bluuebunny/crossref_metadata_2025 huggingface dataset:
High temperature magnetic characterisation of structural steels using Epstein frame
Authors: Wilson John W , Zhou Lei , Davis Claire L , Peyton Anthony J
Published: July 2021

Electromagnetic non-destructive testing techniques provide an attractive solution to the problem of monitoring microstructural changes in steels undergoing heat treatment as they are non-contact, have a short response time and are relatively inexpensive. However, to take full advantage of these techniques it is necessary to be able accurately measure the magnetisation characteristics of the materials of interest at temperatures up to the Curie point. This paper details the development of a novel high temperature Epstein frame for installation in a furnace with the design informed and results validated by finite element modelling. Hysteresis loop characteristics are successfully measured for a dual phase steel up to the Curie point for heating and cooling. Results show the developed system has the potential to provide valuable data to inform online electromagnetic monitoring systems.
Mechanical studies of the solid electrolyte interphase on anodes in lithium and lithium ion batteries
Authors: McBrayer Josefine D , Apblett Christopher A , Harrison Katharine L , Fenton Kyle R , Minteer Shelley D
Published: July 2021

A stable solid electrolyte interphase (SEI) layer is key to high performing lithium ion and lithium metal batteries for metrics such as calendar and cycle life. The SEI must be mechanically robust to withstand large volumetric changes in anode materials such as lithium and silicon, so understanding the mechanical properties and behavior of the SEI is essential for the rational design of artificial SEI and anode form factors. The mechanical properties and mechanical failure of the SEI are challenging to study, because the SEI is thin at only ~10–200 nm thick and is air sensitive. Furthermore, the SEI changes as a function of electrode material, electrolyte and additives, temperature, potential, and formation protocols. A variety of in situ and ex situ techniques have been used to study the mechanics of the SEI on a variety of lithium ion battery anode candidates; however, there has not been a succinct review of the findings thus far. Because of the difficulty of isolating the true SEI and its mechanical properties, there have been a limited number of studies that can fully de-convolute the SEI from the anode it forms on. A review of past research will be helpful for culminating current knowledge and helping to inspire new innovations to better quantify and understand the mechanical behavior of the SEI. This review will summarize the different experimental and theoretical techniques used to study the mechanics of SEI on common lithium battery anodes and their strengths and weaknesses.
Single-step reactive ion etching process for device integration of hafnium-zirconium-oxide (HZO)/titanium nitride (TiN) stacks
Authors: Mauersberger Tom , Trommer Jens , Sharma Saurabh , Knaut Martin , Pohl Darius , Rellinghaus Bernd , Mikolajick Thomas , Heinzig André
Published: July 2021

The integration of new materials such as high-k dielectrics or metals into advanced CMOS gate stacks has led to major developments in plasma etching. The authors present a study which is dedicated to the etching of amorphous hafnium zirconium oxide (HZO) and titanium nitride (TiN) layers with Ar/Cl2 chemistry in one single step. By adjusting the gas ratio and the inductively coupled plasma power, the etching process is shown to have a slow and well controllable etch rate for HZO and TiN. Additionally, a high selectivity between both materials and SiO2 can be achieved. Gate stack etching was successfully demonstrated and transmission electron microscopy-images revealed good anisotropic etching for HZO and TiN with an etch stop in SiO2 without damaging the silicon underneath. The process is further applied for the fabrication of metal-ferroelectric-metal capacitors, here TiN-HZO-TiN, and the feasibility of the chosen material combination is proven by electrical characterization. The strategy of using low temperature plasma-enhanced atomic layer deposition for TiN-deposition and forming gas anneal after structuring leads to high remanent polarization-values.
Channel discord and distortion
Authors: Zhang Wei-Wei , Sanders Yuval R. , Sanders Barry C.
Published: July 2021

