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A random surface scattering in a one-mode waveguide is studied in the case when the surface profile has long-range correlations along the waveguide. Analytical treatment of this problem shows that with a proper choice of the surface, one…

Condensed Matter · Physics 2009-11-07 F. M. Izrailev , N. M. Makarov

In this work, we present the design of cycloidal waveguides from a gradient refractive index (GRIN) medium in analogy to the fastest descending problem in classical mechanics. Light rays propagate along cycloids in this medium, of which the…

Optics · Physics 2024-04-04 Xiong Hui , Zijun He , Yangjie Liu

Practically, for all real measuring devices the result of a measurement is a convolution of an input signal with a hardware function of a unit {\phi}. We call a spline to be {\phi}-interpolating if the convolution of an input signal with a…

Data Analysis, Statistics and Probability · Physics 2012-03-05 Oleksandr Shumeyko , Ivan Devyatkin

Surface reconstruction from point clouds is a fundamental step in many applications in computer vision. In this paper, we develop an efficient iterative method on a variational model for the surface reconstruction from point clouds. The…

Numerical Analysis · Mathematics 2020-05-26 Dong Wang

We analyzed the behavior of the complex Fourier spectrum of the angle-resolved light scattering pattern (LSP) of a sphere in the framework of the Wentzel-Kramers-Brillouin (WKB) approximation. Specifically, we showed that the phase value at…

Optics · Physics 2023-01-26 Andrey V. Romanov , Valeri P. Maltsev , Maxim A. Yurkin

Layers with gradient refractive-index profile are an attractive alternative to conventional homogeneous stack coatings. However, the optical characterization and monitoring of the graded refractive-index profile is a complex issue, which…

Optics · Physics 2021-11-03 Vít Kanclíř , Jan Václavík , Karel Žídek

Interstellar scattering causes broadening and distortion to the mean pulse profiles and polarization position angle (PPA) curves, especially to the pulse profiles observed at lower frequency. This paper has implemented a method to recover…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Abdujappar Rusul , Ali Esamdin , Alim Kerim , Dilnur Abdurixit , Hongguang Wang , Xiao-Ping Zheng

We present a direct, index-free method to recover the side lengths of a planar rectangle the spectrum of its Dirichelet Laplacian, assuming only access to a finite subset of eigenvalues. No modal indices $(m,n)$ are available, and the list…

Spectral Theory · Mathematics 2025-12-19 Eldar Sultanow , Andreas Hatziiliou

The inverse problem of amplitude reconstruction on an inclined line based on the values of amplitude or its module as recorded on semi-infinite line orthogonal to the beam propagation direction is considered within the framework of 2D…

Numerical Analysis · Mathematics 2021-05-21 R. M. Feshchenko , I. A. Artyukov , A. V. Vinogradov

In this paper a general theory for interpolation methods on a rectangular grid is introduced. By the use of this theory an efficient B-spline based interpolation method for spectral codes is presented. The theory links the order of the…

Computational Physics · Physics 2012-01-20 M. A. T. van Hinsberg , J. H. M. ten Thije Boonkkamp , F. Toschi , H. J. H. Clercx

The optics of a number of future X-ray telescopes will have very long focal lengths (10 - 20 m), and will consist of a number of nested/stacked thin, grazing-incidence mirrors. The optical quality characterization of a real mirror can be…

Instrumentation and Methods for Astrophysics · Physics 2015-09-09 D. Spiga , S. Basso , M. Bavdaz , V. Burwitz , M. Civitani , O. Citterio , M. Ghigo , G. Hartner , B. Menz , G. Pareschi , L. Proserpio , B. Salmaso , G. Tagliaferri , E. Wille

We revisit the problem of recovering wave speeds and density across a curved interface from reflected wave amplitudes. Such amplitudes have been exploited for decades in (exploration) seismology in this context. However, the analysis in…

Analysis of PDEs · Mathematics 2022-01-10 Sombuddha Bhattacharyya , Maarten V. de Hoop , Vitaly Katsnelson , Gunther Uhlmann

Ray tracing is increasingly utilized in wireless system simulations to estimate channel paths. In large-scale simulations with complex environments, ray tracing at high resolution can be computationally demanding. To reduce the computation,…

Signal Processing · Electrical Eng. & Systems 2026-02-02 Ruibin Chen , Jayadev Joy , Yaqi Hu , Mingsheng Yin , Marco Mezzavilla , Sundeep Rangan

Remote focusing of light in a graded-index medium via mode interference is demonstrated using exact analytical solutions of the wave equation. Strong focusing of light occurs at extremely long distances and it revivals periodically with…

Optics · Physics 2015-12-09 Nikolai I. Petrov

This paper addresses the construction of inverted index for large-scale image retrieval. The inverted index proposed by J. Sivic brings a significant acceleration by reducing distance computations with only a small fraction of the database.…

Computer Vision and Pattern Recognition · Computer Science 2022-06-28 Ying Wang

Preserving details in restoring images highly corrupted by impulse noise remains a challenging problem. We proposed an algorithm based on radial basis functions (RBF) interpolation which estimates the intensities of corrupted pixels by…

Multimedia · Computer Science 2017-02-17 Fariborz Taherkhani , Mansour Jamzad

We demonstrate that a transformation device can be emulated using a gradient-index waveguide. The effective index of the waveguide is spatially varied by tailoring a gradient thickness dielectric waveguide. Based on this technology, we…

Optics · Physics 2015-06-05 Y. Wang , C. Sheng , H. Liu , Y. J. Zheng , C. Zhu , S. M. Wang , S. N. Zhu

We propose a scheme for imaging periodic surfaces using a superlens. By employing an inverse scattering model and the transformed field expansion method, we derive an approximate reconstruction formula for the surface profile, assuming…

Numerical Analysis · Mathematics 2024-03-05 Peijun Li , Yuliang Wang

A method to probe the guiding characteristics of waveguides formed in real-time is proposed and evaluated. It is based on the analysis of the time dependent light distribution observed at the exit face of the waveguide while progressively…

Optics · Physics 2007-09-18 M. Chauvet , G. Fu , G. Salamo

The multichannel trigonometric reconstruction from uniform samples was proposed recently. It not only makes use of multichannel information about the signal but is also capable to generate various kinds of interpolation formulas according…

Classical Analysis and ODEs · Mathematics 2024-12-20 Dong Cheng , Kit Ian Kou
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