Engineering Commons^™

Quantifying Extreme Events: Applications Of Probabilistic Methods To Quantify Riverine And Coastal Flood Dynamics In South Carolina And Neighboring Coastal Communities, Ryne Phillips

Theses and Dissertations

Extreme flood events have been persistent throughout history and have challenged human populations around the globe. Over time, scientists and engineers have developed tools and technology to support flood risk management. Most, if not all, of these tools rely on some form of the field of stochastic hydrology. Stochastic hydrology is a broad discipline, but the overarching principle is to use statistical and data-driven techniques to develop an understanding of one or more hydrologic variables (e.g., flood flow or peak storm tide). However, the need for large sample sizes of data that offer insight into all possible combinations of outcomes …

Control Optimization And Adaptive Tuning Of Droop Controlled Systems For Dc Bus Stability Via Terminal Impedance Shaping, Andy Wong

Theses and Dissertations

Many traditional AC systems have been moving towards DC in recent decades due to advancements in power electronics and semiconductor devices. DC power distribution systems, such as DC microgrids, have become increasing popular due to energy efficiency, resiliency, and renewable energy integration. However, with such systems which commonly utilize droop control, comes an issue of system stability due to the interconnection of multiple feedback-controlled converters to a common bus. To combat this issue, this thesis proposes a control optimization and adaptive tuning approach for maintaining DC bus stability and dynamic performance of droop controlled systems. First, a terminal impedance model …

Multidimensional Simulation Of Cool Diffusion Flame, Ejaz Ahmed

Theses and Dissertations

Understanding the behavior of spherical cool diffusion flames in microgravity conditions is crucial for advancing combustion research. This knowledge has significant implications for both fundamental science and practical applications, such as spacecraft fire safety and the development of advanced, high-efficiency engines that benefit from low-temperature chemistry. Spherical cool diffusion flames are typically characterized by peak temperatures between 500 and 1000K and are often followed by the radiative extinction of a hot flame. Some low-temperature ignitions can sustain indefinitely at around 700K, leading to chain-branching pathways that produce intermediate species such as C2H4, H2O2, HO2, CH2O, CH3O, and HCO. In some …

Accelerating Numerical Modeling And Optimization Of Structural Mechanical Systems, Fatemeh Hashemian

Theses and Dissertations

This research proposal presents Bayesian optimization and reduced order modeling methods to accelerate numerical analysis and design of structure mechanical system. First, a holistic framework of Bayesian optimization (BO) based on parameterized numerical models and genetic algorithm-guided adaptive sampling is developed to automate and accelerate the design of a front-loading washing machine. The research aims to address challenges associated with the model parameterization and global optimization and design. A multibody dynamics model of the washing machine incorporating a set of 9 key design variables is developed. The design variables are implemented to enable automated modifications of the dynamics model for …

Applications Of Catalytic Ammonia Chemistry: From Low-Pressure Ammonia Synthesis To The Decomposition Of Tritiated Ammonia As A By-Product Of Magnetically Confined Nuclear Fusion, Jennifer Kules Naglic

Theses and Dissertations

Ammonia is the 2nd most produced chemical in the world with vital importance for its use in fertilizer as the global population has grown in accordance with the industrialization of NH3. While 80% of NH3 produced goes to fertilizer, it has gained attention recently as a hydrogen storage and transportation vessel. Industrially, NH3 is produced at high temperatures and pressures which in turn require high electrical input. Turning to a green NH3 cycle with low temperature and pressure membrane reactors for both NH3 synthesis and decomposition would allow for much lower energy input as well as a renewable energy to …

Geometrically Exact Beam Theory For Gradient-Based Optimization, Taylor Mcdonnell, Andrew Ning

Faculty Publications

Decades of research have progressed geometrically exact beam theory to the point where it is now an invaluable resource for analyzing and modeling highly flexible slender structures. Large-scale optimization using geometrically exact beam theory remains nontrivial, however, due to the inability of gradient-free optimizers to handle large numbers of design variables in a computationally efficient manner and the difficulties associated with obtaining smooth, accurate, and efficiently calculated design sensitivities for gradient-based optimization. To overcome these challenges, this paper presents a finite-element implementation of geometrically exact beam theory which has been developed specifically for gradient-based optimization. A key feature of this …

Characteristics Of Pyrolysis Products Of California Chaparral And Their Potential Effect On Wildland Fires, Mahsa Alizadeh, David R. Weise, Thomas H. Fletcher

