bluuebunny/crossref_metadata_2025_split huggingface dataset:
Side-channel attack-resistant AES S-box with hidden subfield inversion and glitch-free masking
Authors: Li Xiangyu , Jiao Pengyuan , Yang Chaoqun 
Published: March 2021

Abstract
A side-channel attack (SCA)-resistant AES S-box implementation is proposed, which is an improvement from the power-aware hiding (PAH) S-box but with higher security and a smaller area. We use the composite field approach and apply the PAH method to the inversion in the nonlinear kernel and a masking method to the other parts. In addition, a delay-matched enable control technique is used to suppress glitches in the masked parts. The evaluation results show that its area is contracted to 63.3% of the full PAH S-box, and its power-delay product is much lower than that of the masking implementation. The leakage assessment using simulation power traces concludes that it has no detectable leakage under t-test and that it at least can thwart the moment-correlation analysis using 665 000 noiseless traces.
Energy band adjustment of 808 nm GaAs laser power converters via gradient doping
Authors: Zhao Yingjie , Li Shan , Ren Huixue , Li Shaojie , Han Peide 
Published: March 2021

Abstract
The gradient doping regions were employed in the emitter layer and the base layer of GaAs based laser power converters (LPCs). Silvaco TCAD was used to numerically simulate the linear gradient doping and exponential gradient doping structure, and analyze the transport process of photogenerated carriers. Energy band adjustment via gradient doping improved the separation and transport efficiency of photogenerated carriers and reduced the total recombination rate of GaAs LPCs. Compared with traditional structure of LPCs, the photoelectric conversion efficiency of LPCs with linear and exponential gradient doping structure were improved from 52.7% to 57.2% and 57.7%, respectively, under 808 nm laser light at the power density of 1 W/cm2.
Film flows with recirculation: hydrodynamics and heat transfer
Authors: Solodov A P 
Published: March 2021

Abstract
Hydrodynamics and heat transfer in film flows along solid surfaces are analyzed by numerical simulation. The current version of the Kolmogorov-Prandtl turbulence model is used to obtain a compact mathematical description focused on engineering applications in power engineering and other heat technologies. Film flows with recirculation are studied as special modes of condensing (or evaporative) devices of power plants. Other possible applications are the problems of evaporative cooling, problems of hydraulic roughness of technical surfaces, technologies of thin-film materials and – in the field of large linear scales - modeling of some natural catastrophic phenomena, such as mudflows. The mathematical description is presented as a system of three ordinary first-order nonlinear differential equations - for distributions of turbulent energy, turbulent energy flux density, flow velocity. The phenomena of laminar – turbulent transition and special modes of “flooding” of the flow are diagnosed. Temperature distributions are calculated and heat fluxes are determined. The Reynolds number of the film and the Stanton number are presented as functions of two dimensionless determining parameters specifying the film thickness and the ratio of the friction stresses at the boundaries.
Hydrodynamics of coolant in VVER reactor core with fuel assemblies of various designs
Authors: Dmitriev S M , Gerasimov A V , Dobrov A A , Doronkov D V , Liskova V E , Rubtsova E V , Ryazanov A V , Khrobostov A E 
Published: March 2021

