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The purpose of this study was to calculate the safety factor in three scenarios represented by three slopes (fronts I, II and III) in order to specify the stability condition of slopes from Castellano polymetallic deposit and under two conditions: including the value of the seismic coefficient of the region in the calculations, and not consider it. Slide v.6.0 so ware was used for modeling and calculation. According to the values obtained from the safety factor, the three analyzed scenarios of the Castellano deposit are unstable under both situations of seismicity evaluated. Values of the safety factor obtained, between 0,281 and 0,444, are well below 1,3; which is the limit value for stability. All this shows the need to implement stabilization measures, such as the drainage ditches, considering that they are inactive slopes without mining operations. [ABSTRACT FROM AUTHOR]

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Considering that x-rays emitted in a mammography system are of low energy, it was assumed, herein, that starting from the half-value layer the behavior of the attenuation coefficient as a function of energy has a slow variation being able to approach a constant coefficient. With this consideration the integrated spectrum was obtained starting from the measures of exposition rate normalized for the half value layers of the energy of 26, 28, 30 and 32 kVp, maintaining constant the current of the tube (90 mAs). This integrated spectrum was used as the spectrum of emission of the tube and the entrance spectra and exit were determined for the four irradiation conditions, each one with 60000 photons emitted from the source. Radiation transport and its interaction forms was simulated by the Monte Carlo Method in air and inside the PMMA phantom breast, keeping in mind the actual form of radiography taking used in this technique, In this work we show the spectral distribution of entrance and exit for the fern energies and the distribution in breast depth for energy at 28 KVp in which is observed that in the breast the biggest energy is absorbed in the first 12 mm of depth. This spectral distribution is of fundamental importance for the determination of dosage conversion factors and to obtain the dosage in a mammography exam. [ABSTRACT FROM AUTHOR]

The article presents the quantitative result on the study of local absorption coefficient due to any electrical field value using the Franz-Keldysh theory. It states that the probability distribution function of electric field with consideration on grain size distribution is calculated to consider charged defects. Accordingly, the absorption edge coefficient theoretical results match the experimental ones used in different values of charged density in the grain surface.