venook, R. D. Pamnani, K. Sheth, Joseph D. Towles

Engineering Faculty Works

In design-oriented biomedical engineering courses, some instructors teach need-driven methods for health technology innovation that use a “need statement” to reflect a student team’s hypothesis about the most fruitful direction for their project. While need statements are of the utmost importance to the projects, we were not aware of any comprehensive rubric for helping instructors evaluate them. Leveraging resources such as the Biodesign textbook along with input from faculty teaching health technology design at our university, we created a rubric for evaluating the construction of need statements. We then introduced the rubric to undergraduate students in a 3-week intersession course …

Poly(Thioether) Thermosets With Gated Photodegradation, Surabhi Jha

Dissertations

Photodegradable polymer networks are attractive due to the precise spatiotemporal control and large-area applicability of light. Chemical linkages that enable these polymer networks to be photo-responsive, also hinder their applicability in ambient light. Photostable and photodegradable networks have recently been reported to overcome this challenge by combining other stimuli with light for degradation. We report the design of a network that responds to a simultaneous, dual stimulus for photodegradation. We design poly(thioether acetal) networks with benzylidene acetal moieties that are known to undergo β-scission in the presence of free thiols. By blocking these free thiols with a thermally labile protecting …