bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of superficial gas velocity on heat transfer in a two-phase system with additive heater surfaces
Authors: Eloyan K S , Ronshin F V , Litvintceva A A , Cheverda V V
Published: December 2020

The problem of removing high heat fluxes from a powerful microelectronic element (chip, microprocessor) is one of the most difficult tasks. One of the promising methods for cooling is the use of two-phase systems in a minichannel with a stratified flow regime. Additive technologies allowing the creation of structured surfaces are of increasing interest. The study of heat transfer using structures on the surface in the form of cylindrical protrusions in comparison with a smooth surface with characteristic size (diameter and height) equal to 300 μm is presented in this work.
Kinetic and thermophysical phenomena in the synthesis of porous composites from (Ti+Si) and (Ti+Al+Si) powder mixtures in the reaction sintering mode
Authors: Knyazeva A G , Korosteleva E N
Published: December 2020

Theoretical and experimental study of the synthesis of porous composites from powder mixtures for Ti-Si and Ti-Al-Si systems in the reaction sintering mode is carried out in the present work. The thermokinetic model of reaction sintering is formulated taking into account competing physicochemical stages. The model includes the heat balance equation, the kinetic equations for the components involved in the reactions, the kinetic equation for porosity changing during heating, reaction sintering, and cooling. The melting is assumed to occur within the temperature range of liquidity and solidus. These processes lead to the appearance of local stresses and volumetric changes. The results of experimental studies show good agreement with the numerical calculations.
Numerical simulation of heat transfer in a large room with a working gas infrared emitter
Authors: Borisov B V , Kuznetsov G V , Maksimov V I , Nagornova T A , Gutareva N Y
Published: December 2020

The article presents a new approach to determining the main characteristics of the thermal regime in the buildings and structures heated by the gas infrared emitters, based on the analysis of convective heat transfer in the air and thermal conductivity in the enclosing structures. The authors have considered a mathematical model of turbulent heat transfer in the framework of the standard k-e model under radiant heating conditions. The simulation was carried out for a large room with an approximation to the real operating conditions of an industrial facility. The options for heating an empty room and the room with an object were considered.
Experience in DNS of turbulent free convection in air along an isothermal vertical plate
Authors: Smirnov E M , Levchenya A M , Ivanov N G , Smirnovsky A A , Smirnov P E
Published: December 2020

The paper presents results of direct numerical simulation of the turbulent free convection boundary layer developing along a vertical heated plate up to the local Grashof numbers, Grx, of 8.1010 (Pr=0.7). A span-distributed macro-roughness of a selected form is used for enhancing transition to turbulence, so that the Grx–value corresponding to the end point of transition would be close to that reported for the case of natural transition. The results obtained for the first-and the second-order turbulent flow and heat transfer statistics in the developed turbulent regime are in a good accordance with the experimental data reported by Tsuji and Nagano (1988).
Cylinder diameter measurement with displacement and rotation error correction for non-telecentric optics
Authors: Rakhmanov V V , Dvoynishnikov S V , Semenov D O , Glavny V G
Published: December 2020

The paper presents the implementation of a method for measuring the diameter of cylinders in traffic along a transport line using machine vision systems with correction of the error of displacement and rotation of the product for the case of using non-telecentric optics. Diameters were measured for a set of displacements and rotations of the cylinder, and estimates of the achievable errors of this implementation of the layout of the measuring installation were made.
Hydrogen diffusion in AB5 type metal hydride anodes by potentiostatic intermittent titration technique
Authors: Kazakov A N , Bodikov V.Yu. , Blinov D.V. , Volodin A.A.
Published: December 2020

Metal hydrides are widely used for hydrogen-related energy storage applications due to their high volumetric capacity, safety, and selectivity to absorb hydrogen. One of the main applications of metal hydrides is their use as electrode material in Ni-MH batteries. Metal hydride electrodes provide high energy density, high rate capability, tolerance to overcharge and over-discharge, and no electrolyte consumption during the charge/discharge cycle. One of the key factors of metal hydride electrode performance is a hydrogen diffusion from the electrolyte to the bulk of metal hydride material. In the present study, effective hydrogen diffusion coefficients in AB5 type metal hydride electrodes during the charging process are investigated employing potentiostatic intermitent titration technique.
Heating of a carbon nanotubes array with few-cycle optical pulses
Authors: Konobeeva N N , Belonenko M B
Published: December 2020

In this paper, we investigate the heating of carbon nanotubes under the action of few-cycle optical pulses. Within the framework of the hot electron model, an array of carbon nanotubes which is irradiated by an electromagnetic wave with a high emission intensity is considered. The time-dependence of the generated heat is analyzed for various system parameters (duration of the few-cycle laser pulse and relaxation time of the electrons in carbon nanotubes).
Studying dielectric properties of oil shale
Authors: Zinnatullin R R , Sultanguzhin R F
Published: December 2020

