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

Engineering Commons™

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

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 20281 - 20310 of 196403

Full-Text Articles in Engineering

02.05.2024 Orsp Connect, Liz Williamson Feb 2024

02.05.2024 Orsp Connect, Liz Williamson

ORED Newsletter

NSF Revises PAPPG, Mickey McLaurin spotlight, ORSP Training Available: NSF Project Summary, Inclusive Entrepreneurship Event


Two-Scale Data-Driven Design For Heat Manipulation, Daicong Da, Wei Chen Feb 2024

Two-Scale Data-Driven Design For Heat Manipulation, Daicong Da, Wei Chen

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Data-driven methods have gained increasing attention in computational mechanics and design. This study investigates a two-scale data-driven design for thermal metamaterials with various functionalities. To address the complexity of multiscale design, the design variables are chosen as the components of the homogenized thermal conductivity matrix originating from the lower scale unit cells. Multiple macroscopic functionalities including thermal cloak, thermal concentrator, thermal rotator/inverter, and their combinations, are achieved using the developed approach. Sensitivity analysis is performed to determine the effect of each design variable on the desired functionalities, which is then incorporated into topology optimization. Geometric extraction demonstrates an excellent matching …


Evolvement Of Excusable Delay Clauses In Government Contracts Since The Covid-19 Pandemic, Jung Hyun Lee, Yunping Liang, Seyed Mohammad Ehsan Tabatabaee, Bryce Riccitelli Feb 2024

Evolvement Of Excusable Delay Clauses In Government Contracts Since The Covid-19 Pandemic, Jung Hyun Lee, Yunping Liang, Seyed Mohammad Ehsan Tabatabaee, Bryce Riccitelli

Durham School of Architectural Engineering and Construction: Faculty Publications

Excusable delay clauses in government construction contracts, often considered boilerplate with minimal modifications, have increased in attention since the outbreak of COVID-19. Despite the studies enumerating triggering events of the clause in the background of the pandemic, it is necessary to capture insights into how the unprecedented event is systematically accommodated by contract languages. The overarching goal of this study is to identify changes in contract languages over the pre-and post-pandemic eras by state departments of transportation (DOTs), focusing on excusable delay clauses. This study conducts a content analysis and a comparative analysis of state DOT construction contract documents, including …


Droplet Jump From A Particle Bed, Karl Cardin, Facundo Cabrera-Booman, Raúl Bayoán Cal Feb 2024

Droplet Jump From A Particle Bed, Karl Cardin, Facundo Cabrera-Booman, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Drop tower experiments have been performed to study droplet jump from a particle bed across a wide range of fluid viscosities. Here the droplet jumps from the particle bed in response to the apparent step reduction from terrestrial gravity to microgravity when the experiment is dropped and enters free fall. The presence of a particle layer has been found to affect contact line dissipation and the overall jumping behavior of droplets. Additionally, the study has identified the impact of the Ohnesorge number (Oh) on droplet morphology. The investigation has yielded results that not only validate a modified version of the …


Inhibited Surface Diffusion In Nanoporous Multi-Principal Element Alloy Thin Films Prepared By Vacuum Thermal Dealloying, Tibra Das Gupta, Thomas John Balk Feb 2024

Inhibited Surface Diffusion In Nanoporous Multi-Principal Element Alloy Thin Films Prepared By Vacuum Thermal Dealloying, Tibra Das Gupta, Thomas John Balk

Chemical and Materials Engineering Faculty Publications

Nanoporous structures with 3D interconnected networks are traditionally made by dealloy- ing a binary precursor. Certain approaches for fabricating these materials have been applied to refrac- tory multi-principal element alloys (RMPEAs), which can be suitable candidates for high-temperature applications. In this study, nanoporous refractory multi-principal element alloys (np-RMPEAs) were fabricated from magnesium-based thin films (VMoNbTaMg) that had been prepared by magnetron sputtering. Vacuum thermal dealloying (VTD), which involves sublimation of a higher vapor pres- sure element, is a novel technique for synthesizing nanoporous refractory elements that are prone to oxidation. When VMoNbTaMg was heated under vacuum, a nanoporous structure was …


