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An application of space-filling curves to improve results of turbulent aerodynamics modeling with convolutional neural networks

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Chinese Journal of Aeronautics 2024年第2期37卷 81-92页

作者： mikhail PETROV Sofia ZImINA moscow Institute of Physics&Technology Dolgoprudny 141701Russia

When carrying out calculations for turbulent flow simulation,one inevitably has to face the choice between accuracy and speed of *** order to simultaneously obtain both a computationally efficient and more accurate model,a surrogate model can be built on the basis of some fast special model and knowledge of previous calculations obtained by more accurate base models from various test bases or some results of serial *** objective of this work is to construct a surrogate model which allows to improve the accuracy of turbulent calculations obtained by a special model on unstructured *** this purpose,we use 1D Convolutional Neural Network(CNN)of the encoder-decoder architecture and reduce the problem to a single dimension by applying space-filling *** an approach would have the benefit of being applicable to solutions obtained on unstructured *** this work,a non-local approach is applied where entire flow fields obtained by the special and base models are used as input and ground truth output ***-Allmaras(SA)model and Near-wall Domain Decomposition(NDD)method for SA are taken as the base and special models *** efficiency and accuracy of the obtained surrogate model are demonstrated in a case of supersonic flow over a compression corner with different values for angleαand Reynolds number *** conducted an investigation into interpolation and extrapolation by Re and also into interpolation byα.

关键词： Space-filling curves Convolutional neural network Domain decomposition Turbulent flows Unstructured mesh

Pricing Binary Variables of System-wide Constraints for Power System Optimization

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1131-1144页

作者： Jiaxun Li Wei Lin Zhifang Yang mikhail Davidson State Key Laboratory of Power Transmission Equipment and System Security and New Technology College of Electrical EngineeringChongqing UniversityChongqing 400030China Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong Kong SAR 999077China Faculty of Computational mathematics and Cybernetics Moscow State UniversityMoscow 119991Russia IEEE

With the trend of multiple energies or flexible demand in power systems,binary variables appear in systemwide constraints,which are the foundation of marginal pricing currently in *** appropriate pricing method incentivizes compliance of market participants;otherwise,compliance can be incentivized by paying discriminatory uplift payments which jeopardize transparency of *** paper proposes two theorems to examine whether the binary variables brought by multiple energies and flexible demand will impact compliance under marginal *** first theorem shows sufficient conditions with which marginal pricing with fixed binary variables incentivizes compliance,while the second theorem shows sufficient conditions to require uplift *** improve transparency by reducing uplift payments under cases which fall into the second theorem,this paper further proposes a pricing method by combining 1)designed constraints to price binary variables in system-wide constraints,and 2)convex hull pricing to price binary variables in private *** of the proposed theorems and pricing method is verified in an electricity-gas case(consisting of the IEEE 30-bus system and the NGS 10-node system)and the IEEE 118-bus test system.

关键词： Binary variables impact analysis pricing under non-convexities

A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints

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Defence Technology（防务技术） 2024年第4期34卷 78-133页

作者： Tushar Sonar mikhail Ivanov Evgeny Trofimov Aleksandr Tingaev Ilsiya Suleymanova Department of Welding Engineering Institution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia Department of materials Science Physical and Chemical Properties of MaterialsInstitution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia

The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion *** alloys are manufactured by the equal mixing or larger proportions of five or more alloying *** exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of *** state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA *** HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs *** similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial ***,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNimn and Al_xCoCrFeNi *** state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.

关键词： High entropy alloys Solid state welding microstructure mechanical properties

A rened analytical model for reconstruction problems in diuse reectance spectroscopy

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 33-51页

作者： Ekaterina Sergeeva Daria Kurakina Ilya Turchin and mikhail Kirillin A.V.gaponov-grekhov institute of applied physics of the russian academy of sciences ulyanov st.46 603950nizhny novgorodrussia

A rened analytical model of spatially resolved diffuse reectance with small source-detector separations(SDSs)for the in vivo skin studies is *** to the conventional model developed by Farrell et al.,it accounts for the limited acceptance angle of the *** rened model is validated in the wide range of optical parameters by monte Carlo simulations of skin diffuse reectance at SDSs of units of *** of uniform dermis and two-layered epidermis-dermis structures are *** accuracy of the rened model compared to the conventional one is demonstrated in the separate,constraint-free reconstruction of absorption and reduced scattering spectra of uniform dermis from the monte Carlo simulated *** the case of epidermis-dermis geometry,the recovered values of reduced scattering in dermis are overestimated and the recovered values of absorption are underestimated for both analytical ***,in the presence of a thin mismatched topical layer,only the effective attenuation coe±cient of the bottom layer can be accurately recovered using a diffusion theorybased analytical model while separate reconstruction of absorption and reduced scattering fails due to the inapplicability of the method of ***-ndings require implementation of more sophisticated models of light transfer in inhomogeneous media in the recovery algorithms.

