发布求助
文献互助 智能选刊 最新文献

2019 Days on Diffraction (DD)最新文献

筛选
英文 中文
Electromagnetic waves scattering from infinite periodic arrays of thin absorbing wires 电磁波从无限周期阵列的薄吸收线散射
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016584
V. Zalipaev, A. Matveentsev, A. Rzhevskiy
{"title":"Electromagnetic waves scattering from infinite periodic arrays of thin absorbing wires","authors":"V. Zalipaev, A. Matveentsev, A. Rzhevskiy","doi":"10.1109/DD46733.2019.9016584","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016584","url":null,"abstract":"Resonance absorption of the electromagnetic waves reflected from the infinite perfectly conducting screen covered with different layered structures of thin absorbing wires is studied. In the first case a structure represents a set of planar infinite 1D arrays of parallel infinitely long absorbing thin wires. In the second case a single mesh consists of the infinite 2D array of finite in length absorbing thin wires. For both problems the quasi-periodic electromagnetic wave field involves the incident and the specular reflected from the screen two plane waves as well as the diffracted field which is constructed as a superposition of the interacting wave fields irradiated by the induced electric currents of thin wires. The approach that allows us to calculate the diffracted field is based on the method of the integral equations of the Pocklington type suitable in the case of the thin wire approximation. The key point in this study is the analysis of the frequency spectrum of the reflected energy flux. A few cases of resonance absorption of the wave reflected from the screen covered with the layered structures are demonstrated numerically. The described layered structures represent the simplest construction in the sense of technology of manufacturing radio-absorbing surfaces that could be used in radio-location to reduce the monostatic radar cross section of various metallic objects of large size.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121536803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Investigation of emission illusion at the angle 角度发射错觉的研究
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016495
V. Soboleva, A. Vozianova, M.A. Inyakin, M. Khodzitsky
{"title":"Investigation of emission illusion at the angle","authors":"V. Soboleva, A. Vozianova, M.A. Inyakin, M. Khodzitsky","doi":"10.1109/DD46733.2019.9016495","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016495","url":null,"abstract":"Transformation optics devices that create an illusion of a radiation point source at a some distance from a real source are used to confuse radar detectors. Permittivity and permeability of material which stretches radiation source along angular co-ordinate are calculated. Numerical simulation of illusion device was made using the finite element method and the existence of two visible illusions is proved. Influence of material properties of the illusion device and the source position on the illusion effect are studied.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116660961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Normal mode coupling in a waveguide with a range-dependent sound speed profile in the bottom 底部声速随距离变化的波导中的正模耦合
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016564
A. Lunkov, M. Volkov, V. Petnikov, V. A. Grigoriev
{"title":"Normal mode coupling in a waveguide with a range-dependent sound speed profile in the bottom","authors":"A. Lunkov, M. Volkov, V. Petnikov, V. A. Grigoriev","doi":"10.1109/DD46733.2019.9016564","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016564","url":null,"abstract":"Sound propagation in shallow water over the bottom with a varying impedance is considered in the coupled normal mode approach. Water depth is assumed to be constant. Bottom roughness is not taken into account. Range-dependent impedance is only associated with the spatial variability of sound speed in the bottom. The results of 3D seismic survey conducted in the Kara Sea are taken as an input data for sound propagation modeling. Numerical simulations show that the typical horizontal gradients ~ 0.4 s−1 of the bottom sound speed provide mode coupling.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124785385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the solution of the problem of low-frequency acoustic signal propagation in a shallow-water waveguide with three-dimensional random inhomogeneities 具有三维随机非均匀性的浅水波导中低频声信号传播问题的求解
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016423
O. Gulin, I. Yaroshchuk
{"title":"On the solution of the problem of low-frequency acoustic signal propagation in a shallow-water waveguide with three-dimensional random inhomogeneities","authors":"O. Gulin, I. Yaroshchuk","doi":"10.1109/DD46733.2019.9016423","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016423","url":null,"abstract":"Based on the local mode method, the problem of the propagation of tonal acoustic signals of a frequency f <1 kHz in a shallow water waveguide typical for the shelf zones of an ocean is considered in the presence of three-dimensional random fluctuations of the sound speed in the water column. Three-dimensional linear acoustics equations with random coefficients are reformulated into causal equations of the first order, for which, by analogy with the two-dimensional case, the solution can be written in quadratures in a convenient exponential representation. As applied to the problem of fluctuations of the speed of sound in a waveguide, a solution is written in the one-way propagation approximation (forward scattering), on the basis of which it is possible to perform statistical modeling. In the particular case, an example illustrating the statistical calculations of the average transmission loss of the signal frequency of 500 Hz is presented.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126495851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Ocean bathymetry as an inverse problem for the radiative transfer equation 海洋测深作为辐射传递方程的反问题