The Roles Of Carbonaceous Wastes For Catalysis, Energy, And Environmental Remediation, Chi Huey Ng, Mohd Aizzan Mistoh, Siow Hwa Teo, Andrea Galassi, Hin Taufiq-Yap, Nancy Julius Siambun, Jurry Foo, Coswald Stephen Sipaut, Jeffrey Seay, Jidon Janaun Feb 2024

The Roles Of Carbonaceous Wastes For Catalysis, Energy, And Environmental Remediation, Chi Huey Ng, Mohd Aizzan Mistoh, Siow Hwa Teo, Andrea Galassi, Hin Taufiq-Yap, Nancy Julius Siambun, Jurry Foo, Coswald Stephen Sipaut, Jeffrey Seay, Jidon Janaun

Chemical and Materials Engineering Faculty Publications

This article reviews recent studies about various generations of the carbon materials for their applications in energy and environmental remediation. The synthesis routes of the carbon materials including the condition parameters, interaction of precursors, dopants and carbon materials, as well as their physical/chemical properties are explicated first. Then, the application and mechanism of metal-free/metal-doped/non-metal-doped carbon materials are discussed in detail. Lastly, this review is ended with a summary and invigorating perspectives on the challenges and future directions at the forefront of the catalysis platform to take a step further for real application.


Characterizing Linearizable Qaps By The Level-1 Reformulation-Linearization Technique, Lucas Waddell, Warren Adams Feb 2024

Characterizing Linearizable Qaps By The Level-1 Reformulation-Linearization Technique, Lucas Waddell, Warren Adams

Faculty Journal Articles

The quadratic assignment problem (QAP) is an extremely challenging NP-hard combinatorial optimization program. Due to its difficulty, a research emphasis has been to identify special cases that are polynomially solvable. Included within this emphasis are instances which are linearizable; that is, which can be rewritten as a linear assignment problem having the property that the objective function value is preserved at all feasible solutions. Various known sufficient conditions for identifying linearizable instances have been explained in terms of the continuous relaxation of a weakened version of the level-1 reformulation-linearization-technique (RLT) form that does not enforce nonnegativity on a subset …


Investigating The Structure And Performance Of Electrodes Made By Dry And Wet Slurry Processes, Kubra Uzun, Bhamiti Sharma, Bradley R. Frieberg, Ming Wang, Jiazhi Hu, Anita Li, Xiaosong Huang, Yang-Tse Cheng Feb 2024

Investigating The Structure And Performance Of Electrodes Made By Dry And Wet Slurry Processes, Kubra Uzun, Bhamiti Sharma, Bradley R. Frieberg, Ming Wang, Jiazhi Hu, Anita Li, Xiaosong Huang, Yang-Tse Cheng

Chemical and Materials Engineering Faculty Publications

Performance, cost, and safety are vital factors in producing and handling lithium-ion batteries. Using a dry process reduces the cost and environmental impact of producing large-scale lithium-ion battery electrodes significantly as solvents are eliminated. Thus, in this study, solvent-free dry electrostatic spray deposition (ESD) and conventional slurry processes were compared to uncover the influence of the manufacturing process on thick LiNi 0.8Mn0.1Co 0.1O 2 (NMC 811) positive electrodes. More pressure during calendering was found necessary for the dry-made (dry) electrodes to have the same porosity, leading to more cracks within the NMC particles and better adhesion. At slower discharge rates, …


Construction Software: Use, Selection, And Performance In Low-Bid Contracting, David R. Cazares Feb 2024

Construction Software: Use, Selection, And Performance In Low-Bid Contracting, David R. Cazares

Construction Management

The qualitative research included in this study evaluates the use, selection, and perceived gaps of current construction software suits in low-bid contracting. In addition, the data aims to provide merit to the correlation between construction software use and company performance. The intended stakeholders of this study include entrepreneurs in software development and construction, along with researchers looking to gather knowledge pertaining to this niche industry. Through a Google Forms questionnaire distributed via email, participants provide insight on the current status quo. The study’s responses show clear trends in the types of software currently in use and the subsequent reasons for …


Mission-Driven Inverse Design Of Blended Wing Body Aircraft With Machine Learning, Rohan S. Sharma, Serhat Hosder Feb 2024

