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Articles 16141 - 16170 of 196020

Full-Text Articles in Engineering

Fault Detection And Location In Renewable-Fed Distribution Systems Using Low Voltage Sensors, Bushra Farhat Aug 2024

Fault Detection And Location In Renewable-Fed Distribution Systems Using Low Voltage Sensors, Bushra Farhat

All Theses

The penetration of Distributed Energy Resources (DERs) into the Electric Power System (EPS) is increasing. These (DERs) are mostly inverter-based resources (IBRs) that are integrated into (EPS) at the distribution level. Therefore, it has become necessary to leverage the integration of (IBRs) for both commercial and residential distribution systems through the deployment of Microgrid (MG). However, existing distribution systems that use fuses for sensing and isolating faults are not equipped to handle protection of microgrids where fault currents are fed from multiple sources and can flow downstream or upstream. Bulk of the protection schemes proposed in literature are heavily dependent …

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Reconfigurable Over-The-Air Chamber: Measuring Radio Frequency Device Performance, Benjamin T. Arnold Aug 2024

Reconfigurable Over-The-Air Chamber: Measuring Radio Frequency Device Performance, Benjamin T. Arnold

Theses and Dissertations

Over-the-air (OTA) testing is particularly useful in determining the performance of multi-antenna communication devices in real-world environments. Traditional OTA testing technologies include the reverberation chamber (RC) and the multi-probe anechoic chamber. More recently, the reconfigurable OTA chamber (ROTAC), which is a RC that has probes lining its chamber walls, has been proposed. These probes are either driven with a source, possibly combined with a channel emulator, or are terminated with a tunable impedance. Controlling the excitations and terminations on the probes can alter the fields within the chamber and thereby synthesize an antenna response at the device under test (DUT). …

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Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber Aug 2024

Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber

Engineering and Technology Management Faculty Publications and Presentations

In the digital and global economy, business leaders need more than just business and technology competencies; they also require empathy. However, there is a notable scarcity of research on empathy in Scrum for product development. This study aims to uncover critical insights into how leaders can foster empathy within virtual Scrum teams. Accordingly, this paper proposes five pivotal themes leaders can employ: Scrum fundamentals, meditation, self- and other-analysis, healthy interactions, and informal connections. These vital strategies offer actionable methods for leaders seeking to enhance empathy within their virtual Scrum teams.

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Strengthening Capacity In Industrial Revolution 4.0 (Ir 4.0): A Case Study On Training Product-Service Systems Between The Us And Vietnam, Man Hang Yip, Ana Sofia Castellanos Santarnaria, Julia J. Babcock Aug 2024

Strengthening Capacity In Industrial Revolution 4.0 (Ir 4.0): A Case Study On Training Product-Service Systems Between The Us And Vietnam, Man Hang Yip, Ana Sofia Castellanos Santarnaria, Julia J. Babcock

Engineering and Technology Management Faculty Publications and Presentations

This case study analyzes how value is created in the development process of a collaborative training product-service system (PSS) designed for provincial government officials in Vietnam. This initiative, part of the USAID Strengthening Provincial Capacity (USAID SPC) project, encapsulates a series of training solutions designed to empower officials with key skills in engineering and technology management, including the knowledge to improve global value chains, upgrade technology infrastructure and sustainable production models. A primary driver for the “four-day course delivery”, the PSS analyzed in this study, was to bolster economic competitiveness at the provincial level in the context of Industrial Revolution …

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Rheology Modification Of Flowable Mortar With Co2, Sean Monkman, Soo Duck Hwang, Kamal Khayat Aug 2024

Rheology Modification Of Flowable Mortar With Co2, Sean Monkman, Soo Duck Hwang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Rheological Properties of Mortar Samples with Different Additions of CO2 during Mixing Were Determined. Flowable Cement-Based Mortars at Three Different W/c (0.55, 0.45 and 0.35) Were Produced and the Effects of CO2 Gas Were Examined on the Fresh Properties of Slump Flow, Yield Stress and Plastic Viscosity. According to the Experimental Results, the Mortar Yield Stress and Plastic Viscosity Increased Faster over Time Than in a Reference System with the Increasing Addition of CO2 and Greater Effects Were Seen at the Lowest W/c of 0.35 Than at the Others. the Impact of the CO2 on …

