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New black-to-white hole solutions with improved geometry and energy conditions

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 30-43页

作者： Zhongwen Feng Yi Ling Xiaoning Wu Qingquan Jiang school of Physics and Astronomy China West Normal UniversityNanchong 637009China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China school of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of mathematics Academy of Mathematics and System Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China school of Mathematical sciences University of Chinese Academy of SciencesBeijing 100190China

We construct new black-to-white hole solutions which connect the geometry of spacetime at some gluing surface inside the *** continuity of the metric can be guaranteed up to the arbitrary order which is controlled by the power factor *** sort of black-to-white holes is characterized by the sub-Planckian scalar curvature,independent of the mass of black-to-white *** importantly,we show that the energy condition is only violated within a small region near the gluing *** geodesics of particles within the region from black hole to white hole is also *** turns out that the matter falling into the black hole may pass through the center without singularity and come out from the white *** scenario provides novel ideas for understanding the information loss paradox in traditional black hole physics.

关键词： regular black hole energy condition singularity quantum gravity

C^(α)regularity of weak solutions of non-homogeneous ultraparabolic equations with drift terms

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Science China mathematics 2024年第1期67卷 23-44页

作者： Wendong Wang Liqun Zhang school of Mathematical sciences Dalian University of TechnologyDalian 116024China Institute of mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

We consider a class of non-homogeneous ultraparabolic differential equations with singular drift terms arising from some physical models,and prove that weak solutions are H?lder continuous,which are sharp in some sense and also generalize the well-known De Giorgi-Nash-Moser theory to degenerate parabolic equations satisfying the H?rmander hypoellipticity *** new ingredients are manifested in two aspects:on the one hand,for lower-order terms,we exploit a new Sobolev inequality suitable for the Moser iteration by improving the result of Pascucci and Polidoro(2004);on the other hand,we explore the G-function from an early idea of Kruzhkov(1964)and an approximate weak Poincaréinequality for non-negative weak sub-solutions to prove the H?lder regularity.

关键词： ultraparabolic equations Moser iteration Poincare inequality C^a regularity

A survey of fault tolerant consensus in wireless networks

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High-Confidence Computing

High-Confidence Computing 2024年第2期4卷 1-11页

作者： Yifei Zou Li Yang Guanlin Jing Ruirui Zhang Zhenzhen Xie Huiqun Li Dongxiao Yu school of computer Science and Technology Shandong UniversityQingdao 266237China Research Center for mathematics and Interdisciplinary sciences Shandong UniversityQingdao 266237China

Wireless networks have become integral to modern communication systems,enabling the seamless exchange of information across a myriad of ***,the inherent characteristics of wireless channels,such as fading,interference,and openness,pose significant challenges to achieving fault-tolerant consensus within these ***-tolerant consensus,a critical aspect of distributed systems,ensures that network nodes collectively agree on a consistent value even in the presence of faulty or compromised *** survey paper provides a comprehensive overview of faulttolerant consensus mechanisms specifically tailored for wireless *** explore the diverse range of consensus protocols and techniques that have been developed to address the unique challenges of wireless *** paper systematically categorizes these consensus mechanisms based on their underlying principles,communication models,and fault *** investigates how these mechanisms handle various types of faults,including communication errors,node failures,and malicious *** highlights key use cases,such as sensor networks,Internet of Things(IoT)applications,wireless blockchain,and vehicular networks,where fault-tolerant consensus plays a pivotal role in ensuring reliable and accurate data dissemination.

关键词： Consensus Fault-tolerance Byzantine-resilience Wireless networks

Dynamics of Caputo fractional-order SIRV model:The effects of imperfect vaccination on disease transmission

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International Journal of Biomathematics 2024年第4期17卷 267-285页

作者： Auwal Abdullahi Mohd Hafiz Mohd Department of mathematics and computer Science Federal University Kashere Nigeria school of Mathematical sciences Universiti Sains Malaysia 11800 USMPulau PinangMalaysia

Though vaccination protects individuals against many infectious diseases,such protection does not always last forever since a few vaccinated individuals could lose their lifelong immunity and eventually become *** study,therefore,determines the effects of imperfect vaccination and memory index on the spread of diseases through the Caputo fractional-order SIRV(Susceptible-Infected-Recovered-Vaccinated)epidemic *** properties of the new model including the conditions for the existence of a unique solution determined through the fixed-point theory and the conditions for the existence of a positive solution of the model obtained via the Mittag-Leffler function along with the Laplace transformation-are thoroughly ***,our simulation results report that an increase in the imperfect vaccination force increases the population of infected *** the memory effect,the higher“memory”the epidemic system has of past states(which corresponds to decreasing values of fractionalorder parameter),the greater the peaks and magnitudes of infection shaping the epidemiological system dynamics.

