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Faculty Publications

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Articles 751 - 780 of 3294

Full-Text Articles in Engineering

Application Of Compositional Data Analysis To Determine The Effects Of Heating Mode, Moisture Status And Plant Species On Pyrolysates, David R. Weise, Thomas H. Fletcher, Mohammad-Saeed Safdari, Elham Amini, Javier Palarea-Albaladejo Jun 2021

Application Of Compositional Data Analysis To Determine The Effects Of Heating Mode, Moisture Status And Plant Species On Pyrolysates, David R. Weise, Thomas H. Fletcher, Mohammad-Saeed Safdari, Elham Amini, Javier Palarea-Albaladejo

Faculty Publications

Pyrolysate gas mixtures are multivariate and relative in nature. Statistical techniques applied to these data generally ignore their relative nature. Published data for permanent gases (CO, CO2, H2, CH4) and tars produced by pyrolysing 15 wildland fuels were reanalysed using compositional data analysis techniques. Mass and mole fractions were compositionally equivalent. Plant species, moisture status and heating mode effects on compositional balances formed from subsets of pyrolysates were tested. Plant species affected the amount of phenol, primary and secondary/tertiary tars relative to permanent gases and relative amounts of single- and multi-ring compounds. Plant moisture status affected the amount of CO …

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Strengthening Of Continuous Reinforced Concrete Deep Beams With Large Openings Using Cfrp Strips, Mohammed Riyadh Khalaf, Ali Hussein Ali Al-Ahmed, Abbas Abdulmajeed Allawi, Ayman El-Zohairy Jun 2021

Strengthening Of Continuous Reinforced Concrete Deep Beams With Large Openings Using Cfrp Strips, Mohammed Riyadh Khalaf, Ali Hussein Ali Al-Ahmed, Abbas Abdulmajeed Allawi, Ayman El-Zohairy

Faculty Publications

To accommodate utilities in buildings, different sizes of openings are provided in the web of reinforced concrete deep beams, which cause reductions in the beam strength and stiffness. This paper aims to investigate experimentally and numerically the effectiveness of using carbon fiber reinforced polymer (CFRP) strips, as a strengthening technique, to externally strengthen reinforced concrete continuous deep beams (RCCDBs) with large openings. The experimental work included testing three RCCDBs under five-point bending. A reference specimen was prepared without openings to explore the reductions in strength and stiffness after providing large openings. Openings were created symmetrically at the center of spans …

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Electromagnetic Wave Propagation For Industry And Biomedical Applications, Fred Lacy Jun 2021

Electromagnetic Wave Propagation For Industry And Biomedical Applications, Fred Lacy

Faculty Publications

Superconductors have a wide array of applications, such as medical imaging, supercomputing, and electric power transmission, but superconducting materials only operate at very cold temperatures. Thus, the quest to engineer room temperature superconductors is currently a hot topic of research. To accomplish this mission, it is important to have a complete understanding of the material properties that are being used to create these superconductors. Understanding the atomic and electromagnetic properties of the prospective materials will provide tremendous insight into the best choice for the materials. Therefore, a theoretical model that incorporates electromagnetic field theory and quantum mechanics principles is utilized …

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Fourth-Order Comprehensive Adjoint Sensitivity Analysis (4th-Casam) Of Response-Coupled Linear Forward/Adjoint Systems: I. Theoretical Framework, Dan Gabriel Cacuci Jun 2021

Fourth-Order Comprehensive Adjoint Sensitivity Analysis (4th-Casam) Of Response-Coupled Linear Forward/Adjoint Systems: I. Theoretical Framework, Dan Gabriel Cacuci

