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Articles 2521 - 2550 of 33019

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A Spike-Shaped Anchorage For Steel Reinforced Polymer (Srp)-Strengthened Concrete Structures, Xingxing Zou, Keenan L. Mcburney, Lesley H. Sneed Jul 2023

A Spike-Shaped Anchorage For Steel Reinforced Polymer (Srp)-Strengthened Concrete Structures, Xingxing Zou, Keenan L. Mcburney, Lesley H. Sneed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Steel reinforced polymer (SRP) composite has recently emerged as an effective and economical solution for strengthening of reinforced concrete (RC) structures. Premature debonding failure of unanchored SRP at low load levels generally governs the performance of RC structures strengthened with externally bonded SRP. Therefore, a novel yet simple spike-shaped anchorage system was proposed in this study to prevent the debonding failure of SRP and to improve the interfacial shear capacity. Experimental investigation through single-lap shear tests of SRP-concrete joints showed that the anchorage system changed the failure mode from composite debonding to fiber rupture. In addition, the anchorage system substantially …

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Understanding Formation And Roles Of Niᴵᴵ Aryl Amido And Niiii Aryl Amido Intermediates In Ni-Catalyzed Electrochemical Aryl Amination Reactions, Jian Luo, Michael T. Davenport, Chad Callister, Shelley D. Minteer, Daniel H. Ess, T. Leo Liu Jul 2023

Understanding Formation And Roles Of Niᴵᴵ Aryl Amido And Niiii Aryl Amido Intermediates In Ni-Catalyzed Electrochemical Aryl Amination Reactions, Jian Luo, Michael T. Davenport, Chad Callister, Shelley D. Minteer, Daniel H. Ess, T. Leo Liu

Chemistry Faculty Research & Creative Works

Ni-catalyzed electrochemical aryl amination (e-amination) is an attractive, emerging approach to building C-N bonds. Here, we report in-depth experimental and computational studies that examined the mechanism of Ni-catalyzed e-amination reactions. Key NiII-amine dibromide and NiII aryl amido intermediates were chemically synthesized and characterized. the combination of experiments and DFT calculations suggest (1) there is coordination of an amine to the NiII catalyst before the cathodic reduction and oxidative addition steps, (2) a stable NiII aryl amido intermediate is produced from the cathodic half-reaction, a critical step in controlling the selectivity between cross-coupling and undesired homo-coupling reaction pathways, (3) the diazabicycloundecene …

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In-Situ Lock-In Thermographic Measurement Of Powder Layer Thermal Diffusivity And Thickness In Laser Powder Bed Fusion, Tao Liu, Edward C. Kinzel, Ming-Chuan Leu Jul 2023

In-Situ Lock-In Thermographic Measurement Of Powder Layer Thermal Diffusivity And Thickness In Laser Powder Bed Fusion, Tao Liu, Edward C. Kinzel, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The thermal transport properties of the powder layer play a crucial role in the process of laser powder bed fusion (LPBF). This paper introduces an in-situ measurement method utilizing active lock-in infrared thermography (LIT) to determine the thermal diffusivity and thickness of the powder layer. The proposed method exhibits great potential for accurate powder property and thickness measurements and real-time process monitoring. In this lock-in thermographic technique, the LPBF laser beam is directed through an optical diffuser and modulated into a square thermal wave. This thermal wave serves as an active heat source to heat the surface of the powder …

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A Natural Organic Artificial Synaptic Device Made From A Honey And Carbon Nanotube Admixture For Neuromorphic Computing, Md Mehedi Hasan Tanim, Zoe Templin, Kaleb Hood, Jun Jiao, Feng Zhao Jul 2023

A Natural Organic Artificial Synaptic Device Made From A Honey And Carbon Nanotube Admixture For Neuromorphic Computing, Md Mehedi Hasan Tanim, Zoe Templin, Kaleb Hood, Jun Jiao, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

