Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Series

Discipline
Institution
Keyword
Publication Year
Publication
File Type

Articles 3391 - 3420 of 75019

Full-Text Articles in Engineering

Excitation And Polarization Of Isolated Neurons By High-Frequency Sine Waves For Temporal Interference Stimulation, Iurii Semenov, Vitalii Kim, Giedre Silkuniene, Andrei G. Pakhomov Jan 2025

Excitation And Polarization Of Isolated Neurons By High-Frequency Sine Waves For Temporal Interference Stimulation, Iurii Semenov, Vitalii Kim, Giedre Silkuniene, Andrei G. Pakhomov

Bioelectrics Publications

The capacity of temporal interference (TI) stimulation to target deep brain regions without affecting nearby surface electrodes remains uncertain. Using artifact-free optical recording, we compare excitation patterns and thresholds in hippocampal neurons stimulated by “pure” and amplitude-modulated sine waves, representing TI waveforms near electrodes and at the target, respectively. We show that pure 2- and 20-kHz sine waves induce repetitive firing at rates that increase up to 60–90 Hz with stronger electric fields. Beyond this limit, action potentials merge into sustained depolarization, resulting in an excitation block. Modulating the sine waves at 20 Hz aligns firing with amplitude “beats” and …


A Time-Domain Boundary Integral Equation For Moving Acoustic Sources In Uniform Flow And Its Solution By An Advanced Time Propagation Approach, Fang Q. Hu, Douglas M. Nark Jan 2025

A Time-Domain Boundary Integral Equation For Moving Acoustic Sources In Uniform Flow And Its Solution By An Advanced Time Propagation Approach, Fang Q. Hu, Douglas M. Nark

Mathematics & Statistics Faculty Publications

This paper presents a time-domain boundary integral equation (TDBIE) formulation for predicting acoustic scattering from moving sources in a uniform mean flow. This work is motivated by the increasing need for accurate aeroacoustic modeling of modern aircraft configurations, including VTOL and eVTOL systems with rotating components. A key challenge in time-domain scattering simulations with moving sources is the determination of retarded time for a given observer time, which involves solving an implicit equation at each time step. This can be computationally costly, particularly for numerical solution of the TDBIE where every surface element on the scattering body acts as an …


Cryogenic Gas Cell For Infrared Space Instrumentation, Trent Newswander, Scott Bailey, Mark Hervig, Phillip Scott, Ryan Luder, Mike Watson, Mike Oksness, Cody Secrist, Zack Hatfield Jan 2025

Cryogenic Gas Cell For Infrared Space Instrumentation, Trent Newswander, Scott Bailey, Mark Hervig, Phillip Scott, Ryan Luder, Mike Watson, Mike Oksness, Cody Secrist, Zack Hatfield

Space Dynamics Laboratory Publications

• NASA’s Dynamical Neutral Atmosphere-Ionosphere Coupling (DYNAMIC) mission aims to characterize the energy transfer between the ionosphere, thermosphere, and mesosphere

– Identified as a high priority solar terrestrial probe mission in two decadal surveys

– Led by Virginia Polytechnic Institute and State University

• The Doppler Wind and Temperature Sounder (DWTS) is being developed for flight on the DYNAMIC satellite

– Will provide the first comprehensive global dataset of winds and temperature in the mesosphere and thermosphere (40–250 km altitude)

– Designed and built by Space Dynamics Lab (SDL)

• DWTS observes the Doppler shift of atmospheric NO and 13 …


Design And Characterization Of The Icon Fuv Ccd Cameras, Erik Syrstad, Brian Thompson, Robert Burt, Mitch Whiteley, James Champagne, Pedro Sevilla Jan 2025

Design And Characterization Of The Icon Fuv Ccd Cameras, Erik Syrstad, Brian Thompson, Robert Burt, Mitch Whiteley, James Champagne, Pedro Sevilla

Space Dynamics Laboratory Publications

Outline

  • FUV Overview
  • Key Requirements
  • Camera Design
  • Assembly and Integration
  • UV Performance Characterization


Atms And Cris Geolocation, Mark Esplin, Kris Robinson, Ben Esplin, Nephi Grant, Deron Scott, Likun Wang Jan 2025

Atms And Cris Geolocation, Mark Esplin, Kris Robinson, Ben Esplin, Nephi Grant, Deron Scott, Likun Wang

Space Dynamics Laboratory Publications

Contents

  • Summary of Suomi NPP sensors CrIS, ATMS, and VIIRS 
  • Geolocation methods 
  • Software optimization
  • CrIS geolocation results
  • ATMS geolocation results
  • Conclusions


