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We have calculated by using CARI-7A the effective and ambient radiation doses absorbed by a reference human phantom inside aircrafts with cruise speed, and averaged ascent/descent rates as presented by real airplanes such as: Airbus 380, Boeing 777, 787, Hercules C-130 and Twin Otter DHC-6, in a sample of flight aerial routes in a range of flight levels. In the sample, fifteen routes are between the longest non-stop flight around the world, where four flights pass over the Arctic and we have considered one air route involving the Antarctica with two additional special cases. The Earth curvature based on model WGS84 was taken into account for every point in each route by using the INVERSE3D software. Then we constructed radiation dose charts according to the ICRP-103 conditions by using the radiometric results coming from the CARI-7A simulations. These charts present the effective absorbed radiation dose as a function of flight level and flight time in a year of normal operations of the crew as recommended by the FAA. We have also characterized geographically and kinematically the cosmic effective radiation absorption rates at Earth's atmosphere in terms of the structure and order of polynomials in the altitude. From the flight with the leading rate of irradiation we found a thumb rule to estimate the effective absorbed radiation dose and the ambient equivalent dose that gives a superior threshold for any flight of the sample and perhaps on Earth, valid in altitude interval [20000, 50000] ft., Comment: 20 pages, 52 figures, 7 tables

In this study we numerically calculate the spatial profile of mechanical strain on self-assembled germanium (Ge) quantum dots (QDs) grown on a silicon (Si) substrate. Although the topic has been exhaustively studied, interesting features have not been explained or even mentioned in the literature yet. We studied the effect of the cap layer considering two cases: capped QDs (where a Si cap is present above the Ge QDs) and uncapped QDs (where no Si is present above the Ge QDs). We observed that Ge in the capped QDs is more strained compared with the the uncapped QDs. This expected effect is attributed to the additional tension from the Si cap layer. However, the situation is opposite for the Si substrate, it is more strained in the uncapped QD because the Ge layer is less strained in this case. We also calculated the band-edge alignment for the electrons and holes., Comment: 6 pages, 8 figures