SONAR Sound Navigation and

Composites having 1-3 connectivity are successfully exploited in sonar ( sound navigation and ranging ), medical imaging technologies, NDT, etc. Important matters crucial to the satisfactory functioning of a 1-3 composite are briefly summarized below where, to illustrate the ideas, it is assumed the composite is operating as a sonar device, that is under hydrostatic conditions. The subject matter is discussed in detail by W.A. Smith [16]. 

The addition of salt to water increases the viscosity of water. This is caused by the electrostatic attraction between the solutes and water. Because of slight spatial differences in salinity, the viscosity, and, hence, the speed of sound in seawater is also geographically variable. This is of practical consequence because the operation of SONAR (Sound Navigation Ranging) depends on a precise knowledge of the speed of sound in seawater. As described in Chapter 1, World War II made the need for accurate SONAR essential. This demand motivated the first detailed studies of the distribution of salinity and temperature in the ocean, which marked the beginning of the modern age of oceanography. 

Sonar. Acronym for SOund NAvigation and RaneiTig. A communication and nosition-... 

Sonar system Sound navigation and ranging system... 

SONAR Acronym for sound navigation and ranging, adapted in the 1940s, involves the use of sound to... 

Sonar, acronym for SOund Navigation And Ranging, a detection system based on the reflection of underwater sound waves. A typical sonar system emits ultrasonic pulses by using... 

In navigation and target detection, a scanning active sonar can be used to provide a realistic visual picture of sound-reflecting objects around the source. The scanning beam is rotated, and the reflected beams show the position of objects in a given plane as echo blips . Another display is required to show the depth/altitude of the object observed... 

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