Mission-Driven Inverse Design Of Blended Wing Body Aircraft With Machine Learning, Rohan S. Sharma, Serhat Hosder

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The intent of this work was to investigate the feasibility of developing machine learning models for calculating values of airplane configuration design variables when provided time-series, mission-informed performance data. Shallow artificial neural networks were developed, trained, and tested using data pertaining to the blended wing body (BWB) class of aerospace vehicles. Configuration design parameters were varied using a Latin-hypercube sampling scheme. These data were used by a parametric-based BWB configuration generator to create unique BWBs. Performance for each configuration was obtained via a performance estimation tool. Training and testing of neural networks were conducted using a K-fold cross-validation scheme. A …


High Temperatures And Low Soil Moisture Synergistically Reduce Switchgrass Yields From Marginal Field Sites And Inhibit Fermentation, Sarvada Chipkar, Kevin Kahmark, Sven Bohm, Mir Zaman Hussain, Leela Joshi, Karleigh M. Krieg, Jacob Aguado, Jasmine Cassidy, Pablo Lozano, Kevin Garland, Andrea Senyk, Derek J. Debrauske, Elizabeth Whelan, Morgan Davies, Paul Urban, G. Philip Robertson, Trey K. Sato, Stephen K. Hamilton, Kurt D. Thelen, Rebecca Ong Feb 2024

High Temperatures And Low Soil Moisture Synergistically Reduce Switchgrass Yields From Marginal Field Sites And Inhibit Fermentation, Sarvada Chipkar, Kevin Kahmark, Sven Bohm, Mir Zaman Hussain, Leela Joshi, Karleigh M. Krieg, Jacob Aguado, Jasmine Cassidy, Pablo Lozano, Kevin Garland, Andrea Senyk, Derek J. Debrauske, Elizabeth Whelan, Morgan Davies, Paul Urban, G. Philip Robertson, Trey K. Sato, Stephen K. Hamilton, Kurt D. Thelen, Rebecca Ong

Michigan Tech Publications

‘Marginal lands’ are low productivity sites abandoned from agriculture for reasons such as low or high soil water content, challenging topography, or nutrient deficiency. To avoid competition with crop production, cellulosic bioenergy crops have been proposed for cultivation on marginal lands, however on these sites they may be more strongly affected by environmental stresses such as low soil water content. In this study we used rainout shelters to induce low soil moisture on marginal lands and determine the effect of soil water stress on switchgrass growth and the subsequent production of bioethanol. Five marginal land sites that span a latitudinal …


Experimental Investigation Of A Heat Pump Tumble Dryer With A Zeotropic Refrigerant Mixture, Melanie Cop, Riley Barta, Christiane Thomas, Ulrich Hesse Feb 2024

Experimental Investigation Of A Heat Pump Tumble Dryer With A Zeotropic Refrigerant Mixture, Melanie Cop, Riley Barta, Christiane Thomas, Ulrich Hesse

School of Mechanical Engineering Faculty Publications

Due to their high global warming potential (GWP), fluorinated refrigerants are being replaced in many heat pump and refrigeration systems. Especially in small systems such as heat pump tumble dryers (HPTD), the replacement of the globally used working fluid in this application, R134a, appears to be manageable. One established alternative is the use of hydrocarbon refrigerants. Within this research project, new zeotropic refrigerant blends of hydrocarbons are theoretically evaluated as retrofit substitutes for R134a in heat pump tumble dryers. The aim is to use the temperature glide inherent to zeotropic mixtures during phase change to increase the heat transfer efficiency …


Containerization Of Seafarers In The International Shipping Industry: Contemporary Seamanship, Maritime Social Infrastructures, And Mobility Politics Of Global Logistics, Liang Wu Feb 2024

Containerization Of Seafarers In The International Shipping Industry: Contemporary Seamanship, Maritime Social Infrastructures, And Mobility Politics Of Global Logistics, Liang Wu

Dissertations, Theses, and Capstone Projects

This dissertation discusses the mobility politics of container shipping and argues that technological development, political-economic order, and social infrastructure co-produce one another. Containerization, the use of standardized containers to carry cargo across modes of transportation that is said to have revolutionized and globalized international trade since the late 1950s, has served to expand and extend the power of international coalitions of states and corporations to control the movements of commodities (shipments) and labor (seafarers). The advent and development of containerization was driven by a sociotechnical imaginary and international social contract of seamless shipping and cargo flows. In practice, this liberal, …


Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave Feb 2024

Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave

Dissertations, Theses, and Capstone Projects

The challenge of establishing a sustainable and circular economy for materials in medicine and technology necessitates bioinspired design. Nature's intricate machinery, forged through evolution, relies on a finite set of biomolecular building blocks with through-bond and through-space interactions. Repurposing these molecular building blocks requires a seamless integration of computational modeling, design, and experimental validation. The tools and concepts developed in this thesis pioneer new directions in peptide-materials design, grounded in fundamental principles of physical chemistry. We present a synergistic approach that integrates experimental designs and computational methods, specifically molecular dynamics simulations, to gain in-depth molecular insights crucial for advancing the …


Biomolecular Crystals As Functional Materials, Fahmeed Khan Sheehan Feb 2024

Biomolecular Crystals As Functional Materials, Fahmeed Khan Sheehan

Dissertations, Theses, and Capstone Projects

The field of supramolecular chemistry has undergone significant evolution over the last few decades, progressing from fundamental studies of self-assembling systems to the rational design of functional materials with exceptional properties. Among these materials, short peptides have emerged as a chemically simple yet highly versatile class of biomimetic compounds. Initially, short peptides were used as model systems to understand larger protein interactions. As the field progressed, short peptides were found to have exceptional functionality, and are now explored as functional nanomaterials for diverse applications. In many cases, short peptide materials have displayed properties not found in biology, in some cases …


Multi-Perspective Analysis For Derivative Financial Product Prediction With Stacked Recurrent Neural Networks, Natural Language Processing And Large Language Model, Ethan Lo Feb 2024

Multi-Perspective Analysis For Derivative Financial Product Prediction With Stacked Recurrent Neural Networks, Natural Language Processing And Large Language Model, Ethan Lo

Dissertations, Theses, and Capstone Projects

This study developed a multi-perspective, AI-powered model for predicting E-Mini S&P 500 Index Futures prices, tackling the challenging market dynamics of these derivative financial instruments. Leveraging FinBERT for analysis of Wall Street Journal data alongside technical indicators, trader positioning, and economic factors, my stacked recurrent neural network built with LSTMs and GRUs achieves significantly improved accuracy compared to single sub-models. Furthermore, ChatGPT generation of human-readable analysis reports demonstrates the feasibility of using large language models in financial analysis. This research pioneers the use of stacked RNNs and LLMs for multi-perspective financial analysis, offering a novel blueprint for automated prediction and …


Mathematical Model Of Oxygen, Nutrient, And Drug Transport In Tuberculosis Granulomas, Meenal Datta, Mccarthy Kennedy, Saeed Siri, Laura Via, James W. Baish, Lei Xu, Veronique Dartois, Clifton Barry, Rakesh Jain Feb 2024

Mathematical Model Of Oxygen, Nutrient, And Drug Transport In Tuberculosis Granulomas, Meenal Datta, Mccarthy Kennedy, Saeed Siri, Laura Via, James W. Baish, Lei Xu, Veronique Dartois, Clifton Barry, Rakesh Jain

Faculty Journal Articles

Physiological abnormalities in pulmonary granulomas–pathological hallmarks of tuberculosis (TB)–compromise the transport of oxygen, nutrients, and drugs. In prior studies, we demonstrated mathematically and experimentally that hypoxia and necrosis emerge in the granuloma microenvironment (GME) as a direct result of limited oxygen availability. Building on our initial model of avascular oxygen diffusion, here we explore additional aspects of oxy- gen transport, including the roles of granuloma vasculature, transcapillary transport, plasma dilution, and interstitial convection, followed by cellular metabolism. Approximate analytical solutions are provided for oxygen and glucose concentration, interstitial fluid velocity, interstitial fluid pressure, and the thickness of the convective zone. …


Generalized Linear Targeting For Cislunar Flight, David Geller, Brayden Barton, David Woffinden Feb 2024

Generalized Linear Targeting For Cislunar Flight, David Geller, Brayden Barton, David Woffinden

