Results 161 to 170 of about 7,955 (262)

New views of some invariants associated with the Cartesian 2D velocity gradient tensor

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Vorticity and divergence of horizontal flow are fundamental quantities in meteorology; both are linear functions of the four elements of the 2D velocity gradient tensor and both are formally unchanged under coordinate rotation. We explore four quadratic functions of the elements that are geometrically invariant in this sense, finding some novel ...
I. Roulstone, S. A. Clough, A. A. White
wiley   +1 more source

Generalization of Bandlimited Functions and Applications to Quantum Probability Distributions. [PDF]

Entropy (Basel)
Cohen L.
europepmc   +1 more source

Propagation of internal gravity waves: Optimal vertical discretisation and grid design based on numerical error analysis

Quarterly Journal of the Royal Meteorological Society, EarlyView.
An energy‐conserving discrete framework for the vertical discretisation of stratified ocean models is developed using internal gravity‐wave theory. A β$$ \beta $$‐indexed family of schemes is analysed through perturbation theory, revealing optimal parameter choices and grid designs that reduce truncation errors significantly.
Gabriel Derrida, Laurent Debreu, Florian Lemarié, Jérome Chanut   +3 more
wiley   +1 more source

Spectral Insights into Active Matter: Exceptional Points and the Mathieu Equation. [PDF]

Entropy (Basel)
Boltz HH, Ihle T.
europepmc   +1 more source

ZenBand: a numerical solver of photonic crystals with a graphical user interface. [PDF]

Sci Rep
Zinkevičius A, Lukošiūnas I, Gailevičius D.   +2 more
europepmc   +1 more source

Self-supervised reservoir computing with spatial-temporal encoding for identifying critical transitions. [PDF]

Nat Commun
Yang N, Kurths J, Liu R, Chen P.
europepmc   +1 more source

Optimal Homogeneous ℒp$$ {\boldsymbol{\mathcal{L}}}_{\boldsymbol{p}} $$‐Gain Controller

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT Nonlinear ℋ∞$$ {\mathscr{H}}_{\infty } $$‐controllers are designed for arbitrarily weighted, continuous homogeneous systems with a focus on systems affine in the control input. Based on the homogeneous ℒp$$ {\mathcal{L}}_p $$‐norm, the input–output behavior is quantified in terms of the homogeneous ℒp$$ {\mathcal{L}}_p $$‐gain as a ...
Daipeng Zhang, Benjamin Calmbach, Jaime A. Moreno, Johann Reger   +3 more
wiley   +1 more source

Eigenbased Multi-Antenna Spectrum Sensing: Experimental Validation on a Software-Defined Radio Testbed. [PDF]

Sensors (Basel)
Riviello DG, Alfano G.
europepmc   +1 more source

Control Design Based on Generalized Lur'e Lyapunov Functions for Sampled‐Data Lur'e Systems

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT This article addresses the synthesis of stabilizing control laws for aperiodic sampled‐data Lur'e systems. Based on a hybrid system representation of the closed‐loop system and a timer‐dependent generalized Lur'e–Postnikov type Lyapunov function, stabilization conditions are obtained by separating decision variables with the application of two
Arthur Scolari Fagundes, João Manoel Gomes da Silva Jr., Sophie Tarbouriech   +2 more
wiley   +1 more source

A Novel, Variance Component-Based Method for Detecting Brain-Behavior Associations in Neuroimaging Data. [PDF]

Stat Data Sci Imaging
Chen C, Rubin J, Rennert L, Edmondson M, Vandekar SN, Shinohara RT.   +5 more
europepmc   +1 more source