Engineering Commons^™

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 …

Zero Dynamics Attacks On Unknown Bilinear Systems: Vulnerability And Detection, Mohammad Aminul Haq

Electrical & Computer Engineering Theses & Dissertations

Critical infrastructure requires a safe and secure operating environment because of its significant impact on society. Its large-scale size and distributed sensors and actuators make it vulnerable to cyber-physical attacks. A zero dynamics attack is a type of cyber-physical attack where an adversary keeps the output of the target constant (classically zero), while forcing some of the internal states to deviate from their nominal values. Most of the existing work in the literature assumes the system dynamics are linear and available to an adversary. The first goal of this dissertation is to show that an adversary can successfully execute a …

Explainable Artificial Intelligence: Methods And Evaluation, Gayane Grigoryan

Engineering Management & Systems Engineering Theses & Dissertations

A wide array of techniques within explainable artificial intelligence (XAI) have been developed to measure the importance of features in machine learning models. A notable portion of these methods draws upon principles of cooperative game theory (CGT), with the Shapley value emerging as a widely used solution concept. Despite the rising prominence of the Shapley value, other promising solutions from cooperative game theory—such as the Nucleolus, Banzhaf power index, Shapley-Shubik power index, and solutions to conflicting claims problems—have been comparatively overlooked, even though they hold significant potential. In this dissertation, multiple XAI methods based on these other CGT solutions are …

Flying Wing Aerodynamic Design And Airbrake Integration, Philip Lawson Mantz

Mechanical & Aerospace Engineering Theses & Dissertations

During the 2022-2023 Academic year, the defense contractor, AeroVironment, tasked the Unmanned Aerial Systems Laboratory at Old Dominion University with designing an autonomous drone platform. A brief summary of the aerodynamic requirements included that the drone should cruise at a target cruise speed of 30m/s, the drone would operate up to an altitude of 1500m and be able to land within a 20m radius of a designated landing spot. The laboratory chose a flying wing model. Additionally, the aircraft would have an airbrake system integrated into the platform.

The aerodynamic requirements were configurated through the use of a ‘constraint diagram’. …

A Kinematic Analysis Of The Shoulder During The Volleyball Attack Using Euler And Helical Axis Methods, Victoria Jolliff

Biomedical Engineering Theses & Dissertations

The shoulder is a complex joint with a wide range of motion, including flexion, extension, abduction, adduction, and internal and external rotation. In volleyball, repetitive overhand movements can cause shoulder overuse injuries. The primary offensive move, the attack, involves the approach, arm cocking, arm acceleration, and follow-through phases. Motion capture analysis and techniques like calculating Euler angles and rotation about a mean helical axis can evaluate shoulder movements. This study aimed to calculate shoulder movements during each phase of the volleyball attack using the Euler angle YXY sequence and the helical axis method. Different attack types, such as cross-court and …

Alternative Applications Of Composite Materials To Reduce Radar Cross Section, Mark Patterson

Mechanical & Aerospace Engineering Theses & Dissertations

The use of carbon nanoparticles and graphene in composite materials has created a foundational shift in enhancing performance across mechanical, thermal, and electrical properties. Such applications are vital in the aerospace industry. However, there has not been such a focus on the material use for reducing radar cross section (RCS). Historically, RCS is minimized by designing sharp geometric shapes to deflect or dissipate the incoming electromagnetic waves away from the receiving antenna. However, these designs are not always optimized for aerodynamics. The goal of this research is to understand the application of composite materials and specifically carbon nanotubes (CNTs) to …

Mesostructure Reconstruction Of Prepreg Platelet Molded Composite With Artificial Intelligence, Richard Larson

Mechanical & Aerospace Engineering Theses & Dissertations

Prepreg platelet molded composites (PPMC) are long, discontinuous fiber reinforced polymer materials. PPMC are an important subcategory of composite materials as they are processible into geometrically complex structures and can be produced via high-throughput manufacturing processes, however they have higher stiffness and strength as compared to traditional discontinuous fiber reinforced polymers. However, there is inherent randomness in the structure of PPMCs and as such, PPMC parts frequently require per part testing that is cost prohibitive.

