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Articles 61 - 90 of 13204
Full-Text Articles in Entire DC Network
Exploiting Underground Mine Topology For Resilient Concurrent Lora Mesh Emergency Communications: Architecture, Protocol Design, And Performance Analysis, Hilary Kelechi Anabi, Samuel Frimpong, Muhammad Azeem Raza
Exploiting Underground Mine Topology For Resilient Concurrent Lora Mesh Emergency Communications: Architecture, Protocol Design, And Performance Analysis, Hilary Kelechi Anabi, Samuel Frimpong, Muhammad Azeem Raza
Mining Engineering Faculty Research & Creative Works
Underground mine emergencies compromise fixed communication infrastructure exactly when situational awareness is most critical for effective rescue operations. Existing LoRa mesh protocols fail in underground mines because they ignore the structured topology of tunnel networks, specifically the waveguide effect along straight galleries, severe signal discontinuity at junctions, and the dead-end geometry of working faces. This paper presents the Topology-Aware Concurrent LoRa (TACL) mesh protocol, in which each node autonomously infers its structural role from local RF observations and packet header information, without GPS, pre-loaded mine maps, or central coordination. Role classification resolves the contender estimation problem (Formula presented.) left open …
Golden And Silver Dark Sirens For Precise H0 Measurement With Hetdex, Yixuan Dang, Ish Gupta, Robin Ciardullo, Erin Mentuch Cooper, Shiksha Pandey, Dustin Davis, Surhud More, Rachel Gray, Hsin Yu Chen, Daniel J. Farrow, Caryl Gronwall, Donghui Jeong, Shun Saito, Donald P. Schneider
Golden And Silver Dark Sirens For Precise H0 Measurement With Hetdex, Yixuan Dang, Ish Gupta, Robin Ciardullo, Erin Mentuch Cooper, Shiksha Pandey, Dustin Davis, Surhud More, Rachel Gray, Hsin Yu Chen, Daniel J. Farrow, Caryl Gronwall, Donghui Jeong, Shun Saito, Donald P. Schneider
Physics Faculty Research & Creative Works
Gravitational waves (GWs) from compact binary coalescences are standard sirens that provide a direct measure of the source's luminosity distance, enabling an independent measurement of the Hubble constant (H0). While a bright siren—a GW event with an identified electromagnetic (EM) counterpart—provided the first such constraint, most detections, currently dominated by black hole mergers, lack EM signatures. A measurement of H0 is still possible with these dark sirens by statistically associating GW events with galaxies in existing catalogs based on the sky localization. In this work, we explore the potential of two subsets of dark sirens categorized by their localization precision: …
Pso-Style Social Influence In An Ant Colony Algorithm For Continuous-Domain Optimization, Ashraf M. Abdelbar, Donald C. Wunsch
Pso-Style Social Influence In An Ant Colony Algorithm For Continuous-Domain Optimization, Ashraf M. Abdelbar, Donald C. Wunsch
Electrical and Computer Engineering Faculty Research & Creative Works
ACOR is a well-established Ant Colony Optimization (ACO) algorithm for continuous-domain optimization. In this paper, we propose an extension (which we call ACOR∗) in which several fundamental modifications are made to ACOR's solution construction process, including the incorporation of a social influence mechanism borrowed from Particle Swarm Optimization (PSO). Our modifications to the ACOR algorithm are intended to promote search diversity and combat premature convergence. We experimentally evaluate our proposal in the context of training feedforward neural networks for classification using 65 widely used datasets from the University of California Irvine (UCI) repository, as well as the optimization of several …
Multiplexed Fabry-Pérot High-Temperature Sensing Based On Dispersive Microwave-Photonic Frequency-Time Domain Analysis, Ruimin Jie, Chen Zhu, Bohong Zhang, Koustav Dey, Jie Huang
Multiplexed Fabry-Pérot High-Temperature Sensing Based On Dispersive Microwave-Photonic Frequency-Time Domain Analysis, Ruimin Jie, Chen Zhu, Bohong Zhang, Koustav Dey, Jie Huang