Discord, originally notable as a signature of bipartite quantum correlation, in fact can be nonzero classically, i.e. arising from noisy measurements by one of the two parties. Here we redefine classical discord to quantify channel distortion, in contrast to the previous restriction of classical discord to a state, and we then show a monotonic relationship between classical (channel) discord and channel distortion. We show that classical discord is equivalent to (doubly stochastic) channel distortion by numerically discovering a monotonic relation between discord and total-variation distance for a bipartite protocol with one party having a noiseless channel and the other party having a noisy channel. Our numerical method includes randomly generating doubly stochastic matrices for noisy channels and averaging over a uniform measure of input messages. Connecting discord with distortion establishes discord as a signature of classical, not quantum, channel distortion.
Overview of the FTU results
Authors: Pucella G. , Alessi E. , Almaviva S. , Angelini B. , Apicella M.L. , Apruzzese G. , Aquilini M. , Artaserse G. , Baiocchi B. , Baruzzo M. , Belli F. , Bin W. , Bombarda F. , Boncagni L. , Briguglio S. , Bruschi A. , Buratti P. , Calabrò G. , Cappelli M. , Cardinali A. , Carlevaro N. , Carnevale D. , Carraro L. , Castaldo C. , Causa F. , Cavazzana R. , Ceccuzzi S. , Cefali P. , Centioli C. , Cesario R. , Cesaroni S. , Cianfarani C. , Ciotti M. , Claps G. , Cordella F. , Crisanti F. , Damizia Y. , D’Arcangelo O. , De Angeli M. , Di Ferdinando E. , Di Giovenale S. , Di Troia C. , Dodaro A. , Esposito B. , Falessi M. , Fanale F. , Farina D. , Figini L. , Fogaccia G. , Frigione D. , Fusco V. , Gabellieri L. , Gallerano G. , Garavaglia S. , Ghillardi G. , Giacomi G. , Giovannozzi E. , Gittini G. , Granucci G. , Grosso G. , Grosso L.A. , Iafrati M. , Laguardia L. , Lazzaro E. , Liuzza D. , Lontano M. , Maddaluno G. , Magagnino S. , Marinucci M. , Marocco D. , Mazzitelli G. , Mazzotta C. , Meineri C. , Mellera V. , Mezzacappa M. , Milovanov A. , Minelli D. , Mirizzi F.C. , Montani G. , Moro A. , Napoli F. , Nowak S. , Orsitto F.P. , Pacella D. , Pallotta F. , Palomba S. , Panaccione L. , Pensa A. , Pericoli-Ridolfini V. , Petrolini P. , Piergotti V. , Piron C. , Pizzuto A. , Podda S. , Puiatti M.E. , Ramogida G. , Raspante B. , Ravera G. , Ricci D. , Rispoli N. , Rocchi G. , Romano A. , Rubino G. , Rueca S. , Scisciò M. , Senni L. , Sibio A. , Simonetto A. , Sozzi C. , Tartari U. , Taschin A. , Tilia B. , Trentuno G. , Tuccillo A.A. , Tudisco O. , Tulli R. , Valisa M. , Vellucci M. , Viola B. , Vitale E. , Vlad G. , Zannetti D. , Zaniol B. , Zerbini M. , Zonca F. , Zotta V.K. , Angelone M. , Barcellona C. , Calacci L. , Caneve L. , Colao F. , Coppi B. , Galeani S. , Galperti C. , Gasior P. , Gromelski W. , Hoppe M. , Kubkowska M. , Lazic V. , Lehnen M. , Marinelli M. , Martinelli F. , Milani E. , Mosetti P. , Muscente P. , Nardon E. , Passeri M. , Reale A. , Sassano M. , Selce A. , Verona C. , Verona-Rinati G.
Published: July 2021

Since the 2018 IAEA FEC Conference, FTU operations have been devoted to several experiments covering a large range of topics, from the investigation of the behaviour of a liquid tin limiter to the runaway electrons mitigation and control and to the stabilization of tearing modes by electron cyclotron heating and by pellet injection. Other experiments have involved the spectroscopy of heavy metal ions, the electron density peaking in helium doped plasmas, the electron cyclotron assisted start-up and the electron temperature measurements in high temperature plasmas. The effectiveness of the laser induced breakdown spectroscopy system has been demonstrated and the new capabilities of the runaway electron imaging spectrometry system for in-flight runaways studies have been explored. Finally, a high resolution saddle coil array for MHD analysis and UV and SXR diamond detectors have been successfully tested on different plasma scenarios.
Biosynthesis of CuO NPs and its anticancer activity on human colon cancer cell lines (HT-29)
Authors: obaid Maithm A. , Harbi Khalid Hellal , Abd Ahmed N.
Published: July 2021

The environmentally friendly syntheses of the nanoparticles through the green way from the extracts of the plants has proven itself in the field of modern sciences, with improved drug efficiency and less toxicity. The study groups in the have bio-synthesized cost-effective and stable copper oxide nano-particles (CuONPs) from plant leaves (i.e. the Turmeric). A variety of the analytical approaches, like the UV-Visible Spectroscopy (UV-Vis), Fourier-Transformation Infra-red Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD), have been utilized for the confirmation of the syntheses of the crystalline CuONPs from the extract of the turmeric leaves (SEM), Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED) pattern. Synthesized CuONPs have been tested as well for the anti-cancer activity with the use of the MTT (3- (4,5dimethyl-2tiazolyl)-2,5-diphenyl-2tetrazolium bromide) assay on the cell lines of the human colon cancer (HT29). The results have shown that the synthesized CuONPs had a high anti-cancer cytotoxicity on the cell lines of the human colon cancer (HT-29) with an IC-50 value of 40 g mL-1, which was briefly addressed in the present paper.
Phase transition of RN-ERN coupled network in failure recovery process
Authors: Fu Cong , Li Xiaoyan , Zhao Hui , Chen Yuguang
Published: July 2021

We simulate the failure recovery process and study the phase transition from high network activity (HNA) state to low network activity (LNA) state of the coupled network consisting of a regular network (RN) and an Erdos-Rényi network (ERN). Two recovery mechanisms are considered, the internal recovery and the external recovery, in the failure recovery process. We find that the evolution of the coupled network is crucially dependent on the coupling strength c between the two subnetworks and the external recovery possibility r since RN is sensitive to external recovery. A weak coupling can drive coevolution of the subnetworks when r ≈ 1.0, while the synchronous HNA-LNA phase transition needs stronger coupling to occur when r is smaller. The internal recovery enhances the robustness of network which makes coevolution more difficult to take place.
Study on improving efficiency of a plasma synthetic jet through dynamic pressure supplemental air
Authors: Liu Rubing , Chen Yueshi , Mei Xiaoyin , Lin Qi , Zeng Yixuan
Published: July 2021