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Accelerating The Circular Economy Transition: A Construction Value Chain-Structured Portfolio Of Strategies And Implementation Insights, Radwa Eissa, Islam H. El-Adaway Aug 2024

Accelerating The Circular Economy Transition: A Construction Value Chain-Structured Portfolio Of Strategies And Implementation Insights, Radwa Eissa, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Despite the Increasing Recognition of the Potential of Circular Economy (CE) Strategies, their Effective Application to Decarbonize the Construction Value Chain Faces Multiple Challenges. Ambiguity Surrounding CE, stemming from a Lack of Clarity on Actionable Strategies, is a Common Concern. Existing Studies Lack a Holistic Approach for Systematically Integrating CE Principles throughout the Construction Value Chain, resulting in a Scarcity of Information on How to Practically Adopt CE within Projects. This Research Aims to Accelerate CE Adoption by Creating a Value Chain-Structured Portfolio of CE Strategies and Analyzing the Implementation of Such Strategies in Actual Projects. to This End, a …

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Pinn-Chk: Physics-Informed Neural Network For High-Fidelity Prediction Of Early-Age Cement Hydration Kinetics, Md Asif Rahman, Tianjie Zhang, Yang Lu Aug 2024

Pinn-Chk: Physics-Informed Neural Network For High-Fidelity Prediction Of Early-Age Cement Hydration Kinetics, Md Asif Rahman, Tianjie Zhang, Yang Lu

Civil Engineering Faculty Publications and Presentations

Cement hydration kinetics, characterized by heat generation in early-age concrete, poses a modeling challenge. This work proposes a physics-informed neural network (PINN) named PINN-CHK designed for cement hydration kinetics, to predict early-age temperature rises in cement paste. PINN-CHK leverages data-driven solutions to craft a high-fidelity prediction model, encompassing material properties and maturity functions in cement hydration. Trained on heated cement paste data, it simultaneously fits experimental results and underlying physics, yielding a mesh-free simulation. Incorporating governing partial differential equations (PDEs), and initial and boundary conditions into its loss function, PINN-CHK architecture undergoes rigorous benchmark testing, demonstrating unparalleled predictive accuracy compared …

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Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer Aug 2024

Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. the purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. the automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …

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Engineering The Properties Of Magnesium Aluminate Spinel Through Solid State Solutions, Robin Conner Aug 2024

Engineering The Properties Of Magnesium Aluminate Spinel Through Solid State Solutions, Robin Conner

All Theses

Magnesium aluminate spinel solid state solutions were prepared via the coprecipitation method and calcined in air at 900 °C for 2 h. The manipulation of magnesium aluminate spinel’s microstructure through the formation of solid state solutions with zinc and gadolinium substituting for magnesium was investigated. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR FTIR) confirmed the formation of a single cubic crystalline phase. The luminescence properties were investigated by radioluminescence (RL) under X-ray excitation and thermoluminescence (TL) measurements. In the case of zinc, all concentrations of the solid state solutions showed similar luminescence with bands at …

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Genetically-Encoded Optical Barcodes For Single-Cell Analysis, Daniel Pritko Aug 2024

Genetically-Encoded Optical Barcodes For Single-Cell Analysis, Daniel Pritko

All Theses

Cell barcodes are capable of being used to answer many different biological questions. They have been used to track the lineage of cells to identifying the function of a gene. While there are multiple different methods to creating cell barcodes, they are limited in their scalability and application. In a previous publication we propose and computationally prove an optical single-cell barcoding method that bridges fast and scalable readouts with the benefits of genetic encoding. In this approach fluorescent proteins (fps) are combined to form fluorescent barcodes that can then be analyzed using a spectral flow cytometer. Here, we test the …

