Engineering Commons^™

Mems 411: Improved Greens Harvester, Matthew Celentano, Nicholas Watts, Sam Friedrich, Ava Mennin

Mechanical Engineering Design Project Class

Earth Dance Organic Farm School has asked that we design an improved version of their “Quick-Cut” greens harvester. The redesign should be capable of cutting a 36 inch wide bed of greens, should roll on wheels, and should be able to operate for long periods without interruption. This report details the concept generation and selection phases of the project, wherein we elect to design the system with an aluminum extrusion frame, four- wheeled custom band saw system, and rope sweepers, among other key features. In the concept embodiment phase, we explore the features of our initial prototype and areas for …

Shared Or Dedicated Infrastructures: On The Impact Of Reprovisioning Ability, Roch A. Guérin, Kartik Hosanagar, Xinxin Li, Soumya Sen

Computer Science and Engineering Faculty Research

New technologies, such as virtualization, are transforming the way in which software and services are deployed and delivered to their users. They are behind the emergence of IT offerings such as cloud computing and converged networks, and manifest themselves through two important trends: (1) lower the cost of sharing a common infrastructure across multiple services with disparate resource requirements, and (2) dynamic provi- sioning of capacity in response to demand. Conventional wisdom is that both of these capabilities are synergistic, with greater provisioning flexibility improving the benefits derived from sharing computing or network resources. Consequently, a service operator should now …

Pipelined Parallelism In A Work-Stealing Scheduler, Thomas Kelly

All Computer Science and Engineering Research

A pipeline is a particular type of parallel program structure, often used to represent loops with cross-iteration dependencies. Pipelines cannot be expressed with the typical parallel language constructs offered by most environments. Therefore, in order to run pipelines, it is necessary to write a parallel language and scheduler with specialized support for them. Some such schedulers are written exclusively for pipelines and unable to run any other type of program, which allows for certain optimizations that take advantage of the pipeline structure. Other schedulers implement support for pipelines on top of a general-purpose scheduling algorithm. One example of such an …

Joint Reconstruction For Single-Shot Edge Illumination Phase-Contrast Tomography (Eixpct), Yujia Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

Edge illumination X-ray phase-contrast tomography (EIXPCT) is an emerging X-ray phasecontrast tomography technique for estimating the complex-valued X-ray refractive index distribution of an object with laboratory-based X-ray sources. Conventional image reconstruction approaches for EIXPCT require multiple images to be acquired at each tomographic view angle. This contributes to prolonged data-acquisition times and elevated radiation doses, which can hinder in vivo applications. In this dissertation, a new “single-shot” method without restrictive assumptions related to the object, imaging geometry or hardware is proposed for joint reconstruction (JR) of the real and imaginary-valued components of the refractive index distribution from a tomographic data …

Multi-Dimensional Extension Of The Alternating Minimization Algorithm In X-Ray Computed Tomography, Jingwei Lu

McKelvey School of Engineering Graduate Student Theses & Dissertations

X-ray computed tomography (CT) is an important and effective tool in medical and industrial

imaging applications. The state-of-the-art methods to reconstruct CT images have had

great development but also face challenges. This dissertation derives novel algorithms to

reduce bias and metal artifacts in a wide variety of imaging modalities and increase performance

in low-dose scenarios.

The most widely available CT systems still use the single-energy CT (SECT), which is

good at showing the anatomic structure of the patient body. However, in SECT image

reconstruction, energy-related information is lost. In applications like radiation treatment

planning and dose prediction, accurate energy-related information …

Systemic Risk In Financial Networks, Tathagata Banerjee

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this dissertation, I have used the network model based approach to study systemic risk in financial networks. In particular, I have worked on generalized extensions of the Eisenberg--Noe [2001] framework to account for realistic financial situations viz. pricing of corporate debt while accounting for network effects, asset liquidation mechanisms during fire sales, dynamic clearing and impact of contingent payments such as insurance and credit default swaps. First, I present formulas for the valuation of debt and equity of firms in a financial network under comonotonic endowments. I demonstrate that the comonotonic setting provides a lower bound to the price …

