When an ultrasound beam passes, at an angle other than 90°, from a tissue with a lower speed of sound (C1) to one with a higher speed of sound (C2), the beam will
A. a) Be deflected toward the normal.
B. b) Be deflected away from the normal.
C. c) Remain on its original path.
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Sound waves are mechanical pressure waves made up of
A. a) Highs and Lows.
B. b) Compressions and Rarefactions.
C. c) Maximums and Minimums.
A gradient descent image registration method
A. ) is generally always of the affine registration type.
B. ) will eventually find a correct answer but it might take a large amount of time.
C. ) will continue to change parameters in a given direction while the objective function is decreasing.
When performing image registration, an objective function
A. ) measures the modality of an image.
B. ) gives a measure of the similarity between two overlaid images.
C. ) describes the co-ordinate system between two images.
Data towards the edge of k-space is
A. ) more intense.
B. ) representative of higher frequency responses relative to that at the centre.
C. ) representative of lower frequency responses relative to that at the centre.
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