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Study Of Gas Holdup Distribution In Cylindrical Split Airlift Reactor By Using Gamma-Ray Densitometry (Grd), Abbas J. Sultan, Laith S. Sabri, Hasan Shakir Majdi, Shadha K. Jebur, Muthanna H. Al-Dahhan May 2022

Study Of Gas Holdup Distribution In Cylindrical Split Airlift Reactor By Using Gamma-Ray Densitometry (Grd), Abbas J. Sultan, Laith S. Sabri, Hasan Shakir Majdi, Shadha K. Jebur, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The local gas holdup details and behaviors in the cylindrical split airlift column by using an unconventional gamma-ray densitometry (GRD) measurement in non-invasive manner technique was investigated for the first time in this work for such kind of airlift column. With different gas velocities, 1, 2, and 3 cm/s, at three various axial planes (different levels) in z = 3, 60, and 110 cm were studied for local distribution in radial gas holdup profiles. The distribution in gas–liquid phases (air-water system) in the entire split reactor column, in the rising and descending sides, including their behavior in the upper and …

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Process Evaluation And Kinetic Analysis Of 3d-Printed Monoliths Comprised Of Cao And Cr/H-Zsm-5 In Combined Co2 Capture-C2h6 Oxidative Dehydrogenation To C2h4, Khaled Baamran, Shane Lawson, Ali A. Rownaghi, Fateme Rezaei May 2022

Process Evaluation And Kinetic Analysis Of 3d-Printed Monoliths Comprised Of Cao And Cr/H-Zsm-5 In Combined Co2 Capture-C2h6 Oxidative Dehydrogenation To C2h4, Khaled Baamran, Shane Lawson, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, dual-function materials (DFMs) comprised of CaO and Cr/H-ZSM-5 were formulated in 3D-printed monolithic structures and investigated in a combined process for capture and utilization of CO2 in oxidative dehydrogenation of C2H6 to C2H4 (CO2-ODHE). Various formulation strategies were employed to fabricate these DFM structures. Two bed designs were considered: i) a layered-bed in which adsorbent (CaO) and catalyst were printed separately and stacked on top of each other, and ii) a single-layer bed where the adsorbent-catalyst materials were 3D-printed into a singular monolith and loaded into the bed …

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Integration Of Dynamic Growth Modeling And Hydrodynamics In An Internal-Loop Split Photobioreactor, Laith S. Sabri, Aastha Ojha, Abbas J. Sultan, Muthanna H. Aldahhan May 2022

Integration Of Dynamic Growth Modeling And Hydrodynamics In An Internal-Loop Split Photobioreactor, Laith S. Sabri, Aastha Ojha, Abbas J. Sultan, Muthanna H. Aldahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, new high-quality experimental data for culturing green microalgae Scenedesmus in tubular and cylindrical split airlift photobioreactors were obtained under different operating conditions. The obtained experimental data of culturing microalgae Scenedesmus in a tubular photobioreactor were used for determining the kinetic parameters of the photosynthetic reaction. On the other hand, the culturing of green microalgae in a split airlift photobioreactor was used to measure the microalgae cell trajectory using an advanced radioactive particle tracking (RPT) technique. The obtained results in terms of kinetic parameters of the photosynthetic reaction and microalgae cell trajectory were integrated for the first time …

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Random Trilobe Packing Using Rigid Body Approach And Local Gas-Liquid Hydrodynamics Simulation Through Cfd With Experimental Validation, Binbin Qi, Sebastián Uribe, Omar Farid, Muthanna H. Al-Dahhan May 2022

Random Trilobe Packing Using Rigid Body Approach And Local Gas-Liquid Hydrodynamics Simulation Through Cfd With Experimental Validation, Binbin Qi, Sebastián Uribe, Omar Farid, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

It is quite difficult to measure the local information of the gas/liquid flow inside random packed extrudate catalyst beds in a large scale. Obtaining the local information through computational fluid dynamic (CFD) simulations in such system is also difficult due to the complexity of random particle packing and two-phase flow simulation. An efficient packing scheme was implemented to randomly pack 2917 trilobe particles (10 cm in height) in a 2-inch column to represent the trickle bed reactor (TBR) based on the rigid body approach. The generated geometry was used to define the computational domain for the two-phase hydrodynamics simulation based …

