Given an ensemble of datasets, we study the object classification accuracy in terms of the error probability depending on the amount of processed information using various fusion schemes. Schemes of combining weak discriminant functions in each dataset as well as in an ensemble of different modality datasets are suggested. For the proposed fusion schemes, the redundancy of the error probability relative to the information-theoretic lower bound defined by the modified rate-distortion function with the Hamming distortion measure is evaluated. The experimental evaluations in datasets of signature and face images show a decrease in the error probability and its redundancy with the amount of the processed information being increased by combining weak discriminant functions.
V.K. Abrosimov1, E.S. Michailova2
a:2:{s:4:"TEXT";s:146:"1Ministry of Defence of the Russian Federation, Moscow, Russia 2JSC NPO "Almaz" named after А.А.Raspletin, Moscow, Russia";s:4:"TYPE";s:4:"html";}
Keywords: group, swarm, control object, uncertainty, formation, model
The study deals with a conflict situation associated with the movement of clusters, including hundreds of small control objects in the field of responsibility of the radar station of an external observer. The task of the external observer is to monitor and trace the cluster movement and control it if a threatening situation occurs. The task of the cluster is to create the maximum possible uncertainty in decision making by the external observer. The cluster motion model is developed as K. Reynolds’ swarm behavior, supplemented by special coefficients. Three methods are developed for the formation of various cluster shapes, close to geometric and changing in the process of movement. A hypothesis is formulated and confirmed by mathematical modeling that, due to variations in the geometry, shape, and number of objects in a swarm cluster, there exist a possibility of creating situations where a swarm will be perceived by the external observer as a single large object different from the original one. It is shown that it is possible to create clusters simulating dangerous objects if the criterion for making a decision is the value of the effective scattering surface.
A.S. Ismagilova, N. D. Lushnikov
Ufa University of Science and Technology, Ufa, Russia
Keywords: information systems, neural networks, information protection, software system
This article describes features of automated implementation encryption of both biometric data and user information resources as a whole. The created mathematical model is based on an artificial neural network designed for encryption of biometric images in the account administrator folder using mathematical methods. The object of the study is the information systems of the PC. The subject of research is the tools of protection of user information using biometric multifactor authentication.
A.N. Zhdanova1, A.V. Kupriyanov1,2, A.A. Golova1, A.S. Bulgakov1, D.S. Bakanov1
a:2:{s:4:"TEXT";s:263:"1Samara National Research University, Samara, Russia 2Image Processing Systems Institute, Russian Academy of Sciences, Branch of the Federal State Research Center Crystallography and Photonics”, Russian Academy of Sciences, Samara, Russia";s:4:"TYPE";s:4:"html";}
Keywords: sentiment analysis, recurrent neural networks, data analysis, text tonality, prediction
The article is devoted to the application of machine learning methods for sentiment analysis of texts and to the study of the effectiveness of various architectures of neural networks. This direction is relevant in connection with the development of social networks and online recommendation services, where many users express their opinions about goods and services. The article presents the results of forecasting and comparing the structures of neural networks on real data from social networks. This allows determination of the most efficient architecture for the sentiment analysis of texts. The study may be useful for developers of social networks and recommendation services, as well as for researchers involved in natural language processing. The results can help improve the quality of the user opinion analysis and improve user satisfaction with services and products. Thus, the article contributes to the development of the field of machine learning and text data analysis.
S.E. Vorobeychikov, A.V. Pupkov
Tomsk State University, Tomsk, Russia
Keywords: autoregression, least squares estimator, sequential estimation, non-asymptotic confidence region
A non-asymptotic procedure for constructing the confidence region of the parameter of the Gaussian autoregression process of the p-th order with an unknown variance of the process noise is proposed. The confidence estimation procedure is based on the martingale property of the numerator of the deviation of the least squares estimator. The paper presents the results of numerical simulation.
E.Ya. Rapoport, Yu.E. Pleshivtseva, I.S. Levin
Samara State Technical University, Samara, Russia
Keywords: systems with distributed parameters, minimization of energy consumption, programmed control, alternance method, synthesis of optimal control
A method is proposed for synthesis of energy-efficient controllers in both open and closed domains of definition of spatiotemporal control actions for linear multidimensional objects of the parabolic type with distributed parameters under the conditions of a specified accuracy of uniform approximation of the system's final state to the required spatial distribution of the controlled variable. The suggested approach is based on the previously developed alternance method of constructing parameterized algorithms for optimal programmed control, which utilizes fundamental regularities of the subject area. It is shown that the sought controller equations are reduced to linear laws with constraints for feedbacks based on incomplete observation of the state of an object with non-stationary transfer coefficients, which are determined by a preliminary calculation of the programmed control action.
