Home – Home – Jornals – REPORTS OF RUSSIAN HIGHER EDUCATION ACADEMY OF SCIENCES 2013 number

We study the problem of integral geometry in a strip on a family of curves of spherical type with a given weight function. We prove a uniqueness theorem and obtain an explicit expression for the Fourier transform of the solution of considered problem of integral geometry in a class of smooth finite functions.

In the present article, the application of calculus of variations was based to investigate nano-objects properties. The equations for the order parameter calculations were obtained in the case of supported thin films. The order parameter calculations were carried out for the coherent thin film-support boundary. The cases when the substances of thin film and support have the second-order phase transition were considered. The comparison of coherent, semi-coherent, and non-coherent boundaries was performed.

A numerical method for solving general problem of optimal complete set related to the class of NP-hard problems of discrete programming with Boolean variables has been proposed. The method is based on procedures of linearization of the initial conditions, Lagrangian decomposition and iterative parametric analysis of sequences generated subproblems. It has been shown that the algorithm is effective and asymptotically accurate according to dimension of optimal complete set problems.

VEPP-4M is an electron-positron collider operating in the wide beam energy range from 0.9 GeV to 5.5 GeV. Since 2002 experiments on HEP are conducted at the collider with detector KEDR. Besides HEP, there are other scientific programs at the VEPP-4 accelerator complex including SR experiments, nuclear physics studies with internal gas target, CPT-theorem verification, accelerator physics experiments, etc. The paper discusses the recent results, present status and prospective plans of the facility.

The beam of negative hydrogen ions is injected into the tandem accelerator with vacuum insulation in order to obtain high-current proton beam. To accurately direct the beam into the accelerator the magnetic focusing lenses are used. In this paper it is described the design of the special beam detector mounted in front of the first accelerating electrode and intended to measure beam profile and the current density. The results of measurements of the dependence of the current density on the power of the magnetic focusing lenses are shown. The parameters of the beam resulting in the best agreement of calculation and experiment are specified. The optimum focusing mode to inject the negative hydrogen ions into the accelerator is determined.

In the Institute of Nuclear Physics SB RAS the epithermal neutron source is entered into operation based on the tandem – accelerator with vacuum isolation. There was evaluated the accelerating installation components of a x-ray field causing dark current and breakdowns in accelerating gaps. The experimental measurements were carried out and the study results of the doze capacity dynamics are submitted, depending on change of a dark current in tandem accelerating gaps. The design changes of installation for prevention of occurrence of powerful X-ray radiation are offered and realized. The carried research allows setting necessary parameters for designing medical installation on the basis of an accelerator-tandem with vacuum isolation with the purpose of realization in oncological clinics neutron-capture therapy of malignant tumors.

Mathematical modeling of the shoulder rod deflection under longitudinal impact upon a rigid obstacle is carried out. A brief derivation of the formula for calculation of the rod bending in case of eccentrical impact forces is given. The value of the critical compression load is calculated by Tymoshenko method. The rod deflection value with the eccentricity of the longitudinal load depending on the size of the initial speed is calculated.

Algorithm for rejection of out-of-band interference is proposed. The algorithm is based on formation of invariant statistics. These statistics are invariant to a group of additive transformations characterizing a priori uncertainty of the interference’s frequency. The rejection is implemented by subtracting a projection of an observed spectrum into an interference subspace. The performance of the algorithm is summarized.

The method of the rigid gear's teeth profiling for harmonic drive is presented. The standard roller chain is used as the flexible gear. The method worked out is based on the piecewise-arc approximation of the flexible gear deformation by the spatial motion of the axis of the chain's joint. The method allows to design harmonic chain drives with high output capability and reliability.

Method for solving systems of finite element equations arising in vector finite element method with field separation technique for modeling a three dimensional electromagnetic field induced by horizontal electrical line in marine medium is considered. The advantage of developed approach to solving finite element systems of linear algebraic equations arising in marine electrical survey is shown.

The problem of the absorbed dose distribution during the EB treatment by ELV accelerator is considered. The value of the absorbed dose is determined by the speed of scanning electron beam along the accelerator exit window (i.e. the movement across the conveyor). It is determined both by the shape of scanning current and by the geometry of scanning magnets. A simple way to improve the dose distribution near the edges of the extraction device of accelerator is suggested. It allows to provide the non-uniformity less 4 %.

