Search
Now showing items 251-259 of 259
An efficient image encryption scheme based on fractal Tromino and Chebyshev polynomial
(
Springer International Publishing
, 2021 , Article)
The security of digital content during transmission and storage through insecure communication links and databases is a challenging issue in today's world. In this article, an encryption scheme based on fractal Tromino and ...
Polycircular domains, numerical conformal mappings, and moduli of quadrilaterals
(
Springer Nature
, 2022 , Article)
We study numerical conformal mappings of planar Jordan domains with boundaries consisting of finitely many circular arcs, also called polycircular domains, and compute the moduli of quadrilaterals for these domains. ...
Finding the Nearest Negative Imaginary System with Application to Near-Optimal Controller Design
(
Institute of Electrical and Electronics Engineers Inc.
, 2023 , Conference Paper)
In this paper, we consider the problem of robust stabilization of linear time-invariant systems with respect to unmodeled dynamics and structure uncertainties. To that end, we first present a methodology to find the nearest ...
Turning point in COVID-19 severity and fatality during the pandemic: a national cohort study in Qatar
(
BMJ Publishing Group
, 2023 , Article)
Objective To assess the evolution of COVID-19 severity and fatality in a unique setting that consistently applied, throughout the pandemic, rigorous and standardised criteria for defining severe COVID-19 outcomes.
Methods ...
Robust stabilization of LTI negative imaginary systems using the nearest negative imaginary controller
(
John Wiley and Sons Inc
, 2023 , Article)
This paper considers the problem of robust stabilization of linear time-invariant systems with respect to unmodelled dynamics and structure uncertainties. To that end, a methodology to find the nearest negative imaginary ...
History of primary-series and booster vaccination and protection against Omicron reinfection
(
American Association for the Advancement of Science
, 2023 , Article)
Laboratory evidence suggests a possibility of immune imprinting for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the differences in the incidence of SARS-CoV-2 reinfection in a ...
Estimating protection afforded by prior infection in preventing reinfection: Applying the test-negative study design.
(
Oxford University Press
, 2023 , Article)
The COVID-19 pandemic has highlighted the need to use infection testing databases to rapidly estimate effectiveness of prior infection in preventing reinfection ($P{E}_S$) by novel SARS-CoV-2 variants. Mathematical modeling ...
Instability of Langmuir-beam waves: Kappa-distributed electrons
(
American Institute of Physics Inc.
, 2023 , Article)
In space plasmas, electron populations exhibit non-equilibrium velocity distributions with high-energy tails that are reproduced by the Kappa power-laws and contrast with the Maxwellian distributions often used in theoretical ...
Kappa-Distributed Electrons in Solar Outflows: Beam-Plasma Instabilities and Radio Emissions
(
Springer Science and Business Media B.V.
, 2023 , Article)
Electrostatic (ES) wave instabilities are assumed to be at the origin of radio emissions from interplanetary shocks, and solar coronal sources are most likely induced by electron beams, more energetic but less dense than ...