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Custom Cathode Optimization For Electropolishing Additively Manufactured 316l Stainless Steel, Kasandra Escarcega Herrera

Mechanical Engineering ETDs

Laser powder bed fusion (LPBF) has become increasingly popular for its ability to rapidly manufacture complex metallic parts. However, the surface properties of as-built LPBF parts may degrade overall performance due to tortuous surface features. Consequently, post-processing like electropolishing (EP) to reduce the surface asperities is often needed for LPBF parts to perform as expected. Utilizing experimental and computational approaches, this project aims to more uniformly EP complex shaped parts made from LPBF 316L. For the experimental approach, parts with a three-dimensional T-shape were printed out of 316L stainless steel and EP using an acidic-based and a polyethylene glycol/NaCl-based electrolyte. …

12.02.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Email Address Matters

All of Us Researcher Symposium

Welcome Anya Goldman

Predictive Modeling And Sustainability Assessment Of Hydrothermal Liquefaction Of Seaweeds: A Techno-Economic And Life Cycle Analysis Approach, Micheal O. Asama

Mechanical Engineering Theses

This study presents comprehensive predictive models and an economic and environmental assessment of HTL for converting macroalgae into biofuels and valuable co-products. Predictive models were developed based on experimental kinetic data to simulate batch HTL of brown seaweed, capturing the yields of biocrude, gas, biochar, and water-soluble compounds as functions of key process variables, including temperature, time, pressure, and water-to-biomass ratio. Analysis of Variance (ANOVA) confirmed that temperature and residence time significantly affect biocrude yield, with an optimal yield of 23% achieved at 283°C, 200 bar, 54 minutes, and a 10:1 water-to-biomass ratio. The model’s predictive accuracy was validated with …

Data Intensive Method For Processing Defect Detection And Mitigation For Composites, Deepak Kumar

Doctoral Dissertations and Master's Theses

Composite manufacturing without processing defects is a crucial step in satisfying the production, performance, and quality requirements of composite materials in various industries. Autoclave processing enables manufacturing of high-quality composite parts with excellent mechanical properties, whereas additive manufacturing (AM) offers adaptability to complex designs and streamlined processes. However, each method presents unique challenges; despite the benefits, autoclave processes can still result in processing defects, and AM is particularly susceptible to processing anomalies owing to the novelty of the process. Ensuring the quality and reliability of composite manufacturing is essential to fully capitalize on the advantages offered by both techniques. Artificial …

Traveling-Wave Vibration Control And Comparison Of Individuals With Insomnia And Good Sleepers Using Eeg Spectral Power And Sample Entropy, Joseph T. Lecheminant

Theses and Dissertations

This thesis explores the intersection of whole-body vibration (WBV) and neurophysiological analysis to improve sleep quality and understanding of insomnia. The work is divided into two primary areas: the development of a novel traveling-wave vibration system for sleep enhancement and the analysis of electroencephalography (EEG) metrics in individuals with insomnia versus good sleepers. A vibrating sleep system capable of generating programmable traveling-wave patterns is designed and prototyped. Through iterative development and user trials, the system enables highly controlled mechanical stimulation in the form of traveling-wave vibration. Key advancements include independent amplitude and speed modulation and customizable wave patterns. Simple wave …

An Experimental Investigation Of Signal Processing Techniques For Vibration-Based Structural Health Monitoring In Residential Buildings Subjected To Base Excitation, Fedaa Ali

Electrical Engineering Theses

Coastal regions, particularly in the southeastern United States, are consistently confronted with the ongoing threat of hurricane-induced damage to their buildings. Consequently, there is a pressing need to concentrate efforts on the evaluation and prediction of structural integrity and reliability in such environments. This is paramount for minimizing losses and enhancing public safety in the face of these challenging climatic conditions. Current structural health monitoring systems are typically customized for specific buildings, rendering them excessively expensive and impractical for residential structures. This research presents a comprehensive study of signal processing techniques and damage detection for an economical yet efficient structural …

Cellular Air Quality Sensors With Lora Backchannel A Robust Sensor Suited For Remote Deployment In Harsh Environments, Joseph R. Miera

Theses and Dissertations

Air quality significantly impacts health and overall quality of life, making its measurement essential. However, most affordable air quality devices are designed only for use within WiFi range and cannot handle extreme temperatures, limiting their usefulness for people in remote or extreme environments, such as regions with harsh winter climates. This limitation is concerning, as winter often brings worse air quality due to temperature inversions that trap pollutants and increase fuel burning for heating. Inversion is a problem as close to home as Utah Valley, and as far away as Ulaanbaatar, Mongolia. Most low-cost air quality sensors are not built …