To improve efficiency of a plasma synthetic jet (PSJ) under the high frequency actuation mode we investigated the effect of the pressure of supplemental air on efficiency of a PSJ actuator. First, the analytic model of the air supplement PSJ is established to analysis the effect of the air supplement pressure on the jet velocity of the PSJ. The theory analysis shows that the jet peck velocity and average velocity is increased dramatically. Furthermore, to reflect the efficiency performance of a PSJ in such mode, the average transform efficiency of the energy is used as an index which is calculated by the measured average jet speed and average discharging power consumption. The results show that the discharging parameters fluctuate dramatic in different actuation cycles in the high frequency actuation mode. And the average transform efficiency can be used to evaluate the efficiency in such mode. As the pressure of supplemental air increase, the average discharging power consumption decrease by up to 45.3% while the jet enhancement rate remains above 9% constantly. Overall the average transform efficiency is boosted by 1-2 orders of magnitude. The research reveals that the supplemental air can keep the gas discharging stable to improve the jet performance, and increase the efficiency of the PSJ.
Electronic transport through a silicene bilayer barrier
Authors: Shao Huaihua
Published: July 2021

We investigate the electronic transport properties of a finite-size silicene bilayer barrier. We got the boundary conditions at the interface of monolayer and bilayer silicene using the tight-binding model. By matching the wavefunctions, we got the transmission probability as a function of incident angle for several lengths of bilayer barrier and incident energys. We found that a clear resonant tunneling appears because of evanescent modes in bilayer silicene. We also calculate the conductance in a overlap configuration which displays an oscillatory behavior as increase of either incident energy or length of bilayer barrier.
Study of catecholate-functionalized zinc complex on carbon steel and its application to corrosion resistance
Authors: Che Xihong , Yuan Ronghui , Tang Licheng , Xiong Yudong , Wu Mengfan , Zhu Maihao
Published: July 2021

This work investigated the corrosion resistance of an acceptable composite coating obtained from catecholate-functionalized zinc complex (CFZ). The ion distribution states of catechol and Zn(II) at different pH values were calculated, and the anticorrosion of coatings on carbon steel by means of neutral salt spray test were specifically monitored. CFZ-steel was fabricated using 30 min electrodeposition of CFZ/Na2SO4 media at pH 9 on carbon steel. Lower corrosion degree of CFZ-steel in salt spray during oxidation process meant slight amount of corrosion attack on the steel surface. Also, the growth tendency of corrosion rate was gradually reduced, indicating a nonlinear relationship between corrosion rate and contact time. This indicated electrodeposition of CFZ was not only appropriate for the practical application of composite coatings to corrosion resistance but also a key step for extending the service life of carbon steel.
Anomalous transport on a corrugated ratchet potential
Authors: Mazzitello Karina Irma , Zarlenga Daniel Gustavo , Arizmendi Constancio Miguel
Published: July 2021

We present an extensive study the motion of particles in a rocking ratchet potential corrugated by quenched correlated disorder. The spatial disorder slows down the collective motion of particles. Anomalous transport in its both forms, subdiffusion and superdiffusion has been observed at long times. We provide a qualitative explanation for the origin of these anomalies. These behaviors are a direct consequence of the interplay between the ratchet potential roughness and the temperature of the system. In the same way as Khoury et al [1], we find a relation between the mean velocity of the particles and the different kinds of diffusion at long time.
A detailed study of mode II test specimen with elastic or plastic crack tips by using boundary element method
Authors: Young Lih-jier , Ouyang Lin , Wang Xiaofeng
Published: July 2021

In linear elastic fracture mechanics the stress and strain magnification at the crack tip is characterized by stress intensity factors which have been obtained for a large variety of loading and specimen geometries and of course mode II test specimen included. In this paper not only different kinds of boundary conditions of the contact surfaces of the elastic crack tip will be discussed but the plastic one. The rotation of the center line of the specimen will also be discussed. The results show the powerful application of the BEM model in the specimen.
Reynolds number dependency of small scale structures in steady anisotropic turbulence produced by implicit large-eddy simulation
Authors: Oshibuchi Mayuka , Suzuki Hiroki , Mochizuki Shinsuke
Published: July 2021

This study presents small-scale fluctuation characteristics of anisotropic steady turbulence reproduced by implicit large eddy simulation (LES). The Reynolds number dependence of this small-scale fluctuation characteristic is approached in this study. This study focuses on that, a small scale turbulence field is not needed to be isotropic if the Reynolds number is sufficiently high. The anisotropic steady turbulence is maintained steady by using the forcing terms in the governing equations. The results of the implicit LES are compared with those obtained by direct numerical simulation (DNS) and LES based on the Smagorinsky model. Spatial derivatives are discretized using a fourth-order central difference scheme that conserves the kinetic energy of the turbulence field. The governing equations are integrated for the temporal direction using the fourth-order Runge-Kutta method. The results of enstrophy and small-scale turbulence characteristics quantified by the isotropy parameter are found to be consistent between the implicit LES and DNS.
Thermo-mechanic coupled damage simulation of idealized concrete material
Authors: Su Juan , Jiang Yongsheng , Chen Cheng , Guo Guanqun
Published: July 2021

