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Purpose: Experimental determination of vertical dynamic forces of wheel impact on a rail at ballastless construction of railway track RHEDA2000 upper structure with subsequent analysis of obtained data; definition of main factors affecting vertical dynamic force value; identification of dependence of change in the value of wheel vertical dynamic force impact on a rail from motion speed and rolling stock type; calculation of coefficients of vertical dynamics at ballastless construction of rail upper structure. Methods: Measurement of wheel vertical dynamic force impact on a rail was carried out by strain-gauge method (Schlumpf method). Numerical values of those, obtained in the course of experiment, were processed by mathematical statistics method, in its turn, probability level was taken equal to 0.994. Results: The values of vertical dynamic forces of wheel impact on a rail for ballastless structure of RHEDA2000 type at rolling stock different types and various ranges of motion speed have been determined. The dependence of change in the value of wheel vertical dynamic force impact on a rail from motion speed and rolling stock type has been graphically built. Comparison of vertical dynamics coefficients of ballastless construction of railway RHEDA2000 upper structure with the construction of a track on a ballast has been carried out. Practical significance: The obtained results can be used in projection, construction, reconstruction and repair of railway track where track ballastless upper composition is provided.

International audience; In this paper we propose a fluctuation splitting finite volume scheme for a non-conservative modeling of shear shallow water flow (SSWF). This model was originally proposed by Teshukov (2007) in [14] and was extended to include modeling of friction by Gavrilyuk et al. (2018) in [7]. The directional splitting scheme proposed by Gavrilyuk et al. (2018) in [7] is tricky to apply on unstructured grids. Our scheme is based on the physical splitting in which we separate the characteristic waves of the model to form two different hyperbolic subsystems. The fluctuations associated with each subsystems are computed by developing Riemann solvers for these subsystems in a local coordinate system. These fluctuations enables us to develop a Godunov-type scheme that can be easily applied on mixed/unstructured grids. While the equation of energy conservation is solved along with the SSWF model in Gavrilyuk et al. (2018)[7], in this paper we solve only SSWF model equations. We develop a cell-centered finite volume code to validate the proposed scheme with the help of some numerical tests. As expected, the scheme shows first order convergence. The numerical simulation of 1D roll waves shows a good agreement with the experimental results. The numerical simulations of 2D roll waves show similar transverse wave structures as observed by Gavrilyuk et al. (2018) in [7].

A long-wave approximation that describes travelling solitary waves within the framework of the model of a weakly stratified two-layer fluid is considered. It is demonstrated that wave regimes occur near the boundary of the parametric domain of shear instability in the stratified flow. This property offers an explanation for the mechanism of intense mixing in deep bottom layers.

Around the world, parliaments, governments, civil society organizations and even individual parliamentarians are taking measures to make the legislative process more participatory. A key instrument of such measures is e-democracy. In the 1980s, a number of pilot projects on electronic voting and online discussions were introduced. However, only since 2000, with the active development of the Internet, has considerable interest in utilizing electronic initiatives to advance democracy emerge. Today, researchers warn that despite all the talk about “e-democracy,” the circle of actual decision makers is likely to remain as small as it has been heretofore. In this article, the author analyzes the pros and cons of electronic initiatives in the BRICS countries, Europe and the Russian Federation, and provides practical information for improvement. The author suggests that the next step needed to improve civil activity in filing legislative initiatives is the application of a regular mechanism to establish the possibility of organizing the process of civil legislative initiative nomination and the collection of signatures in electronic form, in particular via the Internet, with the possible use of crowd sourcing technologies.

Ovarian hyperstimulation syndrome (OHSS) occurs in practice as a complication in vitro fertilization. The risk of a negative result for embryo transfers significantly increased at OHSS. The search for early markers of OHSS development is relevant. The aim of this study is to identify predictors of moderate OHSS. We analyzed data of young and middle-aged women (20-45 years) before and after hormonal therapy, divided into two groups: 1) without signs the development of OHSS; 2) with initial clinical signs of mild OHSS. We determined hematological parameters (white cell count, red blood cell count, thrombocytes count, white blood cell differential, the erythrocyte sedimentation rate (ESR) and the level of hemoglobin), biochemical parameters (blood test of total protein, the glucose, the creatinine, the alanine aminotransferase and aspartate aminotransferase (ALAT and ASAT, respectively), K , Na ) and coagulometry (the thrombin time, the prothrombin time, fibrinogen, the partial thromboplastin time) of peripheral blood. Statistical analysis consisted of comparing the performance of two research groups using the Mann-Whitney U-test. Significant differences achieved between parameters ESR, ALAT, ASAT and a total protein test in the group with OHSS after removal of mature follicles compared with indicators before puncture and the group without signs of OHSS after follicle puncture. According to literature data these characteristics are out of the range in women with severe OHSS, while follow to our results, only the ESR parameter significantly increased in the group with OHSS. But other serum characteristics were in the normal range, indicating the presence in women of moderate OHSS. ESR, aminotransferase and total protein can potentially use in predicting moderate OHSS in combination with other characteristics.

