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Full-Text Articles in Engineering

Information-Based Analysis And Control Of Recurrent Linear Networks And Recurrent Networks With Sigmoidal Nonlinearities, Deslin Menolascino Dec 2018

Information-Based Analysis And Control Of Recurrent Linear Networks And Recurrent Networks With Sigmoidal Nonlinearities, Deslin Menolascino

Engineering and Applied Science Theses & Dissertations

Linear dynamical models have served as an analytically tractable approximation for a variety of natural and engineered systems. Recently, such models have been used to describe high-level diffusive interactions in the activation of complex networks, including those in the brain. In this regard, classical tools from control theory, including controllability analysis, have been used to assay the extent to which such networks might respond to their afferent inputs. However, for natural systems such as brain networks, it is not clear whether advantageous control properties necessarily correspond to useful functionality. That is, are systems that are highly controllable (according to certain ...


Radiolabeled Nanohydroxyapatite As A Platform For The Development Of New Pet Imaging Agents, Stacy Lee Queern Dec 2018

Radiolabeled Nanohydroxyapatite As A Platform For The Development Of New Pet Imaging Agents, Stacy Lee Queern

Arts & Sciences Electronic Theses and Dissertations

Positron emission tomography (PET) imaging utilizes drugs labeled with positron emitters to target and evaluate different biological processes occurring in the body. Tailoring medicine to the individual allows for higher quality of care with better diagnosis and treatment and is a key purpose for advancing research into developing new platforms for PET imaging agents. A PET nuclide of high interest for the development of these agents is 89Zr. This can be attributed to the long half-life of 3.27 days and low positron energy of 89Zr.

In this work, we developed a production method for 89Zr using Y sputtered coins ...


Tunable Electronic And Optical Properties Of Low-Dimensional Materials, Shiyuan Gao Dec 2018

Tunable Electronic And Optical Properties Of Low-Dimensional Materials, Shiyuan Gao

Arts & Sciences Electronic Theses and Dissertations

Two-dimensional (2D) materials with single or a few atomic layers, such as graphene, hexagonal boron nitride (h-BN) and transition metal dichalcogenides (TMDCs), and the heterostructures or one-dimensional (1D) nanostructures they form, have attracted much attention recently as unique platforms for studying many condensed-matter phenomena and holds great potentials for nanoelectronics and optoelectronic applications. Apart from their unique intrinsic properties which has been intensively studied for over a decade by now, they also allow external control of many degrees of freedom, such as electrical gating, doping and layer stacking. In this thesis, I present a theoretical study of the electronic and ...


Anisotropic Tissue Maker, Jake Ireland, Jaryd Huffman, Sarah Mohrmann, Daniel Cano Oct 2018

Anisotropic Tissue Maker, Jake Ireland, Jaryd Huffman, Sarah Mohrmann, Daniel Cano

Mechanical Engineering Design Project Class

Traumatic brain injury (TBI) is a common injury that is not thoroughly understood. Data on brain mechanics and motion are not abundant during the time of impact. In order to accumulate more data and achieve a better understanding of how the injury occurs tissue mimics can be made.


Residential Automatic Door Opener, Steven Downs, Ardian Pollo, Ethan Bredemeier Oct 2018

Residential Automatic Door Opener, Steven Downs, Ardian Pollo, Ethan Bredemeier

Mechanical Engineering Design Project Class

This project proposes an innovative design for an automatic door opener intended for external doors of residential homes. The intended customers are elderly and disabled people who may benefit from such a device while entering and exiting their homes. The goal is to create an affordable product to compete with existing products that are relatively expensive to make such devices more accessible.


Group T Asme Design Challenge Project, Thomas Orgielewicz, Hayden Von Hoffmann, Michael Chirumbole Oct 2018

Group T Asme Design Challenge Project, Thomas Orgielewicz, Hayden Von Hoffmann, Michael Chirumbole

Mechanical Engineering Design Project Class

Design and build a RC Robot eligible to compete in the 2019 ASME Challenge, the "Pick-and-Place Race"


Tendon Rehabilitator, David Ricks, Lucas Parisot, Benjamin Wang Oct 2018

Tendon Rehabilitator, David Ricks, Lucas Parisot, Benjamin Wang

Mechanical Engineering Design Project Class

Our goal was to provide a cheap, portable and easy way for those suffering from medial epicondylitis tendinosis, or golfers elbow, to perform rehabbing exercises.


