Many scientific articles dealing with the detonation of explosive charges and their effects suppose that the charge is spherical and centrally initiated. Yet, when discussing the blast wave effect, the charge shape and the location of initiation could be as important as the composition or the mass of the considered explosive. Specifically, close to the charge, the shape may cause significant modifications of the pressure field compared to the predictions developed for spherical charges. Experiments have been carried out, using an emulsion explosive, TNT and C4, in order to quantify the shape effect. Unconfined, centrally initiated spherical and cylindrical charges with different length-to-diameter (L/D) ratios have been fired. The pressure in the median plane was recorded for different reduced distances. Results for spherical charges showed excellent agreement with well-known references. The expected change of the pressure field in the median plane of a cylindrical charge was observed, directly linked to the L/D ratio. Peak overpressure magnifications of up to almost 3 have been measured. The dimensions of the zone within which an increase of the blast wave effect is observed, have also been determined. A similar behaviour for TNT and C4 has been demonstrated; but a different behaviour has been observed for the emulsion explosive.
In the presence of massive data coming with high heterogeneity we need to change our statistical thinking and statistical education in order to adapt both - classical statistics and software developments that address new challenges. Significant developments include open data, big data, data visualisation, and they are changing the nature of the evidence that is available, the ways in which it is presented and the skills needed for its interpretation. The amount of information is not the most important issue – the real challenge is the combination of the amount and the complexity of data. Moreover, a need arises to know how uncertain situations should be dealt with and what decisions should be taken when information is insufficient (which can also be observed for large datasets). In the paper we discuss the idea of computational statistics as a new approach to statistical teaching and we try to answer a question: how we can best prepare the next generation of statisticians.
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