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Articles 181 - 210 of 6056

Full-Text Articles in Physical Sciences and Mathematics

Ontogenetically Driven Changes In The Endocranial Anatomy Of Maiasaura Peeblesorum And Its Implications For Sensory Functions, Emma Puetz Jan 2024

Ontogenetically Driven Changes In The Endocranial Anatomy Of Maiasaura Peeblesorum And Its Implications For Sensory Functions, Emma Puetz

Masters Theses

"Hadrosaurids exhibited extreme morphological diversity and behavioral characteristics that can be compared with other, closely related members of Dinosauria – particularly through the study of neuroanatomy. X-ray CT generated endocrania of the Late Cretaceous saurolophine hadrosaur Maiasaura peeblesorum, known as the “good mother” dinosaur, offers a unique opportunity to compare complex ecological behaviors between non-avian dinosaurs and their modern archosaur relatives. The 3D reconstruction software ORS Dragonfly provided linear and volumetric measurements taken from the digital cranial endocast and endosseous labyrinths of three ontogenetically varied M. peeblesorum specimens from the Two Medicine Formation in Montana that were used to …

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Many-Body Quantum Chaos In Stroboscopically-Driven Cold Atoms, Ceren B. Dağ, Simeon I. Mistakidis, Amos Chan, H. R. Sadeghpour Dec 2023

Many-Body Quantum Chaos In Stroboscopically-Driven Cold Atoms, Ceren B. Dağ, Simeon I. Mistakidis, Amos Chan, H. R. Sadeghpour

Physics Faculty Research & Creative Works

In Quantum Chaotic Systems, The Spectral Form Factor (SFF), Defined As The Fourier Transform Of Two-Level Spectral Correlation Function, Is Known To Follow Random Matrix Theory (RMT), Namely A 'ramp' Followed By A 'plateau' In Late Times. Recently, A Generic Early-Time Deviation From RMT, So-Called The 'bump', Was Shown To Exist In Random Quantum Circuits As Toy Models For Many-Body Quantum Systems. We Demonstrate The Existence Of 'bump-Ramp-Plateau' Behavior In The SFF For A Number Of Paradigmatic And Stroboscopically-Driven 1D Cold-Atom Models: Spinless And Spin-1/2 Bose-Hubbard Models, And Nonintegrable Spin-1 Condensate With Contact Or Dipolar Interactions. We Find That The …

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Insight Into The Binding Of Argon To Cyclic Water Clusters From Symmetry-Adapted Perturbation Theory, Carly A. Rock, Gregory S. Tschumper Dec 2023

Insight Into The Binding Of Argon To Cyclic Water Clusters From Symmetry-Adapted Perturbation Theory, Carly A. Rock, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work systematically examines the interactions between a single argon atom and the edges and faces of cyclic H (Formula presented.) O clusters containing three–five water molecules (Ar(H (Formula presented.) O) (Formula presented.)). Full geometry optimizations and subsequent harmonic vibrational frequency computations were performed using MP2 with a triple- (Formula presented.) correlation consistent basis set augmented with diffuse functions on the heavy atoms (cc-pVTZ for H and aug-cc-pVTZ for O and Ar; denoted as haTZ). Optimized structures and harmonic vibrational frequencies were also obtained with the two-body–many-body (2b:Mb) and three-body–many-body (3b:Mb) techniques; here, high-level CCSD(T) computations capture up through the …

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A Parallel Algorithm For Updating A Multi-Objective Shortest Path In Large Dynamic Networks, Arindam Khanda, S. M. Shovan, Sajal K. Das Nov 2023

A Parallel Algorithm For Updating A Multi-Objective Shortest Path In Large Dynamic Networks, Arindam Khanda, S. M. Shovan, Sajal K. Das

Computer Science Faculty Research & Creative Works

In dynamic networks, where continuous topological changes are prevalent, it becomes paramount to find and update different graph properties without the computational burden of recalculating from the ground up. However finding or updating a multi-objective shortest path (MOSP) in such a network is challenging, as it involves simultaneously optimizing multiple (conflicting) objectives. In light of this, our paper focuses on shortest path search and proposes parallel algorithms tailored specifically for large incremental graphs. We first present an efficient algorithm that updates the single-objective shortest path (SOSP) whenever a new set of edges are introduced. Leveraging this SOSP update algorithm, we …