Electrical and Computer Engineering Faculty Research & Creative Works
We propose and experimentally demonstrate a multiplexed high-temperature Fabry-Pérot (FP) fiber sensing system interrogated by dispersive microwave-photonic frequency-time domain analysis (DM-FTDA). In the proposed architecture, incoherent broadband probing light is modulated by radio-frequency (RF) signals and then reflected by a parallel network of hollow-core photonic crystal fiber FP (HCPCF-FP) sensors. A chirped fiber Bragg grating provides strong dispersion to map the composite FP spectral response into a well-defined microwave transfer function. Unlike conventional optical Fourier-domain multiplexing that requires deliberate cavity-length allocation, the proposed approach achieves multiplexing via delay-dominated discrimination. Distinct delay fibers are assigned to each sensor branch, and an …
A Fiftieth Year Retrospective On The 1976 Mw 7.5 Motagua Earthquake In Guatemala, Grant Clark, Trenton Mcenaney, Jeremy Maurer, Andreas Eckert, Stephen S. Gao, Omar G. Flores, Robin Yani, Tina Niemi, Christoph Grützner, Francisco Gomez, Jonathan Obrist-Farner
A Fiftieth Year Retrospective On The 1976 Mw 7.5 Motagua Earthquake In Guatemala, Grant Clark, Trenton Mcenaney, Jeremy Maurer, Andreas Eckert, Stephen S. Gao, Omar G. Flores, Robin Yani, Tina Niemi, Christoph Grützner, Francisco Gomez, Jonathan Obrist-Farner
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
On 4 February 1976, an Mw > 7:5 earthquake ruptured ∼240 km of the Motagua fault in Guatemala, causing ∼23,000 fatalities. This event provided evidence for the fault's role as a major transform boundary between the North American and Caribbean plates. Field observations, seismological analyses, and postseismic studies helped constrain fundamental aspects of the 1976 earthquake mechanics and the spatial complexity of the rupture. This event opened a window for studies documenting past deformation along this plate boundary across multiple spatial and temporal scales. Five decades of research have established this earthquake as an important event for understanding strike-slip ruptures along …
Phase Field Modeling And A Fully Discrete Numerical Scheme For Two-Phase Incompressible Mhd Flows With Different Densities, Electric Conductivities And Viscosities, Xiaoyong Chen, Rui Li, Jian Li, Xiaoming He, Yanping Lin
Phase Field Modeling And A Fully Discrete Numerical Scheme For Two-Phase Incompressible Mhd Flows With Different Densities, Electric Conductivities And Viscosities, Xiaoyong Chen, Rui Li, Jian Li, Xiaoming He, Yanping Lin
Mathematics and Statistics Faculty Research & Creative Works
This article establishes a phase field model for governing the two-phase incompressible MHD flows with different densities, electric conductivities, and viscosities. In addition to the coupling between the Cahn–Hilliard phase field equations and the single-phase MHD equations together with the varying parameters, it is physically faithful and mathematically rigorous for the modeling to incorporate a relative flux term, which is related to the diffusion of the components, into the coupled system, inspired by Abels et al. and Shen and Yang. We present a linear fully discrete numerical scheme for this complex multi-physics system, which leverages the artificial compressibility method, an …
Explicit Hydration Of The Beryllium Trifluoride Anion With One To Three Water Molecules: Bef3–(H2o)N=1–3, Kayleigh R. Autry, Gregory S. Tschumper
Explicit Hydration Of The Beryllium Trifluoride Anion With One To Three Water Molecules: Bef3–(H2o)N=1–3, Kayleigh R. Autry, Gregory S. Tschumper
Chemistry Faculty Research & Creative Works
This work investigates the micro hydration of the beryllium trifluoride anion (BeF3–) with up to three water molecules (BeF3–(H2O)n where n = 1–3). Full geometry optimizations and harmonic vibrational frequencies were computed on various BeF3–(H2O)n stationary points using density functional theory methods (B3LYP-D3BJ, B3LYP, ωB97XD, and M06-2X) as well as the CCSD(T) and MP2 ab initio methods with a triple-ζ correlation-consistent basis set augmented with diffuse functions on all non-hydrogen atoms (haTZ). One BeF3–(H2O)1, five BeF3– …
