香港六合彩开奖/CD TS 13604

Projet

Examen du projet par le comit茅 en cours.

搁茅蝉耻尘茅

The methodology for the standard-target calibration of active sonar systems used for imaging and for measuring scattering will be elaborated for eventual standardization in measurement protocols for individual sonars. This applies to echo sounders, multibeam sonars, sidescan sonars, parametric sonars, and other active sonar systems. The nominal span of sonar operating frequencies is from 1 kHz to several megahertz, including both narrowband and broadband signals. Excluded from the standard are active sonars whose output cannot be calibrated because of uncontrolled processes.