bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self-excited periodic oscillations in a supersonic laminar flow past a blunt-fin body mounted on a plate
Authors: Kolesnik E V , Smirnovsky A A , Smirnov E M 
Published: December 2020

Abstract
Results of numerical simulation of supersonic gas flow past a blunt fin mounted on a flat plate with developing laminar boundary layer are presented. The calculations cover flow cases with the freestream Mach number of 6.7 and three different Reynolds numbers. A detailed analysis of flow characteristics such as temperature and surface heat flux are presented. In the smaller Reynolds number case, solution is steady-state and agrees very well with known numerical and experimental data. In case of larger Re values, the flow becomes periodic. These regimes are characterized by self-excited non-linear oscillations with almost the same fundamental frequency.
Numerical simulation of the spatio-temporal evolution of the flow in the model of abdominal aorta bifurcation with stenosis in the one of the common iliac arteries
Authors: Sinitsina D E , Zaitsev D K 
Published: December 2020

Abstract
The structure of the pulsating flow in the model of the average configuration, including the bifurcation of the abdominal aorta and subsequent bifurcation of the iliac arteries with axisymmetric hemodynamically significant stenosis in the right common iliac artery, is researched by numerical method. It has been shown that the presence of stenosis in this artery affects the flow structure both downstream and upstream: reverse-flow zones are formed and transverse flow evolution differs significantly from the structure of the flow in a healthy branch. The stenosis with the spatial curves of the model leads to the formation of a stable single-vortex flow in the external iliac artery most of the cardiac cycle. In the mentioned artery of the healthy branch various unstable patterns of two-vortex structure form during the cycle. In both internal iliac arteries, there is a transitional flow, from a two-vortex to a single-vortex motion, forms during the cycle. The influence of the presence of stenosis on the structure of the transverse flow in the internal iliac artery is insignificant. The most likely regions for atherosclerotic lesions of the vascular wall, characterized by the minimum values of time-averaged wall shear stresses and the maximum values of oscillatory shear index, are the stenosis region and the external wall of the common iliac artery.
Calibration algorithm for semiconductor gas sensors and determination of volatile hydrocarbon concentrations in atmospheric air using Fourier transforms
Authors: Kazakov S A , Grevtsev M A , Khavrov G D 
Published: December 2020

Abstract
A calibration algorithm and an algorithm for measuring the concentrations of volatile hydrocarbons in atmospheric air using Fourier transforms for semiconductor gas sensors have been developed. This work presents experimental data on sensor calibrations obtained on certified equipment using gasoline, solvent vapor, toluene, and methane as an example. The calibration carried out by recording measurements of the electrical conductivity of the gas-sensitive layer of the sensor over time, both during heating and cooling samples of sensors based on samarium sulfides and other composite materials. The method of semiconductor gas Fourier spectroscopy that we are developing, the construction principles of which are described in recent publications, is based on the relationship of the obtained calibration characteristics of the sensors of volatile hydrocarbons concentration contained in atmospheric air, with the electrophysical characteristics of samarium sulfide based rare earth semiconductors used as gas sensitive layers.
Self-oscillations of the cutting cutters
Authors: Karpachev A Y 
Published: December 2020

Abstract
The design and construction of products that are subjected to variable forces during operation should be based on calculations of the dynamic properties of the structures being created. This applies most to structures that contain thin-walled elements. In this regard, the development of a reliable method for determining the own dynamic characteristics of cutting tools in the form of cutting circles and cutters is relevant.An engineering method for calculating the frequencies and forms of natural oscillations of disk cutting mills of variable thickness in the radial direction is considered. The results of the calculation were confirmed by the proposed method using data from experiments conducted using unique modern equipment. Thus, it was established that the proposed method can be applied to the analysis of the dynamic properties of the considered type of disk cutting tools and their design with the specified dynamic characteristics. The results obtained are necessary for evaluating the critical operating conditions of the mills under study.
Stabilization of first integrals in optimal control problem
Authors: Kaspirovich K Z 
Published: December 2020