A.N. Zhirabok1,2, A.V. Zuev1,2, A.Ye. Shumsky1 1Far Eastern Federal University, Vladivostok, Russia 2Institute of Marine Technology Problems, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
Keywords: Nonlinear systems, disturbances, functional observer, model
The problem of functional observer design for dynamic systems described by nonlinear differential equations under external disturbances is considered. Relations that allow design of the observer of a reduced-order-dimensional invariant with respect to the disturbances and estimating the prescribed function of the state vector are derived. Theoretical results are illustrated by an example.
S.V. Rudometov, V.V. Okolnishnikov, S.S. Zhuravlev
Federal Research Center for Information and Computational Technologies, Novosibirsk, Russia
Keywords: distributed simulation, HLA, coal mine
The MTSS simulation system implements the possibility of distributed simulation. To implement this feature, the HLA standard is used. As an example of the use of distributed simulation, a federation consisting of two federates is presented: a simulation model of a coal mine working face and a simulation model of a coal mine conveyor network.
E.V. Antipina1, S.A. Mustafina1, A.F. Antipin2 1Ufa University of Science and Technology, Ufa, Russia 2Sterlitamak Branch of Ufa University of Science and Technology, Sterlitamak, Russia
Keywords: kinetic model of the reaction, optimal initial concentrations, differential evolution
The paper formulates a numerical algorithm for searching for optimal initial concentrations of substances in a catalytic reaction, which combines the principles of kinetic modeling and evolutionary calculations. The problem of optimal control of the catalytic reaction is formulated, where the control parameter is the vector of the initial concentrations of the initial substances. A step-by-step algorithm for solving the problem is described, which is based on the method of differential evolution. A computational experiment is carried out for the reaction of aminomethylation of thiols with the help of tetramethylmethanediamine. With the help of the above-described algorithm, the optimal concentrations of the initial substances are calculated, at which the highest value of the concentration of the reaction product is reached. It is shown that the calculated values of the initial concentrations of substances are consistent with the results of a chemical experiment.
P.E. Kotlyar
Institute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: radiation detectors, Golay cells, graphene membranes, tunnel transducers, cantilevers
Classical opto-acoustic receivers (OAR) are successfully used to solve a number of scientific and applied tasks, such as measuring weak optical radiation fluxes in the IR and THz ranges, quantitative and qualitative analysis of gas mixtures, and studies of absorption spectra of gases and vapors. The purpose, design, and evolution of the main structural elements of classical OAR are considered. The prospects of using single-layer graphene as the most promising material for creating membranes are analyzed. A significant increase in sensitivity is due to the exceptionally high elasticity of graphene combined with its high mechanical strength. It is shown that the use of a flexible membrane made of single-layer graphene reduces the OAR susceptibility to acoustic and vibration noise by more than three orders of magnitude without the use of any vibration protection devices. Due to the preservation of high elasticity by the graphene membrane at helium temperatures, the OAR operating range can be extended from 320 K to helium temperatures, which ensures reaching the theoretically maximum threshold sensitivity by reducing noise and opens up the possibility of wide application of the OAR for solving scientific problems of astrophysics and cosmology. Capacitive, optical, tunnel, and cantilever detectors of microdeformations of a flexible membrane are considered. It is shown that the maximum metrological characteristics of the OAR can be reached due to combining the unique capabilities of two developments: a membrane made of single-layer graphene and a tunnel microdeformation detector.
V.P. Lukin
V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk, Russia
Keywords: adaptive optics, turbulent atmosphere, active corrector mirror, Strehl parameter, hysteresis
This article is a logical continuation of the previous analysis of the dynamic characteristics of adaptive optics systems operating in a turbulent atmosphere, in particular, the influence of such an important factor of an active corrector mirror as its hysteresis is analyzed. An analytical approach is used to calculate the requirements to the dynamic parameters of the feedback loop of an adaptive system for focusing laser radiation through a turbulent atmosphere. The possibilities of using control algorithms in adaptive optics systems based on the description of their operation as a constant delay control system are considered. A corrector mirror model is used, which takes into account the time delay between the time of the signal and the time of its processing. To estimate the frequency of operation of the adaptive optics system, an analytical expression is used that relates the maximum achievable level of correction by the Strehl parameter with the most important system parameters: the accuracy and frequency of the wavefront sensor and the aperture size of the optical system, as well as with atmospheric parameters: the Fried parameter and the wind speed. The differences between two types of tracking loops are analyzed: open and closed loops in adaptive optics systems.