Thermodynamically coupled dehydrogenation of ethane in a membrane reactor is studied by mathematical modeling. The dehydrogenation of ethane in a membrane reactor with additional combustion of hydrogen is shown to have an advantage over dehydrogenation in a tubular reactor. Verification of the mathematical model of the process is performed.

The complete system of hydrodynamic equations describing the development of instability of the reaction front in the hydrodynamic approximation is reduced to a closed system of surface equations with the use of Lagrange variables, integrals of motion, and their analogs. In the adiabatic approximation, it is shown how to take into account the acoustic vibrations of the gas density caused by this motion.

The problem of flame propagation is studied as an example of unstable fronts that wrinkle on many scales. The analytic tool of pole expansion in the complex plane is employed to address the interaction of the unstable growth process with random initial conditions and perturbations. We argue that the effect of random noise is immense and that it can never be neglected in sufficiently large systems. We present simulations that lead to scaling laws for the velocity and acceleration of the front as a function of the system size and the level of noise and also analytic arguments that explain these results in terms of the noisy pole dynamics.

Problems of decreasing the flame speed resulting from pre-mixed gas explosions and attenuating explosion overpressures are discussed. A cylindrical test pipeline with an 89 × 4.5 mm cross section is used to study flame propagation characteristics of an acetylene–air mixture both in the empty pipeline and in the presence of aluminum silicate wool attached to the internal wall of the pipeline. Experimental results show that aluminum silicate wool, which is a kind of a fibroid porous material with a high specific surface area, decreases the increment of the outlet flame speed and attenuates drastically the explosion overpressure if the length of the porous insert exceeds the critical length.

An accumulated combustible dust layer on some hot process equipment, such as grinders, dryers, hot bearings, etc., can be ignited and lead to fires if the hot surface temperature is sufficiently high. Experimental tests are used to determine the minimum hot surface temperature for dust ignition, the ignition temperature of dust itself, and the ignition times in this study. Egyptian rice husk dust is sieved into different sizes (particle diameters) to be used in this investigation. The effects of the dust particle size and the sample size (depth of the dust layer) on ignition parameters are tested. The boundary between the ignition and non-ignition conditions is investigated precisely through a large number of tests. The results show that the minimum hot plate temperature for ignition of dusts decreases as the dust layer depth increases.

The so-called gradient relations, i.e., analytical formulas that define the relationship between partial spatial derivatives (gradients) of pressure, density, and gas particle velocity behind a plane detonation front and the acceleration of the front, are obtained within the framework of a model based on the assumption of isothermality of gas detonation products. It is shown that the relations can be used to simplify the description of overdriven detonation regimes in chemically reacting gas.

This paper reports on an investigation of detonation initiation with a transversal flame jet. Series of single-cycle experiments are performed, where stoichiometric propane–oxygen mixtures with nitrogen dilution at atmospheric initial pressure are used, both in the flame sub-chamber with varying configurations and in the test tube 70 mm in diameter and 1550 mm long. The experimental results show that the flame jet orifice diameter slightly affects the detonation initiation sensitivity, and the flame sub-chamber configurations exert a minor effect on the deflagration-to-detonation transition (DDT) distance, but the DDT time decreases as the flame sub-chamber length increases. Conventional spark ignition is investigated as a comparison experiment, and detonation initiation is not observed in mixtures with nitrogen dilution up to 65%.

Processes of suppression and quenching of detonation in a hydrogen–oxygen mixture by means of inserting inert particles into the flow field are numerically studied within the framework of a two-velocity two-temperature model of mechanics of heterogeneous media. The wave pattern in an inert cloud of particles, induced under the action of shock and detonation waves, is determined. The validity of using a one-velocity model for the description of detonation suppression and quenching by clouds of coarse particles is demonstrated. The effect of the volume fraction and diameter of moving particles on the detonation wave velocity is found. The limiting transition from a frozen detonation flow, which is formed in the case of large particle diameters, to an equilibrium flow formed in the case of small particle diameters is studied. Geometric limits of detonation are determined, and a comparison with similar results predicted by the one-velocity model is performed.