Several special concrete structures are subjected to temperature cycling environment. Temperature cycling will influence the physical and mechanical behaviours of concrete material. As the number of loops of temperature cycling increases, the mechanical performance of concrete will decrease. Two different multi-phase composite numerical models for concrete are herein introduced in this paper. Based on damage development and evolution in the mortar and interface transition zone of concrete under temperature cycling, the thermo-mechanic coupled multi-scale behaviours of different groups of concrete were simulated. Afterwards, the failure process and failure mode of concrete material in uniaxial stress state was studied. It is found that the damage within concrete material concentrates on the interface transition zone under temperature cycling, and will develop in mortar as the number of loops of temperature cycling increases. Finally, it is verified that temperature cycling will remarkably influence the internal stress distribution and failure mode of concrete structures. The research findings of the present paper are conducive to improving the mechanical properties of aggregate concrete by optimizing the mix proportion.
Study on one-way transmission of acoustic wave based on metasurface
Authors: Wang Houjiang , Lin Wei , Gu Jincheng
Published: July 2021

In this paper, using the characteristics of abnormal reflection metasurfaces that can produce different reflection angles, a method that can realize the one-way transmission of acoustic waves is designed, which is verified by simulation. And two different types of metasurface structures are used to verify the unidirectional transmission of acoustic waves. One is the acoustic impedance matching type metasurface, and the other is the geometric groove type metasurface. Based on the generalized Snell’s law, the principle of one-way transmission of sound waves is analyzed, and simulation is carried out by COMSOL multiphysics coupling simulation software, which verifies the theoretical analysis of one-way transmission of acoustic waves. The results of this study may have potential applications in architectural acoustics (such as noise control) and medicine (such as ultrasound therapy).
Time-series observation of the effects of kinetic energy conservation error on isotropic and anisotropic steady incompressible turbulence
Authors: Honda Ryoma , Suzuki Hiroki , Mochizuki Shinsuke
Published: July 2021

The purpose of this study was to examine the effects of kinetic energy conservation error on isotropic and anisotropic steady incompressible turbulence fields. Results were obtained from time series of turbulent kinetic energy and static pressure fluctuation. A standard large-eddy simulation (LES) was used in the numerical analysis. The conservation error was generated using the Crank-Nicolson method. The result obtained using the fourth-order Runge-Kutta method was used to set results of reference. The effects of the conservation error on the mean value of the global turbulent kinetic energy were found to be small. On the other hand, it was found that the time series and mean values of static pressure fluctuation root mean square (rms) were sensitive to the conservation error. This discrepancy in the static pressure fluctuation rms was able to be reduced by adjusting the value of the model constant used in the LES. However, this adjusted model constant caused an error in the global turbulent kinetic energy. These results were found in both isotropic and anisotropic turbulence fields.
Development of artificial compressibility method with elliptic relaxation approach
Authors: Rahman Md Mizanur , Alam Feroz , Zhu Zefei , Sadrul Islam AKM
Published: July 2021

An artificial compressibility (AC) method resorting to the pressure-based algorithm is developed on a non-orthogonal non-staggered grid using a cell-centered finite-volume Δ-approximation for incompressible fluid flow problems. A pressure time-derivative is used to perturb the equation of continuity. This artifact provokes a density preconditioning which transforms conservative variables to primitive ones; the physical relevance of density preconditioning signifies to convoke compatible linearizations of residuals in collaboration with an AC parameter. The avoidance of pressure-velocity decoupling is enhanced by a consistently formulated cell-face dissipation approach, preserving an increased accuracy with a greater flexibility analogous to the MUSCL (monotone upstream-centered schemes for conservation laws) approach. An elliptic-relaxation scheme having accountability to promoting anisotropic diffusion coefficients is applied to smooth out the pressure residual. Numerical experiments dictate that pertaining to the pseudo-time integration method, the overall contrivance is benefited with an enhanced robustness having sensible oscillation damping characteristics.
Finite-time stabilization for a first-order hyperbolic system with integral kernel by boundary control
Authors: Zeng Caijin , Zhou Zhongcheng
Published: July 2021

This paper consider the finite-time boundary stabilization for a first-order hyperbolic system with integral kernel and lower order term. Via choosing a suitable integral transformation converting the original system into a finite-time stable object system, then, we obtain the control law and certify the finite-time stabilization of the closed-loop system combined with the finite-time stability of object system and invertibility of forward transformation.
A discrete chicken swarm optimization for traveling salesman problem
Authors: Liu Yuanjie , Liu Qiang , Tang Zhi
Published: July 2021

Traveling Salesman Problem (TSP) is a typical combinatorial optimization problem, and it is a NP-hard problem. The total number of routes increases exponentially with the number of cities, so it is great significance to design an effective algorithm to find the optimal solution accurately. Chicken Swarm Optimization (CSO) is a new intelligent optimization algorithm, which is mainly proposed for continuous problems. It has the advantages of fast convergence speed and high convergence accuracy. This paper proposed a Discrete Chicken Swarm Optimization (DCSO) for TSP. The CSO is discretized by introducing the methods of swap, order crossover and reverse order mutation, where the search space of the solution is enlarged, and the diversity of the solution is increased. The typical TSP models are simulated and compared with the Basic Ant Colony Optimization and Genetic Algorithm to verify the feasibility of the presented method.
Enumeration formulas for standard young tableaux of approximate C shape
Authors: Li Qiuying , Li Feifei
Published: July 2021