Etherealbreathing: A Holographic Biofeedback Game To Support Relaxation In Autistic Children, Arturo Morales Téllez, Isabel López Hurtado, Franceli L. Cibrian, Monica Tentori

Engineering Faculty Articles and Research

Biofeedback training for box breathing is becoming increasingly accessible due to advancements in consumer-grade breathing sensors. However, there is limited research on their design and applications for specialized populations. This study evaluates a novel biofeedback holographic game, EtherealBreathing, designed to support autistic children. In EtherealBreathing, children practice box breathing to collect virtual elements to maintain the Earth's balance, using a wearable sensor to measure chest expansion for breath detection. A deployment study with 20 autistic children revealed that EtherealBreathing effectively promotes box breathing, leading to better health-related outcomes, such as lowering participants’ heart and respiratory rates than traditional practices. Biofeedback …

The Role Of Customers In Strategic Information Technology (It) Initiatives, Siddharth Aggarwal

Doctoral Dissertations and Projects

This study focused on a small organization in the United States of America. The organization has IT departments that cater to the IT needs of its internal and external customers through IT products and services. Such organizations run full life cycles of product management and product development and often face off with situations to prioritize the use of their limited resources. Ideally, organizations focus on strategic IT initiatives that might be in the company's and its customers' best interest. However, instances occur when IT-driven initiatives lose that focus and might end up diverting resources toward the latest shiny technology and …

An Evaluation Of Features Extracted From Facial Images In The Context Of Accurate Age Estimation⋆, Malik Awais Khan, Aurelia Power, Peter Corcoran, Christina Thorpe

Conference papers

Age estimation by face image recognition can be used in numerous ways with regression models to manage access control, improve security, and guarantee the protection of children online. The approaches used for predicting age—including data selection, cleaning techniques, feature extraction, algorithm choice, and hyperparameter tuning—often struggles with generalization. Furthermore, a lot of methods neglect to specifically address how extracted face features might be used for prediction. To address the lack of racial diversity we acquired a dataset consisting of different races from literature. We also examined the ability of local, global and hybrid facial features to predict ages. Two variants …

Identifying Subject Bias In Wifi-Based Human Activity Recognition Evaluation Methods, Amany Elkelany, Robert J. Ross, Susan Mckeever

Conference papers

WiFi-based Human Activity Recognition (HAR) has emerged as a promising approach for monitoring and analysing human activities in a non-intrusive manner, leveraging WiFi signals for activity classification. Despite advancements, existing WiFi-based HAR research lacks consideration of subject (human) bias. This results in learning models performing well on individuals used in the training samples but failing to generalise to new/unseen subjects, in contrast to known good practices in machine learning. In this paper, we address this oversight directly by systematically examining the evaluation methodology for the WiFi-based HAR context. Specifically, we investigate the impact of Leave-One-Subject-Out Cross-Validation (LOSOCV) in a hybrid …

Investigating The Effect Of Active Living Wall On Indoor Air Quality And Energy Consumption: Case Study In Uaeu Closed Offices, Atina Ghunaim

Thesis/ Dissertation Defenses

Extreme hot climates can significantly affect indoor air quality (IAQ) and ventilation, resulting in higher energy demands. Numerous studies have demonstrated that outdoor greening, such as trees and landscaped areas, can reduce a building’s energy consumption. However, less research has been conducted on the impact of indoor vegetation on energy use and air quality. Indoor vegetation decreases carbon dioxide (CO₂) concentration by absorbing and releasing oxygen (O₂), while the evapotranspiration process further enhances (IAQ) and reduces energy expenditure. The United Arab Emirates has dry arid climate and summers with high humidity levels, causing individuals to stay longer indoors, which is …

Enhancement Of Ambient Air Quality Index Forecasting Using Optimized Ensemble Model, Vanitha M

Theses and Dissertations

Forecasting ambient air quality is essential for environmental sustainability and public health, especially in heavily populated regions such as China, India, and the United States where air pollution remains a serious concern. Traditional forecasting models often struggle to accurately represent air quality data because of its complex patterns and nonlinear interactions. To address these challenges and improve forecast performance, this research proposes a comprehensive strategy that integrates parallel heterogeneous ensemble modeling with Bayesian optimization.

The study begins with a seasonal machine learning–based imputation technique (SeasonalMLImpute) designed to handle missing data in meteorological and air quality parameters. This method is evaluated …

12.09.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Employee Profiles

In Person Account Reconciliation and Tableau Training

NSF Proposals with Consultant or Professional Services

Mems 411: Electrostatic Precipitator Design For Washu Racing Composites Team, Robert J. Wild, Takato Muro, Jackson Ford, David Wiggin

Mechanical Engineering Design Project Class

The objective of this paper is to develop an effective method to remove carbon fiber particulates from the air in the WashU Racing garage using electrostatic precipitation.

