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One-Dimensional Sensor Learns To Sense Three-Dimensional Space, Chen Zhu, Rex E. Gerald, Yizheng Chen, Jie Huang Jun 2020

One-Dimensional Sensor Learns To Sense Three-Dimensional Space, Chen Zhu, Rex E. Gerald, Yizheng Chen, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

A sensor system with ultra-high sensitivity, high resolution, rapid response time, and a high signal-to-noise ratio can produce raw data that is exceedingly rich in information, including signals that have the appearances of "noise". The "noise"feature directly correlates to measurands in orthogonal dimensions, and are simply manifestations of the off-diagonal elements of 2nd-order tensors that describe the spatial anisotropy of matter in physical structures and spaces. The use of machine learning techniques to extract useful meanings from the rich information afforded by ultra-sensitive one-dimensional sensors may offer the potential for probing mundane events for novel embedded phenomena. Inspired by our …

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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.

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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 …

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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.

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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 …

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Channel Estimators For Full-Duplex Communication Using Orthogonal Pilot Sequences, Arul Mathi Maran Chandran, Lei Wang, Maciej Jan Zawodniok Jun 2020

Channel Estimators For Full-Duplex Communication Using Orthogonal Pilot Sequences, Arul Mathi Maran Chandran, Lei Wang, Maciej Jan Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Full-duplex communication is desirable to maximize the spectral efficiency, despite the challenges it puts forth. The key challenge inhibiting the operation of radios in full-duplex mode is self-interference. In this paper, we propose a pilot-based channel estimation to estimate both self-interference and communication channels simultaneously at both ends of a full-duplex link using orthogonal sequences. The Cramer-Rao Lower Bound for estimators of both the channels was determined and compared with the half-duplex channel estimator. We performed simulations varying sequence length and channel taps and studied the performance of the estimators. We also studied the effect of synchronization between the sequences …

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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 …

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Resistive Switching In Atomic Layer Deposited Hfo2/Zro2 Nanolayer Stacks, Lin Tang, Hiraku Maruyama, Taihao Han, Juan C. Nino, Yonghong Chen, Dou Zhang Jun 2020

Resistive Switching In Atomic Layer Deposited Hfo2/Zro2 Nanolayer Stacks, Lin Tang, Hiraku Maruyama, Taihao Han, Juan C. Nino, Yonghong Chen, Dou Zhang

Materials Science and Engineering Faculty Research & Creative Works

The resistive switching properties of HfO2/ZrO2 nanolayers with the total thickness of 16 nm prepared using atomic layer deposition (ALD) were investigated. Current-voltage behavior, pulse time mode measurement, retention and endurance tests were carried out to characterize the memristive (memory-resistive) properties. Resistive switching was observed in all nanolayer stacks, and the set voltage (Vset) decreased with increasing the number of layers (i.e., increasing number of hafnia-zirconia interfaces). Grazing incidence x-ray diffraction (GI-XRD) results demonstrate that the hafnia transforms from monoclinic to orthorhombic crystal structure during the post metallization annealing. Shifts in the binding energy of the x-ray …

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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 …

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Faculty Senate Meeting Minutes Jun 11, 2020, Missouri University Of Science And Technology Faculty Senate Jun 2020

Faculty Senate Meeting Minutes Jun 11, 2020, Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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, …

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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.

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Missouri S&T Magazine Summer 2020, Missouri S&T Marketing And Communications Department, Miner Alumni Association Jun 2020

Missouri S&T Magazine Summer 2020, Missouri S&T Marketing And Communications Department, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

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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.

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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 …

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Spectroscopic Measurements Of Dissolved O3, H2o2 And Oh Radicals In Double Cylindrical Dielectric Barrier Discharge Technology: Treatment Of Methylene Blue Dye Simulated Wastewater, Emile Salomon Massima Mouele, Jimoh O. Tijani, Milua Masikini, Ojo O. Fatoba, Chuks P. Eze, Chionydua T. Onwordi, Myo Tay Zar Myint, Htet Htet Kyaw, Jamal Al-Sabahi, Mohammed Al-Abri, Sergey Dobretsov, Katri Laatikainen, Leslie F. Petrik Jun 2020

Spectroscopic Measurements Of Dissolved O3, H2o2 And Oh Radicals In Double Cylindrical Dielectric Barrier Discharge Technology: Treatment Of Methylene Blue Dye Simulated Wastewater, Emile Salomon Massima Mouele, Jimoh O. Tijani, Milua Masikini, Ojo O. Fatoba, Chuks P. Eze, Chionydua T. Onwordi, Myo Tay Zar Myint, Htet Htet Kyaw, Jamal Al-Sabahi, Mohammed Al-Abri, Sergey Dobretsov, Katri Laatikainen, Leslie F. Petrik