Two different mathematical models of fluid mechanics are now being investigated at the WSL Institute for Snow and Avalanche Research in Davos to model powder-snow avalanches. The first approach is to solve the full three-dimensional multiphase (ice-dust, air) incompressible Navier-Stokes equations; the second approach is to apply depth-averaged models to simulate both the formation and independent propagation of the powder cloud. The final goal of both models is to predict the dynamics of powder avalanches in three-dimensional terrain and specifically cloud impact pressures. Both models are driven by the same set of terrain dependent mass and momentum exchanges defined by the flow state (speed, density, height) of the avalanche core. The great advantage of the depth-average approach is computational speed, allowing the investigation of different hazard scenarios involving variable release locations, snow temperature and entrainment depths. This fact has allowed the widespread application of the depth-average model to many historical case studies, including the avalanches measured at the Vallée de la Sionne (VdlS) test site. However, a central modelling problem needs to be resolved: both air-entrainment (cloud height and density) and drag (cloud speed) are intimately linked to the turbulence created during the cloud formation phase.In this presentation, we present a depth-averaged turbulence model proposed by V. M. Teshukov [1] and extended by Richard and Gavrilyuk [2] and Gavrilyuk et al. [3], Ivanova et al. [5, 6]. The mathematical model is a 2D hyperbolic non-conservative system of equations that is mathematically equivalent to the Reynolds-averaged model of barotropic turbulent flows. The system is non-conservative, extending the classical shallow water equations to contain three independent components of the symmetric Reynolds stress tensor. We simulate the measured powder cloud heights of two VdlS avalanches using both the incompressible Navier-Stokes and turbulent shallow-water models, capturing the unsteady formation of billow height and width measured by ground based photogrammetry [4]. This can only be achieved by making air-entrainment dependent on the vorticity predicted by the turbulence model. We conclude by summarizing why we believe shallow-water type models can be applied for practical hazard engineering problems.References:[1] V. M. Teshukov in "Gas-dynamics analogy for vortex free-boundary flows.", J. Appl. Mech. Tech. Phys., 2007.[2] G. L. Richard, S. L. Gavrilyuk in "A new model of roll waves: comparison with Brock’s experiments", Journal of Fluid Mechanics, 2012.[3] S.L. Gavrilyuk, K.A. Ivanova, N. Favrie in "Multi-dimensional shear shallow water flows : problems and solutions", Journal of Computational Physics, 2018.[4] Dreier, L., Bühler, Y., Ginzler, C., and Bartelt, P.: Comparison of simulated powder snow avalanches with photogrammetric measurements, Annals of Glaciology, 57, 371 - 381, 10.3189/2016AoG71A532, 2016.][5] K.A. Ivanova, S.L. Gavrilyuk, ”Structure of the hydraulic jump in convergent radial flows”,Journal of Fluid Mechanics, Volume 860, 10 February2019 , pp. 441-464.[6] K.A. Ivanova, S.L. Gavrilyuk, B. Nkonga, G.L. Richard, ”Formation and coarsening of roll-waves in shear shallow water flows down an inclinedrectangular channel”,Computers& Fluids, 159, pp 189203, 2017

