Engineering Commons^™

The Role Of Multi-Charged Responses: Construction And Application Of A Tandem Differential Mobility Analyzer (Tdma), Christopher Ray Oxford

McKelvey School of Engineering Graduate Student Theses & Dissertations

Atmospheric aerosols impact health outcomes, visibility, and the energy balance of the earth. The atmosphere contains a variety of compounds, and the volatility (phase change enthalpy and vapor pressure) of each compound determines its partitioning between the gas phase and the particle phase. The hygroscopicity (an aerosol’s affinity for water) of an atmospheric aerosol particle is determined by the many compounds present in the particle, and thus, the volatility impacts hygroscopicity. Changes in hygroscopicity alter the fraction of the aerosol deposited in the lungs and the fraction of the aerosol activated into cloud droplets. Thus, understanding the volatility and hygroscopicity …

Kernel Methods For Graph-Structured Data Analysis, Zhen Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Structured data modeled as graphs arise in many application domains, such as computer vision, bioinformatics, and sociology. In this dissertation, we focus on three important topics in graph-structured data analysis: graph comparison, graph embeddings, and graph matching, for all of which we propose effective algorithms by making use of kernel functions and the corresponding reproducing kernel Hilbert spaces.For the first topic, we develop effective graph kernels, named as "RetGK," for quantitatively measuring the similarities between graphs. Graph kernels, which are positive definite functions on graphs, are powerful similarity measures, in the sense that they make various kernel-based learning algorithms, for …

Group S- Arliss Project, Preston Bailey, Zach Stelwagon, Cal Reynolds, James Hardy

Mechanical Engineering Design Project Class

Our project was the ARLISS competition project, more specifically the second part of the project where the vehicle must survive a drop and drive to a known location over rough desert terrain. We interviewed our professor, Dr. Potter, who had previous experience with the project to understand what was required in our design. The project started with creating concept ideas and deciding on one, which initially was an airplane to avoid designing a landing mechanism and having to drive over rough terrain. However, this design proved to have too many flaws and was scrapped. The new design was a small …

Asme Design Challenge: The Jenga Stacker, Zachary Lin, Alex Chernauskas, Mitch Dorsey, Alex Remmers

Mechanical Engineering Design Project Class

The 2020 ASME Design Challenge requires teams to build a compact engineering system capable of manufacturing a tower made exclusively from standard-sized sheets of paper. The validation of the design will include testing for manufacturing speed, height of tower, and ability to support a load. Our senior design project focuses on the stacking mechanism and is designed to stack a 4 in x 4 in tower out of prepared 4 in x 1.5 in x 1.75 in paper boxes from the ground up.

Anion Exchange And Bipolar Membranes For Electrochemical Energy Conversion And Storage, Zhongyang Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Anion exchange and bipolar membrane fuel cells generate electrical energy directly from chemical fuels and have attracted considerable interests as alternate power sources for large market applications, such as transportation (hydrogen fuel cells) and unmanned vehicles (sodium borohydride fuel cells). Anion exchange membrane (AEM), generally composed of a polymer with covalently tethered ionic groups, is the central component of the fuel cell serving as the electrolyte, conducting hydroxide ions from cathode to anode, where fast ionic conduction is directly related to power output. However, AEMs currently used in fuel cells (H2 fuel cells and sodium borohydride fuel cells) exhibit ion …

Expanding The Palette: Synthesizing Microencapsulated Organic Phase Change Materials In Metallic Matrices For Transient Thermal Applications, Melissa Kate Mccann

McKelvey School of Engineering Graduate Student Theses & Dissertations

As the demand for smaller and faster electronics increases, it becomes increasingly challenging to effectively manage the generated heat without hindering device performance in applications whose thermal profiles are dominated by pulsed thermal loads. Heat propagation in a system can be characterized by steady or transient state heat transfer. In steady state, the temperature at any particular point remains constant after thermal equilibrium is reached. In a transient state, the temperature within a system varies over time. The changing parameters and time dependency associated with a transient regime make heat transfer calculations far more complex than in a steady state. …

Ph-Sensitive Oxygen Release Microspheres To Enhance Cell Survival In Ischemic Condition, Zhongting Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Ischemic diseases such as myocardial infarction, stroke and limb ischemia are severe cardiovascular diseases with high rate of death and millions of people suffered from these diseases. Under ischemic environment, cells die due to deficient supply of nutrient and oxygen. To regenerate ischemic tissues, stem cell therapy is a promising approach because stem cells can differentiate into cells necessary for the regeneration. However, stem cell therapy has limitations. For example, few cells can survive under harsh ischemic environment. To enhance stem cells survival, implantation of oxygen release microspheres to sustained supply cells with oxygen represents an effective strategy. Previously, our …

