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A Review Of Optical Flow Velocimetry In Fluid Mechanics, Gauresh Raj Jassal, Bryan E. Schmidt Feb 2025

A Review Of Optical Flow Velocimetry In Fluid Mechanics, Gauresh Raj Jassal, Bryan E. Schmidt

Faculty Scholarship

Optical flow methods have been developed over the past two decades for application to particle image velocimetry (PIV) images with the goal of acquiring higher resolution measurements of the velocity field than conventional cross-correlation (CC)-based techniques. Numerous optical flow velocimetry (OFV) algorithms have been devised to solve the ill-posed optical flow problem, with various physics-inspired strategies to tailor them to fluid flows. While OFV can be applied to continuous scalar fields, it has demonstrated the most success on images of tracer particles, i.e. traditional planar PIV images. Compared to state-of-the-art CC algorithms, OFV methods have demonstrated an order of magnitude …


Inclusive Space For Everyone Door Sign (Printable 8.5 X 11 Inch), Joan H. Robinson Feb 2025

Inclusive Space For Everyone Door Sign (Printable 8.5 X 11 Inch), Joan H. Robinson

Open Educational Resources

This is a printable 8.5 x 11 inch door sign for faculty, staff, and administrators to let people know it is an inclusive space for everyone. For improved visibility, print with a color printer and cut along the dotted line.

See also: 11 x 17 inch door sign.


Internet Of Things Devices Users’ Privacy Adherence: A Case Of Digital Ignorance, Akrasia Or Exhaustion?, Philip Bazanye, Walter F. Uys, Wallace Chigona Feb 2025

Internet Of Things Devices Users’ Privacy Adherence: A Case Of Digital Ignorance, Akrasia Or Exhaustion?, Philip Bazanye, Walter F. Uys, Wallace Chigona

The African Journal of Information Systems

Internet of Things devices, such as those used in home automation, commercial and retail business, and smart cities, are vulnerable to attacks that affect all aspects of daily life. The upsurge in the use of IoT devices has increased the likelihood of cyber-attacks on end users. This research investigates the factors that influence IoT device users to adhere to privacy standards. This interpretivist exploratory research was guided by a three-phased approach. The interview questions were derived from the conceptual model and the constructs of Activity Theory, and themes were analyzed using deductive thematic analysis. The findings were elaborated with reference …


Can Chatgpt Implement Finite Element Models For Geotechnical Engineering Applications?, Hyoung Suk Suh Feb 2025

Can Chatgpt Implement Finite Element Models For Geotechnical Engineering Applications?, Hyoung Suk Suh

Faculty Scholarship

This study assesses the capability of ChatGPT to generate finite element code for geotechnical engineering applications from a set of prompts. We tested three different initial boundary value problems using a hydro-mechanically coupled formulation for unsaturated soils, including the dissipation of excess pore water pressure through fluid mass diffusion in one-dimensional space, time-dependent differential settlement of a strip footing, and gravity-driven seepage. For each case, initial prompting involved providing ChatGPT with necessary information for finite element implementation, such as balance and constitutive equations, problem geometry, initial and boundary conditions, material properties, and spatiotemporal discretization and solution strategies. Any errors and …


Si-Doped Ain Using Pulsed Metalorganic Chemical Vapor Deposition And Doping, Tariq Jamil, Abdullah Al Mamun Mazumder, Mohammod Ali, Jingyu Lin, Hongxing Jiang, Grigory Simin, M. Asif Khan Feb 2025

Si-Doped Ain Using Pulsed Metalorganic Chemical Vapor Deposition And Doping, Tariq Jamil, Abdullah Al Mamun Mazumder, Mohammod Ali, Jingyu Lin, Hongxing Jiang, Grigory Simin, M. Asif Khan

Faculty Publications

In this paper we describe a pulsed metalorganic chemical vapor deposition (MOCVD) Si-doping approach for AlN epilayers over bulk AlN. The Al-rich growth/doping conditions in the pulsed MOCVD process resulted in n-AlN layers with transmission line model currents that were an order higher than for structures on layers that were grown/doped at identical temperatures using the conventional MOCVD process. Our work demonstrated that like the other reported approaches such as UV exposure during growth, the pulsed MOCVD process is also very effective in reducing point defects by the defect quasi-Fermi level-chemical potential control.


