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Using LA ICP MS dating of zircons, the age of the tuff (633±7 million years) of the Bolshoi Patom Formation at the base of the Vendian reference section in the south of the Siberian Platform (Ura Uplift) was estimated. The Vendian of the Siberian Platform was found to include the last Cryogenian (Marinoan) glaciation, and the postglacial sequence of the Vendian corresponds to the Ediacaran. In light of the obtained dating, the chronostratigraphy of the Riphean-Vendian deposits on the Ura Uplift and in adjacent areas is considered. The available geochronological and sequence stratigraphic data indicate the presence of hidden stratigraphic unconformity above the glacial horizon at the base of the Vendian, caused by glacio-isostasy.

This paper presents the results of developing a pulse analyzer for a borehole geophysical instrument intended for spectrometric gamma-ray logging. The module is implemented using a field-programmable gate array and enables real-time signal processing. An algorithm for converting biexponential responses of a scintillation detector into trapezoidal pulses is proposed. The efficiency of the implemented algorithm has been demonstrated in resolving pile-up pulses with a time delay of 300 ns. Using calibrated gamma-ray sources — Am‑241, Eu‑152, Cs‑137, Co‑60, and Th‑228 — the system's energy coverage in the range of 50 to 3000 keV is confirmed. The pulse analyzer features universal architecture and is compatible with various types of gamma-ray detectors.

The article presents the results of geochronological, geochemical and isotopic studies of intrusive complexes in the central and southern parts of Rudny Altai, which until recently have been practically uncharacterized using modern research methods. The results of U-Pb dating of zircon grains from igneous rocks (26 determinations) made it possible to establish 4 stages of endogenous activity: 1) Late Devonian (~ 370–360 Ma); 2) the end of the Early Carboniferous (~ 330–320 Ma); 3) Middle–Late Carboniferous (~ 315–305 Ma); 4) Early Permian (300–286 Ma). During each stage, both mafic and granitoid magmatism was manifested, which indicates the active development of mantle-crust interaction processes. An examination of the geochemical characteristics of the studied rocks allowed us to draw conclusions about the sources of magmas and the conditions of their melting, while comparison with geological and geochronological data from neighboring regions allowed us to determine the most likely geodynamic regimes for the manifestation of intrusive magmatism in the region. In the Late Devonian, magmatism occurred in a subduction setting on the active margin of the Siberian continent. At the end of the Early Carboniferous, magmatism was associated with the onset of orogenic processes during the formation of the Zaisan folded system orogenic structure. In the Middle to Late Carboniferous, magmatic activity reflects the onset of post-orogenic extension. Early Permian magmatism is due to a combination of post-orogenic extension and the activity of the Tarim large igneous province, formed as a result of the impact of the mantle plume of the same name on the lithosphere. Special attention is given to metallogenic aspects, and suggestions are made regarding the absence of ore deposits associated with intrusive magmatism in the region..

An automatic method is proposed for counting maize seedlings under conditions of substantial weed infestation and partial occlusion using ultra-high-resolution (<0.5 cm/pixel) RGB imagery acquired from an unmanned aerial vehicle. The method is based on a combination of computer vision and machine learning algorithms. Experimental results demonstrate that the accuracy of estimating the number of maize seedlings at early growth stages averaged 97%.

A histogram scene-based algorithm is developed to compensate for gain and bias non-uniformity in infrared focal-plane arrays. The statistical scene-based calibration method is proposed. Experimental results illustrating the effectiveness of the method are presented.

Issues related to the variational approach to the problem of non-parametric a priori uncertainty are disclosed is a method of converting a system of a priori stochastic differential equations, which enables to reduce the initial problem of nonlinear filtering of a multidimensional Markov process to a problem of filtering a new Markov process, characterised by a zero drift vector. The main provisions of the method of independent first integrals are given, allowing to provide the required transformation of linear systems of a priori stochastic differential equations. Filtering algorithms were constructed, in which the method of transforming multidimensional densities is used to restore the initial a priori and a posteriori densities of the probability distribution. An example of filtering the phase of a narrowband random process using the proposed conversion method is given. It has been shown that the proposed method of transformation using numerical integration reduces the requirements for the selection of parameters of the posterior density of the probability distribution of the vector of filtered parameters

Full Navier-Stokes equations are applied to identify two branches of viscous flow regimes in the form of steady traveling waves between two smooth surfaces. The existence domain of the new solutions is determined on the parameter plane (wavelength and Reynolds number), and the flow regimes corresponding to one of the branches are shown to be unstable. Stable regimes exist over a wide range of Reynolds numbers, starting from values significantly lower than the Reynolds number at which the linear stability of the base steady-state solution is lost. The main wave characteristics of the new-type solutions are calculated. Achieving these solutions requires a pressure drop substantially greater than that needed for the base steady-state solution, while also resulting in enhanced heat transfer from the walls.

A model for coupled axial-torsional oscillations of a drill string in a borehole of arbitrary profile is proposed. A numerical solution scheme is developed. A comparative analysis of the simulation results and field test data is performed. The main factors influencing the onset of stick-slip oscillations are identified as the intrinsic specific energy of rock destruction and the rotor speed. Comparison of the calculated results with field measurements demonstrates the adequacy of the model, with an accuracy acceptable for practical applications.

Results of an experimental study on the acoustoelasticity arising from the propagation of ultrasonic Rayleigh surface waves in a field of static bending stresses are presented. For a St. 20 steel specimen, the acoustoelastic effect is shown to differ under compression and tension. A calibration curve is constructed for Rayleigh surface waves, enabling their use for monitoring bending stresses-a capability not possible with bulk wave probing.

A gravity-based hydrodynamic flow loop capable of generating both steady and unsteady flow conditions is presented. The setup achieves velocities up to 16 cm/s and pressure fluctuations in a range of 60-130 mmHg within the measurement zone, enabling hemodynamic studies of virtually any segment of the cardiovascular system. For the first time, flow rate control is achieved by varying the angle at the junction of the systolic and diastolic flow circuits of the loop. Independent control of the minimum and maximum pressure in the unsteady flow is also implemented.