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Influence of dissipation on solitary wave solution to generalized Boussinesq equation

Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 477-498页

作者： Weiguo ZHANG Siyu HONG Xingqian LING Wenxia LI College of Science University of Shanghai for Science and TechnologyShanghai 200093China

This paper uses the theory of planar dynamic systems and the knowledge of reaction-diffusion equations,and then studies the bounded traveling wave solution of the generalized Boussinesq equation affected by dissipation and the influence of dissipation on solitary waves.The dynamic system corresponding to the traveling wave solution of the equation is qualitatively analyzed in detail.The influence of the dissipation coefficient on the solution behavior of the bounded traveling wave is studied,and the critical values that can describe the magnitude of the dissipation effect are,respectively,found for the two cases of b_30 in the equation.The results show that,when the dissipation effect is significant(i.e.,r is greater than the critical value in a certain situation),the traveling wave solution to the generalized Boussinesq equation appears as a kink-shaped solitary wave solution;when the dissipation effect is small(i.e.,r is smaller than the critical value in a certain situation),the traveling wave solution to the equation appears as the oscillation attenuation solution.By using the hypothesis undetermined method,all possible solitary wave solutions to the equation when there is no dissipation effect(i.e.,r=0)and the partial kink-shaped solitary wave solution when the dissipation effect is significant are obtained;in particular,when the dissipation effect is small,an approximate solution of the oscillation attenuation solution can be achieved.This paper is further based on the idea of the homogenization principles.By establishing an integral equation reflecting the relationship between the approximate solution of the oscillation attenuation solution and the exact solution obtained in the paper,and by investigating the asymptotic behavior of the solution at infinity,the error estimate between the approximate solution of the oscillation attenuation solution and the exact solution is obtained,which is an infinitesimal amount that decays exponentially.The influence of the dissipation coefficient on the ampli

关键词： generalized Boussinesq equation influence of dissipation qualitative analysis solitary wave solution oscillation attenuation solution error estimation

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Uncertainty index and stock volatility prediction:evidence from international markets

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Financial Innovation 2022年第1期8卷 1738-1781页

作者： Xue Gong Weiguo ZHANG Weijun Xu Zhe Li School of Business Administration South China University of TechnologyGuangzhouChina Financial ServiceInnovation and Risk Management Research Base of Guangzhou GuangzhouChina Business School Nanjing Normal UniversityNanjingChina.

This study investigates the predictability of a fixed uncertainty index(UI)for realized variances(volatility)in the international stock markets from a high-frequency perspective.We construct a composite UI based on the scaled principal component analysis(s-PCA)method and demonstrate that it exhibits significant in-and out-of-sample predictabilities for realized variances in global stock markets.This predictive power is more powerful than those of two commonly employed competing methods,namely,PCA and the partial least squares(PLS)methods.The result is robust in several checks.Further,we explain that s-PCA outperforms other dimension-reduction methods since it can effectively increase the impacts of strong predictors and decrease those of weak factors.The implications of this research are significant for investors who allocate assets globally.

关键词： Uncertainty index High-frequency data Realized variance Scaled-PCA

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Can information confusion caused by the financing model of new economy companies be eliminated?

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China Journal of Accounting Research 2021年第1期14卷 1-23页

作者： Xuejing Xie Weiguo ZHANG Accounting department Tsinghua UniversityChina School of Accountancy Shanghai University of Finance and EconomicsChina

New economy companies often use convertible and redeemable preferred shares with equity and debt characteristics as financing tools to reduce risk during their early stages of growth.According to relevant accounting standards,such preferred shares should be classified as financial liabilities and measured at fair value,with changes in fair value recognized in profit or loss.This can lead to confusing financial information:the better a company’s development prospects,the higher its redemption or conversion price and loss,which can result in a large negative net asset value.A successful initial public offering,however,could offset large losses and negative net asset value.Following the development of accounting standards,this article thoroughly analyzes various proposals to modify relevant accounting standards and eliminate confusing information.This article also proposes possible problems and solutions as a reference for accounting standard setters and the various stakeholders in new economy companies.

关键词： New economy companies Convertible and redeemable preferred shares Hybrid instruments Accounting standards

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Design on the Prestressed Concrete Frame Beam-column

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1397-1403页

作者： zhang Taiyue zhang weiguo WANG Sihai GUO Yiqing Architectural Engineering Institute Jiangsu College of Engineering and TechnologyNantong 226000China Nantong Sijian Group Co. LtdNantong 226000China School of Materials Science and Engineering Tongji UniversityShanghai 201804China

A bidirectional ribbed concrete beam slab structure was widly adopted for the upper space of industrial buildings.To maintain ample space and minimize the presence of conventional columns,a bidirectional prestressed concrete beam is often employed.The intersection node of the prestressed concrete frame beam column was characterized by a high density of steel reinforcement,significant structural loads,and complex construction requirements.To ensure the quality,safety,and progress of prestressed frame beamcolumn intersection nodes during construction,this article proposed a new technology for constructing such nodes,which includes setting the tensioning and haunching ends of nodes at different positions,using ABAQUS finite element software to optimize the design of cross-sectional dimensions,conducting stress analysis simulations.