Streamlined Production, Protection, And Purification Of Enzyme Biocatalysts Using Virus-Like Particles And A Cell-Free Protein Synthesis System, Seung O. Yang, Joseph P. Talley, Gregory H. Nielsen, Kristen M. Wilding, Bradley Charles Bundy Feb 2025

Streamlined Production, Protection, And Purification Of Enzyme Biocatalysts Using Virus-Like Particles And A Cell-Free Protein Synthesis System, Seung O. Yang, Joseph P. Talley, Gregory H. Nielsen, Kristen M. Wilding, Bradley Charles Bundy

Faculty Publications

Enzymes play an essential role in many different industries; however, their operating conditions are limited due to the loss of enzyme activity in the presence of proteases and at temperatures significantly above physiological conditions. One way to improve the stability of these enzymes against high temperatures and proteases is to encapsulate them in protective shells or virus-like particles. This work presents a streamlined, three-step, cell-free protein synthesis (CFPS) procedure that enables rapid in vitro enzyme production, targeted encapsulation in protective virus-like particles (VLPs), and facile purification using a 6× His-tag fused to the VLP coat protein. This process is performed …


Optimized Hiv/Aids Resource Allocation In Ohio: A Linear Programming Approach, Godfred Ahenkroa Kesse Feb 2025

Optimized Hiv/Aids Resource Allocation In Ohio: A Linear Programming Approach, Godfred Ahenkroa Kesse

Data Science and Data Mining

This study employs a linear and integer programming approach to optimize HIV resource allocation in Ohio, aiming to minimize new infections and enhance the impact of limited resources. With the advances in HIV prevention and treatment, Ohio faces challenges in addressing disparities in access to healthcare, particularly among high-risk populations. The proposed model integrates data on infection rates, transmission patterns, demographic factors, and cost-effectiveness to provide a decision-support framework for policymakers. Using epidemiological data and equity constraints, the model prioritizes high-risk regions and populations while ensuring fair resource distribution. Results indicate that increased funding allocations significantly enhance the potential to …


Using Unmanned Aerial Vehicles To Facilitate Traffic Incident Management, Adam William Hill Feb 2025

Using Unmanned Aerial Vehicles To Facilitate Traffic Incident Management, Adam William Hill

Theses and Dissertations

Incident management teams (IMTs) minimize crash impacts and create a safer highway network for people and communities. Research has shown that optimizing the IMT fleet has strong benefits to the roadway network, but future models indicate that increasing IMT presence may have diminishing returns after excessive roadway saturation. The Utah Department of Transportation (UDOT) would like to improve situational awareness in areas of poor or limited camera coverage, where situational awareness is typically poor. UDOT is considering the use of unmanned aerial systems (UAS) to provide live camera coverage of traffic conditions in these instances. This thesis synthesizes practice from …


Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types, Sahil Surehali, Collin Gustafson, Sayee Srikarah Volaity, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath Feb 2025

Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types, Sahil Surehali, Collin Gustafson, Sayee Srikarah Volaity, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Interest in the use of graphene to enhance the properties of cementitious materials is growing, but major impediments in implementation are the cost of graphene and changes in binder rheology attributable to these nanomaterials. This study explores the influence of novel, cost-effective, environment-friendly, and mass-producible graphene on the rheology and early-age structure development of cementitious binders. Two novel graphene types—fractal graphene (FG) and reactive graphene (RG)—are used in plain cement mixtures as well as those containing 30 % (by mass) of fly ash and/or limestone powder, at low dosages of ≤0.02 % by mass of binder. The early- and later-age …


Oxidation–Reduction Of Ti-6al-4v In Direct Energy Deposition Subject To Minimum Argon Consumption, Bharadwaja Ragampeta, Prashansa Ragampeta, Todd Sparks, Frank Liou Feb 2025