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Hydration Of High-Alumina Calcium Aluminate Cements With Carbonate And Sulfate Additives, Jonathan Lapeyre, Sai Akshay Ponduru, Monday Uchenna Okoronkwo, Hongyan Ma, Aditya Kumar May 2022

Hydration Of High-Alumina Calcium Aluminate Cements With Carbonate And Sulfate Additives, Jonathan Lapeyre, Sai Akshay Ponduru, Monday Uchenna Okoronkwo, Hongyan Ma, Aditya Kumar

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study investigated the influence of limestone (LS) and calcium sulfate (C$) mineral additives on the hydration kinetics of high-α-Al2O3 calcium aluminate cement (CAC) utilizing experimental techniques and thermodynamic simulations. Increasing the replacement level of limestone or calcium sulfate increased the cumulative heat of the hydration reaction. The limestone exhibited limited acceleratory effects to the CAC hydration kinetics due to the coarseness of the powder. The coarse particle size distribution limited any heterogenous nucleation that would have occurred with a finer particle size as well as the intrinsic insolubility kinetically limits the formation of monocarboaluminate phases. Conversely, …

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Liquid And Solids Phase Backmixing In A Bubble And Slurry Bubble Column Using A Virtual Tracer Response Methodology Based On The Trajectory Data Of The Radioactive Particle Tracking (Rpt) Technique, Lu Han, Premkumar Kamalanathan, Muthanna H. Al-Dahhan May 2022

Liquid And Solids Phase Backmixing In A Bubble And Slurry Bubble Column Using A Virtual Tracer Response Methodology Based On The Trajectory Data Of The Radioactive Particle Tracking (Rpt) Technique, Lu Han, Premkumar Kamalanathan, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Virtual tracer response methodology developed based on the trajectory data of the computer aided radioactive particle tracking (CARPT) technique was demonstrated. The demonstrated virtual tracer technique has advantages of non-invasiveness, near perfect injection/sampling, and flexibility in choosing the sampling/injection boundaries in a specific spatial pattern. With the developed virtual tracer technique, liquid and solids back mixing was investigated at the conditions mimicking Fischer-Tropsch synthesis. Experiments were conducted at different pressure, solids loading, and superficial gas velocity. The axial dispersion model (ADM) and recirculation and cross flow dispersion (RCFD) models were used to model the liquid mixing. Transient sedimentation dispersion model …

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Review Of Biomechanical Studies And Finite Element Modeling Of Sternal Closure Using Bio-Active Adhesives, Amatulraheem Al-Abassi, Marcello Papini, Mark R. Towler May 2022

Review Of Biomechanical Studies And Finite Element Modeling Of Sternal Closure Using Bio-Active Adhesives, Amatulraheem Al-Abassi, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The most common complication of median sternotomy surgery is sternum re-separation after sternal fixation, which leads to high rates of morbidity and mortality. The adhered sternal fixation technique comprises the wiring fixation technique and the use of bio-adhesives. Adhered sternal fixation techniques have not been extensively studied using finite element analysis, so mechanical testing studies and finite element analysis of sternal fixation will be presented in this review to find the optimum techniques for simulating sternal fixation with adhesives. The optimal wiring technique should enhance bone stability and limit sternal displacement. Bio-adhesives have been proposed to support sternal fixation, as …

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Solid-State Formation Mechanisms Of Core–Shell Microstructures In (Zr,Ta)B2 Ceramics, Anna N. Dorner, Frédéric Monteverde, William Fahrenholtz, Gregory E. Hilmas May 2022

Solid-State Formation Mechanisms Of Core–Shell Microstructures In (Zr,Ta)B2 Ceramics, Anna N. Dorner, Frédéric Monteverde, William Fahrenholtz, Gregory E. Hilmas

Materials Science and Engineering Faculty Research & Creative Works

Transition metal diborides with core–shell microstructures have demonstrated excellent mechanical properties at elevated temperatures. Previous studies concluded that core–shell microstructures were formed by liquid-assisted mass transport mechanisms, but in this study, we propose a solid-state formation mechanism for core-shell microstructures in (Zr,Ta)B2 ceramics produced by reaction hot pressing and in ZrB2-TaB2 diffusion couples. Diffusion couple experiments demonstrated that core–shell microstructures developed as a result of Ta diffusion along ZrB2 grain boundaries, which occurred concurrently with lattice diffusion of Ta into ZrB2. These findings suggest that with optimization of batching and processing parameters, core–shell diboride materials may be formed through solid-state …