关键词： Vaccination model fractional-order model Caputo fractional-order derivative Mittag-Leffer function fixed-point theory

Understanding Human and Machine Interaction from Decision Perspective: An Empirical Study Based on the Game of Go

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Journal of Systems Science & Complexity 2024年第2期37卷 647-667页

作者： ZHAO Ping LI Xuerong WANG Shouyang Academy of mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China school of Mathematical sciences University of Chinese Academy of SciencesBeijing 100190China

The authors aim to interpret human and AI interactions from the decision *** authors decompose the interaction analysis into the following main components in the context of interactions:Individual behavior patterns,interaction relationships,and comprehensive *** authors interpret intertemporal decisions from a physical perspective and employ cross-discipline concepts and methodologies to extract the behavior characteristics of players in the empirical case *** the individual behavior patterns,the authors find that human players prefer short-term periods to AI in *** interaction relationship analysis reveals a dynamic relationship between possible short-term co-movement and nearly counter-movement in the long *** authors apply principal component analysis to descriptive indicators and discover a regular decision *** main behavior pattern of players in the game of Go is switching between careful and daring *** differences in the decision hierarchies imply a discrepancy of patience between humans and AI.

关键词： Coherence analysis decision hierarchy machine behaviour multitaper spectral analysis

One-step hydrothermal synthesis of Cit-NaYbF_(4):Er^(3+)nanocrystals with enhanced red upconversion emission for in vivo fluorescence molecular tomography

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Journal of Rare Earths 2024年第1期42卷 36-45,I0002页

作者： Xiaoli Luo Qichen Chen Hongbo Guo Heng Zhang Xiaowei He Wu Zhao school of mathematics and computer Science Ningxia Normal UniversityGuyuan756099China school of Information Science and Technology Northwest UniversityXi'an710127China

Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical *** this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was *** introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce *** fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 ***,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio *** laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell *** addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa *** imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and ***,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.

关键词： Hydrothermal method Fe^(2+)ion doping Tuning size Nanoprobes Fluorescence imaging Rare earths

Effects of asymmetric coupling and boundary on the dynamic behaviors of a random nearest neighbor coupled system

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Chinese Physics B 2024年第6期33卷 309-322页

作者：徐玲姜磊 school of Mathematical sciences Sichuan Normal UniversityChengdu 610066China school of mathematics and Statistics Linyi UniversityLinyi 276000China

This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined ***, the study derivative analytical stability and synchronization conditions for the asymmetrically coupled system in an unconfined space, which are then validated through numerical simulations. Simulation results show that asymmetric coupling has a significant impact on synchronization conditions. Moreover, it is observed that irrespective of whether the system is confined, an increase in coupling asymmetry leads to a hastened synchronization pace. Additionally, the study examines the effects of boundaries on the system's collective behaviors via numerical experiments. The presence of boundaries ensures the system's stability and synchronization, and reducing these boundaries can expedite the synchronization process and amplify its effects. Finally, the study reveals that the system's output amplitude exhibits stochastic resonance as the confined boundary size increases.

关键词： asymmetric coupled confined space synchronization stochastic resonance stability

The Non-inclusion Diagnosability of Hypercubes Under the PMC Model

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Journal of the Operations Research Society of China 2024年第2期12卷 478-484页

作者： Mei-Jie Ma Min Xu Tong-Tong Ding Xiang-Jun Li Qiang Zhu school of mathematics and Statistics Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353ShandongChina school of Mathematical sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875China school of Information and mathematics Yangtze UniversityJingzhou 434023HubeiChina school of mathematics and Statistics XiDian UniversityXi'an 710071ShaanXiChina

Diagnosability of a multiprocessor system is an important measure of the reliability of interconnection ***-level diagnosis is a primary strategy to identify the faulty processors in a multiprocessor *** on a sound assumption proposed by Zhu et ***,we proposed a new diagnosability named non-inclusion diagnosability and showed that the non-inclusion diagnosability t_(N)(Q_(n))of the hypercube under the PMC model is *** is,assume that if two vertex sets F_(1) and F_(2) are both consistent with a syndrome and F_(1)C F_(2),then F_(2) is not the faulty set which we are looking for;the faulty set F is 1-step diagnosable if|F|≤2n-2 in Q_(n) under the PMC model.

关键词： Interconnection network Diagnosability Hypercube PMC model

THE LIMIT CYCLE BIFURCATIONS OF A WHIRLING PENDULUM WITH PIECEWISE SMOOTH PERTURBATIONS

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Acta Mathematica Scientia 2024年第3期44卷 1115-1144页

作者：杨纪华 school of mathematics and computer Science Ningxia Normal UniversityGuyuan756000China Ningxia Basic Science Research Center of mathematics Yinchuan750000China

This paper deals with the problem of limit cycles for the whirling pendulum equation x=y,y=sin x(cosx-r)under piecewise smooth perturbations of polynomials of cos x,sin x and y of degree n with the switching line x=*** upper bounds of the number of limit cycles in both the oscillatory and the rotary regions are obtained using the Picard-Fuchs equations,which the generating functions of the associated first order Melnikov functions ***,the exact bound of a special case is given using the Chebyshev *** the end,some numerical simulations are given to illustrate the existence of limit cycles.

关键词： whirling pendulum limit cycle Melnikov function Picard-Fuchs equation Chebyshev system