The results of numerical simulation of the irradiation by parasitic radiation of a cooled matrix photodetector in a cryostat with different shapes and designs of the cold diaphragm are presented. The optimal shape of the cold diaphragm is found to be a cylinder with two internal blends (additional diaphragms). The level of irradiation of the matrix photodetector with parasitic radiation is about 9.82×10-05 W/cm2 with an uneven distribution over the area of about 3%.
M.Yu. Malkina1, R.V. Balakin2,3 1Institute of Economics and Entrepreneurship, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia 2Institute of Economics and Entrepreneurship, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia, Nizhny Novgorod, Russia 3Financial Research Institute of the Ministry of Finance of the Russian Federation
Keywords: tax revenues, stress index, regions, federal districts, external shocks, sanctions, pandemic, decomposition
The study aims to examine the influence of external shocks, such as sanctions, the pandemic, and oil price fluctuations, on tax revenue stress in the country’s federal discticts and individual consistuent entities. To achieve this, we have developed a tax revenue stress index, which represents the spread from the moving standard deviation to the sliding rate of growth of annual tax revenues, and a methodology to decompose the index by its sources Using the developed index, we estimate tax revenue stress in Russian regions from January 2013 to October 2022, considering the pre-pandemic, pandemic, and recovery periods. Our findings indicate a significant positive correlation between tax revenue stress and oil price stress with a lag of 4-7 months, although the response of regions to oil market conditions varies. Notably, the Far Eastern, Ural, and Siberian federal districts experience higher average tax revenue stress. Among the federal districts, the Ural district plays a major role in both increasing and reducing tax revenue stress, while the Central district acts as a strong stress buffer during external shocks. The pandemic had a significant impact on tax revenues in most regions. However, in 24 out of 85 examined constitent entities of the Russian Federation, the average stress decreased, and in 36 regions, the maximum stress value decreased. During recovery, tax revenue stress was lower in 70 entities compared to the previous two periods. Nevertheless, metropolitan cities and certain regions have already felt the effects of new sanctions imposed in 2022. Notably, stress patterns behave abnormally in the Far Eastern border regions and Murmansk Oblast , which can be attributed to specific resilience factors related to their regional economies and specialization.
Based on the hypothesis of quasi-stationarity, relations were obtained for calculating the unsteady process of filling a vacuum vessel. As a criterion for the completion of the filling process, the admissible degree of pressure increase in the vacuum vessel is adopted. An analysis was made of the possibilities of increasing the duration of the filling process for a vacuum vessel of a given volume.
The density of liquid mixtures of lithium and potassium fluorides with a content of 51.2 and 71.1 mol % LiF was measured using gamma-ray attenuation technique in the temperature range from liquidus to 1000-1190 K. For a mixture of near-eutectic composition (51.2 mol % LiF), the relative density change during the solid-liquid phase transition and the density in the solid state near the melting point were directly determined for the first time. The concentration dependences of the molar volume and volumetric coefficient of thermal expansion for the LiF-KF liquid system were plotted on the basis of the experimental and literature data. The obtained dependences were found to be close to the concentration dependences of the corresponding volumetric properties for ideal solutions.
I.N. Ganiev1, R.S. Shonazarov2, A. Elmurod3, U.N. Faizulloev4, A.G. Safarov5
a:2:{s:4:"TYPE";s:4:"HTML";s:4:"TEXT";s:462:"1Institute of Chemistry named after V.I. Nikitin NAS of Tajikistan, Dushanbe, Tajikistan 2Bokhtar State University named after Nosir Khusrav, Bokhtar, Tajikistan 3Dangara State University, Dangara, Tajikistan 4National Research Technological University (NUST) “MISiS” in Dushanbe, Dushanbe, Tajikistan 5Physical-Technical Institute named after S.U. Umarov NAS of Tajikistan, Dushanbe, Tajikistan";}
Keywords: aluminum alloy AlCu4,5Mg1, calcium, “cooling” mode, heat capacity, enthalpy, entropy, Gibbs energy
The cooling rates of the studied alloy samples were determined in the "cooling" mode, by constructing thermograms of cooling alloys and their subsequent differentiation. Considering the heat capacity of the standard (Al brand A5N) and the cooling rates of the samples and the standard, the temperature dependence of the heat capacity of the aluminum alloy AlCu4,5Mg1 doped with calcium was calculated. Computer processing of the results served to obtain a polynomial of the temperature dependence of the heat capacity of alloys in the form of a four-term equation with the correlation coefficient R ≤ 0.999. It has been found that the heat capacity, enthalpy, and entropy of the alloys increase with increasing temperature, while the value of the Gibbs energy decreases. Additions of calcium in the range of 0.05 -1.0 wt. % reduce the heat capacity, heat transfer coefficient, enthalpy and entropy of the AlCu4,5Mg1 aluminum alloy, and the Gibbs energy has an inverse relationship.