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Use Of Saturated Lightweight Sand To Improve The Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu May 2022

Use Of Saturated Lightweight Sand To Improve The Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper studied the influence of pre-saturated lightweight sand (LWS) on the mechanical and microstructural properties of UHPC cast with steel fiber alignment. The changes in hydration kinetics, porosity, nano-mechanical, and mechanical properties were studied. The LWS was used at 0–50% replacement volumes of total sand. Predominant fiber alignment was favored through a flow-induced casting method during casting of flexural prisms. Experiment results showed that the 28-d autogenous shrinkage was decreased from 450 to 275 μm/m with the LWS content increasing from 0 to 50%. The addition of 20% LWS led to maximum increases of 15%, 15%, and 20% in …

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Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi May 2022

Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Introduction: Determining the biological significance of pteridines in cancer development and progression remains an important step in understanding the altered levels of urinary pteridines seen in certain cancers. Our companion study revealed that several folate-derived pteridines and lumazines correlated with tumorigenicity in an isogenic, progressive breast cancer cell model, providing direct evidence for the tumorigenic origin of pteridines. Objectives: This study sought to elucidate the pteridine biosynthetic pathway in a progressive breast cancer model via direct pteridine dosing to determine how pteridine metabolism changes with tumorigenicity. Methods: First, MCF10AT breast cancer cells were dosed individually with 15 pteridines to determine …

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Quantitative Holistic Assessment Of Implementing Collaborative Planning Practices, Amr Elsayegh, Islam H. El-Adaway May 2022

Quantitative Holistic Assessment Of Implementing Collaborative Planning Practices, Amr Elsayegh, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Practices of collaborative planning - as related to novel project delivery methods, information technologies, lean construction, and supply chain practices - can impact the cost and schedule performance of projects in the architectural, engineering, and construction (AEC) industry. However, there is a lack of research providing a quantitative holistic assessment of implementing collaborative planning practices. This paper fills this knowledge gap. Using an interdependent multistep research methodology, the authors (1) analyzed a holistic literature-based list of collaborative planning risks using 46 responses from industry expert surveys; (2) calculated the criticality of these risks and compared the obtained results using Spearman …

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Theoretical And Numerical Evidence For The Potential Realization Of The Peregrine Soliton In Repulsive Two-Component Bose-Einstein Condensates, A. Romero-Ros, Garyfallia C. Katsimiga, Simeon I. Mistakidis, B. Prinari, G. Biondini, P. Schmelcher, P. G. Kevrekidis May 2022

Theoretical And Numerical Evidence For The Potential Realization Of The Peregrine Soliton In Repulsive Two-Component Bose-Einstein Condensates, A. Romero-Ros, Garyfallia C. Katsimiga, Simeon I. Mistakidis, B. Prinari, G. Biondini, P. Schmelcher, P. G. Kevrekidis

Physics Faculty Research & Creative Works

The Present Work Is Motivated By The Recent Experimental Realization Of The Townes Soliton In An Effective Two-Component Bose-Einstein Condensate By B. Bakkali-Hassan Et Al. [Phys. Rev. Lett. 127, 023603 (2021)PRLTAO0031-900710.1103/PhysRevLett.127.023603]. Here, We Use A Similar Multicomponent Platform To Exemplify Theoretically And Numerically, Within The Mean-Field Gross-Pitaevskii Framework, The Potential Toward The Experimental Realization Of A Different Fundamental Wave Structure, Namely The Peregrine Soliton. Leveraging The Effective Attractive Interaction Produced Within The Mixture's Minority Species In The Immiscible Regime, We Illustrate How Initialization Of The Condensate With A Suitable Power-Law Decaying Spatial Density Pattern Yields The Robust Emergence Of The …

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Counterflow Dynamics Of Two Correlated Impurities Immersed In A Bosonic Gas, Friethjof Theel, Simeon I. Mistakidis, Kevin Keiler, Peter Schmelcher May 2022

Counterflow Dynamics Of Two Correlated Impurities Immersed In A Bosonic Gas, Friethjof Theel, Simeon I. Mistakidis, Kevin Keiler, Peter Schmelcher