Faculty Publications

The most general quantities of interest (called “responses”) produced by the computational model of a linear physical system can depend on both the forward and adjoint state functions that describe the respective system. This work presents the Fourth-Order Comprehensive Adjoint Sensitivity Analysis Methodology (4th-CASAM) for linear systems, which enables the efficient computation of the exact expressions of the 1st-, 2nd-, 3rd-and 4th-order sensitivities of a generic system response, which can depend on both the forward and adjoint state functions, with respect to all of the parameters underlying the respective forward/adjoint systems. Among the best known such system responses are various …

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Illustrating Important Effects Of Second-Order Sensitivities On Response Uncertainties In Reactor Physics, Dan Gabriel Cacuci Jun 2021

Illustrating Important Effects Of Second-Order Sensitivities On Response Uncertainties In Reactor Physics, Dan Gabriel Cacuci

Faculty Publications

This paper illustrates the relative importance of the largest first- and second-order sensitivities of the leakage response of an OECD/NEA reactor physics benchmark (a polyethylene-reflected plutonium sphere) to the benchmark’s underlying total cross sections. It will be shown that numerous 2nd-order sensitivities of the leakage response with respect to the total cross sections are significantly larger than the largest corresponding 1st-order sensitivities. In particular, the contributions of the 2nd-order sensitivities cause the mean (expected) value of the response to differ appreciably from its computed value and also cause the response distribution to be skewed towards positive values relative to the …

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Reliable Mode Tracking In Gradient-Based Optimization Frameworks With Flutter Constraints, Taylor Mcdonnell, Andrew Ning Jun 2021

Reliable Mode Tracking In Gradient-Based Optimization Frameworks With Flutter Constraints, Taylor Mcdonnell, Andrew Ning

Faculty Publications

In order to construct mode-specific flutter constraints for use in gradient-based multidisciplinary design optimization frameworks, mode tracking must be used to associate the current iteration’s modes with the modes corresponding to each constraint function. Existing mode tracking methods, however, do not provide a method by which to ensure the accuracy of mode associations, making them unsuitable for use in situations where obtaining correct mode associations is critical. To remedy this issue, a new mode tracking method is presented which incorporates backtracking logic in order to maintain an arbitrarily high degree of confidence in mode correlations during gradient-based optimization and/or during …

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Prioritizing Facilities Linked To Corporate Strategic Objectives Using A Fuzzy Model, Devin Depalmer, Steven J. Schuldt, Justin D. Delorit Jun 2021

Prioritizing Facilities Linked To Corporate Strategic Objectives Using A Fuzzy Model, Devin Depalmer, Steven J. Schuldt, Justin D. Delorit

Faculty Publications

Excerpt: Limited facilities operating and modernization budgets require organizations to carefully identify, prioritize and authorize projects to ensure allocated resources align with strategic objectives. Traditional facility prioritization methods using risk matrices can be improved to increase granularity in categorization and avoid mathematical error or human cognitive biases. These limitations restrict the utility of prioritizations and if erroneously used to select projects for funding, they can lead to wasted resources. This paper aims to propose a novel facility prioritization methodology that corrects these assessment design and implementation issues.

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Synthetic Aperture Radar Image Recognition Of Armored Vehicles, Christopher Szul, Torrey J. Wagner, Brent T. Langhals Jun 2021

Synthetic Aperture Radar Image Recognition Of Armored Vehicles, Christopher Szul, Torrey J. Wagner, Brent T. Langhals

Faculty Publications

Synthetic Aperture Radar (SAR) imagery is not affected by weather and allows for day-and-night observations, however it can be difficult to interpret. This work applies classical and neural network machine learning techniques to perform image classification of SAR imagery. The Moving and Stationary Target Acquisition and Recognition dataset from the Air Force Research Laboratory was used, which contained 2,987 total observations of the BMP-2, BTR-70, and T-72 vehicles. Using a 75%/25% train/test split, the classical model achieved an average multi-class image recognition accuracy of 70%, while a convolutional neural network was able to achieve a 97% accuracy with lower model …

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Uniform Strain-Dependent Thermal Conductivity Of Pentagonal And Hexagonal Silicene, Huake Liu, Guangzhao Qin, Ming Hu May 2021

