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Asymptotic Stability of Monotone Decreasing Kink Profile Solitary Wave Solutions for Generalized KdV-Burgers Equation

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 475-490页

作者： Wei-guo ZHANG Wen-xia li Sheng-er DENG Xiang li College of Science University of Shanghai for Science and Technology

In this paper,we focus on studying the asymptotic stability of the monotone decreasing kink profile solitary wave solutions for the generalized KdV-Burgers *** obtain the estimate of the firstorder and second-order derivatives for monotone decreasing kink profile solitary wave solutions,and overcome the difficulties caused by high-order nonlinear terms in the generalized KdV-Burgers equation in the estimate by using L2 energy estimating method and Young *** prove that the monotone decreasing kink profile solitary wave solutions are asymptotically stable in ***,we obtain the decay rate of the perturbationψin the sense of L^2 and L^∞norm,respectively,which are(1+t)^-1/2 and(1+t)^-1/4 by using Gargliado-Nirenberg inequality.

关键词： Generalized KdV-Burgers equation a priori estimate asymptotic stability decay rate

Generalized Ejiri’s Rigidity Theorem for Submanifolds in Pinched Manifolds(In memory of Professor Chaohao gu on his 90th birthday)

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Chinese Annals of Mathematics,Series B 2020年第2期41卷 285-302页

作者： Hongwei XU li LEI Juanru gu Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China

Let Mn(n ≥ 4) be an oriented compact submanifold with parallel mean curvature in an(n + p)-dimensional complete simply connected Riemannian manifold Nn+*** there exists a constant δ(n, p) ∈(0, 1) such that if the sectional curvature of N satisfies■ , and if M has a lower bound for Ricci curvature and an upper bound for scalar curvature, then N is isometric to Sn+p. Moreover, M is either a totally umbilic sphere■ , a Clifford hypersurface Sm■ in the totally umbilic sphere ■, or■ . This is a generalization of Ejiri’s rigidity theorem.

关键词： Minimal submanifold Ejiri rigidity theorem Ricci curvature Mean curvature

Sentiment analysis using deep learning approaches:an overview

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Science China(Information Sciences) 2020年第1期63卷 21-56页

作者： Olivier HABIMANA Yuhua li Ruixuan li Xiwu gu Ge YU School of Computer Science and Technology Huazhong University of Science and Technology School of Computer Science and Engineering Northeastern University

Nowadays, with the increasing number of Web 2.0 tools, users generate huge amounts of data in an enormous and dynamic way. In this regard, the sentiment analysis appeared to be an important tool that allows the automation of getting insight from the user-generated data. Recently, deep learning approaches have been proposed for different sentiment analysis tasks and have achieved state-of-the-art results. Therefore, in order to help researchers to depict quickly the current progress as well as current issues to be addressed, in this paper, we review deep learning approaches that have been applied to various sentiment analysis tasks and their trends of development. This study also provides the performance analysis of different deep learning models on a particular dataset at the end of each sentiment analysis task. Toward the end, the review highlights current issues and hypothesized solutions to be taken into account in future work. Moreover, based on knowledge learned from previous studies, the future work subsection shows the suggestions that can be incorporated into new deep learning models to yield better performance. Suggestions include the use of bidirectional encoder representations from transformers(BerT), sentiment-specific word embedding models, cognition-based attention models, common sense knowledge, reinforcement learning, and generative adversarial networks.