Abstract
The article presents the results from experimental investigations into local coolant flow fluid dynamics that were carried out on the fragmental model of a VVER-type pressurized water reactor’s mixed core consisting of two types of fuel assemblies (FAs): TVSA-T (one segment) and TVSA-T.mod.2 (two segments). The coolant flow processes in the fuel rod bundle were simulated on an aerodynamic test bench. The pressure field in the flow was measured using a five-channel pneumometric probe. The obtained pressure field in the flow was recalculated for the coolant velocity vector according to the dependences derived during calibration. For drawing up a detailed flow motion pattern, a characteristic model cross section area was separated, which included the space between the assemblies and four fuel rod rows in each TVSA-type fuel assembly. The spatial distribution of coolant flow velocity projections was analyzed, as a result of which it became possible to reveal the regularities associated with the streamlining of spacer, mixing-, and combined-spacer grids in TVSA assemblies by coolant; to determine coolant cross flows resulting from streamlining of hydraulically nonidentical grids and to determine their localization in the experimental model longitudinal and cross sections; and to reveal the effect of accumulating flow hydrodynamic disturbances in the model longitudinal and cross sections resulting from the staggered arrangement of hydraulically nonidentical grids. The results obtained from investigations of interassembly interaction of coolant between the neighboring TVSA-T and TVSA-T.mod.2 assemblies have been adopted for practical use at JSC “Afrikantov OKBM” in estimating the thermal reliability of VVER-type reactor cores and have been included in the database for verification of computation fluid dynamics computer programs (CFD codes) and detailed cell-wise numerical analysis of VVER reactors’ core.
Non-contact heat transfer models identification: Laser hyperthermia of superficial human tissues
Authors: Semenov D S , Nenarokomov A V , Budnik S A 
Published: March 2021

Abstract
Planning and predicting the processes of biological tissues heating associated with therapeutic effects involves high-precision mathematical modelling. However, the thermophysical properties of tissues can vary greatly from patient to patient. The paper presents a computational and experimental method for identifying mathematical models of heat transfer, not involving the placement of temperature sensors inside of the studied object. The experimental setup consists of a flat sample of the material, a laser setup, and a thermal imaging camera. The surface thermal response to the pulsed heat flux of the laser is an array of input data for the developed software package. The heat transfer coefficient and heat flux density are determined iteratively by minimizing the residual functional between the calculated and experimental values. The method was tested when determining the characteristics of a specimen of low-pressure polyethylene. The result was obtained in 5 iterations and under the influence of external natural convection, and without taking into account the translucency of the material, a discrepancy of calculated and experimental values of 3.5% was shown. The method can be used to plan the therapeutic process in order to ensure its maximum effectiveness.
Application of the homogenous nucleation theory to the study of explosive boiling of superheated liquid drops
Authors: Mayorov V O , Yastrebov A K , Levashov V Yu 
Published: March 2021

Abstract
In the work, a model of explosive boiling of a single droplet was proposed, which is based on the classical nucleation theory. A criterion is proposed for estimation the droplet’s lifetime. Calculations were made for droplets of liquid oxygen in saturated vapor. Analysis is made for influence of the initial temperature and droplet size on its lifetime.
Studies of coal and coke ignition intensified by copper salt additives
Authors: Larionov K B , Zenkov A V , Mishakov I V , Kaltaev A Z , Bauman Y I , Gromov A A 
Published: March 2021

Abstract
Process of coal and semi-coke ignition modified with copper salts (Cu(NO3)2, Cu(CH3COO)2 and CuSO4) in amount of 5 wt.% was studied. Application of additives to coal and semi-coke samples was carried out by incipient wetness impregnation method with preliminary dissolution of the additive in an aqueous-alcohol solution with a volume ratio of C2H5OH/H2O = 50/50. Combustion of coal samples has been conducted in combustion chamber at temperatures of the heating medium 500-700 °C. Ignition time was recorded using high-speed video recording. Application of copper-salt additives helped to reduce ignition delay time for samples of BC and SC series by 1.9 and 2.2 times, respectively. The maximum change in the minimum ignition temperature for samples of BC and SC series was 70 °C and 135 °C, respectively.
Swirl Flow Crisis and Its Manifestation in Various Energy Systems
Authors: Mitrofanova O V , Bayramukov A S 
Published: March 2021

Abstract
Conducted analytical studies have shown that in complex geometry channels with three-dimensional curvature, and a variable cross-section area, the conditions leading to large-scale vortex formation and swirl flow. In this case, not only the mode of swirl flow can be implemented, but also the effect of locking the flow due to the crisis of the swirl flow. It is shown that the crisis of swirl flow can take place in various power, motor, chemical-technological devices and other technical devices associated with the use of high-speed swirl flows of liquids or gases. A characteristic feature of such devices is the presence of large pressure losses required for the organization of flow swirling in channels of complex geometry. In the present paper, the manifestation of the swirl flow crisis is considered on the example of modeling the processes of hydrodynamics and heat exchange in the channels of an icebreaker steam generating installation.
CFD-calculation of influence of impurities on the characteristics of a helium turboexpander
Authors: Sidorov A A , Yastrebov A K 
Published: March 2021

