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Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen Jul 2020

Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel adaptive neural network (NN) based distributed state estimation scheme for a heterogeneous sensor network (HSN), to estimate the state vector of an unknown nonlinear process/target by using sensed output when the target input remains unknown. The active nodes in the HSN can sense the target output based on the detection range. By using a connected graph, the active nodes will communicate their estimated state vector from their adaptive NN observer to other passive nodes in the neighborhood that cannot sense the target, so that they can estimate the target state vector. Next, a subset of …


Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi Jul 2020

Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave and millimeter wave synthetic aperture radar (SAR) imaging techniques are commonly used to generate high-resolution qualitative images showing the reflectivity (or complex permittivity) contrast in a sample-under-test (SUT). These techniques have been successfully applied for many diverse applications. However, these images lack quantitative information about the SUT, namely, its complex permittivity distribution. In this article, a novel method to extract the spatial distribution of complex permittivity from SAR images is proposed. The principle of the proposed method is outlined, then verified by a series of electromagnetic simulations, demonstrating that the proposed method can accurately extract the complex permittivity. Additionally, …


Online Optimal Adaptive Control Of A Class Of Uncertain Nonlinear Discrete-Time Systems, Rohollah Moghadam, Pappa Natarajan, Krishnan Raghavan, Sarangapani Jagannathan Jul 2020

Online Optimal Adaptive Control Of A Class Of Uncertain Nonlinear Discrete-Time Systems, Rohollah Moghadam, Pappa Natarajan, Krishnan Raghavan, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a multi-layer neural network (MNN) based online optimal adaptive regulation of a class of nonlinear discrete-time systems in affine form with uncertain internal dynamics is introduced. The multi-layer neural networks (MNN)-based actor-critic framework is utilized to estimate the optimal control input and cost function. The temporal difference (TD) error is derived from the difference between actual and estimated cost function. The MNN weights of both critic and actor are tuned at every sampling instant as a function of the instantaneous temporal difference and control policy errors. The proposed approach does not require the selection of any basis …


Dynamic Trajectory Generation And A Robust Controller To Intercept A Moving Ball In A Game Setting, Ravi Prakash, Laxmidhar Behera, Santhakumar Mohan, Sarangapani Jagannathan Jul 2020

Dynamic Trajectory Generation And A Robust Controller To Intercept A Moving Ball In A Game Setting, Ravi Prakash, Laxmidhar Behera, Santhakumar Mohan, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Complex and interactive robot manipulation skills, such as playing a game of table tennis against a human opponent, are a novel problem with multifaceted challenges. Accurate dynamic trajectory generation in order to respond to the tennis ball from the opponent and a novel control scheme for robust and high-performance tracking of the ball in such dynamic situations is a prerequisite to winning the game. In this paper, the dynamic movement primitives (DMPs) are employed for the stable generation of dynamic trajectories in the presence of environmental uncertainties such as ball position and velocity, opponent position and velocity and so on. …


Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta Jun 2020

Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta

Physics Faculty Research & Creative Works

All vertebrate brains contain a dense matrix of thin fibers that release serotonin (5-hydroxytryptamine), a neurotransmitter that modulates a wide range of neural, glial, and vascular processes. Perturbations in the density of this matrix have been associated with a number of mental disorders, including autism and depression, but its self-organization and plasticity remain poorly understood. We introduce a model based on reflected Fractional Brownian Motion (FBM), a rigorously defined stochastic process, and show that it recapitulates some key features of regional serotonergic fiber densities. Specifically, we use supercomputing simulations to model fibers as FBM-paths in two-dimensional brain-like domains and demonstrate …


Mobile Manipulating Drones, Paul Oh Jun 2020

Mobile Manipulating Drones, Paul Oh

INSPIRE Archived Webinars

In the past few years, robotic limbs have been attached to rotorcraft drones to perform aerial manipulation. Unlike simple object pick-and-place, such mobile-manipulating drones are dexterous to perform tasks like valve-turning, hatch-opening, and tool-handling. This is a paradigm shift where such drones actively interact with their environment rather than just passively surveil. Aerial manipulation is challenging because such interaction yields reaction forces and torques that destabilize the drone. This talk will provide an overview of aerial manipulation and showcase examples that could serve in infrastructure inspection, maintenance, and repair.


Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website. Jun 2020

Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

A state of matter with a multi-component order parameter can give rise to vestigial order. In the vestigial phase, the primary order is only partially melted, leaving a remaining symmetry breaking behind, an effect driven by strong classical or quantum fluctuations. Vestigial states due to primary spin and charge-density-wave order have been discussed in iron-based and cuprate materials. Here we present the observation of a partially melted superconductivity in which pairing fluctuations condense at a separate phase transition and form a nematic state with broken Z3, i.e., three-state Potts-model symmetry. Thermal expansion, specific heat and magnetization measurements of …


Vanishing Porosity Limit Of The Coupled Stokes-Brinkman System, Mingwen Fei, Dongjuan Niu, Xiaoming Wang Jun 2020

Vanishing Porosity Limit Of The Coupled Stokes-Brinkman System, Mingwen Fei, Dongjuan Niu, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

We investigate the small porosity asymptotic behavior of the coupled Stokes-Brinkman system in the presence of a curved interface between the Stokes region and the Brinkman region. in particular, we derive a set of approximate solutions, validated via rigorous analysis, to the coupled Stokes-Brinkman system. of particular interest is that the approximate solution satisfies a generalized Beavers-Joseph-Saffman-Jones interface condition (1.9) with the constant of proportionality independent of the curvature of the interface.


Motifs Enable Communication Efficiency And Fault-Tolerance In Transcriptional Networks, Satyaki Roy, Preetam Ghosh, Dipak Barua, Sajal K. Das Jun 2020

Motifs Enable Communication Efficiency And Fault-Tolerance In Transcriptional Networks, Satyaki Roy, Preetam Ghosh, Dipak Barua, Sajal K. Das

Computer Science Faculty Research & Creative Works

Analysis of the topology of transcriptional regulatory networks (TRNs) is an effective way to study the regulatory interactions between the transcription factors (TFs) and the target genes. TRNs are characterized by the abundance of motifs such as feed forward loops (FFLs), which contribute to their structural and functional properties. In this paper, we focus on the role of motifs (specifically, FFLs) in signal propagation in TRNs and the organization of the TRN topology with FFLs as building blocks. To this end, we classify nodes participating in FFLs (termed motif central nodes) into three distinct roles (namely, roles A, B …


Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin Jun 2020

Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin

Physics Faculty Research & Creative Works

For a long time, the predictive limits of perturbative quantum field theory have been limited by our inability to carry out loop calculations to an arbitrarily high order, which become increasingly complex as the order of perturbation theory is increased. This problem is exacerbated by the fact that perturbation series derived from loop diagram (Feynman diagram) calculations represent asymptotic (divergent) series which limits the predictive power of perturbative quantum field theory. Here, we discuss an ansatz that could overcome these limits, based on the observations that (i) for many phenomenologically relevant field theories, one can derive dispersion relations which relate …


Handling Missing Data For Unsupervised Learning With An Application On A Fitbir Traumatic Brain Injury (Tbi) Dataset, Louis Steinmeister, Dacosta Yeboah, Gayla Olbricht, Tayo Obafemi-Ajayi, Bassam Hadi, Daniel Hier, Donald C. Wunsch Jun 2020

Handling Missing Data For Unsupervised Learning With An Application On A Fitbir Traumatic Brain Injury (Tbi) Dataset, Louis Steinmeister, Dacosta Yeboah, Gayla Olbricht, Tayo Obafemi-Ajayi, Bassam Hadi, Daniel Hier, Donald C. Wunsch

