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Displaying 26 - 50 of 507

Internal and external harmonics in bi-cyclide coordinates

July 20, 2023
Author(s)
Hans Volkmer, Brandon Alexander, Howard Cohl
The Laplace equation in three-dimensional Euclidean space is R-separable in bi-cyclide coordinates leading to harmonic functions expressed in terms of Lamé–Wangerin functions called internal and external bi-cyclide harmonics. An expansion for a fundamental

O-RAN with Machine Learning in ns-3

June 28, 2023
Author(s)
Wesley Garey, Richard A. Rouil, Evan Black, Tanguy Ropitault, Weichao Gao
The Open Radio Access Network (O-RAN) Alliance is the industry led standardization effort, with the sole purpose of evolving the Radio Access Network (RAN) to be more open, intelligent, interoperable, and autonomous to support the ever growing need of

pH response of sequence-controlled polyampholyte brushes

May 31, 2023
Author(s)
Xin Yuan, Harold Hatch, Jacinta Conrad, Amanda Marciel, Jeremy Palmer
We use molecular simulation to investigate the pH response of sequence-controlled polyampholyte brushes (PABs) with polymer chains consisting of alternating blocks of weakly acidic and basic monomers. Changes in the ionization state, height, lateral

Model Validation for Scanning Electron Microscopy

April 27, 2023
Author(s)
Olga Ridzel, Wataru Yamane, Ishiaka Mansaray, John S. Villarrubia
We are beginning projects to validate the physics models used for interpretation of electron microscopy images. In one, we will measure electron yields and energy spectra from cleaned well-characterized samples subjected to electron bombardment inside of a

Investigating the Harmonic Dependence of MPI Resolution

March 19, 2023
Author(s)
Mark-Alexander Henn, Thinh Bui, Solomon I. Woods
In this work we investigate how the MPI resolution changes as a function of signal harmonics. Based on a simulation study that models a lock-in measurement of the point spread function we apply our findings to actual measurement data obtained from NIST's

Investigating the Influence of Sampling Frequency on X-Space MPI Image Reconstructions

March 19, 2023
Author(s)
Mark-Alexander Henn, Klaus Natorf Quelhas, Solomon I. Woods
In this presentation we employ a direct X-space deconvolution to estimate particle distributions from MPI data. We report on how the accuracy of those estimations changes as a function of sampling frequency and compare the findings to the MPI core operator

AtomVision: A machine vision library for atomistic images

March 1, 2023
Author(s)
Brian DeCost, Ramya Gurunathan, Adam Biacchi, Kamal Choudhary
Computer vision techniques have immense potential for materials design applications. In this work, we introduce an integrated and general-purpose AtomVision library that can be used to generate and curate microscopy image (such as scanning tunneling

Category Theory

January 25, 2023
Author(s)
Spencer Breiner, Eswaran Subrahmanian, Ram Sriram
Category theory (CT) is a branch of mathematics concerned with the representation and composition of structured relationships. Recent interest in systems engineering (SE) stems from the possibility that CT might provide a principled mathematical foundation

Encouraging and Enabling Mutual Ownership in a RSE Community of Practice

November 21, 2022
Author(s)
Miranda Mundt, Jonathan Bisila, Jonathan E. Guyer, Daniel Howard, Daniel S. Katz, Reed Milewicz, Henry Schreiner, Joshua Teves, Chris Wiswell
The explosion of Research Software Engineers (RSEs) in the United States created the opportunity to form communities of practice (CoP), groups which share a passion for an activity and learn how to do it better as they interact regularly, specifically to

On-grid compressive sampling for spherical field measurements in acoustics

October 18, 2022
Author(s)
Alex Yuffa, Marc Valdez, Michael Wakin
We derive a theoretically guaranteed compressive sensing method for acoustic field reconstructions using spherical field measurements on a predefined grid. This method can be used to reconstruct sparse band-limited spherical harmonic or Wigner $D$-function
Displaying 26 - 50 of 507