Molecular Dynamics Studies Of Thin-Film Evaporation: The Effect Of Graphene-Coated Silicon On Water Evaporation Behavior, Rui Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

Conventional single-phase air or liquid cooling methods are insufficient to dissipate the high heat flux of next-generation electronic systems. Thin-film evaporation is one of the most promising solutions, because it takes advantage of the large amount of latent heat in the phase change process. It is important to understand the relationship between interfacial thermal resistance, surface wettability, and thin-film evaporation behavior. In this study, non-equilibrium molecular dynamics simulations are used to study mass and heat transfer in thin-film evaporation of water on a silicon substrate, and equilibrium molecular dynamics simulations are used to study the surface wettability by measuring contact …

3d Chocolate Printer Bed Design, Dean Oken, Jacob Margolin, Ben Hartmann, Sam Grossman

Mechanical Engineering Design Project Class

The client wished for a device to gain the interest of young undergraduate students into basic thermal science and fluid dynamics concepts. A 3D printer bed was created from concept to prototype design and paired with chocolate dropper teams to complete the project and accomplish the client's goals.

Mems 411 Group L (Fall 2019) - Speedy Seeder Final Report, Michael Morrow, Christopher Nelson, Ross Frame

Mechanical Engineering Design Project Class

The Speedy Seeder or ”SS” is a device designed to decrease the time it takes to fill one seed plot by hand to roughly sixteen percent of the time. The customer of the SS is EarthDance Organic Farms School. EarthDance fills a large number of plots each year by placing a seed in every single compartment which come in three sizes: 32, 72, and 128 compartments per plot. Filling a single plot by hand can take roughly 8 minutes. The SS makes filling a plot much easier and faster, allowing a single plot to be filled in under 75 seconds. …

Enhanced Heat Transfer Performance By Shape Optimization Of A Non-Axisymmetric Droplet Evaporating On A Heated Micropillar, Haotian Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Abstract

Enhanced Heat Transfer Performance by Shape Optimization of a Non-axisymmetric Droplet Evaporating on a Heated Micropillar

By

Haotian Wu

Department of Mechanical Engineering and Materials Science

Washington University in St. Louis, 2019

Research Advisor: Professor Damena Agonafer

The stacked multilayer 3D IC structure used in next generation high-powered electronics poses great challenges in dissipating their large heat flux, which causes extreme difficulties for traditional cooling technologies. In response, more advanced two-phase liquid cooling technologies, such as droplet evaporation, which utilizes the latent heat of vaporization to remove excessive heat, have been widely investigated. Compared to traditional single-phase cooling techniques, …

Violin Bow-Hand Prosthetic, Jonathan Smith, Jonathon Azziz, Shawn Pavey

Mechanical Engineering Design Project Class

The violin bow hand prosthetic was designed for a young violin player seeking to upgrade the functionality of his current violin prosthetic device. His current device is rigid, forcing him to play mostly with his shoulder. Since the strength of his wrist was unknown, we designed a prosthetic with enough brace flexibility to enable the user to control the bow motion with his own wrist. We also added an axis of rotation and spring mechanism to supplement this motion and provide him the equivalence of fine finger adjustments. The full design process of the prosthetic is documented in this report, …

Violin Bow-Hand Prosthetic, Ron Hayes Jr, Kc Cook, Romario Lobban, Muriel Drexler

Mechanical Engineering Design Project Class

The violin bow-hand prosthetic aims to mimic the natural hold and motion of a violinist’s bow-hand. The prosthetic is for a violinist who is missing the majority of their hand, but still has full range of motion in the wrist. Focusing on maintaining a natural playing style greatly influenced the design of the device to be user safe, durable, comfortable, easy to use, inexpensive, and practical. Many of these features were achieved by using 3D printed plastic and foam composites. These materials were selected based on strength and deflection analyses of 3-D simulations performed in SolidWorks and the ease of …

Group M: Arliss Canister Vehicle, Greyson Bourgeois, Eleanor Macklin, Romail Dawani, Rachel Sample

Mechanical Engineering Design Project Class

This project is a dicycle designed for the ARLISS Canister Competition. In this competition, the device is loaded into a rocket which is then launched to about 12000 ft before releasing the device. Then it must safely land and autonomously navigate to a predetermined GPS location on the ground. Due to the fact that this is a mechanical engineering design project and the time restrictions of this class, we focused on the physical aspect of the project, such as building a device that can survive the launch and landing and traverse several kilometers through the desert, forgoing the autonomous navigation …

Point Cloud Processing With Neural Networks, Stephanie Miller, Jiahao Li

All Computer Science and Engineering Research

In this project, we explore new techniques and architectures for applying deep neural networks when the input is point cloud data. We first consider applying convolutions on regular pixel and voxel grids, using polynomials of point coordinates and Fourier transforms to get a rich feature representation for all points mapped to the same pixel or voxel. We also apply these ideas to generalize the recently proposed "interpolated convolution", by learning continuous-space kernels as a combination of polynomial and Fourier basis kernels. Experiments on the ModelNet40 dataset demonstrate that our methods have superior performance over the baselines in 3D object recognition.

