International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450)最新文献_第2页

Direct and inverse problems of the ray tomography on the creeping waves 蠕变波射线层析成像的正逆问题

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902360

A. Krauklis, A. I. Malik, V. Troyan

{"title":"Direct and inverse problems of the ray tomography on the creeping waves","authors":"A. Krauklis, A. I. Malik, V. Troyan","doi":"10.1109/DD.2000.902360","DOIUrl":"https://doi.org/10.1109/DD.2000.902360","url":null,"abstract":"Ray tomography widely applied in the global seismology, exploration geophysics and seismic engineering usually uses body waves. Surface waves are employed rarely, partly because of their more complicated cinematic and dynamical properties. However, it is possible to point out problems whose effective solution can be gained only by surface wave ray tomography. In the paper we consider, by means of numerical modeling, the time inversion of creeping spiral waves. These waves are able to transit along the curved interface for a long distance reaching the shadow. The essential feature of the problem is in the existence of the velocity dependence on the local interface curvature. As it result, an effect just the same as anisotropy, appears. Thus, we are facing a 2D inversion problem for the anisotropic medium. The short wave approximation for the spiral wave velocities, as functions of the interface curvature and frequency, were given in Krauklis (1974). We use this approximation to consider both the direct and the inverse problem. For the time inversion, the method based upon the Tichonov regularisation (Ryzhikov and Troyan 1994) is applied here. From our point of view it affords to take the a priori information into consideration in the most natural way. To avoid the computational difficulties caused by a singularity in the solution, we use a suboptimal procedure.","PeriodicalId":184684,"journal":{"name":"International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116087207","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

Diffraction of electromagnetic waves from the impedance with different perturbations 电磁波在不同扰动下的阻抗衍射

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902356

N. Kirpichnikova, V. Philippov, A. S. Kirpichnikova

引用次数: 0

On transient electromagnetic waves produced by the pulsed radial current moving with the velocity of light 利用脉冲径向电流以光速运动所产生的瞬态电磁波

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902368

I. Simonenko

引用次数: 0

Diffraction of hydroacoustic wave by a short joint of two semi-infinite elastic plates 两个半无限弹性板短接头对水声的衍射

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902352

I. Andronov

引用次数: 0

Unexpected wave in a cylindrical rod placed in the elastic medium 意外波在圆柱形棒中放置于弹性介质中

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902359

P.V. Krauklis, L.A. Krauklis

{"title":"Unexpected wave in a cylindrical rod placed in the elastic medium","authors":"P.V. Krauklis, L.A. Krauklis","doi":"10.1109/DD.2000.902359","DOIUrl":"https://doi.org/10.1109/DD.2000.902359","url":null,"abstract":"Most problems of seismic prospecting deal with structures containing interfaces where different materials adhere to one another. It is usual practice to assume these interfaces to have welded contact across which both stresses and displacements are continuous. In engineering geology there exists the concept of a loosely bound interface at surfaces along which the rigid connection between adjacent parts of the medium is broken, which in some cases results in the arising of an emergency situation. In carrying out mining operations, the diagnostics and localization of surfaces with unwelded contacts by acoustic and seismic methods is an important practical task. Earlier it was shown that in a layer sandwiched between two elastic halfspaces and having an unwelded contact an unusual wave propagates. This wave has a number of interesting properties: the wave spectrum has resonance frequencies; wave group velocity is equal to an intermediate value between the shear (V/sub s/) and longitudinal (V/sub p/) velocities; attenuation of the wave increases when the frequency varies from the resonance frequencies. The important feature of this wave is the enrichment of its spectrum by the resonance frequencies during the wave propagation. Such behavior of the wave can be explained if we consider the problem of reflection and transmission of SV waves incident on the boundary of two media with sliding contact. For incidence of the SV wave at angle /spl phi/=arcsin(V/sub s//V/sub p/) total reflection occurs. Here we show that an interference wave with such properties exists in a circular cylindrical body which has a sliding contact with the surrounding elastic medium.","PeriodicalId":184684,"journal":{"name":"International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125342352","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

Acousto-optic scattering in a single-mode optic fibre 单模光纤中的声光散射

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902353

A.V. Badanin, B. Pavlov, A.A. Pokrovski

引用次数: 0

To the problem of diffraction on a slit: some properties of Schwarzschild's series 狭缝上的衍射问题:史瓦西级数的一些性质

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902367

A. Shanin

引用次数: 5

Polynomial solutions of the third-order Fuchsian linear ODE 三阶Fuchsian线性ODE的多项式解

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902361

A. Melezhik

引用次数: 0

Spectral series of the three-dimensional quantum anharmonic oscillator 三维量子非谐振子的谱级数

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902365

M. Poteryakhin

引用次数: 0

Rigorous mathematical models for the reconstruction of thin films profiles from X-ray intensities 从x射线强度重建薄膜轮廓的严格数学模型

International Seminar Day on Diffraction Millennium Workshop (IEEE Cat. No.00EX450) Pub Date : 1900-01-01 DOI: 10.1109/DD.2000.902369

S. Slavyanov, C. Ern, H. Dosch

引用次数: 1