Asme Design Competition - Group H, Melanie Self, Ben Tattersfield, Joshua Emde Oct 2018

Asme Design Competition - Group H, Melanie Self, Ben Tattersfield, Joshua Emde

Mechanical Engineering Design Project Class

This document presents our solution for the ASME pick-and-place design competition. In brief, the challenge is to collect balls from an arena and return them to a ‘home base’. The specifics of the competition are elaborated on within. The document walks through the design decisions that went into the prototype; the Goalkeeper concept that we ultimately landed on best solved the problems presented by the challenge statement as interpreted by our customer, Dr. James Jackson Potter. Several of the design choices were made by applying mathematical relationships, with the math and results included to illuminate our methods. We include a ...


Pick And Place Bot: Asme Design Challenge, Steven Mumford, Josh Clark, Stephan Meyer Oct 2018

Pick And Place Bot: Asme Design Challenge, Steven Mumford, Josh Clark, Stephan Meyer

Mechanical Engineering Design Project Class

Design a bot that meets the standards of and is able to compete in the 2019 ASME Design Challenge.


Lacrosse Ball Passing Machine, William Galik, Daniel Finer, Matt Jenkins Oct 2018

Lacrosse Ball Passing Machine, William Galik, Daniel Finer, Matt Jenkins

Mechanical Engineering Design Project Class

Design and build a lacrosse ball passing machine that utilizes an automated ball sorting mechanism to shoot balls up to 60 mph with 80 percent accuracy at a 1 square yard target.


Universal Tube Fixture, Griffin Kivitz, Matthew Whitehill, Jason Hsu Oct 2018

Universal Tube Fixture, Griffin Kivitz, Matthew Whitehill, Jason Hsu

Mechanical Engineering Design Project Class

The goal of this design project was to create a device that can aid in the assembly of glue joints between concentric tubes. In many medical devices, whether they be laser probes, retractable injectors, or other devices with actuating parts, there are often concentric glue joints. The problem we are trying to solve is controlling where the 2 tubes are relative to one another when they are glued.


T-Shirt Square Cutter, Austin Chawgo, Kendall Weishaar, Samir Lopez Oct 2018

T-Shirt Square Cutter, Austin Chawgo, Kendall Weishaar, Samir Lopez

Mechanical Engineering Design Project Class

Each year, Americans waste millions of pounds of textiles in the form of clothing that is thrown away. Professor Mary Ruppert-Stroescu from the Sam Fox School of Design seeks to combat this by reusing the old fabric from discarded clothes and creating new, fashionable clothing. To do this, her and her students cut up donated shirts into small squares, by hand, using scissors and fabric cutters and sew them together using a method developed by her.. This process is very time consuming and limits the commercial viability of this process. The T-shirt Cutter design, detailed below, has the potential to ...


Group B: Polar Coordinate Whiteboard Writer, Dylan Wu, Zexin Han, Keon Kim, Jiahao Wei Oct 2018

Group B: Polar Coordinate Whiteboard Writer, Dylan Wu, Zexin Han, Keon Kim, Jiahao Wei

Mechanical Engineering Design Project Class

From the initial funding of $250.00, our group attempted to make a polar coordinate whiteboard writer that was to be used in educational settings. Market for polar coordinate whiteboard writer is a blue ocean. Having a successful prototype will allow us to find a niche place in a market that shares border with the global education market.


Group O - Lacrosse Ball Passer, Mackenzie Gordon, Jake Mennemeier, Conor Pellas Oct 2018

Group O - Lacrosse Ball Passer, Mackenzie Gordon, Jake Mennemeier, Conor Pellas

Mechanical Engineering Design Project Class

The goal of our design group was to make a lacrosse ball passer that could be used in a team practice or individual setting. Wayne Jaekle, WashU’s head lacrosse coach defined major customer needs as producing a consistent pass speed and angle, an interactive interface allowing an automatic time interval between passes, and being easy to load. These needs lead to our main design goals: 1. A ball capacity of 30, 2. A minimum pass speed of 30 mph, and 3. A 5 second time interval between passes. Mock ups and brainstorming exercises led to our team’s selection ...


