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Petroleum 2022年第2期8卷 278-290页

作者： Ivan Makhotin Denis Orlov Dmitry Koroteev evgeny burnaev Aram Karapetyan Dmitry Antonenko Skolkovo Institute of Science and Technology MoscowRussia JSC Zarubezhneft MoscowRussia

Well-known oil recovery factor estimation techniques such as analogy,volumetric calculations,material balance,decline curve analysis,hydrodynamic simulations have certain *** techniques are time-consuming,and require specific data and expert ***,though uncertainty estimation is highly desirable for this problem,the methods above do not include this by *** this work,we present a data-driven technique for oil recovery factor(limited to water flooding)estimation using reservoir parameters and representative *** apply advanced machine learning methods to historical worldwide oilfields datasets(more than 2000 oil reservoirs).The data-driven model might be used as a general tool for rapid and completely objective estimation of the oil recovery *** addition,it includes the ability to work with partial input data and to estimate the prediction interval of the oil recovery *** perform the evaluation in terms of accuracy and prediction intervals coverage for several tree-based machine learning techniques in application to the following two cases:(1)using parameters only related to geometry,geology,transport,storage and fluid properties,(2)using an extended set of parameters including development and production *** both cases,the model proved itself to be robust and *** conclude that the proposed data-driven approach overcomes several limitations of the traditional methods and is suitable for rapid,reliable and objective estimation of oil recovery factor for hydrocarbon reservoir.

关键词： Oil recovery factor Machine learning Regression Uncertainty estimation Conformal predictors Clustering Oilfield Oil reservoir

The Spin-up of a Star Gaining Mass in a Close Binary System on the Thermal Time Scale

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Research in Astronomy and Astrophysics 2022年第10期22卷 158-164页

作者： evgeny Staritsin K.A.Barkhatova Kourovka Astronomical Observatory B.N.Yeltsin Ural Federal Universitypr.Lenina 51Ekaterinburg 620000Russia

We investigate the exchange of mass in a binary system as a channel through which a Be star can receive a rapid *** mass-transfer phase in a massive close binary system in the Hertzsprung-gap is accompanied by the spinning up of the accreting *** consider a case when the mass of the accreting component increases by 1.5 *** component acquires mass and angular momentum while in a state of critical *** angular momentum of the component increases by 50 *** circulation effectively transports angular momentum inside the component during the mass-transfer phase and during the thermal timescale after the end of the mass-transfer *** a result of mass transfer,the component acquires the rotation typical of classical Be stars.

关键词： (stars:)binaries(including multiple) close-stars emission-line,Be-stars rotation-stars early-type

Formation of a Rapidly Rotating Classical Be-star in a Massive Close Binary System

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Research in Astronomy and Astrophysics 2024年第1期24卷 44-50页

作者： evgeny Staritsin K.A.Barkhatova Kourovka Astronomical Observatory B.N.Yeltsin Ural Federal Universitypr.Lenina 51Ekaterinburg 620000Russia

This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange.

关键词： (stars:)binaries(including multiple):close stars:emission-line Be stars:early-type stars:rotation

The Progenitors of Be-stars Paired with O-subdwarfs:The Spin-up of a Be Star at the Stage of Conservative Mass Exchange

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Research in Astronomy and Astrophysics 2024年第11期24卷 104-111页

作者： evgeny Staritsin K.A.Barkhatova Kourovka Astronomical Observatory B.N.Yeltsin Ural Federal Universitypr.Lenina 51Ekaterinburg 620000Russia

The spinning-up of the accreting component in the process of conservative mass exchange is considered in binary systems—progenitors of systems consisting of a main sequence Be-star and an *** the mass exchange,the meridional circulation transfers 80%-85%of the angular momentum that entered the accretor together with the accreted matter to the accretor *** angular momentum is removed from the accretor by the *** the mass exchange finishes,the accretor has a rotation typical of classical Be-type stars.

关键词： (stars:)binaries(including multiple) close-stars emission-line-Be-(stars:)binaries general

Is the additional increase of star luminosity due to partial mixing real?

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Research in Astronomy and Astrophysics 2019年第3期19卷 3-6页

作者： evgeny Igorevich Staritsin K.A.Barkhatova Kourovka Astronomical Observatory B.N.Yeltsin Ural Federal University

The partial mixing of matter between the radiative envelope and convective core in an early Btype star produces an additional increase of star luminosity during main sequence evolution. High quality data on stellar mass and luminosity defined from studies of detached double-lined eclipsing binaries are used to check the existence of such additional increase. It is shown that the additional luminosity increase does not contradict observed high quality data, if the intensity of partial mixing is restricted by the observed increase in surface helium content.