Uniform Strain-Dependent Thermal Conductivity Of Pentagonal And Hexagonal Silicene, Huake Liu, Guangzhao Qin, Ming Hu

Faculty Publications

Two-dimensional (2D) pentagonal monolayer structures have shown promising characteristics and fascinating physical and chemical properties. The disparate strain-dependent thermal conductivity of two-dimensional penta-structures was reported, but the difference between the silicon-based pentagonal and hexagonal structures is barely researched. In this work, based on first-principles calculations, we studied the strain-modulated phonon transport behavior of two 2D pentagonal (penta-SiH and bilayer penta-Si) and one hexagonal silicene structures (H-silicene), of which the penta-SiH and H-silicene mean the structures are hydrogenated for the purpose of thermodynamical stability. We found that the silicon-based pentagonal structure also presented a different strain-dependent thermal conductivity from other pentagonal …

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Resolving Anodic Current And Temperature Distributions In A Polymer Electrolyte Membrane Water Electrolysis Cell Using A Pseudo-Two-Phase Computational Fluid Dynamics Model, J. Lopata, Z. Kang, J. Young, G. Bender, J. W. Weidner, H-S. Cho, Sirivatch Shimpalee May 2021

Resolving Anodic Current And Temperature Distributions In A Polymer Electrolyte Membrane Water Electrolysis Cell Using A Pseudo-Two-Phase Computational Fluid Dynamics Model, J. Lopata, Z. Kang, J. Young, G. Bender, J. W. Weidner, H-S. Cho, Sirivatch Shimpalee

Faculty Publications

Expanding upon our prior experimental work, we constructed a three-dimensional model of a polymer electrolyte membrane water electrolyzer using computational fluid dynamics. We applied the assumption of pseudo-two-phase flow, the flow of two phases with equal velocity. Experimental data were used to obtain parameters and to determine the conditions under which this model was valid. Anodic distributions of current density, temperature, liquid saturation, and relative humidity were obtained at various flow rates. The overall current density and temperature difference from inlet to outlet at the anode agreed strongly with experimental measurements under most circumstances. This verification allowed us to further …

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Pyrolysis Kinetics Of Wildland Vegetation Using Model-Fitting Methods, Ellie Amini, Mohammad-Saeed Safdari, Nathan Johnson Brigham, David R. Weise, Thomas H. Fletcher May 2021

Pyrolysis Kinetics Of Wildland Vegetation Using Model-Fitting Methods, Ellie Amini, Mohammad-Saeed Safdari, Nathan Johnson Brigham, David R. Weise, Thomas H. Fletcher

Faculty Publications

Slow-heating pyrolysis experiments of 14 plant species native to forests in the southern United States were conducted in a TGA to find the kinetic parameters for slow pyrolysis of all live and air-dried plant samples. Kinetic coefficients were determined from the data using model-fitting methods, resulting in single kinetic parameters for the entire pyrolysis process which can be used by wildland fire modelers. The model forms explored here are a simple one-step model and single and multiple reaction distributed activation energy (DAE) models. The mass loss and derivative mass loss data were fitted simultaneously at heating rates of 10, 20, …

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On The Computational Efficiency Of Les And Hybrid Rans-Les Models In Building Aerodynamics, Aly Mousaad Aly, Faiaz Khaled May 2021

On The Computational Efficiency Of Les And Hybrid Rans-Les Models In Building Aerodynamics, Aly Mousaad Aly, Faiaz Khaled

Faculty Publications

Large-eddy simulation (LES) has proven to offer superior accuracy in regards to predicting surface pressures compared to the Reynolds-averaged Navier Stokes (RANS) models. However, the primary impediment is the high computational cost associated with LES. The authors attempt to investigate the computational cost and accuracy by employing different sub-grid scale (SGS) models in LES and hybrid RANS-LES models. One of the prerequisites of accurate pressure estimations is to ensure a horizontally homogeneous empty computational domain. This study aims to compare the computational competence qualitatively and quantitatively using an empty domain in regards to the ability to maintain horizontal homogeneity. The …