This paper focuses on the combinatorial enumeration of the truncated hollow standard Young tableaux of approximate C shape. The enumeration formula of approximately C-shaped SYT, namely the convolution of Catalan numbers, is derived by using the multi-integral method based on the sequence statistical model. Meanwhile, it is found that the first and last rows differ in the number of boxes. In the case where the number of boxes in the last row n is large enough, the number of SYT does not change, especially if m = 1, whether it is closely related to the Catalan number. In addition, we present two main closed formulas for SYTs of angular and “T” shapes.
Weakly weighted sharing and unicity of certain shift polynomials
Authors: Li Xu
Published: July 2021

In this paper, we discuss the unicity problem of certain shift polynomials. Suppose that cj
(j = 1, …, s) be distinct complex numbers, n, m, s and μj
(j = 1, …, s) are integers satisfying n + m > 4σ + 14, where σ = μ
1 + μ
2 + … μs
. We prove that if

p
n

(
γ
)

(
p
(
γ
)
−
1
)

m

∏

j
=
1

s

p

(
γ
+

c
j

)

μ
j

and

q
n

(
γ
)

(
q
(
γ
)
−
1
)

m

∏

j
=
1

s

q

(
γ
+

c
j

)

μ
j

share ″(α(γ),0)″, then either

p
(
γ
)
≡
q
(
γ
)

or

p
n

(
p
−
1
)

m

∏

j
=
1

s

p

(
γ
+

c
j

)

μ
j

−

q
n

(
q
−
1
)

m

∏

j
=
1

s

q

(
γ
+

c
j

)

μ
j

. The results obtained greatly improve the results of Saha (Korean J. Math. 28(4)(2020)) and C. Meng (Mathematica Bohemica 139(2014)).
Gender differences in mathematics academic performance of high school students in western China
Authors: Jiang Peijie
Published: July 2021

The study describes gender differences in mathematics academic performance among high school students in western China. In this study, two research frameworks, knowledge structure and ability structure, were constructed to analyze the scores of western high school mathematics academic proficiency test, and the conclusion was drawn: female students’ mathematics academic performance in high school was significantly better than male students’; in sets, complex numbers, plane vectors, statistics, trigonometric functions, analytic geometry and functional knowledge modules, female students were significantly better than male students. There were no significant differences between male students and female students in common logic, inequalities, algorithms, probability, sequence, solid geometry and derivative knowledge modules. In terms of basic skills, mathematical operations and data analysis, female students were significantly better than male students. There were no significant differences between male students and female students in mathematical abstraction, logical reasoning and intuitive imagination. The design of mathematics curriculum and mathematics test should consider gender factors to ensure fairness.
Dynamic bifurcation for a three-species cooperating model
Authors: Li Junyan , Wu Ruili
Published: July 2021

A dynamic bifurcation analysis on a three-species cooperating model was presented and it was proved that the problem bifurcated an attractor as the parameter λ crossed the critical value λ0. The analysis was based on the attractor bifurcation theory together with the central manifold reduction.
Comparison study in statistical estimation of gene effects based on a real data set
Authors: Sheng Xiaona , Ma Yuqiu , Zhou Jiabin , Zhou Jingjing
Published: July 2021

Gene mapping study is very important task in current biostatistics and real life science. Most biological traits are mainly controlled by the genetic factors, i.e., the function of genes in the genome, and also affected by some environment factors. Reasonable statistical theory and methods should be used in the gene mapping study, so that the gene effects can be inferred precisely and reliable evidence can be further provided to practical domains of genetics and medicine. In this paper, we compare two statistical methods (conventional LSE method and the Dantzig Selector method) on estimating gene effects in the framework of linear model, and make some comparison on them. The two methods are illustrated by applying to a real data set. The analyzing results show that the Dantzig Selector method has some advantagement although the two methods give similar parameter estimates.
Assessing the role of voluntary nucleic acid testing with mandatory isolation in the control of COVID-19 using a household epidemic model
Authors: Liang Yan
Published: July 2021

The COVID-19 epidemic has had a major impact on people’s lives around the world, and many countries and regions have adopted voluntary nucleic acid testing with mandatory isolation for confirmed household to control COVID-19. Based on the method of branching process, this paper analyzes the influence of related factors on the control effect of voluntary nucleic acid testing with mandatory isolation for confirmed household by establishing a specific household model. Through numerical simulation and comparative analysis, we found that increasing the proportion of voluntary nucleic acid testing and shortening the start time of voluntary testing could enhance the epidemic control effect of this measure. At the same time, the proportion of the symptomatic will also have an impact on the effectiveness of the measure.
Analysis of climate change characteristics of wind in Baoshan —Based on annual data from 2011 to 2020
Authors: Zheng Zhibo , Gao Jingjing , Deng Jianyi , Sun Jiangjie
Published: July 2021