Abstract
The paper considers methods for solving the variational problem of implementing control that stabilizes the optimal movement of the rocket in gravitational fields, finding the most accurate trajectories, and applying the results to solve various practical problems of flight dynamics. The relevance of the study of these problems is due to the fact that space guidance and tracking of the object’s trajectory during the entire flight is the most important basis for a successful space maneuver of ships, satellites, and missiles. Building and implementing in practice the laws of Autonomous guidance in application to modern types of propulsion technology is an acute unsolved problem today, which depends on the ability of aircraft engines to produce the necessary thrust for flight. It takes into account the fact that in reality the object does not fly along the specified trajectory, but has a certain deviation due to inaccuracies in the parameters of the flight model and the propulsion system. Therefore, it is necessary to set the stabilization problem in order to find optimal control conditions. The problems of stabilization and traffic control are important both from a theoretical point of view and because of numerous technical applications. From a theoretical point of view, these problems are important primarily because they relate to complex problems of mechanics, and each time they require new approaches and methods for their solution. In this case, the nature of the problem of motion stabilization depends significantly on the additional conditions that are imposed on the dynamic system.
Displacements of Points of a Viscoelastic Ball Caused by Tides
Authors: Zlenko Aleksandr 
Published: December 2020

Abstract
The derivation of equations of motion is considered in the problem of motion of two viscoelastic bodies in the central gravitational field of massive spherical rigid homogenous body with the help of the d’Alembert Lagrange variation principle. It was used the Kelvin– Voigt model of viscous forces and classical theory of small strains. The method for separation of motions was applied in order to get an approximate solution of quasi-static equation of the theory of elasticity on the unperturbed motion. There were obtained the displacements of each point of the bodies, caused by centrifugal, elastic and dissipative forces.
Optimizing the Forecast Interval for Determine the Parameters of the Earth Pole Motion Model
Authors: Shabunina A.A. , Filippova A.S. 
Published: December 2020

Abstract
The paper provides a solution to the problem of determining the parameters of the model of the Earth pole motion that are optimal from the point of view of the standard deviation. The choice among the considered models is made according to the most accurate forecast on the different time intervals, and the estimate of the approximation interval duration is given that should be used to determine the unknown model parameters from the observational data
Research of Optical Interconnection Technology in Datacenter Networks
Authors: Hao Tianchun 
Published: December 2020

Abstract
In recent years, with rapid development of cloud computing, the business volume of datacenter has increased unprecedentedly and the development of datacenter is facing great challenges. At this point, more efficient interconnection schemes are needed to maintain the increasing demand for communication bandwidth. With its great bandwidth advantage, optical fiber provides low-loss and low-cost solutions for telecom networks. At the same time, compared with the electric interconnection based on copper wire, optical switching technology greatly improves the transmission rate of the communication network. In this paper, the interconnection structure of the datacenter network is studied. Aiming at the interconnection for different top-of-racks (ToR), the c-Through and Helios structures based on photoelectric hybrid technology are reported. Moreover, some structures based on all-optical interconnection such as Proteus, OSMOSIS and IRIS are mentioned. For the interconnection in ToR, arrayed waveguide grating (AWG) based passive optical interconnection and the passive optical couplers-based interconnection schemes are described. Meantime, the main principles, advantages and disadvantages of various structures are analyzed. Finally, the future development of optical interconnection applications is stated.
Analogy of support vector machine and linear regression models in surface roughness prediction
Authors: Hweju Z. , Abou-El-Hossein K. 
Published: December 2020

