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In the article two series of ballistic experiments conducted according to the scheme of electrothermal chemical control of ballistic parameters of the shot at the Research Institute of Applied Mathematics and Mechanics of Tomsk State University (RIAMM TSU, Russia) are considered. The experimental part of the work is described. The analysis of the electro physical data of ballistic experiments is carried out. A methodical approach that allows to take into account the entry of an electric discharge plasma in a gunpowder in the mathematical model of internal ballistic processes in barrel systems is proposed and tested. Under the conditions of these experiments, the effects of various characteristics of the plasmatron on the nature of the energy entry are estimated. [ABSTRACT FROM AUTHOR]

A series of DOP tests with lateral confinement have been carried out and a linear relation between the residual penetration in RHA and the alumina thickness has been obtained. The rod configuration and the initial transient impact are the two factors that cause the gradual decrease of the differential efficiency factor (DEF) when the ceramic thickness is increased in literature. A new improved DEF definition is proposed to characterize the thick tile ceramic ballistic performance based on a more physical analysis. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The technique of Digital Speckle Radiography (DSR) has been shown to be widely applicable to the field of ballistics through its ability to measure internal displacement fields to a high precision. In a DSR experiment, a flat plane, typically 500 μm thick, of X-ray opaque filings are introduced into the sample during manufacture. Flash X-rays can then be used to image the plane, both before and during an impact event, to produce random speckled images on an X-ray film. Small sub-regions of the images can be tracked relative to each other using a Digital Speckle Photography (DSP) correlation algorithm. This produces a displacement field within the specimen on the seeded plane. By repeating an experiment with identical specimens, but varying the delay of the X-ray exposure, a full time history of the impact event can be obtained. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Data from 219 impacts of L/D =1 projectiles into semi-infinite targets of the same material have been analyzed to determine the ratio of the crater radius, R, to penetration depth, P. The most interesting result is that R/P ≠ 1.0, as is usually assumed. The analysis also shows that R/P is independent of impact velocity over the range from less than 1 km/s to more than 8 km/s. Statistical analysis gives R/P = 0.93 with a standard error of ± 0.07. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

In our previously developed thermoballistic description of electron transport in semiconductor structures, the ballistic and diffusive transport mechanisms are unified. By allowing spin relaxation to take place during the ballistic electron motion between randomly distributed equilibration points, a thermoballistic spin-polarized current is constructed. Here, we adopt the thermoballistic description to treat spin-polarized transport in heterostructures formed of a nonmagnetic semiconducting sample sandwiched between two finite-width layers of diluted magnetic semiconductors. We evaluate the magnetoresistance and the current spin polarization for a specific case and compare the results to those of a purely diffusive treatment. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]