Faculty Publications

The aim of this study was to investigate the pyrolysis of selected California foliage and estimate the energy content of the released volatiles to show the significance of the pyrolysis of foliage and its role during wildland fires. While the majority of the volatiles released during the pyrolysis of foliage later combust and promote fire propagation, studies on the energy released from combustion of these compounds are scarce. Samples of chamise (Adenostoma fasciculatum), Eastwood’s manzanita (Arctostaphylos glandulosa), scrub oak (Quercus berberidifolia), hoaryleaf ceanothus (Ceanothus crassifolius), all native to southern California, and sparkleberry …

Derivative Propagation Through Vortex Particle Method Simulation, Eric Green, Andrew Ning

Faculty Publications

Automatic differentiation (AD) is a powerful tool for evaluating numerical derivatives. In particular, reverse-mode AD provides numerical gradients in a way that is insensitive to the number of input variables. This makes reverse-mode AD well-suited for solving large optimization problems. However, reverse-mode AD has a particularly large associated memory cost because most intermediate values in operations need to be cached. This is problematic for large problems such as aerodynamics simulations, though, since the memory requirements can quickly become impractical. The solution implemented in this work is to provide analytic pullback expressions for functions for which many of the intermediate values …

Trajectory Optimization Of Evtol And Conventional Aircraft: A Comparative Analysis Of Vortex Particle Method And Vortex Lattice + Blade Element Momentum Theory, Andrew Tagg, Ryan Anderson, Cibin Joseph, Andrew Ning

Faculty Publications

Trajectory optimization of aircraft transition maneuvers can significantly influence the design of these systems, particularly when making decisions about aircraft geometry, propulsion sizing, and control system design. This paper presents the trajectory optimization of air vehicles including electric vertical takeoff and landing (eVTOL) as well as conventional aircraft. The study evaluates the influence of fidelity in trajectory design by comparing the use of two aerodynamic methods in the context of trajectory optimization. The mid-fidelity method utilizes a vortex lattice method (VLM) to model lifting surfaces while employing blade element momentum theory (BEMT) to model rudimentary rotor-wing interactions. The high-fidelity approach …

Additively Manufactured Flexible Piezoelectric Wave-Based Multifunctional Sensor, Rishikesh Srinivasaraghavan Govindarajan

Doctoral Dissertations and Master's Theses

The demand for acoustic wave-based sensors has rapidly increased in the aerospace, chemical, gas, and biological fields due to their versatility in sensing measurands. This study aims to develop a flexible piezoelectric sensor exhibiting enhanced piezoelectric properties using additive manufacturing techniques that can detect mechanical strains and gas or volatile organic compounds (VOCs) by incorporating functional material into the sensing layer. This research explores piezoelectric substrate fabrication through diverse additive manufacturing techniques, including new material development made of polymer/nano-fillers with electrodes that are filled using different printing techniques. Notably, the design of the interdigital transducer (IDT) in the piezoelectric sensor …

Dynamic Metabolic Flux Analysis Amidst Data Variability: Sphingolipid Biosynthesis Case Study In Arabidopsis Thaliana Cell Cultures, Abraham Boluwatife Osinuga

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Sphingolipids are pivotal for plant development and stress responses. Growing interest has been directed towards fully comprehending the regulatory mechanisms of the sphingolipid pathway. In this study, we explore its de novo biosynthesis and homeostasis in Arabidopsis thaliana cell cultures, shedding light on fundamental metabolic mechanisms. Employing ¹⁵N isotope labeling and quantitative dynamic modeling approach, we obtained data with notable variations and developed a regularized and constraint-based Dynamic Metabolic Flux Analysis (r-DMFA) framework to predict metabolic shifts due to enzymatic changes. Our analysis revealed key enzymes such as sphingoid-base hydroxylase (SBH) and long-chain-base kinase …

Exploring Performance-Based Contracts: A Good Option To Address Long-Term Road Maintenance In California?, Maria Calahorra-Jimenez, Richard Poythress

Mineta Transportation Institute

Performance-based contracts (PBCs) used in road maintenance provide flexibility for considering new materials, design, and technology to achieve predetermined performance targets. Several states in the U.S. have already used these types of contracts in road maintenance, and their experience can inform the use of PBCs in California. The objectives of this research are twofold. First, identify the benefits and challenges of PBCs compared to traditional contracts. Second, explore the main aspects of PBCs implementation for road maintenance and relate them to California's context. To this end, deductive-inductive content analysis was conducted on 84 peer-reviewed articles published between 1998 and 2023. …

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: 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.