In this paper we propose a new reformulation of the first order hyperbolic model for unsteady turbulent shallow water flows recently proposed in Gavrilyuk et al. (J Comput Phys 366:252–280, 2018). The novelty of the formulation forwarded here is the use of a new evolution variable that guarantees the trace of the discrete Reynolds stress tensor to be always non-negative. The mathematical model is particularly challenging because one important subset of evolution equations is nonconservative and the nonconservative products also act across genuinely nonlinear fields. Therefore, in this paper we first consider a thermodynamically compatible viscous extension of the model that is necessary to define a proper vanishing viscosity limit of the inviscid model and that is absolutely fundamental for the subsequent construction of a thermodynamically compatible numerical scheme. We then introduce two different, but related, families of numerical methods for its solution. The first scheme is a provably thermodynamically compatible semi-discrete finite volume scheme that makes direct use of the Godunov form of the equations and can therefore be called a discrete Godunov formalism. The new method mimics the underlying continuous viscous system exactly at the semi-discrete level and is thus consistent with the conservation of total energy, with the entropy inequality and with the vanishing viscosity limit of the model. The second scheme is a general purpose high order path-conservative ADER discontinuous Galerkin finite element method with a posteriori subcell finite volume limiter that can be applied to the inviscid as well as to the viscous form of the model. Both schemes have in common that they make use of path integrals to define the jump terms at the element interfaces. The different numerical methods are applied to the inviscid system and are compared with each other and with the scheme proposed in Gavrilyuk et al. (2018) on the example of three Riemann problems. Moreover, we make the comparison with a fully resolved solution of the underlying viscous system with small viscosity parameter (vanishing viscosity limit). In all cases an excellent agreement between the different schemes is achieved. We furthermore show numerical convergence rates of ADER-DG schemes up to sixth order in space and time and also present two challenging test problems for the model where we also compare with available experimental data.

The mathematical model of shear shallow water flows of constant density is studied. This is a 2D hyperbolic non-conservative system of equations that is mathematically equivalent to the Reynolds-averaged model of barotropic turbulent flows. The model has three families of characteristics corresponding to the propagation of surface waves, shear waves and average flow (contact characteristics). The system is non-conservative: for six unknowns (the fluid depth, two components of the depth averaged horizontal velocity, and three independent components of the symmetric Reynolds stress tensor) one has only five conservation laws (conservation of mass, momentum, energy and mathematical ‘entropy’). A splitting procedure for solving such a system is proposed allowing us to define a weak solution. Each split subsystem contains only one family of waves (either surface or shear waves) and contact characteristics. The accuracy of such an approach is tested on 2D analytical solutions describing the flow with linear with respect to the space variables velocity, and on the solutions describing 1D roll waves. The capacity of the model to describe the full transition scenario as commonly seen in the formation of roll waves: from uniform flow to 1D roll waves, and, finally, to 2D transverse ‘fingering’ of the wave profiles, is shown.

This paper considers issues of legal regulation of moral condemnation of municipal officials and the impact of the recommendations of the Group of States against Corruption (GRECO) on the system of legal regulation of counteraction to Russian corruption. It also examines the concept and principles of anti-corruption, the grounds and procedure for bringing disciplinary proceedings against municipal officials for violating of anticorruption duties as well as issues of compliance with the rules of the Federal laws of the Russian Federation “On Combating Corruption” and “On Municipal Service in the Russian Federation,” and the necessity to unify their content concerning the reasons for dismissal due to the loss of confidence in municipal and state officials for corruption offenses. The Model Code of Ethics and Official Conduct of Civil Servants of the Russian Federation and Municipal Officials is useful to defining the legal status of moral condemnation, the shape of its issuance, scope, duration and legal implications of the use.

International audience; We are interested in modelling of multidimensional turbulent hydraulic jumps in convergent radial flow. To describe the formation of intensive eddies near the free surface (rollers) at the front of the hydraulic jump, a new model of shear shallow water flows is used. The governing equations form a non–conservative hyperbolic system with dissipation source terms. The structure of equations is reminiscent of generic Reynolds-averaged Euler equations for barotropic compressible turbulent flows. Two types of dissipative terms are studied. The first one corresponds to Chézy-like dissipation rate, and the second one to a standard energy dissipation rate commonly used in compressible turbulence. Both of them guarantee the positive definiteness of the Reynolds stress tensor. The equations are rewritten in polar coordinates and numerically solved by using an original splitting procedure. Numerical results for both types of dissipation are presented and qualitatively compared with the experimental works. The results show both experimentally observed phenomena (cusp formation at the front of the hydraulic jump) as well as new flow patterns (the shape of the hydraulic jump becomes a rotating square).

