Attenuation measurement on Kuband satellite signal in a tropical site, Fiji is presented. Rain-attenuation prediction by ITU-R and the Crane Global models showed noticeable deviation to the measured values. Unlike the monotonic decrease predicted by these models, exceedance of rain-rate and attenuation in Fiji and other tropical regions showed the presence of breakpoints. For Suva, the breakpoi...

The measurement of radioactivity in environmental samples containing natural radionuclides such as 238U, 232Th, and 40K gamma-ray spectrometry is the most common application. One widely used sample containers for measurements volumetric certain sizes cylindrical geometry. These can be made materials with different densities thicknesses. In this intention, study, effect container, which one many...

Instrumentation for ultrasonic velocity and attenuation measurements in liquids and solids is described. 5 MHz pulse generator is assembled using CMOS integrated circuits (4011, 7414, 74121, and 4010), having pulse width 2 microseconds to 60 microseconds. The wideband receiver is developed using Wideband Low Distortion, High Gain Operational Amplifier (OPA 643). The gain and bandwidth of the re...

From calibrated, weakly scattering tissue phantoms (2-6 mm-1), we extract the attenuation coefficient with an accuracy of 0.8 mm-1 from OCT data in the clinically relevant 'fixed focus' geometry. The data are analyzed using a single scattering model and a recently developed description of the confocal point spread function (PSF). We verify the validity of the single scattering model by a quanti...

There is a growing body of evidence for the use of FDG in the differentiation of malignant from benign disease, staging and grading of malignant disease, differentiating recurrent or residual disease from therapy induced changes, and monitoring the response to therapy. Depending on the clinical question and type of equipment available, the FDG imaging procedure may include: A. Limited Field Tom...