Physics Faculty Research & Creative Works

The Counterflow Dynamics Of Two Correlated Impurities In A Double Well Coupled To A One-Dimensional Bosonic Medium Is Explored. We Determine The Ground-State Phase Diagram Of The System According To The Impurity-Medium Entanglement And The Impurities' Two-Body Correlations. Specifically, Bound Impurity Structures Reminiscent Of Bipolarons For Strong Attractive Couplings As Well As Configurations With Two Clustered Or Separated Impurities In The Repulsive Case Are Identified. The Interval Of Existence Of These Phases Depends Strongly On The Impurity-Impurity Interactions And External Confinement Of The Medium. Accordingly The Impurities' Dynamical Response, Triggered By Suddenly Ramping Down The Central Potential Barrier, Is Affected …

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Sizing Battery Energy Storage And Pv System In An Extreme Fast Charging Station Considering Uncertainties And Battery Degradation, Waqas Ur Rehman, Rui Bo, Hossein Mehdipourpicha, Jonathan W. Kimball May 2022

Sizing Battery Energy Storage And Pv System In An Extreme Fast Charging Station Considering Uncertainties And Battery Degradation, Waqas Ur Rehman, Rui Bo, Hossein Mehdipourpicha, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents mixed integer linear programming (MILP) formulations to obtain optimal sizing for a battery energy storage system (BESS) and solar generation system in an extreme fast charging station (XFCS) to reduce the annualized total cost. The proposed model characterizes a typical year with eight representative scenarios and obtains the optimal energy management for the station and BESS operation to exploit the energy arbitrage for each scenario. Contrasting extant literature, this paper proposes a constant power constant voltage (CPCV) based improved probabilistic approach to model the XFCS charging demand for weekdays and weekends. This paper also accounts for the …

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Recovery Of Degraded Ni-Rich Nmc811 Particles For Lithium-Ion Batteries, Han Yu, Yan Gao, James Kirtley, Gabriel Borgmeyer, Xiaoqing He, Xinhua Liang May 2022

Recovery Of Degraded Ni-Rich Nmc811 Particles For Lithium-Ion Batteries, Han Yu, Yan Gao, James Kirtley, Gabriel Borgmeyer, Xiaoqing He, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nickel-rich cathode materials attract a lot of attention due to their high energy density. However, their sensitivity to air and moisture hinders their practical applications. Exposing Ni-rich NMC in the air will produce by-products that are not conducive to lithium-ion transmission. Water washing can be used to remove by-products on the surface, but it can also introduce new problems, such as the generation of NiO on the particle surface, which will reduce the electrochemical performance of the material. In this study, Al2O3atomic layer deposition (ALD) was applied on degraded NMC811 particles to recover the electrochemical performance …

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Lithospheric Structure Underneath The Archean Tanzania Craton And Adjacent Regions From A Joint Inversion Of Receiver Functions And Rayleigh-Wave Phase Velocity Dispersion, Tuo Wang, Stephen S. Gao, Qiuyue Yang, Ling Chen, Kelly H. Liu May 2022

Lithospheric Structure Underneath The Archean Tanzania Craton And Adjacent Regions From A Joint Inversion Of Receiver Functions And Rayleigh-Wave Phase Velocity Dispersion, Tuo Wang, Stephen S. Gao, Qiuyue Yang, Ling Chen, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Lithospheric structure beneath the Archean Tanzania craton and adjacent regions, including segments of the East African rift system (EARS) and the Proterozoic-early Paleozoic orogenic belts between the EARS and the craton, is imaged by a joint inversion of receiver functions and Rayleigh wave dispersion measurements derived from ambient seismic noise for shorter periods and teleseismic data for longer periods. Our resulting crustal thickness, crustal VP= VS measurements and 3D shear-wave velocity model for the upper 120 km show a clear spatial correspondence with major surficial geological features. The new results suggest the presence of a mafic layer in the bottom …

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An Interesting Piece Of The 'Kybosh' Puzzle: 'Mr. Kybosh' In An 1831 Poem - Where Did His Name Come From?, Gerald Leonard Cohen May 2022

An Interesting Piece Of The 'Kybosh' Puzzle: 'Mr. Kybosh' In An 1831 Poem - Where Did His Name Come From?, Gerald Leonard Cohen

Arts, Languages and Philosophy Faculty Research & Creative Works

No abstract provided.