A Feasibility-Preserved Quantum Approximate Solver For The Capacitated Vehicle Routing Problem, Ningyi Xie, Xinwei Lee, Dongsheng Cai, Yoshiyuki Saito, Nobuyoshi Asai, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

The Capacitated Vehicle Routing Problem (CVRP) is an NP-optimization problem (NPO) that arises in various fields including transportation and logistics. The CVRP extends from the Vehicle Routing Problem (VRP), aiming to determine the most efficient plan for a fleet of vehicles to deliver goods to a set of customers, subject to the limited carrying capacity of each vehicle. As the number of possible solutions increases exponentially with the number of customers, finding high-quality solutions remains a significant challenge. Recently, the Quantum Approximate Optimization Algorithm (QAOA), a quantum–classical hybrid algorithm, has exhibited enhanced performance in certain combinatorial optimization problems, such as …

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. …

Engine Performance Of An Electric Airplane With Partial Battery Capability, Hannah Yasmine Scrivens

Theses and Dissertations

As electric aircraft are developed and certified, knowledge of electric aircraft performance during complete or partial battery failures can be useful to determine an aircraft’s limitations and capabilities of completing an emergency landing, especially during takeoff and low-altitude climbs, as well as fully characterizing the potential aircraft performance. The results of this research will be useful in developing regulations and procedures pertaining to energy reserves and emergencies. This paper presents the results of a Pipistrel electric airplane climb power ground test that was conducted by the author and Florida Tech faculty. In the test, one of the airplane’s batteries was …

Patient-Specific Hemodynamic Modeling For Optimizing Left Ventricular Assist Device And Right Heart Health, Holly Felice Grant

Theses and Dissertations

LVAD speed optimization is essential for efficient LVAD therapy and to minimize complications. However, the ideal LVAD speed is unknown and must be tailored for each patient. The interplay between the LVAD, systemic, and pulmonary circulations is critical and should be considered during optimization. A computational hemodynamic model that can be tailored for each patient may provide clinicians with useful guidance and reduce the need for repeated invasive studies. This study sought to customize and evaluate a patient-specific LVAD hemodynamic optimization model.

We conducted a retrospective analysis on 25 patients implanted with HM3 and who underwent right heart catheterization (RHC) …

Evaluating The Influence Of Evtol Pilot Interface Visual Density And Information Density On Pilot Situation Awareness, Workload, And Search Performance, Bhoomin Bhupendrabhai Chauhan

Theses and Dissertations

The purpose of the current study was to investigate the influence of levels of visual density (VD) and information density (ID) of an electrical vertical take-off and landing (eVTOL) aircraft pilot interface on pilot situation awareness (SA), workload, and search performance. An eVTOL aircraft is a novel aircraft design that is able to perform vertical take-off and landing similar to a rotorcraft and transition to a forward flight, similar to a fixed-wing aircraft. These aircraft are envisioned to operate in urban environments at lower altitudes, necessitating efficient, clear, and concise pilot interfaces to ensure safety and operational effectiveness. The study …

An Integrated Space Test Lexicon: A Taxonomy For The Integrated Test And Evaluation Of Space Systems, Stephen K. Tullino, Andrew S. Keys, Robert A. Bettinger, Amy M. Cox, David R. Jacques

Faculty Publications

The proposed Integrated Space Test Lexicon is intended to amalgamate the numerous definitions of integrated (IT or IT&E), development test (DT or DT&E), and operational test (OT or OT&E) into unified, service-wide definitions, aligned with the Space Test Enterprise Vision. Refining such definitions will help distill the core characteristics of these fundamental test types to first identify space system activities composing what is traditionally known as DT and OT, then to provide a means of how these activities fit into the IT paradigm and support space system development. In forging a common understanding of how DT and OT support space …

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’. …

Process Modeling Of Composites For Automated Fiber Placement, Von Clyde Jamora

Mechanical & Aerospace Engineering Theses & Dissertations

Fiber-reinforced composites are available in various material systems, each requiring specific manufacturing techniques to exploit their unique properties fully. Systems such as woven fabrics and preimpregnated fibers employ distinctive methods to harness these properties effectively. For instance, non-crimp fabrics (NCF) use high-pressure resin transfer molding and prepregs, like IM7-8552, use manufacturing method called automated fiber placement (AFP). However, these manufacturing processes often introduce deposition features that can evolve into defects. Their occurrence and impact on morphology must be predicted using experimentally informed finite element models. The research began with compaction experiments on NCF fabric, leading to the development of a …

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 …

Adopt: An Environmentally-Friendly System For Alerting Drivers To Occluded Pedestrians Traffic, Abrar Abdulrahman Alali

Computer Science Theses & Dissertations

The emergence of sensing technologies and vehicular communications has brought significant opportunities for enhancing pedestrian safety on city streets. However, existing solutions rely on costly technologies such as computer vision and trajectory prediction to detect crossing pedestrians, while they have limits in detecting pedestrians who are occluded by parked cars. Despite the presence of collaborative perception by surrounding vehicles and infrastructure, there is a notable absence of incorporating existing parked cars themselves due to their insufficiency in detecting pedestrians and communicating with other cars while they are turned off. Furthermore, accommodating pedestrians on streets has been linked to an additional …