Herein, a method using artificial intelligence is proposed as a more cost-effective method of inspecting PPMC parts. Different artificial intelligence (AI) architectures are explored to …

Harnessing Social Media For Disaster Response: Intelligent Identification Of Reliable Rescue Requests During Hurricanes, Wael Khallouli

Engineering Management & Systems Engineering Theses & Dissertations

Hurricanes pose a significant threat to both human lives and infrastructure. Decision-makers face substantial challenges during such events, as they must act quickly to address victims’ needs. Social media platforms provide a valuable source for quick and real-time information. Recent hurricane events have shown that people turn to social media to call for help when official communication channels, such as 911, are overwhelmed. However, extracting actionable information from the massive number of messages posted on social media is challenging. Furthermore, verifying social media messages posted by the public is a critical concern for disaster response practitioners, making them hesitant to …

Development Of A Conceptual Framework For Complex System Governance (Csg) Performance Measurement, James Hartwell Rutherford

Engineering Management & Systems Engineering Theses & Dissertations

Within the Complex System Governance (CSG) paradigm, system performance is regulated by nine metasystem governance functions, which provide control, communication, coordination, and integration. However, CSG has lacked a fully developed model or language to richly articulate system performance at a conceptual level. The purpose of this research was to develop a systems theory-based conceptual framework to measure the performance of CSG metasystem governance using an inductive research design.

Although ‘good performance’ may seem like an obvious idea, the current literature on performance measurement across many disciplines and contexts contains vastly inconsistent uses of the word ‘performance.’ Both researchers and practitioners …

Dual Light Emission Of Cssni3-Based Powders Synthesized Via A Mechanochemical Process, Xuan Huang, Xiaobing Tang, Xiyu Wen, Yuebin Charles Lu, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

Lead toxicity has hindered the wide applications of lead halide perovskites in optoelec- tronics and bioimaging. A significant amount of effort has been made to synthesize lead-free halide perovskites as alternatives to lead halide perovskites. In this work, we demonstrate the feasibility of synthesizing CsSnI3-based powders mechanochemically with dual light emissions under ambi- ent conditions from CsI and SnI2 powders. The formed CsSnI3-based powders are divided into CsSnI3-dominated powders and CsSnI3-contained powders. Under the excitation of ultraviolet light of 365 nm in wavelength, the CsSnI3-dominated powders emit green light with a wavelength centered at 540 nm, and the CsSnI3-contained powders …

Design And Verification Of A Planar, Programmable, Compliant Hand For Use In General Open-Loop Constrained Manipulation, Jacob Frye

Master's Theses (2009 -)

Conventional robots are adept at performing tasks where the desired absolute position of the robot's end effector is well defined. However, these robots will struggle with tasks in which the desired position is poorly defined, subject to variation, or determined by contact with a constraint with positional uncertainty. This problem can be solved by introducing compliance to the system, either active or passive. Active compliance uses force feedback to make corrective motions, but is limited in speed and experiences higher contact forces than passive systems. Passively compliant systems are capable of realizing the necessary compliance for a given task but …

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 …

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 …

Electrical And Morphological Investigation Of A Fe(Ii) Based Spin Crossover Complex And Its Composite, Rifat Mahbub

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

Spin crossover (SCO) complexes have unique properties of switching their spin state upon perturbations like temperature, pressure, light, etc. Along with the spin state, different properties vary like structural, electrical, magnetic, optical properties. This enables these materials to be potentially used in various applications like molecular electronics, memory devices, switching devices, sensors and many more. To incorporate spin crossover materials into devices with efficient performance, the electrical behavior needs to be understood. This dissertation aims to investigate the effect of crystal structure on the electrical properties of iron(II) triazole spin crossover complex and how it can be modified for better …

Integrating Remote Sensing And Machine Learning To Determine Past, Current And Future Crop Water Use From The Nubian Sandstone Aquifer System, Moaz Ishag

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The agriculture sector is a significant consumer of water, and sustainable water use begins with monitoring irrigated land. Delineating irrigated land supports decision-makers and promotes the sustainable use of this crucial resource. This study focuses on the Nubian Sandstone Aquifer System (NSAS), the largest aquifers in the world, which spans Egypt, Sudan, Libya, and Chad. The study aims to: 1) quantify the increase in irrigated hectares (both pivot and non-pivot) from 2000-2001 to 2023-2024; 2) identify major irrigated crop types and their water requirements; and 3) quantify groundwater crop water use from the NSAS using remote sensing via the Google …

Jme 4110: Patient Mat Mover, Muhammad Mughal, Seth Gallamore, Gabriel Monte, Marcos Navas Gallardo, Jamie Barvian

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The idea of an improved patient mat mover was suggested to help make the life of patients and their care givers easier. The typical method of using brute force to lift a patient and slide a mat under them can be very challenging and tasking on both the patient and their care giver. It is a large inconvenience in the medical field and makes the process of patient care difficult and uncomfortable. Our value is designing a solution that will eliminate pain and difficulty for both our patients and their nurses/care givers by simplifying patient transport from bed to bed. …

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.