关键词： sentiment analysis opinion mining deep learning neural network natural language processing(NLP) social network

Prediction of(n,2n)reaction cross-sections of long-lived fission products based on tensor model

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Nuclear Science and Techniques 2024年第10期35卷 208-221页

作者： Jia-li Huang Hui Wang Ying-Ge Huang er-Xi Xiao Yu-Jie Feng Xin Lei Fu-Chang gu Long Zhu Yong-Jing Chen Jun Su Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China

Interest has recently emerged in potential applications of(n,2n)reactions of unstable *** have arisen because of the scarcity of experimental cross-sectional *** study aims to predict the(n,2n)reaction cross-section of long-lived fission products based on a tensor *** tensor model is an extension of the collaborative filtering algorithm used for nuclear *** is based on tensor decomposition and completion to predict(n,2n)reaction cross-sections;the corresponding EXFOR data are applied as training *** reliability of the proposed tensor model was validated by comparing the calculations with data from EXFOR and different *** were made for long-lived fission products such as^(60)Co,^(79)Se,^(93)Zr,^(107)P,^(126)Sn,and^(137)Cs,which provide a predicted energy range to effectively transmute long-lived fission products into shorter-lived or less radioactive *** method could be a powerful tool for completing(n,2n)reaction cross-sectional data and shows the possibility of selective transmutation of nuclear waste.

关键词： (n,2n)Reaction cross-section Tensor model Machine learning Collaborative filtering algorithm Selective transmutation

A Self-Organizing RBF Neural Network Based on Distance Concentration Immune Algorithm

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 276-291页

作者： Junfei Qiao Fei li Cuili Yang Wenjing li Ke gu Beijing University of Technology Beijing 100083China

Radial basis function neural network(RBFNN) is an effective algorithm in nonlinear system identification. How to properly adjust the structure and parameters of RBFNN is quite challenging. To solve this problem, a distance concentration immune algorithm(DCIA) is proposed to self-organize the structure and parameters of the RBFNN in this paper. First, the distance concentration algorithm, which increases the diversity of antibodies, is used to find the global optimal solution. Secondly,the information processing strength(IPS) algorithm is used to avoid the instability that is caused by the hidden layer with neurons split or deleted randomly. However, to improve the forecasting accuracy and reduce the computation time, a sample with the most frequent occurrence of maximum error is proposed to regulate the parameters of the new neuron. In addition, the convergence proof of a self-organizing RBF neural network based on distance concentration immune algorithm(DCIA-SORBFNN) is applied to guarantee the feasibility of algorithm. Finally, several nonlinear functions are used to validate the effectiveness of the algorithm. Experimental results show that the proposed DCIASORBFNN has achieved better nonlinear approximation ability than that of the art relevant competitors.

关键词： Distance concentration immune algorithm(DCIA) information processing strength(IPS) radial basis function neural network(RBFNN)

A speckle noise suppression method based on surface waves investigation and monitoring data

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Acta Oceanologica Sinica 2023年第1期42卷 131-141页

作者： Jingwei gu Xiuzhong li Yijun He School of Marine Sciences Nanjing University of Information Science&TechnologyNanjing210044China

The internal energy distribution of waves can be described using ocean-wave *** many ways,obtaining wave spectra on a global scale is *** waves investigation and monitoring onboard the Chinese-French oceanography satellite is the first space-borne instrument for detecting wave spectra specially,which was launched on October 29,*** can avoid the shortage of synthetic aperture radar detection results while still having some problems,especially with the effects of speckle *** this study,a method to suppress the speckle noise is ***,the empirical formula for background speckle noise is ***,many spatio-temporal representative fluctuation spectra are classified and ***,rational transfer function filtering is used to obtain speckle noise close to the along-track ***,a signal-to-noise ratio threshold is used to suppress the abnormal speckle *** method solves the problems existing in previous denoising methods,such as excessive denoising in the along-track direction and the inability of some abnormal noises to be denoised in the two-dimensional directional wave spectra.