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Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy Aug 2024

Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy

Civil and Environmental Engineering Faculty Publications and Presentations

Evacuation behavior models estimated using post-disaster surveys are not adequate to predict real-time dynamic population response as a hurricane unfolds. With the emergence of ubiquitous technology and devices in recent times, social media data with its higher spatio-temporal coverage has become a potential alternative for understanding evacuation behaviour during hurricanes. However, these data are often associated with selection bias and population representativeness issues. To that extent, the current study proposes a novel data fusion algorithm to combine heterogeneous data sources from transportation systems and social media, in a unified framework to understand and predict real-time population response during hurricanes. Specifically, …

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Enhanced Optical And Infrared Activity Of Nanosphere Dimers Attributed To Dimer Geometry, D. Keith Roper, Jin-Woo Kim, Ricardo R. Romo, Joseph Batta-Mpouma Aug 2024

Enhanced Optical And Infrared Activity Of Nanosphere Dimers Attributed To Dimer Geometry, D. Keith Roper, Jin-Woo Kim, Ricardo R. Romo, Joseph Batta-Mpouma

Biological and Agricultural Engineering Faculty Publications and Presentations

Enhanced optical and infrared activity of subwavelength metal nanoparticles is key to their use in optoelectronics, spectroscopy, and sensing. The present work compared spectra of nanosphere dimers merged by centrifuging gold nanospheres with corresponding simulated nanoscale dimers. Geometric features of the nanosphere dimers were related to corresponding optical and near-infrared activity through simulation. Differences in optical and infrared activity of the nanosphere dimers were largely attributable to changes in the radius of the nanosphere and the radius of the conductive junction between merged nanospheres. The features observed in the experimental spectra were attributed to a select number of dimers exhibiting …

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Fatigue Performance Of 3d-Printed Poly-Lactic-Acid Bone Scaffolds With Triply Periodic Minimal Surface And Voronoi Pore Structures, Hamed Bakhtiari, Alireza Nouri, Majid Tolouei-Rad Aug 2024

Fatigue Performance Of 3d-Printed Poly-Lactic-Acid Bone Scaffolds With Triply Periodic Minimal Surface And Voronoi Pore Structures, Hamed Bakhtiari, Alireza Nouri, Majid Tolouei-Rad

Research outputs 2022 to 2026

Bone scaffolds serve a crucial role in tissue engineering, particularly in facilitating bone regeneration where natural repair is insufficient. Despite advancements in the fabrication of polymeric bone scaffolds, the challenge remains to optimize their mechanical resilience. Specifically, research on the fatigue behaviour of polymeric bone scaffolds is scarce. This study investigates the influence of pore architecture on the mechanical performance of poly-lactic-acid (PLA) scaffolds under quasi-static and cyclic compression. PLA scaffolds with a 60% porosity were fabricated using extrusion-based 3D printing in various designs: Gyroid, Lidinoid, Fischer–Koch, IWP, and Voronoi. Results demonstrated that Gyroid scaffolds had the highest compressive strength …

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In-Situ Micro-Ct Analysis Of Deformation Behavior In Sandwich-Structured Meta-Stable Beta Ti−35nb Alloy, Yu Jing Lui, Zi Lin Zhang, Jin Cheng Wang, Xiang Wu, Xiao Chun Liu, Wei Ying Huang, Lai Chang Zhang Aug 2024

In-Situ Micro-Ct Analysis Of Deformation Behavior In Sandwich-Structured Meta-Stable Beta Ti−35nb Alloy, Yu Jing Lui, Zi Lin Zhang, Jin Cheng Wang, Xiang Wu, Xiao Chun Liu, Wei Ying Huang, Lai Chang Zhang

