Results 11 to 20 of about 1,696,719 (268)

Fourier phase analysis in radio-interferometry [PDF]

, 2006
Most statistical tools used to characterize the complex structures of the interstellar medium can be related to the power spectrum, and therefore to the Fourier amplitudes of the observed fields.
Falgarone, Edith, Levrier, Francois, Viallefond, Francois   +2 more
core   +4 more sources

Operator-valued zeta functions and Fourier analysis [PDF]

, 2019
The Riemann zeta function $\zeta(s)$ is defined as the infinite sum $\sum_{n=1}^\infty n^{-s}$, which converges when ${\rm Re}\,s>1$. The Riemann hypothesis asserts that the nontrivial zeros of $\zeta(s)$ lie on the line ${\rm Re}\,s= \frac{1}{2}$. Thus,
Bender, Carl M., Brody, Dorje C
core   +2 more sources

The Clifford-Fourier integral kernel in even dimensional Euclidean space [PDF]

, 2010
Recently, we devised a promising new multi-dimensional integral transform within the Clifford analysis setting, the so-called Fourier–Bessel transform.
Brackx, Fred, De Schepper, Nele, Sommen, Franciscus   +2 more
core   +1 more source

Parametric Resonance in Neutrino Oscillation: A Guide to Control the Effects of Inhomogeneous Matter Density [PDF]

, 2016
Effects of the inhomogeneous matter density on the three-generation neutrino oscillation probability are analyzed. Realistic profile of the matter density is expanded into a Fourier series. Taking in the Fourier modes one by one, we demonstrate that each
Koike, Masafumi, Ota, Toshihiko, Saito, Masako, Sato, Joe   +3 more
core   +3 more sources

Functional Equations and Fourier Analysis

, 2010
By exploring the relations among functional equations, harmonic analysis and representation theory, we give a unified and very accessible approach to solve three important functional equations -- the d'Alembert equation, the Wilson equation, and the d ...
Akkouchi, An, An, Davison, Dilian Yang, Folland   +5 more
core   +1 more source

Comparative analysis of imaging configurations and objectives for Fourier microscopy [PDF]

, 2015
Fourier microscopy is becoming an increasingly important tool for the analysis of optical nanostructures and quantum emitters. However, achieving quantitative Fourier space measurements requires a thorough understanding of the impact of aberrations ...
Jiang, Mingming, Kurvits, Jonathan A., Zia, Rashid   +2 more
core   +1 more source

On twisted Fourier analysis and convergence of Fourier series on discrete groups

, 2008
We study norm convergence and summability of Fourier series in the setting of reduced twisted group $C^*$-algebras of discrete groups. For amenable groups, F{\o}lner nets give the key to Fej\'er summation.
A. Connes, A. Connes, A. Figà-Talamanca, A. Kleppner, A. Kleppner, A. Paterson, A. Valette, A. Valette, A. Valette, A.L. Carey, A.Yu. Ol’shanskiĭ, B. Dorofaeff, C. Berg, C. Nebbia, C.A. Akemann, E. Bédos, E. Ghys, E.G. Effros, Erik Bédos, F. Luef, F. Luef, G. Fendler, G. Fendler, G. Mackey, G. Pisier, G. Zeller-Meier, I. Chatterji, J. Bellissard, J. Bellissard, J. Brodzki, J. Cannière de, J. Dixmier, J. Dixmier, J. Dixmier, J.-L. Sauvageot, J.-L. Sauvageot, J.A. Packer, J.A. Packer, J.A. Packer, J.A. Packer, J.A. Packer, J.E. Humphreys, J.M. Cohen, J.P. Pier, K. Gröchenig, K.R. Davidson, L.B. Schweitzer, M. Bożejko, M. Bożejko, M. Bożejko, M. Bożejko, M. Bożejko, M. Cowling, M. Cowling, M. Cowling, M. Gromov, M. Leinert, M. Marcolli, M.A. Picardello, N. Higson, N. Ozawa, N. Weaver, N.B. Backhouse, N.B. Backhouse, P. Eymard, P. Jolissaint, P. Jolissaint, P. Jolissaint, P. la Harpe de, P. la Harpe de, P. la Harpe de, P.-A. Cherix, R. Exel, R. Ji, R. Mercer, R.B. Howlett, Roberto Conti, S. Wagon, T. Januszkiewicz, U. Haagerup, U. Haagerup, V. Flory, V. Mathai, V. Paulsen, X. Chen   +84 more
core   +2 more sources

An approach for coherent periodogram averaging of tilt‐series data for improved contrast transfer function estimation

FEBS Open Bio, EarlyView.
The contrast transfer function (CTF) is an imaging aberration that is a major resolution‐limiting factor in cryo‐electron microscopy (cryo‐EM). Precise CTF estimation is key to overcoming this limitation, but is particularly challenging in cryo‐electron tomography (cryo‐ET) data. Here, we present an approach for using geometric information to assist in
Sagar Khavnekar, William Wan
wiley   +1 more source

Threshold Values of Sleep Spindles Features in Healthy Adults Using Scalp‐EEG and Associations With Sleep Parameters

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Sleep spindles are an electrophysiological fingerprint of the sleeping human brain. They can be described in terms of duration, frequency, amplitude, and density, and vary widely according to age and sex. Spindles play a role in sleep and wake functions and are altered in several neurological and psychiatric disorders.
Julien Coelho, Heloïse Degros, Jean‐Arthur Micoulaud‐Franchi, Patricia Sagaspe, Emmanuel d'Incau, Paul Galvez, Christian Berthomier, Pierre Philip, Jacques Taillard   +8 more
wiley   +1 more source

Some extremal functions in Fourier analysis, III

, 2008
We obtain the best approximation in $L^1(\R)$, by entire functions of exponential type, for a class of even functions that includes $e^{-\lambda|x|}$, where $\lambda >0$, $\log |x|$ and $|x|^{\alpha}$, where $-1 < \alpha < 1$.
A. Selberg, A. Zygmund, D.S. Lubinsky, Emanuel Carneiro, F. Littmann, F. Littmann, H.L. Montgomery, J. Holt, J.D. Vaaler, J.T. Barton, Jeffrey D. Vaaler, M. Ganzburg, M. Ganzburg, M. Plancherel, R.M. Young, S.W. Graham, W. Rudin, X.J. Li   +17 more
core   +2 more sources