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Full-Text Articles in Physical Sciences and Mathematics

Persistent Stealthy Attacks And Their Detection In Large Distributed Cyber-Physical Systems, Simon Bech Thougaard Jan 2022

Persistent Stealthy Attacks And Their Detection In Large Distributed Cyber-Physical Systems, Simon Bech Thougaard

Doctoral Dissertations

"Cyber-Physical Systems (CPS) are increasingly targeted by attackers using a wide and evolving array of methods. When these systems are distributed, every node represents a potential vulnerability, and secure system design must take this into account. Distributed CPSs also have the potential to better detect and handle attacks, by leveraging redundancies of physical measurements between adjacent nodes. The main purpose of this research is to determine the conditions that render a distributed CPS more resistant to attacks, and the conditions that render it more vulnerable. The work is centered around two separate applications: The Smart Grid and Autonomous Drone Swarms. …


Depositional Conditions, Stratigraphic Evolution, And Allo- And Autogenic Controls Of Lower Permian Non-Marine Carbonate Rocks, Lucaogou Low-Order Cycle, Bogda Mountains, Nw China, Yiran Lu Jan 2022

Depositional Conditions, Stratigraphic Evolution, And Allo- And Autogenic Controls Of Lower Permian Non-Marine Carbonate Rocks, Lucaogou Low-Order Cycle, Bogda Mountains, Nw China, Yiran Lu

Doctoral Dissertations

"The overall objective of this study is to interpret the depositional conditions of lacustrine carbonate deposits of the lower Permian Lucaogou low-order cycle in the greater Turpan-Junggar continental rift basin, NW China. The depositional environments of ten carbonate lithofacies in the Tarlong-Taodonggou half graben and the Zhaobishan section were interpreted. Allo- and autogenic factors were identified. They controlled characteristics and distribution pattern of carbonate deposits in regional and local scale, respectively. Allogenic factors include the amount and direction of regional siliciclastic input, basin geometry, cyclic humidity/aridity oscillation, temperature, and regional tectonics. Autogenic factors include local siliciclastic input, local topography, local …


Several Problems In Nonlinear Schrödinger Equations, Tim Van Hoose Jan 2022

Several Problems In Nonlinear Schrödinger Equations, Tim Van Hoose

Masters Theses

“We study several different problems related to nonlinear Schrödinger equations….

We prove several new results for the first equation: a modified scattering result for both an averaged version of the equation and the full equation, as well as a set of Strichartz estimates and a blowup result for the 3d cubic problem.

We also present an exposition of the classical work of Bourgain on invariant measures for the second equation in the mass-subcritical regime”--Abstract, page iv.


Using Lake Sediment Chemistry In The Exploration For Nickel Laterite Deposits In Tropical Regions, Gabriela Yvonne Ramirez Jan 2022

Using Lake Sediment Chemistry In The Exploration For Nickel Laterite Deposits In Tropical Regions, Gabriela Yvonne Ramirez

Masters Theses

"Developing reliable geochemical indicators to guide the search for ore deposits is a long-standing goal. This particularly applies to tropical regions that are often heavily vegetated which hampers boots-on-the ground exploration efforts. Here we present the preliminary results of a study that investigates the usefulness of lake sediment chemistry in the exploration for nickel laterite ore deposits in tropical regions using Lake Izabal, Guatemala, as a case study. Lake Izabal’s catchment area contains Ni laterite deposits along its northern shore, whereas no Ni-laterite discoveries have been made in the south except for a Ni mine in the southern region that …


Particle Swarm Optimization For Critical Experiment Design, Cole Michael Kostelac Jan 2022

Particle Swarm Optimization For Critical Experiment Design, Cole Michael Kostelac

Masters Theses

“Critical experiments are used by nuclear data evaluators and criticality safety engineers to validate nuclear data and computational methods. Many of these experiments are designed to maximize the sensitivity to a certain nuclide-reaction pair in an energy range of interest. Traditionally, a parameter sweep is conducted over a set of experimental variables to find a configuration that is critical and maximally sensitive. As additional variables are added, the total number of configurations increases exponentially and quickly becomes prohibitively computationally expensive to calculate, especially using Monte Carlo methods.