Genetic Analysis Of Triplicated Genes Affecting Sex-Specific Skeletal Deficits In Down Syndrome Model Mice, Kourtney Sloan, Kristina M. Piner, Pathum Randunu Nawarathna Kandedura Arachchige, Charles R. Goodlett, Yann Herault, Gayla R. Olbricht, Joseph M. Wallace, Randall J. Roper
Genetic Analysis Of Triplicated Genes Affecting Sex-Specific Skeletal Deficits In Down Syndrome Model Mice, Kourtney Sloan, Kristina M. Piner, Pathum Randunu Nawarathna Kandedura Arachchige, Charles R. Goodlett, Yann Herault, Gayla R. Olbricht, Joseph M. Wallace, Randall J. Roper
Mathematics and Statistics Faculty Research & Creative Works
Down syndrome (DS) is caused by the triplication of human chromosome 21 (Hsa21), resulting in skeletal insufficiency (low bone mineral density) and altered bone development. DS mouse models recapitulate these deficits, including sexual dimorphism in long bone alterations. Historically, Ts65Dn mice provided much of the insight behind DS-related skeletal deficits with ∼100 trisomic orthologous genes, but there are concerns about the genetic fidelity in this model due to the included triplication of genes not homologous to Hsa21. A new DS model, Ts66Yah, subtracted the non-Hsa21 homologous trisomic genes from Ts65Dn but has not been evaluated for long bone deficits. Comparing …
Multi-Population Sufficient Dimension Reduction, Xuerong Meggie Wen, Yuexiao Dong, Li Xing Zhu
Multi-Population Sufficient Dimension Reduction, Xuerong Meggie Wen, Yuexiao Dong, Li Xing Zhu
Mathematics and Statistics Faculty Research & Creative Works
A novel dimension-reduction method is introduced for multi-population data. The approach conducts a joint analysis that exploits information shared across populations while accommodating population-specific effects. Unlike partial dimension reduction methods, which identify related directions across all populations, or conditional analyses conducted independently within each population, the proposed two-step procedure leverages cross-population information to enhance estimation accuracy. The methodology is demonstrated through simulations and two real-data applications.
A Low-Rank Solver For The Stokes–Darcy Model With Random Hydraulic Conductivity And Beavers–Joseph Condition, Yujun Zhu, Yulan Ning, Zhipeng Yang, Xiaoming He, Ju Ming
A Low-Rank Solver For The Stokes–Darcy Model With Random Hydraulic Conductivity And Beavers–Joseph Condition, Yujun Zhu, Yulan Ning, Zhipeng Yang, Xiaoming He, Ju Ming
Mathematics and Statistics Faculty Research & Creative Works
This paper proposes, analyzes, and demonstrates an efficient low-rank solver for the stochastic Stokes-Darcy interface model with a random hydraulic conductivity both in the porous media domain and on the interface. We consider three interface conditions with randomness, including the Beavers–Joseph interface condition with the random hydraulic conductivity, on the interface between the free flow and the porous media flow. Our solver employs a novel generalized low-rank approximation of the large-scale stiffness matrices, which can significantly cut down the computational costs and memory requirements associated with matrix inversion without losing accuracy. Therefore, by adopting a suitable data compression ratio, the …
Effect Of Composition On Grain-Boundary Chemistry And Fracture Behavior In High-Entropy Carbides, Caleb Schenck, Marium Mostafiz Mou, Elizabeth Pritchett, Fu Yun Tsai, Josephine Hartmann, Michael Lastovich, Sam Daigle, Kayla Yano, Matthew J. Olszta, Sanjit Bhowick, Elizabeth Kautz, Gregory E. Hilmas, William G. Fahrenholtz, Donald W. Brenner
Effect Of Composition On Grain-Boundary Chemistry And Fracture Behavior In High-Entropy Carbides, Caleb Schenck, Marium Mostafiz Mou, Elizabeth Pritchett, Fu Yun Tsai, Josephine Hartmann, Michael Lastovich, Sam Daigle, Kayla Yano, Matthew J. Olszta, Sanjit Bhowick, Elizabeth Kautz, Gregory E. Hilmas, William G. Fahrenholtz, Donald W. Brenner