Abstract
The process of expanding of two-component gaseous mixture was studied in a stage of a turboexpander unit in three-dimensional unsteady setting with use of methods of computer fluid dynamics. The calculation method used in this work made it possible to study the turboexpander unit in a single calculation model but not in parts due to the use of sliding interfaces. Based on the distribution of the supersaturation ratio, assumption was made about the possible localization of phase transitions in the flow part of the stage of the turboexpander unit, confirmed by the characteristic impeller damage.
Determining the smoke-generating ability of modern cable products needed to model fires in energy facilities
Authors: Puzach S V , Mustafin V M , Akperov R G 
Published: March 2021

Abstract
A comparative analysis of methods of carrying out fire tests was carried out in order to obtain the value of smoke formation coefficient required for simulation of fire dynamics at power engineering facilities. A new method of carrying out fire tests to determine smoke-forming ability of substances and materials is proposed. Results of measurements of radiant heat flux density and gas medium temperature inside combustion chamber at different distances from heating element are presented. The effect of the sample area, the density of the heat flow incident on the sample and the temperature inside the combustion chamber on the value of the smoke formation coefficient is shown. For modern types of cable products used at power engineering facilities, values of smoke formation coefficient under different modes have been determined. Dependence of smoke formation coefficient on sample area and on distance from heating element inside combustion chamber is obtained. A comparative analysis of the results obtained at different facilities with the values given in the database of typical fire load was carried out. It was found that the experimental value of smoke formation coefficient differs significantly from the values obtained in the standard ГOCT12.1.044 facility. The results were analyzed.
Physical simulation of blood flow in a femoropopliteal artery graft
Authors: Mikheev N I , Molochnikov V M , Paereliy A A , Dushina O A 
Published: March 2021

Abstract
The paper describes a new experimental setup intended for simulation of blood flow through stenosis or distal end of anastomosis. The setup is able to reproduce flow rate pulsations with a wave form identical to the one of real blood flow during a cardiac cycle, including the high-amplitude antegrade peak and flow reversal. The design of experimental setup provides stable average flow rate in the test section and repeatability of simulated flow regimes.
Recommendation for prediction of pool boiling heat transfer of various liquids on microstructured surfaces
Authors: Aksianov R A , Kokhanova Y S , Kuimov E S , Ley R A , Popov I A , Skrypnik A N 
Published: March 2021

Abstract
Recommendations for prediction heat transfer coefficients and critical heat flux according to available in the literature experimental data of heat transfer and critical heat flux for boiling different liquids on microstructured surfaces made by deformed cutting method are obtained. In the work, on available in the literature sources of experimental data on heat transfer and critical heat flux at boiling of various liquids on the microstructured surfaces made by the deforming cutting method, recommendations for prediction of heat transfer coefficients and critical heat fluxes are received. Microstructured surfaces allow to intensify the heat transfer is 1.1 to 6 times. Due to the variable wettability of microstructured surfaces elements, critical heat flux increase before 4 times. The proposed criteria equations allow predicting heat transfer coefficients with an error of 30%, and critical heat fluxes with an error of 30-35%. In order to improve the accuracy of forecasting, the possibility of using an artificial neural network model for generalizing heat transfer coefficients is shown. Forecasting using an artificial neural network model allows us to determine the heat transfer coefficients with an error of ±20%.The equations are of interest for designing cooling systems for microelectronic devices, heat and mass transfer devices, boiling zones of heat pipes and thermosyphons, etc.
Air breathable thermal insulation with heat transferintensifiers for high-temperature installation
Authors: Vu S K , Glazov V S , Kobzeva A A 
Published: March 2021