The problem on internal waves in a weakly stratified two-layered flow is studied semi-analytically. The long-wave model describing travelling waves is constructed by means of scaling procedure with a small Boussinesq parameter. It is demonstrated that solitary wave regimes can be affected by the Kelvin–Helmholtz instability arising due to interfacial velocity shear in the upstream flow.

The formation of a periodic roll-wave train in a long channel is studied for two sets of experimental parameters corresponding to Brock’s experiments [3], [4] who measured permanent wave profiles by introducing periodic perturbations at the channel inlet. In both cases, a formed free surface profile is found in good agreement with the experimental results. Qualitative properties of solutions to the model are studied in the case where the perturbation frequency is lower than the experimental one, so longer waves are generated at the channel inlet. It is observed that the corresponding roll-wave train is strongly modulated. In the case where the waves of two different lengths are generated at the channel inlet, the coarsening is observed, i.e. the process where shorter waves disappear progressively by transferring their energy to longer waves forming later a regular roll-wave train. The coarsening phenomenon is always accompanied by a strong modulation. A comparison with the Saint-Venant equations is also performed. The formation of a single wave composing a roll-wave train is also studied in a domain with periodic boundary conditions (called “periodic box”) for the same sets of experimental parameters. The free surface profile is found also in good agreement with the experimental results. This allows us to justify the use of the “periodic box” as a simple mathematical tool for a qualitative study of stability of roll-waves. In particular, we study the stability of a single steady wave by increasing its length. It is shown that the wave becomes morphologically unstable after some critical wave length: it bifurcates into a system of two waves. In the framework of a simplified multi-D model of shear shallow water flows it is also proved that a single steady wave is stable under multi-dimensional perturbations.

In Russia the right to traditional use of lands, biological and other resources such as reindeer pastures, harvesting fauna, fish, non-wood resources of forest including wild plants is declared with due regard to the priorities of indigenous peoples. However, in practice the northern indigenous communities can hardly get an access to their traditional lands. They cannot become owners of hunting lands, fishing areas, cannot obtain long-term licenses for the wildlife use rights, quotes for fishing. Due to many reasons the northern indigenous peoples are not able to compete with major industrial companies. As a consequence, the indigenous peoples do not conduct traditional economic activities, nor do they preserve their traditional lifestyle, values and language. Alongside with guaranteed rules concerning indigenous rights, in the Russian legislation there is a gap in proper regulations of traditional territories use. In the current period of intensive industrial development of the Arctic the legal rules should be revised and supplemented with effective mechanisms of granting and protection of traditional territories and activities of the northern indigenous peoples.

A comparative study of the structural organization, thermodynamic and kinetic properties of the oligodeoxynucleotides complexes formation in the presence of 2,2,2-trifluoroethanol and ethanol in aqueous solution (volume fraction of alcohol 0 to 50 %) was performed. No significant changes in the circular dichroism spectra of oligonucleotides and their complexes at the adding of 50 % v/v alcohol into a solution, was observed, and they retain the profile typical for B-form DNA. The study of the thermal stability of DNA duplexes showed that the increase in the volume fraction of ethanol in the aqueous solution up to 50 % results in a linear decrease in the melting temperature of the intermolecular DNA complexes. In the case of the 2,2,2-trifluoroethanol we observed atypical dependence of thermal stability of DNA duplexes on the fraction of the fluorine-containing co-solvent. Increasing the alcohol fraction from 0 to 20% v/v led to a linear decrease of the melting point of the complex. A further increase in the volume fraction of alcohol (up to 50 %) did not change the thermal stability of the duplexes. It was shown, that the destabilizing effect of the two co-solvents is due to the increase of the dissociation rate constant of the complex and has mainly entropic nature. On the example of oligonucleotides complexes of 8, 12, 15 and 20 base pairs length the possibility of prediction DNA duplexes thermal stability was shown. A model taking into account the change of a number solvent molecules interacting with nucleic acids at the duplex formation in aqueous ethanol (50 % v/v) or trifluoroethanol (20 % v/v) was applied. An accuracy of melting temperature prediction was 1.3 and 0.6 degrees. Using this model, we found that the addition of alcohols in solution leads to an increase in the number of water molecules that bind to a complementary pair of nucleotides at the formation of intermolecular complex (in the presence of ethanol or trifluoroethanol 0.51 ± 0.09 and 1.33 ± 0.12, respectively). At the same time, alcohols interacted with single-stranded oligonucleotides and double-stranded in the same way