Artificial synaptic devices are the essential hardware component in emerging neuromorphic computing systems by mimicking biological synapse and brain functions. When made from natural organic materials such as protein and carbohydrate, they have potential to improve sustainability and reduce electronic waste by enabling environmentally friendly disposal. In this paper, a new natural organic memristor based artificial synaptic device is reported with the memristive film processed by a honey and carbon nanotube (CNT) admixture, that is, honey-CNT memristor. Optical microscopy, scanning electron microscopy, and micro-Raman spectroscopy are employed to analyze the morphology and chemical structure of the honey-CNT film. The device …

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Experiential Learning And Exposure To Professional Experience In Civil Engineering Education, Sanjay Tewari Jul 2023

Experiential Learning And Exposure To Professional Experience In Civil Engineering Education, Sanjay Tewari

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Experiential learning is increasingly recognized as a crucial component of modern education, especially in fields like civil engineering, where practical skills and real-world exposure are paramount. This paper explores the various avenues through which civil engineering education can offer professional exposure and experiential learning opportunities. By analyzing the impact of senior seminars, internships, co-ops, undergraduate research, study abroad programs, service learning, student design teams, leadership positions, and involvement in technical and professional student organizations, this paper aims to underscore the importance of these approaches in shaping well-rounded and industry-ready civil engineers.

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Generative Relevance Feedback With Large Language Models, Iain Mackie, Shubham Chatterjee, Jeffrey Dalton Jul 2023

Generative Relevance Feedback With Large Language Models, Iain Mackie, Shubham Chatterjee, Jeffrey Dalton

Computer Science Faculty Research & Creative Works

Current query expansion models use pseudo-relevance feedback to improve first-pass retrieval effectiveness; however, this fails when the initial results are not relevant. Instead of building a language model from retrieved results, we propose Generative Relevance Feedback (GRF) that builds probabilistic feedback models from long-form text generated from Large Language Models. We study the effective methods for generating text by varying the zero-shot generation subtasks: queries, entities, facts, news articles, documents, and essays. We evaluate GRF on document retrieval benchmarks covering a diverse set of queries and document collections, and the results show that GRF methods significantly outperform previous PRF methods. …

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Neuro-Symbolic Representations For Information Retrieval, Laura Dietz, Hannah Bast, Shubham Chatterjee, Jeff Dalton, Jian Yun Nie, Rodrigo Nogueira Jul 2023

Neuro-Symbolic Representations For Information Retrieval, Laura Dietz, Hannah Bast, Shubham Chatterjee, Jeff Dalton, Jian Yun Nie, Rodrigo Nogueira

Computer Science Faculty Research & Creative Works

This tutorial will provide an overview of recent advances on neuro-symbolic approaches for information retrieval. A decade ago, knowledge graphs and semantic annotations technology led to active research on how to best leverage symbolic knowledge. At the same time, neural methods have demonstrated to be versatile and highly effective. From a neural network perspective, the same representation approach can service document ranking or knowledge graph reasoning. End-to-end training allows to optimize complex methods for downstream tasks. We are at the point where both the symbolic and the neural research advances are coalescing into neuro-symbolic approaches. The underlying research questions are …

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Detecting Mental Distresses Using Social Behavior Analysis In The Context Of Covid-19: A Survey, Sahraoui Dhelim, Liming Chen, Sajal K. Das, Huansheng Ning, Chris Nugent, Gerard Leavey, Dirk Pesch, Eleanor Bantry-White, Devin Michael Burns Jul 2023

Detecting Mental Distresses Using Social Behavior Analysis In The Context Of Covid-19: A Survey, Sahraoui Dhelim, Liming Chen, Sajal K. Das, Huansheng Ning, Chris Nugent, Gerard Leavey, Dirk Pesch, Eleanor Bantry-White, Devin Michael Burns

Computer Science Faculty Research & Creative Works

Online social media provides a channel for monitoring people's social behaviors from which to infer and detect their mental distresses. During the COVID-19 pandemic, online social networks were increasingly used to express opinions, views, and moods due to the restrictions on physical activities and in-person meetings, leading to a significant amount of diverse user-generated social media content. This offers a unique opportunity to examine how COVID-19 changed global behaviors regarding its ramifications on mental well-being. In this article, we surveyed the literature on social media analysis for the detection of mental distress, with a special emphasis on the studies published …

