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Articles 41071 - 41100 of 196022

Full-Text Articles in Engineering

Analysis Of Road Use Maintenance Agreements (Rumas), Anna Cermak Jan 2022

Analysis Of Road Use Maintenance Agreements (Rumas), Anna Cermak

Williams Honors College, Honors Research Projects

A Road Use Maintenance Agreement, also known as a RUMA, is an agreement made between a government entity and a business to put in place the set of rules that will guide the responsibilities of the business regarding the use of the entity's roads (Road use maintenance agreements RUMA, 2020). This specific type of road maintenance agreement is popularly used in the state of Ohio a the time. Most other states still operate on older ways of thinking, not capitalizing on the industry that in their area, therefore causing their road infrastructure and economies to suffer. A template agreement was …

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Matlab Model To Predict Liquid Hydrogen Spill Characteristics And Safety, Amy Gravenstein Jan 2022

Matlab Model To Predict Liquid Hydrogen Spill Characteristics And Safety, Amy Gravenstein

Williams Honors College, Honors Research Projects

The potential of using liquid hydrogen for propulsion is often undermined due to its perilous nature. Hydrogen has a wide flammability range when mixed with air (4.0 - 75.0% hydrogen) and a low ignition energy (0.019 mJ). Liquid hydrogen adds to this high risk as a cryogenic fluid that is to be maintained below -22 K. A liquid hydrogen model has been created in MATLAB that can model various spill scenarios from cryogenic liquid hydrogen vessels. This model takes into consideration the spill rate, spill temperature, air temperature, duration of spill, and air flow conditions to calculate the mass accumulation, …

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Biodegradation Of Rubber Particles In Soil: Using Acclimated Bacteria Isolated From Kansas Soil To Degrade Cryogrinds In Slurry, Shane Graham Jan 2022

Biodegradation Of Rubber Particles In Soil: Using Acclimated Bacteria Isolated From Kansas Soil To Degrade Cryogrinds In Slurry, Shane Graham

Williams Honors College, Honors Research Projects

This study investigated the viability of bioremediating rubber cryogrind using enriched indigenous bacteria. To begin the experiment, soils from three highway roadside locations in Kansas, KS 96 and West, KS 400 and 143rd, and 199th, were collected and transported to the lab to be studied. An initial soil characterization was run on the soil samples using distilled (DI) water mixture and 0.01 M CaCl2 to assess conductivity. The soils were tested to gather a baseline of the relationship between pH and conductivity and the impact of its distance from the roadside. Bacteria were isolated from …

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Induction Brazing, Austin Squire, Scott Compton, Logan Hathaway, Michael Fleming Jan 2022

Induction Brazing, Austin Squire, Scott Compton, Logan Hathaway, Michael Fleming

Williams Honors College, Honors Research Projects

Our team would like to research and explore ways of designing a portable device that uses induction heating/brazing to connect two exhaust pipes together.

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Potential Water Treatment Residual Used For Eutrophication Prevention: Varying Bake Time And Wet-Dry Release Experiments, Noor Fahoum Jan 2022

Potential Water Treatment Residual Used For Eutrophication Prevention: Varying Bake Time And Wet-Dry Release Experiments, Noor Fahoum

Williams Honors College, Honors Research Projects

A challenge faced today in water ways is the excessive growth of algae due to eutrophication. These harmful algal blooms create problems for the environment and safety concerns for the use of water for drinking purposes. An increase in limiting nutrients such as nitrogen and phosphorus are one of the factors that contribute to eutrophication. This is a concern for the Akron Water Treatment plant where preventative measures are being taken to avoid the potential formation of harmful algal blooms and the cyanotoxins they may release in the water. Through various studies, water treatment residuals (WTR) have been found to …

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Magic: The Gathering Card Virtualizer, Vincent Garbonick, Jacen C. Conlan, Jaret A. Varn Jan 2022

Magic: The Gathering Card Virtualizer, Vincent Garbonick, Jacen C. Conlan, Jaret A. Varn

