Which combination of f and D will give the best image of this structure?

You are asked to select the best ultrasound imaging parameters for imaging a deep-lying small structure. Assume that this object is located at 20 cm depth and is embedded within a homogeneous tissue with sound speed c = 1, 500 m/s and absorption coefficient α = af, where a = 1.0 dB/(cm MHz). Also assume that the system is sensitive to at most a 100 dB signal loss.

You can choose one of three operating frequencies: f = 1 MHz, f = 2 MHz, or f = 5 MHz. Given any frequency, you can choose one of two transducer diameters: D = 1 cm or D = 2 cm. Assume that all transducers have flat faces and use the split-range field pattern approximation (i.e., geometric and far-field approximations in their appropriate ranges). Which combination of f and D will give the best image of this structure? Justify your answer.

find the cost of your paper

Explain why attenuation is not a big problem in PET.

Consider a 2-D object consisting of two triangle compartments, as shown in Figure P9.4. Suppose a solution containing a 511 KeV gamma ray emitting radionuclide with concentration f = 0.5….

Give the mean and the variance of the reconstructed image, mean[ˆ f(x, y)] and var[ˆ f(x, y)].

Ignoring the inverse square law and attenuation, an approximate reconstruction for SPECT imaging is given by where c˜() =  {||W()} and W() is a rectangular windowing filter that cuts off at = 0…..

Find the numerical responses in each to an event in crystal C(4, 6).

Suppose a PET detector comprises four square PMTs (arranged as a 2 by 2 matrix) and a single BGO crystal with slits made in such a way that it is….