S. Sabzpoushan1,2, M.R. Morad3 1University of Freiburg, Freiburg, Germany 2Sharif University of Technology 3Sharif University of Technology, Tehran, Iran
Keywords: solar-driven Brayton heat engine, cycle efficiency, regenerative cycle, radiative loss, heat transfer nonlinearity
In endoreversible cycles, irreversibility is considered only between the systems and their surroundings. In this paper, the modelling of heat interaction with a solar regenerative Brayton cycle is studied with regard to various fidelities based on the first and second laws of thermodynamics. The effect of linearity and nonlinearity related to the both convective and radiative heat interactions with the hot and cold reservoirs as well as radiation losses of the solar Brayton cycle have been studied, which is complementary to similar attempts for Carnot cycle. Total efficiencies are compared between various implemented models. The effect of temperature of six critical sections of the whole engine on the collector efficiency, cycle thermal efficiency and the system total efficiency has been studied. Besides, a comparison is done for a real example to show the importance of considering the nonlinearities for calculating thermal efficiency of a closed-loop Brayton cycle at different hot source temperatures, as well. These would help more efficient analysis of the emerging power cycles that can accelerate progress toward low-carbon power production.
The results of thermodynamic calculations and experimental studies on plasma processing of ash-and-slag waste and oil refinery waste with production of fuel gas and inert mineral material are presented. The calculated and experimental data on plasma-chemical processing of oil refinery waste are compared
On July 30, 2023, the famous scientist in the field of physical gas dynamics, dynamics of rarefied gases and thermal physics, Academician of the Russian Academy of Sciences, Professor Alexei K. Rebrov turned 90 years of age.
M. V. Kurlenya1, K. Kh. Lee2, V. G. Kazantsev3, U Li H.2, V. S. Zykov2 1Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Scientific Center VostNII, Kemerovo, Russia 3Federal Research and Production Center ALTAI, Biysk, Russia
Keywords: Modeling, coal, seam, gas drainage, flow, pressure in sorption, stress state
The apparatus of nonstationary thermoelasticity is used to estimate the joint and separate effects of gas pressure sorption and gravity on gas drainage and on stress state in the vicinity of underground openings. It is shown that gas flow changes the stress state of coal, and pressure in sorption essentially counteracts pressure in gravity. Ignorance of the latter fact may lead to a poorly substantiated choice of a coal gas drainage technology and to an erroneous prediction of rock strength and stability.
L. A. Nazarov1, N. A. Golikov1, A. A. Skulkin1, L. A. Nazarova2 1Novosibirsk State University, Novosibirsk, Russia 2Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Fractured porous rock mass, laboratory experiment, manmade geomaterial, regular layered sample, permeability, matrix, fractures, mass transfer coefficient, stress
The experimental procedure is developed and tested on a laboratory scale and using layered samples of manmade geomaterials. Within the dual-permeability model, the procedure enables determining parameters that govern fluid flow and poroelastic deformation in fractured porous rock masses, namely, fracture permeability k1 and mass transfer coefficient β, as well as their dependence on stresses σ. The testing procedure is proposed and implemented. In the procedure, under the stepwise increasing normal stress σ, the stationary flow rates Q1(σ) and Q2(σ) are measured in a quasiregular fractured porous sample at the preset pressure difference: using a standard setup (Q1) and in closed end-face fractures (Q2). The mathematical model of the experiment is constructed, and the analytical solution of the problem on stationary flow is obtained: pressure patterns in fractures, and stress-dependence of flow rates. The experimental data interpretation algorithm enables calculating k1 and β by the recorded flow rates Q1 and Q2. It is shown that the permeability k1 is proportional to σ -2, and β remains almost unchanged.