This work presents the development of a particle swarm optimization algorithm to design …


Pressure Relief Wells: Analysis Of Subsurface Heterogeneity To Evaluate Relief Well Locations For Mississippi River Levees, Emma Marie Young Jan 2022

Pressure Relief Wells: Analysis Of Subsurface Heterogeneity To Evaluate Relief Well Locations For Mississippi River Levees, Emma Marie Young

Masters Theses

“When designing pressure relief well systems, it is imperative to understand what major geomorphology and heterogenies features are present, such as buried oxbow lakes, especially when the feature is parallel to the source, such as the Mississippi River. When present, there is a notable greater increase in head pressures, especially on the landward tow of the levee. This can cause erosional features that originally thought of to have been protected from by installing pressure relief wells. When comparing the effective hydraulic conductivities of horizontal clay layers and vertical clay layers spanning the length of the model, little to no noticeable …


Continuous And Discrete Models For Optimal Harvesting In Fisheries, Nagham Abbas Al Qubbanchee Jan 2022

Continuous And Discrete Models For Optimal Harvesting In Fisheries, Nagham Abbas Al Qubbanchee

Masters Theses

"This work focuses on the logistic growth model, where the Gordon-Schaefer model is considered in continuous time. We view the Gordon-Schaefer model as a bioeconomic equation involved in the fishing business, considering biological rates, carrying capacity, and total marginal costs and revenues. In [25], the authors illustrate the analytical solution of the Schaefer model using the integration by parts method and two theorems. The theorems have many assumptions with many different strategies. Due to the nature of the problem, the optimal control system involves many equations and functions, such as the second root of the equation. We concentrate on Theorem …


Lithofacies Characterization Of Marine Shelf Shale And Implicaitons On Depositional Conditions And Processes On The Continental Shelf — A Case Study Of The Upper-Cretaceous Tuscaloosa Marine Shale In Louisiana And Mississippi, U.S.A., Efren Mendez Jr Jan 2022

Lithofacies Characterization Of Marine Shelf Shale And Implicaitons On Depositional Conditions And Processes On The Continental Shelf — A Case Study Of The Upper-Cretaceous Tuscaloosa Marine Shale In Louisiana And Mississippi, U.S.A., Efren Mendez Jr

Masters Theses

"The Upper Cretaceous Tuscaloosa Marine Shale (TMS) is an unconventional shale reservoir deposited on the continental shelf of the northern Gulf of Mexico Basin. Previous studies have focused on sequence stratigraphy, thermal modeling, and well-log correlations. However, a limited understanding of the stratigraphic heterogeneity of the TMS is yet to be studied. This study aims to characterize the stratigraphic heterogeneity of the TMS using core, petrographic, and well-log analyses to better understand the depositional conditions and processes that occur on the continental shelf. The TMS has been classified into four lithofacies of very fine sands – coarse silts (LF1), medium-fine …


Adsorption Of Arsenic Onto River Sediments, Leticia Augusta Dos Santos Ferreira Jan 2022

Adsorption Of Arsenic Onto River Sediments, Leticia Augusta Dos Santos Ferreira

Masters Theses

“Previous studies have noted the relationship between shallow groundwater rich in sodium (Na) and bicarbonate (HCO3) and elevated levels of dissolved arsenic. However, most experimental work on arsenic adsorption in the presence of HCO3 and differing Na/Ca ratios has proven difficult to extrapolate to natural systems because of differences in tested mineral compositions and component concentrations. In this study, I performed a series of adsorption experiments using river sediments to evaluate the influence of HCO3 and monovalent/divalent cations on the extent of arsenic adsorption onto natural sediment in groundwater.

