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An approach to justifying the composition of the reconnaissance-firing systems is proposed, which would consider the appropriate type of redundancy for each subsystem. Reconnaissance subsystems have a triple modular redundancy because this type of redundancy has a high degree of reliability of the received signal and a high probability of faultless work at the initial stage of operation. For the control subsystem, the most appropriate type of redundancy is passive redundancy, because this subsystem, as a rule, has the lowest failure rate among the elements of other subsystems. For the fire support subsystem, the most appropriate type of redundancy is sliding redundancy, because this type of redundancy allows you to ensure the redundancy of a larger number of main elements with a smaller number of spare ones. The application of the mentioned types of redundancy for these subsystems increases the probability of faultless work and saves the resource of redundancy elements. [ABSTRACT FROM AUTHOR]

The results of numerical modeling of air objects detection ranges using the paired ZU-23 anti-aircraft system and millimeter-wave (mm) radar in various combat conditions are presented to address the task of the improvement of air target engagement efficiency. Through extensive modelling, the effective scattering surface (ESS) of 23 mm projectile was determined. The slant ranges values to the firing zones far boundaries were found under various combat conditions. The probabilities of the ZU firing task fulfilment during autonomous actions and when the personnel work out the target designation (TD) from the mm wavelength range radar are calculated. The expediency of the mm wavelength range radars using for the TD formation on ZU is shown. The increment of shell firing efficiency due to the use of mm wavelength range radars is estimated. The obtained approximate expressions, shell firing efficiency indicators values and graphical material are presented. [ABSTRACT FROM AUTHOR]

Aim. The aim of the study was to compare the specificity and sensitivity of responses of stress and toxicity to Cpz in marine and freshwater species of bivalve molluscs. Methods. The bivalve molluscs Mytilus galloprovincialis and Unio tumidus were collected in Messina, Italy and Ternopil region, Ukraine correspondingly. Two low Cpz concentrations (Cpz I: 12 ng L–1; Cpz II: 12 (M. galloprovincialis) or 18 (U. tumidus) μg L–1) were administered to molluscs for 14 days. The set of 16 studied parameters included the cytotoxicity indexes (lysosomal membrane stability, apoptotic enzymes caspase-3 and cathepsin D (CtD)), o xidative/reductive stress responses (superoxide dismutase (SOD) and catalase (CAT) activities, the levels of protein carbonyls (PC) and products of lipid peroxidation (TBARS), glutathione (GSH&GSSG), NAD+&NADH), metallothionein (total and Zn-bound) concentration, the biotransformation enzymes CYP450-dependent EROD, glutathione S-transferase (GST), and GTP-ase dynamin in the digestive gland with some inter-species differences in this spectrum. The applied spectrophotometric and chromatographic methods are described thoroughly in our previous work [6]. Results and Discussion. In the hepatocytes of rat, Cpz causes the biotransformation upregulation [7]. In our study, the activity of EROD increased both in M. galloprovincialis and U. tumidus, depending on the concentration and, particularly, in the Cpz II group of U. tumidus (by three times). This conversion of Cpz can result in the reactive metabolite formation [7]. According to this data, the inhibition or absence of the changes in the EROD activity in the Cpz I group of U. tumidus and Cpz II group of M. galloprovincialis can delay Cpz toxicity. On the other hand, the toxic product of biotransformation, quinoneimine is known to be eliminated by the GSH-dependent GST which activity was increased up to 63% in the Cpz I and II groups of marine mussels. Since in the freshwater mussels GST activity decreased in both exposures, the higher toxicity of Cpz was expected. Moreover, the GTP-ase dynamin activation in the Cpz I group of U. tumidus confirms the impact of this pharmaceutical on the clathrin-dependent endocytosis [8]. Conclusions. Summarizing, adverse outcome pathways related to the effect of Cpz on vertebrates in the μM concentration, were indicated in the mussels under the pM — nM concentrations with distinct inter-species concentration-related dependence, and the responses of stress were similar in both species. Particularly, marine molluscs can be a perspective model for evaluating Cpz adverse effects intrinsic for the higher vertebrates. [ABSTRACT FROM AUTHOR]

During the long-term operation, anti-aircraft missile weapons are characterized by the technical condition and level of reliability change influeincing the efficiency on the intended use. The article presents a model of surface-to-air missile system (SAMS) reliability during long-term operation, which contains a set of models, namely: a model of operation of ground combat assets (GCA) of SAMS according to the typical cyclogram of intended use (TCIU); a reliability dynamics model of SAMS GCA in the established system of maintenance and repair (SMR) and a reliability dynamics model of surface-to-air missiles (SAM) during extended usage. It is expedient to use the developed model at substantiation of requirements to the indicators of SAMS and SAM reliability for their development or modernization; when developing SAMS repair plans in terms of determining the time of SAMS GCA and (or) SAM repairing time and when developing methods for assessing the effectiveness of SAMS taking into account the duration of SAMS GCA and SAMS usage. [ABSTRACT FROM AUTHOR]

By using the Laguerre and Fourier integral transformations, we construct the solution of a plane quasistatic problem of thermoelasticity for a half strip with coating heated by a heat flow acting upon its ends and cooled through the surfaces of the coatings that are free of loads. The results of numerical analyses of the dependence of the thermal stressed state in a cermet on the rate of cooling and the relative thickness of the coating are presented. [ABSTRACT FROM AUTHOR]