Oxidation–Reduction Of Ti-6al-4v In Direct Energy Deposition Subject To Minimum Argon Consumption, Bharadwaja Ragampeta, Prashansa Ragampeta, Todd Sparks, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ti-6Al-4V is a well-known alloy for its low density and excellent corrosion resistance, making it popular in aerospace, marine, medical, and automotive applications. However, at elevated temperatures, the alloy forms oxides, leading to embrittlement. In additive manufacturing, particularly in the direct energy deposition (DED) process, which involves high temperatures, the alloy experiences oxidation. An inert gas chamber provides shielding during the process but limits the size of the manufactured components, and deposition in a vacuum chamber can alter the chemical composition of the alloy. Local shielding is a technique generally used for such applications, but it uses a high volume …


Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement, Sai Akshay Ponduru, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Narayanan Neithalath, Gaurav Sant, Aditya Kumar Feb 2025

Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement, Sai Akshay Ponduru, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Narayanan Neithalath, Gaurav Sant, Aditya Kumar

Materials Science and Engineering Faculty Research & Creative Works

Belite calcium sulfoaluminate cement (CSAB), an alternative to Portland cement, exhibits excellent strength at both early and later ages. However, due to its high belite content, the carbon reduction from this type of cement is not sufficient when compared to other alternative cements. To further enhance CSAB's sustainability, this study investigates the performance of CSAB when partially replaced by low-carbon mineral additives (i.e., limestone and gypsum). The primary objective is to identify the optimal mixture design by incorporating gypsum and limestone to formulate a sustainable binder that maintains high compressive strength. The CSAB is replaced (with both additives) by up …


Economic Impact Of Energy Accounting Schemes For Commercial Systems On A Broiler Farm With Power Demand And Generation, Yi Liang, Michael Popp Feb 2025

Economic Impact Of Energy Accounting Schemes For Commercial Systems On A Broiler Farm With Power Demand And Generation, Yi Liang, Michael Popp

Biological and Agricultural Engineering Faculty Publications and Presentations

The aim of this study was to assess the impact of the on-farm solar photovoltaic (PV) generation to offset grid electricity consumption on a commercial poultry farm in the US. Hourly electricity production by PV systems was estimated using the System Advisor Model (SAM) of the National Renewable Energy Lab (NREL) and compared with the estimated electric load demand of a broiler house. We analyzed the economic benefits of installing solar systems of three capacities under net energy metering and net energy billing pricing scenarios. Results suggested that a smaller PV installation of 35 kWp, while substantially short of meeting …


Thermally Stimulated Stiffening And Fly Ash's Alkaline Activation By Ca(Oh)2 Addition Facilitates 3d-Printing, Xiaodi Dai, Sharu Bhagavathi Kandy, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gaedt, Samanvaya Srivastava, Gaurav Sant Feb 2025

Thermally Stimulated Stiffening And Fly Ash's Alkaline Activation By Ca(Oh)2 Addition Facilitates 3d-Printing, Xiaodi Dai, Sharu Bhagavathi Kandy, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gaedt, Samanvaya Srivastava, Gaurav Sant

Materials Science and Engineering Faculty Research & Creative Works

3D-printing could offer substantial benefits to the construction industry including the fabrication of customized/bespoke components, eliminating formwork, and reducing material waste. Despite these advantages, control of the pumpability, extrudability, and buildability of 3D-printed concrete (3DPC) remains challenging. This study demonstrates how the use of fly ash (FA) enables enhanced thermal stiffening, and rapid alkali-activation in the presence of portlandite (Ca(OH)2, CH). In general, blends of CH and FA exhibit less structural build-up at low temperatures, but upon reaching a trigger temperature of 75 °C, these blends achieve rapid stiffening, at rates of ∼800 Pa/s. The rapid stiffening arises from the …


Research On Wireless Monitoring System For Internal Temperature Field Of Coal Gangue Mountain, Xiaofei Liu, Chunhao Liang, Jifa Qian, Xiaolin Li, Xuemei Li, Baoli Li, Guang Xu, Bin Zhou Feb 2025

Research On Wireless Monitoring System For Internal Temperature Field Of Coal Gangue Mountain, Xiaofei Liu, Chunhao Liang, Jifa Qian, Xiaolin Li, Xuemei Li, Baoli Li, Guang Xu, Bin Zhou