Based on the meteorological data of Baoshan from 2011 to 2020, this paper used SPSS software to fit the climate change characteristics of dominant wind direction and wind force in Baoshan City in recent 10 years. The results show that the wind direction and wind data of Baoshan from 2011 to 2020 are processed. The main wind force is light wind, accounting for 72.7%. The wind force of 5-6 occurred during February 11-13, 2012 and March 10, 2012. The main wind direction was non-continuous wind direction, accounting for 69.2%. The ARIMA(3,0,1) model in time series analysis theory was used to fit the wind data, and the validity was good.
Image encryption based on Kronecker inner product over finite fields and adversarial neural network
Authors: Zou Shengliang , Xia Weixia , Zhu Gailin , Liang Yaru , Wu Jianhua
Published: July 2021

An image encryption algorithm based on Kronecker inner product matrix over the finite field and adversarial neural network (ANN) is designed. The Kronecker inner product matrix transform and the ANN fulfil the tasks of confusion and diffusion simultaneously. In addition, the look-up table method is used to complete the addition and multiplication operations over GF(2
B
) finite fields, which can effectively improve the finite field computation speed while retaining its performance of non rounding errors. At the same time, relying on the secure hash function SHA-256 of the plain image to control the Logistic-Sine map greatly improves the diffusion and security of the encryption system. The simulation results verify that the proposed algorithm not only has high security and sufficient sensitivity, but also has a good resistance to various common attacks.
Pre-training and multi-task training for federated keyword extraction
Authors: Guo Lingqi , Sun Haifeng , Shi Zhizhong , Lei Tao
Published: July 2021

The generalization ability of supervised model is relatively weak in keyword extraction technology. In order to effectively improve the robustness and accuracy of the model, the key to overcome this problem is collect more data for training process. However, the text as an privacy information, it is harder and harder to collect. To solve this problem, we apply federal learning to use user privacy data locally to improve the keyword extraction performance. In order to integrate the unlabeled user utterances to the semantic parsing model, we proposed a Pre-training and multi-task based federated keyword extraction model. The user models learn local information via unsupervised setting and the core model learns the supervised setting.
Network estimation of multi-dimensional binary variables with application to divorce data
Authors: Yang Yihe , Luo Renwen , Guo Bing , Luo Yingting , Pan Jianxin
Published: July 2021

The cross-integration of statistics with social and scientific applications is one of the most popular topics in the past decade. Motivated by divorce data collected from the rural areas of Sichuan Province, China, we propose a new method to estimate the network of multiple binary variables, which specifies the dependence structures of multiple binary variables through the Gaussian copula model. Method of moments is employed to estimate the latent correlation matrix of the multiple binary variables. Alternating direction method of multipliers algorithm is then used to estimate the corresponding latent Gaussian network from the empirical latent correlation matrix. This method modifies the traditional estimation of latent Gaussian network from the perspectives of computational efficiency and positive definite guarantee. Analysis of the divorce data is conducted for illustration.
Improvement of the population competition model
Authors: Chen Bowen
Published: July 2021

Classic population competition model with fixed parameters can only be used under the condition of constant living environment, which is impossible in real life. So it has little practical significance in some cases. In this paper, the model will be improved so that it can be used in a changeable living environment. The objective is to establish the relationship between model parameters and independent variables of external conditions with multivariate regression. Growth curves of populations competing with each other are obtained by piecewise prediction. The data used in the regression are obtained by doing experiments. This paper will take wood rot fungus as an example to explain how to establish the relationship by doing experiments, and apply the new model and the classic one with artificial simulation data, so that two groups of predicted population competition curves are obtained. It has been found that the new model can more accurately describe population competition in the case of severe fluctuations in external environment, while the classic model has obvious errors. Finally, this paper briefly describes other advantages of the new model.
Forecasting Thailand inbound tourist flow association for tourism demand
Authors: Jiang Danhua , Liu Jianxu , Sirisrisakulchai Jirakom , Sriboonchitta Songsak
Published: July 2021

The purpose of this paper is to study the tourism demand of Thailand from six major source countries (CN, JP, KO, MAS, SG and LA) in two regions of Asia (East Asia and Southeast Asia). The data is from 1997q1 to 2020q1, which can also provide some advice for the recovery of Thailand tourism post COVID-19. Compared with previous studies, we consider the dependence of tourist flow in the same region. Precisely, we estimated the impact of tourism flows between pairwise countries in each region. This also provides a complement to the subsequent research on the structure of tourism dependence for tourism demand of Thailand. The Copula-based approaches are increasingly being used for tourism demand, we apply the copula-ARDL (ECM) framework to forecast tourist arrivals from two regions. Using the characteristics of correlation matrix in the trivariate Gaussian copula model, we have innovatively performed unconstrained parametric optimization of these two models to ensure the accuracy of the forecasting.
A comparative analysis on the import and export trade patterns of China’s mechanical and electrical products
Authors: Hong Yu , Qu Bingbing , Wang Yuan , Liu Ting
Published: July 2021

This study uses annual data from 1985 to 2019 to analyze the export and import trade patterns of mechanical and electrical products of China. We employ H-index, or the difference between net export capability and symmetric revealed comparative advantage, to assess the trade policies in exports and imports. The results reveal that China has comparative advantage in the imports, and has had comparative disadvantage in the exports before 1999. In recent years, the policy of trade protectionism has been adopted, which promotes exports in terms of exports and restricts imports in terms of imports.
The linkage between tourism development and quality of life: A Copula-based Seemingly Unrelated Regression (SUR) model
Authors: Xue Yuting , Liu Jianxu , Piboonrungroj Pairach , Buranasiri Benjenop , Sriboonchitta Songsak
Published: July 2021