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Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos Jul 2023

Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

The tripodal compounds [(TMG3trphen)MII-solv](PF6)2 (M = Mn, Fe, Co; solv = MeCN, DMF) and bipodal analogues [(TMG2biphen)MII(NCMe)x](PF6)2 (x = 3 for Mn, Fe; x = 2 for Co) and [(TMG2biphen)MIICl2] have been synthesized with ligands that feature a triaryl- or diarylmethyl-amine framework and superbasic tetramethylguanidinyl residues (TMG). The dicationic M(II) sites mediate catalytic nitrene-transfer reactions between the imidoiodinane PhI═NTs (Ts = tosyl) and a panel of styrenes in MeCN to afford aziridines and low yields of imidazolines (upon …

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Calibration Of The Johnson–Cook Model At High Temperatures For An Ultra-High Strength Crnimov Steel, Mario F. Buchely, S. Chakraborty, V. Athavale, Laura Bartlett, Ronald J. O'Malley, D. Field, K. Limmer, K. Sebeck Jul 2023

Calibration Of The Johnson–Cook Model At High Temperatures For An Ultra-High Strength Crnimov Steel, Mario F. Buchely, S. Chakraborty, V. Athavale, Laura Bartlett, Ronald J. O'Malley, D. Field, K. Limmer, K. Sebeck

Materials Science and Engineering Faculty Research & Creative Works

This paper presents a study on the thermo-mechanical behavior of an ultra-high strength CrNiMoV steel at high temperatures and medium strain rates through hot tensile tests. The material was examined in two conditions: as-cast/heat-treated (AC/HT) and as-rolled (AR). Tensile tests were conducted at temperatures of 800,900,1000,1100, and 1200°C, and strain rates of 0.1,1, and 10s−1. Inclusion and porosity analysis was also performed on the tensile specimens. The results revealed that the flow stress decreased by approximately 70% on average from 800°C to 1200°C, while increasing by approximately 32% on average from 0.1s−1 to 10s−1 in strain rate. The elongation exhibited …

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Effect Of Internal Curing And Shrinkage-Mitigating Materials On Microstructural Characteristics Of Fiber-Reinforced Mortar, Kamran Aghaee, Kamal Khayat Jul 2023

Effect Of Internal Curing And Shrinkage-Mitigating Materials On Microstructural Characteristics Of Fiber-Reinforced Mortar, Kamran Aghaee, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Internal curing (IC) and other shrinkage mitigating materials are employed to reduce shrinkage and risk of cracking. This study investigates the efficiency of individual versus combined use of IC and shrinkage mitigating materials on key characteristics of fiber-reinforced mortar (FRM). The investigated mixtures include a 25% pre-saturated lightweight sand (LWS) that is added individually and combined with 10% CaO-based expansive agent (EA) and 2% shrinkage reducing admixture (SRA). This elucidates the synergistic effect of high content IC and EA/SRA on macro- and micro-mechanical characteristics of FRM, especially at the interface of the matrix with fibers. Mechanical properties, microstructural characteristics, and …

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A Strong And Ductile Cobalt-Free Solid-Solution Fe30ni30mn30cr10 Multi-Principal Element Alloy From Hot Rolling, Hans Pommerenke, Jiaqi Duan, Nathan Curtis, Victor Delibera, Adam Bratten, Andrew Hoffman, Mario F. Buchely, Ronald J. O'Malley, Haiming Wen Jul 2023

A Strong And Ductile Cobalt-Free Solid-Solution Fe30ni30mn30cr10 Multi-Principal Element Alloy From Hot Rolling, Hans Pommerenke, Jiaqi Duan, Nathan Curtis, Victor Delibera, Adam Bratten, Andrew Hoffman, Mario F. Buchely, Ronald J. O'Malley, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Most of the Face-Centered Cubic (FCC) Multi-Principal Element Alloys (MPEAs) Developed Thus Far Contain Cobalt. for Many Applications, it is Either required or Beneficial to Avoid Cobalt, Since Cobalt Has Long-Term Activation Issue (For Nuclear Applications), is Expensive, and is Considered a Critical Material. in Addition, FCC Structured Solid-Solution MPEAs Tend to Have Relatively Low Strength. a FCC Solid-Solution Fe30Ni30Mn30Cr10 (At %) MPEA Was Fabricated Via Arc Melting, Followed by Homogenization at 1100 °C for 12 H. the Alloy Was Hot Rolled at 1100 °C with a Total Reduction of Up to 97 %. the Microstructure Was Characterized and Mechanical …

