J. A. Shorey
L. W. Nolte
Dept. of Elec. Eng., Box 90291, Duke Univ., Durham, NC 27708-0291
An optimal a posteriori probability approach to matched field processing using time domain data in the form of arrival times is implemented. The inherent robustness of this technique is demonstrated with respect to conventional narrow-band frequency domain based matched field processing techniques. A ray-tracing method and a wideband normal mode method are compared as modeling mechanisms for this application. Localization performance for a shallow-water source localization problem is presented using probabilities of correct localization. Specific results for this shallow-water environment are presented as a function of signal-to-noise ratio. [Research sponsored by ONR Ocean Acoustics and NUWC.]
Standards Committee S12 on Noise. Working group chairs will report on their progress for the production of noise standards. The interaction with ISO/TC 43/SC1 and ISO/TC 94/SC12 activities will also be discussed, with reference to the international standards under preparation. The Chairs of the respective U.S. Technical Advisory Groups (H. E. von Gierke and E. H. Berger) will report on current activities of these International Technical Subcommittees under ISO and the meeting of ISO/TC 43/SC1, held in London, U.K. in November 1994. Scope of S12: Standards, specifications and terminology in the field of acoustical noise pertaining to methods of measurement, evaluation and control; including biological safety, tolerance and comfort and physical acoustics as related to environmental and occupational noise.
Standards Committee S1 on Acoustics. Working group chairs will report on their preparation of standards on methods of measurement and testing, and terminology, in physical acoustics, electroacoustics, sonics, ultrasonics, and underwater sound. Work in progress includes measurement of noise sources, noise dosimeters, integrating sound-level meters, and revision and extension of sound level meter specifications. Open discussion of committee reports is encouraged. The international activities in ISO/TC 43 Acoustics, and IEC/TC 29 Electroacoustics, will also be discussed. The chairs of the respective U.S. Technical Advisory Groups for ISO/TC 43 (H. E. von Gierke), and IEC/TC 29 (V. Nedzelnitsky), will report on current activities of these Technical Committees, including their most recent meetings. (ISO/TC 43 and IEC/TC 29 both met in London, U.K. during November 1994). Scope of S1: Standards, specifications, methods of measurement and test and terminology in the field of physical acoustics including architectural acoustics, electroacoustics, sonics and ultrasonics, and underwater sound, but excluding those aspects which pertain to biological safety, tolerance and comfort.