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016589
A. Sushchenko, V. Kan, E. Liu
{"title":"Ocean bathymetry as an inverse problem for the radiative transfer equation","authors":"A. Sushchenko, V. Kan, E. Liu","doi":"10.1109/DD46733.2019.9016589","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016589","url":null,"abstract":"We consider the bathymetry problem which is based on the mathematical model of the acoustic signal propagation in a fluctuating medium. Solution of the direct problem for determination of the flux density is obtained in the double scattering approximation. The inverse problem is formulated as determination of the function describing deviation from a reference value. As a solution to the problem, a non-linear differential equation is obtained with some assumptions for the directivity pattern of the receiving antenna. A numerical analysis of the bathymetry problem is conducted, and the influence of a double scattering signal on the reconstruction of the bathymetric function is investigated.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128459937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Reconstruction of solution to a hyperbolic equation from boundary data 用边界数据重建双曲方程的解
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016468
M. N. Demchenko
{"title":"Reconstruction of solution to a hyperbolic equation from boundary data","authors":"M. N. Demchenko","doi":"10.1109/DD46733.2019.9016468","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016468","url":null,"abstract":"We deal with the problem of determining a solution to a certain hyperbolic equation considered in Ω×ℝ, Ω ⊂ ℝ3. A solution u is to be recovered in some part of the cylinder Ω×ℝ from Cauchy data u, ∂νu given on S × I, where S ⊂ ∂Ω is a part of the boundary, I ⊂ ℝ is a time interval. We provide a reconstruction algorithm for this problem based on analytic expressions.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130374179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Non-recursive formula for trace of heat kernel 热核轨迹的非递归公式
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016557
A. Ivanov, N. V. Kharuk
{"title":"Non-recursive formula for trace of heat kernel","authors":"A. Ivanov, N. V. Kharuk","doi":"10.1109/DD46733.2019.9016557","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016557","url":null,"abstract":"The Seeley–DeWitt coefficients of a heat kernel of Laplace operator satisfy a system of equations of a special form. In this paper we present a new non-recursive formula for the diagonal part of the solution of such recurrence system, which can be used for the Laplace operator with arbitrary smooth Riemann and gauge connections and a potential.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"145 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130679672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Covering of elliptic curves and Fuchsian equations 椭圆曲线与Fuchsian方程的复盖
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016464
A. Smirnov
{"title":"Covering of elliptic curves and Fuchsian equations","authors":"A. Smirnov","doi":"10.1109/DD46733.2019.9016464","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016464","url":null,"abstract":"The paper presents a method for constructing hyperelliptic integrals that are reducible to elliptic. Picard–Fuchs equations for integrals of known reducible hyperelliptic differentials are found. Numerous examples of reducible hyperelliptic integrals of the first and the second kind, and examples of Picard–Fuchs equations that have solutions in the form of hyperelliptic integrals are given.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124400451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Bidimensional analysis of the PROTO-SPHERA flow PROTO-SPHERA流动的二维分析
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016419
B. Tirozzi, P. Buratti, F. Alladio, P. Micozzi
{"title":"Bidimensional analysis of the PROTO-SPHERA flow","authors":"B. Tirozzi, P. Buratti, F. Alladio, P. Micozzi","doi":"10.1109/DD46733.2019.9016419","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016419","url":null,"abstract":"We analyze the temperature distribution on the vertical axis of an axisymmetrical plasma, the radial temperature being almost constant. We solve the equation for the temperature analytically. Further we investigate the bidimensional flow inside the plasma, showing the existence of a convective cell. The considered plasma is the central column of the PROTO-SPHERA configuration, which aims at forming a confined plasma torus around the central plasma discharge.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117183877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Multibump trajectories of adiabatically perturbed periodic Hamiltonian systems with pitchfork bifurcations 具有干草叉分叉的绝热摄动周期哈密顿系统的多碰撞轨迹
2019 Days on Diffraction (DD) Pub Date : 2019-06-01 DOI: 10.1109/DD46733.2019.9016558
A. Ivanov, P. Panteleeva
{"title":"Multibump trajectories of adiabatically perturbed periodic Hamiltonian systems with pitchfork bifurcations","authors":"A. Ivanov, P. Panteleeva","doi":"10.1109/DD46733.2019.9016558","DOIUrl":"https://doi.org/10.1109/DD46733.2019.9016558","url":null,"abstract":"We study a $1tfrac{1}{2}$-degrees of freedom Hamiltonian system with a potential $U(x,varepsilon t) = tfrac{1}{2}(varphi (varepsilon t)x^2 - x^4)$ slowly varying with time. It is assumed that the factor φ(τ) is a periodic function with simple zeroes on its period. Using WKB-method together with a modification of the Melnikov method, we prove that in the adiabatic limit a cascade of bifurcations, occuring when the factor φ passes through the zero value, leads to the existence of transversal homoclinic intersections and multibump trajectories of the system.","PeriodicalId":319575,"journal":{"name":"2019 Days on Diffraction (DD)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130857634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信