关键词： Diffuse reffectance spectroscopy in vivo skin studies optical properties reconstruction diffuse approximation monte Carlo simulations method of images

Electrically tunable third-harmonic generation using intersubband polaritonic metasurfaces

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Light(Science & Applications) 2024年第8期13卷 1666-1674页

作者： Seongjin Park Jaeyeon Yu Gerhard Boehm mikhail A.Belkin Jongwon Lee Department of Electrical Engineering Ulsan National Institute of Science and Technology(UNIST)UlsanRepublic of Korea Walter Schottky Institute Technical University of MunichGarchingGermany

Nonlinear intersubband polaritonic metasurfaces,which integrate giant nonlinear responses derived from intersubband transitions of multiple quantum wells(mQWs)with plasmonic nanoresonators,not only facilitate efficient frequency conversion at pump intensities on the order of few tens of kW cm^(-2)but also enable electrical modulation of nonlinear responses at the individual meta-atom level and dynamic beam *** electrical modulation characteristics of the magnitude and phase of the nonlinear optical response are realized through Stark tuning of the resonant intersubband *** this study,we report,for the first time,experimental implementations of electrical modulation characteristics of mid-infrared third-harmonic generation(THG)using an intersubband polaritonic metasurface based on mQW with electrically tunable third-order nonlinear ***,we achieved a 450%modulation depth of the THG signal,86%suppression of zero-order THG diffraction tuning based on local phase tuning exceeding 180 degrees,and THG beam steering using phase *** work proposes a new route for electrically tunable flat nonlinear optical elements with versatile functionalities.

关键词： tunable tuning pump

Systemic juvenile idiopathic arthritis–associated lung disease: A retrospective cohort study

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World Journal of Clinical Pediatrics 2024年第1期13卷 73-83页

作者： Konstantin E Belozerov Natalia m Solomatina Eugenia A Isupova Alla A Kuznetsova mikhail m Kostik Department of Pediatric Saint-Petersburg State Pediatric Medical UniversitySaint-Petersburg 194100Russia St.Petersburg State Budgetary Institution of Health Care Children's City Polyclinic No.29 of the Kalininsky District of St.PetersburgSt.Petersburg 195274Russia Research Laboratory of Autoimmune and Autoinflammatory Diseases World-Class Research Centre for Personalized MedicineAlmazov National Medical Research CentreSt.Petersburg 197341Russia

BACKGROUND Lung damage in systemic juvenile arthritis(sJIA)is one of the contemporary topics in pediatric *** previous studies showed the severe course and fatal outcomes in some *** information about interstitial lung disease(ILD)in the sJIA is scarce and limited to a total of 100 *** To describe the features of sJIA patients with ILD in *** In the present retrospective cohort study,information about 5 patients less than 18-years-old with sJIA and ILD were *** diagnosis of sJIA was made according to the current 2004 and new provisional International League of Associations for Rheumatology criteria *** was diagnosed with chest computed tomography with the exclusion of other possible reasons for concurrent lung *** activation syndrome(mAS)was diagnosed with HLH-2004 and 2016 EULAR/ACR/PRINTO Classification Criteria and hScores were calculated during the lung *** The onset age of sJIA ranged from 1 year to 10 *** time interval before ILD ranged from 1 mo to 3 *** disease course was characterized by the prevalence of the systemic features above articular involvement,intensive rash(100%),persistent and very active mAS(hScore range:194-220)with transaminitis(100%),and respiratory symptoms(100%).Only 3 patients(60%)developed a clubbing *** patients(100%)had pleural effusion and 4 patients(80%)had pericardial effusion at the disease *** patients(40%)developed pulmonary arterial ***-related reactions to tocilizumab were observed in 3(60%)of the *** patient with trisomy 21 had a fatal disease *** of the remaining patients had sJIA remission and 2 patients had *** disease improved in 3 patients(75%),but 1 of them had initial deterioration of lung *** patient who has not achieved the sJIA remission had the progressed course of *** cases of hyper-eosinophilia were *** patients(80%)received