Mathematics and Statistics Faculty Research & Creative Works

"The problem of missing data and imputation have been widely discussed amongst specialists. However, many data scientists and applied statisticians fail to appropriately consider this issue. Often, it seems intuitive to discard observations containing missing data or simply to substitute means. This can lead to disastrous consequences, particularly in an era of exponentially increasing data volumes. In the following, we show how inappropriate handling of missing data and an insufficient analysis of the censoring mechanism can lead to a bias, overconfidence in the estimation of parameters, could challenge the reproducibility of obtained results, and may distort the structure of the …


Effect Of Secondary Electron Emission On The Guiding Properties Of Insulating Capillaries, E. Giglio, K. Tökési, Robert D. Dubois Jun 2020

Effect Of Secondary Electron Emission On The Guiding Properties Of Insulating Capillaries, E. Giglio, K. Tökési, Robert D. Dubois

Physics Faculty Research & Creative Works

The transmission of 1 keV Ar+ ions through a macroscopic glass capillary is simulated by taking explicitly into account the secondary electron (SE) emission generated by ion impacts inside the capillary. The SE emission re-distributes the injected charge in the capillary wall and thus modifies the guiding power of insulating capillaries. Especially for high beam intensities, SE are found to be crucial for explaining the observed time-evolution of the transmitted intensities.


Fully Differential Study Of Ionization Of H2 By P Impact Near Velocity Matching, M. Dhital, S. Bastola, A. Silvus, A. Hasan, B. R. Lamichhane, E. Ali, M. F. Ciappina, R. A. Lomsadze, D. Cikota, B. Boggs, Don H. Madison, Michael Schulz Jun 2020

Fully Differential Study Of Ionization Of H2 By P Impact Near Velocity Matching, M. Dhital, S. Bastola, A. Silvus, A. Hasan, B. R. Lamichhane, E. Ali, M. F. Ciappina, R. A. Lomsadze, D. Cikota, B. Boggs, Don H. Madison, Michael Schulz

Physics Faculty Research & Creative Works

Fully differential cross sections (FDCS) for ionization in p + H2 collisions in the region of the electron-projectile velocity matching were measured and calculated. The FDCS were found to be very sensitive to the details of the few-body dynamics underlying the reaction.


Cross Section Scaling For The Ionization Of H2o By Highly Charged Ions, N. Bachi, S. Otranto, Ronald E. Olson Jun 2020

Cross Section Scaling For The Ionization Of H2o By Highly Charged Ions, N. Bachi, S. Otranto, Ronald E. Olson

Physics Faculty Research & Creative Works

A classical trajectory Monte Carlo model that explicitly considers the ten electrons of the H2O molecule is used to study electron production in collisions involving bare ions. Present results are contrasted to the reported experimental data and to other theoretical results obtained by means of distorted wave models. Focus is made on the energy range 100 (keV/amu) /ZP-1000 (keV/amu)/ZP along which a simple scaling for the net cross section is introduced.


A Quantitative Study Of Ion Guiding Between Two Glass Plates, Robert D. Dubois, E. Giglio, K. Tőkési Jun 2020

A Quantitative Study Of Ion Guiding Between Two Glass Plates, Robert D. Dubois, E. Giglio, K. Tőkési

Physics Faculty Research & Creative Works

The transmission of a 1 keV Ar+ beam between two glass plates was studied. We present experimental data with the goal to provide quantitative information about the buildup and decay of charge on the glass plates and how this correlates with the observed guiding.


The Role Of Multiple Ionization In Fast Highly Charged Ions Collisions On H2o, N. Bachi, G. S. Otero, S. Otranto, Ronald E. Olson Jun 2020

The Role Of Multiple Ionization In Fast Highly Charged Ions Collisions On H2o, N. Bachi, G. S. Otero, S. Otranto, Ronald E. Olson

Physics Faculty Research & Creative Works

An adaptive classical trajectory Monte Carlo model that explicitly considers the eight electrons corresponding to the valence molecular orbitals of the H2O molecule is introduced. In this dynamical model, the electrons' binding energies change throughout the collision ensuring the proper energy deposition by the projectile for multiple electron removal. Present results are relevant to the ion-therapy program, specially at irradiation planning stages in which detailed information on the electronic emission spectra are needed as input data.