Batch adsorption (kinetics, equilibrium, and metal loading) …


Solvation Of Isoelectronic Halide And Alkali Metal Ions By Argon Atoms, Carly A. Rock, Sarah N. Arradondo, Gregory S. Tschumper Dec 2021

Solvation Of Isoelectronic Halide And Alkali Metal Ions By Argon Atoms, Carly A. Rock, Sarah N. Arradondo, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work systematically examines the interactions of alkali metal cations and their isoelectronic halide counterparts with up to six solvating Ar atoms (M+Arn and X–Arn, where M = Li, Na, K, and Rb; X = H, F, Cl, and Br; and n = 1–6) via full geometry optimizations with the MP2 method and robust, correlation-consistent quadruple-ζ (QZ) basis sets. 116 unique M+Arn and X–Arn stationary points have been characterized on the MP2/QZ potential energy surface. To the best of our knowledge, approximately two dozen of these stationary points have been reported here for the first time. Some of these new …


Oscillation Of Nonlinear Third-Order Difference Equations With Mixed Neutral Terms, Jehad Alzabut, Martin Bohner, Said R. Grace Dec 2021

Oscillation Of Nonlinear Third-Order Difference Equations With Mixed Neutral Terms, Jehad Alzabut, Martin Bohner, Said R. Grace

Mathematics and Statistics Faculty Research & Creative Works

In this paper, new oscillation results for nonlinear third-order difference equations with mixed neutral terms are established. Unlike previously used techniques, which often were based on Riccati transformation and involve limsup or liminf conditions for the oscillation, the main results are obtained by means of a new approach, which is based on a comparison technique. Our new results extend, simplify, and improve existing results in the literature. Two examples with specific values of parameters are offered.


Fourth Derivative Singularly P-Stable Method For The Numerical Solution Of The Schrödinger Equation, Ali Shokri, Higinio Ramos, Mohammad Mehdizadeh Khalsaraei, Fikret A. Aliev, Martin Bohner Dec 2021

Fourth Derivative Singularly P-Stable Method For The Numerical Solution Of The Schrödinger Equation, Ali Shokri, Higinio Ramos, Mohammad Mehdizadeh Khalsaraei, Fikret A. Aliev, Martin Bohner

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we construct a method with eight steps that belongs to the family of Obrechkoff methods. Due to the explicit nature of the new method, not only does it not require another method as predictor, but it can also be considered as a suitable predictive technique to be used with implicit methods. Periodicity and error terms are studied when applied to solve the radial Schrödinger equation, considering different energy levels. We show its advantages in terms of accuracy, consistency, and convergence in comparison with other methods of the same order appearing in the literature.


Understanding The Multiple Small Magnitude Induced Seismic Soil Fatigue Potential On Hazard Assessments, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz Dec 2021

Understanding The Multiple Small Magnitude Induced Seismic Soil Fatigue Potential On Hazard Assessments, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Soils under spacio-temporally clustered events loading are susceptible to soil fatigue as pore pressure dissipates and the soil is unable to recover. This potential for damage from soil fatigue is identified through an induced seismic fatigue equation provided in this paper. The objective of this paper is to present an induced seimic equation for soils under spacio-temporally clustered impulse loading to identify potential hazards to the subsurface that supports critical infrastructure. It further illustrates the use of the equation as determined from a comparison of three varying soil profiles with resulting data that shows a need to establish new critieria …


Enhancing Gravitational-Wave Science With Machine Learning, Elena Cuoco, Jade Powell, Marco Cavaglia, Kendall Ackley, For Full List Of Authors, See Publisher's Website. Dec 2021

Enhancing Gravitational-Wave Science With Machine Learning, Elena Cuoco, Jade Powell, Marco Cavaglia, Kendall Ackley, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Machine learning has emerged as a popular and powerful approach for solving problems in astrophysics. We review applications of machine learning techniques for the analysis of ground-based gravitational-wave (GW) detector data. Examples include techniques for improving the sensitivity of Advanced Laser Interferometer GW Observatory and Advanced Virgo GW searches, methods for fast measurements of the astrophysical parameters of GW sources, and algorithms for reduction and characterization of non-astrophysical detector noise. These applications demonstrate how machine learning techniques may be harnessed to enhance the science that is possible with current and future GW detectors.