Space Dynamics Laboratory Publications

An important element of Artemis and NASA’s campaign to explore the Moon is the autonomous onboard two-level targeter (TLT) used during all cislunar flight phases. The function of the TLT is to autonomously recompute the burn targets for the upcoming burn (or multiple burns) in response to navigation and vehicle dispersion providing a solution that meets all trajectory constraints. Although the TLT has been utilized previously as a ground-based planning tool, and flown onboard during the Artemis I mission, it’s complexity and iterative nature make is difficult to incorporate into and support rapid analyses such as robust optimal trajectory design …


Glop: Learning Global Partition And Local Construction For Solving Large-Scale Routing Problems In Real-Time, Haoran Ye, Jiarui Wang, Helan Liang, Zhiguang Cao, Yong Li, Fanzhang Li Feb 2024

Glop: Learning Global Partition And Local Construction For Solving Large-Scale Routing Problems In Real-Time, Haoran Ye, Jiarui Wang, Helan Liang, Zhiguang Cao, Yong Li, Fanzhang Li

Research Collection School Of Computing and Information Systems

The recent end-to-end neural solvers have shown promise for small-scale routing problems but suffered from limited real-time scaling-up performance. This paper proposes GLOP (Global and Local Optimization Policies), a unified hierarchical framework that efficiently scales toward large-scale routing problems. GLOP partitions large routing problems into Travelling Salesman Problems (TSPs) and TSPs into Shortest Hamiltonian Path Problems. For the first time, we hybridize non-autoregressive neural heuristics for coarse-grained problem partitions and autoregressive neural heuristics for fine-grained route constructions, leveraging the scalability of the former and the meticulousness of the latter. Experimental results show that GLOP achieves competitive and state-of-the-art real-time performance …


Semantic Segmentation Of Longitudinal Thermal Images For Identification Of Hot And Cool Spots In Urban Areas, Vasantha Ramani, Pandarasamy Arjunan, Kameshwar Poolla, Clayton Miller Feb 2024

Semantic Segmentation Of Longitudinal Thermal Images For Identification Of Hot And Cool Spots In Urban Areas, Vasantha Ramani, Pandarasamy Arjunan, Kameshwar Poolla, Clayton Miller

Research Collection College of Integrative Studies

This work presents the analysis of semantically segmented, longitudinally, and spatially rich thermal images collected at the neighborhood scale to identify hot and cool spots in urban areas. An infrared observatory was operated over a few months to collect thermal images of different types of buildings on the educational campus of the National University of Singapore. A subset of the thermal image dataset was used to train state-of-the-art deep learning models to segment various urban features such as buildings, vegetation, sky, and roads. It was observed that the U-Net segmentation model with ‘resnet34’ CNN backbone has the highest mIoU score …


Fibrous Finite Element Modeling Of The Optic Nerve Head Region, Mohammad R. Islam, Fengting Ji, Manik Bansal, Yi Hua, Ian A. Sigal Feb 2024

Fibrous Finite Element Modeling Of The Optic Nerve Head Region, Mohammad R. Islam, Fengting Ji, Manik Bansal, Yi Hua, Ian A. Sigal

Mechanical Engineering Faculty Publications

The optic nerve head (ONH) region at the posterior pole of the eye is supported by a fibrous structure of collagen fiber bundles. Discerning how the fibrous structure determines the region biomechanics is crucial to understand normal physiology, and the roles of biomechanics on vision loss. The fiber bundles within the ONH structure exhibit complex three-dimensional (3D) organization and continuity across the various tissue components. Computational models of the ONH, however, usually represent collagen fibers in a homogenized fashion without accounting for their continuity across tissues, fibers interacting with each other and other fiber-specific effects in a fibrous structure. We …


Computational Modelling Of A Triaxial Vibrating Sample Magnetometer, Leo Rodriguez, Arjun Sapkota, Jonathan Alvarado, Jitendra S. Tate, Wilhelmus J. Geerts Feb 2024

Computational Modelling Of A Triaxial Vibrating Sample Magnetometer, Leo Rodriguez, Arjun Sapkota, Jonathan Alvarado, Jitendra S. Tate, Wilhelmus J. Geerts