The paper describes the methodology, equipment and results of studying the features of dielectric properties of oil shale in the frequency range for values from values 0.05 to 300 MHz and temperatures for values from 20 to 200°C. It is shown that the dielectric parameters for the studied shale samples are an order of magnitude higher than for terrigenous rocks, and along the layers they are about 1.5 - 4 times higher than across the layers. The dielectric properties of the studied shale are found to undergo dispersion in the range for values from 50 to 125 MHz and have nonlinear temperature dependence.
Simulations of partial discharges in a chain of gas cavities at AC voltage
Authors: Kupershtokh A L , Lazebnyi D B
Published: December 2020

The stochastic model of partial discharges (PDs) in chains of gas caverns in condensed dielectrics is improved. The equations for electric field potential are solved in a region filled by dielectric containing gas caverns. The opportunity of a “relay-race” propagation of PDs in a linear chain of gas caverns under constant and ramp voltage was shown in previous studies. This mechanism is possible if the interval between caverns is relatively small. In this case, the wave of PDs can travel along the chain. This paper is devoted to modelling “relay-race” waves in a zigzag chain of gas-filled caverns under AC voltage.
Formation of periodic surface structures in multilayer amorphous Ge2Sb2Te5 thin films irradiated by femtosecond laser pulses
Authors: Kolchin A V , Shuleiko D V , Zabotnov S V , Golovan L A , Presnov D E , Kaminskaya T P , Lazarenko P I , Kozyukhin S A , Kashkarov P K
Published: December 2020

Phase transitions and periodic surface modification in amorphous Ge2Sb2Te5 thin films on multilayer substrate were revealed as a result of the samples irradiation by femtosecond laser pulses with the wavelength of 1250 nm. Raman spectroscopy revealed partial crystallization in the treated samples. Calculations and analysis of scanning electron and atomic-force microscopy data showed that formation of the periodic surface structures is related to photoinduced surface plasmon-polariton excitation and depends on laser radiation fluence. The obtained results are useful for design and fabrication of new promising data-storage and polarization optics devices.
Numerical simulation of adiabatic shear bands formation processes on two-dimensional eulerian meshes
Authors: Muratov R V , Kudryashov N A , Ryabov P N
Published: December 2020

In this work we suggest a mathematical model of motion of the elasto-plastic materials with nonlinear plasticity constitutive law; we also propose an effective numerical method for numerical simulations of such tasks on two-dimensional eulerian meshes. Based on the method, we research formation of multiple adiabatic shear bands (ASB) at high-speed shear deformations. We test our approach on two-dimensional problem where the initial heterogeneity of temperature leads to formation of adiabatic shear band.
REQUIREMENTS FOR THE DUAL Fe + H/He BEAM AT THE ACCELERATOR HIPR FOR SIMULATION OF NEUTRON INFLUENCE ON NUCLEAR REACTOR MATERIALS
Authors: Fedin P A , Ziiatdinova A V , Pryanishnikov K E , Kuibeda R P , Kulevoy T V , Nikitin A A , Rogozhkin S V
Published: December 2020

Ion accelerator facility is a powerful tool that can be used to simulate neutron irradiation effects in reactor materials. At the NRC “Kurchatov Institute” - ITEP the heavy-ion accelerator HIPr is used for the ion-beam simulation of radiation damage in steels and alloys. Irradiation is provided with the wide range of metal ions (mainly Fe2+). It is essential to include helium and hydrogen beams for the proper simulation of transmutation driven mechanisms of swelling and void formation. Energies, beam line angle and intensity are determined for design of the second beam line for He/H implantation at HIPr.
Simulation of the isothermal and Hugoniot characteristics of organic compounds via the reactive molecular dynamics
Authors: Kozlova S A , Gubin S A , Maklashova I V
Published: December 2020

This article provides the results of reactive molecular dynamics simulation of shock loading of cyclic hydrocarbon C6H6 and isotherm curve of energy-intensive nitramine C4H8N8O8. To describe the interatomic interaction, as well as to analyze the kinetics of decomposition, we used two parameterizations of the reactive force field ReaxFF. In this paper, we compared the capabilities of ReaxFF force fields to describe the kinetics of the decomposition of benzene behind the front of a shock wave and the ability to reproduce phase transformations of carbon under conditions of high pressures and temperatures. The results obtained are in good agreement with the experiment.
Characteristic for long GRBs with high energy component presence, which not required cosmological corrections
Authors: Arkhangelskaja I V
Published: December 2020

