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THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING HABITAT

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Acta Mathematica Scientia 2024年第3期44卷 1096-1114页

作者：赵敏袁荣 school of science Tianjin Chengjian UniversityTianjin300384China Laboratory of mathematics and Complex systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing100875China

In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting *** is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving *** particular,they achieved a complete picture in the local diffusion ***,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s *** using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et *** achieve a complete picture in the nonlocal diffusion case.

关键词： predator-prey system persistence nonlocal dispersal shifting environment

Impact of different interaction behavior on epidemic spreading in time-dependent social networks

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Chinese Physics B 2024年第3期33卷 190-195页

作者：黄帅陈杰李梦玉徐元昊胡茂彬 school of Engineering science University of Science and Technology of ChinaHefei 230026China school of mathematics Southeast UniversityNanjing 210096China

We investigate the impact of pairwise and group interactions on the spread of epidemics through an activity-driven model based on time-dependent *** effects of pairwise/group interaction proportion and pairwise/group interaction intensity are explored by extensive simulation and theoretical *** is demonstrated that altering the group interaction proportion can either hinder or enhance the spread of epidemics,depending on the relative social intensity of group and pairwise *** the group interaction proportion decreases,the impact of reducing group social intensity *** ratio of group and pairwise social intensity can affect the effect of group interaction proportion on the scale of infection.A weak heterogeneous activity distribution can raise the epidemic threshold,and reduce the scale of *** results benefit the design of epidemic control strategy.

关键词： epidemic transmission complex network time-dependent networks social interaction

Fuzzing:Progress,Challenges,and Perspectives

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Computers, Materials & Continua 2024年第1期78卷 1-29页

作者： Zhenhua Yu Zhengqi Liu Xuya Cong Xiaobo Li Li Yin Institute of systems Security and Control College of Computer Science and TechnologyXi'an University of Science and TechnologyXi'an710054China school of mathematics and Information science Baoji University of Arts and SciencesBaoji721013China Institute of systems Engineering Macao University of Science and TechnologyTaipaMacaoChina

As one of the most effective techniques for finding software vulnerabilities,fuzzing has become a hot topic in software *** feeds potentially syntactically or semantically malformed test data to a target program to mine vulnerabilities and crash the *** recent years,considerable efforts have been dedicated by researchers and practitioners towards improving fuzzing,so there aremore and more methods and forms,whichmake it difficult to have a comprehensive understanding of the *** paper conducts a thorough survey of fuzzing,focusing on its general process,classification,common application scenarios,and some state-of-the-art techniques that have been introduced to improve its ***,this paper puts forward key research challenges and proposes possible future research directions that may provide new insights for researchers.

关键词： Fuzzing vulnerability software testing software security

Critical observability of partially observed discrete event systems under cyber attacks

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science China(Information sciences) 2024年第2期67卷 333-334页

作者： Liyun TONG Jinling LIANG Yang LIU Department of mathematics School of SciencesHangzhou Dianzi University school of mathematics Southeast University College of mathematics and Computer science Zhejiang Normal University

The discrete event system(DES) is a dynamic system driven by asynchronous/sudden events and has been widely used in many critical infrastructures, such as electric transportation networks and intelligent transportatio...

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Multiscale analysis-based peridynamic simulation of fracture in porous media

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 1-13页

作者： Zihao YANG Shangkun SHEN Xiaofei GUAN Xindang HE Junzhi CUI school of mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China school of Mathematical sciences Tongji UniversityShanghai 200092China school of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China LSEC ICMSECAcademy of Mathematics and Systems ScienceCASBeijing 100190China

The simulation of fracture in large-scale structures made of porous media remains a challenging *** techniques either assume a homogeneous model,disregarding the microstructure characteristics,or adopt a micro-mechanical model,which incurs an intractable computational cost due to its complex stochastic geometry and physical properties,as well as its nonlinear and multiscale *** this study,we propose a multiscale analysis-based dual-variable-horizon peridynamics(PD)model to efficiently simulate macroscopic structural *** influence of microstructures in porous media on macroscopic structural failure is represented by two PD parameters:the equivalent critical stretch and *** equivalent critical stretch is calculated using the microscale PD model,while the equivalent micro-modulus is obtained through the homogenization method and energy density equivalence between classical continuum mechanics and PD *** examples of porous media with various microstructures demonstrate the validity,accuracy,and efficiency of the proposed method.