Mining Engineering Faculty Research & Creative Works

In the long-term accumulation process, coal gangue can lead to severe consequences such as spontaneous combustion and explosions due to external factors. Additionally, the coal gangue that ignites spontaneously significantly pollutes the land and groundwater, causing serious risks to the health and safety of individuals living and working in the vicinity. Therefore, to mitigate the risk of spontaneous combustion resulting from the long-term accumulation of coal gangue, a monitoring system based on LoRa wireless communication technology is proposed to collect and monitor the internal temperature of coal gangue mountains in real time. In the laboratory, active temperature rise monitoring was …


Predicting The High Temperature Deformation Behavior Of Haynes282 By A Dislocation-Density Based Crystal Plasticity Model, Tianju Chen, Huadong Fu, Shujing Dong, Yue Zhou, Yijia Gu, Caizhi Zhou, Ridwan Sakidja Feb 2025

Predicting The High Temperature Deformation Behavior Of Haynes282 By A Dislocation-Density Based Crystal Plasticity Model, Tianju Chen, Huadong Fu, Shujing Dong, Yue Zhou, Yijia Gu, Caizhi Zhou, Ridwan Sakidja

Materials Science and Engineering Faculty Research & Creative Works

Mechanical behavior of Haynes282 is heavily dependent upon the microstructure state, calling for mesoscale model to study the relationship between the underlying microstructure and macroscopic performance. In this work, we employ crystal plasticity finite element method (CPFEM) to explore the deformation mechanisms of Hanyes282 subjected to tensile (short-term) and creep (long-term) tests. Haynes282 is a newly developed Ni-based superalloy, containing relatively low volume fraction (≤20%) of spherical γ′ precipitate phase. A dislocation-density based model is developed to describe the tensile and the creep behavior, where a dimension reduction algorithm is proposed to obtain more accurate inter-particle spacing. Furthermore, dislocation-particle interaction …


Membrane Filtration Of Nanoscale Biomaterials: Model System And Membrane Performance Evaluation For Aav2 Viral Vector Clarification And Recovery, Mara Leach, Kearstin Edmonds, Emily Ingram, Rebecca Dutch, Sumith R. Wickramasinghe, Malgorzata Chwatko, Dibakar Bhattacharyya Feb 2025

Membrane Filtration Of Nanoscale Biomaterials: Model System And Membrane Performance Evaluation For Aav2 Viral Vector Clarification And Recovery, Mara Leach, Kearstin Edmonds, Emily Ingram, Rebecca Dutch, Sumith R. Wickramasinghe, Malgorzata Chwatko, Dibakar Bhattacharyya

Chemical Engineering Faculty Publications and Presentations

The growing demand for viral vectors as nanoscale therapeutic agents in gene therapy necessitates efficient and scalable purification methods. This study examined the role of nanoscale biomaterials in optimizing viral vector clarification through a model system mimicking real AAV2 crude harvest material. Using lysed HEK293 cells and silica nanoparticles (20 nm) as surrogates for AAV2 crude harvest, we evaluated primary (depth filters) and secondary (membrane-based) filtration processes under different process parameters and solution conditions. These filtration systems were then assessed for their ability to recover nanoscale viral vectors while reducing DNA (without the need for endonuclease treatment), protein, and turbidity. …


Unlocking The Phosphorus Circularity Potential Of Corn Belt Watersheds With Biorefinery Phosphorus Recovery Incentives, Kenneth Ruffatto, Arghajeet Saha, Rebecca L. Muenich, Andrew J. Margenot, Roland D. Cusick Feb 2025

Unlocking The Phosphorus Circularity Potential Of Corn Belt Watersheds With Biorefinery Phosphorus Recovery Incentives, Kenneth Ruffatto, Arghajeet Saha, Rebecca L. Muenich, Andrew J. Margenot, Roland D. Cusick

Biological and Agricultural Engineering Faculty Publications and Presentations

As global phosphorus (P) stores rapidly decline, P fed algal blooms continue to threaten critical freshwater resources across the globe. In the Midwestern United States (US), particularly the Corn Belt, biorefineries could play a key role in addressing this issue. By recovering P from the byproducts of ethanol production these facilities could reduce the P content of distillers grain feed, thereby reducing P excreted in manures. This process could potentially divert P away from concentrated animal feeding operations (CAFOs) and toward renewable P (rP) fertilizer production utilizing the recovered P. To foster the inclusion of P recovery incentives in state …