E. M. Gorbunova, S. M. Petukhova, A. G. Ivanov
Academician Sadovsky Institute of Geosphere Dynamics, Russian Academy of Sciences, Moscow, Russia
Keywords: Large-scale blast, iron ore deposit, Lebedinsky open pit mine, PPV, hydrogeological response
The authors analyze seismic and hydrogeological data recorded after a large-scale blast on 22 September 2021 in Lebedinsky open pit mine, Kursk Magnetic Anomaly. In blasting of four groups of blocks, the maximum values of PPV are determined at five observation points arranged at the epicentral distances of 1.7-4.9 km, as well as the amplitudes of the hydrogeological response are assessed in two observation wells in overlying rock mass. The main parameters of the blast-induced seismic effect are used to calculate maximum PPV from the earlier found relation. The divergence of the recorded and theoretical data is observed in the near field of the blast in the first group of blocks, at the reduced distances of 106-198 m/kg1/3. In blasting in sedimentary rocks at the reduced distances of 405-512 m/kg1/3, the difference in the wavefield is observed. The research findings can be used in drilling-and-blasting control.
Yu. F. Patrakov1, A. I. Stepanenko2, S. M. Nikitenko1, S. A. Semenova1, A. A. Stepanenko2 1Federal Research Center for Coal and Coal Chemistry, Siberian Branch, Russian Academy of Sciences, Kemerovo, Russia 2Gormashexport, Novosibirsk, Russia
Keywords: Grain size composition of coal, crushers, coal grindability, blended fuel
The article presents the results of toothed screw crushing of coal on a laboratory scale. The samples are the marketable coal from different deposits in Russia, Kazakhstan and Kyrgyzstan. From the analysis of change in the quantity outputs of grain sizes, it is found that irrespective of the coal field location and coal grade, the use of a toothed screw crusher in coal preparation for dressing leads to no overgrinding of coal.
V. I. Klishin1,2, A. N. Starodubov1,2, V. A. Kramarenko1, A. N. Kadochigova1, A. V. Kaplun1 1Federal Research Center for Coal and Coal Chemistry, Siberian Branch, Russian Academy of Sciences, Kemerovo, Russia 2Gorbachev Kuzbass State Technical University, Kemerovo, Russia
Keywords: Thick coal seams, underground mining, simulation model, powered roof support, feeder, outlet modes, scraper conveyor
The new design of a powered roof support for the controlled longwall top coal caving in thick coal seams contains a special outlet and a reciprocating feeder. The introduction of such technology needs pre-testing and analysis of the outlet modes per the support units, such that to ensure the maximum allowable fill of the longwall conveyor without its overloading and dynamic phenomena. Created in Rocky DEM environment with that end in view, the simulation model takes into account the physical effect of rock mass fracture using the discrete element method, and enables variation in the design parameters and operating conditions of the powered roof support. The implemented experiments make it possible to assess the interdependence of the average velocity of coal outlet to the conveyor, the outlet gate angle and the feeder vibration frequency.
V. V. Laptev, S. V. Lukichev
Mining Institute, Kola Science Center, Russian Academy of Sciences, Apatity, Russia
Keywords: Sublevel caving, design parameters, structural components, sublevel stoping, losses, dilution, ore recovery rates, discrete element method, numerical modeling, drawpoint shape
The article describes numerical modeling of sublevel stoping using the discrete element method. The study included development of a modeling procedure, creation and calibration of the numerical models, and the result analysis. The optimal design parameters of structural components of the mining system are found, which are promotive of reduced ore losses in sublevel stoping at the Khibiny apatite-nepheline deposits. Some behavioral patterns of rock mass during sublevel stoping are obtained. The mechanism of ore losses is described.
V. A. Babello1,2, M. V. Lizunkin2 1Chita Division-Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Chita, Russia 2Transbaikal State University, Chita, Russia
Keywords: Mineral deposit, tailings pond, dam, strong overburden dumps, bench tester, deformation characteristics, transport machine passability, stability, deformation modulus, plate-bearing test
Compressibility of disturbed-structure strong rocks is determined for predicting land subsidence and stability during operation of transport machines. The plate-bearing tests are carried out on a large bench tester at different normal pressures and different densities of strong overburden rocks. The method to estimate deformability of strong overburden rocks using a plate and a station rod is described. The results were used to assess passability of transport machines during damming and for the damp stability calculation.
