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A problem of control of trajectory motion of a quadrotor vehicle is considered. The choice of the form of required differential equations in the previously proposed method of tracking of a moving target is justified. The workability of the control system in the presence of measurement noise and external perturbations is confirmed by results of experiments with the AR.Drone quadrotor.

A structural technology of multicriterial optimization of control of technical objects with distributed parameters is proposed. The technology is based on a single-criterion version in the form of the minmax convolution of normalized performance criteria. The approach under development is based on the transition to an equivalent form of the variational problem with constraints, with the problem solution being a priori Pareto-effective. Further procedures of preliminary parametrization of control actions and subsequent reduction to a special problem of semi-infinite programming make it possible to find the sought extremals with the use of their Chebyshev properties and fundamental laws of the subject domain. An example of multicriterial optimization of operation modes of an engineering thermophysics object is presented, which is of independent interest.

The problem of asymptotic estimation of a linear combination of variables of the state of a bilinear dynamical system using a minimum-order observer is considered. An algorithm for calculating the matrix coefficients of a functional observer using the technology of canonization of matrices is proposed, and conditions for the solvability of the synthesis problem are formulated.

The authors analyze collecting capacity of desorbable species of xanthates. Desorbable species of a reagent are understood as the species capable to transfer from mineral particle to air bubble, i.e. to gas-liquid interface, at the moment of rupture of an interlayer between these interacting objects. Flotation process performance is evaluated at the presence of a mixed coating resulting from physical and chemical adsorption and in the presence of a chemosorption coating only. The rates of spreading products of interaction between butyl ethyl xanthates and lead nitrate over water surface are found. The spreading rates and collecting capacities of the mentioned reagents are correlated. It is found that an increase in the length of the hydrocarbon fragment increases collecting capacity of a reagent and the rate of spreading of its products over water surface.

In terms of sulfide copper-molybdenum ore of Sorsk stockwork deposit (Republic of Khakasia), the authors discuss the option of selective dissociation of minerals. The scope of the discussion embraces effect of pulsed-discharge treatment on particle-size indexes, structural and chemical properties and floatability of objects of the study. It is shown that the pulse-discharge treatment in a greater degree influences copper sulfides and levels their floatability while surface of molybdenite undergoes minor alteration. The pulse-discharge treatment allows enhancing flotation selectivity efficiency in separation of copper sulfides and molybdenite, and promotes removal of hydrophobic molybdenite film from quartz surface, which results in production of high-quality molybdenite concentrates.

Under analysis is on-site extractability of nonferrous and noble metals from tailings by leaching using natural reagents (humus acids, water, lignin). Redistribution of nonferrous and noble metals in percolation bed made of old tailings in the Norilsk copper-nickel ore field is studied. Kinetics of dissolving of nonferrous and noble metals under capillary ascensional percolation is investigated. It is shown that directional capillary percolation of solutions is applicable to extraction of nonferrous and noble metals from long-term storage mining waste.

When gold occurs in mining waste for a long time, it becomes coated with dense films of hydroxide of iron, manganese, copper and silver sulfides, hydromica powder and clayey particles, which greatly complicates concentration of such gold by gravity. An efficient method to remove such coatings from gold is treatment of waste using chemical reagents based on halogen-containing compounds. The article presents experimental results on extraction of fine gold from tailings of sluice boxes and dredging classifiers using such chemical reagents.

The undertaken research is aimed to reveal optimal physicochemical conditions for deep conversion of calcium-bearing alumosilicate raw material. An innovative technology of integrated extraction of nano-dispersion amorphous silica, alumina, calcium fluoride and other useful elements has been developed.

Under consideration is the influence of various crushing techniques on the particle-size distribution and selectivity of dissociation of basic mineral components in the composition of Dalnegorsk complex ore under pretreatment. Distribution of basic elements per size grades is determined in crushing feed and in products of magnetic separation and flotation. Conditions of preparation and separation of disintegration products are described. The authors illustrate the change in the dissociation selectivity criterion in jaw crushing and in disintegration in press to prepare different size ore for processing by magnetic separation and flotation.

In terms of Tashtagol Mine, the authors address the issues connected with the determination of surface shape in cavities formed by blasts of explosive charges in high-stress rock mass structured as a hierarchy of blocks. Laser scanning of a cavity offers the data on linear and angular characteristics of the cavity surface. The analysis of the surface structure provides details of the rock mass block hierarchy, which essentially influences formation of the roof and sidewalls of the cavity. Individual areas of the cavity surface are described with the help of approximation of measured coordinates of the cavity boundary in the cross sections using the second order curves, including circumferences and ellipses the radius of which are canonically connected with the phenomenon of zonal disintegration of rock mass.