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A Strong And Ductile Cobalt-Free Solid-Solution Fe30ni30mn30cr10 Multi-Principal Element Alloy From Hot Rolling, Hans Pommerenke, Jiaqi Duan, Nathan Curtis, Victor Delibera, Adam Bratten, Andrew Hoffman, Mario Buchely, Ronald O'Malley, Haiming Wen Jul 2023

A Strong And Ductile Cobalt-Free Solid-Solution Fe30ni30mn30cr10 Multi-Principal Element Alloy From Hot Rolling, Hans Pommerenke, Jiaqi Duan, Nathan Curtis, Victor Delibera, Adam Bratten, Andrew Hoffman, Mario Buchely, Ronald O'Malley, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Most of the face-centered cubic (FCC) multi-principal element alloys (MPEAs) developed thus far contain cobalt. for many applications, it is either required or beneficial to avoid cobalt, since cobalt has long-term activation issue (for nuclear applications), is expensive, and is considered a critical material. in addition, FCC structured solid-solution MPEAs tend to have relatively low strength. an FCC solid-solution Fe30Ni30Mn30Cr10 (at %) MPEA was fabricated via arc melting, followed by homogenization at 1100 °C for 12 h. the alloy was hot rolled at 1100 °C with a total reduction of up to 97 %. the microstructure was characterized, and mechanical …

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Viscoelastic Properties Of Fresh Cement Paste: Measuring Procedures And Influencing Parameters, Ammar Yahia, Arnaud Perrot, Dimitri Feys, Kamal Khayat, Mohammed Sonebi, Shiho Kawashima, Wolfram Schmidt Jul 2023

Viscoelastic Properties Of Fresh Cement Paste: Measuring Procedures And Influencing Parameters, Ammar Yahia, Arnaud Perrot, Dimitri Feys, Kamal Khayat, Mohammed Sonebi, Shiho Kawashima, Wolfram Schmidt

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fresh cement pastes behave as viscoelastic materials below the flow onset. The measurements of viscoelastic properties of fresh cement paste provide valuable insight into the dispersion of solid particles as well as the hydration kinetics at early age and its influence on the structural evolution and solidification behavior at quasi-static conditions. Monitoring the development of viscoelastic properties of fresh cement paste using dynamic oscillatory shear measurements can also elucidate the working mechanisms of chemical admixtures. These properties are efficient indicators to guide mixture proportion design and are necessary to understand the rheology and stability of concrete. In this paper, the …

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High-Temperature Phonon-Assisted Upconversion Photoluminescence Of Monolayer Wse2, Fengkai Meng, Xiaodong Yang, Jie Gao Jul 2023

High-Temperature Phonon-Assisted Upconversion Photoluminescence Of Monolayer Wse2, Fengkai Meng, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Phonon-assisted up conversion photoluminescence (UPL) is an anti-Stokes process emitting photons of energy higher than the excitation photons, with up conversion energy gain provided by optical phonons. Atomically thin transition metal dichalcogenides provide a promising platform for exploring the phonon-assisted UPL process due to their strong phonon-exciton interactions. Here, high-temperature phonon-assisted UPL process in monolayer WSe2 is investigated, aiming to understand the role of phonon population and the number of phonons involved in the UPL process at elevated temperatures. It is demonstrated that the integrated intensity of UPL emission significantly increases by two orders of magnitude as the temperature rises …

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Numerical Modeling Of Rock Blocks With Nonpersistent Rough Joints Subjected To Uniaxial Compressive And Shear Loadings, Mostafa Asadizadeh, Mahdi Moosavi, Mohammad Farouq Hossaini, Ahmadreza Hedayat, Taghi Sherizadeh, Hossein Masoumi Jul 2023