Why Are Fairness Concerns So Important? Lessons From A Last-Mile Transportation System, Yiwei Chen, Hai Wang Feb 2025

Why Are Fairness Concerns So Important? Lessons From A Last-Mile Transportation System, Yiwei Chen, Hai Wang

Research Collection School Of Computing and Information Systems

The Last-Mile Problem refers to the provision of travel service for passengers from the nearest public transportation node to the final destination. The Last-Mile Transportation System (LMTS), which has recently emerged, provides on-demand last-mile transportation service for passengers. We consider an LMTS that consists of two types of passengers, regular-type passengers and special-type passengers (e.g., seniors, disabled people). The valuation of the last-mile service for special-type passengers is statistically higher than the one for regular-type passengers. Passengers incur disutility from waiting for the last-mile service. In this paper, we explore two fairness constraints on special-type passengers: (1) the fare for …


Recommender Systems And Reinforcement Learning For Human-Building Interaction And Context Aware Support: A Text Mining-Driven Review Of Scientific Literature, Wenhao Zhang, Matias Quintana, Clayton Miller Feb 2025

Recommender Systems And Reinforcement Learning For Human-Building Interaction And Context Aware Support: A Text Mining-Driven Review Of Scientific Literature, Wenhao Zhang, Matias Quintana, Clayton Miller

Research Collection College of Integrative Studies

The indoor environment significantly impacts human health and well-being; enhancing health and reducing energy consumption in these settings is a central research focus. With the advancement of Information and Communication Technology (ICT), recommendation systems and reinforcement learning (RL) have emerged as promising approaches to induce behavioral changes to improve the indoor environment and energy efficiency of buildings. This study aims to employ text mining and Natural Language Processing (NLP) techniques to thoroughly examine the connections among these approaches in the context of human-building interaction and occupant context-aware support. The study analyzed 27,595 articles from the ScienceDirect database, revealing extensive use …


Uav-Based Phytoforensics: Hyperspectral Image Analysis To Remotely Detect Explosives Using Maize (Zea Mays), Paul V. Manley, Stephen M. Via, Joel G. Burken Feb 2025

Uav-Based Phytoforensics: Hyperspectral Image Analysis To Remotely Detect Explosives Using Maize (Zea Mays), Paul V. Manley, Stephen M. Via, Joel G. Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Remnant explosive devices are a deadly nuisance to both military personnel and civilians. Traditional mine detection and clearing is dangerous, time-consuming, and expensive. And routine production and testing of explosives can create groundwater contamination issues. Remote detection methods could be rapidly deployed in vegetated areas containing explosives as they are known to cause stress in vegetation that is detectable with hyperspectral sensors. Hyperspectral imagery was employed in a mesocosm study comparing stress from a natural source (drought) to that of plants exposed to two different concentrations of Royal Demolition Explosive (RDX; 250 mg kg−1, 500 mg kg−1). Classification was accomplished …


Multi-Scale Modeling Of Transport Properties In Cementitious Materials With Go Admixture, Bing Liu, Weichen Kang, Weixing Lian, Feng Xing, Hongfang Sun, Hongyan Ma Feb 2025

Multi-Scale Modeling Of Transport Properties In Cementitious Materials With Go Admixture, Bing Liu, Weichen Kang, Weixing Lian, Feng Xing, Hongfang Sun, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In coastal areas, the presence of concrete cracks provides pathways for hazardous ions to ingress from the exterior into the interior of concrete, while the migration of the ions further accelerates concrete deterioration and causes durability problems. The incorporation of graphene oxide (GO) into concrete can inhibit crack initiation and development starting at the nanoscale, improving the concrete microstructure, thereby affecting concrete's resistance to hazardous ion transport and the resulting deterioration. In this study, a multi-scale transport model for cementitious materials with a GO admixture was established to predict the resistance to hazardous ions. Based on the determination of hydration …


Assessing The Impact Of Radar-Rainfall Uncertainty On Streamflow Simulation, Nicolás Velásquez, Witold F. Krajewski, Bong Chul Seo Feb 2025

