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Articles 4471 - 4500 of 9983
Full-Text Articles in Engineering
Understanding Diffusion And Electrochemical Reduction Of Li+ Ions In Liquid Lithium Metal Batteries, Witness Martin, Yang Tian, Jie Xiao
Understanding Diffusion And Electrochemical Reduction Of Li+ Ions In Liquid Lithium Metal Batteries, Witness Martin, Yang Tian, Jie Xiao
Chemistry & Biochemistry Faculty Publications and Presentations
Lithium metal has drawn significant interest as an anode material for next generation lithium (Li) batteries. However, due to its propensity to form dendrites in commonly used electrolytes during repeated cycling, it has not yet been commercialized in secondary batteries. The formation of a Li protrusion is determined by the relative speed of Li+ ions being reduced and how fast they can be replenished in the vincinity of electrode. However, it is very difficult to quantify such kinetic parameters of Li+ ion in different electrolytes, not mentioning the identification of the desired electrolyte recipe to mitigate Li dendrite formation. Herein, …
Data Mining Of Unstructured Textual Information In Transportation Safety Domain: Exploring Methods, Opportunities And Limitations, Keneth Morgan Kwayu
Data Mining Of Unstructured Textual Information In Transportation Safety Domain: Exploring Methods, Opportunities And Limitations, Keneth Morgan Kwayu
Dissertations
The unprecedented increase in volume and influx of structured and unstructured data has overwhelmed conventional data management system capabilities in organizing, analyzing, and procuring useful information in a timely fashion. Structured data sources have a pre-defined pattern that makes data preprocessing and information retrieval tasks relatively easy for the current technologies that have been designed to handle structured and repeatable data. Unlike structured data, unstructured data usually exists in an unorganized format that offers no or little insight unless indexed and stored in an organized fashion. The inherent format of unstructured data exacerbates difficulties in data preprocessing and information extraction. …
Quantum Transport Of The 2d Surface State In A Nonsymmorphic Semimetal, Xue Liu, Jin Hu, Jiang Wei, Chunlei Yue, Sergey V. Erohin, Yanglin Zhu, Abin Joshy, Jinyu Liu, Ana M. Sanchez, David Graf, Pavel B. Sorokin, Zinqiang Mao
Quantum Transport Of The 2d Surface State In A Nonsymmorphic Semimetal, Xue Liu, Jin Hu, Jiang Wei, Chunlei Yue, Sergey V. Erohin, Yanglin Zhu, Abin Joshy, Jinyu Liu, Ana M. Sanchez, David Graf, Pavel B. Sorokin, Zinqiang Mao
Physics Faculty Publications and Presentations
In a topological semimetal with Dirac or Weyl points, the bulk-boundary correspondence principle predicts a gapless edge mode if the essential symmetry is still preserved at the surface. The detection of such topological surface state has been considered as the fingerprint prove for crystals with nontrivial topological bulk band. On the contrary, it has been proposed that even with symmetry broken at the surface, a new surface band can emerge in nonsymmorphic topological semimetals. The symmetry reduction at the surface lifts the bulk band degeneracies and produces an unusual “floating” surface band with trivial topology. Here, we first report quantum …
Bi-Directional Kerr-Lens Mode-Locked Titanium Sapphire Laser, Ricky Arnold, Stratos Koutroulis, Dylan Meyer
Bi-Directional Kerr-Lens Mode-Locked Titanium Sapphire Laser, Ricky Arnold, Stratos Koutroulis, Dylan Meyer
Mechanical Engineering Senior Theses
Precision near-infrared absorption spectroscopy is a highly desired scientific method, but the blooming technology has not yet come to fruition. Field deployments are limited, and some methods come with limitations that hamper the viability. The laser cavity completed for this thesis project is a single cavity Dual Comb Spectroscopy laser, which improves myriad limiting characteristics of previous lasers in this application. Crucially, it can produce two simultaneous pulse trains with unique repetition rates. The laser cavity has been designed, built, and aligned for improved stability, including vibrational, noise, and thermal control. The design, analysis, and results of a dual comb …
Enhance Portable Radiograph For Fast And High Accurate Covid-19 Monitoring, Ngan Le, James Sorensen, Toan Bui, Arabinda Choudhary, Khoa Luu, Hien Nguyen