Processes of continuous spin detonation and pulsed detonation, as well as combustion of a hydrogen–air mixture in an annular combustor 306 mm in diameter in the regime of air ejection are studied experimentally. The specific flow rates of hydrogen are 0.6–9.8 kg/(s × m²). It is found that the greatest specific impulses of thrust generated by the combustor are reached in the case of continuous spin detonation. On the average, they are greater than the corresponding values by a factor of 1.5 in the case of burning the mixture in streamwise detonation waves, by a factor of 2 in the case of conventional combustion (by a factor of 3 at the maximum thrust impulse of 2200 m/s), and by a factor of 10 in the case of exhaustion of cold hydrogen. A change in the specific flow rate of hydrogen beginning from ≈1.2 kg/(s × m²) corresponding to the maximum thrust impulse decreases its value, and this decrease is more profound as the detonation limits in terms of the specific flow rate of hydrogen are approached. The maximum reactive thrust (83 N) is developed in the examined detonation chamber near the upper limit at the specific flow rate of hydrogen equal to 3 kg/(s × m²).

The effect of the initial temperature of a porous carbon particle on the characteristics of its combustion and spontaneous extinction is analyzed taking into account Stefan flow and heat loss by radiation. It is shown that in the case of forced ignition (increase in the initial temperature of the particle), the diameter and density of the particle after spontaneous extinction remain virtually unchanged. As a result, the extinguished particles have the same diameter but different density. It is shown that the dependence of particle diameter on stationary temperature can be used to determine the maximum combustion temperature and diameter of the particle during its spontaneous extinction. The effect of oxygen concentration on the region of ignition of a porous carbon particle, determined by the initial diameter and temperature of the particle, is analyzed. Analysis of the diffusion-kinetic relations shows that each of the two main heterogeneous reactions of carbon oxidation make similar contributions to the heat and mass transfer of the particle with the surrounding.

Studies on specific thermochemical processes contribute to the understanding of combustion processes and, meanwhile, to the calculus of the safety characteristics and the systems design parameters. In this paper, five different compositions have been studied through TGA and DTA. The reaction rate constants and the activation energies have been determined. Also, the solid combustion products obtained have been evaluated through SEM, EDX, and XPS. Nonisothermal kinetic analyses performed yield results that prove an important difference among the first fire compositions, where the activation energies are considerable, up to 400 kJ/mol, in comparison with the activation energies of the flare compositions, which are lower, 150–250 kJ/mol.

The thresholds of explosive decomposition of PETN (pentaerythrite tetranitrate) with the addition of ultrafine Al–C mechanocomposite particles were measured as a function of the concentration of the latter in the experimental samples exposed to laser pulses (1.064 nm, 12 ns). The sample density was 1.73 g/cm³, and the Al–C particle size at the distribution peak was 220 nm. The minimum threshold of explosive transformation corresponding to a 50% probability of explosion with an energy density of 4 J/cm² was reached at an optimum concentration of the mechanocomposite of 0.1–0.3%. Comparison with experimental data obtained for samples with aluminum nanoparticle additives was performed.

This paper presents the results of experimental determination of the electrical resistivity of an insulating polymer composition (Teflon film and high-vacuum leak sealant) under stepwise shock compression at pressures up to 150 GPa. The data obtained can be used in experiments to measure the electrical conductivity of materials in this range of shock pressures.

This paper considers the use of emulsion explosive compositions to join building bars and replace worn thread in the railway wheel axle. The compositions do not contain individual explosives and greatly increase the safety in explosive working of metals.

The damage characteristics of a typical semiconductor bridge and a micro-semiconductor bridge under the action of an electrostatic discharge are studied in experiments, which include semiconductor film shape measurement, resistance fluctuate evaluation, ignition characteristics, and invalidation threshold voltage measurement. The effect of multiple discharging on the bridge state is also discussed.

The behavior of two new complex salts containing cobalt and tungsten atoms was studied under different thermal conditions. It was found that when heated in air, the salt [Co(NH₃)₆](WO₄)NO₃ exploded at 260 ^oC, and further heating to 800 ^oC led to the formation of a mixture of oxide phases. Heating of [CoEn₃]₂(W₇O₂₄) × nH₂O was not accompanied by explosion and also led to the formation of cobalt and tungsten oxides. The complex salts were used to produce superhard (Vickers microhardness up to 35.8 GPa) coatings on titanium disks by means of shaped-charge explosion. High microhardness is associated with the formation of carbonitride crystalline phases on the target surfaces.