Williams Honors College, Honors Research Projects

Any well-versed Magic: The Gathering (MTG) player or collector knows how difficult it can be to keep track of all cards in their collection. Some spend hours searching for that one specific card, and others are constantly scouring the internet for how much their collection costs. However, this issue does not only affect casual fans. Resale companies spend hours a day determining the costs of cards, and tournament judges painstakingly check players’ decks to ensure they are not cheating. To assist with these struggles, the design team proposed to create the MTG Card Virtualizer. This device scans MTG playing cards …

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Investigating The Mechanical Properties Of Frozen Soil Using Non-Destructive Seismic Wave Measurements, Sean Mach Jan 2022

Investigating The Mechanical Properties Of Frozen Soil Using Non-Destructive Seismic Wave Measurements, Sean Mach

Williams Honors College, Honors Research Projects

This proposed project will be dealing with investigating the mechanical properties of soil under frozen conditions. This will be done by an innovative non-destructive technology measuring the propagation of seismic waves through the frozen soils from multiple piezoelectric sensors. For the duration of this research, a freezing cell must be constructed to carry out the experimental testing. Multiple levels of saturation will be tested under the given freezing conditions. This should highlight the effect that the level of saturation will have on the propagation of seismic waves throughout the soil. Piezo-electric sensors will be placed in each layer of soil …

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Electrochemical Chloride Removal, Marcus Yudt Jan 2022

Electrochemical Chloride Removal, Marcus Yudt

Williams Honors College, Honors Research Projects

Electrochemical chloride removal (ECR) was tested to see its effectiveness in preventing corrosion on rebar samples within 3.5 wt% sodium chloride concrete. In order to do this, three scenarios were evaluated using electrochemical techniques such as cyclic potentiodynamic polarization and electrochemical impedance spectrsoscopy as well as visual inspections. The three scenarios that were evaluated were one with no chlorides present within the concrete, one that was a worst-case scenario where extreme pitting and corrosion were initiated, and one that had chlorides present and received the ECR treatment. Cyclic polarization curves showed that the ECR and reference without chlorides had similar …

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Lapnitor: A Web Service That Protects Your Laptop From Theft., Michael Ameteku Jan 2022

Lapnitor: A Web Service That Protects Your Laptop From Theft., Michael Ameteku

Williams Honors College, Honors Research Projects

Laptop theft is an issue worldwide. According to an article from 2018, Security Boulevard stated that a laptop is stolen every 53 seconds. Using a laptop's camera, we can monitor the surroundings of the laptop and reduce a laptop's probability of being stolen. According to the University of Pittsburgh, a laptop has a 1-in- 10 chance of being stolen and nearly half of these thefts occur in offices or classrooms. These thefts mostly occur when a laptop owner leaves their device unattended for a certain period of time to maybe go visit the restroom or attend to a call when …

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Development Of Co2 Capture Method Via Polyurethane-Amine Sorbent In Vsa, Samantha Starkey, David S. Rinehart Jan 2022

Development Of Co2 Capture Method Via Polyurethane-Amine Sorbent In Vsa, Samantha Starkey, David S. Rinehart

Williams Honors College, Honors Research Projects

With increases in extreme weather and global temperatures, research is delving into CO2 capture to help reverse climate change. This project explored utilizing vacuum swing adsorption (VSA) for CO2 capture and release. VSA uses a sorbent, in this case amine sorbents, to capture CO­­2 from air and subsequently removes it via vacuum. Polyurethane (PU) foam was investigated as a potential matrix for amine sorbents to increase exposure of CO2 capturing amines to air by utilizing its porous structure. PU mixing studies were conducted to determine the feasibility of mixing PU foam with amines and coating foams …

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Innovated Manual Wheelchair Propulsion, Jacob Eveleth, Abigail Steineman, James Murray, Garrett Best Jan 2022

Innovated Manual Wheelchair Propulsion, Jacob Eveleth, Abigail Steineman, James Murray, Garrett Best