Materials Science and Engineering Faculty Research & Creative Works
High-entropy carbides (HECs) are often treated as a single material class defined by configurational entropy; however, their properties are governed by composition-specific defects and grain-boundary chemistry. This study demonstrates that substituting a single element can qualitatively change grain-boundary structure and fracture behavior in HEC ceramics. Two HECs, (Cr,Hf,Ta,Ti,Zr)C (HEC-Cr) and (Hf,Ta,Ti,W,Zr)C (HEC-W), were examined via electron microscopy, atom probe tomography, and molecular dynamics simulations. Simulations predict preferential segregation of Cr, W, and Zr to grain boundaries. Experiments confirmed Cr enrichment at grain boundaries and the formation of W-rich nanograins along boundary networks. Mechanical testing revealed that these compositional differences translated …
Evaluating The Integration Of Bio-Based Waste Into Cement Production: A Pathway To Sustainable Building, Anja Terzić, Suzana Filipović, Adriana Peleš Tadić, Jelena Živojinović, Ivana N. Jelić, Nina Obradović, William G. Fahrenholtz
Evaluating The Integration Of Bio-Based Waste Into Cement Production: A Pathway To Sustainable Building, Anja Terzić, Suzana Filipović, Adriana Peleš Tadić, Jelena Živojinović, Ivana N. Jelić, Nina Obradović, William G. Fahrenholtz
Materials Science and Engineering Faculty Research & Creative Works
Rapid urbanization has increased the demand for building materials, depleting natural resources used in cement production and prompting the use of alternative and waste materials. This research verifies that eggshell powder waste can fully replace limestone in clinker synthesis. Five clinkers were produced using eggshell powder, aluminum sources (bentonite, zeolite, fly ash, and kaolinitic–illitic clay), Fe-slag, and quartz sand, with mechanical preprocessing (10–30 min) before sintering at 1300 °C. Experimental tests assessed the effects of mix design and mechanical activation on clinkerization, phase formation, temperature, and mechanical properties. XRD, FTIR, and SEM/EDS confirmed consistent phase compositions and primary cement minerals. …
Machine Vision For In Situ Measurement And Control Of Wire Stickout In Lwded Process, Braden Mclain, Remy Mathenia, Todd Sparks, Frank Liou
Machine Vision For In Situ Measurement And Control Of Wire Stickout In Lwded Process, Braden Mclain, Remy Mathenia, Todd Sparks, Frank Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This work presents a machine-vision–based measurement and control framework for laser wire directed energy deposition (LWDED) processes. A visible-light camera system is used to capture meltpool images, from which a novel vision algorithm extracts the wire–meltpool interface location. By utilizing a camera that is rigidly mounted to the deposition head, the vision algorithm provides a relative measurement of the distance between the nozzle tip and the workpiece, also referred to as wire stickout. A proportional-derivative (PD) control strategy is implemented using the measured stickout as feedback to adjust deposition feedrate. Results show that the control system successfully compensates for improper …
Smart-Charge: Stable Matching Algorithm For Electric Vehicle Charging In Subscription-Based Models, Arindam Khanda, Anurag Satpathy, Sajal K. Das
Smart-Charge: Stable Matching Algorithm For Electric Vehicle Charging In Subscription-Based Models, Arindam Khanda, Anurag Satpathy, Sajal K. Das
Computer Science Faculty Research & Creative Works
The transition from internal combustion engine (ICE) to electric vehicles (EVs) introduces several challenges, including limited charging infrastructure, unpredictable charging wait times, and inefficient selection of charging points (CPs). To address these issues, we propose SMART-CHARGE, a framework that efficiently assigns EVs to CPs through an edge-level coordination mechanism within each service region, enforced by roadside units (RSUs). Operating under a novel subscription-based charging model, SMART-CHARGE enforces predefined charging time limits via service-level agreements (SLAs). The EV-CP assignment problem is formulated as a one-to-many matching game that captures EV user preferences. To construct bounded yet efficient EV coalitions at each …