Group V: Color Mixer, Kate Baskin, Mark Livshin, Andy Johnston Oct 2018

Group V: Color Mixer, Kate Baskin, Mark Livshin, Andy Johnston

Mechanical Engineering Design Project Class

This project was an exercise in product design, modeling, and prototyping. The result of this process was a partially functional prototype which successfully met two of the three design goals.


Group L: T-Shirt2 Cutter, Sophie Anderson, Avery German, Taylor Tuleja Oct 2018

Group L: T-Shirt2 Cutter, Sophie Anderson, Avery German, Taylor Tuleja

Mechanical Engineering Design Project Class

The T-shirt square cutter was commissioned by fashion design professor at Washington University, Dr. Mary RuppertStroescu who has developed a method of turning T-shirts that might have otherwise been thrown away into a unique, woven fabric. Dr. Ruppert-Stroescu cuts T-shirts into either strips or squares that she then quilts together, she uses this fabric to make one-of-a-kind clothes, bags, and rugs. Though she is proficient at weaving the fabric scraps together, cutting the Tshirts was a very time-consuming process – it takes her at least 20 minutes to cut a T-shirt into squares by hand. Our team was tasked with designing ...


Arliss Competition Canister Vehicle, Jessie Goldberg, Nicholas Cornejo, Tyler Smith, Rachel Kershner Oct 2018

Arliss Competition Canister Vehicle, Jessie Goldberg, Nicholas Cornejo, Tyler Smith, Rachel Kershner

Mechanical Engineering Design Project Class

For our project, we designed a canister vehicle that fits the design specifications of the ARLISS competition. For the ARLISS competition, the vehicles are loaded into a rocket, launched approximately 10,000 feet into the air, released, and then must autonomously navigate to a predetermined target on the ground. Because of our time restraint, we are focused on designing a vehicle of the correct dimensions (a maximum mass of 1050g, a maximum diameter of 146mm, and a maximum height of 240mm) that can simply travel on the ground over multiple types of terrain. Additionally, we designed a parachute release mechanism ...


Decoupling Information And Connectivity Via Information-Centric Transport, Hila Ben Abraham, Jyoti Parwatikar, John Dehart, Adam Drescher, Patrick Crowley Aug 2018

Decoupling Information And Connectivity Via Information-Centric Transport, Hila Ben Abraham, Jyoti Parwatikar, John Dehart, Adam Drescher, Patrick Crowley

Computer Science and Engineering Publications and Presentations

The power of Information-Centric Networking (ICN) architectures lies in their abstraction for communication --- the request for named data. This abstraction promises that applications can choose to operate only in the information plane, agnostic to the mechanisms implemented in the connectivity plane. However, despite this powerful promise, the information and connectivity planes are presently coupled in today's incarnations of leading ICNs by a core architectural component, the forwarding strategy. Presently, this component is not sustainable: it implements both the information and connectivity mechanisms without specifying who should choose a forwarding strategy --- an application developer or the network operator. In practice ...


In Vivo Vascular Imaging With Photoacoustic Microscopy, Hsun-Chia Hsu Aug 2018

In Vivo Vascular Imaging With Photoacoustic Microscopy, Hsun-Chia Hsu

Engineering and Applied Science Theses & Dissertations

Photoacoustic (PA) tomography (PAT) has received extensive attention in the last decade for its capability to provide label-free structural and functional imaging in biological tissue with highly scalable spatial resolution and penetration depth. Compared to modern optical modalities, PAT offers speckle-free images and is more sensitive to optical absorption contrast (with 100% relative sensitivity). By implementing different regimes of optical wavelength, PAT can be used to image diverse light-absorbing biomolecules. For example, hemoglobin is of particular interest in the visible wavelength regime owing to its dominant absorption, and lipids and water are more commonly studied in the near-infrared regime.

In ...


Developing Multi-Scale Models For Water Quality Management In Drinking Water Distribution Systems, Ahmed A. Abokifa Aug 2018

Developing Multi-Scale Models For Water Quality Management In Drinking Water Distribution Systems, Ahmed A. Abokifa

Engineering and Applied Science Theses & Dissertations

Drinking water supply systems belong to the group of critical infrastructure systems that support the socioeconomic development of our modern societies. In addition, drinking water infrastructure plays a key role in the protection of public health by providing a common access to clean and safe water for all our municipal, industrial, and firefighting purposes. Yet, in the United States, much of our national water infrastructure is now approaching the end of its useful life while investments in its replacement and rehabilitation have been consistently inadequate. Furthermore, the aging water infrastructure has often been operated empirically, and the embracement of modern ...