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Fabrication Process Independent And Robust Aggregation Of Detonation Nanodiamonds In Aqueous Media, Inga C. Kuschnerus, Haotian Wen, Xinrui Zeng, Yee Yee Khine, Juanfang Ruan, Chun Jen Su, U. Ser Jeng, Hugues A. Girard, Jean Charles Arnault, Eiji Ōsawa, Olga Shenderova, Vadym Mochalin, Ming Liu, Masahiro Nishikawa Nov 2023

Fabrication Process Independent And Robust Aggregation Of Detonation Nanodiamonds In Aqueous Media, Inga C. Kuschnerus, Haotian Wen, Xinrui Zeng, Yee Yee Khine, Juanfang Ruan, Chun Jen Su, U. Ser Jeng, Hugues A. Girard, Jean Charles Arnault, Eiji Ōsawa, Olga Shenderova, Vadym Mochalin, Ming Liu, Masahiro Nishikawa

Chemistry Faculty Research & Creative Works

In the past detonation nanodiamonds (DNDs), sized 3–5 nm, have been praised for their colloidal stability in aqueous media, thereby attracting vast interest in a wide range of applications including nanomedicine. More recent studies have challenged the consensus that DNDs are monodispersed after their fabrication process, with their aggregate formation dynamics poorly understood. Here we reveal that DNDs in aqueous solution, regardless of their post-synthesis de-agglomeration and purification methods, exhibit hierarchical aggregation structures consisting of chain-like and cluster aggregate morphologies. With a novel characterization approach combining machine learning with direct cryo-transmission electron microscopy and with X-ray scattering and vibrational spectroscopy, …

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Oxidative Stress In Health And Disease, V. Prakash Reddy Nov 2023

Oxidative Stress In Health And Disease, V. Prakash Reddy

Chemistry Faculty Research & Creative Works

Oxidative stress, resulting from the excessive intracellular accumulation of reactive oxygen species (ROS), reactive nitrogen species (RNS), and other free radical species, contributes to the onset and progression of various diseases, including diabetes, obesity, diabetic nephropathy, diabetic neuropathy, and neurological diseases, such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). Oxidative stress is also implicated in cardiovascular disease and cancer. Exacerbated oxidative stress leads to the accelerated formation of advanced glycation end products (AGEs), a complex mixture of crosslinked proteins and protein modifications. Relatively high levels of AGEs are generated in diabetes, obesity, AD, and other …

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Demo-Abstract: A Dtn System For Tracking Miners Using Gae-Lstm And Contact Graph Routing In An Underground Mine, Abhay Goyal, Sanjay Kumar Madria, Samuel Frimpong Oct 2023

Demo-Abstract: A Dtn System For Tracking Miners Using Gae-Lstm And Contact Graph Routing In An Underground Mine, Abhay Goyal, Sanjay Kumar Madria, Samuel Frimpong

Computer Science Faculty Research & Creative Works

Localization and prediction of movement of miners in underground mines have been a constant problem more so during a mine disaster. Due to the unavailability of GPS signals, the pillars are used as a method to locate these miners, and thus, location prediction is also carried out with reference to these pillars. In this work, we demon- strate a Delay-tolerant Network (DTN) system called Miner-Finder that leverages Machine Learning (ML) framework (GAE-LSTM) that works on edge devices (e.g., mobile phones, tablets) to predict the location of miners in an underground mine. The information such as speed, angle, time, nearest pillar …

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Hprop: Hierarchical Privacy-Preserving Route Planning For Smart Cities, Francis Tiausas, Keiichi Yasumoto, Jose Paolo Talusan, Hayato Yamana, Hirozumi Yamaguchi, Shameek Bhattacharjee, Abhishek Dubey, Sajal K. Das Oct 2023

Hprop: Hierarchical Privacy-Preserving Route Planning For Smart Cities, Francis Tiausas, Keiichi Yasumoto, Jose Paolo Talusan, Hayato Yamana, Hirozumi Yamaguchi, Shameek Bhattacharjee, Abhishek Dubey, Sajal K. Das