Enhance Portable Radiograph For Fast And High Accurate Covid-19 Monitoring, Ngan Le, James Sorensen, Toan Bui, Arabinda Choudhary, Khoa Luu, Hien Nguyen
Computer Science and Computer Engineering Faculty Publications and Presentations
This work aimed to assist physicians by improving their speed and diagnostic accuracy when interpreting portable CXRs as well as monitoring the treatment process to see whether a patient is improving or deteriorating with treatment. These objectives are in especially high demand in the setting of the ongoing COVID-19 pandemic. With the recent progress in the development of artificial intelligence (AI), we introduce new deep learning frameworks to align and enhance the quality of portable CXRs to be more consistent, and to more closely match higher quality conventional CXRs. These enhanced portable CXRs can then help the doctors provide faster …
Toward Cost-Effective Residential Energy Reduction And Community Impacts: A Data-Based Machine Learning Approach, Adel Naji, Badr Al Tarhuni, Jun-Ki Choi, Salahaldin Alshatshati, Seraj Ajena
Toward Cost-Effective Residential Energy Reduction And Community Impacts: A Data-Based Machine Learning Approach, Adel Naji, Badr Al Tarhuni, Jun-Ki Choi, Salahaldin Alshatshati, Seraj Ajena
Mechanical and Aerospace Engineering Faculty Publications
Many U.S. utilities incentivize residential energy reduction through rebates, often in response to state mandates for energy reduction or from a desire to reduce demand to mitigate the need to grow generating assets. The assumption built into incentive programs is that the least efficient residences will be more likely take advantage of the rebates. This, however, is not always the case. The main goal of this study was to determine the potential for prioritized incentivization, i.e., prioritizing incentives that deliver the greatest energy savings per investment through an entire community. It uses a data mining approach that leverages known building …
Adjustable Head Tube Angle Headset, Glenn Petersen, Ben Harper, Josh Martin, Dylan Prins
Adjustable Head Tube Angle Headset, Glenn Petersen, Ben Harper, Josh Martin, Dylan Prins
Mechanical Engineering
This final design review report describes the design, manufacture, and test process of a bicycle headset capable of quickly and easily adjusting the effective head tube angle. The evolution of mountain bike geometry has forced bike designers to compromise between climbing and descending performance when choosing a head tube angle. A headset capable of quickly adjusting the effective head tube angle would allow riders to optimize their bike’s geometry for different stages of riding. This report details the research, idea generation, concept development and selection, design, manufacturing, and testing of our adjustable head tube angle headset.
Agent-Based Semantic Role Mining For Intelligent Access Control In Multi-Domain Collaborative Applications Of Smart Cities, Rubina Ghazal, Ahmad Kamran Malik, Basit Raza, Nauman Qadeer, Nafees Qamar, Sajal Bhatia
Agent-Based Semantic Role Mining For Intelligent Access Control In Multi-Domain Collaborative Applications Of Smart Cities, Rubina Ghazal, Ahmad Kamran Malik, Basit Raza, Nauman Qadeer, Nafees Qamar, Sajal Bhatia
School of Computer Science & Engineering Faculty Publications
Significance and popularity of Role-Based Access Control (RBAC) is inevitable; however, its application is highly challenging in multi-domain collaborative smart city environments. The reason is its limitations in adapting the dynamically changing information of users, tasks, access policies and resources in such applications. It also does not incorporate semantically meaningful business roles, which could have a diverse impact upon access decisions in such multi-domain collaborative business environments. We propose an Intelligent Role-based Access Control (I-RBAC) model that uses intelligent software agents for achieving intelligent access control in such highly dynamic multi-domain environments. The novelty of this model lies in using …
Flywheel Fanny Pack Balance Assist, Ella Joy Mahood, Jason Scott Provol, Raymond Ming Tseng
Flywheel Fanny Pack Balance Assist, Ella Joy Mahood, Jason Scott Provol, Raymond Ming Tseng
Biomedical Engineering
The aim of this project is to develop a wearable device that will provide support to a balance impaired individual. The device will be predicated on the principle of gyroscopes. It will include a rapidly spinning flywheel, which will resist any changes to spatial orientation.