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On The Computational Efficiency Of Les And Hybrid Rans-Les Models In Building Aerodynamics, Faiaz Khaled, Aly Mousaad Aly May 2021

On The Computational Efficiency Of Les And Hybrid Rans-Les Models In Building Aerodynamics, Faiaz Khaled, Aly Mousaad Aly

Faculty Publications

No abstract provided.

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Real-Time Motion Tracking Of Cognitive Baxter Robot Based On Differential Inverse Kinematics, Shaobo Li, Xingxing Zhang, Jing Yang, Qiang Bai, Jianjun Hu, Qisong Song, Zhiang Li May 2021

Real-Time Motion Tracking Of Cognitive Baxter Robot Based On Differential Inverse Kinematics, Shaobo Li, Xingxing Zhang, Jing Yang, Qiang Bai, Jianjun Hu, Qisong Song, Zhiang Li

Faculty Publications

The tracking motion of the robot is realized based on a specific robot or relying on an expensive movement acquisition system. It has the problems of complex control procedures, lack of real-time performance, and difficulty in achieving secondary development. We propose a robot real-time tracking control method based on the control principle of differential inverse kinematics, which fuses the position and joint angle information of the robot’s actuators to realize the real-time estimation of the user’s movement during the tracking process. The motion coordinates of each joint of the robot are calculated and the coordinate conversion between man and machine …

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Using Blade Element Momentum Methods With Gradient-Based Design Optimization, Andrew Ning May 2021

Using Blade Element Momentum Methods With Gradient-Based Design Optimization, Andrew Ning

Faculty Publications

Blade element momentum methods are widely used for initial aerodynamic analysis of propellers and wind turbines. A wide variety of correction methods exist, but common to all variations, a pair of residuals are converged to ensure compatibility between the two theories. This paper shows how to rearrange the sequence of calculations reducing to a single residual. This yields the significant advantage that convergence can be guaranteed and to machine precision. Both of these considerations are particularly important for gradient- based optimization where a wide variety of atypical inputs may be explored, and where tight convergence is necessary for accurate derivative …

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Acquiring And Modeling Of Si Solar Cell Transient Response To Pulsed X-Ray, Lei Pan, Praneeth Kandlakunta, Matthew Van Zile, Xuezeng Dai, Jinsong Huang, John W. Mcclory, Lei R. Cao May 2021

Acquiring And Modeling Of Si Solar Cell Transient Response To Pulsed X-Ray, Lei Pan, Praneeth Kandlakunta, Matthew Van Zile, Xuezeng Dai, Jinsong Huang, John W. Mcclory, Lei R. Cao

Faculty Publications

We report on the acquisition and modeling of the transient response of a commercial silicon (Si) solar cell using a benchtop pulsed X-ray source. The solar-cell transient output to the X-ray pulses was acquired under the dark and steady-state light illumination to mimic the practical operation of a solar cell under different light illumination levels. A solar-cell circuit model was created to develop a fundamental understanding of the transient current/voltage response of solar cell at read-out circuit level. The model was validated by a good agreement between the simulation and experimental results. It was found that the solar-cell resistance ( …

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A Critical Review On The Development Of Ionic Liquids-Based Nanofluids As Heat Transfer Fluids For Solar Thermal Energy, Titan C. Paul, Amitav Tikadar, Rajib Mahamud, Azzam S. Salman, A.K.M. Monjur Morshed, Jamil A. Khan Apr 2021

A Critical Review On The Development Of Ionic Liquids-Based Nanofluids As Heat Transfer Fluids For Solar Thermal Energy, Titan C. Paul, Amitav Tikadar, Rajib Mahamud, Azzam S. Salman, A.K.M. Monjur Morshed, Jamil A. Khan