Safepass: Efficient Emergency Vehicle Passage With Minimal Disruption To Traffic Flow, Osho Osho, Suchetana Chakraborty, Sajal K. Das
Safepass: Efficient Emergency Vehicle Passage With Minimal Disruption To Traffic Flow, Osho Osho, Suchetana Chakraborty, Sajal K. Das
Computer Science Faculty Research & Creative Works
Emergency vehicle passage in congested urban networks poses a dual challenge: ensuring rapid response while minimizing disruption to surrounding traffic. This study addresses this challenge in the context of Connected Autonomous Emergency Vehicles (CA-EVs), proposing SafePass , a lightweight distributed framework for seamless CA-EV passage through decentralized, cooperative maneuvering of surrounding Connected Autonomous Non-Emergency Vehicles (CA-NEVs). At its core, SafePass employs the Target Lane Potential (TLP), a novel utility-based metric combining lane-choice utility with probabilistic gap acceptance, augmented by a cascade-aware penalty that suppresses upstream shockwaves triggered by gap-creation maneuvers. Evaluated in Simulation of Urban Mobility (SUMO) using synthetic traffic …
Probing Composition Effects On The Intrinsic Energetics Of Proton Transfer In Binary (Hcl)M(H2o)N Clusters, Max R. Tucker, Sarah N. Arradondo, Olivia M. Longsworth, George C. Shields, Gregory S. Tschumper
Probing Composition Effects On The Intrinsic Energetics Of Proton Transfer In Binary (Hcl)M(H2o)N Clusters, Max R. Tucker, Sarah N. Arradondo, Olivia M. Longsworth, George C. Shields, Gregory S. Tschumper
Chemistry Faculty Research & Creative Works
This work examines the effects on intrinsic energetics as the composition of finite (HCl)m(H2O)n cluster families containing at least one water molecule is changed at the molecular level, where m ≥ 2 and m + n = 4 − 6, and the associated (Cl−)x(H3O+)x(HCl)m−x(H2O)n−x clusters resulting from the dissociation of x HCl fragments via proton transfer (PT). They are collectively labeled m:n, and xPT indicates the degree of dissociation, from 0PT (no dissociation) up to 3PT. More than 1000 unique minima …
Mechanism Of Improved Miscibility Of Co2–Oil Systems By Multiester-Headgroup Surfactants, Ning Xu, Yanling Wang, Baojun Bai, Yu Zhang, Wenjing Shi, Zhaonian Zhang, Wenhui Ding, Peixu Ma, Zan Gao
Mechanism Of Improved Miscibility Of Co2–Oil Systems By Multiester-Headgroup Surfactants, Ning Xu, Yanling Wang, Baojun Bai, Yu Zhang, Wenjing Shi, Zhaonian Zhang, Wenhui Ding, Peixu Ma, Zan Gao
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
In the pursuit of carbon neutrality, the CO2-enhanced oil recovery provides dual benefits by enabling both carbon sequestration and incremental oil production. However, its application is limited by high minimum miscibility pressure. CO2-philic and oil-affinitive surfactants have emerged as an effective, low-dosage, and cost-efficient strategy to reduce the minimum miscibility pressure. In this study, macroscopic phase behavior experiments combined with molecular dynamics simulations were employed to systematically elucidate the influence of multiester-head surfactants on CO2–oil miscibility. Using a modified pressure–volume–temperature apparatus equipped with optical power monitoring, we determined that multiester-head surfactants reduced the first-contact …
Uptake And Fate Of Silver And Zinc Engineered Nanoparticles In Maize Under Single And Binary Dosing Soil Ecosystems, Lei Xu, Qingbo Yang, Xingmao Ma, Honglan Shi, John Yang, Hu Yang, Samira Mahdi, Ying Wang, Young Shin Jun
Uptake And Fate Of Silver And Zinc Engineered Nanoparticles In Maize Under Single And Binary Dosing Soil Ecosystems, Lei Xu, Qingbo Yang, Xingmao Ma, Honglan Shi, John Yang, Hu Yang, Samira Mahdi, Ying Wang, Young Shin Jun
Chemistry Faculty Research & Creative Works