T. Boudieri Extract Potentiates The Effects Of Capecitabine Treatment In Human Colon Cancer Cells, Katia Sawaya, Mahmoud Khalil, Ghada Khawaja

BAU Journal - Science and Technology

Resistance to chemotherapy remains a major challenge for colorectal cancer patients worldwide, hence the persistent need to uncover alternative treatments as well as new adjunct therapies in the fight against cancer. Natural extracts constitute an excellent source of bioactive substances that have a promising potential in that regard, with minimal negative side effects. We have previously demonstrated that both the ethanolic as well as the water extracts of Terfezia boudieri, a black desert truffle abundant in and part of the cuisine of the Mediterranean region, have significant antiproliferative effects against colon cancer cells. Our aim in this study was …

A Strategic Framework For Attaining Golden Leed Certification For Resorts, Mohamad Soliman, Hadi Jawad, Mariam Younes, Oussama El Hamaoui, Saadeddine Ramadan

BAU Journal - Science and Technology

The contemporary landscape of engineering is witnessing a pivotal shift towards sustainability, encapsulated in the catchphrase "GO GREEN". This global trend underscores a strategic emphasis on sustainable design, where engineering projects prioritize a delicate balance among environmental, societal, and economic considerations.” However, a persistent challenge in construction projects lies in their tendency to neglect environmental impact, contributing to increased contamination levels. This paper aims to introduce the "Lodge in the Green" project, meticulously aligned with LEED Certification principles. LEED, or Leadership in Energy and Environmental Design, stands as the foremost green building rating system, highlighting its relevance in contemporary sustainable …

Artificial Intelligence For Authentication Through Mental Profiling Technique, Nawaf Mazloum, Christine Abou-Saleh, Hassan Mazloum, Charles Anosike

BAU Journal - Science and Technology

A new approach to user authentication using mental profiling saw light, which is a technique that involves measuring an individual's cognitive abilities and psychological traits to create a unique profile, using Artificial Intelligence techniques. These profiles can then be used to identify users securely and efficiently, even in the presence of sophisticated attacks, by harnessing AI-driven systems for mental profile creation and user authentication.

After reviewing the existing literature on authentication and mental profiling, it presents a new mental profiling test that is specifically designed for authentication purposes. The test was evaluated on a sample of 100 users, and results …

An Experimental Study On The Effect Of Salt And Sugar Combination On Mortar Properties, Lelian Elkhatib, Jamal Khatib, Abbas Hassan, Mohammad Kassem, Adel Elkordi

BAU Journal - Science and Technology

The most important engineering material nowadays, used in construction is concrete. Concrete consists mainly of sand, cement and aggregates. However, weather conditions play a crucial role in affecting concrete characteristics and its serviceability. Weather conditions could be the reason to delay or accelerate the setting time of the concrete. As a result, and in order to deal with weather conditions and its effect on the setting time of concrete, accelerators and retarders must be added to the concrete mix. This research paper focuses on the impact of the use of salt and sugar on the setting time of concrete. Accelerators, …

An In – Depth Analysis Of Natural Fibers :A Comprehensive Review Of Properties And Performance Characteristics, Abbas Chour, Jamal Khatib

BAU Journal - Science and Technology

The purpose of this research is to investigate the usage of natural fibers in plant-based natural fiber-reinforced cement-based composites for sustainable construction materials. It summarizes research on various fiber kinds, their properties, and their impact on cement-based products, with a focus on renewable possibilities such as flax, jute, ramie, hemp, cotton, sisal, and kenaf. Due to their hydrophilic nature, plant fibers and polymers present compatibility concerns and moisture damage when combined. The paper examines ways for improving durability, such as physical and chemical treatments to improve aging resistance, optimizing binder components, and modifying curing regimens to reduce alkalinity in the …

Final Report - Smart Sounding System For Autonomous Evaluation Of Concrete And Metallic Structures, Anil K. Agrawal, Deepak Kumar

Project IM-3

Recent research by the authors has shown that the sounding, such as chirp signal, can be generated by electronic speakers, and their magnitude and frequency can be controlled. Unlike mechanical impact hammers, the electronic sounding is consistent and can be designed with controlled frequency characteristics to excite defects in concrete decks. Another significant limitation of mechanical impact hammers is that the bottom of a deck cannot be conventionally sounded, and determination of precise location of the damaged area is a challenge. To address these limitations, a “smart sounding system” has been developed that can be used to inspect the underdeck …