Building surrogate models for two-phase flow of fluids in porous media based on spatial radial basis approximation

The paper proposes a method for constructing the surrogate models for two-phase flow based on a combination of finite-difference solutions and fine-grid spatial approximation. The method provides the approximate models for solving optimal control the operating parameters of field development

Radial basis approximation of single-phase flow in porous media based on the Green’s functions

The article discusses the problem of approximating solutions of differential equations describing the process of a two-dimensional fluid flow in porous media. The approximation is presented as a combination of radial basis functions on the basis of the Green’s function is used to solve the Poisson equation with variable coefficients in the case of steady state filtration and parabolic equations in the transient regime. To illustrate the effectiveness of the proposed approximation obtained by the field pressure distribution in the reservoir with a network of injection and production wells. Compare approximated pressure and design points to a satisfactory accuracy of the results

Variations of the McEliece Cryptosystem

Two variations of the McEliece cryptosystem are presented. The first one is based on a relaxation of the column permutation in the classical McEliece scrambling process. This is done in such a way that the Hamming weight of the error, added in the encryption process, can be controlled so that efficient decryption remains possible. The second variation is based on the use of spatially coupled moderate-density parity-check codes as secret codes. These codes are known for their excellent error-correction performance and allow for a relatively low key size in the cryptosystem. For both variants the security with respect to known attacks is discussed

Solving optimization problems of optimal control of operational parameters of oil reservoir

The paper proposes a method for solving optimal control operating parameters of oil stratum: the arrangement of injection and production wells; regulation works well in setting of the two-phase filtration. Depending on the optimization of the planning horizon on the basis of the proposed method gives the prediction of increasing production by 27 % in the long-term planning up to 60 % for short-term planning

Building and optimizing a model of low level for two-phase filtration

The paper proposes a method for constructing models of low level for two-phase flow based on a combination of finite-difference solutions and detailed spatial approximation, providing the possibility of approximating the models for solving optimal control the operating parameters of the oil reservoir

Random mode coupling assists Kerr beam self-cleaning in a graded-index multimode optical fiber

In this paper, we numerically investigate the process of beam self-cleaning in a graded-index multimode optical fiber, by using the coupled-mode model. We introduce various models of random linear coupling between spatial modes, including coupling between all modes, or only between degenerate ones, and investigate the effects of random mode coupling on the beam self-cleaning process. The results of numerical investigations are in complete agreement with our experimental data

Beam self-cleaning in multimode optical fibers and hydrodynamic 2D turbulence

We experimentally demonstrate the conservation of the average mode number in the process of Kerr beam self-cleaning in a graded-index multimode optical fiber, in analogy with wave condensation in hydrodynamic 2D turbulence