Assessing The Impact Of Radar-Rainfall Uncertainty On Streamflow Simulation, Nicolás Velásquez, Witold F. Krajewski, Bong Chul Seo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hydrological models and quantitative precipitation estimation (QPE) are critical elements of flood forecasting systems. Both are subject to considerable uncertainties. Quantifying their relative contribution to the forecasted streamflow and flood uncertainty has remained challenging. Past work documented in the literature focused on one of these elements separately from the other. With this in mind, we present a systematic approach to assess the impact of QPE uncertainty in streamflow forecasting. Our approach explores the operational Iowa Flood Center (IFC) hydrological model performance after altering two radar-based QPE products. We ran the Hillslope Link Model (HLM) for Iowa between 2015 and 2020, …


Nonlinear Self-Synchronizing Current Control For Single-Phase Ac Inverters, Shruti Pandey, Michael Mclntyre Feb 2025

Nonlinear Self-Synchronizing Current Control For Single-Phase Ac Inverters, Shruti Pandey, Michael Mclntyre

Electrical and Computer Engineering Faculty Research & Creative Works

Grid-connected single-phase inverters require accurate phase detection for synchronization and power control. Traditionally, phase-locked loops (PLLs) are used to estimate grid parameters. This paper proposes a novel approach that determines the grid phase angle using only current feedback, eliminating the need for grid voltage measurements or cascaded control schemes. The proposed method integrates a phase angle observer with a current controller to regulate real and reactive power. Lyapunov stability analysis and hardware experiments validate the effectiveness of the approach.


Simulation-Based Models For Postearthquake Response: A Survey And Research Directions, Abhijit Gosavi, Lauryn A. Spearing, Lesley H. Sneed Feb 2025

Simulation-Based Models For Postearthquake Response: A Survey And Research Directions, Abhijit Gosavi, Lauryn A. Spearing, Lesley H. Sneed

Engineering Management and Systems Engineering Faculty Research & Creative Works

Computer simulation is increasingly being used by emergency planners as a tool to improve disaster response given that it can model real-world scenarios, such as earthquakes. Although there has been an increase in simulation research focused on disaster response, much of this literature is from disparate fields and across disaster scenarios. To bridge this gap, this paper surveys simulation-based models for post-earthquake response from the year 2000 onward. Advantages of simulation over closed-form statistical models are discussed. Three main subproblems in post-earthquake response models are explored: (1) service distribution (e.g., food, water), (2) infrastructure restoration (at the building and transportation …


Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy, Agustin Morales-Aragon, Daniel Sánchez-Rodas, Guillermo Ríos, Michael S. Moats Feb 2025

Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy, Agustin Morales-Aragon, Daniel Sánchez-Rodas, Guillermo Ríos, Michael S. Moats

Materials Science and Engineering Faculty Research & Creative Works

The behavior of impurities in cast copper was investigated to simulate production with increased utilization of secondary sources within the framework of a circular economy. The incorporation of impurities, particularly Ni, Sn, and Sb, from recycled Cu may significantly impact the electrorefining process. In this study, commercial anodes were doped with Ni, Sn, and Sb concentrations of 2500–6500 g/t, 300–900 g/t, and 450–950 g/t, respectively. Anode concentrations of Pb and Bi were maintained at 1000 g/t and 350 g/t, respectively. As concentrations were examined at two levels, 860 or 1700 g/t, depending on the commercial anode used to create the …


Blast Tube Design: How Shape And Size Influence The Resultant Shock Wave, R. L. Bauer, C. E. Johnson Feb 2025

Blast Tube Design: How Shape And Size Influence The Resultant Shock Wave, R. L. Bauer, C. E. Johnson

Mining Engineering Faculty Research & Creative Works

Shock tubes and tunnels are often used in research settings as a way of producing high pressure shock waves in a smaller footprint or without the use of explosives. However, there is no standard geometric design across laboratories. Peak pressure is a significant parameter for characterizing a shock wave. However, different tube configurations could also affect parameters such as impulse and duration, yet no research has investigated how the scale of the tube affects the overall waveform shape. To understand the implications of shock tube design, tubes with a constant length to diameter ratio were evaluated to determine how tube …


A Comprehensive Study Of Cooling Rate Effects On Diffusion, Microstructural Evolution, And Characterization Of Aluminum Alloys, Atiqur Rahman, Sriram Praneeth Isanaka, Frank Liou Feb 2025