Development And Application Of Hybrid Wray-Agarwal Turbulence Model And Large-Eddy Simulation, Xu Han Aug 2018

Development And Application Of Hybrid Wray-Agarwal Turbulence Model And Large-Eddy Simulation, Xu Han

Engineering and Applied Science Theses & Dissertations

Rapid development in computing power in past five decades along with the development and progress in building blocks of Computational Fluid Dynamics (CFD) technology has made CFD an indispensable tool for modern engineering analysis and design of fluid-based products and systems. For CFD analysis, Reynolds-Averaged Navier-Stokes (RANS) equations are currently the most widely used fluid equations in the industry. RANS methods require modeling of turbulence effect (i.e. turbulence modeling) based on empirical relations and therefore often produce low accuracy results for many flows. In recent years, the Large Eddy Simulation (LES) approach has been developed which has shown promise ...


Lignin Conversion To Value-Added Products Via Heterogeneous Catalysts, Yu Gao Aug 2018

Lignin Conversion To Value-Added Products Via Heterogeneous Catalysts, Yu Gao

Engineering and Applied Science Theses & Dissertations

Increasing world population has led to great demands for fuels, chemicals, and materials, and has raised concerns over the depletion of non-renewable resources and the environmental impacts of their processing and utilization. However, the biorefinery concept suggests lignocellulosic biomass can be used as an alternative resource for producing a range of fuels, chemicals and materials to fulfill these demands in a sustainable way. Hence, fermentation technologies are widely developed to efficiently utilize lignocellulosic carbohydrates. However, the non-carbohydrate fraction of biomass, lignin, is still considered as waste and is under-utilized as low-grade fuel, mainly for local heat and electricity production. Since ...


Multi-Gpu Acceleration Of Iterative X-Ray Ct Image Reconstruction, Ayan Mitra Aug 2018

Multi-Gpu Acceleration Of Iterative X-Ray Ct Image Reconstruction, Ayan Mitra

Engineering and Applied Science Theses & Dissertations

X-ray computed tomography is a widely used medical imaging modality for screening and diagnosing diseases and for image-guided radiation therapy treatment planning. Statistical iterative reconstruction (SIR) algorithms have the potential to significantly reduce image artifacts by minimizing a cost function that models the physics and statistics of the data acquisition process in X-ray CT. SIR algorithms have superior performance compared to traditional analytical reconstructions for a wide range of applications including nonstandard geometries arising from irregular sampling, limited angular range, missing data, and low-dose CT. The main hurdle for the widespread adoption of SIR algorithms in multislice X-ray CT reconstruction ...


Development And Application Of Rotation And Curvature Correction To Wray-Agarwal Turbulence Model, Xiao Zhang Aug 2018

Development And Application Of Rotation And Curvature Correction To Wray-Agarwal Turbulence Model, Xiao Zhang

Engineering and Applied Science Theses & Dissertations

Computational Fluid Dynamics (CFD) is increasingly playing a significant role in the analysis and design of aircrafts, turbomachines, automobiles, and in many other industrial applications. In majority of the applications, the fluid flow is generally turbulent. The accurate prediction of turbulent flows to date remains a challenging problem in CFD. In almost all industrial applications, Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a turbulence model are employed for simulation and prediction of turbulent flows. Currently the one-equation (namely the Spalart-Allmaras (SA) and Wray-Agarwal (WA) and two-equation (namely the k-ε and Shear Stress Transport k-ω) turbulence models remain the most widely ...


Forward Electrophysiological Modeling And Inverse Problem For Uterine Contractions During Pregnancy, Mengxue Zhang Aug 2018

Forward Electrophysiological Modeling And Inverse Problem For Uterine Contractions During Pregnancy, Mengxue Zhang

Engineering and Applied Science Theses & Dissertations

Uterine contractile dysfunction during pregnancy is a significant healthcare challenge that imposes heavy medical and financial burdens on both human beings and society. In the U.S., about 12% of babies are born prematurely each year, which is a leading cause of neonatal mortality and increases the possibility of having subsequent health problems. Post-term birth, in which a baby is born after 42 weeks of gestation, can cause risks for both the newborn and the mother. Currently, there is a limited understanding of how the uterus transitions from quiescence to excitation, which hampers our ability to detect labor and treat ...


Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler Aug 2018

Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler

Engineering and Applied Science Theses & Dissertations

The brain connects to, modulates, and receives information from every organ in the body. As such, brain-computer interfaces (BCIs) have vast potential for diagnostics, medical therapies, and even augmentation or enhancement of normal functions. BCIs provide a means to explore the furthest corners of what it means to think, to feel, and to act—to experience the world and to be who you are. This work focuses on the development of a chronic bi-directional BCI for sensorimotor restoration through the use of separable frequency bands for recording motor intent and providing sensory feedback via electrocortical stimulation. Epidural cortical surface electrodes ...


Engineering Robust And Programmable Biological Systems, Tatenda Shopera Aug 2018

Engineering Robust And Programmable Biological Systems, Tatenda Shopera

Engineering and Applied Science Theses & Dissertations

The ability to engineer programmable biological systems using complex artificial gene networks has great potential to unlock important innovative solutions to many biotechnological challenges. While cells have been engineered to implement complex information processing algorithms and to produce food, materials, and pharmaceuticals, many innovative applications are yet to be realized due to our poor understanding of how robust, reliable, and predictable artificial gene circuits are built. In this work, we demonstrate that robust complex cellular behaviors (e.g., bistability and gene expression dynamics) can be achieved by engineering gene regulatory architecture and increasing the complexity of genetic networks. We further ...


Spin Alignment Generated In Inelastic Nuclear Reactions, Daniel Hoff Aug 2018

Spin Alignment Generated In Inelastic Nuclear Reactions, Daniel Hoff

Arts & Sciences Electronic Theses and Dissertations

The spin alignment of inelastically excited 7Li projectiles, when the target remains in its ground state, was determined through angular-correlation measurements between the breakup fragments of 7Li_ (_ + t). It was found that 7Li_ is largely aligned along the beam axis (longitudinal) in this type of inelastic reaction, regardless of the target. This longitudinal alignment is well described by DWBA calculations, which can be explained by an angular-momentum-excitation-energy mismatch condition. These calculations also explain the longitudinal spin alignment of excited nuclei in several other systems, showing the phenomenon is more general. The experiment involving 7Li was performed at the Texas ...


Self-Powered Time-Keeping And Time-Of-Occurrence Sensing, Liang Zhou Aug 2018

Self-Powered Time-Keeping And Time-Of-Occurrence Sensing, Liang Zhou

Engineering and Applied Science Theses & Dissertations

Self-powered and passive Internet-of-Things (IoT) devices (e.g. RFID tags, financial assets, wireless sensors and surface-mount devices) have been widely deployed in our everyday and industrial applications. While diverse functionalities have been implemented in passive systems, the lack of a reference clock limits the design space of such devices used for applications such as time-stamping sensing, recording and dynamic authentication. Self-powered time-keeping in passive systems has been challenging because they do not have access to continuous power sources. While energy transducers can harvest power from ambient environment, the intermittent power cannot support continuous operation for reference clocks. The thesis of ...


Development And Application Of Quadratic Constitutive Relation And Transitional Crossflow Effects In The Wray-Agarwal Turbulence Model, Hakop Jack Nagapetyan Aug 2018

Development And Application Of Quadratic Constitutive Relation And Transitional Crossflow Effects In The Wray-Agarwal Turbulence Model, Hakop Jack Nagapetyan

Engineering and Applied Science Theses & Dissertations

Computational Fluid Dynamics (CFD) has now become an almost indispensable tool for modern engineering analysis of fluid flow over aircrafts, turbomachinery, automobiles, and many other industrial applications. Accurate prediction of turbulent flows remains a challenging problem. The most popular approach for simulating turbulent flows in complex industrial applications is based on the solution of the Reynolds-Averaged Navier-Stokes (RANS) equations. RANS equations introduce the so called “Reynolds or turbulent stresses” which are generally modeled using the Boussinesq approximation known as “Turbulence modeling.” Despite their development over a century, the turbulence models used with RANS equations still need much improvement. The first ...