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Using the bottom track feature, the track of the boat as well as the cross sectional area is estimated after adjustment for left and right bank areas. The discharge can then be calculated as the dot product between the vector track and the current velocity. The method is in use by hydrographic survey organisations across the world and forms an ...
Doppler measurements using Doppler effect can show the direction of the blood flow and its relative velocity, and color Doppler is the provision of color to help interpret the image, showing, for example, the blood flow toward the probe in one color and that flowing away in another. While the equipment itself is costly, the procedure is not.
Speckle tracking is one of two methods for Strain rate imaging, the other being Tissue Doppler. Twist or torsional deformation define the base-to-apex gradient and is the result of myocardial shearing in the circumferential-longitudinal planes such that, when viewed from the apex, the base rotates in a counterclockwise direction.
Acoustic microscopy is the technique of using sound waves to visualize structures too small to be resolved by the human eye. High and ultra high frequencies up to several gigahertz are used in acoustic microscopes. The reflection and diffraction of sound waves from microscopic structures can yield information not available with light.
Acoustic Doppler velocimetry (ADV) is designed to record instantaneous velocity components at a single-point with a relatively high frequency. Measurements are performed by measuring the velocity of particles in a remote sampling volume based upon the Doppler shift effect.
A Doppler stethoscope is an electronic device that measures the Doppler effect of ultrasound waves reflected from organs within the body. Motion is detected by the change in frequency, due to the Doppler effect, of the reflected waves. Hence the Doppler stethoscope is particularly suited to deal with moving objects such as a beating heart. [28]
the depth (range) of the bottom of the river, lake, or ocean below the transducer. Range the distance between the transducer and the "target" (fish, zooplankton, vegetation, bottom). This is determined by precise timing from sound generation to sound reception (by the transducer). Bottom type; Seabed type; Substrate type; or Sediment type
Functional transcranial Doppler sonography (fTCD) is a neuroimaging tool for measuring cerebral blood flow velocity changes due to neural activation during cognitive tasks. [8] Functional TCD uses pulse-wave Doppler technology to record blood flow velocities in the anterior, middle, and posterior cerebral arteries.