Mining Engineering Faculty Research & Creative Works

Advanced oxidation technologies (AOTs) focusing on nonthermal plasma induced by dielectric barrier discharge are adequate sources of diverse reactive oxygen species (ROS) beneficial for water and wastewater treatment. In this study, indigo, peroxytitanyl sulphate and terephthalic acid methods were used to approximate the concentrations of O3, H2O2 and OH produced in a double cylindrical dielectric barrier discharge (DCDBD) plasma configuration. The effect of pH and scavengers as well as the amount of chemical probes on the generation of oxidants was investigated. The efficiency of the DCDBD reactor was further evaluated using methylene blue (MB) as …

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Spectrum Analyzer-Based Phase Measurement For Near-Field Emi Scanning, Shubhankar Marathe, Zongyi Chen, Kaustav Ghosh, Hamed Kajbaf, Stephan Frei, Morten Sorensen, David Pommerenke, Jin Min Jun 2020

Spectrum Analyzer-Based Phase Measurement For Near-Field Emi Scanning, Shubhankar Marathe, Zongyi Chen, Kaustav Ghosh, Hamed Kajbaf, Stephan Frei, Morten Sorensen, David Pommerenke, Jin Min

Electrical and Computer Engineering Faculty Research & Creative Works

Often, electromagnetic interference (EMI) scanning applications require phase and magnitude information for the creation of equivalent radiation models and far-field predictions. Magnitude information can be obtained using a spectrum analyzer (SA), which is relatively inexpensive compared to phase resolving instruments such as vector network analyzers (VNAs) and oscilloscopes at tens of GHz. This paper introduces and optimizes a cost-effective SA-based phase measurement method and compares the results to a VNA and oscilloscope-based methods for EMI signal sources. The measured-phase distribution obtained from the three different instruments is additionally compared with the simulated phase determined from full-wave simulation. The three measurement …

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A Review Of The Latest Insights Into The Mechanism Of Action Of Strontium In Bone, Daniella Marx, Alireza Rahimnejad Yazdi, Marcello Papini, Mark R. Towler Jun 2020

A Review Of The Latest Insights Into The Mechanism Of Action Of Strontium In Bone, Daniella Marx, Alireza Rahimnejad Yazdi, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Interest in strontium (Sr) has persisted over the last three decades due to its unique mechanism of action: it simultaneously promotes osteoblast function and inhibits osteoclast function. While this mechanism of action is strongly supported by in vitro studies and small animal trials, recent large-scale clinical trials have demonstrated that orally administered strontium ranelate (SrRan) may have no anabolic effect on bone formation in humans. Yet, there is a strong correlation between Sr accumulation in bone and reduced fracture risk in post-menopausal women, suggesting Sr acts via a purely physiochemical mechanism to enhance bone strength. Conversely, the local administration of …

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The Role Of Poly(Methyl Methacrylate) In Management Of Bone Loss And Infection In Revision Total Knee Arthroplasty: A Review, Leyla Hasandoost, Omar Rodriguez, Adel Alhalawani, Paul Zalzal, Emil H. Schemitsch, Stephen D. Waldman, Marcello Papini, Mark R. Towler Jun 2020

The Role Of Poly(Methyl Methacrylate) In Management Of Bone Loss And Infection In Revision Total Knee Arthroplasty: A Review, Leyla Hasandoost, Omar Rodriguez, Adel Alhalawani, Paul Zalzal, Emil H. Schemitsch, Stephen D. Waldman, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Poly (methyl methacrylate) (PMMA) is widely used in joint arthroplasty to secure an implant to the host bone. Complications including fracture, bone loss and infection might cause failure of total knee arthroplasty (TKA), resulting in the need for revision total knee arthroplasty (rTKA). The goals of this paper are: (1) to identify the most common complications, outside of sepsis, arising from the application of PMMA following rTKA, (2) to discuss the current applications and drawbacks of employing PMMA in managing bone loss, (3) to review the role of PMMA in addressing bone infection following complications in rTKA. Papers published between …

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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 …

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Impulse And Performance Measurements Of Electric Solid Propellant In A Laboratory Electrothermal Ablation-Fed Pulsed Plasma Thruster, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin Jun 2020

Impulse And Performance Measurements Of Electric Solid Propellant In A Laboratory Electrothermal Ablation-Fed Pulsed Plasma Thruster, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled and extinguished) through the application and removal of an electric current. This behavior may enable the propellant to be used in multimode propulsion systems utilizing the ablative pulsed plasma thruster. The performance of an electric solid propellant operating in an electrothermal ablation-fed pulsed plasma thruster was investigated using an inverted pendulum micro-newton thrust stand. The impulse bit and specific impulse of the device using the electric solid propellant were measured for short-duration test runs of 100 pulses and longer-duration runs to end-of-life, at energy levels …

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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 …

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