Comparison Of Co-Located Mid-Latitude Sporadic E And Simone Wind Observations, Ivana Molina, Kenneth Obenberger, Jorge Chau, Matthias Clahsen Jan 2025

Comparison Of Co-Located Mid-Latitude Sporadic E And Simone Wind Observations, Ivana Molina, Kenneth Obenberger, Jorge Chau, Matthias Clahsen

Space Dynamics Laboratory Publications

Sporadic E are localized layers of enhanced metallic ionization that form in the E region of the ionosphere (Mathews, 1998). They are usually observed between 95 and 120 km altitude with a thickness in altitude ranging from ~100 m to a few kilometers. Studying these layers is important, as their characteristics and variability impact the propagation of HF radio waves. At mid-latitudes, the generation of sporadic E is most often explained by the wind shear theory, where these layers form due to the convergence of ions generated by vertical shears in the horizontal components of the neutral wind. The primary …


Reset Reengineering, System Engineering & Test Services, David Brenchley, Matt Dayley, Al Dubovik Jan 2025

Reset Reengineering, System Engineering & Test Services, David Brenchley, Matt Dayley, Al Dubovik

Space Dynamics Laboratory Publications

Sustainment of aging Department of Defense systems presents significant challenges. The Space Dynamics Laboratory (SDL) offers a cost-effective partnership to help the military maintain or enhance the capability of legacy systems. SDL provides trusted reengineering, system engineering, and test (RESET) services, providing Government-owned technical solutions that help the military:


Calibration And Systems Engineering Collaboration, John Wilson Jan 2025

Calibration And Systems Engineering Collaboration, John Wilson

Space Dynamics Laboratory Publications

Systems engineering and calibration engineering are critical to the efficient development, production, and operation of complex systems. Systems engineering provides the framework for the system lifecycle, ensuring stakeholder needs are met through integrated solutions. Calibration engineering ensures the accuracy, reliability, traceability of measurement, and compliance with standards. Coordination between system engineering and calibration ensures that instrumentation, control systems, and system performance are enabled. As the lifecycle coordinator, systems engineering relies on calibration engineers to reduce risks, optimize development, and ensure operational success.

However, the relationship between these disciplines is often poorly coordinated, as noted in tabletop discussions at CalCon 2024. …


Laser-Induced Graphene For Early Disease Detection: A Review, Sri Ramulu Torati, Gymama Slaughter Jan 2025

Laser-Induced Graphene For Early Disease Detection: A Review, Sri Ramulu Torati, Gymama Slaughter

Center for Bioelectronics Publications

Electrochemical biosensors have been instrumental in early disease detection, facilitating effective monitoring and treatment. The emergence of graphene has significantly advanced sensor technology in various fields, including biomedicine, electronics, and energy. In this landscape, laser‐induced graphene (LIG) has emerged as a superior alternative to conventional graphene synthesis methods. Its straightforward fabrication process and compatibility with wearable devices boost its practicality and potential for real‐world applications. This review highlights the transformative potential of LIG in biosensing, showcasing its contributions to the development of next‐generation diagnostic tools for early disease detection. An overview of the LIG synthesis process and its applications in …


Passive Thermal Control Technologies: Short Course, Holly Mortensen, Matt Ralphs Jan 2025

Passive Thermal Control Technologies: Short Course, Holly Mortensen, Matt Ralphs

Space Dynamics Laboratory Publications

  • Introduction to Space Dynamics Laboratory
  • Overview - Thermal Control Technologies
  • Conductor Bars
  • Thermal Straps
  • Break
  • Radiators
  • Thermal Switches


Phase Change Cells, T. Shane Topham, Gail Bingham, Harry Latvakoski, Mike Watson Jan 2025

Phase Change Cells, T. Shane Topham, Gail Bingham, Harry Latvakoski, Mike Watson

Space Dynamics Laboratory Publications

Outline

  • Phase Change Cell Introduction
  • Summary of ISS Phase Change Cell Experiments
  • Ground Cell Design Improvements and Test Results


Space Dynamics Laboratory, Brent Carlsen, Doug Jewell Jan 2025

Space Dynamics Laboratory, Brent Carlsen, Doug Jewell

Space Dynamics Laboratory Publications

  • Space Dynamics Laboratory
  • SDL is a UARC
  • RE-SET (Re-Engineering, System Engineering & Test)
  • System Test Development


Deriving Nonlinearity Coefficients From Changing Background, Mark Esplin, Deron Scott, Bryce Walker, Ben Esplin Jan 2025

Deriving Nonlinearity Coefficients From Changing Background, Mark Esplin, Deron Scott, Bryce Walker, Ben Esplin