L. A. Perez1, C. G. Perea2 1INCIMMET S.A. Development of New Services for the Excavation Solutions Area, Lima, Peru 2Group of Environmental Geochemistry, Pedagogical and Technological University of Colombia, Sogamoso, Colombia
Keywords: Sublevel stoping, cemented rock fill, backfill system, backfill strength, underground mining
The authors developed a pilot project to test different preparations of cemented rock fill, determine the appropriate mix design, and check necessary mix strength. The article presents the required resistance studies and the research method used to determine feasibility, cost performance and increased mine productivity and safety. The study achieved a resistance peak of 1.6 MPa, reduced dilution of the ore, and increased pillar stability.
L. V. Gorodilov, V. G. Kudryavtsev
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Hydraulic impactor, distribution pattern, throttle valving, impact frequency and energy, adaptive machine
The authors analyze the control circuit of the work process-related parameters of a hydraulic impactor with the piston retention before the back stroke phase. Retention is implemented via the throttle control of pressure in the hydraulic cell of the slide valve. The physical model of such hydraulic impactor is tested, and its energy characteristics are determined. The tests included re-tuning of throttles and slide homing spring, and variation in fluid flow rate. The article presents oscillograms of the hydraulic impactor dynamics and the slide performance versus throttle parameters, fluid flow rate and the spring pre-tension. The curves of the hydraulic impactor energy, retention pressure and fluid flow rate illustrate the energy adjustability using the proposed performance control circuit. The oscillograms of the slide motion during its work cycle are plotted, the features and shortages of the process are determined. The proposed design of the throttle valve provides the steady-state performance of hydraulic impactors.
Yu. M. Lekontsev1, P. V. Sazhin1, B. L. Gerike2, A. V. Novik3, Yu. B. Mezentsev4 1Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Federal Research Center for Coal and Coal Chemistry, Siberian Branch, Russian Academy of Sciences, Kemerovo, Russia 3Avtostroikomplekt LLC, Novosibirsk, Russia 4Industrial Metallurgical Holding-Coal, Kemerovo, Russia
Keywords: Multiplier, hydraulic fracturing, distribution, cylinder, throttle, valve
The authors discuss the issue of engineering a special gear to change the power fluid pressure in hydraulic fracturing of strong rocks. The article describes the operation of the gear on the basis of implemented laboratory tests, and proposes the ways of eliminating deficiencies. The size and shape of choke grooves for the careful switching of the control valve subject to the power fluid flow rate are determined. The hydraulic circuit of the jet-control slide-type valve is developed. It allows improved accuracy and precision of the valve switching.
M. A. Semin, S. A. Bublik
Mining Institute, Ural Branch, Russian Academy of Sciences, Perm, Russia
Keywords: Artificial ground freezing, salina, pore water salinity, eutectic point, hidden crystallization heat, numerical modeling
The influence of phase transitions in moist and salt-containing soil on freezing process is analyzed. The effects connected with the crystallization heat of pore water under negative temperatures and with the crystallization heat of salt when the eutectic point is reached are discussed. The conclusions on reachability of the eutectic point in artificially frozen strata above saline are drawn. Using a mathematical mode of heat processes in artificially frozen clay containing the common salt solution, the influence of the offset of the eutectic point on the temperature field in the frozen ground is analyzed.
V. A. Chanturia, I. Zh. Bunin, M. V. Ryazantseva
Academician Melnikov Institute of Comprehensive Development of Mineral Resources-IPKON, Russian Academy of Sciences, Moscow, Russia
Keywords: Pyrite, arsenopyrite, low-temperature plasma, dielectric barrier discharge, surface, acid-base properties, adsorption, flotation
The authors describe the integrated studies into the influence exerted by nonequilibrium low-temperature plasma of dielectric barrier discharge in air under normal conditions and pressure on the acid-base, adsorption and flotation properties of natural iron sulfides (pyrite and arsenopyrite). The studies aimed to correlate the plasmachemical treatment parameters with the physicochemical and process properties of sulfide minerals. Using the Hammet indicator method, it is found that plasma treatment strengthens acceptor properties and weakens electron donor properties of pyrite surface, as well as weakens acceptor properties of arsenopyrite. Adsorptive properties of pyrite relative to the electron-donor butyl xanthate grow, and, as a consequence, flotation activity of the mineral improves. In case of arsenopyrite, the adsorptive properties and flotation activity decrease. It is shown that the low-temperature plasma pretreatment of minerals reduces arsenic yield in flotation froth by 10-11% at the reduced arsenic content of concentrate by 0.71-0.78%.