Adjustable Height Pedestal Grinder Stand, Josef Zagorski, Zachary Wedel, Michael Sitar, Daniel Zevenbergen
Adjustable Height Pedestal Grinder Stand, Josef Zagorski, Zachary Wedel, Michael Sitar, Daniel Zevenbergen
Mechanical Engineering
Pedestal grinders are one of the most common machines found in machine shops today. The current industry standard for mounting a grinder is on a fixed single pillar, cast iron pedestal. A fixed pedestal allows for no vertical adjustment for shop users of different sizes and is a safety hazard. This report further defines this problem and proposes an iterative design process to meet the needs and wants of the customer. The adjustable-height pedestal grinder stand Senior Project team used this problem and design process to successfully complete the project within the allotted time. The first major deliverable and milestone …
Standardizing 1ru Chassis To Pcba Interfaces, Bryce J. Mcneil, Leia K. Tashiro, John H. Liu, Sarika L. Singhal
Standardizing 1ru Chassis To Pcba Interfaces, Bryce J. Mcneil, Leia K. Tashiro, John H. Liu, Sarika L. Singhal
Mechanical Engineering
Cisco currently designs a variety of custom chassis for different types of servers, routers, and switches. Our senior design project aims to reduce the number of custom chassis Cisco develops by standardizing the perimeter mounting locations for the printed circuit board assembly on the chassis. The purpose of this report is to document our selected project direction and support the decisions with appropriate evidence. In addition to research on the customer’s needs, the product, and the technical background used to understand the project scope, our group has come up with a way to analyze and compare mounting locations for various …
Bicycle Headset With Adjustable Spring Rate, Andrew W. Drees, Jonah Masumoto, Camden R.S. Boshart, Matthew B. Mounteer
Bicycle Headset With Adjustable Spring Rate, Andrew W. Drees, Jonah Masumoto, Camden R.S. Boshart, Matthew B. Mounteer
Mechanical Engineering
Fork flop can play an important role in the performance of a mountain bike. This phenomenon of fork flop is known as the tendency that the front wheel of a bike wants to flop over to one side when moving slowly. The fork flop experienced on a bicycle changes with the geometry of the bike, but our team sought to change the fork flop experienced through an adjustable internal spring design that attaches to the bicycle instead. From our research, we decided to utilize torsion springs as the method for mitigating fork flop. We also decided to use load cells …
Sourceamerica Design Challenge Accessible Kitting And Packaging Station, Christopher Wijaya Tan, Keanau Rick Robin, Kyle Huawei Chuang, Ashley Humpal
Sourceamerica Design Challenge Accessible Kitting And Packaging Station, Christopher Wijaya Tan, Keanau Rick Robin, Kyle Huawei Chuang, Ashley Humpal
Mechanical Engineering
This document entails our research, design, proposed development, and testing process for solving the 2020 SourceAmerica collegiate design challenge. Our team, “Just Kitting”, is composed of four Mechanical Engineering students from California Polytechnic San Luis Obispo. The design challenge requires us to create a device that will help improve the quality of life and productivity of people with disabilities working in the kitting and packaging industry. This document includes our background research and information received from various interviews with our sponsor and others who have experience working with disabilities. Using this information, we refined our problem statement to focus on …
Tensile Testing Environmental Chamber – Structural, Michael Ingel, Erik Soldenwagner, Austin Marshall, Lauren Schirle
Tensile Testing Environmental Chamber – Structural, Michael Ingel, Erik Soldenwagner, Austin Marshall, Lauren Schirle
Mechanical Engineering