Recent agricultural applications of engineered metallic nanoparticles (ENPs) have raised concerns about their uptake and fate in plants. To understand this critical issue, this study investigated the fate and uptake of silver (Ag) and zinc oxide (ZnO) ENPs in maize (Zea mays L.) after single or binary ENP exposure in soil. Results indicated that both Zn and Ag elemental concentrations in roots increased with increasing ENP dosage. Ag NPs in the tissues were detected, but not Zn NPs. Ag NP concentration was 3 times higher in the roots than in the shoots at low Ag NP dosing, while Ag NP …
Electroenzymatic Cascades For Nitrogen Upgrading: Beyond Ammonia Towards Value-Added Nitrogen Chemicals, Rohit G. Jadhav, Vamshi Krishna Kamaja, Wassim El Housseini, Monica Brachi, Shelley D. Minteer
Electroenzymatic Cascades For Nitrogen Upgrading: Beyond Ammonia Towards Value-Added Nitrogen Chemicals, Rohit G. Jadhav, Vamshi Krishna Kamaja, Wassim El Housseini, Monica Brachi, Shelley D. Minteer
Chemistry Faculty Research & Creative Works
The global transition toward sustainable chemical manufacturing demands technologies that leverage natural carbon and nitrogen cycles while minimizing reliance on sacrificial reagents and fossil resources. These biogeochemical cycles are fundamental to life, and enzymes catalyze many of their key transformations. Bio electrochemical, specifically electroenzymatic, systems offer a promising route to sustainable synthesis by enabling selective redox transformations powered by electricity. However, whereas carbon-cycle enzymes are now well established in bio electrochemical synthesis, enzymes from the nitrogen cycle remain comparatively underexplored. Moreover, the nitrogen cycle alone does not access many value-added nitrogen-containing products, which require additional C-N bond formation and organic …
Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau
Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau
Chemistry Faculty Research & Creative Works
In the interstellar medium (ISM), non-local thermodynamic equilibrium situations are common due to low density, and one needs to consider the effect of molecular collisions in order to interpret the observations. Among the species detected in the ISM, cyanopolyynes, with the general molecular formula HC2n+1N (n = 1, 2, …), are characterized by large dipole moments and small rotational constants and constitute an indispensable class of candidates for the sensitive tracers of local density and temperature. We present a study of the collisional (de-) excitation of HC5N by para-H2 (p-H2) in its ground …
Characterizing User-Reported Risks Across Llm Chatbots, Lingyao Li, Renkai Ma, Zhaoqian Xue, Junjie Xiong
Characterizing User-Reported Risks Across Llm Chatbots, Lingyao Li, Renkai Ma, Zhaoqian Xue, Junjie Xiong
Computer Science Faculty Research & Creative Works
As Large Language Models (LLMs) become increasingly integral to daily life, users are engaging with multiple LLM chatbots for various needs; however, prior research on LLM risks often remains lab-based or focuses on single LLMs like ChatGPT or singular risks like privacy. To gain a multi-risk, cross-chatbot understanding of user experiences, we analyze Reddit discussions around seven major LLM chatbots using the NIST AI Risk Management Framework. We find that user-reported risks are unevenly distributed and chatbot-specific: ChatGPT is associated with safety and fairness concerns, Gemini with privacy, and Claude with security and resilience. Less frequent risks, such as explainability …
Evaluating Fine-Scale Air-Quality Heterogeneity Using A Low-Cost Multipollutant Sensor Network In Twin Cities, Minnesota, Varuni Abhayaratne, Weixing Hao, Chen Ye, Anjana Yatawara, Philip K. Hopke, Jiayu Li, Yang Wang
Evaluating Fine-Scale Air-Quality Heterogeneity Using A Low-Cost Multipollutant Sensor Network In Twin Cities, Minnesota, Varuni Abhayaratne, Weixing Hao, Chen Ye, Anjana Yatawara, Philip K. Hopke, Jiayu Li, Yang Wang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