关键词： stars structure and evolution

Special Spectral Approach to Solutions of SISO LTI H-Optimization Problems

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International Journal of Automation and computing 2019年第1期16卷 112-128页

作者： evgeny I.Veremey Faculty of Applied Mathematics and Control Processes Saint-Petersburg State University

The paper is devoted to H-optimization problems for linear time invariant(LTI) systems with scalar control, external disturbance and measurement noise. All these problems can be numerically solved with the help of the well-known universal approaches based on Riccati equations, linear matrix inequalities(LMI) or maximum entropy technique. Nevertheless, in our opinion there exists a possibility to increase the computational efficiency of synthesis using a special spectral approach to the above mentioned problems in frequency domain. Some relevant details are discussed and efficient numerical algorithms are proposed for the practical implementation of spectral approach. One of its virtues is a possibility to present optimal solutions in a specific form, which is convenient for investigation.

关键词： Stabilizing controller performance index synthesis H-optimization spectral approach

Bismuth-doped optical fibers: a challenging active medium for near-IR lasers and optical amplifiers

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Light(Science & Applications) 2012年第1期1卷 105-111页

作者： evgeny M Dianov The Fiber Optics Research Center of the Russian Academy of Sciences 119333 MoscowRussia

It has recently been demonstrated that Bi-doped glass optical fibers are a promising active laser *** types of Bi-doped optical fibers have been developed and used to construct Bi-doped fiber lasers and optical *** paper reviews the recent results regarding the luminescence properties of various Bi-doped optical fibers and the development of Bi-doped fiber lasers and optical amplifiers for the 1150 to 1550 nm spectral region.

关键词： amplifier bismuth fiber laser luminescence

Optical information processing using dual state quantum dot lasers: complexity through simplicity

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Light(Science & Applications) 2021年第12期10卷 2307-2321页

作者： Bryan Kelleher Michael Dillane evgeny A.Viktorov Department of Physics University College CorkCorkIreland Tyndall National Institute University College CorkLee MaltingsDyke ParadeCork T12 R5CPIreland Centre for Advanced Photonics&Process Analysis Munster Technological UniversityBishopstownCork T12 P928Ireland National Research University of Information Technologies Mechanics and OpticsKronverksky Pr.49St.Petersburg 197101Russia

We review results on the optical injection of dual state InAs quantum dot-based semiconductor *** two states in question are the so-called ground state and first excited state of the *** ability to lase from two different energy states is unique amongst semiconductor lasers and in combination with the high,intrinsic relaxation oscillation damping of the material and the novel,inherent cascade like carrier relaxation process,endows optically injected dual state quantum dot lasers with many unique dynamical *** attention is paid to fast state switching,antiphase excitability,novel information processing techniques and optothermally induced neuronal *** compare and contrast some of the physical properties of the system with other optically injected two state devices such as vertical cavity surface emitting lasers and ring ***,we offer an outlook on the use of quantum dot material in photonic integrated circuits.

关键词： state quantum relaxation

New Taxa of Chrysomelidae (Insecta:Coleoptera) from Rovno Amber,Late Eocene

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 772-782页

作者： Konstantin NADEIN evgeny PERKOVSKY Schmalhausen Institute of Zoology National Academy of Sciences of UkraineKievUkraine

Leaf beetles Chrysomelidae of Rovno amber, from the Late Eocene, are recorded and described. Chrysomelidae of Rovno amber are represented by three subfamilies： Galerucinae （Alticini）, Chrysomelinae, and Enmolpinae. Two new genera and three new species of Alticini： Manobiomorpha Nadein, gen. nov. （type species Manobiomorpha eocenica Nadein, sp. nov.）, Psyllototus Nadein, gen. nov. （type species PsyUototus progenitor Nadein, sp. nov.）, and Crepidodera decolorata Nadein et Perkovsky, sp. nov. are described. A new chrysomeline genus and species Paleophaedon minutus Nadein gen. nov. et sp. nov. is described. Probable trophic association of Crepidodera decolorata sp. nov., the taxonomic positions of Manobiomorpha gen. nov. and PsyUototus gen. nov., and the composition of leaf beetle faunas of Middle and Late Eocene of Europe are discussed.

关键词： Chrysomelidae Rovno amber Late Eocene new genera new species

Research on magnetic fields of galaxies using RZ-model

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Research in Astronomy and Astrophysics 2021年第3期21卷 57-60页

作者： evgeny Alexandrovich Mikhailov Vasilii Vladimirovich Pushkarev Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia University of Cambridge Trinity LaneCambridgeCB21TNUnited Kingdom

The generation of magnetic fields of galaxies is usually described by the dynamo *** process is characterized by the Steenbeck-Krause-Radler equation,which is the result of averaging the magnetohydrodynamics equations by distances which are associated with the size of turbulent cells in the interstellar *** equation is quite difficult to solve both from an analytical and numerical point of *** galaxies,the no-z approximation is widely *** describes the magnetic fields in thin *** such objects,where it is important to study the vertical structure of the field,it is not very applicable,so it is quite useful to adopt the RZ-model,which takes into account the dependence of the distance from the equatorial *** our research we have obtained the critical values of the dynamo number for galaxies with large *** have also described typical z-structure for the magnetic ***,we have demonstrated that it is possible to generate dipolar magnetic fields.

关键词： general:dynamo,magnetic fields methods:numerical galaxies:magnetic fields