Research outputs 2022 to 2026

Beta Ti−35Nb sandwich-structured composites with various reinforcing layers were designed and produced using additive manufacturing (AM) to achieve a balance between light weight and high strength. The impact of reinforcing layers on the compressive deformation behavior of porous composites was investigated through micro- computed tomography (Micro-CT) and finite element method (FEM) analyses. The results indicate that the addition of reinforcement layers to sandwich structures can significantly enhance the compressive yield strength and energy absorption capacity of porous metal structures; Micro-CT in-situ observation shows that the strain of the porous structure without the reinforcing layer is concentrated in the middle region, …

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Slurry Infiltrated Low-Quality Construction And Demolition Coarse Aggregate Waste In Concrete - A Sustainable Construction, Vishnu Vijayan, Sanjay Kumar Shukla, K. M. Mini Aug 2024

Slurry Infiltrated Low-Quality Construction And Demolition Coarse Aggregate Waste In Concrete - A Sustainable Construction, Vishnu Vijayan, Sanjay Kumar Shukla, K. M. Mini

Research outputs 2022 to 2026

Exponential growth in infrastructure projects, stimulated by emerging sophisticated technologies have been instrumental in the salutary proliferation of the construction sector, globally. An indubitable adversity of the rapid boom in the construction industry has been the rampant cumulative fallout of burgeoning waste during the demolition and construction phases of restoration. The current study explored the propriety of replacing natural coarse aggregate by low-quality recycled coarse aggregates (RCA) with varying proportions, along with silica fume (SF) and polypropylene (PP) fibers as admixtures, for the preparation of concrete. As the quality of RCA is determined by the history of its parent demolished …

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Dual Modification Of Reverse Osmosis Membranes With Nh2-Mil-125 And Functionalised Multiwalled Carbon Nanotubes For Enhanced Nanoplastic Removal, Javad Farahbakhsh, Mohadeseh Najafi, Mitra Golgoli, Seyedeh Zahra Haeri, Mehdi Khiadani, Amir Razmjou, Masoumeh Zargar Aug 2024

Dual Modification Of Reverse Osmosis Membranes With Nh2-Mil-125 And Functionalised Multiwalled Carbon Nanotubes For Enhanced Nanoplastic Removal, Javad Farahbakhsh, Mohadeseh Najafi, Mitra Golgoli, Seyedeh Zahra Haeri, Mehdi Khiadani, Amir Razmjou, Masoumeh Zargar

Research outputs 2022 to 2026

The present study describes a novel double-modified strategy for developing high-performance thin-film composite reverse osmosis (TFC-RO) membranes by incorporating titanium-based metal organic frameworks (NH2-MIL-125) and functionalised multiwalled carbon nanotubes (MWCNTs) into the support layer and selective layer, respectively. Initially, the support layer was subjected to successive modifications using NH2-MIL-125 mixed with polysulfone (PSF) in dimethylformamide DMF solution to investigate their impact on the performance and properties of the support layer and resultant TFC-RO membranes. Results indicated that the new structure of the modified support layer had significant influences on the developed TFC-RO membranes. Notably, the pristine PSF support exhibited a …

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Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy Aug 2024

Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy

Mineta Transportation Institute

Embankments have been widely used in the construction of transportation and flood defense infrastructure. Embankments constructed from clays experience a suite of weather-driven deterioration processes that lead to a progressive loss of hydromechanical performance, causing potentially severe and costly consequences. This study aimed to predict the time to failure of aging, deteriorating clay embankments supporting transportation infrastructure. A multi-phase numerical modeling approach was developed to replicate the long-term, weather-driven, hydromechanical behavior of clay embankments. This model simulated the behavior of a number of well-documented embankment failure case studies that had sufficient data to derive the necessary soil properties and climate …

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Towards Load-Bearing Biomedical Titanium-Based Alloys: From Essential Requirements To Future Developments, Yu-Wei Cui, Liqiang Wang, Lai-Chang Zhang Aug 2024

Towards Load-Bearing Biomedical Titanium-Based Alloys: From Essential Requirements To Future Developments, Yu-Wei Cui, Liqiang Wang, Lai-Chang Zhang