Numerical Modeling Of Rock Blocks With Nonpersistent Rough Joints Subjected To Uniaxial Compressive And Shear Loadings, Mostafa Asadizadeh, Mahdi Moosavi, Mohammad Farouq Hossaini, Ahmadreza Hedayat, Taghi Sherizadeh, Hossein Masoumi

Mining Engineering Faculty Research & Creative Works

Characterizing the mechanical behavior of jointed rocks is important to understand the behavior of structures in rock masses. Jointed rocks can be composed of persistent and nonpersistent joints where the impact of nonpersistent joints requires careful consideration for an accurate rock mass mechanical characterization. Most previous investigations into nonpersistent jointed rocks focused on joints with smooth surfaces, and a few experimental studies focused on nonpersistent rough joints and nothing specific has been reported numerically. Therefore, this study investigated several synthetic jointed rocks with nonpersistent rough joints numerically under uniaxial compressive and shear loadings. The PFC2D-based synthetic rock mass (SRM) approach …

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A Non-Line-Of-Sight Mitigation Method For Indoor Ultra-Wideband Localization With Multiple Walls, Mengyao Dong, Yihong Qi, Xianbin Wang, Yiming Liu Jul 2023

A Non-Line-Of-Sight Mitigation Method For Indoor Ultra-Wideband Localization With Multiple Walls, Mengyao Dong, Yihong Qi, Xianbin Wang, Yiming Liu

Electrical and Computer Engineering Faculty Research & Creative Works

Ultra-wideband (UWB) ranging techniques can provide accurate distance measurement under line-of-sight (LOS) conditions. However, various walls and obstacles in indoor non-LOS (NLOS) environments, which obstruct the direct propagation of UWB signals, can generate significant ranging errors. Due to the complex through-wall UWB signal propagation, most conventional studies simplify the ranging error model by assuming that the incidence angle is zero or the relative permittivity's for different walls are the same to improve the through-wall UWB localization performance. Considering walls are different in realistic settings, this article presents a through-multiple-wall NLOS mitigation method for UWB indoor positioning. First, spatial geometric equilibrium …

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Detection Of Critical Cancer Cells In Human Organs Using Dual Demodulation Photonic Crystal Fiber: Numerical Study, Farhan Mumtaz Jul 2023

Detection Of Critical Cancer Cells In Human Organs Using Dual Demodulation Photonic Crystal Fiber: Numerical Study, Farhan Mumtaz

Electrical and Computer Engineering Faculty Research & Creative Works

This study reports a novel approach for early detection of malignant cancer cells in human organs using a birefringent photonic crystal fiber (PCF)-based optical sensor with dual demodulation. The PCF injects light into the middle hole, enhancing the radiated evanescent field. Analytes injected through the core cause a wavelength shift, measured by peak or dip shift. The proposed sensor has an optimal sensitivity of −7,940 nm/RIU, −8,265 nm/RIU, −9,747 nm/RIU, −9,006 nm/RIU, and −8,994 nm/RIU by peak shift and −8,745 nm/RIU, −10,728 nm/RIU, −8,721 nm/RIU, −10,113 nm/RIU, and −11,150 nm/RIU by dip shift for CRT-(Cervical tissue), BLD-(Blood), ADG-(Adrenal gland), BRT-(Breast) …

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New Methodology For Benchmarking Hydrodynamics In Bubble Columns With Intense Internals Using The Radioactive Particle Tracking (Rpt) Technique, Omar J. Farid, Alexandre França Velo, Binbin Qi, Muthanna H. Al-Dahhan Jul 2023

New Methodology For Benchmarking Hydrodynamics In Bubble Columns With Intense Internals Using The Radioactive Particle Tracking (Rpt) Technique, Omar J. Farid, Alexandre França Velo, Binbin Qi, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new methodology for implementing radioactive particle tracking (RPT) in bubble columns with intense vertical rod internals was developed and implemented to investigate the effect of dense internals on hydrodynamics. The methodology utilizes a hybrid of Monte Carlo N-Particle (MCNP) simulation and an automated RPT calibration device to generate a large number of calibration points for accurate reconstruction of the instantaneous positions of radioactive particles using a similarity algorithm. Measurements were conducted in a 6-inch (15.24 cm) Plexiglas column using an air–water system at a superficial gas velocity of 40 cm/s. Vertical Plexiglas rods 0.5 in (1.27 cm) in diameter …