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Defining The Collapse Point In Colloidal Unimolecular Polymer (Cup) Formation, Ashish Zore, Peng Geng, Yuwei Zhang, Michael R. Van De Mark May 2022

Defining The Collapse Point In Colloidal Unimolecular Polymer (Cup) Formation, Ashish Zore, Peng Geng, Yuwei Zhang, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

Colloidal unimolecular polymer (CUP) particles were made using polymers with different ratios of hydrophobic and hydrophilic monomers via a self-organization process known as water reduction. The water-reduction process and the collapse of the polymer chain to form a CUP were tracked using viscosity measurements as a function of composition. A vibration viscometer, which allowed for viscosity measurement as the water was being added during the water-reduction process, was utilized. The protocol was optimized and tested for factors such as temperature control, loss of material, measurement stability while stirring, and changes in the solution volume with the addition of water. The …

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Defining The Collapse Point In Colloidal Unimolecular Polymer (Cup) Formation, Ashish Zore, Peng Geng, Yuwei Zhang, Michael R. Van De Mark May 2022

Defining The Collapse Point In Colloidal Unimolecular Polymer (Cup) Formation, Ashish Zore, Peng Geng, Yuwei Zhang, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

Colloidal unimolecular polymer (CUP) particles were made using polymers with different ratios of hydrophobic and hydrophilic monomers via a self-organization process known as water reduction. The water-reduction process and the collapse of the polymer chain to form a CUP were tracked using viscosity measurements as a function of composition. A vibration viscometer, which allowed for viscosity measurement as the water was being added during the water-reduction process, was utilized. The protocol was optimized and tested for factors such as temperature control, loss of material, measurement stability while stirring, and changes in the solution volume with the addition of water. The …

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Construction And Demonstration Of A 6–18 Ghz Microwave Three-Wave Mixing Experiment Using Multiple Synchronized Arbitrary Waveform Generators, Nicole T. Moon, Klaus Woelk, Garry S. Grubbs May 2022

Construction And Demonstration Of A 6–18 Ghz Microwave Three-Wave Mixing Experiment Using Multiple Synchronized Arbitrary Waveform Generators, Nicole T. Moon, Klaus Woelk, Garry S. Grubbs

Chemistry Faculty Research & Creative Works

This manuscript details the construction and demonstration of the first known microwave three-wave mixing (M3WM) experiment utilizing multiple arbitrary waveform generators (AWGs) completely operable in the 6–18 GHz frequency range for use in chirality determination and quantification. Many M3WM techniques, which involve two orthogonal, subsequent Rabi π/2 and π microwave pulses, suffer from flexibility in pulse types and timings as well as frequency due to most instruments only using one, one-channel AWG and the M3WM probability decreasing with an increasing quantum number, J. In this work, we presented an M3WM instrument that allows that flexibility by introducing multiple, synchronized AWGs …

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Techno-Economic Feasibility Analysis Of A Fully Mobile Radiation Oncology System Using Monte Carlo Simulation, Alex T. Price, Casey I. Canfield, Geoffrey D. Hugo, James A. Kavanaugh, Lauren E. Henke, Eric Laugeman, Pamela Samson, Clair Reynolds-Kueny, Elizabeth A. Cudney May 2022

Techno-Economic Feasibility Analysis Of A Fully Mobile Radiation Oncology System Using Monte Carlo Simulation, Alex T. Price, Casey I. Canfield, Geoffrey D. Hugo, James A. Kavanaugh, Lauren E. Henke, Eric Laugeman, Pamela Samson, Clair Reynolds-Kueny, Elizabeth A. Cudney

Engineering Management and Systems Engineering Faculty Research & Creative Works

PURPOSE Disparities in radiation oncology (RO) can be attributed to geographic location, socioeconomic status, race, sex, and other societal factors. One potential solution is to implement a fully mobile (FM) RO system to bring radiotherapy to rural areas and reduce barriers to access. We use Monte Carlo simulation to quantify techno-economic feasibility with uncertainty, using two rural Missouri scenarios. METHODS Recently, a semimobile RO system has been developed by building an o-ring linear accelerator (linac) into a mobile coach that is used for temporary care, months at a time. Transitioning to a more FM-RO system, which changes location within a …