Abstract
To increase the efficiency of the high-temperature installation (HTI), several design options for air-permeable insulation in the outer furnace body are considered, differing in the location of heat-exchange intensifiers(HEI) - dimples in the form of spherical segments. As a result of a computational experiment, an option was established in which the heat losses are minimal, and the temperature of the heated air directed to combustion is maximum.
Calculation of sputtering yields of SiO2 layers from the Si surface by helium ions bombardment
Authors: Manukhin V V , Manukhin M V 
Published: March 2021

Abstract
An analytical model of the sputtering of two-component layered inhomogeneous targets by light ions bombardment has been developed, an analytical formula has been obtained, which makes it possible to calculate the total and partial sputtering coefficients of a binary layer of target heterogeneity by light ions bombardment. The formula obtained is used to calculate the sputtering coefficients of silicon oxide layers from the surface of a uniform silicon substrate. The calculation results are in good agreement with the data of computer simulation.
Thermal Conductivity of Phase Changing Materials Doped with Carbon Nanotubes
Authors: Bocharov G S , Gerasimov D N , Grigoriev I S , Dedov A V , Zverev M A , Eletskii A V 
Published: March 2021

Abstract
Phase changing materials (PCM) can accumulate and release a great quantity of energy at changing the temperature in result of the phase transition. This permits one to use PCMs as a basis of thermal accumulators storing the thermal energy at elevated temperatures and releasing it at lowering the temperature below the phase transition point. Worldwide usage of PCMs in building technology and other fields is hindered by a rather low thermal conductivity coefficient of the most PCMs which makes the response of the relevant thermal accumulators too slow and limits the possibilities of application of such devices. This drawback can be overcame through doping a PCM with particles having high thermal conduction coefficient. The present article contains results of experimental and theoretical investigations of heat propagation in PCM doped with carbon nanotubes the thermal conduction coefficient of which exceeds that of the most PCM by 4 – 5 orders of magnitude. Paraffin П-2 have been used as PCM. The experiments performed demonstrate a 2 – 3 times enhancement of thermal conductivity and 16 orders of magnitude enhancement of the electric conductivity because of doping paraffin with 10% multi-walled nanotubes. The propagation of both heat and electric current has a percolation character, so that nanotubes form conductive paths at exceeding some concentration of the dopant. The heat propagation process was modelled through the solution of the non-stationary heat conduction equation with taking into account the sorption of heat due to the phase transition. The calculations performed for composite materials with the varied thermal characteristics of a material imply that the characteristic heating time is proportional to the value of the melting enthalpy and inversely proportional to the value of the heat conduction coefficient.
ThinFilmsAnalysisMPEI – Software for XPS Analysis of Multilayer Multicomponent Films
Authors: Lubenchenko A V , Lubenchenko O I , Ivanov D A , Ivanova I V 
Published: March 2021

Abstract
The work presents ThinFilmsAnalysisMPEI software implementing the method of chemical and phase depth profiling based on photoelectron spectra interpretation, described in paper [1]. Efficiency and productivity of the software for the problem of chemical and depth profiling is shown on examples of synthetic and experimental spectra.
Structure and thermal conductivity of multi-layer Boron Nitride nano-onions medium size groupe
Authors: Zarichnyak Yu P , Ivanov V A , Marova A A , Khodunkov V P 
Published: March 2021

Abstract
The structure of multilayer concentric nano-particles of boron nitride (borofen), the so-called “nano-onions” promising for creating ultra-hard sintering material, is considered. A model of the structure of hollow multilayer boron nitride nanoparticles of a medium-sized group (30 <D <100 nm, the number N of layers from 2 to 100) and an approximate estimation method for the range of changes in their effective thermal conductivity depending on the size of the nanoparticles and the number of layers are proposed
Phase Transitions of n-Hexane–Water Binary Mixtures (0.5 Mole Fraction)
Authors: Bazaev E A , Bazaev A R , Osmanova B K , Dzhapparov T A G 
Published: March 2021