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Beyond A Vision For The Future: Tangible Steps To Engage Diverse Participants In Inclusive Field Experiences, Robin M. Verble, Corinne L. Richards-Zawacki, Vanessa K.H. Young Jul 2023

Beyond A Vision For The Future: Tangible Steps To Engage Diverse Participants In Inclusive Field Experiences, Robin M. Verble, Corinne L. Richards-Zawacki, Vanessa K.H. Young

Biological Sciences Faculty Research & Creative Works

Synopsis Recent strides toward improving diversity, equity, and inclusion (DEI) in field biology present a unique opportunity for transdisciplinary exploration of the impacts and state of a topic that has remained hereto largely underexplored and under-discussed in the academic setting. Within current literature, themes of racial and gender inequity, power imbalances, unsafe environments, and underdeveloped infrastructure and resources are widespread. Thus, we organized a symposium that addressed these compelling issues in field biology DEI through a multitude of experiential and academic lenses. This article will orient the reader to the special issue and offer summative goals and outcomes of the …

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Engineering Heterogeneous Nucleation During Solidification Of Multiphase Cast Alloys: An Overview, Simon (Semen) N. Lekakh, Jingjing Qing Jul 2023

Engineering Heterogeneous Nucleation During Solidification Of Multiphase Cast Alloys: An Overview, Simon (Semen) N. Lekakh, Jingjing Qing

Materials Science and Engineering Faculty Research & Creative Works

The theory of heterogeneous nucleation was initially developed as a part of condensed matter physics, and later it was used as an important engineering tool to design metallurgical processes. This success has led to wide applications of the theory in metallurgical practice. For example, engineering heterogeneous nucleation in ductile iron has been used to reduce shrinkage defects, suppress cementite formation, and modify the size and shape of microstructural constituencies. This demonstrates how theoretical knowledge could benefit industry practice. This overview aims to summarize the authors' published studies in co-authorship with colleagues and students, which covers different aspects of engineering heterogeneous …

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Kinetic Particle Simulations Of Plasma Charging At Lunar Craters Under Severe Conditions, David Lund, Xiaoming He, Daoru Frank Han Jul 2023

Kinetic Particle Simulations Of Plasma Charging At Lunar Craters Under Severe Conditions, David Lund, Xiaoming He, Daoru Frank Han

Mathematics and Statistics Faculty Research & Creative Works

This paper presents fully kinetic particle simulations of plasma charging at lunar craters with the presence of lunar lander modules using the recently developed Parallel Immersed-Finite-Element Particle-in-Cell (PIFE-PIC) code. The computation model explicitly includes the lunar regolith layer on top of the lunar bedrock, taking into account the regolith layer thickness and permittivity as well as the lunar lander module in the simulation domain, resolving a nontrivial surface terrain or lunar lander configuration. Simulations were carried out to study the lunar surface and lunar lander module charging near craters at the lunar terminator region under mean and severe plasma environments. …

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Don’T Touch That Dial: Psychological Reactance, Transparency, And User Acceptance Of Smart Thermostat Setting Changes, Matthew Heatherly, Denise A. Baker, Casey I. Canfield Jul 2023

Don’T Touch That Dial: Psychological Reactance, Transparency, And User Acceptance Of Smart Thermostat Setting Changes, Matthew Heatherly, Denise A. Baker, Casey I. Canfield

Psychological Science Faculty Research & Creative Works

Automation inherently removes a certain amount of user control. If perceived as a loss of freedom, users may experience psychological reactance, which is a motivational state that can lead a person to engage in behaviors to reassert their freedom. In an online experiment, participants set up and communicated with a hypothetical smart thermostat. Participants read notifications about a change in the thermostat's setting. Phrasing of notifications was altered across three dimensions: strength of authoritative language, deviation of temperature change from preferences, and whether or not the reason for the change was transparent. Authoritative language, temperatures outside the user's preferences, and …