Several thousands of gamma-ray bursts were observed by various experiments. During several GRBs very high-energy photons were detected both in space and ground-based experiments (up to some tens of GeV and up to some TeV, respectively). Usually 2 classes of bursts are considered: short and long GRBs separated by t90~2s. Because of several hundreds of GRBs located at high redshift, its sources’ origins nature concluding as cosmological. Therefore correction to cosmological dilation of GRBs t90 should be considered during any analysis of bursts duration. Firstly very high-energy component was observed during GRB 970417a: 18 photons with energy ~650 GeV were registered by Milagrito within t90 interval of this burst. Now several tens of GRBs reveal activity in energy bands up to some tens of GeV and up to some TeV accordingly data of space and ground-based experiments correspondingly. Unfortunately redshift is unknown approximately for half of GRBs with high energy component presence. Here we introduce new parameter Rt is ratio of maximum energy photon arrival time to burst duration and it not required cosmological correction. At least 2 groups of long GRBs could be separated using parameter Rt: for 25% events highest energy gammas detected within t
90 interval, but for other 75% of bursts it registered more than 10 sec. later than one. Moreover, preliminary results of analysis allow concluding 2 subtypes of second group GRBs. For one μ-quantum with maximum energy arrived within t90. For other such photon was registered later than t90. Therefore, the results of preliminary analyses allow conclude long GRBs population inhomogeneity.
The results of analysis of Rich Galaxy Clusters from CfA2 Redshift Survey spatial distribution
Authors: Arkhangelskaja I V , Khanh L N , Galper A M , Dorosheva D N
Published: December 2020

Preliminary results of the investigation of the properties of 7 galaxy cluster from CfA2 redshift survey are discussed in the presented article. Clusters 933, 142, 1046, and 1652 have several peculiarities of the spatial distributions of galaxies. The distributions on absolute magnitude and luminosity represent two areas for clusters 933, 88, 142, 1046, 1101. The investigation of the spatial distribution and other characteristics of 88, 1101, 1046, 142, 933, 1242 and 1652 galaxy clusters allow concluding gravitational lensing effect. Galaxies from these areas are paired accordingly its spectral characteristics and position. Redshifts of these clusters are in the region 0.002 – 0.022. Preliminary results of analysis allow us concluding compact objects or dark matter blobs as lenses. Moreover, groups #933, #142, #1046 and #1652 reveals high-energy γ-associations on Fermi/LAT 10-Year Point Source Catalog 4FGL-DR2 (4FGL J1144.9 + 1937, 4FGL J0152.2 + 3714, 4FGL J1230.8 + 1223 and 4FGL J1653.8 + 3945); and sources 4FGL J0123.1+3421, 4FGL J1259.5+2332, 4FGL J1353.2+3740 are located inside sizes of clusters #88, #1101 and #1242. Also several anomalies of spatial dynamic of galaxies in these clusters were separated. Joint observations of such clusters by orbital gamma-ray observatories with high angular resolution and ground-based Cherenkov air-shower experiments could possibly clarify the type of gravitational lensing and processes of particle acceleration in these objects especially highest energy of emitted gammas. Thus we propose including these and similar clusters in the programs of observations of the planned experiment GAMMA-400 (Gamma Astronomical Multifunctional Modular Apparatus) with angular resolution ~0.01° at Eγ = 100 GeV. Also now it is discussed coordination of multiwavelength observations program of Cherenkov Telescope Array (CTA) and GAMMA-400 objects list for observations. Moreover, common observations of such clusters by orbital gamma-ray telescopes with high angular resolution and ground-based Cherenkov air-shower experiments could possibly clarify the type of gravitational lenses.
Analysis of the 28Si(α,α)28Si elastic scattering at energies from 12.7 to 50.5 MeV
Authors: Amer Ahmed Hammad , Penionzhkevich Yu. E. , Yergaliuly G.
Published: December 2020

The available experimental elastic scattering angular distributions data of α-particles on 28Si nucleus have been reanalyzed in the energy range from 12.7 to 50.5 MeV. The analysis performed within the context of optical model (OM) potential. In the framework of double-folding model (DFM), we created the real part of optical potential using a density dependent version BDM3Y1-Paris interaction model.
Improving the Precision of Calibrating a Large Low-background Proportional Counter
Authors: Petrenko O D , Gangapshev A M , Gavrilyuk Yu M , Kazalov V V , Kuzminov V V , Panasenko S I , Ratkevich S S , Tekueva D A
Published: December 2020

The study of low-yield effects requires not only good quality of the original data but also puts high requirements for their processing procedures to increase the efficiency of the selection of useful events. The exploiting of the large cylindrical proportional counter’s electrostatic topology allows improving the extrapolation of information about the primary ionization of a multipoint event. Long-term calibration measurements with an external 109Cd-source allowed the development of a new method for analyzing the pulse shape from a sizeable proportional counter. Optimized analysis of the current’s pulse shape from the electron cloud of primary ionization in the counter improved the resolution and energy calibration. As a result, the efficiency of selecting useful events was increased by 25%.
Review of two-phase emission detectors R&D (Dedicated to the memory of Prof. Boris A. Dolgoshein)
Authors: Bolozdynya A I
Published: December 2020

