Publications associées à Fonction quadratique

Hierarchy of quasisymmetries and degeneracies in the CoSi family of chiral crystal materials

Philip Johannes Walter Moll, Chunyu Guo, Yi-Chiang Sun

In materials, certain approximated symmetry operations can exist in a lower-order approximation of the effective model but are good enough to influence the physical responses of the system, and these approximated symmetries were recently dubbed "quasisymme ...

AMER PHYSICAL SOC2023

Simulating supercontinua from mixed and cascaded nonlinearities

Luis Guillermo Villanueva Torrijo, Victor Brasch, Furkan Ayhan, Tobias Herr, Thibault Voumard

Nonlinear optical frequency conversion is of fundamental importance in photonics and underpins countless of its applications: Sum- and difference-frequency generation in media with quadratic nonlinearity permits reaching otherwise inaccessible wavelength r ...

AIP Publishing2023

Byzantine consensus is Θ(n^2): the Dolev-Reischuk bound is tight even in partial synchrony!

Rachid Guerraoui, Jovan Komatovic, Manuel José Ribeiro Vidigueira, Pierre Philippe Civit, Vincent Gramoli, Seth Gilbert

The Dolev-Reischuk bound says that any deterministic Byzantine consensus protocol has (at least) quadratic (in the number of processes) communication complexity in the worst case: given a system with n processes and at most f < n/3 failures, any solution t ...

2023

Strictly Real Fundamental Theorem Of Algebra Using Polynomial Interlacing

Soham Basu

Without resorting to complex numbers or any advanced topological arguments, we show that any real polynomial of degree greater than two always has a real quadratic polynomial factor, which is equivalent to the fundamental theorem of algebra. The proof uses ...

CAMBRIDGE UNIV PRESS2021

TV-based reconstruction of periodic functions

Matthieu Martin Jean-André Simeoni, Julien René Pierre Fageot

We introduce a general framework for the reconstruction of periodic multivariate functions from finitely many and possibly noisy linear measurements. The reconstruction task is formulated as a penalized convex optimization problem, taking the form of a sum ...

IOP PUBLISHING LTD2020

Apparent diffusion coefficient measured by diffusion MRI of moving and deforming domains

Jan Sickmann Hesthaven

The modeling of the diffusion MRI signal from moving and deforming organs such as the heart is challenging due to significant motion and deformation of the imaged medium during the signal acquisition. Recently, a mathematical formulation of the Bloch-Torre ...

Academic Press Inc - Elsevier Science2020

Mapping Electrochemical Heterogeneity at Gold Surfaces: A Second Harmonic Imaging Study

Sylvie Roke, Arianna Marchioro, Igor Nahálka

Designing efficient catalysts requires correlating surface structure and local chemical composition with reactivity on length scales from nanometers to tens of microns. While much work has been done on this structure/function correlation on single crystals ...

2020

Charge fluctuations from molecular simulations in the constant-potential ensemble

Sara Bonella, Alessandro Coretti

We revisit the statistical mechanics of charge fluctuations in capacitors. In constant-potential classical molecular simulations, the atomic charges of electrode atoms are treated as additional degrees of freedom which evolve in time so as to satisfy the c ...

2020

Four-Variable Expanders Over The Prime Fields

Adrian Claudiu Valculescu, Van Thang Pham, Seyed Hossein Nassajianmojarrad

Let F-p be a prime field of order p > 2, and let A be a set in F-p with very small size in terms of p. In this note, we show that the number of distinct cubic distances determined by points in A x A satisfies vertical bar(A - A)(3) + (A - A)(3 vertical bar ...

AMER MATHEMATICAL SOC2018

Two-step phase demodulation algorithm based on quadratic phase parameter estimation using state space analysis

Pramod Rastogi, Rishikesh Dilip Kulkarni

We propose a noise robust two-step phase shifting algorithm for the evaluation of random and unknown phase step. In this algorithm, the phase within a small size two-dimensional window around a user selected pixel in an interferogram is approximated as a q ...

2018