Anomalous Normal Fluid Response In A Chiral Superconductor Ute₂, Seokjin Bae, Hyunsoo Kim, Yun Suk Eo, Sheng Ran, I. Lin Liu, Wesley T. Fuhrman, Johnpierre Paglione, Nicholas P. Butch, Steven M. Anlage Dec 2021

Anomalous Normal Fluid Response In A Chiral Superconductor Ute₂, Seokjin Bae, Hyunsoo Kim, Yun Suk Eo, Sheng Ran, I. Lin Liu, Wesley T. Fuhrman, Johnpierre Paglione, Nicholas P. Butch, Steven M. Anlage

Physics Faculty Research & Creative Works

Chiral superconductors have been proposed as one pathway to realize Majorana normal fluid at its boundary. However, the long-sought 2D and 3D chiral superconductors with edge and surface Majorana normal fluid are yet to be conclusively found. Here, we report evidence for a chiral spin-triplet pairing state of UTe2 with surface normal fluid response. The microwave surface impedance of the UTe2 crystal was measured and converted to complex conductivity, which is sensitive to both normal and superfluid responses. The anomalous residual normal fluid conductivity supports the presence of a significant normal fluid response. The superfluid conductivity follows the …


Molecular Structure Retrieval Directly From Laboratory-Frame Photoelectron Spectra In Laser-Induced Electron Diffraction, A. Sanchez, K. Amini, S. J. Wang, T. Steinle, B. Belsa, J. Danek, Anh-Thu Le, For Full List Of Authors, See Publisher's Website. Dec 2021

Molecular Structure Retrieval Directly From Laboratory-Frame Photoelectron Spectra In Laser-Induced Electron Diffraction, A. Sanchez, K. Amini, S. J. Wang, T. Steinle, B. Belsa, J. Danek, Anh-Thu Le, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Ubiquitous to most molecular scattering methods is the challenge to retrieve bond distance and angle from the scattering signals since this requires convergence of pattern matching algorithms or fitting methods. This problem is typically exacerbated when imaging larger molecules or for dynamic systems with little a priori knowledge. Here, we employ laser-induced electron diffraction (LIED) which is a powerful means to determine the precise atomic configuration of an isolated gas-phase molecule with picometre spatial and attosecond temporal precision. We introduce a simple molecular retrieval method, which is based only on the identification of critical points in the oscillating molecular interference …


Triply Differential Positron And Electron Impact Ionization Of Argon: Systematic Features And Scaling, Robert D. Dubois, O. G. De Lucio Dec 2021

Triply Differential Positron And Electron Impact Ionization Of Argon: Systematic Features And Scaling, Robert D. Dubois, O. G. De Lucio

Physics Faculty Research & Creative Works

Triply differential data are presented for the 200 eV positron and electron impact ionization of argon. Six electron emission energies between 2.6 and 19 eV, and for scattering angles of 2, 3, and 4 degrees cover a momentum transfer range of 0.16 to 0.31 a.u. The binary and recoil intensities are fitted using a double peak structure in both regions, which, for the present kinematic conditions, are unresolved. The fitted peak intensities and angular positions are shown to have systematic dependences as a function of the momentum transfer and kinematic emission angle, respectively, and illustrate projectile charge effects. A comparison …


Formation And Quench Of Homonuclear And Heteronuclear Quantum Droplets In One Dimension, Simeon I. Mistakidis, T. Mithun, P. G. Kevrekidis, H. R. Sadeghpour, P. Schmelcher Dec 2021

Formation And Quench Of Homonuclear And Heteronuclear Quantum Droplets In One Dimension, Simeon I. Mistakidis, T. Mithun, P. G. Kevrekidis, H. R. Sadeghpour, P. Schmelcher

Physics Faculty Research & Creative Works

We Study The Impact Of Beyond Lee-Huang-Yang (LHY) Physics, Especially Due To Intercomponent Correlations, In The Ground State And The Quench Dynamics Of One-Dimensional Quantum Droplets With An Ab Initio Nonperturbative Approach. It Is Found That The Droplet Gaussian-Shaped Configuration Arising For Intercomponent Attractive Couplings Becomes Narrower For Stronger Intracomponent Repulsion And Transits Towards A Flat-Top Structure Either For Larger Particle Numbers Or Weaker Intercomponent Attraction. Additionally, A Harmonic Trap Prevents The Flat-Top Formation. At The Balance Point Where Mean-Field Interactions Cancel Out, We Show That A Correlation Hole Is Present In The Few-Particle Limit Of LHY Fluids As Well …