Williams Honors College, Honors Research Projects

The goal of this project is to provide a manual wheelchair propulsion system that provides an easier way of moving the chair for the user. Our already-defined set of constraints and goals provides a clear end-goal for our group in accomplishing this task. We plan to have a 3D CAD model of the design by the end of the Spring 2022 semester. The first half of the Fall 2022 semester will be dedicated to developing a plan for prototyping, and the second half of the semester we plan to have the prototype created for use. So far, we have utilized …

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Efficient And Accurate Cordic Pipelined Architecture Chip Design Based On Binomial Approximation For Biped Robot, Rih-Lung Chung, Yen Hsueh, Shih-Lun Chen, Patricia Angela R. Abu Jan 2022

Efficient And Accurate Cordic Pipelined Architecture Chip Design Based On Binomial Approximation For Biped Robot, Rih-Lung Chung, Yen Hsueh, Shih-Lun Chen, Patricia Angela R. Abu

Department of Information Systems & Computer Science Faculty Publications

Recently, much research has focused on the design of biped robots with stable and smooth walking ability, identical to human beings, and thus, in the coming years, biped robots will accomplish rescue or exploration tasks in challenging environments. To achieve this goal, one of the important problems is to design a chip for real-time calculation of moving length and rotation angle of the biped robot. This paper presents an efficient and accurate coordinate rotation digital computer (CORDIC)-based efficient chip design to calculate the moving length and rotation angle for each step of the biped robot. In a previous work, the …

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Identifying Code Reading Strategies In Debugging Using Sta With A Tolerance Algorithm, Christine Lourrine S. Tablatin, Ma. Mercedes T. Rodrigo Jan 2022

Identifying Code Reading Strategies In Debugging Using Sta With A Tolerance Algorithm, Christine Lourrine S. Tablatin, Ma. Mercedes T. Rodrigo

Department of Information Systems & Computer Science Faculty Publications

The purpose of this study was to identify the common code reading strategies of the high and low performing students engaged in a debugging task. Using Scanpath Trend Analysis (STA) with a tolerance on eye tracking data, common scanpaths of high and low performing students were generated. The common scanpaths revealed differences in the code reading patterns and code reading strategies of high and low performing students. High performing students follow a bottom-up code reading strategy when debugging complex programs with logical and semantic errors. A top-down code reading strategy is employed when debugging programs with simple control structures, few …

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Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo Jan 2022

Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo

Department of Information Systems & Computer Science Faculty Publications

Pair programming is a model of collaborative learning. It has become a well-known pedagogical practice in teaching introductory programming courses because of its potential benefits to students. This study aims to investigate pair patterns in the context of pair program tracing and debugging to determine what characterizes collaboration and how these patterns relate to success, where success is measured in terms of performance task scores. This research used eye-tracking methodologies and techniques such as cross-recurrence quantification analysis. The potential indicators for pair success were used to create a model for predicting pair success. Findings suggest that it is possible to …

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The Uses Of A Dual-Band Corrugated Circularly Polarized Horn Antenna For 5g Systems, Chih-Kai Liu, Wei-Yuan Chiang, Pei-Zong Rao, Pei-Hsiu Hung, Shih-Hung Chen, Chiung-An Chen, Liang-Hung Wang, Patricia Angela R. Abu, Shih-Lun Chen Jan 2022

The Uses Of A Dual-Band Corrugated Circularly Polarized Horn Antenna For 5g Systems, Chih-Kai Liu, Wei-Yuan Chiang, Pei-Zong Rao, Pei-Hsiu Hung, Shih-Hung Chen, Chiung-An Chen, Liang-Hung Wang, Patricia Angela R. Abu, Shih-Lun Chen

Department of Information Systems & Computer Science Faculty Publications

This paper presents the development of a wide-beam width, dual-band, omnidirectional antenna for the mm-wave band used in 5G communication systems for indoor coverage. The 5G indoor environment includes features of wide space and short range. Additionally, it needs to function well under a variety of circumstances in order to carry out its diverse set of network applications. The waveguide antenna has been designed to be small enough to meet the requirements of mm-wave band and utilizes a corrugated horn to produce a wide beam width. Additionally, it is small enough to integrate with 5G communication products and is easy …