There is growing interest and effort in deploying low-cost sensors (LCSs) to understand fine-scale spatiotemporal heterogeneity of ambient air pollutants in urban areas. The Assessing Urban Air Quality project conducted by the Minnesota Pollution Control Agency deployed 45 low-cost air-quality monitors (AQMesh, Environmental Instruments Ltd.) in the Minneapolis/St. Paul metropolitan area network. Hourly averaged pollutant concentrations or mixing ratios for carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), nitric oxide (NO), and sulfur dioxide (SO2), as well as particulate matter (PM), including PM1, PM2.5, and PM10, were obtained. The network data from June 2019 to June …
Synthesis And Hydrothermal Evaluation Of Poly(Styrene Phosphonate) For Conformance Control In Geothermal Reservoirs, Sara Mccauley
Synthesis And Hydrothermal Evaluation Of Poly(Styrene Phosphonate) For Conformance Control In Geothermal Reservoirs, Sara Mccauley
Miners Solving for Tomorrow Research Conference
As atmospheric carbon dioxide levels continue to rise, geothermal energy has emerged as a promising energy alternative to fossil fuels. A barrier to widespread implementation and energy production efficiency is macro-heterogeneity of the rock matrix. Cracks, void spaces, and flow conduits divert fluid flow away from unswept portions of the geothermal reservoir and can cause cooling of the reservoir. Flow heterogeneity has been treated in oil reservoirs by injecting hydrogel particles that travel preferentially to ultra-high permeability zones and selectively block fluid flow in these regions. We are applying polymer hydrogels that withstand hydrothermal conditions of 225 up to 275°C …
Adaptive Parallel Downloader For Large Genomic Datasets, Rasman Mubtasim Swargo
Adaptive Parallel Downloader For Large Genomic Datasets, Rasman Mubtasim Swargo
Miners Solving for Tomorrow Research Conference
Modern next-generation sequencing (NGS) projects routinely generate terabytes of data that researchers download from public repositories such as SRA and ENA. Existing download tools typically employ static concurrency settings, leading to inefficient bandwidth utilization and prolonged download times under dynamic network conditions. We introduce FastBioDL, a parallel downloader for large biological datasets with an adaptive concurrency controller. FastBioDL frames downloading as an online optimization problem, using a utility function and gradient descent to adjust the number of concurrent socket streams during runtime. This approach maximizes throughput while minimizing resource overhead. Evaluations on public genomic datasets show that FastBioDL achieves up …
Introducing Gridtrees For Streaming, Scalable Hierarchical Data Visualization, Nathan Tibbetts
Introducing Gridtrees For Streaming, Scalable Hierarchical Data Visualization, Nathan Tibbetts
Miners Solving for Tomorrow Research Conference
File browsing in the consumer sphere has seen very little advancement in recent years, although attempts have been made to improve upon it. With the goal of multi-level visual file browsing in mind, we present a prototype GridTree, a dynamic, recursive, stable, spatial layout data structure based on subdividing grids, represented as a hierarchy of maps whose granularity increases with depth. We motivate this work with characteristics we have identified as important for viability of a multi-level file-browser, which have become our design goals. We touch on the underlying logic of a GridTree and identify its complexity. We briefly discuss …
Thermal Mirage: Towards Robust Thermal Perception Via Gan-Guided Diffusion, Nuzaer Omar
Thermal Mirage: Towards Robust Thermal Perception Via Gan-Guided Diffusion, Nuzaer Omar
Miners Solving for Tomorrow Research Conference