Fingerprinting The Cretaceous-Paleogene Boundary Impact With Zn Isotopes, Ryan Mathur, Brandon Mahan, Marissa Spencer, Linda Godfrey, Neil Landman, Matthew Garb, D. Graham Pearson, Sheng-Ao Liu, Francisca Oboh-Ikuenobe Dec 2021

Fingerprinting The Cretaceous-Paleogene Boundary Impact With Zn Isotopes, Ryan Mathur, Brandon Mahan, Marissa Spencer, Linda Godfrey, Neil Landman, Matthew Garb, D. Graham Pearson, Sheng-Ao Liu, Francisca Oboh-Ikuenobe

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Numerous geochemical anomalies exist at the K-Pg boundary that indicate the addition of extraterrestrial materials; however, none fingerprint volatilization, a key process that occurs during large bolide impacts. Stable Zn isotopes are an exceptional indicator of volatility-related processes, where partial vaporization of Zn leaves the residuum enriched in its heavy isotopes. Here, we present Zn isotope data for sedimentary rock layers of the K-Pg boundary, which display heavier Zn isotope compositions and lower Zn concentrations relative to surrounding sedimentary rocks, the carbonate platform at the impact site, and most carbonaceous chondrites. Neither volcanic events nor secondary alteration during weathering and …


Resilient Error-Bounded Lossy Compressor For Data Transfer, Sihuan Li, Sheng Di, Kai Zhao, Xin Liang, Zizhong Chen, Franck Cappello Nov 2021

Resilient Error-Bounded Lossy Compressor For Data Transfer, Sihuan Li, Sheng Di, Kai Zhao, Xin Liang, Zizhong Chen, Franck Cappello

Computer Science Faculty Research & Creative Works

Todays exa-scale scientific applications or advanced instruments are producing vast volumes of data, which need to be shared/transferred through the network/devices with relatively low bandwidth (e.g., data sharing on WAN or transferring from edge devices to supercomputers). Lossy compression is one of the candidate strategies to address the big data issue. However, little work was done to make it resilient against silent errors, which may happen during the stage of compression or data transferring. In this paper, we propose a resilient error-bounded lossy compressor based on the SZ compression framework. Specifically, we design a new independentblock-wise model that decomposes the …


Reducing Kidney Discard With Artificial Intelligence Decision Support: The Need For A Transdisciplinary Systems Approach, Richard Threlkeld, Lirim Ashiku, Casey I. Canfield, Daniel Burton Shank, Mark A. Schnitzler, Krista L. Lentine, David A. Axelrod, Anil Choudary Reddy Battineni, Henry Randall, Cihan H. Dagli Nov 2021

Reducing Kidney Discard With Artificial Intelligence Decision Support: The Need For A Transdisciplinary Systems Approach, Richard Threlkeld, Lirim Ashiku, Casey I. Canfield, Daniel Burton Shank, Mark A. Schnitzler, Krista L. Lentine, David A. Axelrod, Anil Choudary Reddy Battineni, Henry Randall, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Purpose of Review: A transdisciplinary systems approach to the design of an artificial intelligence (AI) decision support system can more effectively address the limitations of AI systems. By incorporating stakeholder input early in the process, the final product is more likely to improve decision-making and effectively reduce kidney discard.

Recent Findings: Kidney discard is a complex problem that will require increased coordination between transplant stakeholders. An AI decision support system has significant potential, but there are challenges associated with overfitting, poor explainability, and inadequate trust. A transdisciplinary approach provides a holistic perspective that incorporates expertise from engineering, social science, and …


Learning Transfers Via Transfer Learning, Md Arifuzzaman, Engin Arslan Nov 2021

Learning Transfers Via Transfer Learning, Md Arifuzzaman, Engin Arslan

Computer Science Faculty Research & Creative Works

Detecting performance anomalies is key to efficiently utilize network resources and improve the quality of service. Researchers proposed various approaches to identify the presence of anomalies by analyzing performance statistics using heuristic (e.g., change point detection) and Machine Learning (ML) models. Although these models yield high accuracy in the networks that they are trained for, their performance degrade severely when transferred to different network settings. This is because of the fact that existing models detect anomalies by capturing the changes in transfer throughput and observed RTT values, which are dependent to network settings. In this paper, we propose a novel …