Research outputs 2022 to 2026

The use of biomedical metallic materials in research and clinical applications has been an important focus and a significant area of interest, primarily owing to their role in enhancing human health and extending human lifespan. This article, particularly on titanium-based alloys, explores exceptional properties that can address bone health issues amid the growing challenges posed by an aging population. Although stainless steel, magnesium-based alloys, cobalt-based alloys, and other metallic materials are commonly employed in medical applications, limitations such as toxic elements, high elastic modulus, and rapid degradation rates limit their widespread biomedical applications. Therefore, titanium-based alloys have emerged as top-performing …

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Recent Progress In Microencapsulation Technology And Its Applications In Petroleum Industry, Jingyi Zhu, Jiayu He, Jie Zhou, Zhaozhong Yang, Xiaogang Li, Ying Li, Zhenjiang You Aug 2024

Recent Progress In Microencapsulation Technology And Its Applications In Petroleum Industry, Jingyi Zhu, Jiayu He, Jie Zhou, Zhaozhong Yang, Xiaogang Li, Ying Li, Zhenjiang You

Research outputs 2022 to 2026

Oilfield chemicals play a pivotal role in optimizing the development of oil and gas resources. Emerging technologies for the controlled release of these chemicals have captured considerable interest among petroleum engineers. Microencapsulation, a method widely employed for controlled release in various industries such as biotechnology, pharmaceuticals, and agriculture, is gaining traction in the realm of oil and gas exploitation. This paper provides a comprehensive review of encapsulation technologies, including solvent evaporation, coacervation, and polymerization methods. Special emphasis is placed on recent advancements in the applications of microcapsules within the oil and gas sector. Given the profound impact of release behavior …

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Tellurium Enrichment In Copper Tailings: A Mineralogical And Processing Study, José L. Corchado-Albelo, Lana Alagha Aug 2024

Tellurium Enrichment In Copper Tailings: A Mineralogical And Processing Study, José L. Corchado-Albelo, Lana Alagha

Mining Engineering Faculty Research & Creative Works

As the global demand for tellurium (Te) increases, it is crucial to develop efficient recovery methods that consider existing supply streams. This research combines gravity separation and froth flotation processes to enhance the recovery of Te minerals from tailings produced during the beneficiation of copper porphyry ores. Prior to processing, a systematic and comprehensive characterization study of copper tailing (CT) samples was conducted to examine the deportment of Te minerals in different mineral phases and to understand their locking and liberation behavior. Characterization techniques included inductively coupled plasma mass spectrometry (ICP-MS) and TESCAN's integrated mineral analysis (TIMA). Copper tailing characterization …

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Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer Aug 2024

Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. The purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. The automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …

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Design And Development Of Uio-67-Coated Pim-1-Based Composites And Demonstration Of Their Detoxification Performance, Sukanta K. Mondal, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei Aug 2024

Design And Development Of Uio-67-Coated Pim-1-Based Composites And Demonstration Of Their Detoxification Performance, Sukanta K. Mondal, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Polymer-supported MOF composites have emerged as versatile candidates for various separation and catalytic applications. In this study, we demonstrate design and development of UiO-67-coated Ce(OH)4@PIM-1 composites via dip-coating, drop-casting, solid-phase coating, and supramolecular assembly, and assess their preparation-structure-performance relations. The catalytic performance of the composites was investigated through hydrolysis of dimethyl 4-nitrophenyl phosphate (DMNP), as a nerve agent simulant. The findings revealed that while dip-coating method was unable to achieve a thick and uniform coverage of the MOF layer on the Ce(OH)4@PIM-1, the supramolecular assembly gave rise to 16 wt.% MOF loading and the composite prepared …

