Results 21 to 30 of about 144,037 (209)

On Fourier integral operators with Hölder-continuous phase [PDF]

Analysis and Applications, 2018
We study continuity properties in Lebesgue spaces for a class of Fourier integral operators arising in the study of the Boltzmann equation. The phase has a Hölder-type singularity at the origin. We prove boundedness in [Formula: see text] with a precise loss of decay depending on the Hölder exponent, and we show by counterexamples that a loss occurs ...
Cordero, Elena, Nicola, Fabio, Primo, Eva   +2 more
openaire   +6 more sources

Microlocal Analysis of Some Isospectral Deformations [PDF]

, 1994
We study the microlocal structure of the examples of isospectral deformations of Riemannian manifolds given by D. DeTurck and C. Gordon in [DeT-G1]. The Schwartz kernel of the intertwining operators considered by them may be written as an oscillatory ...
Marhuenda, Francisco
core   +3 more sources

Approximation of Fourier Integral Operators by Gabor Multipliers [PDF]

Journal of Fourier Analysis and Applications, 2012
22 ...
CORDERO, Elena, K. Groechenig, F. Nicola
openaire   +5 more sources

Bicharacteristics and Fourier integral operators in Kasner spacetime [PDF]

International Journal of Geometric Methods in Modern Physics, 2015
The scalar wave equation in Kasner spacetime is solved, first for a particular choice of Kasner parameters, by relating the integrand in the wave packet to the Bessel functions. An alternative integral representation is also displayed, which relies upon the method of integration in the complex domain for the solution of hyperbolic equations with ...
ESPOSITO G, BATTISTA E, DI GREZIA E
openaire   +4 more sources

Oscillatory and Fourier Integral operators with degenerate canonical relations [PDF]

, 2002
We mostly survey results concerning the $L^2$ boundedness of oscillatory and Fourier integral operators. This article does not intend to give a broad overview; it mainly focusses on a few topics directly related to the work of the authors.Comment: 37 ...
Greenleaf, Allan, Seeger, Andreas
core   +5 more sources

Multi‐institutional study on image quality for a novel CBCT solution on O‐ring linac

Journal of Applied Clinical Medical Physics, EarlyView.
Abstract Introduction This work presents a multi‐institutional study on image quality provided by a novel cone beam computed tomography (CBCT). The main goal is to investigate the consistency of imaging performance across multiple institutions.
Luis Agulles‐Pedrós, R. Lee MacDonald, Amanda Jean Cherpak, Nayha Dixit, Lei Dong, Tianyu Zhao, Kundan Thind, Anthony Doemer, Boon‐Keng Teo, Shiqin Su, Alexander Moncion, James L. Robar   +11 more
wiley   +1 more source

$L^p$-boundedness and $L^p$-nuclearity of multilinear pseudo-differential operators on $\mathbb{Z}^n$ and the torus $\mathbb{T}^n$

, 2019
In this article, we begin a systematic study of the boundedness and the nuclearity properties of multilinear periodic pseudo-differential operators and multilinear discrete pseudo-differential operators on $L^p$-spaces. First, we prove analogues of known
Cardona, Duván, Kumar, Vishvesh
core   +2 more sources

Mechanisms of Increasing Weld Depth during Temporal Power Modulation in High‐Power Laser Beam Welding

Advanced Engineering Materials, EarlyView.
Temporal power modulation increases weld depth in high‐power laser beam welding of dissimilar round bars by nearly 20% compared to same average continuously welded welding power. The mechanism of action also applies to sheet welding and depends on the inertia of keyhole depth for the modulated laser beam power.
Jan Grajczak, David Reynders, Christian Nowroth, Jens Twiefel, Jörg Wallaschek, Sarah Nothdurft, Jörg Hermsdorf, Stefan Kaierle   +7 more
wiley   +1 more source

A Different Perspective on the Solid Lubrication Performance of Black Phosphorous: Friend or Foe?

Advanced Engineering Materials, EarlyView.
Researchers investigate black phosphorous (BP) as a standalone solid lubricant coating through ball‐on‐disc linear‐reciprocating sliding experiments in dry conditions. Testing on different metals shows BP doesn't universally reduce friction and wear. However, it achieves 33% friction reduction on rougher iron surfaces and 23% wear reduction on aluminum.
Matteo Vezzelli, Manel Rodríguez Ripoll, Sabine Schwarz, Ali Erdemir, Maria Clelia Righi, Carsten Gachot   +5 more
wiley   +1 more source

A Class of Fourier Integral Operators on Manifolds with Boundary [PDF]

, 2015
We study a class of Fourier integral operators on compact manifolds with boundary, associated with a natural class of symplectomorphisms, namely, those which preserve the boundary. A calculus of Boutet de Monvel's type can be defined for such Fourier integral operators, and appropriate continuity properties established.
BATTISTI, UBERTINO, CORIASCO, Sandro, E. Schrohe   +2 more
openaire   +4 more sources