Online Optimization Of File Transfers In High-Speed Networks, Md Arifuzzaman, Engin Arslan Nov 2021

Online Optimization Of File Transfers In High-Speed Networks, Md Arifuzzaman, Engin Arslan

Computer Science Faculty Research & Creative Works

File transfers in high-speed networks require network and I/O parallelism to reach high speeds, however, creating arbitrarily large numbers of I/O and network threads overwhelms system resources and causes fairness issues. In this paper, we introduce Falcon that combines a novel utility function with state-of-the-art online optimization algorithms to discover the degree of I/O and network parallelism for file transfer that can maximize the throughput while keeping system overhead low and ensuring fairness among competing transfers. Our extensive evaluations in several dedicated and production high-speed networks show that Falcon can find near optimal solution in as little as 20 seconds …


Detecting And Reconstructing Gravitational Waves From The Next Galactic Core-Collapse Supernova In The Advanced Detector Era, Marek J. Szczepańczyk, Javier M. Antelis, Michael Benjamin, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Nov 2021

Detecting And Reconstructing Gravitational Waves From The Next Galactic Core-Collapse Supernova In The Advanced Detector Era, Marek J. Szczepańczyk, Javier M. Antelis, Michael Benjamin, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We performed a detailed analysis of the detectability of a wide range of gravitational waves derived from core-collapse supernova simulations using gravitational-wave detector noise scaled to the sensitivity of the upcoming fourth and fifth observing runs of the Advanced LIGO, Advanced Virgo, and KAGRA. We use the coherent WaveBurst algorithm, which was used in the previous observing runs to search for gravitational waves from core-collapse supernovae. As coherent WaveBurst makes minimal assumptions on the morphology of a gravitational-wave signal, it can play an important role in the first detection of gravitational waves from an event in the Milky Way. We …


Experimental Verification Of Principal Losses In A Regulatory Particulate Matter Emissions Sampling System For Aircraft Turbine Engines, D. B. Kittelson, J. Swanson, M. Aldridge, R. A. Giannelli, J. S. Kinsey, J. A. Stevens, D. S. Liscinsky, Donald E. Hagen, For Full List Of Authors, See Publisher's Website. Nov 2021

Experimental Verification Of Principal Losses In A Regulatory Particulate Matter Emissions Sampling System For Aircraft Turbine Engines, D. B. Kittelson, J. Swanson, M. Aldridge, R. A. Giannelli, J. S. Kinsey, J. A. Stevens, D. S. Liscinsky, Donald E. Hagen, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

A sampling system for measuring emissions of nonvolatile particulate matter (nvPM) from aircraft gas turbine engines has been developed to replace the use of smoke number and is used for international regulatory purposes. This sampling system can be up to 35 m in length. The sampling system length in addition to the volatile particle remover (VPR) and other sampling system components lead to substantial particle losses, which are a function of the particle size distribution, ranging from 50 to 90% for particle number concentrations and 10-50% for particle mass concentrations. The particle size distribution is dependent on engine technology, operating …


Magnetic Dichroism In Few-Photon Ionization Of Polarized Atoms, B. P. Acharya, M. Dodson, S. Dubey, K. L. Romans, A. H.N.C. De Silva, K. Foster, O. Russ, K. Bartschat, N. Douguet, Daniel Fischer Nov 2021

Magnetic Dichroism In Few-Photon Ionization Of Polarized Atoms, B. P. Acharya, M. Dodson, S. Dubey, K. L. Romans, A. H.N.C. De Silva, K. Foster, O. Russ, K. Bartschat, N. Douguet, Daniel Fischer

Physics Faculty Research & Creative Works

We consider few-photon ionization of atomic lithium by linearly polarized femtosecond laser pulses and demonstrate that asymmetries of the electron angular distribution can occur for initially polarized (2p, m=+1) target atoms. The dependence of the photoelectron emission angle relative to the electric field direction is investigated at different laser intensities and wavelengths. The experimental spectra show excellent agreement with numerical solutions of the time-dependent Schrödinger equation. In the perturbative picture, the angular shift is traced back to interferences between partial waves with mean magnetic quantum number (m)≠0. This observation allows us to obtain quantum mechanical information on the final electronic …