This paper investigates relationships between international tourist arrivals to China and local residents’ quality of life (QOL). We employed Seemingly Unrelated Regression (SUR) model based on the Gaussian Copula approach. Data on international tourist arrivals from Japan, South Korea, and Russia to China during 1994 and 2018 were employed in the model. Findings show direct impacts of inbound tourism on resident’s QOL. Moreover, result reveals an intrinsically reciprocal linkage between national economic growth and residents’ QOL across origins of tourists. Novel contributions of this paper include the robust and objective approach to estimate relationship between international tourism and QOL of local residents.
Comparison of photon-pair generation rate between the sideband and fundamental modes of spontaneous four-wave mixing
Authors: Lee Dongjin , Park Kyungdeuk , Shin Heedeuk
Published: July 2021

Spontaneous four-wave mixing (SpFWM) in fiber optics has been investigated due to its high photon-pair generation rate and negligible connection loss to fiber optic systems. Photon pairs generated in the fundamental or sideband modes satisfy SpFWM’s phase matching condition, and the pair-generation efficiency of both modes has been considered nearly identical. Here, we directly compare the pair-generation efficiency of the fundamental and sideband modes. Dispersion in optical fiber varies unevenly, and SpFWM in the sideband mode is more sensitive to the medium’s dispersion properties than in the fundamental mode, inducing lower pair-generation efficiency. These strong non-uniformity effects in the sideband mode will affect the photon-pair generation and four-wave mixing based quantum and nonlinear applications.
Tribocorrosion investigation of 316L stainless steel: the synergistic effect between chloride ion and sulfate ion
Authors: Tan Liwen , Wang Zhongwei , Ma Yanlong , Yan Yu , Qiao Lijie
Published: July 2021

Tribocorrosion is a failure phenomenon which involves synergistic effect of electrochemical corrosion and mechanical wear. It usually results into early failure of mechanical components than simple wear and corrosion. Chloride (Cl−) and sulfate ions

SO

4

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are often found together in corrosive media. In this study, the synergistic effect of Cl− and

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on tribocorrosion of 316L stainless steel was studied by changing the ratio of

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/Cl− in corrosive solution from 0.31 M : 0 to 0 : 0.62 M. The stainless steel was worn against with a ZrO2 sphere. The coefficient of friction (COF), material loss volume, surface micro-topographies and surface chemical composition in different solutions were compared to explore the synergism between

SO

4

2
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and Cl−. The results indicated that the mix of Cl− and

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reduced material loss volume by a quarter when compared with that in pure Na2SO4 or NaCl solution. More than half of material loss was caused by the synergism between wear and corrosion in mixing solutions. The synergistic effect between

SO

4

2
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and Cl− could promote the transmission of metal into oxides. This had two effects on tribocorrosion. First, the existence of oxides would cause abrasion which accelerated wear-affected corrosion and enhanced mechanical wear (corrosion-affected wear). On the other side, the transmission of metal into oxides benefited for the formation of tribo-film. The flexible stainless steel needed to coordinate deformation with the tribo-film which had relatively low deformability. This aggravated deformation of stainless steel and promoted surface work-hardening effect. It was helpful for stainless steel to resist wear, thus, the corrosion-affected wear was decreased.
Temporal characterization of two-octave infrared pulses by frequency resolved optical switching
Authors: Leblanc Adrien , Longa Adrien , Kumar Mayank , Laramée Antoine , Dansereau Charles , Ibrahim Heide , Lassonde Philippe , Légaré François
Published: July 2021

We present the temporal characterization of infrared pulses with spectra extending from 0.55 to 2.5 μm by using the frequency resolved optical switching (FROSt) technique. The pulses are obtained by broadening femtosecond pulses at 1.75 μm central wavelength in a two-stage hollow core fiber setup. This work demonstrates the capability of the FROSt technique to temporally characterize pulses with ultra-broadband spectra. Being free of phase-matching constraints, it enables the characterization of pulses with very low energy at the limit of the detection threshold and with arbitrary long pulse duration. This strength of the FROSt technique is illustrated by the characterization of supercontinua pulses whose spectra span over two octaves and with only 150 nJ energy that is spread temporally over almost 40 ps. The FROSt capabilities provide a versatile tool for the characterization of sub-cycle pulses and to study nonlinear processes such as supercontinuum generation.
2021 roadmap for sodium-ion batteries
Authors: Tapia-Ruiz Nuria , Armstrong A Robert , Alptekin Hande , Amores Marco A , Au Heather , Barker Jerry , Boston Rebecca , Brant William R , Brittain Jake M , Chen Yue , Chhowalla Manish , Choi Yong-Seok , Costa Sara I R , Crespo Ribadeneyra Maria , Cussen Serena A , Cussen Edmund J , David William I F , Desai Aamod V , Dickson Stewart A M , Eweka Emmanuel I , Forero-Saboya Juan D , Grey Clare P , Griffin John M , Gross Peter , Hua Xiao , Irvine John T S , Johansson Patrik , Jones Martin O , Karlsmo Martin , Kendrick Emma , Kim Eunjeong , Kolosov Oleg V , Li Zhuangnan , Mertens Stijn F L , Mogensen Ronnie , Monconduit Laure , Morris Russell E , Naylor Andrew J , Nikman Shahin , O’Keefe Christopher A , Ould Darren M C , Palgrave R G , Poizot Philippe , Ponrouch Alexandre , Renault Stéven , Reynolds Emily M , Rudola Ashish , Sayers Ruth , Scanlon David O , Sen S , Seymour Valerie R , Silván Begoña , Sougrati Moulay Tahar , Stievano Lorenzo , Stone Grant S , Thomas Chris I , Titirici Maria-Magdalena , Tong Jincheng , Wood Thomas J , Wright Dominic S , Younesi Reza
Published: July 2021