Abstract
Accurate surface roughness prediction models are an indispensable part of an automated manufacturing system. Since most of the studies on surface roughness prediction have focused on large datasets, it is necessary to shift the focus towards the effectiveness of these models on small datasets. Thus, this study is an analogy of Support Vector Machine (SVM) and Linear Regression Models in surface roughness prediction of single point diamond turned RSA443, using a small dataset. Taguchi’s L9 orthogonal array-based experimental results from single point diamond turning of RSA443 have been integrated into the SVM model development. Primary cutting parameters (cutting speed, feed, and depth of cut) have been utilized, while a fine Gaussian SVM classifier is introduced for the analysis of the input features and surface roughness prediction using the MATLAB classification learner toolbox. The results indicate that the linear regression model is superior to the fine Gaussian SVM model. However, the high prediction accuracy of the fine Gaussian SVM model confirms the suitability of the model as an alternative surface roughness prediction tool. Hence both models can be reliably used for surface roughness prediction of RSA443 using small datasets.
Bubble Deck Slab as an Innovative Biaxial Hollow Slab – A Review
Authors: Siti Quraisyah A A Dyg , Kartini K , Hamidah M S , Daiana K 
Published: December 2020

Abstract
Slab is the most important member in any building structure which consume large amount of concrete. The slab self-weight is large due to large consumption of concrete in producing slab. Therefore, bubble deck slab is an innovative and newly designed biaxial hollow slab system that had been introduced in order to overcome this problem. Bubble deck slab is a revolutionary method which was developed by Jorgen Bruenig from Denmark in the 1990s. The bubble deck slab had been designed and constructed with plastic hollow bubbles in the middle part of slab to eliminate the concrete which does not perform any structural function and at the same time reducing the slab self-weight. Thus, the self-weight of bubble deck slab can be reduced about 30-50% than conventional concrete slab; that can reduce the loads acting on columns, walls and foundations. Finally, the use of bubble deck slab can give many benefits as compared to conventional concrete slab such as improve the structural performance of slab, reduce the materials and cost, efficiency and faster construction time, and it is also a green product. The aim of this paper is to give some of the reviews from previous studies related to bubble deck slab.
Effect of carbon fiber nanostructure on surface morphology under high-fluence ion irradiation
Authors: Andrianova N N , Borisov A M , Makunin A V , Mashkova E S , Ovchinnikov M A , Vysotina E A 
Published: December 2020

Abstract
The results of experimental study of the surface nano-and microstructuring of polyacrilonitrile (PAN) based carbon fiber VMN-4 and viscose based carbon cloth TGN-2MK under 30 keV Ar+ irradiation are presented. Scanning electron microscopy shows a strong difference in evolution of ion-induced morphology for these two carbon fiber types. At sufficiently high fluences, a corrugated morphology is formed on the PAN based carbon fiber, while a network of nanowalls is formed on the viscose based carbon fiber. The found differences are associated with a significant effect of the structure of the surface layer of carbon fiber on ion-induced dimensional changes.
Ion-plasma modification of the surface of light fiber materials
Authors: Andrianova N N , Borisov A M , Krit B L , Mashkova E S , Ovchinnikov M A , Timofeev M A , Umarov F F 
Published: December 2020

Abstract
The results of experimental study of the irradiation under 30 keV Ar+ with the temperature ∼250 °C of viscose based carbon cloth TGN-2MK and SU-2500 glassy carbon are presented. According to the scanning electron microscopy and Raman spectroscopy, modified layer of TGN-2MK obtained by ion irradiation is similar of modified layer of the glassy carbon in the structure and morphology. The formation of nanoscale wall in both cases occurs during graphitization under conditions of dynamic annealing of radiation damage.
Effect of bias voltage on texture formation in TiN, ZrN, Ta, Nb and W coatings
Authors: Betsofen S Ya , Petrov L M , Lozovan A A , Lenkovets A S , Grushin I A , Lebedev M A 
Published: December 2020