Correcting Correlation Functions For Redshift-Dependent Interloper Contamination, Daniel J. Farrow, Ariel G. Sánchez, Robin Ciardullo, Shun Saito, For Full List Of Authors, See Publisher's Website. Nov 2021

Correcting Correlation Functions For Redshift-Dependent Interloper Contamination, Daniel J. Farrow, Ariel G. Sánchez, Robin Ciardullo, Shun Saito, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The construction of catalogues of a particular type of galaxy can be complicated by interlopers contaminating the sample. In spectroscopic galaxy surveys this can be due to the misclassification of an emission line; for example in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) low-redshift [O ii] emitters may make up a few per cent of the observed Ly α emitter (LAE) sample. The presence of contaminants affects the measured correlation functions and power spectra. Previous attempts to deal with this using the cross-correlation function have assumed sources at a fixed redshift, or not modelled evolution within the adopted redshift bins. …


Apportioning Deformation Among Depth Intervals In An Aquifer System Using Insar And Head Data, Ryan G. Smith, Hossein Hashemi, Jingyi Chen, Rosemary Knight Nov 2021

Apportioning Deformation Among Depth Intervals In An Aquifer System Using Insar And Head Data, Ryan G. Smith, Hossein Hashemi, Jingyi Chen, Rosemary Knight

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Land surface subsidence due to excessive groundwater pumping is an increasing concern in California, USA. Interferometric Synthetic Aperture Radar (InSAR) is a remote sensing technique for measuring centimeter-to-millimeter surface deformation at 10-100 m spatial resolution. Here, a data-driven approach that attributes deformation to individual depth intervals within an aquifer system by integrating head data acquired from each of three screened intervals in a monitoring well with InSAR surface deformation measurements was developed. The study area was the Colusa Basin in northern Central Valley. To reconstruct the surface deformation history over the study area, 13 ALOS-PALSAR scenes acquired between 2006 and …


Systematic Evaluation Of A Novel Self-Healing Poly(Acrylamide-Co-Vinyl Acetate)/Alginate Polymer Gel For Fluid Flow Control In High Temperature And High Salinity Reservoirs, Jingyang Pu, Baojun Bai, Thomas P. Schuman Oct 2021

Systematic Evaluation Of A Novel Self-Healing Poly(Acrylamide-Co-Vinyl Acetate)/Alginate Polymer Gel For Fluid Flow Control In High Temperature And High Salinity Reservoirs, Jingyang Pu, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Preferential fluid flow often occurs when water and CO2 is injected into mature oilfields, sig-nificantly reducing their injection efficiency. Particle gels have been evaluated and applied to control the short circulation problems. This study systematically investigated a novel poly(acrylamide-co-vinyl acetate)/alginate-based interpenetrated gel system (Alg-IPNG) which is designed to control the preferential fluid flow problems in high-temperature reservoirs. Chromium acetate was incorporated into the gel system to provide the delayed crosslinking feature of the particle gels. The alginate polymer system can also take advantage of the Ca2+ ions in the formation water, which exist in most reservoirs, to reinforce …


Towards Generalizable Network Anomaly Detection Models, Md Arifuzzaman, Shafkat Islam, Engin Arslan Oct 2021

Towards Generalizable Network Anomaly Detection Models, Md Arifuzzaman, Shafkat Islam, Engin Arslan

Computer Science Faculty Research & Creative Works

Finding the root causes of network performance anomalies is critical to satisfy the quality-of-service requirements. In this paper, we introduce machine learning (ML) models to process TCP socket statistics to pinpoint underlying reasons of performance issues such as packet loss and jitter. More importantly, we introduce a novel feature engineering method to transform network-dependent metrics (e.g., total packet count and round-trip time) in training datasets into network independent forms to be able to transfer the models to new network settings without requiring retraining them. Experimental results in various network settings show that the proposed feature engineering approach improves the performance …