Triple Differential Cross Sections For Electron Impact Ionization Of Methane At Intermediate Energy, C. Granados, E. Ali, A. Sakaamini, M. Harvey, L. U. Ancarani, A. J. Murray, M. Dogan, C. Ning, J. Colgan, Don H. Madison Jun 2020

Triple Differential Cross Sections For Electron Impact Ionization Of Methane At Intermediate Energy, C. Granados, E. Ali, A. Sakaamini, M. Harvey, L. U. Ancarani, A. J. Murray, M. Dogan, C. Ning, J. Colgan, Don H. Madison

Physics Faculty Research & Creative Works

In a joint experimental and theoretical collaboration, triple differential cross sections are presented for electron-impact single ionization of the 1t2 and 2a1 states of CH4 at an incident electron energy of 250 eV. Experimental data from two different laboratories are compared with molecular 3-body distorted wave (M3DW) and generalized Sturmian function (GSF) calculations. Overall, we find a good experiment-experiment, and also a relatively good experiment-theories, agreement. We observe that for the 1t2 state, similarly to ionization of atomic p-states, the peak is sometimes doubled.


New Structures In Fully Differential Cross Sections For Ionization Of He By Proton Impact, M. Dhital, S. Bastola, A. Silvus, A. Hasan, B. R. Lamichhane, E. Ali, M. F. Ciappina, R. A. Lomsadze, Don H. Madison, Michael Schulz Jun 2020

New Structures In Fully Differential Cross Sections For Ionization Of He By Proton Impact, M. Dhital, S. Bastola, A. Silvus, A. Hasan, B. R. Lamichhane, E. Ali, M. F. Ciappina, R. A. Lomsadze, Don H. Madison, Michael Schulz

Physics Faculty Research & Creative Works

Fully differential cross sections (FDCS) for ionization in p + He collisions were measured and calculated for several projectile energy losses. The electron angular dependence of the FDCS reveals structures not seen in previous studies.


Energy Dependent Relative Cross Sections In Carbon 1s Photoionization, Michael Schulz, A. Hasan, B. Lamichhane, T. Arthanayaka, M. Dhital, S. Bastola, D. Céolin, C. Nicolas, T. Marchenko, G. Goldsztejn, L. Journel, R. Guillemin, T. X. Carroll, K. J. Børve Jun 2020

Energy Dependent Relative Cross Sections In Carbon 1s Photoionization, Michael Schulz, A. Hasan, B. Lamichhane, T. Arthanayaka, M. Dhital, S. Bastola, D. Céolin, C. Nicolas, T. Marchenko, G. Goldsztejn, L. Journel, R. Guillemin, T. X. Carroll, K. J. Børve

Physics Faculty Research & Creative Works

Synopsis We demonstrate that the possibility of monitoring relative photoionization cross sections over a large photon energy range extending to hard x-rays allows studying and disentangling shake processes and intramolecular inelastic scattering effects. An "EXAFS"-type of oscillatory behavior of the relative C 1s cross sections is observed in a wide photon energy range up to 1 keV due to multiple intramolecular elastic scattering of the photoelectron. These effects are also present in solids and constitute a significant part of all elastic and inelastic scattering effects occurring in solids.