Abstract
The effect of the reference voltage on the texture in TiN, ZrN, Nb, Ta and W coatings obtained by PVD methods was investigated by X-ray method. It is shown that an increase in the reference voltage leads to an increase in the {111} texture to a weakening of this texture in W coatings. The results were interpreted on the basis of the features of elastic anisotropy in the material of coatings with a cubic lattice.
Nondestructure diagnostics of surface layers elements content for cylindrical shape material objects
Authors: Egorov V K , Egorov E V 
Published: December 2020

Abstract
The methodics background for the nondestructive element concentration diagnostics of cylindric shape material objects surface layer is developed. The diagnostics is produced without objects form-factor distortion on base of ion beams and X-ray analytical methods. The depth element concentration distribution determination found on the ion beams Rutherford backscattering data and results of X-ray fluorescence testing in conditions of TXRF modified measurements. Possibilities of the elaborated analytical conception are illustrated by experimental data obtained at study of element content in surface layer of the nuclear heat release cell shell.
Effects of different nanoparticles additions on composition and properties of oxide layers formed by plasma electrolytic oxidation on cast Al-Si alloy
Authors: Polunin A V , Borgardt E D , Shafeev M R , Katsman A V , Krishtal M M 
Published: December 2020

Abstract
The effect of additions to the electrolyte of SiO2, Si3N4, Y2O3, WC and TiC nanoparticles (NPs) with a similar particle size on the structure, composition and properties of oxide layers formed by plasma electrolytic oxidation (PEO) on a cast Al-Si alloy 357.0 (7.5 wt % Si) was investigated. The oxide layers were studied by scanning electron and confocal laser microscopy (SEM and CLSM), energy dispersive X-ray microanalysis (EDXMA), X-ray diffraction analysis (XRD), and instrumental indentation. The thickness, roughness, microhardness and wear resistance of the oxide layers were determined. A complex positive effect of all types of particles added to the electrolyte on the hardness and wear resistance of the oxide layers has been established. The greatest positive effect was exerted by the addition of tungsten carbide NPs to the electrolyte – an increase in the average microhardness from 882 MPa in the base version to 1354 MPa and a decrease in the average reduced wear from 592 ng/(N*m) to 65 ng/(N*m), respectively.
Starch based antimicrobial food packaging film towards a sustainable environment
Authors: Mallick N , Pal D , Soni A B , Jhariya D C , Singh D 
Published: December 2020

Abstract
Smart biodegradable packaging materials help restrict food-borne pathogens and reduce wastage of food items. Normally, food is packaged in plastic films, which are seldom reprocessed, which ultimately leads to an adverse impact on the environment. However, our ecosystem can be preserved by the use of biodegradable packaging materials. Deterioration of food caused by food-borne pathogens and microorganisms represent a severe problem. Therefore, a highly encouraging active packaging innovation is the antimicrobial packaging. Various active compounds can be incorporated in the packaging film to extend the shelf-life of packaged foods. The starch-based film is considered as a cost-effective material for antimicrobial packaging. Moreover, essential oils can be incorporated to enhance the antimicrobial effect, i.e., slow down food-borne pathogens. This paper systematically examines the impact of three essential oils (cloves, basil, and cinnamon) on biodegradable starch-based film’s antimicrobial action. Three pathogenic microorganisms, namely; Staphylococcus aureus, Bacillus cereus, and Escherichia coli were are used for the assessment of antimicrobial properties. All the films containing different essential oils have shown a significant antimicrobial action against all the three microbes studied in this work.
Special aspects of uranium oxide non-stoichiometry measurement by thermogravimetric analysis
Authors: Tenishev A , Kuzmin R , Matvenov M , Mikhalchik V , Shornikov D 
Published: December 2020

Abstract
Thermogravimetric analyses for determining uranium dioxide non-stoichiometry have been reviewed. Parameters of oxidation in air at various temperatures have been examined. The key parameters affecting accuracy of the obtained results have been evaluated. Oxidation parameters have been proposed, both for pure uranium dioxide as well as for uranium dioxide with added gadolinium oxide, which makes it possible to determine oxygen to metal (O/M) ratio with at least ±0.002 accuracy in weighed sample portions of approximately 3 g.
Radiation effects in coatings ZrTiN induced by impact of high energy krypton ions
Authors: Adabergenova T , Kislitsin S , Uglov V , Ivanov I , Larionov A , Ryskulov A 
Published: December 2020