Computer Science Faculty Research & Creative Works

Route Planning Systems (RPS) are a core component of autonomous personal transport systems essential for safe and efficient navigation of dynamic urban environments with the support of edge-based smart city infrastructure, but they also raise concerns about user route privacy in the context of both privately owned and commercial vehicles. Numerous high-profile data breaches in recent years have fortunately motivated research on privacy preserving RPS, but most of them are rendered impractical by greatly increased communication and processing overhead. We address this by proposing an approach called Hierarchical Privacy-Preserving Route Planning (HPRoP), which divides and distributes the route-planning task across …

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Ab Initio Quantum Scattering Calculations And A New Potential Energy Surface For The Hcl(X¹Σ+)-O2( X 3 Σ G − ) System: Collision-Induced Line Shape Parameters For O2-Perturbed R(0) 0-0 Line In H35cl, Artur Olejnik, Hubert Jóźwiak, Maciej Gancewski, Ernesto Quintas-Sánchez, Richard Dawes, Piotr Wcisło Oct 2023

Ab Initio Quantum Scattering Calculations And A New Potential Energy Surface For The Hcl(X¹Σ+)-O2( X 3 Σ G − ) System: Collision-Induced Line Shape Parameters For O2-Perturbed R(0) 0-0 Line In H35cl, Artur Olejnik, Hubert Jóźwiak, Maciej Gancewski, Ernesto Quintas-Sánchez, Richard Dawes, Piotr Wcisło

Chemistry Faculty Research & Creative Works

The Remote Sensing of Abundance and Properties of HCl—the Main Atmospheric Reservoir of Cl Atoms that Directly Participate in Ozone Depletion—is Important for Monitoring the Partitioning of Chlorine between "Ozone-Depleting" and "Reservoir" Species. Such Remote Studies Require Knowledge of the Shapes of Molecular Resonances of HCl, Which Are Perturbed by Collisions with the Molecules of the Surrounding Air. in This Work, We Report the First Fully Quantum Calculations of Collisional Perturbations of the Shape of a Pure Rotational Line in H35Cl Perturbed by an Air-Relevant Molecule [As the First Model System We Choose the R(0) Line in HCl Perturbed by …

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Catching Elusive Depression Via Facial Micro-Expression Recognition, Xiaohui Chen, Tony Tie (T.) Luo Oct 2023

Catching Elusive Depression Via Facial Micro-Expression Recognition, Xiaohui Chen, Tony Tie (T.) Luo

Computer Science Faculty Research & Creative Works

Depression is a common mental health disorder that can cause consequential symptoms with continuously depressed mood that leads to emotional distress. One category of depression is Concealed Depression, where patients intentionally or unintentionally hide their genuine emotions through exterior optimism, thereby complicating and delaying diagnosis and treatment and leading to unexpected suicides. In this article, we propose to diagnose concealed depression by using facial micro-expressions (FMEs) to detect and recognize underlying true emotions. However, the extremely low intensity and subtle nature of FMEs make their recognition a tough task. We propose a facial landmark-based Region-of-Interest (ROI) approach to address the …

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Modulation Of Electrocatalytic Activity By Tuning Anion Electronegativity: Case Study With Copper Chalcogenides, Harish Singh, David Prendergast, Manashi Nath Oct 2023

Modulation Of Electrocatalytic Activity By Tuning Anion Electronegativity: Case Study With Copper Chalcogenides, Harish Singh, David Prendergast, Manashi Nath

Chemistry Faculty Research & Creative Works

Anion-tuning in metallic chalcogenides has been shown to have a significant impact on their electrocatalytic ability for overall water splitting. In this article, copper-based chalcogenides (Cu2 X, X= O, S, Se, and Te) have been systematically studied to examine the effect of decreasing anion electronegativity and increasing covalency on the electrocatalytic performance. Among the copper chalcogenides, Cu2Te has the highest oxygen evolution reaction (OER) activity and can sustain high current density of 10 and 50 mA cm−2 for 12 h. The difference in intrinsic catalytic activity of these chalcogenide surfaces have been also probed through density functional theory calculations, which …