Space Dynamics Laboratory Publications

Contents

  • Quadric Nonlinearity
  • Nonlinearity Model and Sensitivity Studies
  • Application to CrIS Sensor
  • Check Method with Stepped Blackbody Data
  • Conclusions


Guidelines For Radiometric Calibration Of Electro-Optical Instruments For Remote Sensing, Utah State University Space Dynamics Laboratory Jan 2025

Guidelines For Radiometric Calibration Of Electro-Optical Instruments For Remote Sensing, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL Presentation on Radiometric Calibration of Electro-Optical Instruments for Remote Sensing


Reducing Friction In Machine Oil Via Cesium-Hybridized Graphene Oxide Quantum Dot Additives, Islam Gomaa, Sherief Elsoudy, Maryam Galal, Ahmed Azim Jan 2025

Reducing Friction In Machine Oil Via Cesium-Hybridized Graphene Oxide Quantum Dot Additives, Islam Gomaa, Sherief Elsoudy, Maryam Galal, Ahmed Azim

Nanotechnology Research Centre

Friction and wear are among the most common causes of energy loss and component failure in mechanical systems, accounting for around 20–30% of total global energy consumption. Conventional lubricants fail to provide consistent performance in harsh conditions due to inadequate additive dispersion, agglomeration, and restricted surface reactivity. Recent advances in nanomaterial-based lubricants have shown promise, but it remains difficult to achieve significant friction and wear reduction at low additive concentrations while preserving stability. In this study, we synthesized and tested cesium-hybridized graphene oxide quantum dots (Cs-GOQDs) as novel lubricant additives. When incorporated into machine oil at 0.1 wt%, Cs-GOQDs reduced …


Cultural Society Branding, Gabriella Nieves, Katie Parrish Jan 2025

Cultural Society Branding, Gabriella Nieves, Katie Parrish

Student Research Design & Innovation Symposium

Cultural Society is a non-profit organization dedicated to inspiring curiosity, improving education, and embracing diversity in our community. The presenters were tasked with creating a new brand identity for Cultural Society, as well as for its AAPI (Asian American and Pacific Islander) History Museum, where people can learn about AAPI history, cultures, and impacts in Rhode Island. The branding was developed in a way that represents Cultural Society's values of creativity, personal action, learning without borders, personal growth, and resilience. Shortly after graduation, one presenter was hired part-time by Cultural Society to design environmental graphics and promotional items for the …


Stowable Communication Board For Wheelchair Users, Andrew Peet, Harrison Ullucci, Aaliyah Couto Jan 2025

Stowable Communication Board For Wheelchair Users, Andrew Peet, Harrison Ullucci, Aaliyah Couto

Student Research Design & Innovation Symposium

Communication boards are essential tools for individuals who use wheelchairs, experience speech limitations, are paraplegic, or quadriplegic. These simple and affordable devices enable them to effectively express their needs and interact with their environment. Traditional communication boards often present accessibility challenges due to restrictive placement and ergonomic constraints. This prototype integrates a motorized folding mechanism, so the board can be stowed when not in use and includes a selection of boards that can be swapped out. It is designed to enhance the usability and accessibility of communication boards while maintaining the width and mobility of the wheelchair. The prototype incorporates …


Metallic Nanoparticles And Cosmetics: The Role Of Mitochondria And Premature Aging, Veronica Montesinos-Cruz, Justin Olmanson Jan 2025

Metallic Nanoparticles And Cosmetics: The Role Of Mitochondria And Premature Aging, Veronica Montesinos-Cruz, Justin Olmanson

Department of Teaching, Learning, and Teacher Education: Faculty Publications

The cosmetic industry has developed and commercialized numerous products using new technologies, making them increasingly appealing to the public. The use of metallic nanoparticles (MtNPs) as key ingredients in cosmetics has become more widespread due to their demonstrated benefits. However, the use of these products remains controversial, as some studies have shown that MtNPs can penetrate the deeper layers of the skin and disrupt homeostatic balance. It has also been demonstrated that the interaction between MtNPs and keratinocytes increases the generation of reactive oxygen species (ROS), which can lead to oxidative stress, a condition associated with premature aging. Mitochondria, as …


Sharing The Stage With The Future: Humans And Robots Together At Last, Donna L. Clevinger Jan 2025

Sharing The Stage With The Future: Humans And Robots Together At Last, Donna L. Clevinger

Honors in Practice Online Archive

This essay presents a co-curricular collaboration bringing ancient comedy to a modern audience. Students and faculty at a large, public R1 university combine art and engineering to create a STEAM-based approach to theatrical production. The author describes how integrating classical text, creative expression, and transformational technologies demonstrates that collaboration between disciplines can produce gains for each, fostering advancements and human understanding that would be unattainable independently. Script writing, casting, stage production, and outcomes are presented.