This review is dedicated to the 90th anniversary of the outstanding experimental physicist Boris Anatolyevich Dolgoshein, in whose laboratory exactly 50 years ago the first two-phase emission detector has been created. Today two-phase emission detectors found the best application in the most sensitive at the moment experiments searching for cold dark matter in the form of weakly interacting massive particles (WIMPs). Multi-ton active mass WIMP detectors of the upcoming G3 generation shall become sensitive to solar neutrinos interactions, to double-beta decay of isotopes containing in the working media with naturally occurring isotope abundances. The RED-100 detector constructed at NRNU MEPhI will be used for investigation of the reactor neutrino elastic coherent scattering off xenon nuclei at the Kalinin NPP in 2021. ProtoDUNE-DP prototype emission detector (6x6x6 m3 300 tons LAr) is currently being assembled at the CERN Neutrino Platform in support of the DUNE project focused on investigation of high energy neutrino oscillations. Thus the detector technology invented at MEPhI 50 years has demonstrated a great potential to be used in a variety of fundamental research programs.
Separation of signals from neutrons and gamma quanta by the method of normalized signals
Authors: Kirsanov M A , Klimanov S G , Nazarov I V , Chepurnov A S , Kubankin A S
Published: December 2020

The solution of the problem how to register fast neutrons in the presence of intense gamma radiation is required when solving such fundamental and applied problems as registration of the neutron and gamma background in underground low-background experiments (the low background detectors of the neutrino and dark matter); beam diagnostic at particle accelerators; radiation monitoring at nuclear facilities, nuclear medicine; environmental monitoring. To separate signals from neutrons and gamma quanta, scintillation detectors with organic scintillators are used. The best scintillators are organic crystals of stilbene and p-terphenyl. The efficiency of separating signals from neutrons and gamma quanta can be increased using various methods of digital signal processing of the pulse shapes of the registered signals. A parameter traditionally called the Figure of Merit (FOM) is used to compare these methods. The experimental setup consisted of a Pu-Be neutron source, a scintillation detector with organic crystal p-terphenyl, a Hamamatsu R6094 photomultiplier, a CAEN DT5730 Digitizer (500 MHz, 14bit), which store the shape of each pulse for the following digital processing. A new “method of normalized signals” was developed. Three variants of the new method of normalized signals are described, which give the following FOM values: 1.6, 1.7, and 2.1. The traditional method of signals separation on the same array of experimental data showed the efficiency FOM = 1.6. The new method of signal separation is used to register fast neutrons in the installation dedicated for the development of a compact neutron generator, which is necessary for the calibration of low-background detectors of neutrinos and dark matter particles.
Quality control of MPD electromagnetic calorimeter modules
Authors: Durum A , Britvich G , Denisov A , Chernichenko S , Kostin M , Sukhikh A , Yanovich A , Krechetov Yu , Semenov A Yu , Vlasov N
Published: December 2020

The Multi-Purpose Detector (MPD) is constructing to study the properties of the hot and dense matter created in heavy-ion collisions in the energy range of 4-11 A*GeV where the maximum baryonic density is expected. The crucial detector in the new experimental setup is a large-sized barrel electromagnetic calorimeter (ECal), designed for precise spatial and energy measurements for photons and electrons. Taking into account the requirements of high energy resolution, dense active medium with the small Moliere radius, and high segmentation of ECal, the Shashlyk-type electromagnetic calorimeter with projective geometry has been selected. The mass production of ECal modules has been started. In this talk, we report about methods and technologies for the quality control of ECal modules and their components.
Feasibility studies for the measurement of single-spin asymmetry in inclusive K0
s production at pion beam at U-70
Authors: Kalugin N K , Mochalov V V , Moiseev V V , Morozov D A , Nurusheva M B , Rykov V L , Semenov P A , Vasiliev A N
Published: December 2020

In the Spring 2018, the first physics data was accumulated in the new SPASCHARM experiment at U-70 accelerator of IHEP, Protvino. The first stage of SPASCHARM’s physics programs prursues the goal of studying spin effects in the beam fragmentation region at an unpolarized negative 28 GeV beam, interacting with a frozen polarized proton target. In this resport, the feasibility of measuring the single spin asymmetry AN
in the reaction: π
− + p↑→K
0

S
+ X is evaluated by Monte-Carlo simulations. We present estimates of the detection efficiency as well as for expected event statistics. It is shown that, in the process of interest above, the attainable statistical errors for AN
would be at the scale of a few percents.
Kaons and Antikaons in Multi-Phase Transport Model
Authors: Chahal Nisha , Dutt Suneel , Kumar Arvind
Published: December 2020

We investigate the impact of medium modifications of kaons and antikaons on there rapidity distribution and production ratio using A Multi-Phase transport (AMPT) model. The medium modified masses of kaons and antikaons, which are used as input in AMPT model, are calculated using the chiral SU(3) mean field model. Usually in chiral SU(3) models along with the Weinberg Tomozawa term, the contribution of explicit symmetry breaking term and three range terms are considered to evaluate in-medium masses of kaons and antikaons. In the present work, we have considerd Weinberg Tomozawa term and two range terms to study their impact on the above listed experimental observables. The repulsive contribution to the mass of K
+ meson from the Weinberg term dominates over the attractive contribution from two range terms. For the K
− meson Weinberg term as well as two range terms give attractive contribution. Considering all these features from chiral effective model on properties of K
+ and K
− mesons, we explore the rapidity distributions of kaons and antikaons.
Energy levels of three particle muonic ions (μeLi), (μeBe), (μeB)
Authors: Eskin A V , Korobov V I , Martynenko A P , Sorokin V V
Published: December 2020