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Affine Image Registration Of Arterial Spin Labeling Mri Using Deep Learning Networks, Zongpai Zhang, Huiyuan Yang, Yanchen Guo, Nicolas R. Bolo, Matcheri Keshavan, Eve Derosa, Adam K. Anderson, David C. Alsop, Lijun Yin, Weiying Dai Oct 2023

Affine Image Registration Of Arterial Spin Labeling Mri Using Deep Learning Networks, Zongpai Zhang, Huiyuan Yang, Yanchen Guo, Nicolas R. Bolo, Matcheri Keshavan, Eve Derosa, Adam K. Anderson, David C. Alsop, Lijun Yin, Weiying Dai

Computer Science Faculty Research & Creative Works

Convolutional neural networks (CNN) have demonstrated good accuracy and speed in spatially registering high signal-to-noise ratio (SNR) structural magnetic resonance imaging (sMRI) images. However, some functional magnetic resonance imaging (fMRI) images, e.g., those acquired from arterial spin labeling (ASL) perfusion fMRI, are of intrinsically low SNR and therefore the quality of registering ASL images using CNN is not clear. In this work, we aimed to explore the feasibility of a CNN-based affine registration network (ARN) for registration of low-SNR three-dimensional ASL perfusion image time series and compare its performance with that from the state-of-the-art statistical parametric mapping (SPM) algorithm. The …

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Interferometry Of Efimov States In Thermal Gases By Modulated Magnetic Fields, G. Bougas, Simeon I. Mistakidis, P. Schmelcher, C. H. Greene, P. Giannakeas Oct 2023

Interferometry Of Efimov States In Thermal Gases By Modulated Magnetic Fields, G. Bougas, Simeon I. Mistakidis, P. Schmelcher, C. H. Greene, P. Giannakeas

Physics Faculty Research & Creative Works

We Demonstrate That An Interferometer Based On Modulated Magnetic Field Pulses Enables Precise Characterization Of The Energies And Lifetimes Of Efimov Trimers Irrespective Of The Magnitude And Sign Of The Interactions In Rb85 Thermal Gases. Despite Thermal Effects, Interference Fringes Develop When The Dark Time Between The Pulses Is Varied. This Enables The Selective Excitation Of Coherent Superpositions Of Trimer, Dimer, And Free-Atom States. The Interference Patterns Possess Two Distinct Damping Timescales At Short And Long Dark Times That Are Either Equal To Or Twice As Long As The Lifetime Of Efimov Trimers, Respectively. Specifically, This Behavior At Long Dark …

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Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das Sep 2023

Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das

Computer Science Faculty Research & Creative Works

In the last few years, Federated Learning (FL) has received extensive attention from the research community because of its capability for privacy-preserving, collaborative learning from heterogeneous data sources. Most FL studies focus on either average performance improvement or the robustness to attacks, while some attempt to solve both jointly. However, the performance disparities across clients in the presence of attackers have largely been unexplored. In this work, we propose a novel Fair Federated Learning scheme with Attacker Detection capability (abbreviated as FFL+AD) to minimize performance discrepancies across benign participants. FFL+AD enables the server to identify attackers and learn their malign …

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Ambient Processed Rgo/Ti3cntx Mxene Thin Film With High Oxidation Stability, Photosensitivity, And Self-Cleaning Potential, Muhammad Abiyyu Kenichi Purbayanto, Dominika Bury, Madhurya Chandel, Zhila Dehghan Shahrak, Vadym Mochalin, Anna Wójcik, Dorota Moszczyńska, Anita Wojciechowska, Anika Tabassum, Michael Naguib, Agnieszka Maria Jastrzębska Sep 2023

Ambient Processed Rgo/Ti3cntx Mxene Thin Film With High Oxidation Stability, Photosensitivity, And Self-Cleaning Potential, Muhammad Abiyyu Kenichi Purbayanto, Dominika Bury, Madhurya Chandel, Zhila Dehghan Shahrak, Vadym Mochalin, Anna Wójcik, Dorota Moszczyńska, Anita Wojciechowska, Anika Tabassum, Michael Naguib, Agnieszka Maria Jastrzębska