Development And Application Of New Methods For Magnetic Resonance Elastography Of The Brain, Charlotte Anne Guertler

McKelvey School of Engineering Graduate Student Theses & Dissertations

Accurate mechanical properties of the intact, living brain are essential for modeling traumatic brain injury (TBI). However, the properties of brain tissue in vivo have traditionally been measured in ex vivo samples. Magnetic resonance elastography (MRE) can be used to measure motion and estimate material properties of soft tissues in vivo, but MRE typically assumes tissue isotropy and homogeneity. The objective of this thesis is to improve MRE of soft tissue, like the brain, by developing and evaluating methods for in vivo estimation of heterogeneous, anisotropic properties. This was achieved through pursuit of the following aims: (1) quantifying the differences …

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge …

Role Of Submicrometer Particles In Advanced Technologies Of Carbon Capture, Zhichao Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Oxy-combustion and post-combustion carbon capture technologies are two of the most promising strategies for carbon capture and storage (CCS), which is a commonly accepted approach to address the challenge of climate change. Pressurized oxy-combustion has been actively studied due to its great potential to enhance the power plant energy efficiency by recovering latent heat from water vapor condensation without incurring additional gas compression cost. On the other hand, amine-based CO2 scrubbers have been demonstrated to have high removal efficiency of CO2 with the possibility to recycle amine solutions, which makes the technology a promising candidate for post-combustion carbon capture. Nonetheless, …

A Modular Approach For Modeling, Detecting, And Tracking Freezing Of Gait In Parkinson Disease Using Inertial Sensors, Prateek Gundannavar Vijay

McKelvey School of Engineering Graduate Student Theses & Dissertations

Parkinson disease, the second most common neurodegenerative disorder, is caused by the loss of dopaminergic subcortical neurons. Approximately 50% of people with Parkinson disease experience freezing of gait (FOG), a brief, episodic absence or marked reduction of forward progression of the feet despite the intention to walk. FOG causes falls and is resistant to medication in more than 50% of cases. FOG episodes can often be interrupted by mechanical interventions (e.g., a verbal reminder to march), but it is often not practical to apply these interventions on demand (e.g., there is not usually another person to detect an FOG episode …

Role Of Submicrometer Particles In Advanced Technologies Of Carbon Capture, Zhichao Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Oxy-combustion and post-combustion carbon capture technologies are two of the most promising strategies for carbon capture and storage (CCS), which is a commonly accepted approach to address the challenge of climate change. Pressurized oxy-combustion has been actively studied due to its great potential to enhance the power plant energy efficiency by recovering latent heat from water vapor condensation without incurring additional gas compression cost. On the other hand, amine-based CO2 scrubbers have been demonstrated to have high removal efficiency of CO2 with the possibility to recycle amine solutions, which makes the technology a promising candidate for post-combustion carbon capture. Nonetheless, …

Multi-Dimensional Extension Of The Alternating Minimization Algorithm In X-Ray Computed Tomography, Jingwei Lu

McKelvey School of Engineering Graduate Student Theses & Dissertations

X-ray computed tomography (CT) is an important and effective tool in medical and industrial imaging applications. The state-of-the-art methods to reconstruct CT images have had great development but also face challenges. This dissertation derives novel algorithms to reduce bias and metal artifacts in a wide variety of imaging modalities and increase performance in low-dose scenarios. The most widely available CT systems still use the single-energy CT (SECT), which is good at showing the anatomic structure of the patient body. However, in SECT image reconstruction, energy-related information is lost. In applications like radiation treatment planning and dose prediction, accurate energy-related information …

Mechanosensitive Epithelial Cell Scattering And Migration On Layered Matrices, Christopher Michael Walter

McKelvey School of Engineering Graduate Student Theses & Dissertations

Epithelial cells form multi-layered tissue scaffolding that makes up every organ in the body. Along with epithelial cells, the basement membrane (BM) and connective tissue are composed of various proteins that sculpt the organs and protect them from foreign macromolecules. Epithelial cells respond to various cues, both chemical and mechanical, from their surrounding matrices to aid in maintenance and repair of these layers through degradation and deposition of extracellular matrix (ECM) proteins. In cancer progression, epithelial cells lose their normal function of supporting tissue structure and instead adopt more aggressive behaviors through an epithelial-to-mesenchymal transition (EMT) of their cellular traits. …