T-Shirt Strip Dispenser, Maxwell Dimgba, Syeda Mohsin, Sabrina Nguyen

Mechanical Engineering Design Project Class

There is a massive amount of waste around the textile industry. New garments are constantly being made and old garments are consistently finding themselves in landfills. This project aims to cut down on this waste. Mary Susan RuppertStroescu of the Sam Fox School at Washington University in St. Louis has developed a process to turn old garments into new ones in a practice known as up-cycling. By cutting old garments into half-inch strips, laying and adhering them flat on a sheet of dissolvable paper, and sewing over them in interesting patterns she is able to create extraordinary new designs. This …

Group N: Fluid Flow Testing Apparatus, Jonathan Fleming, Braden Kerr, Abel Soloman

Mechanical Engineering Design Project Class

A fluid flow testing apparatus was needed to accurately test valves relative to the conditions seen in the factory of a local St. Louis brewery. After concept generation, a rotating track that toggled the valve between open and closed was decided on by the team. Construction of an initial prototype was done over 3 weeks with a total budget of 400 USD. The initial prototype satisfied almost all of the performance goals: capable of cycling 200 times without intervention, 1 paper-towel of leakage at most, and upper reservoir level consistency within 10 percent. To improve the initial prototype, the team …

Lupd - Leisure Underwater Propulsion Device, James Abraham, Tanner Nordell, Holden Schmidt, Noah Trimark

Mechanical Engineering Design Project Class

The main objective of this Design Project was to create a hands-free, wearable underwater propulsion device. The target consumer is leisure divers, so managing cost was important. Current products on the market do not allow divers to be hands-free while diving and are very expensive. The design process began with an interview with Josh An, a Masters Degree candidate at Washington University in St. Louis. Josh is an avid diver and wanted to see if it was possible to develop a cheap underwater jet pack for leisure diving. After multiple design concepts and mock up prototypes, our team decided on …

Ice Cream Dispensing Machine, Katie Bahnck, Rachel Lockwood, Marie White, Simone Raeth

Mechanical Engineering Design Project Class

Each August, Washington University in St. Louis (WashU) welcomes hundreds of new engineering students to its McKelvey School of Engineering. Historically, during orientation activities, WashU’s Engineering Student Services (ESS) serves dessert bars to the new students, where they must line up and make their own desserts manually. To make the dessert bar more interactive and give students a primer for what their engineering studies hold, we would like to introduce an ice cream sundae making machine to the spread. A semi-automated ice cream machine would allow students to customize their ice cream sundae while observing the everyday mechanics required to …

Jet Beluga: Diver Propulsion Wearable, Jacob Graham, Bernardo Amaral Neves, Ethan Genter

Mechanical Engineering Design Project Class

Scuba diving is a physically and mentally challenging task performed in both recreational and professional settings. Recreational divers seek to experience the marine world for extended periods of time without buoyant resistance. Rescue divers, military personnel, and underwater construction workers train to execute complicated tasks in a limited time period. Diver propulsion vehicles can improve the quality of recreational diving as well as the effectiveness of diving as performed in professional settings. The following report describes the design and motivations for a wearable diver propulsion device that provides the benefits of increased speed and mobility while limiting the amount of …

Sweet Spot Demonstration, Andrew Amend, Mitchell Smith, Ian Fish, Curtis Hoffman

Mechanical Engineering Design Project Class

Our goal was to design and build an exhibit for the St. Louis Science Center to serve as a teaching tool to help explain the unintuitive concept of a baseball bat’s sweet spot to a typical children museum’s visitor, a 5th grade student, in an interesting and visually pleasing way. The sweet spot of the bat is colloquially known as the place that makes the best contact with the ball, and it is determined by a combination of the center of percussion and location of vibrational nodes. We focused on showing how the location of bat-ball impact affects the vibration …

Sweet Spot Demonstration, Keval Amin, Beau Allen, Kieran Lenssen, Ricardo Del Olmo Parrado

Mechanical Engineering Design Project Class

The purpose of this project was to create a sweet spot exhibit for the St. Louis Science Center to demonstrate the basic dynamic and vibrational theory behind the game of baseball. This demonstration focuses on the dynamics of batting and the effects that induced bat vibrations have on the energy transfer from the bat to the ball. Through this demonstration, the vibrational nodes within a baseball bat can be measured based on the ball’s contact with the ”sweet spot,” or the area on the barrel of the bat that induces the least amount of bat vibration. The project went through …

Asme 2020 Design Challenge, Anthony Acosta, Justine Alandy-Dy, Michael Lorberg, Nathan Vaska