Environmental chambers for tensile testing machines are used to study how a multitude of materials behave in extreme temperatures. These chambers provide the necessary information to innovate cutting edge technology for materials in fields such as aerospace. These chambers are often heavy and expensive requiring a significant amount of time and money just in the installation process alone. This report will serve to outline and define the design and fabrication of an environmental chamber, conducted by a team of four senior mechanical engineering students at California Polytechnic State University, San Luis Obispo. The goals of the project include a low-weight …
3-Axis Reaction Wheel System For Cubesats, Alexandra Mae Lee, Daniel Leon, Christopher Pablo Casillas, Rose Mccarver
3-Axis Reaction Wheel System For Cubesats, Alexandra Mae Lee, Daniel Leon, Christopher Pablo Casillas, Rose Mccarver
Mechanical Engineering
Reaction wheels are a common, but expensive, component used in CubeSats, that can accurately position a satellite using an imparted momentum (or impulse) from a rotating flywheel to adjust a satellite’s attitude. This document serves as the final design review and report for the 3-Axis Reaction Wheel Senior Design Project in the Mechanical Engineering Department of California Polytechnic State University, San Luis Obispo. The goal of this project is to produce a functional, low-cost 3-axis reaction wheel system based on previous research done by a master’s student at Cal Poly to be implemented in future CubeSats in the Cal Poly …
Blds Pressure Belt, Hailey Earnest, Sean Casteel, Benjamin Bons, Biren Rama
Blds Pressure Belt, Hailey Earnest, Sean Casteel, Benjamin Bons, Biren Rama
Mechanical Engineering
Dr. Westphal has a Boundary Layer Data System (BLDS) that is used to take pressure measurements on the surface of the aircraft. Our team has created a design and manufacturing method for producing the corresponding pressure belt that attaches to Dr. Westphal's system to obtain pressure data.
Cal Poly Wind Power: Wind Turbine Prototype, Sophie A. Spencer, Maggie Nevrly, Michael Reyna, Loi Q. Nguyen
Cal Poly Wind Power: Wind Turbine Prototype, Sophie A. Spencer, Maggie Nevrly, Michael Reyna, Loi Q. Nguyen
Mechanical Engineering
The Cal Poly Wind Power (CPWP) club is competing in the Collegiate Wind Competition (CWC) hosted by the National Renewable Energy Laboratory (NREL). The CWC is hosted annually by NREL to increase the number of skilled workers prepared to work in the wind energy industry. Our senior project team is one of several design teams contributing to the CPWP prototype turbine design including the pitching mechanism, blade design, generator, and shaft. The scope of this project is to design the yaw mechanism, tower, and nacelle. The goal is to create components that function well with other planned components and are …
Adaptive Vehicle Control, Brian L. Finger, Maria Vargas, Jacob T. Larson, Christopher J. Villa
Adaptive Vehicle Control, Brian L. Finger, Maria Vargas, Jacob T. Larson, Christopher J. Villa
Mechanical Engineering
This report presents the final design for our device made for Mrs. Laura Jagels. Mrs. Jagels, who has an above the knee amputation, needed a device that would allow her to operate a manual car in a safe and reliable way that still gives her the traditional driving experience. This report takes into consideration the shortcomings of current market devices that enable amputees to operate vehicles. From this research and through interviews with Mrs. Jagels, we were able to decide on our device specifications, giving us a basis to objectively evaluate designs. Ideation and concept prototype building was performed for …
Controlling Locomotion Of A Robotic Leg, Tai K. Mitchell, Connor Bush, Patrick Ward, Ben Spin
Controlling Locomotion Of A Robotic Leg, Tai K. Mitchell, Connor Bush, Patrick Ward, Ben Spin
Mechanical Engineering
Dr. Xing and Professor Refvem are working to research and develop a quadruped robot that is capable of basic movements including walking, running, and jumping. As senior project group F-11, we are joining a team of engineers to assist in the development of the quadruped. Our team was tasked with creating a mathematical model, designing a control method, and implementing that control method for the quadruped's legs in Simulink. This will allow both current and future students to understand the response of the system and provide a building point for future researchers to create working quadrupedal robots. This report documents …
