Zobrazeno 1 - 10
of 84
pro vyhledávání: '"Roger H. Hackman"'
Autor:
Raymond Lim, Roger H. Hackman
Publikováno v:
Radio Science. 29:1035-1049
A spheroidal coordinate based T matrix formalism is developed for the description of elastic wave scattering from a collection of obstacles embedded in a homogeneous, unbounded medium. The development of the spheroidal formalism for the scattering fr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e877a705916737ec37b37c8debb3be54
https://doi.org/10.1029/94rs00973
https://doi.org/10.1029/94rs00973
Publikováno v:
The Journal of the Acoustical Society of America. 93:1762-1783
The scattering of sound by objects buried in underwater sediments is studied in the context of an exactly soluble model. The model consists of two fluid half‐spaces separated by a planar, fluid, transition layer of arbitrary thickness. Attenuation
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1fc709cdea4c366a6e4d7a6e613a25f4
https://doi.org/10.1121/1.406719
https://doi.org/10.1121/1.406719
Autor:
Kevin L. Williams, Roger H. Hackman
Publikováno v:
The Journal of the Acoustical Society of America. 91:1375-1382
An experimental/theoretical study of the scattering from large aspect ratio, finite elastic cylinders is presented. The study focuses on the excitation mechanisms of the axisymmetric resonances. It is found that significant coupling of the incident f
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c152e771637c6f925787e9b0efad6046
https://doi.org/10.1121/1.402467
https://doi.org/10.1121/1.402467
Autor:
Roger H. Hackman, Raymond Lim
Publikováno v:
The Journal of the Acoustical Society of America. 91:613-638
The acoustic scattering from many interacting, bounded, three‐dimensional obstacles has been treated by several authors [see, for example, V. Twersky, J. Math. Phys. 8, 589 (1967) or B. Peterson and S. Strom, J. Acoust. Soc. Am. 56, 771 (1974)]. In
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9e5f3d1b5b1abb7048c0b0a4dd6a11b3
https://doi.org/10.1121/1.402523
https://doi.org/10.1121/1.402523
Autor:
Gary S. Sammelmann, Roger H. Hackman
Publikováno v:
The Journal of the Acoustical Society of America. 90:2705-2717
Previously, a fundamentally oriented analysis was presented of the complex‐ka plane pole structure of the S matrix for a thin spherical shell for 0
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4b6bc8dedb87abba9472fbb792601dc2
https://doi.org/10.1121/1.401866
https://doi.org/10.1121/1.401866
Autor:
Roger H. Hackman, Gary S. Sammelmann
Publikováno v:
The Journal of the Acoustical Society of America. 89:2096-2103
This article presents a fundamentally oriented analysis of the complex-ka plane pole structure of the S matrix for spherical shells in the thickness range 0.02a⩽h⩽0.10a (a is the outer radius of the sphere) for the high-frequency region (100
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a0921c145d0e10fac129f1156606441d
https://doi.org/10.1121/1.400902
https://doi.org/10.1121/1.400902
Autor:
Raymond Lim, Roger H. Hackman
Publikováno v:
The Journal of the Acoustical Society of America. 87:1076-1103
The fundamental attenuation mechanisms operating in a particular class of composites are investigated for their viability as underwater anechoic materials. The type of composites of interest consists of dense (visco‐) elastic inclusions in rigid, l
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::890c8639eab0bf198914fa4fc12ec788
https://doi.org/10.1121/1.398834
https://doi.org/10.1121/1.398834
Autor:
Roger H. Hackman, Raymond Lim
Publikováno v:
The Journal of the Acoustical Society of America. 87:1070-1075
The basic formulas for the calculation of cross sections for elastic‐wave scattering from elastic and viscoelastic bodies are reviewed from a simpler perspective than normally encountered, with an emphasis toward casting them into a form suitable f
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3d9ddca31f86bdd915fd4dde17ee9553
https://doi.org/10.1121/1.398833
https://doi.org/10.1121/1.398833
Publikováno v:
SPIE Proceedings.
Active acoustic classification of underwater targets is an important problem of current interest. The echo return of such objects has components related to such distinct dynamical elements as the specular (geometric) return, reradiation of elastic re
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6b3ba0c1e7c0012c8207f1feb830cc25
https://doi.org/10.1117/12.160607
https://doi.org/10.1117/12.160607
Autor:
Gary S. Sammelmann, Roger H. Hackman
Publikováno v:
SPIE Proceedings.
This article uses the formalism of Hackman and Sammelmann [J. Acous. Soc. Am., 80(5), pp. 1447-1458] to calculate the scattering from an elastic shell in a shallow water waveguide. This formalism is an exact solution of the Helmholtz Integral Equatio
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6d651c0d35e743c9ea83f844530cb6d5
https://doi.org/10.1117/12.160611
https://doi.org/10.1117/12.160611