关键词： prestressed concrete beam-column intersection node finite element analysis optimal design digital simulation

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PALES: Optimizing Secure Data Deletion in SSDs via Page Group and Reprogram Speedup

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Chinese Journal of Electronics 2022年第1期31卷 40-51页

作者： NIE Shiqiang WU weiguo zhang Chi zhang Chen Department of Computer Science and Technology Xi’an Jiaotong University

As solid-state drives(SSD) have been widely adopted, secure data deletion becomes an essential component for ensuring user privacy, preventing sensitive data leakage. Due to the erase-before-write property,erasure operation and scrub operation substituting for overwriting technologies are proposed to meet the requirements. However, both methods bring the severe page-copying issue, declining read/write performance, and shortening the lifetime of SSD. In this paper, this issue is alleviated by reserving pages at the page allocation stage to mitigate program disturbance and increasing program step voltage during reprogramming operation to reduce the reprogram latency. The proposed scheme is evaluated by a series of experiments; the results show that the proposed scheme could achieve significant deletion time reduction and alleviate page-copying overhead.

关键词： NAND flash Data deletion Reprogram Program voltage

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Dynamic spatiotemporal correlation coefficient based on adaptive weight

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Financial Innovation 2023年第1期9卷 424-466页

作者： Guoli Mo Chunzhi Tan Weiguo ZHANG Xuezeng Yu School of Economics Guangxi UniversityNanningGuangxi 530004China School of Business Administration South China University of TechnologyGuangzhouGuangdong 510641China

Risk management is an important aspect of financial research because correlations among financial data are essential in evaluating portfolio risk.Among various correlations,spatiotemporal correlations involve economic entity attributes and are interrelated in space and time.Such correlations have therefore drawn increasing attention in financial risk management.However,classical correlation measurements are typically based on either time series correlations or spatial dependence;they cannot be directly applied to financial data with spatiotemporal correlations.The spatiotemporal correlation coefficient model with adaptive weight proposed in this paper can(1)address the absolute quantity,dynamic quantity,and dynamic development of financial data and(2)be used for risk grading,financial risk evaluation,and portfolio management.To verify the validity and superiority of this model,cluster analysis results and portfolio performance are compared with a classical model with time series correlation or spatial correlation,respectively.Empirical findings show that the proposed coefficient is highly effective and convenient compared to others.Overall,our method provides a highly efficient financial risk management method with valuable implications for investors and financial institutions.

关键词： Spatiotemporal correlation Absolute distance Growth distance Fluctuation distance Adaptive weight

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TEGDME Electrolyte Additive for High-performance Zinc Anodes

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Chemical Research in Chinese Universities 2023年第6期39卷 1037-1043页

作者： zhang weiguo zhang Chong WANG Hongzhi WANG huanhuan Department of Applied Chemistry School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350P.R.China

Aqueous zinc ion batteries(AZIBs)are expected to have a wide range of applications for large-scale electrochemical energy storage systems,but their practical application is severely limited by the presence of zinc dendrites,hydrogen evolution reactions(HER),corrosion reactions,and other problems.Electrolyte optimization is considered to be one of the most effective methods for improving zinc anodes due to its simplicity,low production cost and remarkable effectiveness in suppressing zinc dendrite growth.In this paper,a tetra(ethylene glycol)dimethyl ether(TEGDME)electrolyte additive was used to improve the stability of the zinc anode by adding 0.1 g/L TEGDME to the conventional ZnSO_(4) electrolyte to prepare a mixed electrolyte.The effect of TEGDME on the side reactions of zinc anode was first assessed by linear sweep voltammetry(LSV)and potentiodynamic polarization.The effect of TEGDME on the structure and morphology of zinc surfaces was observed using an X-ray diffractometer(XRD)and a scanning electron microscope(SEM).And finally,the electrochemical performance of Zn|Zn symmetric cells,Zn||Ti asymmetric cells and Zn-MnO_(2) full cells with ZnSO_(4)+TEGDME electrolyte was tested by cyclic voltammetry(CV)and galvanostatic cycling.The results show that the addition of TEGDME improves the surface wettability of the Zn anode and reduces the growth of dendrites through solvation structure modulation to suppress HER and zinc corrosion.Thus,TEGDME keeps the Zn anode to maintain a flat surface during charging and discharging,improving the reversibility of plating/stripping.The cycle life of the Zn||Ti asymmetric cell was improved and the Coulombic efficiency was 100%after 100 cycles.The Zn||Zn symmetric cells can be cycled stably for 1800 h at a current density of 1 mA/cm^(2) and a fixed capacity of 1 mA·h/cm^(2),while the capacity retention of the Zn-MnO_(2) full cell can be effectively improved from 51.46%to 68.29%at 100 cycles.By using TEGDME electrolyte additives,the cycle life of aqueous zinc ion batteries can be