Mechanical Engineering Faculty Publications

Magnetic Field Assisted Additive Manufacturing (MFAAM) enables 3D printing of magnetic materials of various shapes which exhibit a complex anisotropy energy surface containing contributions generated from different origins such as sample, particle, and agglomerate shape anisotropy, flow and field induced anisotropy, and particle crystal anisotropy. These novel magnet shapes require the need to measure the x, y, and z components of the magnetic dipole moment simultaneously to fully understand the magnetic reversal mechanism and unravel the complex magnetic anisotropy energy surface of 3D printed magnetic composites. This work aims to develop a triaxial vibrating sample magnetometer (VSM) by adding a …


Nanoparticles For Applications In Specific Diagnostics And Precision Medicine, Naxhije Berisha Feb 2024

Nanoparticles For Applications In Specific Diagnostics And Precision Medicine, Naxhije Berisha

Dissertations, Theses, and Capstone Projects

Heterogeneity is common in the expression of cancer and treatment response. Precision medicine enables healthcare providers to tailor medical care to an individual's distinct genetic and environmental makeup. This customization has the potential to result in more efficient treatments while minimizing side effects. We believe that by studying the interface of nanotechnology and cancer medicine we can elucidate innovative solutions that address the challenges of disease heterogeneity. This includes advancements in drug delivery, formulations development, and diagnostic sensing. We highlight three studies that use nanotechnology for applications in precision medicine. In Chapter 2, we highlight design optimization of drug formulations …


Beneath I-280: Excavating A Neighborhood Lost To San José Freeways, Leila Ullmann, Gordon Douglas Feb 2024

Beneath I-280: Excavating A Neighborhood Lost To San José Freeways, Leila Ullmann, Gordon Douglas

Mineta Transportation Institute

Throughout the 1960s and 1970s, thousands of people in San José, California were displaced from their homes as the state used eminent domain to purchase land and uproot neighborhoods for the construction of Interstate freeways. This report presents a multifaceted research and public knowledge effort that uncovers some of the communities buried beneath these freeways, in the area where I-280 and CA-87 meet today near downtown San José. The project builds primarily from previously unprocessed California Department of Transportation (CalTrans) archival documents, which this project studies for the first time. The records are rich in detail about valuation and sale …


Dl-Drl: A Double-Level Deep Reinforcement Learning Approach For Large-Scale Task Scheduling Of Multi-Uav, Xiao Mao, Guohua Wu, Mingfeng Fan, Zhiguang Cao, Witold Pedrycz Feb 2024

Dl-Drl: A Double-Level Deep Reinforcement Learning Approach For Large-Scale Task Scheduling Of Multi-Uav, Xiao Mao, Guohua Wu, Mingfeng Fan, Zhiguang Cao, Witold Pedrycz

Research Collection School Of Computing and Information Systems

Exploiting unmanned aerial vehicles (UAVs) to execute tasks is gaining growing popularity recently. To address the underlying task scheduling problem, conventional exact and heuristic algorithms encounter challenges such as rapidly increasing computation time and heavy reliance on domain knowledge, particularly when dealing with large-scale problems. The deep reinforcement learning (DRL) based methods that learn useful patterns from massive data demonstrate notable advantages. However, their decision space will become prohibitively huge as the problem scales up, thus deteriorating the computation efficiency. To alleviate this issue, we propose a double-level deep reinforcement learning (DL-DRL) approach based on a divide and conquer framework …


Adaptive Inter-Vehicular Collaboration For Level 5 Autonomous Driving, Sumbal Malik Feb 2024

Adaptive Inter-Vehicular Collaboration For Level 5 Autonomous Driving, Sumbal Malik

Dissertations

The evolution of sensor technologies, mobile networks, and artificial intelligence has significantly expanded the horizons of various sectors, notably in autonomous driving. According to the World Health Organization, over 1.3 million people succumb to traffic accidents annually, predominantly due to human negligence. Complex urban environments, characterized by mixed traffic flow involving Human Driven Vehicles and Connected and Autonomous Vehicles, intricate traffic patterns, frequent lane changes, and slow speeds, face escalating challenges related to traffic accidents and congestion. These challenges lead to wasted time, increased fuel consumption, and heightened pollution emission levels. Hence, the development of a safe and robust version …