Mapping Pilot Stress And Fatigue During Flight Sessions, Atandrila Chowdhury, Sudip Vhaduri, Julius Keller, Mark Wilson, Debra Henneberry Jan 2025

Mapping Pilot Stress And Fatigue During Flight Sessions, Atandrila Chowdhury, Sudip Vhaduri, Julius Keller, Mark Wilson, Debra Henneberry

Discovery Undergraduate Interdisciplinary Research Internship

This study examined physiological and self-reported indicators of stress and fatigue in four student pilots during training flights at Purdue University. Each pilot wore a wrist sensor that recorded heart rate, electrodermal activity, temperature, and acceleration, and completed pre and post-flight ratings of stress, fatigue, and sleep questionnaire. The pilots flew different types of training sessions, providing variation in environmental and flight conditions. All physiological data were cleaned and standardized before analysis. Across pilots, temperature and electrodermal activity generally increased during flight, showing a gradual rise in arousal that can come from several factors, including heat, physical effort, and normal …


Charting A Path For Writing In Aviation: The Intersection Of Wac And Collegiate Flight Training, Kayla D. Taylor, Lindsey Ives Jan 2025

Charting A Path For Writing In Aviation: The Intersection Of Wac And Collegiate Flight Training, Kayla D. Taylor, Lindsey Ives

Graduate Student Works

Understanding how genre conventions shape written communication within collegiate flight programs is an emerging area of WAC research. Collegiate flight students, who will enter the aviation industry in a variety of roles, must be able to write in various genres, including incident and accident reports, in ways that allow a range of readers to partake in a proactive safety culture. This study explored how supplemental discipline-specific guidance affected the writing quality of incident report narratives composed by students at a flight school within an accredited university in the United States. Participants were either given no guidance, bullet-point guidelines, or examples …


Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat Jan 2025

Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage …


Active Phytoextraction Of Toluene Shifts The Microbiome And Enhances Degradation Capacity In Hybrid Poplar, Michael Benisrael, Dasiel Obregon, Philipp Wanner, Jeremy Fernandes, Joel G. Burken, Ramon Aravena, Beth L. Parker, Elizabeth A. Haack, David T. Tsao, Kari E. Dunfield Jan 2025

Active Phytoextraction Of Toluene Shifts The Microbiome And Enhances Degradation Capacity In Hybrid Poplar, Michael Benisrael, Dasiel Obregon, Philipp Wanner, Jeremy Fernandes, Joel G. Burken, Ramon Aravena, Beth L. Parker, Elizabeth A. Haack, David T. Tsao, Kari E. Dunfield

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hybrid poplars are widely recognized for their effectiveness in remediating subsurface aromatic hydrocarbon contaminants, including benzene, toluene, ethylbenzene, and xylene isomers (BTEX). While BTEX compounds are frequently found in the transpiration streams of poplars at contaminated sites, the microbial dynamics within these trees, particularly in response to hydrocarbon exposure, remain underexplored. This study utilized high-throughput amplicon sequencing to investigate the trunk microbiome in hybrid poplars at a field-scale toluene phytoremediation site. Across the plant growth season (spring to late summer), we observed a significant seasonal increase in bacterial diversity and richness, particularly in trees located in areas with the highest …


Innovative Air Convection Embankment For Cold/Arctic Region Low-Volume Roads, Hanli Wu, Jenny Liu, Xiong Zhang, Steve Saboundjian Jan 2025

Innovative Air Convection Embankment For Cold/Arctic Region Low-Volume Roads, Hanli Wu, Jenny Liu, Xiong Zhang, Steve Saboundjian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Roadbed thaw settlement is a unique challenge for the durability of low-volume roads (LVRs) in permafrost regions. Air convection embankment (ACE) is an effective technique that acts as a semi-heat-transfer system to control temperature variation and reduce the thaw depth of subsoil. However, limited by the shortage of the necessary crushed rocks within a short distance, building an ACE in Alaska, U.S., is prohibitively expensive. Previous studies identified the feasibility of using cellular concrete for ACE and determined the optimized thickness of the cellular concrete aggregate interlayer for ACE. However, the economic efficiency and thermal and mechanical performance of the …


Nobocap: Unlocking Mdr/Ivdr Regulations For Innovators In Europe, Graham Gavin, Claire Brougham Jan 2025

Nobocap: Unlocking Mdr/Ivdr Regulations For Innovators In Europe, Graham Gavin, Claire Brougham