Chemistry Faculty Research & Creative Works

Solution-Based Processing Offers Advantages for Producing Thin Films Due to Scalability, Low Cost, Simplicity, and Benignity to the Environment. Here, We Develop Conductive and Photoactivated Self-Cleaning Reduced Graphene Oxide (RGO)/Ti3CNTx MXene Thin Films Via Spin Coating under Ambient Conditions. the Addition of a Thin RGO Layer on Top of Ti3CNTx Resulted in Up to 45-Fold Improvement in the Environmental Stability of the Film Compared to the Bare Ti3CNTx Film. the Optimized RGO/Ti3CNTx Thin Film Exhibits an Optical Transmittance of 74% in the Visible Region of the Spectrum and …

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Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan Sep 2023

Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Recently Introduced Deep Reinforcement Learning (DRL) Techniques in Discrete-Time Have Resulted in Significant Advances in Online Games, Robotics, and So On. Inspired from Recent Developments, We Have Proposed an Approach Referred to as Quantile Critic with Spiking Actor and Normalized Ensemble (QC-SANE) for Continuous Control Problems, Which Uses Quantile Loss to Train Critic and a Spiking Neural Network (NN) to Train an Ensemble of Actors. the NN Does an Internal Normalization using a Scaled Exponential Linear Unit (SELU) Activation Function and Ensures Robustness. the Empirical Study on Multijoint Dynamics with Contact (MuJoCo)-Based Environments Shows Improved Training and Test Results Than …

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Interactions And Dynamics Of One-Dimensional Droplets, Bubbles And Kinks, Garyfallia Katsimiga, Simeon I. Mistakidis, Boris A. Malomed, Dimitris J. Frantzeskakis, Ricardo Carretero-Gonzalez, Panayotis G. Kevrekidis Sep 2023

Interactions And Dynamics Of One-Dimensional Droplets, Bubbles And Kinks, Garyfallia Katsimiga, Simeon I. Mistakidis, Boris A. Malomed, Dimitris J. Frantzeskakis, Ricardo Carretero-Gonzalez, Panayotis G. Kevrekidis

Physics Faculty Research & Creative Works

We Explore The Dynamics And Interactions Of Multiple Bright Droplets And Bubbles, As Well As The Interactions Of Kinks With Droplets And With Antikinks, In The Extended One-Dimensional Gross–Pitaevskii Model Including The Lee–Huang–Yang Correction. Existence Regions Are Identified For The One-Dimensional Droplets And Bubbles In Terms Of Their Chemical Potential, Verifying The Stability Of The Droplets And Exposing The Instability Of The Bubbles. The Limiting Case Of The Droplet Family Is A Stable Kink. The Interactions Between Droplets Demonstrate In-Phase (Out-Of-Phase) Attraction (Repulsion), With The So-Called Manton's Method Explicating The Observed Dynamical Response, And Mixed Behavior For Intermediate Values Of …

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Crystal Environment Induced Symmetry Reduction (Ceisr): Deep Analysis Of Para-Chloroacetophenone Azine And Generalization, Harmeet Bhoday, Kaidi Yang, Steven P. Kelley, Rainer Glaser Aug 2023

Crystal Environment Induced Symmetry Reduction (Ceisr): Deep Analysis Of Para-Chloroacetophenone Azine And Generalization, Harmeet Bhoday, Kaidi Yang, Steven P. Kelley, Rainer Glaser

Chemistry Faculty Research & Creative Works

The morphologies of sixteen crystal structures of ten symmetrical Xpara-Ph-(Me)C 00000000 00000000 00000000 00000000 11111111 = N-N = C (Me)-Ph-Xpara azines: 1 (Cl), 2 (Br), 3 (I), 4 (OH), 5 (PhO), 6 (CF3), 7 (F), 8 (Me), 9 (NO2), and 10 (PrO) are described. All the azines crystallize forming idioteloamphiphile monolayers (IAMs) and their morphologies fall into the two main classes of "flat" and "shiplap" depending on the lateral offsets between next neighbors in the monolayer. Ab initio studies show that the (E,E)-configured p-disubstituted acetophenone azines are C2-symmetric in the gas phase and that the azine and phenyl twists are …

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Libra: Harvesting Idle Resources Safely And Timely In Serverless Clusters, Hanfei Yu, Christian Fontenot, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park Aug 2023