We calculate the electron Lamb shift (2P-2S) and the electron energy interval (2S-1S) in muonic Coulomb three particle systems (μeLi), (μeBe), (μeB) on the basis of variational method. Basic relativistic corrections, corrections to the vacuum polarization and nuclear structure are taken into account by the perturbation theory. The obtained numerical results can be used for a comparison with future experimental data.
Energy interval 2S-1S in muonic ions of lithium, beryllium and boron
Authors: Dorokhov A E , Faustov R N , Martynenko A P , Martynenko F A
Published: December 2020

Within the framework of the quasipotential method in quantum electrodynamics, the energy interval (2S – 1S) in muonic ions of lithium, beryllium and boron is calculated. Corrections of order α
3 – α
6, which are determined by relativistic effects, effects of vacuum polarization, nuclear structure and recoil, as well as combined corrections, including the above, are taken into account. Nuclear structure effects are expressed in terms of the nuclear charge radius in the case of one-photon interaction and the electromagnetic form factors of nuclei in the case of two-photon interaction. The obtained numerical values for the (2S – 1S) energy interval can be used for comparison with future experimental data and for a more accurate determination of the nuclear charge radii.
Vector mesons spectrum in a medium with a chiral imbalance induced by the vacuum of fermions
Authors: Kovalenko V , Andrianov A , Andrianov V
Published: December 2020

The properties of the light vector mesons in the presence of local parity breaking medium with a chiral imbalance are considered in the vector-meson dominance model. Applying the finite lowest-order radiatively induced local effective Lagrangian, initially developed for the QED, for the vector ρ and ω mesons, we obtained the mass spectrum as a function of momentum and chiral chemical potential μ5. We showed that in addition to the Chern–Simons term, splitting the transverse polarisations of the mesons, there is another radiatively induced contribution that becomes important at momentum and μ
5 around a few hundred MeV.
Shear viscosity of nucleons and pions in heavy-ion collisions at energies of NICA
Authors: Zabrodin E , Teslyk M , Vitiuk O , Bravina L
Published: December 2020

The shear viscosity is calculated microscopically via the Green-Kubo relation for the series of snapshots in the central region in an ongoing relativistic collision simulated via the UrQMD framework for various bombarding energies in the anticipated NICA experiments. In previous works the shear viscosity was calculated as function of temperature, while the chemical potential of baryon charge was kept constant. In present work we extract, in various time windows, the average energy density, the net baryon density and the small though nonzero net strangeness density. By fitting these parameters to statistical model, one can get temperature and both chemical potentials of baryon charge and strangeness. Simultaneously, these parameters are used as input to simulations in a box, again within the UrQMD transport model. The autocorrelations in time of the energy stress tensor are extracted, and subsequently via the Green-Kubo identities the shear viscosity coefficient of that equilibrium hadronic system is obtained. Then we calculate partial viscosity both for nucleons and pions for five collision energies from Elab
= 5 to 40 AGeV. It appears that substantial part of the contribution to total shear viscosity of the system comes out from pion-nucleon and other correlators.
Influence of quark content and collision geometry on proton production in heavy ion collisions
Authors: Larionova D , Berdnikov A , Berdnikov Ya , Kotov D , Mitrankov Iu
Published: December 2020

Proton production have been preivously measured in PHENIX experiment in Au+Au collisions at

s

N
N

=
200

GeV

. It was obtained that protons yields are enhanced over all mesons yields. This phenomenon was called “baryon puzzle”. This paper presents mesurements of protons in asymmetric Cu+Au collisions at

s

N
N

=
200

GeV

in order to investigate influence of collision geometry. Results in Cu+Au and Au+Au systems were found to be in agreement at similar number of participants, which might indicate that proton production in heavy-ion collision scales with the average size of the nuclear overlap region and do not depends on the details of its shape. ln order to investigate influence of quark content on production of protons consisting of three quarks comparison with φ, π
0 -mesons (quark-antiquark pairs) was provided in Cu+Au collisions at the collision energy of 200 GeV. Such information can improve our understanding of quark-gluon plasma and recombination model.
12 years of HYDJET++ generator: history and the latest results
Authors: Belyaev A V , Bravina L V , Chernyshov A S , Eyyubova G Kh , Korotkikh V L , Lokhtin I P , Malinina L V , Petrushanko S V , Snigirev A M , Zabrodin E E
Published: December 2020

It has been dozen years since HYDJET++ Monte-Carlo event generator for the simulation of relativistic heavy ion collisions was developed. Now the generator is widely used for the simulation of nucleus-nucleus interactions from NICA to LHC energies. The model calculations on soft and hard probes of quark-gluon plasma (including collective flow, different kinds of particle correlations, jets, D and B mesons etc.) agree well with the experimental data. In this paper the selected main results and the very new ones are presented.
Reconstruction of moments of particle distributions with Identity Method at MPD
Authors: Altsybeev Igor , Petrov Vitaliy
Published: December 2020

