![]() We discuss here the main features of the whole methodology developed and we also present the experimental results obtained at laboratory scale. Furthermore, the combination of the prototype with a depth sensor enables a wide range of applications, including the 3-D volumetric reconstruction of the scene under study as well as the capability of autonomously determining if an object is occluding the located radioactive sources. The 3-D Cartesian coordinates of the sources are provided even when they are hidden behind an occluding material, such as a wall, or inside a barrel. The technique described in this paper allows the automatic estimation of the distances between the prototype and the located radioactive sources by using triangulation based on epipolar geometry. Key words: thickness structure, Macedonian pine plantations, variation curve, rule of WeisseĪ portable stereo gamma camera has been built, based on two hybrid pixelated detectors, each of them comprising a 1 mm thick CdTe substrate bump-bonded to the Timepix readout chip, a pixelated CMOS ASIC consisting of 256 × 256 pixels with 55µm pitch. It is recommended to be used the established percentage 51.3 or its round value 50% from the thin trees and not its 57.8% value. The table values of 2, relating to a level of significance P=5.0% are several times bigger which shows insignificant differences between the studied rows and the variation curves can be successfully compared.Īt the studied Macedonian pine plantations the rule of Weisse (1880) is not valid. The 2 method is suitable for the following of the differences between the compared levels of the variation curves of the Macedonian pine stands. For the Macedonian pine plantations the variation curve is with a wider interval with 0.2 points (from 0.3 to 1.7) and with more clearly expressed maximum at the average diameter (15.8%) compensated with higher representation of the thin trees to natural levels of thickness 0.7 and in the range of the thicker ones from 1.1 to 1.7. The thickness structure of the studied Macedonian pine plantations differs from this one of the pure natural stands established by Tyurin in 1931. The basic material for the study has been collected in the region of the mountain hut Aleko in the area Brezovitsa in the Vitosha mountain in a part of the Macedonian pine plantations out of the species natural habitat established in 1934 on a north-eastern slope at an altitude 1650 m a.s.l. ![]() ![]() Hence, this work can be considered a continuously added value to previous investigations for scintimammography imaging. Moreover, the calculated full width at half maximum (FWHM) and contrast for decoded images (having average values of 8 and 3.5 for TBR between 2 and 10) permitted us to conclude that we can accurately localize small lesions up to lower TBR values by following the decoding procedure of deducing the image of a “blank phantom” (phantom with TBR = 1) every time within a matlab-based program. Good agreement has been seen for the benchmark stage, especially in terms of tumor localization. Second, we virtually extend our work by changing the tumor-to-background (TBR) and lesion location parameters. First, we compare the experimental data against the simulation results carried out using Geant4 (version 10.4) and accreditation phantom. In this paper, we propose an experimental study and Geant4 simulations of MURA mask breast imaging. Gamma rays have been extensively investigated for breast imaging using collimators however, the coded-aperture technique needs to be investigated more.
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