Jme 4110: Washer To Dryer Clothes Transfer Device, Scott Diep, Jared Edwards, Catherine Mcdonnell, Patrick Geldmeier

Washington University / UMSL Mechanical Engineering Design Project JME 4110

For those leading busy lives or facing mobility challenges, this project involve a custom device can transfer clothes from washer to the dryer automatically when the person is not home. This solution eliminates the need to manually move clothes from the washer, preventing formation of mildew, and ensuring that the laundry is fresh and ready to wear when you return.

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: Stand-Up Pedicure Final Report, Heather Burt, Brian Hinkle, Jonathon Riggle, Anna Domingo Garcia

Washington University / UMSL Mechanical Engineering Design Project JME 4110

This project focuses on designing a pedicure device specifically for individuals who struggle with bending down to cut their toenails. While many people may not give this task a second thought, for some, it is a daily challenge. The goal is to create a device that allows users to safely and comfortably cut their toenails without needing to bend down or visit a nail salon, saving them time, effort, and money. This innovative design will cater to those with physical limitations, enabling them to maintain their nail care independently.

Dark Knights: Exploring Resilience And Hidden Workarounds In Commercial Aviation Through Mixed Methods, Riana Steen, James Norman, Johan Bergström, Gitte F. Damm

Aviation Faculty Publications

In this study, the duality of adaptive capacity in aviation safety is examined, where the need for resilience of frontline workers conflicts with the expectations and assumptions of upstream entities, leading to system brittleness. We explore three critical categories: responsibilization, the application of practical wisdom in navigating challenging situations, and the unrecognized sacrifices that accompany adaptation. A qualitative research design is used, using three focus groups consisting of pilots in a European airline, the airline’s safety department, and the respective civil aviation authority. The study's findings reveal i. significant organizational constraint and pressure on pilots, resulting in workarounds, personal playbooks, …

Form Pressure Exerted By Concrete For A Large-Scale Structure: Its Quantification And Physicochemical Interpretation, Tae Yong Shin, Seongho Han, Jin Hyun Lee, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Securing safety in formwork is one of the most important tasks to be carried out in the initial stage of construction. The form pressure exerted by fresh concrete needs to be identified, and it should be retained by a formwork system. A design pressure is given in literature and standards, but for large structures its precise prediction is required through a detailed analysis or a mock-up test. This study reports the lateral form pressure distribution generated by fresh concrete through a series of mock-up tests. The tests are designed considering the placement for nuclear containment structures; 3.4 m tall and …

New Method To Calculate Friction Velocity In Smooth Channel Flows Using Direct Numerical Simulation Data, Harshit Mishra, S. Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, we leverage the direct numerical simulation (DNS) data for closed-channel flow for a range of friction Reynolds number (Reτ∼180-5,000) to develop a new one-point friction velocity method (OPFVM) to calculate friction velocity U∗ in terms of free-surface velocity Um, flow depth h, and kinematic viscosity ν. In contrast to prevalent methods that require several cumbersome near boundary measurements to obtain friction velocity, the OPFVM relies on a single easy-to-measure free-surface velocity measurement. The formulation is used to obtain friction velocity for a closed-channel flow (CCF) DNS regime with Reτ=10,049 and on four open-channel flow (OCF) DNS regimes …

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 …

Increasing Optical Channel Capacity By Integrating Pam4 Modulation With Wavelength Division Multiplexing And Spatial Domain Multiplexing, Swaroopini Harish

Theses and Dissertations

Spatial division multiplexing (SDM) is a technique used in telecommunications and networking to increase data transmission capacity over optical fiber communication channels. This multiplexing technique spatially reuses optical frequencies by allocating different spatial locations for inputs based on their inject angles. The signals travel in a helical pattern within the carrier fiber and exit as concentric rings. SDM enables more efficient utilization of available bandwidth and improved communication performance. In four-level pulse amplitude modulation (PAM4), each symbol represents a combination of four possible signal levels instead of the two levels in binary modulation. The four levels are denoted in different …

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 …

Investigation Of Emissions Characteristics Of Natural Gas Engines With Prechamber Enabled Mixing Controlled Combustion, Johnathan Michael Ronsman

Master's Theses (2009 -)

Increasingly stringent emissions regulations have motivated the exploration of ways to decarbonize the internal combustion engine (ICE). Alternative fuels are of interest as they can easily be implemented with existing infrastructure. Among these alternative fuels, natural gas stands out due to its large abundance and high hydrogen-to-carbon ratio, which can significantly reduce CO2 emissions. Due to its low reactivity, most natural gas engines today are premixed lean burn spark ignited (SI) engines. These engines produce criteria pollutants, such as nitrogen oxides (NOx) and carbon monoxide (CO), but due to their premixed nature, also produce relatively large amounts of unburned methane …