关键词： porous media multiscale variable-horizon peridynamic equivalent critical stretch equivalent micro-modulus

Cohomology groups of a new class of Kadison-Singer algebras

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science China mathematics 2024年第3期67卷 593-606页

作者： Guangyu An Xing Cheng Jun Sheng school of mathematics and Data science Shaanxi University of Science and TechnologyXi’an 710021China

Let N be a maximal discrete nest on an infinite-dimensional separable Hilbert space H,ξ=∑^(∞)_(n=1)en/2n be a separating vector for the commutant N',E_(ξ)be the projection from H onto the subspace[Cξ]spanned by the vectorξ,and Q be the projection from K=H⊕H⊕H onto the closed subspace{(η,η,η)^(T):η∈H}.Suppose that L is the projection lattice generated by the projections(E_(ξ) 0 0 0 0 0 0 0 0),{(E 0 0 0 0 0 0 0 0):E∈N},(I 0 0 0 I 0 0 0 0) and *** show that L is a Kadison-Singer lattice with the trivial ***,we prove that every n-th bounded cohomology group H~n(AlgL,B(K))with coefficients in B(K)is trivial for n≥1.

关键词： Kadison-Singer algebra Kadison-Singer lattice derivation cohomology group

Balancing Openness and Protection:Homogenization of Regulatory Laws in Digital Service Trade

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China Finance and Economic Review 2024年第2期13卷 67-89页

作者： Cuihong Yang Xiaolin Wang Huijuan Wang Yan Xia Academy of mathematics and systems science Chinese Academy of Sciences(CAS) school of Economics and Management University of Chinese Academy of Sciences(UCAS) Academy of mathematics and systems science CASand School of Economics and ManagementUCAS school of Statistics and mathematics Central University of Finance and Economics. Institutes of science and Development CAS school of Public Policy and Management UCAS

Digital service trade has emerged as a pivotal engine for global economic transformation and ***,the implementation of differentiated regulatory measures for trade in digital services among economies has led to increasingly frequent trade *** paper constructs a regulatory homogeneity network for digital service trade in 60 major economies,and systematically evaluates the structural characteristics of the network and the regulatory homogeneity among economies from 2014 to ***,this paper empirically examines the impact of the partnership characteristics of regulatory homogenization in the network of major economies on their *** analysis of the network structure shows that major economies are more inclined to optimize and simplify existing trade partnerships,and are moving towards more diversified restrictive measures in the regulatory model of digital services trade,which has led to the rise of trade *** empirical text results show that expanding and deepening the regulatory homogeneous partnership of trade in digital services promotes the export of digital services in major *** promotion effect is mainly achieved by reducing the cost of digital service trade and enhancing business *** addition,the export promotion effect of developing regulatory homogenization partnerships is better than that of increasing the openness of digital service trade,and the homogenization of policies between openness and protection is more *** paper provides important implications for coordinating the openness and security of digital services trade:China should actively cooperate with multilateral and bilateral digital service trade partners to jointly build a homogeneous environment for regulatory *** particular,it is necessary to deepen the regulatory homogeneity partnership with Asian and developing economies to expand the infl uence of the“China model”in the global regulation of digital s

关键词： digital service trade regulatory cooperation regulatory homogenization partnerships high-quality trade development

Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation

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Applied mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI Zhi-yu LI Kun CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen school of Mathematical sciences Qufu Normal UniversityQufu 273165China College of mathematics and systems science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this *** oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are *** main method used in this paper is based on Prufer transformation,which is different from the classical ***,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Stability and performance analysis of the compressed Kalman filter algorithm for sparse stochastic systems

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science China(Technological sciences) 2024年第2期67卷 380-394页

作者： LI RongJiang GAN Die XIE SiYu LüJinHu Key Laboratory of systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China school of Mathematical sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun Laboratory Beijing 100049China school of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China school of Automation science and Electrical Engineering Beihang UniversityBeijing 100191China

This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic *** deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)*** algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional ***,the original high-dimensional sparse signals can be well recovered by a reconstruction *** ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and ***,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.

关键词： sparse signal compressed sensing Kalman filter algorithm compressed excitation condition stochastic stability tracking performance