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According to GPS monitoring, recent tectonic process between Tarim and West Siberia in the band within 80-95ºE is generated by the northward movement of the Tarim block. During the accompanying horizontal compression of the area, orogeny takes place within linear mobile zones when blocks are squeezed into the upper half-space. When the orientation of the mobile zones is transverse to the compression direction, the leading orogenic process is the formation of reverse faults. When these directions intersect at an acute angle, the principal features of the mountain relief are formed by oblique-slip and strike-slip faults. The spatial distribution of seismic activity A ₁₀ over a 40-year period of instrumental observations within the mobile zones of the study area is extremely nonuniform. Seismic activity increases to the south, toward the source of deformations - the Indo-Eurasian collision. The maximum activity is observed at the reverse-fault boundaries of the eastern Tien Shan (~40). The seismic activity of the strike-slip fault boundaries of the Great Altai is considerably lower (~0.11-0.16).

Lenses of water-saturated unfrozen rocks (taliks) in permafrost are important sources of freshwater in high-latitude regions. Taliks stand out against the host frozen rocks in much lower resistivity and thus are detectable by resistivity surveys. TEM soundings are especially efficient in this application as they can go without galvanic grounding, have small offsets, and are sensitive to buried conductors. Early-time TEM data in the Taz area of the Yamal-Nenets district bear strong effects of fast-decaying inductively induced polarization (IIP), which rules out the use of nonpolarizable earth assumption for their interpretation. The TEM responses are inverted by means of the TEM-IP software using the model of a polarizable earth with Cole-Cole complex frequency-dependent conductivity. The resulting earth model mainly includes three layers, with a 100 to 250 m thick highly resistive polarizable upper layer. The polarization parameters of the layer (chargeability, time constant and exponent) are typical of frozen sedimentary rocks, while the presence of a talik reduces notably the effective resistivity and chargeability. This feature can be used as a guide to taliks, as it was confirmed by TEM surveys and subsequent drilling.

The composition, structure, and properties of different genetic types of serpentinites developed after ultrabasic rocks are studied. The rocks were sampled from massifs located along the Main Ural Fault, in a Paleozoic subduction zone. We consider specific features of serpentinites developed after chromite-bearing ultrabasic rocks, in metamorphic zones of carbonate rocks, and within the zone of weathering of ultrabasic rocks. A comparative study of the microstructure and chemical and phase compositions of serpentinites is carried out by IR spectroscopy, scanning electron microscopy, and thermal, X-ray diffraction, and microprobe analyses. The petrophysical properties and acoustic emission of the rocks are examined. Several genetic and structural groups of serpentinites developed after different protoliths (mantle and crustal) in different geologic conditions are recognized.

Based on analysis of geothermal data from the Ural superdeep borehole (SG-4) and Onega parametric borehole, the first reconstructions of the ground surface heat flux changes for the last 40 kyr have been made. The increase in heat flux during the Pleistocene-Holocene warming (20-10 ka) proceeded ~2 kyr earlier than the growth in the surface temperature; reaching the maximum value of 0.08-0.13 W/m2 at ~13 ka, the heat flux was reduced. The coordinated changes in heat flux and average annual insolation at 60º N at 5-24 ka indicate that the orbital factors were the main cause of climatic changes in this period. The correlations between the changes in heat flux and CO2 content in the Antarctic ice cores with temperature changes are analyzed.

This work is devoted to a possible way to construct time-optimal closed systems for incompletely determined linear models of distributed-parameter control plants of parabolic type, which provides real-time identification of their parametric characteristics according to the results of monitoring the state of the plants. The structural-parametric synthesis of the proposed controllers is based on the alternance method of designing optimal software controls. The paper gives an example (of independent interest) of constructing a time-optimal system for the control of the process of induction heating under typical conditions of interval uncertainty of the initial temperature and heat losses.

This work is devoted to the technique of solving the problem of structural-parametric synthesis of typical controllers in a multiloop cascade automatic control system, which is developed on the basis of the alternance method of parametric optimization that provides the maximum degree of invariance of local control loops relative to external perturbations with given limitations on the peak of amplitude-frequency characteristics of closed loops of the synthesized automatic control system. The task of optimizing the subsystem for controlling the fuel oil temperature in a multiloop control system of primary oil refining on an atmospheric and vacuum crude distillation unit is considered as an example, which is of independent interest.

It is shown that the problem of estimating unmeasurable external perturbations from a mathematical point of view is equivalent to estimating some of the state variables of an extended plant. An algorithm for estimating unmeasurable external perturbations using a functional observer is proposed, and conditions for the solvability of the synthesis problem are formulated. The resulting solution is obtained using the method of matrix canonization.

The problem of control of the aircraft attitude in a three-dimensional space is considered. The attitude is described by the Euler angles between the axes of the body-fixed coordinate system and the Earth frame. A method of calculating the torque driving the aircraft to a prescribed attitude is proposed. A controller implementing this method is presented. Results of simulations are reported.

A method of synthesis of a self-adjusting multichannel system with a reference model for centralized control of autonomous underwater vehicle motion is developed. Conditions of selfadjustment process stability with allowance for dynamic reciprocal effects and kinematic relations between all control channels in the presence of parametric nonstationarity of the complete nonlinear mathematical model of the vehicle are obtained. The amplitude of the self-adjustment signal is formed as a function of coordinates and reference-input signals in order to reduce the control signal magnitude. The developed system ensures a high quality of control of an underwater vehicle with significant variations of its parameters.

A possible approach to the calculation of standard controller parameters based on the localization method is considered. It is shown that the controllers designed in this way completely solve the problem of stabilization of first- and second-order nonlinear nonstationary plants. Variants of implementation of standard controllers and recommendations for calculating their parameters are presented and the properties of the obtained automatic systems are investigated. It is noted that a general characteristic feature of systems with the proposed PID controller is the occurrence of fast motion components against the background of slow work processes. Results of numerical modeling illustrate the main properties of the systems considered.