A Comprehensive Study Of Cooling Rate Effects On Diffusion, Microstructural Evolution, And Characterization Of Aluminum Alloys, Atiqur Rahman, Sriram Praneeth Isanaka, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Cooling Rate (CR) definitively influences the microstructure of metallic parts manufactured through various processes. Factors including cooling medium, surface area, thermal conductivity, and temperature control can influence both predicted and unforeseen impacts that then influence the results of mechanical properties. This comprehensive study explores the impact of CRs in diffusion, microstructural development, and the characterization of aluminum alloys and the influence of various manufacturing processes and post-process treatments, and it studies analytical models that can predict their effects. It examines a broad range of CRs encountered in diverse manufacturing methods, such as laser powder bed fusion (LPBF), directed energy deposition …


Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat Feb 2025

Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While self-consolidating concrete (SCC) has emerged as a highly effective approach for the repair of concrete structures, there have been few investigations regarding the effect of the combination of different fiber and shrinkage-mitigating material types (shrinkage-reducing admixture, SRA; superabsorbent polymer, SAP; and expansive agent, EA) on the flexural behavior of repaired structures. This study aims to explore the influence of three different shrinkage-mitigating materials (1.25%–2.5 % SRA, 4%–8% EA, and 0.2%–0.4 % SAP), four fiber types (two macro synthetic fibers, MSFA and MSFB; 5D hooked steel fibers, 5D; a combination of 80 % 3D hooked steel +20 % short steel …


Elevated Temperature Performance: Arc-Jet Testing Of Carbon Fiber Reinforced Zrb2 Bars Up To 2200 °C For Strength Retention Assessment, D. Sciti, A. Vinci, L. Zoli, P. Galizia, M. Mor, W. Fahrenholtz, S. Mungiguerra, R. Savino, A. M. Caporale, A. Airoldi Feb 2025

Elevated Temperature Performance: Arc-Jet Testing Of Carbon Fiber Reinforced Zrb2 Bars Up To 2200 °C For Strength Retention Assessment, D. Sciti, A. Vinci, L. Zoli, P. Galizia, M. Mor, W. Fahrenholtz, S. Mungiguerra, R. Savino, A. M. Caporale, A. Airoldi

Materials Science and Engineering Faculty Research & Creative Works

For the first time, ultra-high temperature ceramic matrix composite bars were tested inside an arc-jet facility to investigate the impact of oxidation damage on strength retention. The composite bars, which were based on a ZrB2 / SiC matrix reinforced with 45 vol% carbon fibers, were produced by slurry impregnation and sintering. The first batch was tested under 3-point (pt) bending, and two additional batches were exposed to plasma of dissociated air up to a temperature of 2200 °C for 2 min or 2.2 min and then subjected to 3-pt bending. More than 75% of the initial strength was retained even …


Influence Of Temperature, Oxygen Partial Pressure, And Microstructure On The High-Temperature Oxidation Behavior Of The Sic Layer Of Triso Particles, Visharad Jalan, Adam Bratten, Meng Shi, Tyler Gerczak, Haiyan Zhao, Jonathan D. Poplawsky, Xiaoqing He, Grant Helmreich, Haiming Wen Feb 2025

Influence Of Temperature, Oxygen Partial Pressure, And Microstructure On The High-Temperature Oxidation Behavior Of The Sic Layer Of Triso Particles, Visharad Jalan, Adam Bratten, Meng Shi, Tyler Gerczak, Haiyan Zhao, Jonathan D. Poplawsky, Xiaoqing He, Grant Helmreich, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Tri structural isotropic (TRISO)-coated fuel particles are designed for use in high-temperature gas-cooled nuclear reactors, featuring a structural SiC layer that may be exposed to oxygen-rich environments over 1000 °C. Surrogate TRISO particles were tested in 0.2–20 kPa O2 atmospheres to observe the differences in oxidation behavior. Oxide growth mechanisms remained consistent from 1200–1600 °C for each PO2, with activation energies of 228 ± 7 kJ/mol for 20 kPa O2 and 188 ± 8 kJ/mol for 0.2 kPa O2. At 1600 °C, kinetic analysis revealed a change in oxide growth mechanisms between 0.2 and 6 kPa O2. In 0.2 kPa …