Increasing concerns regarding the sustainability of lithium sources, due to their limited availability and consequent expected price increase, have raised awareness of the importance of developing alternative energy-storage candidates that can sustain the ever-growing energy demand. Furthermore, limitations on the availability of the transition metals used in the manufacturing of cathode materials, together with questionable mining practices, are driving development towards more sustainable elements. Given the uniformly high abundance and cost-effectiveness of sodium, as well as its very suitable redox potential (close to that of lithium), sodium-ion battery technology offers tremendous potential to be a counterpart to lithium-ion batteries (LIBs) in different application scenarios, such as stationary energy storage and low-cost vehicles. This potential is reflected by the major investments that are being made by industry in a wide variety of markets and in diverse material combinations. Despite the associated advantages of being a drop-in replacement for LIBs, there are remarkable differences in the physicochemical properties between sodium and lithium that give rise to different behaviours, for example, different coordination preferences in compounds, desolvation energies, or solubility of the solid–electrolyte interphase inorganic salt components. This demands a more detailed study of the underlying physical and chemical processes occurring in sodium-ion batteries and allows great scope for groundbreaking advances in the field, from lab-scale to scale-up. This roadmap provides an extensive review by experts in academia and industry of the current state of the art in 2021 and the different research directions and strategies currently underway to improve the performance of sodium-ion batteries. The aim is to provide an opinion with respect to the current challenges and opportunities, from the fundamental properties to the practical applications of this technology.
A genomic data resource for predicting antimicrobial resistance from laboratory-derived antimicrobial susceptibility phenotypes
Authors: VanOeffelen Margo , Nguyen Marcus , Aytan-Aktug Derya , Brettin Thomas , Dietrich Emily M , Kenyon Ronald W , Machi Dustin , Mao Chunhong , Olson Robert , Pusch Gordon D , Shukla Maulik , Stevens Rick , Vonstein Veronika , Warren Andrew S , Wattam Alice R , Yoo Hyunseung , Davis James J
Published: July 2021

Antimicrobial resistance (AMR) is a major global health threat that affects millions of people each year. Funding agencies worldwide and the global research community have expended considerable capital and effort tracking the evolution and spread of AMR by isolating and sequencing bacterial strains and performing antimicrobial susceptibility testing (AST). For the last several years, we have been capturing these efforts by curating data from the literature and data resources and building a set of assembled bacterial genome sequences that are paired with laboratory-derived AST data. This collection currently contains AST data for over 67 000 genomes encompassing approximately 40 genera and over 100 species. In this paper, we describe the characteristics of this collection, highlighting areas where sampling is comparatively deep or shallow, and showing areas where attention is needed from the research community to improve sampling and tracking efforts. In addition to using the data to track the evolution and spread of AMR, it also serves as a useful starting point for building machine learning models for predicting AMR phenotypes. We demonstrate this by describing two machine learning models that are built from the entire dataset to show where the predictive power is comparatively high or low. This AMR metadata collection is freely available and maintained on the Bacterial and Viral Bioinformatics Center (BV-BRC) FTP site ftp://ftp.bvbrc.org/RELEASE_NOTES/PATRIC_genomes_AMR.txt.
RefRGim: an intelligent reference panel reconstruction method for genotype imputation with convolutional neural networks
Authors: Shi Shuo , Qian Qiheng , Yu Shuhuan , Wang Qi , Wang Jinyue , Zeng Jingyao , Du Zhenglin , Xiao Jingfa
Published: July 2021

Genotype imputation is a statistical method for estimating missing genotypes from a denser haplotype reference panel. Existing methods usually performed well on common variants, but they may not be ideal for low-frequency and rare variants. Previous studies showed that the population similarity between study and reference panels is one of the key factors influencing the imputation accuracy. Here, we developed an imputation reference panel reconstruction method (RefRGim) using convolutional neural networks (CNNs), which can generate a study-specified reference panel for each input data based on the genetic similarity of individuals from current study and references. The CNNs were pretrained with single nucleotide polymorphism data from the 1000 Genomes Project. Our evaluations showed that genotype imputation with RefRGim can achieve higher accuracies than original reference panel, especially for low-frequency and rare variants. RefRGim will serve as an efficient reference panel reconstruction method for genotype imputation. RefRGim is freely available via GitHub: https://github.com/shishuo16/RefRGim