a:2:{s:4:"TEXT";s:33:"S. A. Kondrat’ev, I. A. Konovalov";s:4:"TYPE";s:4:"text";}
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Flotation, galena, physisorbed collector, lead xanthate, pH, collector spreading velocity
The authors propose the galena flotation mechanism based on the joint work of chemisorbed collector and physisorbed lead xanthate in molecular form. It is proved experimentally that the products of interaction between xanthate and lead ions possess surface activity dependent on the concentration ratio and on solution pH. In alkaline range, they spread over the gas-water interface and can remove water from the interlayer between a mineral particle and a gas bubble. In sub-acid medium and at the increased mole ratio of lead ions to xanthate anions, the spreading velocity of the interaction products decreases. The physisorption mechanism of the collector has disclosed the causes of high floatability of galena in the alkaline range of pH and the decreased floatability in the sub-acid domain.
a:2:{s:4:"TEXT";s:16:"S. A. Kondrat’ev";s:4:"TYPE";s:4:"text";}
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Flotation, collector physisorption, flotation activity criterion
The causes of coincidence between pH of a solution of collectors, at which the maximal recovery of a target component is reached, and pH of the solution with minimal surface tension are discussed. Based on the physisorption mechanism of a collector, the floatability connection with the surface tension of the solution is explained. It is shown that extraction of ion-molecular associates from the solution and the presumptive increase in the mineral surface hydrophobicity are not an explanation of the increased recovery. The floatability improvement is achieved via removal of the kinetic constraint of the flotation contact by surface-active species of collectors. The increase in the collecting activity of a blend of collectors is explained by the synergetic effect of the decreased surface tension and reduced induction time. The criterion of flotation activity of a physisorbable collector is proposed.
A. A. Lavrinenko, P. A. Sysa
Academician Melnikov Institute of Comprehensive Development of Mineral Resources-IPKON, Russian Academy of Sciences, Moscow, Russia
Keywords: Magnetic hydrocyclone, separation selectivity, magnetic fraction, iron ore processing, magnetic force, centrifugal force, iron content
A new device designed for wet magnetic separation-magnetic hydrocyclone-allows separating magnetic fraction from a fast and curved flow of pulp. The advantages of the magnetic hydrocyclone are the high specific output and the design simplicity which governs reliability of the device. The pattern of calculation of the magnetic hydrocyclonage performance represents an estimation of separability of magnetic fraction depending on the device geometry, variation in the magnetic field parameters, flow velocity and the physical parameters of the particles. The processing performance from calculations is compared with the results of the magnetic hydrocyclone testing. The proposed device is recommended to be included in the processing flow chart for ferruginous quartzite and other types of ore with the pronounced magnetic properties. Inclusion a magnetic system allowing higher magnetic induction up to 5-10 Tl in the flow chart makes it possible to extract weakly magnetic minerals.
A. G. Mikhailov, I. I. Vashlaev, E. N. Merkulova, N. F. Usmanova, A. E. Zuev
Institute of Chemistry and Chemical Technology, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia
Keywords: Filtration, geochemical phase composition, water solution, fluid
The article describes the experiment on the upward percolating mass transfer by water solution according to the natural mechanism of movement of solutions toward ground surface with water evaporation in atmosphere. Useful components settle out from the solutions and concentrate on the evaporation barrier. The experiment simulates a complete cycle of processes for flotation tailings of complex ore: feed of solutions in boreholes from surface to bottom of a tailings body; spreading of the solutions in the tailings body; capillary ascent to the surface; settling out and concentration of useful salts on the evaporation barrier. The usability of this approach and some parameters of the mass transfer process can be found from the relevant research.
A. I. Matveev, V. R. Vinokurov
Chersky Institute of Mining of the North, Siberian Branch, Russian Academy of Sciences, Yakutsk, Russia
Keywords: Fracture, breaking machine, operative parts, hardness, particles, grain size composition, efficiency
Using a laboratory model of a vertical centrifugal breaking machine, the milling efficiency of ore having different Mohs hardnesses is found. The rational structural and operating parameters of the breaking machine are determined for such ore materials. The data are included in the project documentation development for manufacturing a pilot vertical centrifugal breaking machine VTSI-12.