Faculty Publications

In recent years, solar thermal energy (STE) has attracted energy researchers because of its higher efficacy compared to the photovoltaic solar cell. STE is one of the forms of solar energy whereby heat is transferred via a secondary medium called heat transfer fluids (HTFs). Therefore, the overall performance of STE depends on the thermophysical properties and thermal performance of the HTFs. Traditional HTFs suffer from low decomposition temperature, high melting point, and higher vapor pressure. To overcome these limitations, researchers have recently begun working on new HTFs for STE. Ionic liquids (ILs) are considered as a potential candidate for the …

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Editors’ Choice-Examining Performance And Durability Of Anion Exchange Membrane Fuel Cells With Novel Spirocyclic Anion Exchange Membranes, Ami C. Yang-Neyerlin, Samantha Medina, Kelly M. Meek, Derek J. Strasser, Cheng He, Daniel M. Knauss, Mustain E William, Svitlana Pylypenko, Bryan S. Pivovar Apr 2021

Editors’ Choice-Examining Performance And Durability Of Anion Exchange Membrane Fuel Cells With Novel Spirocyclic Anion Exchange Membranes, Ami C. Yang-Neyerlin, Samantha Medina, Kelly M. Meek, Derek J. Strasser, Cheng He, Daniel M. Knauss, Mustain E William, Svitlana Pylypenko, Bryan S. Pivovar

Faculty Publications

A series of spirocyclic copolymer membranes with varying ion exchange capacities (IECs) were investigated to probe the impact of polymer properties on in situ fuel cell performance and stability. In-situ electrochemical tests and post-mortem electron microscopy analysis of cross-sectioned membrane electrode assemblies (MEAs) have been combined with voltage loss breakdown analysis to evaluate the performance and degradation of different MEAs, and to probe the catalyst morphology and electrode structure at different stages of operation. Voltage loss breakdown results show that membrane degradation and kinetic losses played only a minor role in observed performance degradation and that performance losses were primarily …

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Agent-Based Coordinated Control Of Power Electronic Converters In A Microgrid, Maryam Nasri, Hebert L. Ginn Iii, Mehrdad Moallem Apr 2021

Agent-Based Coordinated Control Of Power Electronic Converters In A Microgrid, Maryam Nasri, Hebert L. Ginn Iii, Mehrdad Moallem

Faculty Publications

This paper presents the implementation of an agent-based architecture suitable for the coordination of power electronic converters in stand-alone microgrids. To this end, a publish-subscribe agent architecture was utilized as a distributed microgrid control platform. Over a distributed hash table (DHT) searching overlay, the publish-subscribe architecture was identified based on a numerical analysis as a scalable agent-based technology for the distributed real-time coordination of power converters in microgrids. The developed framework was set up to deploy power-sharing distributed optimization algorithms while keeping a deterministic time period of a few tens of milliseconds for a system with tens of converters and …

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Characterization Of A Boron-Loaded Deuterated Liquid Scintillator For Fast And Thermal Neutron Detection, Bryan V. Egner, Michael Febbraro, James E. Bevins Apr 2021

Characterization Of A Boron-Loaded Deuterated Liquid Scintillator For Fast And Thermal Neutron Detection, Bryan V. Egner, Michael Febbraro, James E. Bevins

Faculty Publications

The preparation and characterization of novel boron-loaded deuterated liquid scintillators (BLDLS) are presented for the first time to investigate the performance of a detector sensitive to both fast and thermal neutrons intended for future neutron spectroscopy measurements. Three deuterated toluene-based scintillation cocktails were produced, one without boron, one loaded with ortho-carborane (natural boron isotopic abundance), and one with 96 wt% 10B enriched ortho-carborane. General optical and material properties were analyzed to include the composition, density, index of refraction, photoluminescence emission spectra, and absorbance spectra in addition to the relative light yield, resolution, relative efficiency, and pulse-shape-discrimination performance for all three …