Mechanical Engineering Design Project Class

Our project was to build a machine that would fulfill the requirements for the ASME 2020 design challenge, which was called, ”Building to the Sky.” The rules of the challenge were to build a machine that would take ordinary 8.5” x 11” sheets of paper and stack them into a tower. To accomplish this task, we decided to make our paper tower out of accordion-shaped folds that would be placed on top of each other, alternating in 90 degree orientations. Our device is divided into various sub-components, each which manipulate the paper in various ways. We first have a mechanism …

Violin Prosthetic, Justin Kransdorf, Julia Rifkin, Hayden Reynolds, Payal Hukeri

Mechanical Engineering Design Project Class

Sam, an 11-year-old violin player was born without fingers or a thumb on his right hand. In order to learn the basics of violin, he currently uses a custom made prosthetic that allows him to hold a violin bow. However, his current prosthetic does not allow for the bow angle to change relative to his wrist, and thus, he cannot perform many techniques that are important to him furthering his violin skills. Specifically, his prosthetic allows Sam to use only a small percentage of the bow. For this project, a prosthetic was designed for Sam with the goal being to …

Automated Whiteboard Eraser, Trent Houpt, Tyler Polasek, Kenny Huang, Rocky Luo

Mechanical Engineering Design Project Class

The Automated Whiteboard Eraser is a product designed to erase whiteboards with the touch of a button. With this product students and teachers will be able to save time and energy as they can continue to work without having to stop and erase. From our research others have attempted to construct similar products. We intend to improve these thoughts and designs in order to build a better and more efficient product.

Board Erasing Device, Mark Fernandez, Christopher Sheffels, Joshua Miller

Mechanical Engineering Design Project Class

The Board Erasing Device is a portable automatic device designed to streamline a university lecturer’s board writing process by automatically erasing whiteboards while they are writing notes on adjacent boards. Our goal during this project was to design, build, and test a portable, automatic, and aesthetically pleasing device compatible with most standard whiteboards on Washington University in St. Louis’ Danforth campus. To that end, with a budget of $400, we created a prototype device to accomplish just that. Our prototype includes a felt eraser, pressed into the whiteboard via magnets. The eraser piece spans all eight feet of width on …

3d Chocolate Printer Dropper, Jessica Jimenez, Jacqueline Pielli, Shuhan Zhang

Mechanical Engineering Design Project Class

The Mechanical Engineering Department at Washington University in St. Louis is working to stimulate interest in the fields of fluid dynamics and thermal sciences, as students are not typically exposed to these topics within the first two years of school. Dr. Okamoto, Jeff Krampf, and Dr. Weisensee of the Mechanical Engineering Department would like to remedy this situation by developing a laboratory experiment for first year students that utilizes a 3D chocolate printer to teach thermal-fluid concepts in a fun and engaging manner. The goal of this project is to build a chocolate droplet dispensing system, which is a part …

Diver Propulsion Wearable, Joseph Lucca Paletta, Andrew Kessler, Andrew Beukelman, Nico Topulos

Mechanical Engineering Design Project Class

This project was proposed by Jin Hwan (Josh) An, a current undergraduate student in the Olin Business School at Washington University in St Louis. Given his interest in diving and his experience with current diver propulsion vehicles, Josh has challenged us to design a hands-free diver propulsion wearable (DPW). While Josh has left the project rather open-ended for the engineers, the main challenge is to create a design that can propel the diver using a hands-free control system. Having a hands-free controller will allow the user to engage in other tasks while gliding underwater. Ideally, this design would be useful …

Modeling The Effects Of Distribution System Topology On Water Quality, Chun-Ying Chao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Inadequate treatment of drinking water causes the formation of disinfection by-products and the regrowth of harmful microbial species. Various studies have addressed the problem of water quality monitoring, but very few have employed topological analysis, a valuable mathematical tool widely applied in biological, business, and social research. This thesis examines the relationship between the topological properties of water distribution systems and water-quality models. In particular, the research proposes a novel framework for mapping network topological attributes to water-quality models. This research adopts topological metrics to assess the accuracy of the predictions of chlorine concentrations in dead ends. It examines four …

Static Taint Analysis Of Binary Executables Using Architecture-Neutral Intermediate Representation, Elaine Cole

All Computer Science and Engineering Research

Ghidra, National Security Agency’s powerful reverse engineering framework, was recently released open-source in April 2019 and is capable of lifting instructions from a wide variety of processor architectures into its own register transfer language called p-code. In this project, we present a new tool which leverages Ghidra’s specific architecture-neutral intermediate representation to construct a control flow graph modeling all program executions of a given binary and apply static taint analysis. This technique is capable of identifying the information flow of malicious input from untrusted sources that may interact with key sinks or parts of the system without needing access to …