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Mechanical Properties Of Fusion Welded Ceramics In The Sic-Zrb2 And Sic-Zrb2-Zrc Systems, Jecee D. Jarman, William Fahrenholtz, Greg Hilmas, Jeremy Lee Watts, Derek S. King May 2022

Mechanical Properties Of Fusion Welded Ceramics In The Sic-Zrb2 And Sic-Zrb2-Zrc Systems, Jecee D. Jarman, William Fahrenholtz, Greg Hilmas, Jeremy Lee Watts, Derek S. King

Materials Science and Engineering Faculty Research & Creative Works

Mechanical properties of welded SiC-ZrB2 and SiC-ZrB2-ZrC ceramics were measured up to 1700 °C. Commercial powders were hot pressed, machined into coupons, and preheated to 1600 °C before joining the ceramics using either tungsten inert gas welding or plasma arc welding. Toughness of the parent materials was 3–4 MPa*m1/2 which decreased after welding to 2–2.5 MPa*m1/2. Strength of the SiC-ZrB2-ZrC parent material was ~700 MPa at 25 °C, ~300 MPa at 1700 °C, and retained 40–60% of this strength once welded. Strength of the SiC-ZrB2 parent material was ~600 MPa at 25 °C and 1700 °C and retained 20–30% of …

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Pressureless Sintering Of Zirconium Diboride With Carbon And Boron Carbide Nanopowder, Eric W. Neuman, Gregory E. Hilmas, William Fahrenholtz May 2022

Pressureless Sintering Of Zirconium Diboride With Carbon And Boron Carbide Nanopowder, Eric W. Neuman, Gregory E. Hilmas, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

Zirconium diboride ceramics with and without carbon and boron carbide nano powder additives were prepared by ball milling with ZrB2 grinding media and pressureless sintering. Additions of up to 1 wt% nano-B4C and 0.5 wt% C were made to the ZrB2 powder. The materials were then sintered between 1800 and 2300 °C for between 90 and 360 min in an Ar/10H2 atmosphere. After sintering at 2200 °C for 90 min, densities ranged from 88.3 to 90.7% for the ZrB2 with 0–1.0% nano-B4C addition. Carbon additions of 0.5 wt% and nano-B4C additions from 0 to 1.0 wt% resulted in densities ranging …

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Interpolation And Extrapolation Of Optimally Fitted Kinematic Error Model For Five-Axis Machine Tools, Le Ma, Douglas A. Bristow, Robert G. Landers May 2022

Interpolation And Extrapolation Of Optimally Fitted Kinematic Error Model For Five-Axis Machine Tools, Le Ma, Douglas A. Bristow, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Machine tool geometric errors are frequently corrected by populating compensation tables that contain position-dependent offsets to each commanded axis position. While each offset can be determined by directly measuring the individual geometric error at that location, it is often more efficient to compute the compensation using a volumetric error model derived from measurements across the entire axis space. However, interpolation and extrapolation of measurements, once explicit in direct measurement methods, become implicit and obfuscated in the curve-fitting process of volumetric error methods. The drive to maximize model accuracy while minimizing measurement sets can lead to significant model errors in workspace …

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Semi-Annual Progress Report #10, Missouri University Of Science And Technology. Inspire - University Transportation Center Apr 2022

Semi-Annual Progress Report #10, Missouri University Of Science And Technology. Inspire - University Transportation Center

Semi-Annual Progress Reports

No abstract provided.

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Structural Health Monitoring: From Virtual Shakers To Machine Learning, Ahsan Kareem Apr 2022

Structural Health Monitoring: From Virtual Shakers To Machine Learning, Ahsan Kareem

Abbett Distinguished Seminar Series

Structural health monitoring (SHM) is a critical means of assessing the performance of aging civil infrastructure. Earlier studies used heavy dynamic shakers to assess the dynamics of structures, which are unwieldy and reliance has been shifted to ambient vibration of structures to extract dynamic features. This study introduces a “virtual shaker” concept that effectively replaces the physical shaker and provides all the desired features for SHM. Examples are provided along with an App that facilitates the use of this concept to identify dynamic features. A traditional structural health monitoring (SHM) operation requires a wired system, which is often termed “hub …

