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相关论文: Enhanced Approximate Cloaking by SH and FSH Lining

200 篇论文

This is a survey of approximate cloaking using transformation optics for acoustic and electromagnetic waves.

偏微分方程分析 · 数学 2019-02-01 Hoai-Minh Nguyen , Michael S. Vogelius

We construct a regular isotropic approximate cloak for the Maxwell system of equations. The method of transformation optics has enabled the design of electromagnetic parameters that cloak a region from external observation. However, these…

偏微分方程分析 · 数学 2018-05-23 Tuhin Ghosh , Ashwin Tarikere

A cylindrical wave expansion method is developed to obtain the scattering field for an ideal two-dimensional cylindrical invisibility cloak. A near-ideal model of the invisibility cloak is set up to solve the boundary problem at the inner…

光学 · 物理学 2007-09-15 Zhichao Ruan , Min Yan , Curtis W. Neff , Min Qiu

The aim of this paper is to provide an original method of constructing very effective near-cloaking structures for the conductivity problem. These new structures are such that their first Generalized Polarization Tensors vanish. We show…

数学物理 · 物理学 2015-05-27 Habib Ammari , Hyeonbae Kang , Hyundae Lee , Mikyoung Lim

We show an optimal data-dependent hashing scheme for the approximate near neighbor problem. For an $n$-point data set in a $d$-dimensional space our data structure achieves query time $O(d n^{\rho+o(1)})$ and space $O(n^{1+\rho+o(1)} +…

数据结构与算法 · 计算机科学 2015-07-17 Alexandr Andoni , Ilya Razenshteyn

Transformation optics constructions have allowed the design of cloaking devices that steer electromagnetic, acoustic and quantum waves around a region without penetrating it, so that this region is hidden from external observations. The…

偏微分方程分析 · 数学 2015-09-15 Matti Lassas , Ting Zhou

Using the framework of transformation optics, this paper presents a detailed analysis of a non-singular square cloak for acoustic, out-of-plane shear elastic, and electromagnetic waves. The generating map is examined in detail and linked to…

数学物理 · 物理学 2014-01-30 DJ Colquitt , IS Jones , NV Movchan , AB Movchan M Brun , RC McPhedran

This paper is concerned with the invisibility cloaking in electromagnetic wave scattering from a new perspective. We are especially interested in achieving the invisibility cloaking by completely regular and isotropic mediums. Our study is…

数学物理 · 物理学 2017-01-20 Jingzhi Li , Xiaofei Li , Hongyu Liu , Yuliang Wang

In this paper, we develop a general mathematical framework for the electro-osmosis problem to design simultaneous microscale electric and hydrodynamic cloaking in a Hele-Shaw configuration. A novel approach to achieving simultaneously…

偏微分方程分析 · 数学 2024-04-04 Hongyu Liu , Zhi-Qiang Miao , Guang-Hui Zheng

This paper introduces a new sweeping preconditioner for the iterative solution of the variable coefficient Helmholtz equation in two and three dimensions. The algorithms follow the general structure of constructing an approximate $LDL^t$…

数值分析 · 数学 2010-08-03 Björn Engquist , Lexing Ying

In this paper, we develop a general mathematical framework for perfect and approximate hydrodynamic cloaking and shielding of electro-osmotic flow, which is governed by a coupled PDE system via the field-effect electro-osmosis. We first…

偏微分方程分析 · 数学 2023-02-16 Hongyu Liu , Zhi-Qiang Miao , Guang-Hui Zheng

Optimal upper and lower error estimates for strong full-discrete numerical approximations of the stochastic heat equation driven by space-time white noise are obtained. In particular, we establish the optimality of strong convergence rates…

概率论 · 数学 2021-11-02 Sebastian Becker , Benjamin Gess , Arnulf Jentzen , Peter E. Kloeden

Locality-sensitive hashing (LSH) has emerged as the dominant algorithmic technique for similarity search with strong performance guarantees in high-dimensional spaces. A drawback of traditional LSH schemes is that they may have \emph{false…

数据库 · 计算机科学 2016-08-22 Ninh Pham , Rasmus Pagh

We start by a review of the chronology of mathematical results on the Dirichlet-to-Neumann map which paved the way towards the physics of transformational acoustics. We then rederive the expression for the (anisotropic) density and bulk…

数学物理 · 物理学 2011-07-27 Guillaume Dupont , Mohamed Farhat , Andre Diatta , Sebastien Guenneau , Stefan Enoch

We address the problem of verifying neural networks against geometric transformations of the input image, including rotation, scaling, shearing, and translation. The proposed method computes provably sound piecewise linear constraints for…

机器学习 · 计算机科学 2024-09-24 Ben Batten , Yang Zheng , Alessandro De Palma , Panagiotis Kouvaros , Alessio Lomuscio

It is well-known that an algorithm exists which approximates the NP-complete problem of Set Cover within a factor of ln(n), and it was recently proven that this approximation ratio is optimal unless P = NP. This optimality result is the…

计算复杂性 · 计算机科学 2021-11-30 Erika Melder

We study Tikhonov regularization for possibly nonlinear inverse problems with weighted $\ell^1$-penalization. The forward operator, mapping from a sequence space to an arbitrary Banach space, typically an $L^2$-space, is assumed to satisfy…

数值分析 · 数学 2021-10-19 Philip Miller , Thorsten Hohage

We investigate two-dimensional invisibility cloaking via transformation optics approach. The cloaking media possess much more singular parameters than those having been considered for three-dimensional cloaking in literature. Finite energy…

偏微分方程分析 · 数学 2010-06-08 Hongyu Liu , Ting Zhou

The method of coordinate transformation offers a way to realize perfect cloaks, but provides less ability to characterize the performance of a multilayered cloak in practice. Here, we propose an analytical model to predict the performance…

光学 · 物理学 2009-04-30 Sheng Xi , Hongsheng Chen , Baile Zhang , Bae-Ian Wu , Jin Au Kong

Based on a coordinate transformation approach, Pendry {\it et al.} have reported electromagnetically anisotropic and inhomogeneous shells that, in theory, completely shield an interior structure of arbitrary size from electromagnetic fields…