Precise determination of the moments of multiplicity distributions of identified particles could be challenging due to the misidentification in detectors. The so-called Identity Method allows one to solve this problem. In this contribution, performance of the Identity Method was tested on the A – A events simulated in the conditions of the MPD experiment at NICA. With this method, moments within a single kinematic window as well as coefficients of forward-backward pseudorapidity correlations are extracted.
Stopping of protons in pA collisions at SPS and NICA energies in analytical hydrodynamic model and in SMASH event generator
Authors: Ermakova V , Sandul V , Feofilov G
Published: December 2020

Our study is motivated by the first experimental results on pion production and stopping obtained in pA collisions in E910 experiment at BNL. The effect of stopping is the deceleration of an incident high energy proton traversing the target nucleus. It appears due to the energy losses relevant to the production of secondary particles in the inelastic interactions with nucleons.

A hydrodynamic effective model of stopping is proposed that is based on the consideration of the nuclear matter as a liquid and by the introduction of an effective stopping force acting on a fast-moving proton. With this force, we obtain a differential equation that describes the relativistic motion of a proton in a nucleus. Calculations in the framework of this analytical model are performed for the correlation between the mean multiplicity of charged pions and a number of binary collisions.
Resolving Black Hole Information Paradox: Revisited
Authors: Kashi B
Published: December 2020

Blackhole remnants are one of the most exotic remnants in our universe, leaving behind several unsolved paradoxes. Resolving the black hole information paradox, in particular, can direct us to numerous engrossing discoveries and provide a decent understanding of the unsolved conventional theories. We readdress the notions underlying the paradox explicitly, beginning from the basic principles. Various theories, explanations, conclusions, their advantages and disadvantages in several works of literature regarding the information paradox and black hole entropy are discussed. Recent developments in the interpretation of the black hole information paradox are reviewed. A congenital solution to this contradiction involves the transition of classical physics to quantum physics. At the centre of the black hole, the space-time theory by Einstein’s general theory of relativity fails. The research suggests that the solution obtained from considering the principles of quantum gravity is quite plausible. This approach also gives a decent explanation towards the recondite hypothesis of tunnelling of black holes to white holes and the interior geometries of white holes.
Δϕ distributions between final state particles as a criterion of the pile-up background mismodeling and its impact on Z(vv)γ process
Authors: Pyatiizbyantseva D , Soldatov E Yu
Published: December 2020

In the case of the pile-up background (background from the neighboring interactions inside the bunch crossing) for Z(vv)γ process at the Large Hadron Collider (LHC) experiments, its accurate calculation is very challenging. If the impact of the pile-up background is negligible, as it is expected in the case of Z(vv)γ process selection, some global uncertainty from this source can be used. This report studies the pile-up background and shows that it is expected to have a completely different shape for Δϕ distributions between final state particles in comparison to the signal and other background processes. Thus, the absence of Δϕ-mismodeling in the analysis proves that the pile-up background is indeed negligible.
Application of Authentication and Secret-key Distribution Mechanism of Challenge-response in Micro-service Security Supervision and Authentication Interaction
Authors: Chunlei Chang , Liang Bai , Kai Yun , Kai Li
Published: December 2020

The aims are to ensure the safety of communication among micro-service system modules, protect the trust of inter-servant-module, and improve the communicating efficiency. The authentication and secret-key distribution mechanism of challenge-response are introduced to improve the scheme for secure communication, supervision, and forewarning of data, and the effect is then tested. The modules of authentication and secret-key distribution and the data security communication are built according to the characteristic of challenge-response. These modules orient micro-service secure communication protocol. Besides, supervision and forewarning scheme is improved by running the log. Next, the security and efficiency of communication encryption and the function of supervision and management are tested. The results indicate that the scheme proposed can ensure the confidentiality and integrity of the communication process, and the log analysis module designed can promote and guarantee the daily operation and maintenance of administrators. Such progress has important reference value for applying authentication and secret-key distribution mechanism of challenge-response in micro-service security supervision and authentication interaction.
Brief Analysis of perfecting the law of maintaining computer network security
Authors: Huang Mei , Gu Liangjun
Published: December 2020

Since the 21st century, computer network technology has developed rapidly, and now all industries are inseparable from the application of computer network technology. However, due to the complexity and virtuality of computer network itself, it is easy to cause some network security problems. In addition, due to the rapid development of computer network, some laws related to computer network security have not been updated and improved in time, and the application of laws to maintain computer network security is also facing some great difficulties. Therefore, it is necessary to strengthen the establishment and improvement of laws and regulations on computer network security and build a peaceful, safe, open, cooperative and orderly cyberspace.
Application of Computer Accounting System in Internal Control of Enterprise Accounting
Authors: Lan Yulin , Tang Yueting
Published: December 2020

In the process of rapid development of computer technology, to promote the effective application of corporate accounting internal control in computers, accounting information system software can be constructed. The use of computer accounting information system software can improve the efficiency and level of corporate internal accounting control. The system software can not only improve the corporate financial management system, but also protect the accounting information system of the calculation class. When carrying out the internal control of the computer accounting information system, we need to strengthen computer hardware and software protection, and correctly face the security threats that exist in the computer for accounting control. In addition, we also need to take effective measures to improve the application level of corporate internal control on computers.
Reducts in single valued neutrosophic ß-covering approximation spaces
Authors: Mao Lingling
Published: December 2020