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Logarithmic Terms In Atom-Surface Potentials: Limited Applicability Of Rational Approximations For Intermediate Distance, Ulrich D. Jentschura, C. Moore Jul 2023

Logarithmic Terms In Atom-Surface Potentials: Limited Applicability Of Rational Approximations For Intermediate Distance, Ulrich D. Jentschura, C. Moore

Physics Faculty Research & Creative Works

It is usually assumed that interaction potentials, in general, and atom-surface potential, in particular, can be expressed in terms of an expansion involving integer powers of the distance between the two interacting objects. Here, we show that, in the short-range expansion of the interaction potential of a neutral atom and a dielectric surface, logarithms of the atom-wall distance appear. These logarithms are accompanied with logarithmic sums over virtual excitations of the atom interacting with the surface in analogy to Bethe logarithms in quantum electrodynamics. We verify the presence of the logarithmic terms in the short-range expansion using a model problem …

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Galaxy Clustering In The Mira-Titan Universe. I. Emulators For The Redshift Space Galaxy Correlation Function And Galaxy-Galaxy Lensing, Juliana Kwan, Shun Saito, Alexie Leauthaud, Katrin Heitmann, Salman Habib, Nicholas Frontiere, Hong Guo, Song Huang, Adrian Pope, Sergio Rodriguéz-Torres Jul 2023

Galaxy Clustering In The Mira-Titan Universe. I. Emulators For The Redshift Space Galaxy Correlation Function And Galaxy-Galaxy Lensing, Juliana Kwan, Shun Saito, Alexie Leauthaud, Katrin Heitmann, Salman Habib, Nicholas Frontiere, Hong Guo, Song Huang, Adrian Pope, Sergio Rodriguéz-Torres

Physics Faculty Research & Creative Works

We construct accurate emulators for the projected and redshift space galaxy correlation functions and excess surface density as measured by galaxy-galaxy lensing, based on halo occupation distribution modeling. Using the complete Mira-Titan suite of 111 N-body simulations, our emulators vary over eight cosmological parameters and include the effects of neutrino mass and dynamical dark energy. We demonstrate that our emulators are sufficiently accurate for the analysis of the Baryon Oscillation Spectroscopic Survey DR12 CMASS galaxy sample over the range 0.5 ≤ r ≤ 50 h −1 Mpc. Furthermore, we show that our emulators are capable of recovering unbiased cosmological constraints …

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Algebraic Approach To Relativistic Landau Levels In The Symmetric Gauge, Ulrich D. Jentschura Jul 2023

Algebraic Approach To Relativistic Landau Levels In The Symmetric Gauge, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We use an algebraic approach to the calculation of Landau levels for a uniform magnetic field in the symmetric gauge with a vector potential A→=12(B→xr→), where B→ is assumed to be constant. The magnetron quantum number constitutes the degeneracy index. An overall complex phase of the wave function, given in terms of Laguerre polynomials, is a consequence of the algebraic structure. The relativistic generalization of the treatment leads to fully relativistic bispinor Landau levels in the symmetric gauge, in a representation which writes the relativistic states in terms of their nonrelativistic limit, and an algebraically accessible lower bispinor component. Negative-energy …

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Memory-Multi-Fractional Brownian Motion With Continuous Correlations, Wei Wang, Michał Balcerek, Krzysztof Burnecki, Aleksei V. Chechkin, Skirmantas Janušonis, Jakub Ślȩzak, Thomas Vojta, Agnieszka Wyłomańska, Ralf Metzler Jul 2023

Memory-Multi-Fractional Brownian Motion With Continuous Correlations, Wei Wang, Michał Balcerek, Krzysztof Burnecki, Aleksei V. Chechkin, Skirmantas Janušonis, Jakub Ślȩzak, Thomas Vojta, Agnieszka Wyłomańska, Ralf Metzler