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Non-Parametric Stochastic Autoencoder Model For Anomaly Detection, Raphael B. Alampay, Patricia Angela R. Abu Jan 2022

Non-Parametric Stochastic Autoencoder Model For Anomaly Detection, Raphael B. Alampay, Patricia Angela R. Abu

Department of Information Systems & Computer Science Faculty Publications

Anomaly detection is a widely studied field in computer science with applications ranging from intrusion detection, fraud detection, medical diagnosis and quality assurance in manufacturing. The underlying premise is that an anomaly is an observation that does not conform to what is considered to be normal. This study addresses two major problems in the field. First, anomalies are defined in a local context, that is, being able to give quantitative measures as to how anomalies are categorized within its own problem domain and cannot be generalized to other domains. Commonly, anomalies are measured according to statistical probabilities relative to the …

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Design And Synthesis Of Α-Anomeric Diacetylene-Containing Glycosides As Photopolymerizable Molecular Gelators, Guijun Wang, Dan Wang, Anji Chen, Ifeanyi S. Okafor, Lalith Palitha Samankumara Jan 2022

Design And Synthesis Of Α-Anomeric Diacetylene-Containing Glycosides As Photopolymerizable Molecular Gelators, Guijun Wang, Dan Wang, Anji Chen, Ifeanyi S. Okafor, Lalith Palitha Samankumara

Chemistry & Biochemistry Faculty Publications

Glycolipids with diacetylene functional groups are fascinating compounds with many practical uses. Among these, diacetylene-containing gelators are especially important because they can form photopolymerizable gels, which are useful stimuli-responsive materials. Inspired by the unique properties of diacetylene-containing gelators and to understand the structural influences especially the location of the diacetylene functional groups on the self-assembling properties, a series of 15 novel N-acetyl-d-glucosamine derivatives with the diacetylene functional group introduced at the anomeric position were designed and synthesized. The diacetylene function is attached to the sugar through α-glycosylation with the distance from the anomeric oxygen being varied from one, two, …

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Rational Design Of Metal-Organic Frameworks (Mofs)-Based Functional Materials Towards Better Air Quality, Zan Zhu Jan 2022

Rational Design Of Metal-Organic Frameworks (Mofs)-Based Functional Materials Towards Better Air Quality, Zan Zhu

Theses and Dissertations

Air pollution is a major threat to environmental safety and public health. Volatile organic compounds (VOCs), particulate matter (PM), and airborne microorganisms are three typical air pollutants. Conventional strategies to prevent and mitigate air pollution have been employed, which, however, are generally passive. For instance, VOC sensing through solid-state devices is a conventional approach, which, however, is not capable of capturing and removing VOCs. On the other hand, air filters and face masks are useful equipment to protect people from inhaling PM and airborne microorganisms. But most commercial filters can only capture them on the surfaces, which may cause secondary …

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Novel Microfabricated Systems To Elucidate The Role Of Anisotropic Stiffness In The Tumor Microenvironment, Jiten Narang Jan 2022

Novel Microfabricated Systems To Elucidate The Role Of Anisotropic Stiffness In The Tumor Microenvironment, Jiten Narang

Theses and Dissertations

Cancer is the second leading cause of death in women and late stage (metastatic) cancers have abysmal survival rates compared to early stage regional cases (27% vs 86%). As a tumor grows, the surrounding extracellular matrix (ECM) is reorganized into a dense, collagen rich matrix. The new matrix of aligned collagen fibers provides unique mechanical cues such as anisotropic stiffness and contact guidance. Matrix turnover also constricts local vasculature and restricts delivery of key nutrients and signaling molecules to malignant cells to outside the tumor creating a chemotactic gradient from outside to inside. In this work, we developed a novel …

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Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar Jan 2022

Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar

Theses and Dissertations

Chronic pain (CP) is a significant contributor to disability and disease burden globally. In 2019, approximately 50.2 million adults (20.4% of the US population) experienced chronic pain, contributing to $560-635 billion in direct medical costs. In addition, the worldwide prevalence of diabetes mellitus has reached epidemic proportions and is set to increase to 629 million by 2045. Almost 50% of patients with diabetes present with diabetic neuropathy (DN), and one in five patients with diabetes presents with painful DN (pDN) which is the most common cause of neuropathic pain (NP) in the US. Symptomatic treatment is the mainstay of management …

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Low Loss Plasmon-Assisted Integrated Photonics, Dhruv Fomra Jan 2022

Low Loss Plasmon-Assisted Integrated Photonics, Dhruv Fomra

Theses and Dissertations

Photonic integrated circuits (PICs), semiconductor chips with both photonic and electronic elements, are seeing rapid development and have the potential to transform several industries, such as autonomous driving, computing, telecommunication and quantum networks. However, realization and wide adoption of PICs across the various fields faces a key challenge – soze disparity between electronic (~0.01 um) and photonic components (~100’s of um). Plasmonics, a technology which confines light to the interface of metals and dielectrics, has a potential to address challenges. In particular, it has been shown to led to smaller devices (~10 um or less), enabling higher density optical circuits …

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Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang Jan 2022

Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang

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5th generation wireless systems (5G) have expanded frequency band coverage with the low-band 5G and mid-band 5G frequencies spanning 600 MHz to 4 GHz spectrum. This dissertation focuses on a microelectronic implementation of CMOS 65 nm design of an All-Digital Phase Lock Loop (ADPLL), which is a critical component for advanced 5G wireless transceivers. The ADPLL is designed to operate in the frequency bands of 600MHz-930MHz, 2.4GHz-2.8GHz and 3.4GHz-4.2GHz. Unique ADPLL sub-components include: 1) Digital Phase Frequency Detector, 2) Digital Loop Filter, 3) Channel Bank Select Circuit, and 4) Digital Control Oscillator. Integrated with the ADPLL is a 90-degree active …

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Building An Understanding Of Human Activities In First Person Video Using Fuzzy Inference, Bradley A. Schneider Jan 2022

Building An Understanding Of Human Activities In First Person Video Using Fuzzy Inference, Bradley A. Schneider

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Activities of Daily Living (ADL’s) are the activities that people perform every day in their home as part of their typical routine. The in-home, automated monitoring of ADL’s has broad utility for intelligent systems that enable independent living for the elderly and mentally or physically disabled individuals. With rising interest in electronic health (e-Health) and mobile health (m-Health) technology, opportunities abound for the integration of activity monitoring systems into these newer forms of healthcare. In this dissertation we propose a novel system for describing ’s based on video collected from a wearable camera. Most in-home activities are naturally defined by …

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Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris Jan 2022

Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris

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A method for the beam forming control of an array of reconfigurable antennas is presented. The method consists of using two parallel convolutional neural networks (CNNs) to analyze a desired radiation pattern image, or mask, and provide a suggestion for the reconfigurable element state, array shape, and steering weights necessary to obtain the radiation pattern. This research compares beam forming systems designed for three distinct element types: a patch antenna, a reconfigurable square spiral antenna restricted to a single reconfigurable state, and the fully reconfigurable square spiral. The parametric sweeps for the design of the CNNs are presented along with …

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Secure Authenticated Key Exchange For Enhancing The Security Of Routing Protocol For Low-Power And Lossy Networks, Sarah Mohammed Alzahrani Jan 2022

Secure Authenticated Key Exchange For Enhancing The Security Of Routing Protocol For Low-Power And Lossy Networks, Sarah Mohammed Alzahrani

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The current Routing Protocol for Low Power and Lossy Networks (RPL) standard provides three security modes Unsecured Mode (UM), Preinstalled Secure Mode (PSM), and Authenticated Secure Mode (ASM). The PSM and ASM are designed to prevent external routing attacks and specific replay attacks through an optional replay protection mechanism. RPL's PSM mode does not support key replacement when a malicious party obtains the key via differential cryptanalysis since it considers the key to be provided to nodes during the configuration of the network. This thesis presents an approach to implementing a secure authenticated key exchange mechanism for RPL, which ensures …