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Examination And Improvement Of The Taguchi-Based Nanofluids Impact On Co2 Absorption Using Al2o3 Nanoparticles, Safa Waleed Shakir, Saif Saleh Hussein, Shaymaa Hasan Khazaal, Hyder Akram Al-Naseri, Ahmed Mohammed Ahmed, Rana Najah Hachim, Muthanna Hikmat Al-Dahhan Aug 2024

Examination And Improvement Of The Taguchi-Based Nanofluids Impact On Co2 Absorption Using Al2o3 Nanoparticles, Safa Waleed Shakir, Saif Saleh Hussein, Shaymaa Hasan Khazaal, Hyder Akram Al-Naseri, Ahmed Mohammed Ahmed, Rana Najah Hachim, Muthanna Hikmat Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, a batch absorption reactor was used to evaluate the nanofluid of a binary aqueous solution of monoethanolamine and 2-amino-2-methyl-1-propanol (MEA/AMP) with nanoparticles of aluminium oxide (Al2O3) as a solvent used to remove carbon dioxide (CO2) from simulated flue gas. Furthermore, the application of the Taguchi experiment design method determined the optimal conditions for the absorption process. This research focuses on the CO2 absorption process and the optimal conditions related to nanoparticle addition. The main effects of using nanofluid were investigated. The concentration of nanoparticles, nanoparticle size, and stirrer speeds were …

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High-Quality Single-Step Growth Of Gaas On C-Plane Sapphire By Molecular Beam, Emmanuel Wangila, Calbi Gunder, Mohammad Zamani-Alavijeh, Fernando Maia De Oliveira, Serhii Kryvyi, Aida Sheibani, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo Aug 2024

High-Quality Single-Step Growth Of Gaas On C-Plane Sapphire By Molecular Beam, Emmanuel Wangila, Calbi Gunder, Mohammad Zamani-Alavijeh, Fernando Maia De Oliveira, Serhii Kryvyi, Aida Sheibani, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo

Physics Faculty Publications and Presentations

We report on the growth of high-quality GaAs semiconductor materials on an AlAs/sapphire substrate by molecular beam epitaxy. The growth of GaAs on sapphire centers on a new single-step growth technique that produces higher-quality material than a previously reported multi-step growth method. Omega-2theta scans confirmed the GaAs (111) orientation. Samples grown at 700 °C displayed the highest crystal quality with minimal defects and strain, evidenced by narrow FWHM values of the rocking curve. By varying the As/Ga flux ratio and the growth temperature, we significantly improved the quality of the GaAs layer on sapphire, as compared to that obtained in …

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Heat Treatment Post-Processing For The Improved Mechanical Properties Of Scalmalloy® Processed Via Directed Energy Deposition, Rachel Boillat-Newport, Sriram Praneeth Isanaka, Frank Liou Aug 2024

Heat Treatment Post-Processing For The Improved Mechanical Properties Of Scalmalloy® Processed Via Directed Energy Deposition, Rachel Boillat-Newport, Sriram Praneeth Isanaka, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

As high-strength aluminum alloys present several processability issues with additive manufacturing (AM), Scalmalloy®, an Al-Mg-Sc-Zr-based alloy, has been developed. This alloy is age-hardenable, allowing it to precipitate out a strengthening precipitate phase, Al3(Sc,Zr). The manufacturer recommends a single-stage aging treatment at 325 °C for 4 h; however, the majority of the literature studies utilize a powder bed processing known as selective laser melting (SLM) over powder-fed processing directed energy deposition (DED). This study addresses the lack of information on heat treatments for DED fabrication by exploring the application of artificial aging temperatures of 300–400 °C for 2, 4, and 6 …

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Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma Aug 2024

Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma

Economics Faculty Research & Creative Works

The electricity market crisis, driven by factors such as increased energy demand, rising fuel prices, aging infrastructure, and greenhouse gas emissions, requires a multifaceted approach including the strategic implementation of Carbon Capture and Storage (CCS) technologies, which despite high costs and potential adverse impact on renewable investments, can allow the use of fossil fuels to maintain grid stability, and simultaneously lower carbon footprint. Across the world, several nations are designing financial incentives and improving regulatory frameworks to reduce barriers to the deployment of CCS. However, it is not clearly understood whether and to what extent such policy support would affect …