Mems 411: Talking Goniometer, Jeffrey Reinhold, Matthew Ren, Corin Riahi, Moises Rodriguez

Mechanical Engineering Design Project Class

Our project is about designing a goniometer that will aid Rachel Apter, an occupational therapy graduate student, more easily determine the angles created by limbs bending about a joint. A goniometer is essentially a protractor designed to affix its base arm to a stationary limb and it’s rotating arm to a moving limb. The moving arm follows the moving limb, measuring the coupled limb’s range of motion. The main complaint centering around goniometers is that they are hard to read due to the small tick marks that indicate the angle. To fix this problem, the goniometer will be edited to …

Mems 411: The Ball Bearing Sorter Group N, Jack Zhao, Anri Cifuentes, Shawn Xiong, Richard Li

Mechanical Engineering Design Project Class

The challenge was to design and develop an automated device capable of sorting and packaging six types of ball bearings—varying in size (1/4 inch and 1/2 inch) and material (stainless steel, brass, and nylon). The device needed to meet strict performance and design constraints, including fitting within a compact 20x20x20-inch footprint, weighing no more than 15 pounds, and sorting bearings with high speed and accuracy.

This problem represents a practical scenario in automated manufacturing, where efficient and precise sorting is crucial for streamlining assembly line operations. The solution required integrating innovative engineering mechanisms, such as size differentiation, material separation, and …

Mems 411: Mailbox Assistant, Peter Scholl, Benjamin Cortes, Garbiel Arcas, Colin Zeiss

Mechanical Engineering Design Project Class

Oftentimes elderly people struggle with reaching into their curbside mailbox from their car, especially if the mail is pushed all the way to the back. With the Mailbox Assistant, sore shoulders can be saved through a drawer that slides out from the mailbox. This modification can be made to any mailbox without altering the outside appearance thus keeping it within HOA standards.

Mems 411: Hydroponic Gardening System, Tiger Lu, Aj Shanahan, Jaquelin Guzman, Brandon Lacy

Mechanical Engineering Design Project Class

This report summarizes the engineering design process undertaken for the development of a hydroponic gardening system. The project began with selecting a concept, as a team, we decided to focus on designing a system tailored to community gardening needs. The report is organized into five main sections: Problem Understanding, Concept Generation, Concept Selection, Concept Embodiment, and Design Refinement. In the Problem Understanding phase, the team conducted extensive research on patents, codes and standards, user needs, design metrics, and project management. This foundational research was critical to ensure all aspects were considered before beginning the building process. User needs were identified …

Mems 411: Diving Surface Breaker, Chandler Gartner, Freddy Phillips, Maya Sumra, Olivia Slemmer

Mechanical Engineering Design Project Class

We have been recruited by the WashU diving team to design and construct a surface breaker for the Millstone Pool so the divers can have an affordable way to stay safe while practicing dives.

Mems 411: Timed Mosquito Egg Container Design Project, Paige Warren, Witt Ciesla, Ethan Sobel

Mechanical Engineering Design Project Class

The goal of this project is to design and construct a device that allows for the controlled study of mosquito egg-laying behavior in response to artificial light and temperature variations. Specifically, the device will limit access to cups of standing water, which serve as egg-laying sites, to preprogrammed times of day over a 7-day period.
The device should ensure the following:

• Control Access: The container should be open and closed at predetermined intervals, allowing mosquitoes to access the cups of standing water only during these times.
• Programmability: It should be easy for a novice to specify the opening and closing …

Mems 411: Ball Bearing Sorter, Abdissa Effa, Juliet Whitehead, Ayub Shifa

Mechanical Engineering Design Project Class

The challenge is to design and fabricate a compact device capable of autonomously sorting and transporting ball bearings of varying materials (chrome steel, brass, nylon) and sizes (¼” and ½”) into designated packaging stations. The device must operate efficiently, accurately, and within the constraints of a 20x20x20-inch enclosure, meeting industrial assembly line standards of speed and precision while minimizing human intervention. It aims to address the need for high-rate sorting systems in manufacturing environments, ensuring accurate material identification and classification for streamlined operations.

Mems 411: Asme Ball Bearing Sorter, Ryan Lively, Joseph Huster, Wil Collins

Mechanical Engineering Design Project Class

The ASME Student Design Competition focused on the design and construction of a ball bearing sorter. This ball bearing sorter must be capable of sorting 2 sizes of ball bearings, being 1/2 inch and 1/4 inch. For each size, there are 3 different bearing materials, brass, steel, and acetal plastic. The device is intended to have the bearings fed into a hopper, and then fully autonomously sort the bearings. The autonomous sorting was to transport the various bearings into 6 different packing stations, one for each size and material bearing. These packing stations must be easily removable. This design project …

Mems 411: Automated Assistive Toilet, Alex Scaff, Kenna Mcgahren, Daniel Sibley

Mechanical Engineering Design Project Class

How do we make toilets more accessible for all people - regardless of physical, mental, emotional impediments - while also ensuring simplicity and cost-effectiveness? Utilizing sensors, our toilet device is designed to automatically open and close the toilet lid upon approach, increasing ease of use and general hygiene of the user while being friendly to those who struggle with certain disabilities or impairments.