The present study aims at detecting the critical criteria and corresponding critical impact energy for initiation of strain localization during explosive cladding of the Inconel 625 superalloy as a cladding material and low-carbon steel as a substrate. The results do not reveal adiabatic shear bands, which are the main signs of strain localization, within the superalloy in all studied impact energies up to 205 kJ. At impact energies greater than 78–114 kJ, strain localization is observed in low-carbon steel, and microcracks develop within the adiabatic shear bands. The Johnson–Cook model is used to explains the results obtained and to study the thermomechanical behavior of materials.

The first experimental studies of the effect of the laser plasma generated by focused pulsed-periodic radiation of a CO₂ laser on the formation and evolution of combustion in a supersonic flow of homogeneous methane–air mixtures are performed. Results of multispectral investigations testify to a principal possibility of combustion initiation by an optical discharge. Conditions necessary for combustion stabilization are formulated.

The paper presents substantiation of an integrated multidimensional character of the human nature. Interpenetration of mental, sensory and behavioral sides of mental life shows that the person in his/her activity is a very complex self-organizing fractal, transforming the world. Synthesis of anthropological and synergistic approaches establishes the basis of revealing the nonlinearity of the educational process in the university and of its participants. It applies to using the creative capabilities of teachers, students and open educational space. Targeting and structural correspondence between the educational process and the developing individuality of the student coherently connects all the substructures of the process and synchronizes the rate of their evolution. In this case, you can get a system-wide resonant pedagogical result.

In this article we attempted to discover the ontological base of transcending, the most human process of human existence. We also proposed the conditions for reconstruction of transcending in the modern educational system.

There is considered the transformation of values, which is characteristic for the post-modern society and is conditioned by the increasing importance of the value-and-meaning-related perspective in the post-nonclassical science. The value-and-meaning paradigm of the personal development is substantiated, its categorial system is defined. The value-and-meaning paradigm as a methodological basis of post-nonclassical pedagogical psychology is given reason. The development of the value-and-meaning sphere of the pupil is considered both as the purpose and the result of the pedagogical process. There are analyzed the subject and the problems of new areas of psychological and pedagogical science and practice: pedagogical axiology and axio-pedagogics.

The article is devoted to the person’s world image. A fractal-synergetic paradigm is proposed to study this phenomenon. Self-organization of the world image directly influences the changes in person’s behavior. Physical world, neuron networks of the human brain and personality, as a psychological system, form an integrated multilevel system. Establishment, functioning and development of the system is determined by indivisible synergetic principles. Self-organization mechanisms of the person’s world image are similar to the self-organization mechanisms of a social-psychological system. They are interdependent and influence self-organization of multilevel structures. Experimental data of the person’s world image influencing the person’s behavior are provided.

The article presents the main scientific methods towards understanding and studying the problems of inclusion of children with disabilities into the regular education process. The author analyzes the current status and possible prospects of exploration and development of theoretical-methodical basis of inclusive education. The author argues for the significance of the development of methodological bases of inclusive education, taking into account both the Russian realities and the global patterns of integrated education.

The article presents a brief overview of the reduction mechanism as it manifests itself in all levels of human cognition. The reduction mechanism profoundly influences the development of the human knowledge structures, which tends to rely on the experience the person gets from the daily activities. We introduce the reduction as a self-organizing pulsation component in the “primitive-complex” framework, which provides the cognitive system functioning.

The paper examines the theoretical and practical attempts to substantiate what is the structure of the system of values of the future officers of the Interior Ministry Troops of Russia. The author implicitly criticizes some, especially sociological theories of the value systems, pointing to their theological-dichotomous nature, and contrasts them with a version of the structure of values based on a systemic concept due to M.S. Kagan.

The performance criterion of the cultural and professional-pedagogical design of upbringing in the context of personal responsibility for the quality of health as a professional quality will be a change in the personal priorities, conditioned by the degree of compliance with the socially accepted norms, standards and life values and the approved strategies of behavior.

The author analyzes the existing views on the effectiveness criteria of the cognitive activity of the cadets of military institutions. The article describes some of the indicators which influence the professional training level of the cadets. The content of the effectiveness criteria of the cognitive activity is revealed.