AbstractBy the method of constant volume piezometer among the isochores new values of p,T andp,ρ,T- relations of n-hexane– water binary mixture (0.5 mole fraction) in three phase (llg) and two phase (ll and lg, l-liquid, g – gas) regions, over the wide temperature range from 373.15 to 673.15 K, pressures between 0.2 and 56 MPa and densities between 55 kg/m3and 554 kg/m3are obtained.Using isochoric P-T break point technique the values of the phase transition parameters (llg ⇄ll, llg⇄lg and ll⇄lg) on p,T – plane were determined and phase coexistence curves in different thermodynamic sections (p,ρ,T)Xwere built.The dependence of pressure from temperature, density and composition along the phase coexistence curve is described by three parameter polynomial represented by expansion of the compressibility factorZs=psVms/RTs=ps/RTsρmsinto a power series of density ω=ρs/ρcand temperature τ=Ts/Tc.Zs=ps/RTsρms=1+∑i=1m∑j=0naijωi/τj,Zs=ps/RTsρms=1+∑i=1m∑j=0naijωi/τj, where ρm-molar density (mol/m3), R=8.314-gas constant (J/mol⋅K). The average relative deviation of calculated values of pressure from experimental ones is not more than 0.1%.
Thermal performance of hybrid thermal interface graphene nanocomposites
Authors: Babenko D D , Dmitriev A A , Dmitriev A S , Mikhailova I A 
Published: March 2021

Abstract
This research examines thermal performance of hybrid thermal interface graphene nanocomposites. Graphene nanoflakes were added in different wt. fractions to thermoplastic polymeric materials (polyacrylate and other polymers) followed by thin film preparation. The prepared thin film samples were characterized using optical and scanning electron microscopy. The fabricated samples of polymer-graphene composites were studied to determine the contact angles at different temperatures and the droplet evaporation rates from the surfaces of such materials.
Protective Coating of Irradiation Device for Fast-Neutron Reactor
Authors: Polunin K K , Mokrushin A A , Bragin S Yu , Kiselev D S , Kuzma-Kichta Yu A 
Published: March 2021

Abstract
The objective of this paper is to select a coating on the surface of zirconium hydride (ZH) in order to reduce hydrogen losses under the operating conditions of an irradiation device of FN-reactors. Tests were carried out on the samples of the moderator units made of zirconium hydride. Oxide, phosphide-oxide and oxide-enamel coatings were considered as a protective layer. Hydrogen yield out of the ZH was studied using a calorimeter and a mass spectrometer by thermal heating of the samples according to the test program (heating rate of 10 °C/min, maximum temperature of 1000 °C, isothermal exposure of 40 min, cooling with a furnace). The hydrogen content in the samples was determined by high temperature vacuum extraction. It is shown the oxide coating is the most technologically advanced and effective. A thermogravimetric analysis of the ZH sample with the protective oxide coating was carried out, and the temperature-time dependence of a stoichiometric coefficient (H / Zr) was determined. The amount of the hydrogen released was determined in a temperature range of 20–1100 °C. The temperature increase in up to 1100 °C leads to almost total loss of hydrogen (98–99 %). In this case, the sample retained its integrity, and the coating exfoliated and fragmented.
Effect of material properties on heat transfer during cooling of high-temperature cylindrical bodies in liquids
Authors: Molotova I A , Zabirov A R , Yagov V V , Vinogradov M M , Belyaev I A 
Published: March 2021

Abstract
The aim of the present paper is an experimental study of the cooling processes of high-temperature cylindrical samples with different thermal conductivity of the metal in liquids. Studying the influence of material properties on heat transfer during cooling and the possibility of accurately prediction of the transition surface temperature to the intensive cooling regime will allow substantiating the choice of a new type of tolerant fuel from the standpoint of thermophysics. The experiments were conducted for cooling in water and ethanol with different subcoolings under atmospheric pressure. For metals with low thermal effusivity, an increase in the transition temperature with a significant increase of the removed heat fluxes from the surface was experimentally discovered.