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Study of Turing patterns in a SI reaction-diffusion propagation system based on network and non-network environments

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International Journal of Biomathematics 2024年第1期17卷 199-225页

作者： yuxuan Tang Shuling shen Linhe Zhu School of Mathematical Sciences Jiangsu University Zhenjiang212013P.R.China Department of Stomatology Afiliated Hospital of Jiangsu University Zhenjiang 210008P.R.China

The study of rumor propagation dynamics is of great significance to reduce.false news and ensure the authenticity of news information.In this paper,a SI reaction-diffusion rumor propagation model with nonlinear saturation incidence is studied.First,through stability analysis,we obtain the conditions for the existence and local stability of the positive equilibrium point.By selecting suitable variable as the control parameter,the critical value of Turing bifurcation and the existence theorem of Turing bifurcation are obtained.Then,using the above theorem and multi-scale standard analysis,the expression of amplitude equation around Turing bifurcation point is obtained.By analyzing the amplitude equation,different types of Turing pattern are divided such as uniform steady-state mode,hexagonal mode,stripe mode and mixed structure mode.Further,in the numerical simulation part,by observing different patterns corresponding to different values of control variable,the correctness of the theory is verified.Finally,the effects of different network structures on patterns are investigated.The results show that there are significant differences in the distribution of users on different network structures.

关键词： Reaction-diffusion system rumor propagation amplitude equation Turing pattern

Linear-fitting-based recursive filtering for nonlinear systems under encoding-decoding mechanism

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Science China(Information Sciences) 2024年第5期67卷 183-196页

作者： Bo JIANG Hongli DONG Zhiwei GAO Yuxuan Shen Fan YANG Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Sanya Offshore Oil & Gas Research Institute Northeast Petroleum University School of Electrical & Information Engineering Northeast Petroleum University

This paper deals with a recursive filtering problem for a class of discrete time-varying nonlinear networked systems with the encoding-decoding mechanism. The linear fitting method is introduced to handle the nonlinearity. An encoding-decoding mechanism is constructed to describe the data transmission process in wireless communication networks(WCNs). To be specific, the measurement outputs are mapped by a quantizer to unique codewords for transmission in WCNs. Then, the codewords are decoded by the decoder to recover the measurement outputs which are sent to the filter. The processing/encoding delay and network delay have been considered. Firstly, on the premise that the upper bound of the filtering error covariance is minimum, the appropriate filtering gain is calculated. Then, the mean square exponential boundedness of the filtering error is analyzed. Finally, two simulation examples are presented to verify the effectiveness of the proposed algorithm.

关键词： encoding-decoding mechanism uniform quantizer linear fitting networked systems recursive filtering

Protocol-Based Non-Fragile State Estimation for Delayed Recurrent Neural Networks Subject to Replay Attacks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 249-251页

作者： Fan Yang Hongli Dong Yuxuan Shen Xuerong Li Dongyan Dai the Artificial Intelligence Energy Research Institute Northeast Petroleum UniversityDaqing 163318 the Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum UniversityDaqing 163318 the Sanya Offshore Oil&Gas Research Institute Sanya 572025China IEEE

Dear Editor, This letter focuses on the protocol-based non-fragile state estimation problem for a class of recurrent neural networks(RNNs). With the development of communication technology, the networked systems have ... 详细信息

关键词： network communication estimation

Isolation and identification of four pathogenic bacterial strains from edible snake(Elaphe carinata and Ptyas mucosus)farms with pneumonia in China

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Animal Diseases 2023年第1期3卷 56-61页

作者： Ying Xia Siyu Long yuxuan Peng Songkang Qin Yaoqin shen College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070People’s Republic of China

This report describes an outbreak and treatment of pneumonia and enteritis in a snake farm with more than 3000 snakes containing Elaphe carinata(one-year-old)and Ptyas mucosus(three-month-old)seedlings in Huanggang,Hubei,China.Gentamicin was used once in the early stage as treatment,administered orally with water or feed by owners,but mortality increased.Lobar pneumonia was confirmed by dissection and histopathology in infected snakes.Four main pathogenic bacteria were isolated and identified with culture and 16S rRNA sequencing:Staphylococcus sciuri,Salmonella enteritis,Vagococcus fluvialis and Providencia vermicola.Drug susceptibility tests were performed,and amikacin,gentamicin and cefitriaxone were chosen accordingly.After two rounds of treatment,the clinical signs for Elaphe carinata were under control,and the mortality was close to 0%after treatment.However,treatments for Ptyas mucosus seedlings did not work well,potentially because of poor administration technique and weak body condition.