Abstract
This paper presents research results of the impact of high-energy krypton ions on structure and mechanical properties of ZrTiN coatings. The ZrTiN coatings were synthesized by the magnetron sputtering method on the substrates from Cr18Ni10Ti steel. Samples irradiated by 84Kr14 with energy 125 MeV to fluence 1016 cm−2 at room and 600°C temperatures. It established that irradiation resulted in significant changes in the surface structure, i.e. appearance of the coral-like structure. Formation of coral-like structure leads to degradation of mechanical properties such as hardness and corrosion resistance. Most significant changes surface structure and properties of coating observed after irradiation at room temperature.
Oxidation of boron-titanium thin film coating during cyclic tests on thermal shock
Authors: Suslov E E , Larionov A S , Kislitsin S B , Chernov I I , Staltsov M S , Dikov A S , Firsova V V 
Published: December 2020

Abstract
The results of experiments on cyclic thermal shock tests of promising neutronabsorbing titanium boride coatings are presented. It has been established that the main effect is the high-temperature oxidation of titanium boride with the formation of titanium and boron oxides. The regularities of changes in the oxidation parameters during cyclic thermal shock tests are determined.
Study of Ti-Zr-Nb-Be filler metal interaction with silicon carbide based ceramics during brazing process
Authors: Eroshenko A A , Ivannikov A A , Fedotov I V , Suchkov A N , Dzhumaev P S , Sevryukov O N 
Published: December 2020

Abstract
This work is devoted to an analysis of the composition of a silicon carbide based ceramic brazed seam as a result of its interaction with rapidly quenched titanium-zirconium-niobium-beryllium filler metal. Structural-phase studies based on EDX and EBSD analysis, mechanical shear tests, and microhardness measurements of brazed joints were carried out. It was shown that titanium, zirconium, and niobium silicides as well as particles of titanium carbosilicides and silicon carbides in the silicon matrix are formed in the brazed seam, probably because of the presence of free silicon in the base material, which leads to increasing joint microhardness and unstable shear strength results.
Durability Studies of Solid Pellets from Torrefied Leucaena Leucocephala
Authors: Wei C K , Mohamed A R , Zin A M , Salleh N H M , Aziz A H A , Kasim M Q C 
Published: December 2020

Abstract
Torrefaction of Leucaena Leucocephala was performed in a fixed bed reactor at temperature of 300 °C and 20 minutes holding time under inert environment. The torrefied Leucaena Leucocephala was pelletized with starch as the binder. Two parameters were investigated such as different ratio of starch addition to torrefied Leucaena Leucocephala pellets and the thickness of torrefied Leucaena Leucocephala pellets towards its durability. The ratios of starch addition to torrefied Leucaena Leucocephala pellets studied were 0, 5,10,15,20 and 25 wt%. Meanwhile, the studied thickness of torrefied Leucaena Leucocephala pellets were 0.3, 0.4, 0.5, 0.6 and 0.7 cm. It was observed that when the ratio of starch addition to torrefied Leucaena Leucocephala pellets was varied from 0-25 wt%, the durability increased steadily and the highest durability of 56.06% was achieved at 20 wt%. When the thickness of torrefied Leucaena Leucocephala pellets was increased from 0.3-0.7 cm, the highest durability of 93.18 % was achieved at 0.5 cm thickness. Scanning Electron Microscope (SEM) analysis was performed on the torrefied Leucaena Leucocephala pellets of 0 and 20 wt% ratio of starch addition. SEM images show the existence of some minor pores on the surface of torrefied Leucaena Leucocephala pellet at 250X and 1000X magnifications.