Saver (Surface Autonomous Vehicle For Emergency Rescue), Tyler Jorgensen, Ethan Miller, Josephine Isaacson, Joshua Hoye
Saver (Surface Autonomous Vehicle For Emergency Rescue), Tyler Jorgensen, Ethan Miller, Josephine Isaacson, Joshua Hoye
Mechanical Engineering
This document serves to introduce the design team and their competition challenge, as well as to detail the results of the project. The original design challenge was the NASA Micro-g NExT’s SAVER (Surface Autonomous Vehicle for Emergency Rescue) competition; we were tasked with developing a self-driving water vehicle capable of delivering supplies to Orion astronauts separated from the rest of their crew in the case of a maritime emergency. However, we were not selected to go forward in this competition and thus we decided to scale down the size of the SAVER device to shift the focus of the project …
Vibration Isolation For Scanning Tunneling Microscope, Seth Ewing, Ryan Mcmullen, Jason Behrens, Stephen Deherrera
Vibration Isolation For Scanning Tunneling Microscope, Seth Ewing, Ryan Mcmullen, Jason Behrens, Stephen Deherrera
Mechanical Engineering
Scanning Tunneling Microscopy (STM) works by scanning a fine metal wire over a conductive sample in order to image samples on the atomic level. The microscope uses a feedback loop with a PID controller to maintain a constant tunneling current between the sample and the tip. In order to obtain clear imaging at the atomic level, the microscope and the sample need to be isolated from external vibrations in a vacuum chamber. The scope for this project is to build and test a single-stage vibration isolation system that effectively attenuates the amplitude of external vibrations acting on the microscope. This …
Scitechatorium, Esther Hurst, Emma Salam, Nejad Harara, Felipe Dejesus
Scitechatorium, Esther Hurst, Emma Salam, Nejad Harara, Felipe Dejesus
Mechanical Engineering
The Bellevue-Santa Fe Charter School SciTechatorium needs a new educational exhibit for its K-6th grade students. The exhibit must be safe, engaging, and exciting for the students to use, and will ideally introduce students to the topics of Science, Mathematics, Engineering, Art, and Technology (STEAM) concepts. The team has investigated some of the most popular science museums from around the nation, as well as several popular children’s educational toys. This research revealed a need for hands on, focused exhibits to provide an effective educational experience. Many of our favorite existing exhibits give students an opportunity to fail in a safe …
Autonomous Tennis Ball Collector, Frances Erin Belcher, Michael Wai-Chun Yiu, Matthew David Hoffman, Alex Boyko Petrov, Robert E. Luttrell
Autonomous Tennis Ball Collector, Frances Erin Belcher, Michael Wai-Chun Yiu, Matthew David Hoffman, Alex Boyko Petrov, Robert E. Luttrell
Mechanical Engineering
Practicing tennis often involves hitting many tennis balls from one side of the court to the other without an opponent to hit the balls back. In training sessions like these, the task of collecting the balls is laborious when performed manually. The objective of this project is to develop a robotic tennis ball collector that can automatically collect the balls from one side of the court so that the player can rest rather than collect the balls manually. This document outlines the process of designing such a robot. Included in this report is background research, prototype, and concept modeling, along …
Unmanned Research Raft, Jacob Davis, Andrew Fleming, Luke Vickerman, Kahye Yu
Unmanned Research Raft, Jacob Davis, Andrew Fleming, Luke Vickerman, Kahye Yu
Mechanical Engineering
This document serves as the Final Design Review report for the design team conducting the research raft design project for Lawrence Livermore National Lab (LLNL). Our team has taken on a project to design a new research raft for LLNL.