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Tectonic Implications Of Seismic Anisotropy Layering Beneath The Southern Tibetan Plateau Revealed By Integrated Shear Wave Splitting And Receiver Function Analyses, Cong Shen, Stephen S. Gao, Fansheng Kong, Kelly H. Liu Aug 2024

Tectonic Implications Of Seismic Anisotropy Layering Beneath The Southern Tibetan Plateau Revealed By Integrated Shear Wave Splitting And Receiver Function Analyses, Cong Shen, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To investigate continental dynamics underneath the south-central Tibetan plateau, which composes the Himalayan, Lhasa, and Qiangtang blocks, we have conducted comprehensive examinations of seismic azimuthal anisotropy in the crust using receiver functions (RFs) and crustal and mantle anisotropy using teleseismic shear wave splitting (SWS) analysis. In the Qiangtang block, the observed predominantly E-W fast orientations from RF and SWS analyses with similar magnitude are interpreted as resulting from eastward crustal flow with minor contributions from the mantle. In the Lhasa block, the crustal anisotropy is approximately N-S oriented, which is parallel to the strike of rift basins and southward crustal …

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Design And Simulation Of A Micro-Coiled Digitally-Controlled Variable Inductor With A Monolithically Integrated Mems Switch, A. Sharaf, Sh M. Eladl, A. Nasr, M. Serry Aug 2024

Design And Simulation Of A Micro-Coiled Digitally-Controlled Variable Inductor With A Monolithically Integrated Mems Switch, A. Sharaf, Sh M. Eladl, A. Nasr, M. Serry

Faculty Journal Articles

This work introduces the design, analysis, simulation, and a standard MEMS fabrication process for a three-dimensional micro-coil with a magnetic core and a digital switch configuration using a completely integrated, fully MEMS-compatible process to achieve a digitally controlled inductance. The proposed design can also be utilized as a micro-transformer. The proposed design consists of five identical 3D coils and their corresponding MEMS switches. These coils are digitally controlled to achieve a variable inductor ranging from one-fifth of the coil inductance up to five times the coil inductance. A standard five-layer Polymumps process is proposed to fabricate the micro-coils and the …

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Evaluation Of Manual Thermal Brake Screening Systems, Jeeyen Koo, David Leddy, Jennifer Walton Aug 2024

Evaluation Of Manual Thermal Brake Screening Systems, Jeeyen Koo, David Leddy, Jennifer Walton

Kentucky Transportation Center Research Report

In 2021, manual thermal brake screening systems were installed at Lyon EB and Rowan County weigh stations. Two additional units were installed at Laurel SB and Scott County weigh stations the following year. Although this system is called a thermal brake screening system, its thermal camera images are used to find both brake and tire-related violations. At the time of this project, Lyon (EB), Rowan, and Scott County inspection locations also had tire pressure detection systems in addition to manual thermal brake screening systems. Both systems can be used to identify tire-related violations, but inspectors prefer to use the tire …

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Influence Of Aggregate Properties On Skid Resistance Of Pavement Surface Treatments, Alireza Roshan, Magdy Abdelrahman Aug 2024

Influence Of Aggregate Properties On Skid Resistance Of Pavement Surface Treatments, Alireza Roshan, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Skid resistance is a critical aspect for traffic safety since it significantly influences vehicle control and minimizes the distance required for emergency braking. The surface characteristics of pavements play a pivotal role in determining skid resistance. To achieve the optimal skid resistance performance, the pavement must sustain a specific level of friction. Thus, it is advantageous to apply surface treatments in areas that require enhanced friction. This study investigates the impact of factors such as the aggregate source, size, morphological properties, and abrasion levels on the skid resistance and frictional characteristics of a high-friction surface treatment (HFST). A complete investigation …

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