关键词： speckle noise surface waves investigation and monitoring WaveWatch III wave spectra

Environmental Conditions Conducive to the Formation of Multiple Tropical Cyclones over the Western North Pacific

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Advances in Atmospheric Sciences 2024年第10期41卷 2027-2042页

作者： Yining gu Ruifen ZHAN Xiaomeng li Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200030China Institute of Desert and Meteorology China Meteorological AdministrationUrumqi 830002China

There is limited understanding regarding the formation of multiple tropical cyclones(MTCs).This study explores the environmental conditions conducive to MTC formation by objectively determining the atmospheric circulation patterns favorable for MTC formation over the western North *** on 199 MTC events occurring from June to October 1980–2020,four distinct circulation patterns are identified:the monsoon trough(MT)pattern,accounting for 40.3%of occurrences,the confluence zone(CON)pattern at 26.2%,the easterly wave(EW)pattern at 17.8%,and the monsoon gyre(MG)pattern at 15.7%.The MT pattern mainly arises from the interaction between the subtropical high and the monsoon trough,with MTCs forming along the monsoon trough and its *** CON pattern is affected by the subtropical high,the South Asian high,and the monsoon trough,with MTCs emerging at the confluence zone where the prevailing southwesterly and southeasterly flows *** EW pattern is dominated by easterly flows,with MTCs developing along the easterly wave *** in the MG pattern arise within a monsoon vortex characterized by strong southwesterly flows.A quantitative analysis further indicates that MTC formation in the MT pattern is primarily governed by mid-level vertical velocity and low-level vorticity,while mid-level humidity and vertical velocity are significantly important in the other *** meridional shear and convergence of zonal winds are essential in converting barotropic energy from the basic flows to disturbance kinetic energy,acting as the primary source for eddy kinetic energy growth.

关键词： multiple tropical cyclones western North Pacific circulation pattern monsoon trough barotropic energy conversion

Negative self-feedback induced enhancement and transition of spiking activity for class-3 excitability

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Chinese Physics B 2022年第7期31卷 203-213页

作者： li li Zhiguo Zhao Huaguang gu guangdong Key Laboratory of Modern Control Technology Institute of Intelligent ManufacturingGuangdong Academy of SciencesGuangzhou 510070China School of Science Henan Institute of TechnologyXinxiang 453003China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

Post-inhibitory rebound(PIR)spike,which has been widely observed in diverse nervous systems with different physiological functions and simulated in theoretical models with class-2 excitability,presents a counterintuitive nonlinear phenomenon in that the inhibitory effect can facilitate neural firing *** this study,a PIR spike induced by inhibitory stimulation from the resting state corresponding to class-3 excitability that is not related to bifurcation is simulated in the Morris–Lecar ***,the inhibitory self-feedback mediated by an autapse with time delay can evoke tonic/repetitive spiking from phasic/transient *** dynamical mechanism for the PIR spike and the tonic/repetitive spiking is acquired with the phase plane analysis and the shape of the quasi-separatrix *** result extends the counterintuitive phenomenon induced by inhibition to class-3 excitability,which presents a potential function of inhibitory autapse and class-3 neuron in many neuronal systems such as the auditory system.

关键词： post-inhibitory rebound spike class 3 excitability inhibitory autapse neuronal firing

Ultrasmall Nanoparticle ROS Scavengers Based on Polyhedral Oligomeric Silsesquioxanes

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Chinese Journal of Polymer Science 2020年第11期38卷 1149-1156,I0004页

作者： Zhan li Haotian li Jianhua Zhang Xianhu liu Zhipeng gu Yiwen li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China School of Materials Science and Engineering Xihua UniversityChengdu 610039China National Engineering Research Center for Advanced Polymer Processing Technology Zhengzhou UniversityZhengzhou 450002China

Although tremendous efforts have been devoted to the structural and functional tailoring of natural polyphenol-functionalized nan oparticles,preparing ultrasmall sized(ligomeric silsesquioxanes(POSS)-based polyphenol nanopartides(T8^-,T10^-,and T12^-GAPOSS)by accurately functionalizing the POSS surface with plant polyphenol gallic acid units via thiol-Michael"click"*** polyphenol nanoparticles exhibited strong free radical scavenging capacity,good biocompatibility and ability to resist cell oxidative damage,which dem on strated great potentials in inhibiting oxidative stress in duced pathologies.

关键词： Polyhedral oligomeric silsesquioxanes(POSS) Polyphenol Ultrasmall nanoparticles Free radical scavenging