The problem of reducts is an interesting issue in all rough set models. In this paper, we propose the concept of the reduct in a single valued neutrosophic β-covering approximation space (SVN-β-CAS). Moreover, reducts in SVN-β-CASs are investigated while adding and removing some objects of the universe, respectively. Firstly, the notion of the reduct in a SVN-β-CAS is presented. It can be seen as the generalization of the reduct in covering and fuzzy β-covering approximation spaces. Then, two new SVN-β-CASs are presented while adding and removing some objects of the original universe. Finally, some properties of reducts of SVN β-coverings are investigated while adding and removing some objects, respectively.
The Research And Application Of Intelligence Evaluation System In colleges and universities
Authors: Qu Feng Lin , Chen Lin , Jiang YongChen
Published: December 2020

Teaching quality is the lifeline and core competitiveness of the survival and development of higher vocational colleges. Student evaluation plays an important role in the monitoring of teaching quality. Based on the analysis of the existing teaching evaluation system and its results, this paper proposes a multi-dimensional teaching evaluation information system based on quantitative teaching evaluation index system and intelligent analysis function. The system has been tested and run by a university, and its feasibility and effectiveness have been verified. It provides a reference scheme for other universities to build a multi-dimensional evaluation system based on the characteristics of the subject.
BSMM: A Broadcast Storm Mitigation Model Based On Distributed Data Clusters and Hybrid Network Architecture in Vehicular Named Data Network
Authors: Fan Na , Li Chen , Zhang Tianyang , Duan Zongtao , Wang Qinglong , Zhu Yishui
Published: December 2020

Vehicle networks play a key role in intelligent traffic field. Named Data Networks (NDN) which has characteristics of interest packet driving and content caching is suitable for Vehicle networks. After the technology of NDN is used in vehicle networks, Vehicular Named-data Network (VNDN) is constructed. However, the efficiency of communication is affected by the high-speed movement of vehicles and the changing topology of VNDN. In VNDN, vehicles broadcast interest packets to retrieve required data. It is easier to rise broadcast storm because of the broadcast behaviour. In order to deal with this problem, we firstly propose a hierarchical hybrid network architecture which is consisting of vehicle network and infrastructure network. Secondly, we propose a concept of distributed data named cluster based on the hybrid network architecture. Based on the above, a novel broadcast storm mitigation strategy (BSMS) which includes a real-time route update algorithm and a hierarchical routing request algorithm is proposed to relieve the broadcast storm. At the same time, the proposed model based on distributed data named clusters provides a real-time update data request interface for vehicles. The simulation results show that the proposed model BSMM is able to resist the broadcast storm and improve the efficiency of communication among vehicles in VNDN.
Activity recommendations based on heterogeneous social networks
Authors: Qi Xiaoying , Yu Wen
Published: December 2020

EBSN (event-based Social Network) is a Heterogeneous Network, namely, H-EBSN (Heterogeneous event-based Social Network), which contains both online interactive information and offline interactive information. How to effectively use the interaction between online and offline to recommend activities is one of the hot issues at present. The following work has been done for the activity recommendation of H-EBSN:

(1) Construct H-EBSN, extract all link-roads and obtain user interest through link-roads’ characteristics.

(2) Analyze H-EBSN meta path, take the path number of extracted link-roads as feature vector, establish user interest model, and use generalized regression neural network to solve the model.

(3) The training set was constructed by using the movie-watching activity data set, and the generalized regression neural network was used to solve the model. Experiments show that the activity recommendation method based on H-EBSN proposed in this paper has a good recommendation effect.
Target recognition algorithm based on improved depth separable convolution
Authors: Shi Jun , Liu Yunqing , Liu Quanyang , Zhang Qiong , Fei Yan
Published: December 2020

Realizing accurate target recognition in the fields of drones, vehicle-mounted systems, robots, etc. has increasingly become a hot research direction for researchers. Aiming at the problem of using deep learning algorithms to identify targets on mobile devices with limited size, the network model has a large number of parameters resulting in a large calculation cost, a complicated recognition process, and a large number of iterations resulting in a long recognition time. This paper proposes an improved deep separable convolution algorithm, which consists of deep convolution and point-by-point convolution, which is based on convolution kernels for step-by-step filtering and combination. After deep convolution, batchnorm is added, and the activation function uses a linear function. Add batchnorm and nonlinear activation function ReLU after 1×1 convolution to ensure the accuracy of target detection. This algorithm reduces the amount of parameters while ensuring recognition accuracy, reduces the amount of recognition calculations, and reduces the weight of the network model. It provides a network foundation for implementing image recognition on devices with limited size.
Artificial Intelligence in Agriculture
Authors: Zha Jiali
Published: December 2020