关键词： Aqueous zinc ion battery Zinc dendrite Hydrogen evolution reaction Solvation structure Cycle life

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Constructions of vectorial Boolean functions with good cryptographic properties

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Science China(Information Sciences) 2016年第11期59卷 233-234页

作者： Luyang LI Weiguo ZHANG State Key Laboratory of Integrated Services Networks Xidian University Science and Technology on Communication Security Laboratory

Dear editor,Vectorial Boolean functions play an important role in designing certain stream cipher schemes,such as filtering generators and nonlinear combiners.To be used in the aforementioned schemes,vectorial Boolean functions must satisfy several criteria.The best affine and linear approximation attacks show that high nonlinearity is significant for designing cryptographically strong functions.Correlation-immune functions were first introduced by Siegenthaler[1]in order to construct

关键词： In Constructions of vectorial Boolean functions with good cryptographic properties

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Co-ordinated combination of Embden-Meyerhof-Parnas pathway and pentose phosphate pathway in Escherichia coli to promote L-tryptophan production

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BIOCELL 2022年第10期46卷 2303-2313页

作者： SHUAI LIU JIANZHONG XU TINGSHAN LIU ZHIMING RAO Weiguo ZHANG The Key Laboratory of Industrial Biotechnology Ministry of EducationMinistry of EducationSchool of BiotechnologyJiangnan UniversityWuxi214122China National Engineering Laboratory for Cereal Fermentation Technology(NELCF) Jiangnan UniversityWuxi214122China

In this study,phosphoenolpyruvate and erythrose-4-phosphate are efficiently supplied by collaborative design of Embden-Meyerhof-Parnas(EMP)pathway and pentose phosphate(PP)pathway in Escherichia coli,thus increasing the L-tryptophan production.Firstly,the effects of disrupting EMP pathway on L-tryptophan production were studied,and the results indicated that the strain with deletion of phosphofructokinase A(i.e.,E.coli JW-5ΔpfkA)produced 23.4±2.1 g/L of L-tryptophan production.However,deletion of phosphofructokinase A and glucosephosphate isomerase is not conducive to glucose consumption and cell growth,especially deletion of glucosephosphate isomerase.Next,the carbon flux in PP pathway was enhanced by introduction of the desensitized glucose-6-phosphate dehydrogenase(zwf)and 6-phosphogluconate dehydrogenase(gnd)and thus increasing the L-tryptophan production(i.e.,26.5±3.2 g/L vs.21.7±1.3 g/L)without obviously changing the cell growth(i.e.,0.41 h^(-1) vs.0.44 h^(-1))as compared with the original strain JW-5.Finally,the effects of co-modifying EMP pathway and PP pathway on L-tryptophan production were investigated.It was found that the strain with deletion of phosphofructokinase A as well as introduction of the desensitized zwf and gnd(i.e.,E.coli JW-5 zwf243 gnd361ΔpfkA)produced 31.9±2.7 g/L of L-tryptophan,which was 47.0%higher than that of strain JW-5.In addition,the glucose consumption rate of strain JW-5 zwf243 gnd361ΔpfkA was obviously increased despite of the bad cell growth as compared with strain JW-5.The results of this study have important reference value for the following application of metabolic engineering to improve aromatic amino acids producing strains.

关键词： Escherichia coli L-tryptophan production Phosphoenolpyruvate Erythrose-4-phosphate Collaborative design

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Construction of balanced Boolean functions with high nonlinearity, good local and global avalanche characteristics

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Frontiers of Mathematics in China 2016年第2期11卷 339-352页

作者： Luyang LI Yujuan SUN Weiguo ZHANG ISN Laboratory Xidian University Xi'an 710071 China Science and Technology on Communication Security Laboratory Chengdu 610041 China

拥有多重密码的标准的布尔功能在对称的 cryptosystems 的设计起一个重要作用。为密码的布尔功能的下列标准经常被考虑：高非线性， balancedness，严格的雪崩标准，和全球雪崩特征。在这些标准之中的交易是一个困难的问题并且吸引了许... 详细信息

拥有多重密码的标准的布尔功能在对称的 cryptosystems 的设计起一个重要作用。为密码的布尔功能的下列标准经常被考虑：高非线性， balancedness，严格的雪崩标准，和全球雪崩特征。在这些标准之中的交易是一个困难的问题并且吸引了许多研究人员。在这份报纸，二个构造方法被提供与高非线性获得平衡布尔功能。而且，构造功能满足严格的雪崩标准并且有好全球雪崩特征性质。构造功能的代数学的免疫也被考虑。

关键词：严格雪崩准则函数构造非线性平衡性特性加密标准布尔函数密码系统

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