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For correct numerical interpretation of the results of tomographic experiment, i.e. estimates of objects attenuation coefficients it is important to obtain reconstruction of high quality which depends directly on the methods of processing experimental data. Data processing flow begins with its preparation for the application of the reconstruction algorithm. The necessary part of data processing contains the subtraction of the black field, normalization considering empty data, and taking logarithm. This part is not sufficient for obtaining high-quality reconstruction when working with real data since it is not ideal. Real data include noise and distortions due to changes of the set-up geometrical parameters during the experiment. We have analyzed two possible types of data corruptions during experiment and suggested corrections for them. The first correction is applied to change thermal shifts regarding beam decentralization, and the second accounts for and eliminates the effect of the polychromatic nature of the radiation on the results of tomographic reconstruction. These methods were tested with both real and synthetic data. Both synthetic and real experiments show that suggested methods improve the reconstruction quality. In real experiments, the level of agreement between automatic parameter adjustment and experts is about 90%.

An intensely developing aspect of advanced microelectronics is microelectromechanical systems (MEMS). The present paper describes various issues associated with the development of a new MEMS generator of clock frequency capable of operating at gigahertz frequencies. The main features of generating and supporting forced oscillations of the moving electrode under the action of electrostatic forces are analyzed. A possibility of supporting such oscillations under conditions of high inertial g-loads (up to 10⁶g and more) is demonstrated. A mathematical model of a micro-oscillator is developed, and the basic regimes of its operation are described.

A possibility of using the autocollimation and interference methods for real-time nonintrusive control of the surface shapes of photodetectors that are sensitive in the infrared range and are fabricated by the flip-chip technology is considered. These methods allow monitoring the surface shapes and the maximum deflections. These methods are applied in the present study to measure the surface shapes of fragments of silicone instrumental boards and arrays of photosensitive elements on GaAs substrates, as well as the surface shapes of photodetectors at different stages of fracture and in the course of thermal cycling.

A combined method of object visualization based on analytical and scalar perturbation functions and three-dimensional textures with the use of graphics processing units is proposed. To display the terrain and the change in levels of detail, the same method as that for color textures is applied, and vertex shaders are used in the case of scattered light. A method of real-time visualization of three-dimensional clouds is described. For this purpose, it is proposed to form three-dimensional textures by means of pre-processing of the cloud structure and volume-oriented visualization.

Modern methods of visual navigation for mobile robots are considered. A hierarchical representation structure of the surrounding space corresponding to the hierarchical organization of the mobile robot control system is proposed. Modern approaches to building cartographic models are presented. Their development will bring the navigation system closer to that created by the human intellect and combines vision and a semantic view of the world within cognitive maps.

The problem of automatic verification of control algorithms developed by tools of process-oriented programming for cyberphysical systems is solved. A method based on software simulators of the control object is proposed, and its implementation on the basis of the LabVIEW package and Reflex language translator is described.

Adaptation of the process-oriented approach to programming of microcontrollers in embedded systems is described. Specific features of control algorithms and programming of microcontrollers are analyzed. A mathematical model of the control algorithm, which implies a mechanism of the description of microcontroller interruptions in the form of hyperprocesses, is proposed, and its dynamic semantics is provided. The model proposed in the study is a conceptual framework for the development of specialized languages of process-oriented programming of embedded systems.

A machine learning approach for prediction the characteristics of tonal noise formed in a foil flow is tested. Experimental data are used to construct and analyze the mathematical models of pressure amplitude regression and models of classification of regimes of high-level tonal noise coming from the dimensionless parameters of the flow. Different families of algorithms are considered: from linear models to artificial neural networks. It is shown that a gradient boosting model with a determination coefficient 95 % is the most accurate for describing and predicting the spectral curves of acoustic pressure on the entire interval of values of amplitudes and characteristic frequencies.

The article summarizes the results of the studies performed at the Institute of Chemistry and Chemical Technology SB RAS from 1998 to 2014 in the area of thermocatalytic transformations of brown and sapropelite coal into gaseous and liquid fuels, binding and carbon materials. The fundamentals were developed for the autothermal process of brown coal carbonisation in a fluidized bed of catalyst with obtaining semi-coke and carbon sorbents. Additionally, the simultaneous preparation of fuel gas and syngas based on parallel operation of two fluidized bed reactors that are pyrolyser and gasifier was studied. Due to the use of a fluidized bed of catalyst particles during oxidative carbonization of brown coal, we managed to combine in one apparatus the processes of combustion and thermal treatment of coal. Metallurgical slags capable of oxidizing volatile substances released from coal were used as catalysts at elevated temperatures. The developed method allowed regulating the degree of coal carbonisation and, respectively, the properties of the resulting carbon products by changing the consumption coefficients of powdery coal and air fed to the reactor. Herewith, the depth of thermal treatment of coal and such characteristics of the resulting carbon product, as the heat of combustion, a content of volatile substances, its chemical composition and porosity were changed. Only the most reactive part of fuels was gasified in a catalytic boiling layer in a mode of partial gasification of coal and the porous carbon product was formed, the latter could be used as a sorbent. It was proposed to produce syngas by using a pyrolyser-gasifier. Semi-coke formed during brown coal carbonisation in a pyrolyser was raw materials for steam gasification. Since the major part of volatile substances was already removed from semi-coke, the release of resinous products did not accompany its gasification. Therefore, the product gas did not require expensive purification from impurities before its use in synthesis processes. New methods for the preparation of liquid fuels and road binders were proposed. They were based on the process of hydrogenation of brown coal and its mixtures with oil residues and synthetic polymers in the presence of mechanically activated iron-ore catalysts in the environment of hydrogen donor solvents. Products of joint refining of brown coal, oil residues and synthetic polymers wastes were used to obtain road binders, and it was proposed to obtain modifiers for paving asphalt based on oil-resistant rubbers and liquid coal products. The optimum conditions for thermal refining of sapropelite coal in a reactor with a fluidized bed were selected. They provided the increased yield of liquid products in comparison with the known processes of semicoking of coal. The composition of the products allowed their refining by standard oil refining technologies.

The optimum conditions for the synthesis of enterosorbents of birch bark bast were determined by experimental and calculation methods. The regression equations describing the dependence of characteristics of enterosorbents from conditions of its synthesis were obtained. The optimum conditions for the preparation of an enterosorbent with the maximum sorption activity for methylene blue and containing less than 5 mass % of water soluble substances were calculated using these equations: NaOH concentration of 1.5 mass %, a temperature of 80 °C and treatment duration of 60 min. Calculated values correlate well with experimentally obtained results.