The application of AI in agriculture has been widely considered as one of the most viable solutions to address food inadequacy and to adapt to the need of a growing population. This review provides an overview of AI’s application in agronomic areas and progress in research labs. The review first presents two fields that AI can potentially play an important role in, which are soil management and weed management, and then Internet of Things (IoT) a technology that shows great potential in future usage is mentioned. Three challenges that need to be addressed in order for AI-based technology to be popularized in markets are uneven distribution of mechanization, the ability of algorithms to process large sets of data accurately and quickly, and the security and privacy of data, as well as the devices. Agricultural robots targeted at diverse aspects in agricultural industry have been developed and improved greatly in the past years, and although pointing out the hardship of applying machines and algorithms tested in experimental environment to real environments, the review highlights an already prosperous development and a promising prospect of application.
Study on the Application of CALL in College Oral English Language Teaching
Authors: Dang Ruihong
Published: December 2020

For a long time, Computer-aided language Leaching(CALL) system has been widely used in College English teaching practice. With the deepening of education informatization reform, how to use CALL to improve college oral English teaching has become a hot research topic. Therefore, this paper analyzes the characteristics of the application of CALL in oral English teaching, and puts forward some improving strategies and optimizing measures under the background of education informatization, aiming to enhance the role of CALL system in oral English teaching, so as to improve the teaching effect and teaching quality of college oral English
Research on the Innovation of Artificial Intelligence Training Mode for New Engineering Majors in Higher Vocational Colleges
Authors: Li Gan
Published: December 2020

The “new” of the new economy is mainly reflected in two aspects. First, information technology (including cloud computing, big data, Internet of things, artificial intelligence and other technologies) is widely used in social material production and spiritual and cultural fields. The new form of social culture and material production has the characteristics of high efficiency, changeability and cross field. Second, the wide application of new materials and bioengineering technology will greatly change the relationship between man and nature (including the material characteristics of human beings), and make the living state and living space of human beings have essential changes different from those of any previous era. With the prosperity of China’s industrial manufacturing industry, the industrial chain of artificial intelligence is developing rapidly. The purpose of AI interface research is to realize human-computer communication. Therefore, scholars must make efforts from both theoretical and practical aspects to solve the functional problems of computer’s understanding and translation of words and languages, and self-expression. [1] Due to the research and application of intelligent interface technology, the development of computer technology has been greatly promoted, and the operation speed and human-computer communication have been greatly improved.
Detection and Analysis of Credit Card Application Fraud Using Machine Learning Algorithms
Authors: Han Yaodong , Yao Shun , Wen Tie , Tian Zhenyu , Wang Changyu , Gu Zheyuan
Published: December 2020

Fraud is a widespread problem in the financial industry with devastating effects. It is essential to prevent and reduce fraud effectively. Traditional approaches, such as expert system, suffers from the incapability to handle complex problems and tremendous amount of data, while the recent development of various machine learning techniques brings new solutions. With many research works focusing on tackle frauds of credit card transaction or insurance, only few mentioned the identity fraud of credit card application. This article presents a few machine learning models to detect such fraud. We firstly explore and clean up the data. Then 331 expert variables are created with professional consult and selected to 30 to reduce dimensionality of our data. Multiple models, such as logistic regression and decision trees, are built and fit on the training set. Finally, we found that the random forest model performs the best in terms of fraud detection rate, achieving 54% in out-of-time test. The obtained model can be applied in anti-fraud monitoring systems, or a similar model development process can be performed in related business areas to detect fraud and reduce the occurrence of such behaviors.
Research on COVID-19 Global Forecast based on SIR Model-ML regression
Authors: Wei He , Qingtao Zeng , Likun Lu , Yeli Li
Published: December 2020

Under the background of the global COVID-19 pandemic, the global COVID-19 epidemic spread was modeled and analyzed, and its future trend was predicted. The dataset covers 163 countries and almost 2 full months from 2020, which is enough data to get some clues about the pandemic. The epidemic situation was predicted by the fusion of SIR model and ML regression, and the results showed that the model analysis was basically consistent with the real performance of the epidemic development. Finally, the development stage and trend of the epidemic situation are evaluated to provide a basis for the government to formulate relevant epidemic prevention policies.
Short text classification based on bidirectional TCN and attention mechanism
Authors: Zuo Ying , Jiang Lifen , Sun Huazhi , Ma Chunmei , Liang Yan , Nie Shuaibao , Zhou Yongheng
Published: December 2020

The context-related semantic information of the text in the traditional short text classification algorithms are not fully captured, a text classification model based on bidirectional temporal convolutional network and attention mechanism (BTCA) was proposed. Multi-layer dilated convolution was used to increase the receptive field and better capture long distance dependent information. At the same time, attention mechanism was used to increase the attention to the local key feature in the text, and the bidirectional temporal convolution network was used to extract contextual multi-scale semantic information to enrich semantics, the problem of sparse short text features was solved to a certain extent, and text classification effect was improved. The public corpus of the THUCNews was used to conduct a comparative experiment. It is pointed out that effect of short text classification is improved by using BTCA model, with an accuracy rate of 91.47%, which is better than commonly used models.