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Mlatticeabc: Generic Lattice Constant Prediction Of Crystal Materials Using Machine Learning, Yuxin Li, Wenhui Yang, Rongzhi Dong, Jianjun Hu Apr 2021

Mlatticeabc: Generic Lattice Constant Prediction Of Crystal Materials Using Machine Learning, Yuxin Li, Wenhui Yang, Rongzhi Dong, Jianjun Hu

Faculty Publications

Lattice constants such as unit cell edge lengths and plane angles are important parameters of the periodic structures of crystal materials. Predicting crystal lattice constants has wide applications in crystal structure prediction and materials property prediction. Previous work has used machine learning models such as neural networks and support vector machines combined with composition features for lattice constant prediction and has achieved a maximum performance for cubic structures with an average coefficient of determination (R2) of 0.82. Other models tailored for special materials family of a fixed form such as ABX3 perovskites can achieve much higher performance due …

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High In-Plane Thermal Conductivity Of Aluminum Nitride Thin Films, Md Shafkat Bin Hoque, Yee Rui Koh, Jeffrey L. Braun, Abdullah Mamun, Zeyu Liu, Kenny Huynh, Micheal E. Liao, Kamal Hussain, Zhe Cheng, Eric R. Hoglund, David H. Olson, John A. Tomko, Kiumars Aryana, Roisul Galib, John T. Gaskins, Mirza Mohammad Mahbube Elahi, Zayd C. Leseman, James M. Howe, Tengfei Luo, Samuel Graham, Mark S. Goorsky, Asif Khan, Patrick E. Hopkins Apr 2021

High In-Plane Thermal Conductivity Of Aluminum Nitride Thin Films, Md Shafkat Bin Hoque, Yee Rui Koh, Jeffrey L. Braun, Abdullah Mamun, Zeyu Liu, Kenny Huynh, Micheal E. Liao, Kamal Hussain, Zhe Cheng, Eric R. Hoglund, David H. Olson, John A. Tomko, Kiumars Aryana, Roisul Galib, John T. Gaskins, Mirza Mohammad Mahbube Elahi, Zayd C. Leseman, James M. Howe, Tengfei Luo, Samuel Graham, Mark S. Goorsky, Asif Khan, Patrick E. Hopkins

Faculty Publications

High thermal conductivity materials show promise for thermal mitigation and heat removal in devices. However, shrinking the length scales of these materials often leads to significant reductions in thermal conductivities, thus invalidating their applicability to functional devices. In this work, we report on high in-plane thermal conductivities of 3.05, 3.75, and 6 μm thick aluminum nitride (AlN) films measured via steady-state thermoreflectance. At room temperature, the AlN films possess an in-plane thermal conductivity of ∼260 ± 40 W m–1 K–1, one of the highest reported to date for any thin film material of equivalent thickness. At low temperatures, the in-plane …

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Impact Of Hurricane Michael (2018) On Local Vertical Total Electron Content, Joanna E.S. Williams, Robert C. Tournay, H. Rose Tseng, Daniel J. Emmons Ii, Omar A. Nava Apr 2021

Impact Of Hurricane Michael (2018) On Local Vertical Total Electron Content, Joanna E.S. Williams, Robert C. Tournay, H. Rose Tseng, Daniel J. Emmons Ii, Omar A. Nava

Faculty Publications

An analysis of vertical total electron content (TEC) estimates from the MIT Madrigal database is performed for the regions surrounding the eye of Hurricane Michael (2018). Absolute and detrended TEC values show a noticeable increase during the tropical cyclone (TC) relative to fluctuations at the same locations prior to the storm. Direct comparisons of TEC perturbation magnitudes to the number of lightning flashes in latitude-longitude boxes surrounding the eye of Hurricane Michael for each 5 min period of 10 October 2018 showed no visible trends. A similar comparison of the vertical TEC fluctuations with respect to the rainfall rates showed …