The current rafts are suitable, but engineers have modified and altered the rafts to add more features as needed. This has led to a raft that accomplishes mission goals, but still has room for streamlining. The battery technology has also improved. Our goals were to redesign the raft from the ground up, reducing the size and weight. We also wanted …
A Study Of Implementation Methodologies For Distributed Real Time Collaboration, Lauren A. Craft
A Study Of Implementation Methodologies For Distributed Real Time Collaboration, Lauren A. Craft
Master's Theses
Collaboration drives our world and is almost unavoidable in the programming industry. From higher education to the top technological companies, people are working together to drive discovery and innovation. Software engineers must work with their peers to accomplish goals daily in their workplace. When working with others there are a variety of tools to choose from such as Google Docs, Google Colab and Overleaf. Each of the aforementioned collaborative tools utilizes the Operational Transform (OT) technique in order to implement their real time collaboration functionality. Operational transform is the technique seen amongst most if not all major collaborative tools in …
Me-Em Enewsbrief, June 2021, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Me-Em Enewsbrief, June 2021, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical and Aerospace Engineering eNewsBrief
No abstract provided.
Design And Fabrication Of Zinc Oxide Optofluidic Laser Elements, Kyle T. Bodily
Design And Fabrication Of Zinc Oxide Optofluidic Laser Elements, Kyle T. Bodily
Theses and Dissertations
This thesis systematically goes through the derivation, simulation, and experimentation of Zinc Oxide optofluidic micro laser elements. Single and coupled ring resonators were simulated to show single mode transmission as well as enhanced coupling capabilities when surrounded by high refractive index liquid. Devices with diameters ranging from 100-500 µm were successfully fabricated inexpensively through standard cleanroom procedures. The devices were tested using two different pump laser systems. Testing included such factors as high pump intensity, various angles of excitation, and low temperature. In all cases PL emission was observed and recorded.
Feasibility Study Of Radio Frequency Microelectromechanical Filters For Space Operation, Karanvir Singh
Feasibility Study Of Radio Frequency Microelectromechanical Filters For Space Operation, Karanvir Singh
Theses and Dissertations
Piezoelectric contour mode resonator technology has the unique advantage of combining low motional resistance with the ability to define multiple frequencies on the same substrate. Contour mode resonators can be mechanically coupled together to form robust band-pass filters for the next generation of GPS satellites with extreme size reduction compared to electrically coupled filters. Piezoelectric zinc oxide (ZnO) contour mode resonators have the potential for monolithic integration with current ZnO transistor further reducing size, power consumption, and cost of filter modules. Barium strontium titanate (BST) contour mode resonators have incredible frequency tunability due to the fundamental nature of the thin …
Examining The Influence Of Source Dependence On Supplier Performance In The Usaf Organic Supply Chain, Thomas A. Counter
Examining The Influence Of Source Dependence On Supplier Performance In The Usaf Organic Supply Chain, Thomas A. Counter
Theses and Dissertations
The purpose of this study is to examine the U.S. Air Force's dependence toward sole sourcing and how that influences procurement outcomes in terms of supplier performance. This research used linear regression to explain the effect of source dependence and supplier size on performance categories for 326 suppliers. The five supplier performance categories in the study included timeliness, cost control, quality, business relations, and regulatory compliance. The research found that the USAFs dependence on sole sourcing had a small but statistically significant influence on all five aspects of supplier performance, with timeliness being the most adversely impacted.
Statistically Defensible Wind Tunnel Models, Timothy A. Roche
Statistically Defensible Wind Tunnel Models, Timothy A. Roche
Theses and Dissertations
Wind tunnels are used to test scale-model air frames in order to collect aerodynamic data. The Subsonic Aerodynamic Research Laboratory (SARL) Wind Tunnel is a low speed wind tunnel located at Wright-Patterson Air Force Base. The SARL Wind Tunnel team approached AFIT for assistance in creating statistically defensible models for the conditions inside the wind tunnel. During a wind tunnel test, pressure sensors cannot be placed at the test model. Instead, pressure is measured by a pitot probe permanently mounted in the corner of the test chamber. The pressure at the model location is predicted from the measurements taken by …