Decoupling Information And Connectivity Via Information-Centric Transport, Hila Ben Abraham

McKelvey School of Engineering Graduate Student Theses & Dissertations

The power of Information-Centric Networking architectures (ICNs) lies in their abstraction for communication --- the request for named data. This abstraction was popularized by the HyperText Transfer Protocol (HTTP) as an application-layer abstraction, and was extended by ICNs to also serve as their network-layer abstraction. In recent years, network mechanisms for ICNs, such as scalable name-based forwarding, named-data routing and in-network caching, have been widely explored and researched. However, to the best of our knowledge, the impact of this network abstraction on ICN applications has not been explored or well understood. The motivation of this dissertation is to address this …

Alternative Approach To Sand Bags For Flood Prevention Through The Use Of 3d Printed Flood Panels, Thomas Beaver, William Mcbryan, Matthew Gilliam

Washington University / UMSL Mechanical Engineering Design Project JME 4110

This is an alternative approach to sand bags which could save time and money when implementing temporary barriers around critical areas during times of flooding in flood plains or areas near rivers.

Reducing Soil Compaction In Agriculture, Chris Gum, Justin Manzella, Brett Kayman

Washington University / UMSL Mechanical Engineering Design Project JME 4110

Our project was to prototype a device to reduce compaction in soil during industrial agricultural processes. We chose to highlight tilling as the process to focus on, but our final design could be adapted to work for many different applications.

Polarization Division Multiplexing For Optical Data Communications, Darko Ivanovich

McKelvey School of Engineering Graduate Student Theses & Dissertations

Multiple parallel channels are ubiquitous in optical communications, with spatial division multiplexing (separate physical paths) and wavelength division multiplexing (separate optical wavelengths) being the most common forms. In this research work, we investigate the viability of polarization division multiplexing, the separation of distinct parallel optical communication channels through the polarization properties of light. We investigate polarization division multiplexing based optical communication systems in five distinct parts. In the first part of the work, we define a simulation model of two or more linearly polarized optical signals (at different polarization angles) that are transmitted through a common medium (e.g., air), filtered …

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency.

Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA …

On The Fabrication And Development Of Tissue On A Chip Devices With Included Perfused Vasculatures, Usama Ismail

McKelvey School of Engineering Graduate Student Theses & Dissertations

The advent of Tissue-on-a-Chip (TiOC) devices has provided a novel way for researchers to approach biological study and drug development. As a platform that enables human in vivo conditions to be accurately replicated ex vivo, TiOC can accelerate both fundamental biological research to answer basic questions regarding tissue behavior and function (e.g., cell-cell interactions in the tumor microenvironment (TME)) and translational research that includes testing of standard and novel therapeutics. The reported work focuses on development of processes and technologies common to two classes of TiOC. The first device is a single-layer, multi-compartment microfluidic device for investigation of pancreatic …

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge …

One Knee Stair Negotiator, Naomi Marciante, Seth Trevino

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The design-to-prototype process for a One Knee Stair Negotiator, designed to reduce or eliminate the weight on one leg while climbing stairs. The decision-making processes, fabrication plan, engineering analysis, safety concerns, and risk assessments are documented. Pertinent photographs, drawings, and video links are included for clarification.

Jme 4110 Mechanical Engineering Design Project:Stir It Up, Josephn Biermann, Brittany Gray, Nathan Hopper

Washington University / UMSL Mechanical Engineering Design Project JME 4110

We are designing and building a working prototype that will be able to mix a separated beverage back to a fully integrated state. This will allow for mixing in a beverage that was separated and would possibly just be thrown away because it doesn’t taste right anymore. This will save food waste from separated beverages being thrown away as well as be environmentally friendly since it would reduce the use of single use cups and straws.