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Unified Multi-Objective Genetic Algorithm For Energy Efficient Job Shop Scheduling, Hongjong Wei, Shaobo Li, Huageng Quan, Dacheng Liu, Shu Rao, Chuanjiang Li, Jianjun Hu Apr 2021

Unified Multi-Objective Genetic Algorithm For Energy Efficient Job Shop Scheduling, Hongjong Wei, Shaobo Li, Huageng Quan, Dacheng Liu, Shu Rao, Chuanjiang Li, Jianjun Hu

Faculty Publications

In recent years, people have paid more and more attention to traditional manufacturing’s environmental impact, especially in terms of energy consumption and related emissions of carbon dioxide. Except for adopting new equipment, production scheduling could play an important role in reducing the total energy consumption of a manufacturing plant. Machine tools waste a considerable amount of energy because of their underutilization. Consequently, energy saving can be achieved by switching machines to standby or off when they lay idle for a comparatively long period. Herein, we first introduce the objectives of minimizing non-processing energy consumption, total weighted tardiness and earliness, and …

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Hybrid Lattice Boltzmann Agglomeration Method For Modeling Transport Phenomena In Polymer Electrolyte Membrane Fuel Cells, P. Satjaritanun, F. C. Cetinbas, S. Hirano, I. V. Zenyuk, R. K. Ahluwalia, Sirivatch Shimpalee Apr 2021

Hybrid Lattice Boltzmann Agglomeration Method For Modeling Transport Phenomena In Polymer Electrolyte Membrane Fuel Cells, P. Satjaritanun, F. C. Cetinbas, S. Hirano, I. V. Zenyuk, R. K. Ahluwalia, Sirivatch Shimpalee

Faculty Publications

The Hybrid Lattice Boltzmann Agglomeration Method (HLBAM) was employed to model transport phenomena and electrochemical kinetics in the catalyst layer of a polymer electrolyte membrane fuel cell (PEMFC). This work showed the advantages of using a direct modeling-based HLBAM approach, which incorporates the detailed structure of catalyst layers from X-ray computed tomography as well as local transport variables related characteristics and effective properties from the hybrid catalyst microstructure. The local transport variables and effective properties from the hybrid catalyst model were used to simulate the electrochemical kinetics inside the detailed structure of the catalyst layer. HLBAM can predict the distribution …

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Covid-19: Insights Into Virus-Receptor Interactions, Azadeh Sepahvandi, Maryann Ghaffari, Amir Hossein Bahmanpour, Fathollah Moztarzadeh, Payam Zarrintaj, Hasan Uludağ, Masoud Mozafari Apr 2021

Covid-19: Insights Into Virus-Receptor Interactions, Azadeh Sepahvandi, Maryann Ghaffari, Amir Hossein Bahmanpour, Fathollah Moztarzadeh, Payam Zarrintaj, Hasan Uludağ, Masoud Mozafari

Faculty Publications

The recent outbreak of Coronavirus Disease 2019 (COVID-19) calls for rapid mobilization of scientists to probe and explore solutions to this deadly disease. A limited understanding of the high transmissibility of SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) relative to other coronavirus strains guides a deeper investigation into the virus/receptor interactions. The cutting-edge studies in thermodynamic and kinetic properties of interactions such as protein-protein interplays have been reviewed in many modeling and analysis studies. Highlighting the thermodynamic assessments of biological interactions and emphasizing the boosted transmissibility of SARS-CoV-2 despite its high similarity in structure and sequence with other coronavirus strains …

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Effect Of Defects Part Ii: Multiscale Effect Of Microvoids, Orientation Of Rivet Holes On The Damage Propagation, And Ultimate Failure Strength Of Composites, Vahid Tavaf, Mohammadsadegh Saadatzi, Sourav Banerjee Apr 2021

