STRAIN CHARACTERISTICS OF SOILS AND THE METHODS OF THEIR DETERMINATIO

A method is proposed for determining the strain characteristics of soils under dynamic loads, based on the results of experiments on dynamic compression of soils in laboratory conditions on a device of dynamic loading and for solving a wave problem, the statement of which is identical to the statement of the experiment. With the proposed method, the dynamic and static compression moduli, the unloading modulus, the viscosity coefficient of loess soil in the range of seismic loads were determined in accordance with the elastic-viscoelastic soil model developed by G.M. Lyakhov

Application of confidential intervals for verification of reservoir model at interpretation of well test data

The information on arguments of an oil reservoir to a well test from the point of view of the Bayesian inference are express through even allocation of odds in room of arguments. In article application of confidential spacing for a quantitative appraisal of the information receive from the analysis of results of well test which one are us for upgrading of allocations of odds are offered. Use of confidential spacing for an appraisal of a correctness of a choice of a laboratory formation are show

Memory efficient algorithm for solving the inverse gravimetry problem of finding several boundary surfaces in multilayered medium

For solving the inverse gravimetry problem of finding several boundary surfaces in a multilayered medium, the parallel algorithm was constructed and implemented for multicore CPU using OpenMP technology. The algorithm is based on the modified nonlinear conjugate gradient method with weighting factors previously proposed by authors. To reduce the memory requirements and computation time, the modification was constructed on the basis of utilizing the Toeplitz-block-Toeplitz structure of the Jacobian matrix of the integral operator. The model problem of reconstructing three surfaces using the quasi-real gravitational data was solved on a large grid. It was shown that the proposed implementation reduces the computation time by 80% in comparison with the earlier algorithm based on calculating the entire matrix. The parallel algorithm shows good scaling of 94% on 8-core processor. © 2019 Author(s).Ministry of Education and Science of the Republic of Kazakhstan: AP 05133873This work was financially supported by the Ministry of Education and Science of the Republic of Kazakhstan (project AP 05133873)

Separation of reservoir layers based on neuro-fuzzy systems

In the article, the application algorithms of neural network methods for determining the lithological composition of a well bore according to logging data are studied by training based on the analysis of the correspondence of logs to the available expert opinion. Specialized algorithms for processing the results of network operation have been developed to increase the information content of a signal produced by a neural network and to increase the reliability of recognition

Predicting the solvation of organic compounds in aqueous environments: from alkanes and alcohols to pharmaceuticals

The development of accurate models to predict the solvation, solubility, and partitioning of nonpolar and amphiphilic compounds in aqueous environments remains an important challenge. We develop state-of-the-art group-interaction models that deliver an accurate description of the thermodynamic properties of alkanes and alcohols in aqueous solution. The group-contribution formulation of the statistical associating fluid theory based on potentials with a variable Mie form (SAFT-γ Mie) is shown to provide accurate predictions of the phase equilibria, including liquid–liquid equilibria, solubility, free energies of solvation, and other infinite-dilution properties. The transferability of the model is further exemplified with predictions of octanol–water partitioning and solubility for a range of organic and pharmaceutically relevant compounds. Our SAFT-γ Mie platform is reliable for the prediction of challenging properties such as mutual solubilities of water and organic compounds which can span over 10 orders of magnitude, while remaining generic in its applicability to a wide range of compounds and thermodynamic conditions. Our work sheds light on contradictory findings related to alkane–water solubility data and the suitability of models that do not account explicitly for polarity

The chemistry of vibrationally excited H2 in the interstellar medium

The internal energy available in vibrationally excited H2 molecules can be used to overcome or diminish the activation barrier of various chemical reactions of interest for molecular astrophysics. In this article we investigate in detail the impact on the chemical composition of interstellar clouds of the reactions of vibrationally excited H2 with C+, He+, O, OH, and CN, based on the available chemical kinetics data. It is found that the reaction of H2 (v>0) and C+ has a profound impact on the abundances of some molecules, especially CH+, which is a direct product and is readily formed in astronomical regions with fractional abundances of vibrationally excited H2, relative to ground state H2, in excess of 10^(-6), independently of whether the gas is hot or not. The effects of these reactions on the chemical composition of the diffuse clouds zeta Oph and HD 34078, the dense PDR Orion Bar, the planetary nebula NGC 7027, and the circumstellar disk around the B9 star HD 176386 are investigated through PDR models. We find that formation of CH+ is especially favored in dense and highly FUV illuminated regions such as the Orion Bar and the planetary nebula NGC 7027, where column densities in excess of 10^(13) cm^(-2) are predicted. In diffuse clouds, however, this mechanism is found to be not efficient enough to form CH+ with a column density close to the values derived from astronomical observations.Comment: accepted for publication in the Astrophysical Journal; 9 pages, 7 figure

Low-energy quenching of positronium by helium

Very low-energy scattering of orthopositronium by helium has been investigated for simultaneous study of elastic cross section and pick-off quenching rate using a model exchange potential. The present calculational scheme, while agrees with the measured cross section of Skalsey et al, reproduces successfully the parameter ^ 1Z_{\makebox{eff}}, the effective number of electrons per atom in a singlet state relative to the positron. Together with the fact that this model potential also leads to an agreement with measured medium energy cross sections of this system, this study seems to resolve the long-standing discrepancy at low energies among different theoretical calculations and experimental measurements.Comment: 4 latex pages, 3 postscript figure

Decrease of frequency of conversions of short-scar incision to the aorta using pre-operative 3D-modeling on the basis of the changes in aorta and patient's individuality

The increase of the number of patients with atherosclerosis of the aorta leads to steady growth of the number of operations on aorta-femoral segment. In this regard, Federal programs of Federal funding are created for treatment of this disease. However, a high rate of mortality in cases of standard operations causes surgeons to minimize the volume of surgical treatment. The method of operation of the aorta from short-scar incision is studied quite enough; however, there are some problems, such as incision conversion and intraoperative complications. The aim of this study is to improve the results of operations on the aorta from the short-scar incision by access modeling. We analyzed the results of treatment of 88 patients operated from short-scar incision to the aorta in the Kemerovo Regional Clinical Hospital. Patients were divided into two groups - 55 patients operated without access modeling and 33 patients operated with preoperative access modeling. In the result in the second group there was reduction of incision conversions frequency to 3,03%, also there was reduction of the operation time in comparison with the first group without access modeling, with comparable characteristics of the groups and of the same frequency and nature of complications

Reflection-enhanced gain in traveling-wave parametric amplifiers

The operating principle of traveling-wave parametric amplifiers is typically understood in terms of the standard coupled mode theory, which describes the evolution of forward propagating waves without any reflections, i.e., for perfect impedance matching. However, in practice, superconducting microwave amplifiers are unmatched nonlinear finite-length devices, where the reflecting waves undergo complex parametric processes, not described by the standard coupled mode theory. Here, we present an analytical solution for the TWPA gain, which includes the interaction of reflected waves. These reflections result in corrections to the well-known results of the standard coupled mode theory, which are obtained for both three-wave and four-wave mixing processes. Due to these reflections, the gain is enhanced and unwanted nonlinear phase modulations are suppressed. Predictions of the model are experimentally demonstrated on two types of unmatched TWPA, based on coplanar waveguides with a central wire consisting of (i) a high kinetic inductance superconductor, and (ii) an array of 2000 Josephson junctions