The effect of geoacoustic characteristics of the bottom on the long-range sound propagation in an inhomogeneous ocean

The long-range sound propagation from a deep ocean to a receiving system located on the shelf is modeled. The waveguide model is constructed on the basis of the data of an acoustic-oceanographic experiment carried out in the northwestern Pacific. The sensitivity and the frequency dependence of the difference in the sound field levels at the crossing of the frontal zone on the geoacoustic characteristics of the bottom of the shelf and the continental slope are investigated. It is shown that the level difference decreases by 8.2 dB as the velocity of longitudinal waves increases by 100 m/s in the range within 1490–1820 m/s.     

The application of the construction of Kolmogorov complexity and of a theorem by Maslov to semiotic systems

The results obtained in V. P. Maslov’s article [1] can automatically be carried over to arbitrary semiotic systems if the string of signs is sufficiently long. We shall show in this article, by using arguments based on the ideas of Kolmogorov complexity and by applying the theorem of V. P. Maslov from [2], that one can obtain similar formulas for the distribution of various semiotic objects. In order to do this, we must introduce notions generalizing the occurrence frequency of words in corpora of texts. We also interpret a formula due to Maslov (appearing in [3]) from the point of view of the general semiotic notions introduced here.     

Factor and term ranks for matrix union over semirings

We consider the arithmetic properties of the factor-rank and term-rank functions for matrices over semirings. In particular, we investigate the sets of matrices that satisfy the extremes of inequalities for these rank functions of matrix union. The classification of the linear transformations that keep these sets invariant is obtained. __________ Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 9, No. 3, pp. 175–197, 2003.     

On entire nonnegative solutions of quasilinear inequalities of elliptic type that vanish on a set of positive measure

In the article, it is proved that any nonnegative solution of an elliptic quasilinear inequality that vanishes on a subset of positive measure is trivial. __________ Translated from Trudy Seminara imeni I. G. Petrovskogo, No. 25, pp. 112–118, 2005.     

Prognostication of aging of polymeric composite materials

Experimental data demonstrate that a study of accelerated aging can enable prognostication of the working capacity and storage life of polymeric formulations used in aircraft components on the basis of changes in thermogravimetric constants of these polymeric formulations.     

A critical review of the chemical kinetics of SF4, SF5, and S2F10 in the gas phase

The gas phase chemical kinetics of SF₄, SF₅, and S₂F₁₀ are reviewed with particular emphasis on relevance to the general problem of the dielectric breakdown of SF₆. Specific reaction systems treated are SF₄ + F₂, SF₅ + SF₅, and the pyrolysis of S₂F₁₀. Computer modeling calculations were carried out to arrive at the best estimates of rate parameters. Based on the results of these calculations, sets of recommended rate parameters are provided. The major discrepancies and problems in establishing the kinetic data base are described. Thermochemical consequences of different model calculations are given.     

Fundamental aspects of initiated oxidation of tridecane and polyethylene in solutions

Specific features of the initiated oxidation of polyethylene and its low-molecular-weight analogue tridecane, associated with the occurrence of the process in the short-chain mode, were studied.     

Coagulation in lipid- and protein-containing systems

The behavior of real disperse systems with organic impurities was examined under conditions of destabilization by inorganic coagulants. A number of physicochemical methods of analysis and a simulation method were used to identify the character and type of the complexes formed and to calculate their stability constants.     

Effects of tributyltin(IV) chloride on the gametes and fertilization of Ascidia malaca (Ascidiacea: Tunicata)

Ascidia malaca gametes before fertilization incubated in 10^?5 or 10^?7 M solutions of tributyltin(IV) chloride, TBTCl, for 3 h appear highly damaged under transmission electron microscopy observation. Also, the fertilization process is affected by the compound: the damaged spermatozoa are present in the vitelline coat and the egg does not cleave. An increase of microbodies, structurally similar to peroxisomes, have been detected in the egg peripheral cytoplasm, probably in relation to their role in alleviating damage to some cellular components. The results have shown that the reproduction of ascidians under unfavourable environmental conditions is prevented. Copyright © 2003 John Wiley & Sons, Ltd.