Conference Papers

The NoBoCap project (nobocap.eu) is aimed at addressing some of the challenges encountered by both SMEs and Notified Bodies across the EU. It is a multi-organizational consortium including universities, a Notified Body, and Bio-health and Innovation Hubs and Clusters. The NoBoCap project has several work packages focussed on:• Design and delivery of funded short-term courses.• Creating a dedicated NB job board.• Design and delivery of funded university accredited modules.• Design and development of e-tools to support manufacturers.• Develop a community platform to act as a voice for start-ups and SMEs


Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park Jan 2025

Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park

Engineering Management & Systems Engineering Faculty Publications

Traditionally, traffic incident management (TIM) programs coordinate the deployment of emergency resources to immediate incident requests without accommodating the interdependencies on incident evolutions in the environment. However, ignoring these inherent interdependencies while making current deployment decisions is shortsighted, and the resulting naive deployment strategy can significantly worsen the overall incident delay impact on the network. The interdependencies on incident evolution in the environment, including those between incident occurrences and those between resource availability in near-future requests and the anticipated duration of the immediate incident request, should be considered through a look-ahead model when making current-stage deployment decisions. This study develops …


Integrating Data Management Plans Into The Unified Architecture Framework Standards Views, Cansu Yalim, Holly A. H. Handley Jan 2025

Integrating Data Management Plans Into The Unified Architecture Framework Standards Views, Cansu Yalim, Holly A. H. Handley

Engineering Management & Systems Engineering Faculty Publications

System Architecting translates an operational concept into a model of the system to be realized. There is a need for a Data Management Plan (DMP) to be included in the overall system engineering process with the advent of Digital Engineering. Data longevity, accessibility, and integrity can all be improved throughout the system's lifecycle by a well-defined DMP. System engineers use an architecture framework to arrange the system data into several sets of viewpoints. Incorporating a DMP at this point specifies the procedures for gathering, storing, retrieving, and maintaining data to ensure that all interested parties have access to current, correct …


U.S. Perspectives On Deconstruction And Reuse Of Structural Wood Products, Fiona A. O'Donnell, N. L. Post, J. J. Lesko, Amelia E. Landry , '26, Abigail R. Peters , '26, Zoe A. E. Sperduto , '26 Jan 2025

U.S. Perspectives On Deconstruction And Reuse Of Structural Wood Products, Fiona A. O'Donnell, N. L. Post, J. J. Lesko, Amelia E. Landry , '26, Abigail R. Peters , '26, Zoe A. E. Sperduto , '26

Engineering Faculty Works

This paper identifies barriers, challenges, and requirements to the widespread adoption of Design for Deconstruction and Reuse (DfDR) of wood and engineered wood products in the United States (U.S.) to increase circularity in the built environment. A series of interviews with industry representatives were performed to summarize the state-of-the-art related to DfDR and gain insight into the perspectives and attitudes of the primary stakeholders; the results of these interviews were compared to the current academic literature. Results indicate that further emphasis is needed on closing the loop through the reuse phase, which is limited by a lack of regulations and …


Sensorized Autonomous Manipulation Platform For Underwater Buoyancy Analysis And Redesign, Matthew Satriale Jan 2025

Sensorized Autonomous Manipulation Platform For Underwater Buoyancy Analysis And Redesign, Matthew Satriale

Engineering Theses

The Office of Naval Research (ONR) is collaborating with the University of Massachusetts Lowell, the Naval Underwater Research Center, and Brown University to research the uses of an unmanned underwater vehicle (UUV). Brown University has sub-contracted Roger Williams University to develop a sensorized test platform with varying task modules for the UUV to interact with. The platform will hang in a test pool and report task statuses in real time. The current design requires an additional five-pound weight for proper pool wall contact. This report describes the analysis done to redesign the platform with the goal of removing the additional …


Optimizing Indoor Localization Using Rssi And Iq Data With Machine Learning, Gokdeniz Tingur Jan 2025

Optimizing Indoor Localization Using Rssi And Iq Data With Machine Learning, Gokdeniz Tingur

Computer Science Theses

This paper explores implementing and evaluating a Bluetooth Low Energy (BLE)-based indoor localization system using Received Signal Strength Indicator (RSSI) and Angle of Arrival (AoA) data via machine learning. A survey of localization technologies (RFID, GPS, ZigBee, and BLE) provides context on capabilities and limitations in indoor positioning. IQ data and phase-based angle estimation show how BLE 5.1’s direction-finding features enable sub-meter accuracy. A multi-phase experiment in a three-story academic building examines model performance with different tag distributions, movement patterns, and environmental constraints. Machine learning models such as Support Vector Machines and Deep Neural Networks are trained and evaluated across …