Mems 411: Adjustable Desk, Catryn Cattoor, Natalia Pilpil, Jamie Burgasser, Adam Wong

Mechanical Engineering Design Project Class

Design and create a desk for a special education classroom of kindergarteners to third graders. The desk needs slanting capabilities, wheel chair accessibility, raising/lower capabilities, distraction prevention capabilities, and light board capabilities. These capabilities need to be configurable for students with different needs. This desk also needs to be very durable, safe, and mobile. The main motivation for this project is the desire to provide the teacher and her students with a single, cost-effective product that is safe, easy to use, and meets their desired needs.

Mems 411: Group V Ball Bearing Sorter, Matthew Hernandez, Sean Huffert, Ethan Delair

Mechanical Engineering Design Project Class

After a semester of hard work, Team V is proud to unveil its finished prototype for the 2024-2025 ASME Student Design Competition. The theme of this challenge was "Assembly Line Sorting and Packaging." The goal of this challenge was to make a device able to satisfy the criteria of sorting between six different bearings of different sizing and material properties, and meeting spatial and time limitations. This device needed to be fast, accurate, compact, and able to sort in bulk. Team V feels like we have met most of these requirements with our final design prototype. For this project, a …

Mems 411: Rc Plane Mount For Cfd Validation, Jake Schwartz, Margot Jay, Ian Torres, Sam Ehrman

Mechanical Engineering Design Project Class

Washington University in St. Louis’ Design/Build/Fly team (WashU DBF) participates in an annual international competition with over 100 teams where they create a Remote Control (RC) plane that can perform various missions. One of the difficulties in developing a plane each year is testing the forces on the plane. Currently, Ansys and XFLR5 are used to create computational fluid dynamics (CFD) models for the plane. CFD modeling simulates air flow over the plane’s wings to analyze how to optimize the aircraft’s aerodynamics. While this is a useful strategy to predict the plane’s theoretical performance, WashU DBF Technical President, Eleni Kambouris, …

Mems 411: Mini Syringe Pump, Rachel Foulk, Braxton Hart, Camilo Hernandez

Mechanical Engineering Design Project Class

In many research and medical settings, small amounts of liquids are dispensed using syringes. Very often, syringe pumps like those shown in the left image, are used to control the amount (i.e., flow rate) of dispensed/collected fluid. There are single- or multi-style syringe pumps; the one shown is single-style; multi-style have 2-8 parallel syringes that are all pushed/pulled at the same flow rate. However, these syringe
pumps are bulky and heavy, making them impractical for many experimental setups. Commercial alternatives include very expensive syringe pumps with remote dispensers. Furthermore, it is often necessary to have two syringe pumps operate in …

Nature-Derived Flame Retardant For Cotton Fabrics With Green Coconut Shells, Tarikul Islam, Abdullah Al Rakib Shikder, Md Shahabul Hossen, Md Mazbah Uddin, Md Tanvir Hossain, M. Mahbubul Bashar

Michigan Tech Publications

This study presents an eco-friendly flame-retardant solution for cellulosic fabrics using green coconut shell (GCS) extract and phytic acid (PA). Cellulosic materials are highly flammable and release harmful gases during combustion. Conventional flame retardants may pose environmental and health risks while impacting the fabric quality. GCS extract is a rich source of tannins, phosphorus, silicates, metallic salts, and oxides and is explored as a novel flame retardant (FR) for cotton fabrics. Cotton samples were pretreated with PA and then with varying concentrations of GCS extract using a padding technique. Comprehensive characterization followed, including limiting oxygen index (LOI), thermogravimetric analysis (TGA), …

Comparing Recovery Volumes Of Steady And Unsteady Injections Into An Aquifer Storage And Recovery Well, Saeid Masoudiashtiani, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Aquifer Storage and Recovery (ASR) can involve injecting available surface water into an unconfined aquifer and then extracting it to provide secondary water for irrigation. This study demonstrates a method for evaluating the appropriateness of steady injection versus unsteady injection for an assumed situation. In design, it can be important to affect the transient: the proportion of the injected water that would be subsequently extracted (versus that remaining in the aquifer) and the proportion within the extracted water that would be an injectate (versus ambient groundwater). These proportions can be predicted from the predicted value of an ASR well's Recovery …