关键词： Staphylococcus sciuri Antimicrobial resistant Edible snakes Dermatitis

Changes in tropospheric ozone levels over the Three Representative Regions of China observed from space by the Tropospheric Emission Spectrometer (TES), 2005-2010

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Chinese Science Bulletin 2012年第22期57卷 2865-2871页

作者： shen LuLu WANG yuxuan Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Institute for Global Change StudiesTsinghua University Beijing 100084 China

Tropospheric ozone observations over China from 2005 to 2010 at three pressure levels (484,681 and 825 hPa) from the Tropospheric Emission Spectrometer on board the NASA Aura satellite have been analyzed.Fourier Transform analysis revealed the trends and seasonality of regionally-averaged,monthly-mean ozone concentrations over western,northern and southern China.Significant increases in ozone levels are found over all three regions at 464 hPa and the rate of increase is fastest over northern China,reaching 0.89±0.059 nL/(La).At 681 hPa,ozone shows increases over northern and western China,at a rate of 0.57± 0.065 nL/(La) and 0.41±0.041 nL/(La) respectively,but is constant over southern China.At 825 hPa,ozone increases at a rate of 0.36±0.074 nL/(La) over northern China,while decreasing over southern China at a rate of 0.21±0.061 nL/(La).Over the three regions,ozone levels are generally higher in summer and lower in winter.Over southern China at all three pressure levels and northern China at the 825 hPa level,ozone shows double peaks occurring in spring and autumn as a result of the combined effects of atmospheric chemistry and global transport.This work provides a useful observational dataset and tools for future analysis of changes in tropospheric ozone over China.

关键词：发射光谱仪中国地区臭氧水对流层三个代表 TES 空间观傅里叶变换分析

Identifying the enhancement mechanism of Al/MoO_(3) reactive multilayered films on the ignition ability of semiconductor bridge using a one-dimensional gas-solid two-phase flow model

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Defence Technology（防务技术） 2024年第3期33卷 168-179页

作者： Jianbing Xu yuxuan Zhou Yun shen Yueting Wang Yinghua Ye Ruiqi shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing 210094China Institute of Space Propulsion Nanjing University of Science and TechnologyNanjing 210094China

Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.

关键词： Ignition enhancement mechanism 1D gas-solid two-phase flow Al/MoO_(3)reactive multilayered films Semiconductor bridge Miniaturized ignition device

Performance analysis of frequency‑mixed PPP‑RTK using low‑cost GNSS chipset with different antenna configurations

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Satellite Navigation 2023年第3期4卷 54-71页

作者： Xingxing Li Hailong Gou Xin Li Zhiheng shen Hongbo Lyu yuxuan Zhou Hao Wang Qian Zhang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079HubeiChina Hubei Luojia Laboratory Wuhan University129 Luoyu RoadWuhan 430079HubeiChina Tianjin Navigation Instrument Research Institute 268 Dingzigu 1St RoadTianjin 300130China Meituan 6 Wangjing East RoadChaoyang DistrictBeijingChina