Thermal object detection systems are critical for safety sensitive applications due to their reliability under adverse conditions. However, existing robustness evaluations in thermal domain primarily focuses on physical or sensor-level perturbations, overlooking vulnerabilities from semantically realistic scene and object manipulations. We introduce Thermal Mirage, a generative framework that leverages GAN-guided diffusion to expose weaknesses in thermal detectors through controlled object and context level perturbations. Our approach learns class-conditional thermal priors via a GAN and uses diffusion to transform object appearances into ambiguous or low-saliency patterns. Simultaneously, a context module degrades scene conditions by simulating harsher night environments. Integrated with a …
Robust Federated Learning With Strategic Adversaries, Manoj Twarakavi
Robust Federated Learning With Strategic Adversaries, Manoj Twarakavi
Miners Solving for Tomorrow Research Conference
Federated Learning (FL) leverages the intelligence of untrusted distributed devices through collaborative training. This makes the training process susceptible to malicious behavior. Existing defense mechanisms largely consider an adversary who attacks a proactive FL server without any adaptability. However, they overlook the presence of a strategic adversary. To address this challenge, our work proposes a Robust Game-theoretic framework where the adversary is both strategic and is equipped with the capability of performing large-scale poisoning attacks.
Harnessing Wavefront Shaping Control For Sensing Applications, Pablo Jara
Harnessing Wavefront Shaping Control For Sensing Applications, Pablo Jara
Miners Solving for Tomorrow Research Conference
Diffuse optical tomography (DOT) and functional near-infrared spectroscopy (fNIRS) enable deep, non-invasive sensing in biological tissue but are fundamentally limited by the photon budget - most injected light is lost to scattering before reaching the detector. Wavefront shaping (WFS) can enhance signal strength inside scattering media via interference, but the conventional diffusion-based sensitivity model breaks down under coherent illumination. We develop a microscopic theory of optical sensitivity that captures interference effects neglected by diffusion theory. We prove analytically that the microscopic and diffusive descriptions coincide under random illumination and identify WFS strategies that enhance sensitivity beyond this limit. The maximum …
Variational Data Assimilation With Steepest Descent Method For Coupled Time-Dependent Stokes-Darcy Model With Bjsj Interface Condition, Yafang Hei
Miners Solving for Tomorrow Research Conference
Variational data assimilation (VDA) determines the initial condition of a dynamical system by minimizing the mismatch between model predictions and observed data. This work studies VDA for the time-dependent Stokes–Darcy system with the BJSJ interface condition. The problem is formulated as a PDE-constrained optimization problem, and the first-order optimality system is derived using the Gâteaux derivative and adjoint variables. A steepest descent method is applied for efficient computation. Spatial and temporal discretizations are carried out using the finite element method and backward Euler scheme, respectively. Numerical results confirm accuracy and convergence.
Dispersive Shock And Rogue Waves In Two-Dimensional Quantum Droplets, Farhana Bristy
Dispersive Shock And Rogue Waves In Two-Dimensional Quantum Droplets, Farhana Bristy
Miners Solving for Tomorrow Research Conference
Quantum droplets, are liquid type configurations stabilized by the balance between attractive mean-field interactions and repulsive quantum fluctuations. They provide highly flexible platforms for the quantum simulation of hydrodynamic phenomena using ultracold gases. Here, we explore the nonlinear quantum dynamics of two-dimensional quantum droplets under Riemann initial conditions. The steepness of the latter facilitates the emergence of radially symmetric dispersive shock waves (DSWs) when quantum fluctuations dominate. In particular, the ensuing DSWs travel from the potential edges toward the center where they collide and through their interference high amplitude spatially localized rogue wave structures emerge. In contrast, tuning the interactions …