Automated Single Stream Recycling Sorting Bin (Assrsb), Daniel Pogue, Robert O'Neill, Javi Perez

Washington University / UMSL Mechanical Engineering Design Project JME 4110

As you probably know, there are many different sorting systems used by various manufacturers. It would be desirable to have a similar sorting system that uses multiple technologies to sort items, but that could easily be interchangeable with various items. Currently, recycling efforts are often costly, as humans need to sort single-stream recycling. It would be beneficial to have a system that sorts various plastic, paper, cardboard, glass, etc.

Portable Car Lift, Ramiz Ahmed, Emel Saeidghafelpoor, Nick Pusateri

Washington University / UMSL Mechanical Engineering Design Project JME 4110

No abstract provided.

Optimus Pipefitter, Jeffrey Strecker, Vito Fiordimondo, Ben Prinster

Washington University / UMSL Mechanical Engineering Design Project JME 4110

As climate change becomes a larger threat, the idea of space travel becomes a less abstract idea. If we, as a species, get to a point where settling on a new planet becomes a necessity it would be worthwhile for as much infrastructure to be built before our arrival as possible. The problem this project solves is the ability to autonomously assemble piping for plumbing and drainage. To most people, piping is not what comes to mind when thinking about modern living. Although it is certainly essential.

The Body Dryer Project, Laura Bailey, Luke Maichel, Nick Zuelke

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The information contained in this report pertains to the engineering practices to develop a working prototype of a body dryer. A body dryer that is described in the context of this report, is defined as a static structure with two air streams. The main function of the body dryer project is to investigate a replacement for a towel when one is finished showering or after swimming. This report will contain future improvements that were investigated but were not able to implement in the working prototype due to the boundaries of the system. A special shout out to Indoor Comfort Team, …

Erratum: "Imaging The Three‐Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri‐Spot Point Spread Function", Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

In the original paper, a calibration error exists in the image-formation model used to analyze experimental images taken by our microscope, causing a bias in the orientation measurements in Figs. 2 and 3. The updated measurements are shown in Fig. E1. We have also updated the supplementary material for the original article to discuss the revised PSF model and estimation algorithms (supplementary material 2) and show the revised model and measurements (Figs. S1, S3, S7, S8, and S10–S13).

Computational Fluid Dynamics Analysis Of Inverted, Multi-Element Airfoils In Ground Effect, Michael Grabis, Ramesh K. Agarwal

McKelvey School of Engineering Graduate Student Theses & Dissertations

Formula SAE cars are formula-styled race cars designed to race on an autocross circuit. The autocross circuit is mostly comprised of turning sections as well as a limited amount of straight sections for passing other cars. Highly competitive cars in the competition implement aerodynamic devices to generate negative lift for the race car. This negative lift, or downforce, increases the amount of traction between the race car’s tires and the ground ultimately allowing the drivers to turn at faster speeds. Commonly used aerodynamic devices are a front and rear wing; the wing cross sections are defined by configurations of multiple …

Computation Of Flow Fields Due To Single- And Twin-Jet Impingement, Xiang Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The thesis consists of two parts. The first part focuses on numerical simulations and their comparison with experimental data for single-jet impingement on ground. Angles between the axisymmetric jet and impingement surface considered are 15, 30 and 90 degree. It is shown that both the k-epsilon and Wray-Agarwal (WA) model can predict the flow fields in good agreement with the experimental results. The second part extends the first part to twin-jet normal impingement on the ground. It focuses on numerical simulation of fountains formed by the twin-jet impingement. The fountains can be normal straight upward when the two jets are …

Numerical Simulation Of Flow Past Naca 0012 Airfoil Using A Co-Flow Jet At Different Injection Angles To Control Lift And Drag, Da Xiao

McKelvey School of Engineering Graduate Student Theses & Dissertations

ABSTRACT OF THE THESIS

Numerical Simulation of flow Past NACA 0012 Airfoil Using a Co-Flow Jet at Different Injection Angles to Control Lift and Drag

by

Da Xiao

Master of Science in Mechanical Engineering

Washington University in St. Louis, 2019

Research Advisor: Professor Ramesh K. Agarwal

The focus of this thesis is to numerically study the aerodynamic performance of an airfoil by employing the active flow control from a co-flow jet (CFJ) near the leading edge. The study is conducted by changing the injection angle of CFJ on a location close to the leading edge on the upper surface of …