Effect Of Defects Part Ii: Multiscale Effect Of Microvoids, Orientation Of Rivet Holes On The Damage Propagation, And Ultimate Failure Strength Of Composites, Vahid Tavaf, Mohammadsadegh Saadatzi, Sourav Banerjee

Faculty Publications

Material properties at the vicinity of the cut-outs in composites are not entirely defect-free. The nteraction of multiple cutouts like rivet holes, the repercussion of their configuration on crack propagation, and ultimate strength were predicted using Peridynamic method and the results are reported in this article. The effect of microscale defects at the vicinity of the cutouts on macroscale damage propagation were shown to have quantifiable manifestation. This study focused on two to four holes in unidirectional composite plates with 0°, 45°, and 90° fiber directions, while the vicinity of a hole was considered degraded. Numerical results were validated using …

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Identification Of Active Surface Species In Molten Carbonates Using In Situ Raman Spectroscopy, Peng Zhang, Tao Wu, Kevin Huang Apr 2021

Identification Of Active Surface Species In Molten Carbonates Using In Situ Raman Spectroscopy, Peng Zhang, Tao Wu, Kevin Huang

Faculty Publications

Here we report the results of a study on active surface species of a pristine and modified (Li-Na)2CO3 eutectic using in situ Raman spectroscopy technique. The effects of gas compositions, temperature, time, and alkaline earth have been systematically studied. The species of CO42–, HCO4–, and C2O52– are identified as the three major active species on the surface of (Li-Na)2CO3 eutectic by a combined Raman spectroscopy and theoretical density functional theory calculations. The results further reveal that CO42–, HCO4–, …

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Hydrothermal Synthesis And Structural Investigation Of A Crystalline Uranyl Borosilicate, Kristen A. Pace, Vladislav V. Klepov, Mark D. Smith, Travis Williams, Gregory Morrison, Jochen A. Lauterbach, Scott T. Misture, Hans Conrad Zur Loye Apr 2021

Hydrothermal Synthesis And Structural Investigation Of A Crystalline Uranyl Borosilicate, Kristen A. Pace, Vladislav V. Klepov, Mark D. Smith, Travis Williams, Gregory Morrison, Jochen A. Lauterbach, Scott T. Misture, Hans Conrad Zur Loye

Faculty Publications

The relevance of multidimensional and porous crystalline materials to nuclear waste reme-diation and storage applications has motivated exploratory research focused on materials discovery of compounds, such as actinide mixed-oxoanion phases, which exhibit rich structural chemistry. The novel phase K1.8 Na1.2 [(UO2)BSi4 O12 ] has been synthesized using hydrothermal methods, rep-resenting the first example of a uranyl borosilicate. The three-dimensional structure crystallizes in the orthorhombic space group Cmce with lattice parameters a = 15.5471(19) Å, b = 14.3403(17) Å, c = 11.7315(15) Å, and V = 2615.5(6) Å3, and is composed of UO6 octahedra linked by [BSi4 O12 ]5− chains to …

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High-Order Wave-Damage Interaction Coefficients (Wdic) Extracted Through Modal Decomposition, Hanfei Mei, Victor Giurgiutiu Apr 2021

High-Order Wave-Damage Interaction Coefficients (Wdic) Extracted Through Modal Decomposition, Hanfei Mei, Victor Giurgiutiu

Faculty Publications

This paper presents a new technique for the extraction of high-order wave-damage interaction coefficients (WDIC) through modal decomposition. The frequency and direction dependent complex-valued WDIC are used to model the scattering and mode conversion phenomena of guided wave interaction with damage. These coefficients are extracted from the harmonic analysis of local finite element model (FEM) mesh with non-reflective boundaries (NRB) and they are capable of describing the amplitude and phase of the scattered waves as a function of frequency and direction. To extract the WDIC of each wave mode, all the possible propagating wave modes are considered to be scattered …

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