Residual Optical Absorption From Native Defects In Cdsip2 Crystals, Timothy D. Gustafson, Nancy C. Giles, Elizabeth M. Scherrer, Kevin T. Zawilski, Peter G. Schunemann, Kent L. Averett, Jonathan E. Slagle, Larry E. Halliburton Feb 2024

Residual Optical Absorption From Native Defects In Cdsip2 Crystals, Timothy D. Gustafson, Nancy C. Giles, Elizabeth M. Scherrer, Kevin T. Zawilski, Peter G. Schunemann, Kent L. Averett, Jonathan E. Slagle, Larry E. Halliburton

Faculty Publications

CdSiP2 crystals are used in optical parametric oscillators to produce tunable output in the mid-infrared. As expected, the performance of the OPOs is adversely affected by residual optical absorption from native defects that are unintentionally present in the crystals. Electron paramagnetic resonance (EPR) identifies these native defects. Singly ionized silicon vacancies (V-Si) are responsible for broad optical absorption bands peaking near 800, 1033, and 1907 nm. A fourth absorption band, peaking near 630 nm, does not involve silicon vacancies. Exposure to 1064 nm light when the temperature of the CdSiP2 crystal is near 80K converts …


Us Public Opinion About The Safety Of Gene Editing In The Agriculture And Medical Fields And The Amount Of Evidence Needed To Improve Opinions, Brandon R. Mcfadden, Joy N. Rumble, Kathryn A. Stofer, Kevin M. Folta Feb 2024

Us Public Opinion About The Safety Of Gene Editing In The Agriculture And Medical Fields And The Amount Of Evidence Needed To Improve Opinions, Brandon R. Mcfadden, Joy N. Rumble, Kathryn A. Stofer, Kevin M. Folta

Agricultural Economics and Agribusiness Faculty Publications and Presentations

Introduction: Implementation of gene editing in agriculture and medicine hinges on public acceptance. The objectives of this study were to explore U.S. public opinion about gene editing in agricultural and medical fields and to provide more insight into the relationship between opinions about the safety of gene editing and the potential impact of evidence to improve opinions about safety.

Methods: Data were from two samples of U.S. respondents: 1,442 respondents in 2021 and 3,125 respondents in 2022. Survey respondents provided their opinions about the safety of gene editing in the agricultural and medical fields and answered questions about the number …


Accelerating Neurotechnology Development Using An Agile Methodology, Anil Kumar Thota, Ranu Jung Feb 2024

Accelerating Neurotechnology Development Using An Agile Methodology, Anil Kumar Thota, Ranu Jung

Biomedical Engineering Faculty Publications and Presentations

Novel bioelectronic medical devices that target neural control of visceral organs (e.g., liver, gut, spleen) or inflammatory reflex pathways are innovative class III medical devices like implantable cardiac pacemakers that are lifesaving and life-sustaining medical devices. Bringing innovative neurotechnologies early into the market and the hands of treatment providers would benefit a large population of patients inflicted with autonomic and chronic immune disorders. Medical device manufacturers and software developers widely use the Waterfall methodology to implement design controls through verification and validation. In the Waterfall methodology, after identifying user needs, a functional unit is fabricated following the verification loop (design, …


Measurements Of The Effective Stress Coefficient For Elastic Moduli Of Sandstone In Quasi-Static Regime Using Semiconductor Strain Gauges, Vassily Mikhaltsevitch, Maxim Lebedev Feb 2024

Measurements Of The Effective Stress Coefficient For Elastic Moduli Of Sandstone In Quasi-Static Regime Using Semiconductor Strain Gauges, Vassily Mikhaltsevitch, Maxim Lebedev

Research outputs 2022 to 2026

Numerous experimental and theoretical studies undertaken to determine the effective stress coefficient for seismic velocities in rocks stem from the importance of this geomechanical parameter both for monitoring changes in rock saturation and pore pressure distribution in connection with reservoir production, and for overpressure prediction in reservoirs and formations from seismic data. The present work pursues a task to determine, in the framework of a low-frequency laboratory study, the dependence of the elastic moduli of n-decane-saturated sandstone on the relationship between pore and confining pressures. The study was conducted on a sandstone sample with high quartz and notable clay content …