关键词： Systemic juvenile arthritis Interstitial lung disease Canakinumab Tocilizumab Interleukin-6 Interleukin-1

Numerical Analysis of Permeability of Functionally Graded Scaffolds

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Fluid Dynamics & materials Processing 2024年第7期20卷 1463-1479页

作者： Dmitry Bratsun Natalia Elenskaya Ramil Siraev mikhail Tashkinov Laboratory of mechanics of Biocompatible materials and Devices Perm National Research Polytechnic UniversityPerm614990Russia

In this work,we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion *** consider two popular solid matrix designs based on triply periodic minimal surfaces,the Schwarz P(primitive)and D(diamond)surfaces,which enable the creation of materials with controlled porosity *** latter property is crucial for regulating the shear stress field in the pores of the scaffold,which makes it possible to control the intensity of cell *** permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the Navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the Darcy or Forchheimer *** calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces,study their properties concerning forward and reverse fluid flows,and determine the ranges of Reynolds number for which the description within the Darcy or Forchheimer model is ***,we obtain a shear stress field that varies along the sample,demonstrating the ability to tune spatially the rate of tissue growth.

关键词： Porous media ﬁltration models scaffolds functionally graded materials

Origin of iron-rich minerals,ooids and pisoids in the Jurassic ooidal ironstones of the Labino-malkin region(Caucasus)

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Journal of Palaeogeography 2024年第3期13卷 475-494页

作者： Natalia A.Kalinina maxim A.Rudmin mikhail Sherstyukov Prokopiy maximov Abdul-Gapur Kerimov Division for Geology School of Earth Sciences&EngineeringTomsk Polytechnic University634050TomskRussia Laboratory of Sedimentology and Paleobiosphere Evolution University of Tyumen625003 TyumenRussia Institute of Earth Science North-Caucasus Federal University355009StavropolRussia

This study investigates the middle Jurassic rocks of the Labino-malkin zone(Caucasus),represented by ooidal ironstones,biogenic limestones,and nodular *** rocks contain ooids/*** on the mineral composition,nine types of ooids and three possible scenarios for their formation have been *** mineral composition of ooids indicates the variable conditions of their deposition and repeated changes in physical and chemical conditions of the environment,including fluctuations in theredox *** access of oxygen in the bottom environment as a factor of increasing oxic conditions was associated with the regression of the sea and/or the inflow of meteoric *** main sources of ooids are the drift of material from the continent and convecting metal-bearing meteoric and/or deep solutions.

关键词： Ooidal ironstones mineral formation Ooids Pisoids mineral chemistry

Conducting Polymer-Based e-Refinery for Sustainable Hydrogen Peroxide Production

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Energy & Environmental materials 2024年第2期7卷 334-342页

作者： Zhixing Wu Penghui Ding Viktor Gueskine Robert Boyd Eric Daniel G■owacki magnus Odén Xaνier Crispin magnus Berggren Emma m.Björk mikhail Vagin Nanostructured materials Department of PhysicsChemistry and Biology(IFM)Linköping UniversitySE 58183LinköpingSweden Laboratory of Organic Electronics Department of Science and Technology(ITN)Linköping UniversitySE 60174NorrköpingSweden

Electrocatalysis enables the industrial transition to sustainable production of chemicals using abundant precursors and electricity from renewable ***-centralized production of hydrogen peroxide(H_(2)O_(2))from water and oxygen of air is highly desirable for daily life and *** report an effective electrochemical refinery(e-refinery)for H_(2)O_(2)by means of electrocatalysis-controlled comproportionation reaction(2_(H)O+o→2HO),feeding pure water and oxygen *** nickel(Ⅱ)oxide(NiO)was used as electrocatalyst for oxygen evolution reaction(OER),producing oxygen at the *** polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)drove the oxygen reduction reaction(ORR),forming H_(2)O_(2)on the *** reactions were evaluated in both half-cell and device *** performance of the H_(2)O_(2)e-refinery,assembled on anion-exchange solid electrolyte and fed with pure water,was limited by the unbalanced ionic *** of the operation conditions allowed a conversion efficiency of 80%.

关键词： conducting polymer hydrogen peroxide nickel(Ⅱ)oxide oxygen evolution reaction oxygen reduction reaction