Libra: Harvesting Idle Resources Safely And Timely In Serverless Clusters, Hanfei Yu, Christian Fontenot, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park

Computer Science Faculty Research & Creative Works

Serverless computing has been favored by users and infrastructure providers from various industries, including online services and scientific computing. Users enjoy its auto-scaling and ease-of-management, and providers own more control to optimize their service. However, existing serverless platforms still require users to pre-define resource allocations for their functions, leading to frequent misconfiguration by inexperienced users in practice. Besides, functions' varying input data further escalate the gap between their dynamic resource demands and static allocations, leaving functions either over-provisioned or under-provisioned. This paper presents Libra, a safe and timely resource harvesting framework for multi-node serverless clusters. Libra makes precise harvesting decisions …

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Outgassing Behavior And Heat Treatment Optimization Of Jsc-1a Lunar Regolith Simulant, Ryan P. Wilkerson, Mihail P. Petkov, Gerald E. Voecks, Catherine S. Lynch, Holly S. Shulman, Santhoshkumar Sundaramoorthy, Amitava Choudhury, Douglas L. Rickman, Michael R. Effinger Aug 2023

Outgassing Behavior And Heat Treatment Optimization Of Jsc-1a Lunar Regolith Simulant, Ryan P. Wilkerson, Mihail P. Petkov, Gerald E. Voecks, Catherine S. Lynch, Holly S. Shulman, Santhoshkumar Sundaramoorthy, Amitava Choudhury, Douglas L. Rickman, Michael R. Effinger

Chemistry Faculty Research & Creative Works

As NASA Strives towards a Long Duration Presence on the Moon, It Has Become Increasingly Important to Learn How to Better Utilize Resources from the Lunar Surface for Everything from Habitats, Vehicle Infrastructure, and Chemical Extraction. to that End, a Variety of Lunar Simulants Have Been Sourced from Terrestrially Available Volcanic Minerals and Glass as Apollo Regolith is Unavailable for Experimentation Needing Large Masses. However, While Mineralogy and Chemical Composition Can Approach that of Lunar Material in These Simulants, There Are Still Distinct Non-Lunar Phases Such as Hydrates, Carbonates, Sulfates, and Clays that Can Cause Simulants to Behave Distinctly Non-Lunar …

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Quantum Electrodynamic Corrections To Cyclotron States In A Penning Trap, Ulrich D. Jentschura, Christopher Moore Aug 2023

Quantum Electrodynamic Corrections To Cyclotron States In A Penning Trap, Ulrich D. Jentschura, Christopher Moore

Physics Faculty Research & Creative Works

We analyze the leading and higher-order quantum electrodynamic corrections to the energy levels for a single electron bound in a Penning trap, including the Bethe logarithm correction due to virtual excitations of the reference quantum cyclotron state. The effective coupling parameter αc in the Penning trap is identified as the square root of the ratio of the cyclotron frequency, converted to an energy via multiplication by the Planck constant, to the electron rest mass energy. We find a large, state-independent, logarithmic one-loop self-energy correction of order α αc4mc2ln(αc-2), where m is the …

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Doubly Differential Ionization In Proton-Helium Collisions At Intermediate Energies: Energy Distribution Of Emitted Electrons As A Function Of Scattered-Projectile Angle, K. H. Spicer, C. T. Plowman, Michael Schulz, A. S. Kadyrov Aug 2023

Doubly Differential Ionization In Proton-Helium Collisions At Intermediate Energies: Energy Distribution Of Emitted Electrons As A Function Of Scattered-Projectile Angle, K. H. Spicer, C. T. Plowman, Michael Schulz, A. S. Kadyrov

Physics Faculty Research & Creative Works

Differential studies of the proton-helium scattering problem using the two-center wave-packet convergent close-coupling approach is extended to the calculation of the ionization cross section differential in the electron emission energy and the projectile scattering angle. The results obtained using the correlated two-electron and effective one-electron methods are in reasonably good agreement with experiment. While the shape of the doubly differential cross section generally agrees with the results of the experiment, at some emission energies its magnitude does not. This appears consistent with similar disagreement seen in the singly differential cross section at the same emission energies.

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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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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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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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