T. N. Matveeva, V. A. Minaev, N. K. Gromova
Academician Melnikov Institute of Comprehensive Development of Mineral Resources-IPKON, Russian Academy of Sciences, Moscow, Russia
Keywords: Sulfide minerals, optical / electron / laser microscopy, morpholine dithiocarbamate, hogweed extract
The optical, electron scanning and laser microscopy methods produced new experimental data on the adsorption layer generated by the chelating agent MDTC and hogweed extract on the surface of sulfide minerals in composition of complex ore. It is found that MDTC selectively attaches to chalcopyrite and forms a stable and water-insoluble compound with copper, which uniformly covers the whole surface of the mineral. It is determined for the first time that at the surface of pyrite, intense formation of dark-brown crystals of MDTC oxidation products takes place-dimorpholinethiuram disulfide which is chemically adsorbed at the mineral and is resistant to multiple washing-off in water. Morpholine dithiocarbamate does not interact with the surface of arsenopyrite and scheelite, and does not form stable phases with the components of these minerals. Hogweed extract does not desorb MDTC and is observed on the pre-adsorbed collector in the form of a fine bluish film washable off with water. At arsenopyrite and scheelite, a few separate and fine spots of hogweed are found.
Luo Da-Wei, Bai Jun-Zhe, Zhang Yu, Wu Di
Chengdu University of Technology, Chengdu, China
Keywords: Mineral purification, quartz, flotation, flotation collector
This paper studies the effect of using cationic/mixed anionic collectors in the practical application of quartz sand flotation. The combined use of Dodecylamine(DDA)/sodium oleate(NaOL)/sodium dodecyl sulfonate(SDS) is the innovative point of this paper. This experiment used quartz sand from Hanzhong, Shaanxi Province, China. The results showed that the combined use of DDA, NaOL and SDS was better than the single use. Using DDA/NaOL/SDS mixed collector, the removal efficiency of Al2O3 can reach 75.1%, compared with DDA/NaOL mixed collector, the purification effect of Al2O3 can be increased by 11.1%. Compared with DDA/SDS mixed collector, the use of this mixed collector can greatly improve the purification effect and recovery rate. And the quartz concentrate has a good recovery rate in practical application.
K. K. Razmakhnin1,2, I. S. Kuroshev2, I. B. Razmakhnina1 1Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Chita, Russia 2Environmental Industrial Policy Center, Moscow, Russia
Keywords: Coal, Apsat deposit, pretreatment, thermal modification, carbonization, hydrochemical modification, gas-steam activation, alkali, adsorption capacity, application prospects
A brief description of coal resources in Transbaikalia is given. The issues of thermal and hydrochemical modification of coal from Apsat deposit are discussed. The usability of carbonization, gas-steam activation and alkaline treatment of low-caking coal for the improvement of coal adsorption capacity is determined. The proposed technology of Apsat coal preparation and dressing includes crushing, screening, carbonization and steam activation. The characteristics of the initial and treated coal are presented. The main physicochemical properties of the produced carbon adsorbents are determined. The coal modification parameters are identified. The computer-aided modeling of activated carbon adsorbents based on the quantum-chemical interaction of particles is described. The application areas of high-quality adsorbents in mining waste treatment are specified.
Li Hu1, Zheng Jie1, Xue Lian2,3,4, Zhao Xue1, Lei Xiuqiang1, Gong Xue1 1Sichuan Institute of Geological Engineering Investigation Group Co., Ltd, Chengdu, China 2Chengdu Center of China Geological Survey, Chengdu, China 3Technology Innovation Center for Risk Prevention and Mitigation of Geohazard, Ministry of Natural Resources, Chengdu, China 4Observation and Research Station of Chengdu Geological Hazards, Ministry of Natural Resources, Chengdu, China
Keywords: InSAR, Probabilistic Integration Method, Genetic Algorithm, insufficient mining, parameter inversion
By combining the advantages of InSAR, Probabilistic Integral Method and Genetic Algorithm, an improved method for dynamic prediction of probability integral parameters is proposed to realize subsidence inversion and prediction in insufficient mining. Firstly, InSAR is used to obtain the time series information of surface deformation in goaf. Then, a genetic algorithm-based parameter inversion model is constructed to invert the subsidence parameters such as subsidence coefficient and influence radius. After that, a dynamic prediction function is established to obtain the complete surface subsidence pattern and dynamic change trend of the mining area. Taking a goaf in Shanxi Province as the experimental object, Sentinel-1A(S-1A) image as the data source, combined with PIM and InSAR data, the parameter inversion model is used to successfully obtain the dynamic change process of mining subsidence parameters. The results show that the dynamic prediction function can achieve a certain effect on surface prediction in insufficient mining, and the parameter inversion model based on genetic algorithm has a high inversion accuracy, which provides a basis for surface prediction in insufficient mining.
