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Displaying 26 - 50 of 466

Spatially-Dependent Model for Rods and Cones in the Retina

December 14, 2023
Author(s)
Daniel M. Anderson, Danielle Brager, Anthony J. Kearsley
We develop a mathematical model for photoreceptors in the retina. We focus on rod and cone outer segment dynamics and interactions with a nutrient source associated with the retinal pigment epithelium cells. Rod and cone densities (number per unit area of

Automated interpretation of firearm mark comparison results

December 13, 2023
Author(s)
Martin Baiker-Sorensen, Ivo Alberink, Laura Granell, Leen van der Ham, Erwin J.A.T. Mattijssen, Erich Smith, Johannes A. Soons, Peter Vergeer, Xiaoyu Alan Zheng
In this article an automated approach for interpretation of firearm mark comparison results is presented. First, similarity scores are derived for marks typically encountered on primers of fired cartridge cases: aperture shear striations as well as

Monitoring Spectrometer Drift with Unsupervised Machine Learning

November 20, 2023
Author(s)
Benjamin Harding, Ziling Hu, Ashley Hiett, Frank Delaglio, Katherine Henzler- Wildman, Chad Rienstra
Solid-state NMR spectroscopy (SSNMR) is a powerful technique to probe structural and dynamic properties of molecules at an atomic level. Modern SSNMR methods employ multidimensional pulse sequences requiring data collection over a period of days to weeks

Partial Elastic Shape Registration of 3D Surfaces using Dynamic Programming

November 3, 2023
Author(s)
Javier Bernal, James F. Lawrence
The computation of the elastic shape registration of two simple surfaces in 3−dimensional space and therefore of the elastic shape distance between them has been investigated by Kurtek, Jermyn, et al. who have proposed algorithms to carry out this

Multi-integral representations for Jacobi functions of the first and second kind

October 5, 2023
Author(s)
Howard Cohl, Roberto S. Costas-Santos
One may consider the generalization of Jacobi polynomials and the Jacobi func- tion of the second kind to a general function where the index is allowed to be a complex number instead of a non-negative integer. These functions are referred to as Jacobi func

Maximally Edge-Connected Realizations and Kundu's k-factor Theorem

August 3, 2023
Author(s)
James Shook
A simple graph $G$ with edge-connectivity $\lambda(G)$ and minimum degree $\delta(G)$ is maximally edge connected if $\lambda(G)=\delta(G)$. In 1964, given a non-increasing degree sequence $\pi=(d_1},\ldots,d_n})$, Jack Edmonds showed that there is a

Discovery and Recognition of Formula Concepts Using Machine Learning

July 13, 2023
Author(s)
Howard Cohl, Bela Gipp, Moritz Schubotz, Philipp Scharpf
Citation-based Information Retrieval (IR) methods for scientific documents have proven effective for IR applications, such as Plagiarism Detection or Literature Recommender Systems in academic disciplines that use many references. In science, technology

Status Report on the Final Round of the NIST Lightweight Cryptography Standardization Process

June 16, 2023
Author(s)
Meltem Sonmez Turan, Kerry McKay, Donghoon Chang, Jinkeon Kang, Noah Waller, John M. Kelsey, Lawrence E. Bassham, Deukjo Hong
The National Institute of Standards and Technology (NIST) initiated a public standardization process to select one or more Authenticated Encryption with Associated Data (AEAD) and hashing schemes suitable for constrained environments. In February 2019, 57

Noise-resilient deep tomographic imaging

April 24, 2023
Author(s)
Zhen Guo, Zhiguang Liu, George Barbastathis, Qihang Zhang, Michael Glinsky, Bradley Alpert, Zachary H. Levine
X-ray tomography is a non-destructive imaging technique that reveals the interior of an object from its projections at different angles. Under limited-angle and low-photon sampling, a regularization prior is required to retrieve a high-fidelity

Separable Shape Tensors for Aerodynamic Design

January 31, 2023
Author(s)
Zachary J. Grey, Andrew Glaws, Olga Doronina
Airfoil shape design is a classical problem in engineering and manufacturing. In this work, we combine principled physics-based considerations for the shape design problem with modern computational techniques using a data-driven approach. Modern and

Restricted Domain Compressive Sensing for Antenna Metrology

November 21, 2022
Author(s)
Marc Valdez, Alex Yuffa, Michael Wakin
In this paper, we prove a compressive sensing guarantee for restricted measurement domains in spherical near-field to far-field transformations for antenna metrology. We achieve this by first defining Slepian functions on a measurement sub-domain $R$ of

Extracting Mathematical Concepts from Text

October 12, 2022
Author(s)
Jacob Collard, Valeria de Paiva, Brendan Fong, Eswaran Subrahmanian
We investigate some different systems for extracting mathematical entities from texts in the mathematical field of category theory, as a first step for constructing a mathematical knowledge graph. We consider four different term extractors and compare

A characterization of the Centers of Chordal Graphs

September 30, 2022
Author(s)
James Shook, Bing Wei
A graph is $k$-chordal if it does not have an induced cycle with length greater than $k$. We call a graph chordal if it is $3$-chordal. Let $G$ be a graph. The distance between the vertices $x$ and $y$, denoted by $d_G}(x,y)$, is the length of a shortest
Displaying 26 - 50 of 466