Anchoring The Hydrogen Sulfide Dimer Potential Energy Surface To Juxtapose (H2s)2 With (H2o)2, Morgan A. Perkins, Kayleigh R. Barlow, Katelyn M. Dreux, Gregory S. Tschumper Jun 2020

Anchoring The Hydrogen Sulfide Dimer Potential Energy Surface To Juxtapose (H2s)2 With (H2o)2, Morgan A. Perkins, Kayleigh R. Barlow, Katelyn M. Dreux, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

Twelve stationary points have been characterized on the (H2S)2 potential energy surface using the MP2 and CCSD(T) methods with large, correlation consistent basis sets. To the best of our knowledge, five of the structures have not been identified elsewhere and are presented here for the first time. A similar analysis was performed on the ten, well-known structures of the water dimer in order to facilitate direct comparisons between the corresponding (H2O)2 and (H2S)2 configurations. Harmonic vibrational frequency computations identify three (H2S)2 configurations as minima, four as transition states, …


Bi-Annual Activity Report Center For Advancing Faculty Excellence: Fall 2018-Spring 2020, Missouri University Of Science And Technology Jun 2020

Bi-Annual Activity Report Center For Advancing Faculty Excellence: Fall 2018-Spring 2020, Missouri University Of Science And Technology

CAFE Annual Activity Reports

No abstract provided.


A Minimal Congruence Lattice Representation For 𝕄ₚ₊₁, Roger Bunn, David E. Grow, Matt Insall, Philip Thiem Jun 2020

A Minimal Congruence Lattice Representation For 𝕄ₚ₊₁, Roger Bunn, David E. Grow, Matt Insall, Philip Thiem

Mathematics and Statistics Faculty Research & Creative Works

Let p be an odd prime. The unary algebra consisting of the dihedral group of order 2p, acting on itself by left translation, is a minimal congruence lattice representation of 𝕄p+1.


Proof-Of-Activity Consensus Protocol Based On A Network's Active Nodes, Roman Belfer, Antonina Kashtalian, Andrii Nicheporuk, George Markowsky, Anatoliy Sachenko Jun 2020

Proof-Of-Activity Consensus Protocol Based On A Network's Active Nodes, Roman Belfer, Antonina Kashtalian, Andrii Nicheporuk, George Markowsky, Anatoliy Sachenko

Computer Science Faculty Research & Creative Works

The paper proposes a new socially oriented protocol that avoids pseudo-decentralization and monopolization of the network, increases the availability of the system, provides a fair selection of potential validator nodes, and provides a fair reward for creating new blocks and adding them to the blockchain. Our proposed protocol provides for the creation and addition of new blocks to a blockchain. Defines a node validator, which will create the next block according to its useful activity in the network according to predefined conditions, which can be formed according to the requirements of the system and will satisfy the individual needs of …


Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz Jun 2020

Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Current studies that focus solely on the cause of the increase in seismicity neglect to include considerations for effects of small magnitude cluster events on federal infrastructure. These effects can be almost undetectable at first, but if left unchecked can evolve into a larger issue. The need to reassess and potentially modify the established risk assessment practices for evaluations of federal infrastructure needs to be reviewed to ensure the continued ability of the structure to function as intended. The U.S. Army Corps of Engineers (USACE) is responsible for hydroelectric power, flood protection, recreational areas, navigational channels and water supply along …


Thermodynamic Characterization Of Free And Surface Water Of Colloidal Unimolecular Polymer (Cup) Particles Utilizing Dsc, Peng Geng, Ashish Zore, Michael R. Van De Mark Jun 2020

Thermodynamic Characterization Of Free And Surface Water Of Colloidal Unimolecular Polymer (Cup) Particles Utilizing Dsc, Peng Geng, Ashish Zore, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

Colloidal Unimolecular Polymer (CUP) particles are spheroidal, 3-9 nm with charged groups on the surface and a hydrophobic core, which offer a larger surface water fraction to improve the analysis of its characteristics. Differential scanning calorimetry (DSC) was performed to determine the characteristics of surface water. These properties include the amount of surface water, the layer thickness, density, specific heat of the surface water above and below the freezing point of water, melting point depression of free water, effect of charge density and particle size. The charge density on the CUP surface was varied as well as the molecular weight …


Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher Jun 2020

Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Explore The Stability Of The Phase Separation Phenomenon In Few-Fermion Spin-1/2 Systems Confined In A Double-Well Potential. It Is Shown That Within The SU(2) Symmetric Case, Where The Total Spin Is Conserved, The Phase Separation Cannot Be Fully Stabilized. An Interaction Regime Characterized By Metastable Phase Separation Emerges For Intermediate Interactions Which Is Inherently Related With Ferromagnetic Spin-Spin Correlations Emerging Within Each Of The Wells. The Breaking Of The SU(2) Symmetry Crucially Affects The Stability Properties Of The System As The Phase Separated State Can Be Stabilized Even For Weak Magnetic Potential Gradients. Our Results Imply An Intricate Relation …


Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha Jun 2020

Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha

Materials Science and Engineering Faculty Research & Creative Works

Froth flotation process is extensively used for selective separation of base metal sulfides from uneconomic mineral resources. Reliable prediction of process outcomes (metal recovery and grade) is vital to ensure peak performance. This work employs an innovative hybrid machine learning (ML) model—constructed by combining the random forest model and the firefly algorithm—to predict froth flotation efficiency of galena and chalcopyrite in relation to various experimental process parameters. The hybrid model's prediction performance was rigorously evaluated and compared against four different standalone ML models. The outcomes of this study illustrate that the hybrid ML model has the prediction ability to process …


Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura Jun 2020

Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Two recent experimental observations at the ATOMKI Institute of the Hungarian Academy of Sciences (regarding the angular emission pattern of electron-positron pairs from nuclear transitions from excited states in 8Be and 4He) indicate the possible existence of a particle of a rest mass energy of roughly 17 MeV. The so-called X17 particle constitutes a virtual state in the process, preceding the emission of the electron-positron pair. Based on the symmetry of the nuclear transitions (1+ → 0+ and 0- →0 +), the X17 could either be a vector, or a pseudoscalar particle. Here, we …


Deep Minima In The Triply Differential Cross Section For Ionization Of Atomic Hydrogen By Electron And Positron Impact, C. M. Demars, S. J. Ward, J. Colgan, S. Amami, Don H. Madison Jun 2020

Deep Minima In The Triply Differential Cross Section For Ionization Of Atomic Hydrogen By Electron And Positron Impact, C. M. Demars, S. J. Ward, J. Colgan, S. Amami, Don H. Madison

Physics Faculty Research & Creative Works

We investigate ionization of atomic hydrogen by electron-and positron-impact. We apply the Coulomb-Born (CB1) approximation, various modified CB1 approximations, the three-body distorted wave (3DW) approximation, and the time-dependent close-coupling (TDCC) method to electron-impact ionization of hydrogen. For electron-impact ionization of hydrogen for an incident energy of approximately 76.45 eV, we obtain a deep minimum in the CB1 triply differential cross section (TDCS). However, the TDCC for 74.45 eV and the 3DW for 74.46 eV gave a dip in the TDCS. For positron-hydrogen ionization (breakup) we apply the CB1 approximation and a modified CB1 approximation. We obtain a deep minimum in …


Dc Ir-Drop Analysis Of Multilayered Power Distribution Network By Discontinuous Galerkin Method With Thermal Effects Incorporated, Ping Li, Min Tang, Zhi Xiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci Jun 2020

Dc Ir-Drop Analysis Of Multilayered Power Distribution Network By Discontinuous Galerkin Method With Thermal Effects Incorporated, Ping Li, Min Tang, Zhi Xiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the temperature-dependent resistivity of power distribution network (PDN) interconnects, a wiser and necessary strategy is to proceed the electrical-thermal cosimulation in order to include the thermal effects caused by Joule heating. As a natural domain decomposition method (DDM), in this article, a discontinuous Galerkin (DG) method is proposed to facilitate the steady-state electrical and thermal coanalysis. With the intention to avoid solving a globally coupled steady-state matrix system equations resulted from the implicit numerical flux in DG, the block Thomas method is deployed to solve the entire domain in a subdomain-by-subdomain scheme. As a direct solver, the block …