Theoretical Analysis of Rough‐Surface Shadowing from Point‐Source Radiation

Mithal and Vera give the impression that the correct cylindrically symmetric slant stack (e.g., Chapman, 1981; Harding, 1985; Brysk and McCowan, 1986a) needed to represent point‐source radiation in vertically stratified media is both expensive and unnecessary in ordinary data analysis.

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Scattering of sound from a point source by a rough surface progressing over an isovelocity ocean

The Journal of the Acoustical Society of America ◽

10.1121/1.380679 ◽

1975 ◽

Vol 58 (2) ◽

pp. 349-364 ◽

Cited By ~ 11

Author(s):

E. Y. Harper ◽

F. M. Labianca

Keyword(s):

Point Source ◽

Rough Surface

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An Endoscopic and Robotic Tooth-like Compliance and Roughness Tactile Sensor

Journal of Mechanical Design ◽

10.1115/1.1471531 ◽

2002 ◽

Vol 124 (3) ◽

pp. 576-582 ◽

Cited By ~ 43

Author(s):

J. Dargahi

Keyword(s):

Surface Roughness ◽

Theoretical Analysis ◽

Rough Surface ◽

Polyvinylidene Fluoride ◽

Tactile Sensor ◽

Relative Deformation ◽

End Effectors ◽

Experimental Values ◽

Robotic Applications

This paper reports on design, fabrication and testing of a prototype Polyvinylidene Fluoride (PVDF) tactile sensor for endoscopic and robotic applications. The sensor can measure both compliance and surface roughness. It consists of rigid and compliant elements. A relative deformation between adjacent parts of the contact object is used to measure the compliance, and the deformation of the compliant element of the sensor is used to measure the profile of a rough surface. The sensor in miniaturized form can be integrated with both endoscopic graspers and robotic end effectors. The theoretical analysis of the sensor is made and compared with experimental values. The advantages and limitations of the sensor are also discussed.

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Radiation patterns: Possibility for monitoring seismic sources

Geophysics ◽

10.1190/1.1443950 ◽

1996 ◽

Vol 61 (1) ◽

pp. 282-287

Author(s):

Philip Carrion ◽

José Carcione ◽

Edson E. S. Sampaio

Keyword(s):

Point Source ◽

Field Measurements ◽

Seismic Sources ◽

Seismic Events ◽

Elastic Media ◽

Radiation Patterns ◽

Source Radiation ◽

Earth Environment ◽

Source Excitation ◽

Homogeneous Media

Recent field measurements of the radiation in boreholes indicate that the radiation patterns of real seismic sources are not always in agreement with those corresponding to the point‐source excitation in unbounded homogeneous and isotropic acoustic or elastic media [we refer the reader to Aki and Richards (1980) for the basic discussion on the radiation patterns in homogeneous media]. This mismatch results from the fact that the point‐source radiation patterns corresponding to homogeneous media are too simplistic to satisfy any experiment in the more realistic Earth environment. A study of radiation patterns is certainly important not only to predict possible seismic events but also to analyze the source performance itself by recording seismic arrivals.

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