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Molecular Dynamics Simulation Study Of A Polymer Droplet Transport Over An Array Of Spherical Nanoparticles, Anish Thomas Jan 2022

Molecular Dynamics Simulation Study Of A Polymer Droplet Transport Over An Array Of Spherical Nanoparticles, Anish Thomas

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This study uses molecular dynamics simulations to evaluate the dynamic behavior of a partially wetting polymer droplet driven over a nanostructured interface. We consider the bead-spring model to represent a polymeric liquid that partially wets a rough surface composed of a periodic array of spherical particles. Results show that at sufficiently small values of external force, the droplet remains pinned at the particle's surface, whereas above the threshold its motion consists of alternating periods of pinning and rapid displacements between neighboring particles. The latter process involves large periodic variation of the advancing and receding contact angles due to the attachment …

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Printing, Characterization, And Mechanical Testing Of Additively Manufactured Refractory Metal Alloys, Brianna M. Sexton Jan 2022

Printing, Characterization, And Mechanical Testing Of Additively Manufactured Refractory Metal Alloys, Brianna M. Sexton

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Refractory metal alloys in the tungsten molybdenum rhenium ternary system were additively manufactured using laser power bed fusion. Four ternary alloys with varying concentrations of tungsten, molybdenum, and rhenium were manufactured and manufactured again with an addition of 1 wt% hafnium carbide. Samples were heat treated to heal cracks, reduce porosity, and reduce inhomogeneity. Material microstructure was characterized before and after heat treatment using microscopy, energy dispersive x-ray spectroscopy, and electron backscatter diffraction mapping. Mechanical testing was conducted on both three-point bend specimens and compression specimens, resulting in maximum bending strengths of 677.86 MPa, and maximum compression 0.2% yield strengths …

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Realistic Virtual Human Character Design Strategy And Experience For Supporting Serious Role-Playing Simulations On Mobile Devices, Sindhu Kumari Jan 2022

Realistic Virtual Human Character Design Strategy And Experience For Supporting Serious Role-Playing Simulations On Mobile Devices, Sindhu Kumari

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Promoting awareness of social determinants of health (SDoH) among healthcare providers is important to improve the patient care experience and outcome as it helps providers understand their patients in a better way which can facilitate more efficient and effective communication about health conditions. Healthcare professionals are typically educated about SDoH through lectures, questionaries, or role-play-based approaches; but in today’s world, it is becoming increasingly possible to leverage modern technology to create more impactful and accessible tools for SDoH education. Wright LIFE (Lifelike Immersion for Equity) is a simulation-based training tool especially created for this purpose. It is a mobile app …

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Design, Analysis, And Optimization Of Traffic Engineering For Software Defined Networks, Mohammed Ibrahim Salman Jan 2022

Design, Analysis, And Optimization Of Traffic Engineering For Software Defined Networks, Mohammed Ibrahim Salman

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Network traffic has been growing exponentially due to the rapid development of applications and communications technologies. Conventional routing protocols, such as Open-Shortest Path First (OSPF), do not provide optimal routing and result in weak network resources. Optimal traffic engineering (TE) is not applicable in practice due to operational constraints such as limited memory on the forwarding devices and routes oscillation. Recently, a new way of centralized management of networks enabled by Software-Defined Networking (SDN) made it easy to apply most traffic engineering ideas in practice. \par Toward creating an applicable traffic engineering system, we created a TE simulator for experimenting …

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A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean Jan 2022

A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean

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One of the technological challenges in the widespread application of additive manufacturing is the formation of undesired material microstructure and defects. Specifically, in metal additive manufacturing, the microstructural formation of columnar grains in Ti-6Al-4V is common and results in anisotropic mechanical properties and a reduction in properties such as ductility and endurance limit. This work presents the application of hexagonal and circular arrays of synchronized lasers to alter the microstructure of Ti-6Al-4V in favor of equiaxed grains. An anisotropic heat transfer model obtains the temporal/spatial temperature distribution and constructs the solidification map for various process parameters, including laser power, laser …

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