Low-cost Global Navigation Satellite System(GNSS)devices offer a cost-effective alternative to traditional GNSS systems,making GNSS technology accessible to a wider range of applications.Nevertheless,low-cost GNSS devices often face the challenges in effectively capturing and tracking satellite signals,which leads to losing the observations at certain frequencies.Moreover,the observation peculiarities of low-cost devices are in contradistinction to those of traditional geodetic GNSS receivers.In this contribution,a low-cost PPP-RTK model that considers the unique characteristics of different types of measurements is developed and its performance is fully evaluated with u-blox F9P receivers equipped with three distinctive antenna configurations:vertical dipole,microstrip patch,and helix antennas.Several static and kinematic experiments in different scenarios are conducted to verify the effectiveness of the proposed method.The results indicate that the mixed-frequency PPP-RTK model outperforms the traditional dual-frequency one with higher positioning accuracy and fixing percentage.Among the three low-cost antennas tested,the vertical dipole antenna demonstrates the best performance under static conditions and shows a comparable performance as geodetic antennas with a positioning accuracy of 0.02 m,0.01 m and 0.07 m in the east,north,and up components,respectively.Under low-speed kinematic scenarios,the helix antenna outperforms the other two with a positioning accuracy of(0.07 m,0.07 m,0.34 m).Furthermore,the helix antenna is also proved to be the best choice for vehicle navigation with an ambiguity fixing rate of over 95%and a positioning accuracy of(0.13 m,0.14 m,0.36 m).

关键词： PPP-RTK Low-cost device Rapid ambiguity resolution Centimeter-level positioning accuracy Performance assessment

Low-temperature Li-S batteries enabled by all amorphous con version process of organosulfur cathode

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Journal of Energy Chemistry 2022年第1期31卷 496-502,I0013页

作者： Zhenkang Wang Xiaowei shen Sijie Li yuxuan Wu Tingzhou Yang Jie Liu Tao Qian Chenglin Yan College of Energy Key Laboratory of Advanced Carb on Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou 215006JiangsuChina College of Chemistry and Chemical Engineering.Nantong University Seyuan 9Nantong 226000JiangsuChina

The high degree of crystallinity of discharging in termediates of Li-S batteries(Li_(2)S_(2)/Li_(2)S)causes a severe capacity attenuation at low temperatures.Herein,a sulfur-rich polymer is fabricated,which enables all the discharging in termediates to exist in an amorphous state without long-range order,promoti ng the substantial conversion of discharging intermediates and enhancing Li-S batteries'performance at low temperatures greatly.This cathode material exhibits excellent performance both at room and low temperatures.Even under an extremely low temperature(-40℃),the discharge capacity can remain 67% of that at room temperature.Besides,in-situ UV/Vis spectroscopy and density functional theory calculations reveal that this organosulfur cathode undergoes a new mechanism during discharge.Li_(2)S_(6) and Li_(2)S_(3) are the primary discharging intermediates that are quite different from conventional Li-S batteries.These results provide a new directi on for a broader range of applications of Li-S batteries.

关键词： Low temperature Organosulfur polymers Li-S battery Crystallinity

Gait Recognition via Cross Walking Condition Constraint

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Computers, Materials & Continua 2021年第9期68卷 3045-3060页

作者： Runsheng Wang Hefei Ling Ping Li yuxuan Shi Lei Wu Jialie shen HuaZhong University of Science and Technology Wuhan430074China Queen’s University BelfastBT71NNUK

Gait recognition is a biometric technique that captures human walking pattern using gait silhouettes as input and can be used for long-term recognition.Recently proposed video-based methods achieve high performance.However,gait covariates or walking conditions,i.e.,bag carrying and clothing,make the recognition of intra-class gait samples hard.Advanced methods simply use triplet loss for metric learning,which does not take the gait covariates into account.For alleviating the adverse influence of gait covariates,we propose cross walking condition constraint to explicitly consider the gait covariates.Specifically,this approach designs center-based and pair-wise loss functions to decrease discrepancy of intra-class gait samples under different walking conditions and enlarge the distance of inter-class gait samples under the same walking condition.Besides,we also propose a video-based strong baseline model of high performance by applying simple yet effective tricks,which have been validated in other individual recognition fields.With the proposed baseline model and loss functions,our method achieves the state-of-the-art performance.

关键词： Gait recognition metric learning cross walking condition constraint gait covariates