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Regularized Inversion Of Aerosol Hygroscopic Growth Factor Probability Density Function: Application To Humidity-Controlled Fast Integrated Mobility Spectrometer Measurements, Jiaoshi Zhang, Yang Wang, Steven Spielman, Susanne Hering, Jian Wang Apr 2022

Regularized Inversion Of Aerosol Hygroscopic Growth Factor Probability Density Function: Application To Humidity-Controlled Fast Integrated Mobility Spectrometer Measurements, Jiaoshi Zhang, Yang Wang, Steven Spielman, Susanne Hering, Jian Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aerosol hygroscopic growth plays an important role in atmospheric particle chemistry and the effects of aerosol on radiation and hence climate. The hygroscopic growth is often characterized by a growth factor probability density function (GF-PDF), where the growth factor is defined as the ratio of the particle size at a specified relative humidity to its dry size. Parametric, least-squares methods are the most widely used algorithms for inverting the GF-PDF from measurements of the humidified tandem differential mobility analyzer (HTDMA) and have been recently applied to the GF-PDF inversion from measurements of the humidity-controlled fast integrated mobility spectrometer (HFIMS). However, …

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Accelerating Serverless Computing By Harvesting Idle Resources, Hanfei Yu, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park Apr 2022

Accelerating Serverless Computing By Harvesting Idle Resources, Hanfei Yu, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park

Computer Science Faculty Research & Creative Works

Serverless computing automates fine-grained resource scaling and simplifies the development and deployment of online services with stateless functions. However, it is still non-trivial for users to allocate appropriate resources due to various function types, dependencies, and input sizes. Misconfiguration of resource allocations leaves functions either under-provisioned or over-provisioned and leads to continuous low resource utilization. This paper presents Freyr, a new resource manager (RM) for serverless platforms that maximizes resource efficiency by dynamically harvesting idle resources from over-provisioned functions to under-provisioned functions. Freyr monitors each function's resource utilization in real-time, detects over-provisioning and under-provisioning, and learns to harvest idle resources …

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Direct Numerical Simulation Of Hypersonic Turbulent Boundary Layers: Effect Of Spatial Evolution And Reynolds Number, Junji Huang, Lian Duan, Meelan M. Choudhari Apr 2022

Direct Numerical Simulation Of Hypersonic Turbulent Boundary Layers: Effect Of Spatial Evolution And Reynolds Number, Junji Huang, Lian Duan, Meelan M. Choudhari

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct numerical simulations (DNS) are performed to investigate the spatial evolution of flat-plate zero-pressure-gradient turbulent boundary layers over long streamwise domains (Formula Presented, with Formula Presented the inflow boundary-layer thickness) at three different Mach numbers, Formula Presented, Formula Presented and Formula Presented, with the surface temperatures ranging from Quasi adiabatic to highly cooled conditions. The settlement of turbulence statistics into a fully developed equilibrium state of the turbulent boundary layer has been carefully monitored, either based on the satisfaction of the von Kármán integral equation or by comparing runs with different inflow turbulence generation techniques. The generated DNS database is …

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Using Supervised Learning Algorithms As A Follow-Up Method In The Search Of Gravitational Waves From Core-Collapse Supernovae, Javier M. Antelis, Marco Cavaglia, Travis Hansen, Manuel D. Morales, Claudia Moreno, Soma Mukherjee, Marek J. Szczepańczyk, Michele Zanolin Apr 2022

Using Supervised Learning Algorithms As A Follow-Up Method In The Search Of Gravitational Waves From Core-Collapse Supernovae, Javier M. Antelis, Marco Cavaglia, Travis Hansen, Manuel D. Morales, Claudia Moreno, Soma Mukherjee, Marek J. Szczepańczyk, Michele Zanolin

Physics Faculty Research & Creative Works

We present a follow-up method based on supervised machine learning (ML) to improve the performance in the search of gravitational wave (GW) bursts from core-collapse supernovae (CCSNe) using the coherent WaveBurst (cWB) pipeline. The ML model discriminates noise from signal events by using a set of reconstruction parameters provided by cWB as features. Detected noise events are discarded yielding a reduction in the false alarm rate (FAR) and the false alarm probability thus enhancing the statistical significance. We tested the proposed method using strain data from the first half of the third observing run of advanced LIGO, and CCSNe GW …

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