Physics Faculty Research & Creative Works

We propose a generalization of the widely used fractional Brownian motion (FBM), memory-multi-FBM (MMFBM), to describe viscoelastic or persistent anomalous diffusion with time-dependent memory exponent α(t) in a changing environment. In MMFBM the built-in, long-range memory is continuously modulated by α(t). We derive the essential statistical properties of MMFBM such as its response function, mean-squared displacement (MSD), autocovariance function, and Gaussian distribution. In contrast to existing forms of FBM with time-varying memory exponents but a reset memory structure, the instantaneous dynamic of MMFBM is influenced by the process history, e.g., we show that after a steplike change of α(t) the …

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On The Development Of Part-Scale Fem Modeling For Laser Powder Bed Fusion Of Aisi 316l Stainless Steel With Experimental Verification, Muhammad Arif Mahmood, Asif Ur Rehman, M. Mustafa Azeem, Abedalkader Alkhouzaam, Marwan Khraisheh Jul 2023

On The Development Of Part-Scale Fem Modeling For Laser Powder Bed Fusion Of Aisi 316l Stainless Steel With Experimental Verification, Muhammad Arif Mahmood, Asif Ur Rehman, M. Mustafa Azeem, Abedalkader Alkhouzaam, Marwan Khraisheh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In laser powder bed fusion (LPBF), the effects of operating conditions on thermal gradients and residual stresses are the utmost challenges that require significant attention. The magnitudes of residual stress in the printed layers, as well as the distribution along the printed components, have not been well explained for LPBF parts. In this study, a 3D finite element thermo-mechanical model has been established to investigate the effect of operating conditions on thermal distribution, melt pool evolution, residual stress distribution, and part distortion. The printed AISI 316L stainless steel cubes have been characterized experimentally. The results showed a proportional correlation among …

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Nonmonotonic Effect Of Chemical Heterogeneity On Interfacial Crack Growth At High-Angle Grain Boundaries In Fe-Ni-Cr Alloys, Yuchu Wang, Bita Ghaffari, Christopher Taylor, Simon Lekakh, Carlos Engler-Pinto, Larry Godlewski, Yang Huo, Mei Li, Yue Fan Jul 2023

Nonmonotonic Effect Of Chemical Heterogeneity On Interfacial Crack Growth At High-Angle Grain Boundaries In Fe-Ni-Cr Alloys, Yuchu Wang, Bita Ghaffari, Christopher Taylor, Simon Lekakh, Carlos Engler-Pinto, Larry Godlewski, Yang Huo, Mei Li, Yue Fan

Electrical and Computer Engineering Faculty Research & Creative Works

An intermittent pattern is observed in the modeling of interfacial cyclic-loading crack growth at high-angle grain boundaries in ternary Fe-Ni-Cr alloys. Different from conventional wisdom of stress-intensity factor, the abrupt crack advances are found driven by extreme value statistics - namely, the aggregation of atoms with most compressive residual stresses. In addition, inherently non-affine atomic stress fluctuations are discovered, and the fluctuations peak at intermediate level of chemical heterogeneity, causing the fastest crack growth. Implications of such nonmonotonic mechanism in regard to the origin of intermediate-temperature embrittlement phenomena are also discussed.

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Prediction Of Compressive Strength And Evaluation Of Different Theoretical Standards And Proposed Models Of Brick Columns Confined With Frp, Frcm, Or Srg System, Zuhair Al-Jaberi, John J. Myers Jul 2023

Prediction Of Compressive Strength And Evaluation Of Different Theoretical Standards And Proposed Models Of Brick Columns Confined With Frp, Frcm, Or Srg System, Zuhair Al-Jaberi, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Strength Capacity of Confined Masonry Column is One of the Topics that Need to Be Studied. in This Study, the Efficiency of using Different Types of Advanced Composite (Non-Corrosive Materials) Such as Fiber Reinforced Polymer (FRP), Fiber Reinforced Cementitious Matrix (FRCM), or Steel Reinforced Grout (SRG) in Confining Masonry Columns is Investigated. a Wide Range of Experimental Database of Masonry Column Specimens Has Been Collected from the Results that Available in Scientific Literatures. Different Theoretical Standards and Proposed Models that Used to Predict the Capacity of Masonry Columns Confined with FRP and FRCM Are Evaluated based on Collected Experimental …

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