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Limit Theorems for Critical Galton-Watson Processes with Immigration Stopped at Zero

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Acta Mathematica Sinica,English Series 2024年第2期40卷 435-450页

作者： dou dou LI Mei ZHANG Xian Yu ZHANG College of Statistics and Data Science Faculty of ScienceBeijing University of TechnologyBeijing 100124P.R.China Laboratory of mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,we consider a critical Galton-Watson branching process with immigration stopped at zero *** precise estimation on the probability generating function of the n-th population are obtained,and the tail prob... 详细信息

关键词： Branching immigration critical life period limit theorems

Progress in neurorehabilitation research and the support by the National Natural Science Foundation of China from 2010 to 2022

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Neural Regeneration Research 2024年第1期19卷 226-232页

作者： Qian Tao Honglu Chao Dong Fang dou dou School of Medicine Jinan UniversityGuangzhouGuangdong ProvinceChina School of Health and Life Science University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina department of Health Sciences National Natural Science Foundation of ChinaBeijingChina department of Neurosurgery The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina

The National Natural Science Foundation of China is one of the major funding agencies for neuro rehabilitation research in *** study reviews the frontier directions and achievements in the field of neurorehabilitation in China and wo *** used data from the Web of Science Core Collection(WoSCC) database to analyze the publications and data provided by the National Natural Science Foundation of China to analyze funding *** addition,the prospects for neurorehabilitation research in China are *** 2010 to 2022,a total of 74,220 publications in neurorehabilitation were identified,with there being an overall upward *** this period,the National Natural Science Foundation of China has funded 476 research projects with a total funding of 192.38 million RMB to support neuro rehabilitation research in *** the support of the National Natural Science Foundation of China,China has made some achievements in neurorehabilitation *** related to neurorehabilitation is believed to be making steady and significant progress in China.

关键词： brain computer interface invasive neuromodulation National Natural Science Foundation of China(NSFC) neuroreha bilitation non-invasive brain stimulation publication rehabilitation robotics virtual reality

A novel three-inflection-point sliding mode control framework for forward-tilting morphing aerospace vehicle with performance constraints and actuator faults

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Chinese Journal of Aeronautics 2024年第8期37卷 293-310页

作者： Xinkai LI Lei dou Hongli ZHANG Yue MENG School of Electrical Engineering Xinjiang UniversityUrumqi 830047China

A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator *** accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is *** convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is *** global asymptotic stability of the system is demonstrated using a strict mathematical *** effectiveness and superiority of the proposed control scheme are proven by simulation experiments.

关键词： Morphing aerospace vehicle Actuator faults Immersion and invariance Three-inflection-point sliding mode control Prescribed performance control

Modeling Long- and Short-Term Service Recommendations with a Deep Multi-Interest Network for Edge Computing

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Tsinghua Science and Technology 2024年第1期29卷 86-98页

作者： Rui Yuan Shunmei Meng Ruihan dou Xinna Wang department of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210056China Faculty of mathematics University of WaterlooWaterloo N2L 3G1Canada

Edge computing platforms enable application developers and content providers to provide context-aware services(such as service recommendations)using real-time wireless access network *** to recommend the most suitable candidate from these numerous available services is an urgent ***-through rate(CTR)prediction is a core task of traditional service ***,many existing service recommender systems do not exploit user mobility for prediction,particularly in an edge computing *** this paper,we propose a model named long and short-term user preferences modeling with a multi-interest network based on user *** uses a logarithmic network to capture multiple interests in different fields,enriching the representations of user short-term *** terms of long-term preferences,users'comprehensive preferences are extracted in different periods and are fused using a nonlocal *** experiments on three datasets demonstrate that our model relying on user mobility can substantially improve the accuracy of service recommendation in edge computing compared with the state-of-the-art models.

关键词： recommender system logarithmic network nonlocal network

Optimization-based mode selection scheme for OAM millimeter wave system in the off-axis misalignment case

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Digital Communications and Networks 2024年第1期10卷 101-108页

作者： Haie dou Lei Wang Bin Kang Baoyu Zheng Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China

Millimeter-wave transmission combined with Orbital Angular Momentum(OAM)has the advantage of reducing the loss of beam power and increasing the system ***,to fulfill this advantage,the antennas at the transmitter and receiver must be parallel and coaxial;otherwise,the accuracy of mode detection at the receiver can be seriously *** this paper,we design an OAM millimeter-wave communication system for overcoming the above ***,the first contribution is that the power distribution between different OAM modes and the capacity of the system with different mode sets are analytically derived for performance *** second contribution lies in that a novel mode selection scheme is proposed to reduce the total interference between different *** results show that system performance is less affected by the offset when the mode set with smaller modes or larger intervals is selected.

关键词： Orbital angular momentum Millimeter wave Off-axis misalignment Mode selection Capacity

Engineering S-scheme W_(18)O_(49)/ZnIn_(2)S_(4)heterojunction by Co_(x)P nanoclusters for enhanced charge transfer capability and solar hydrogen evolution

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Nano Research 2024年第9期17卷 8095-8103页

作者： Xiaojie Liu Erkang Liu Zixian Wang Wen Zhang Mingyu dou Hua Yang Changhua An Dacheng Li Jianmin dou Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252059China Tianjin Key Laboratory of Organic Solar Cell and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin Key Laboratory of Advanced Functional Porous MaterialsInstitute for New Energy Materials and Low-Carbon TechnologiesTianjin University of TechnologyTianjin 300384China Institute of Powder Metallurgy and Advanced Ceramics School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Enhancement of the light-absorption response and utilization of the photogenerated carriers represent a robust strategy for the design of high-performance *** this work,grafting Co_(x)P nanoclusters onto S-scheme heterojunction of W18O49/ZnIn2S4(WO/ZIS-CoxP)with strong response to the ultraviolet-visible-near infrared ray(UV-vis-NIR)region has been achieved,which possesses efficient electron-transfer-channel,and boosts charge-separation and transport *** as-prepared WO/ZIS-Co_(x)P yields an impressive solar-driven hydrogen production rate of 45 mmol·g^(-1)·h^(-1).The increased photocatalytic performance is attributed to the synergistic effect of the composite catalyst:(1)The local surface plasmon resonance-induced“hot electron”injection of W_(18)O_(49)significantly increases the electron density;(2)the engineered S-scheme directional electron transfer promotes charge separation and enhances the reducing capability of photoexcited electrons;and(3)Co_(x)P as electron-trap site for accelerating surface proton reduction *** work provides a platform to impart nonprecious co-catalyst for engineering S-scheme heterojunction,serving a class of efficient solar-driven photocatalyst towards hydrogen production.

关键词： hydrogen cocatalyst photocatalysis S-scheme hot electron

Spatiotemporal Prediction of Urban Traffics Based on Deep GNN

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Computers, Materials & Continua 2024年第1期78卷 265-282页

作者： Ming Luo Huili dou Ning Zheng School of Computer Science Hangzhou Dianzi UniversityHangzhou310018China Zhejiang Institute of Communications Hangzhou310012China School of Cyberspace Security Hangzhou Dianzi UniversityHangzhou310018China

Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of traffic *** well as to fulfil both long-termand short-termprediction objectives,a better representation of the temporal dependency and global spatial correlation of traffic data is *** order to do this,the Spatiotemporal Graph Neural Network(S-GNN)is proposed in this research as amethod for traffic *** S-GNN simultaneously accepts various traffic data as inputs and investigates the non-linear correlations between the *** terms of modelling,the road network is initially represented as a spatiotemporal directed graph,with the features of the samples at the time step being captured by a convolution *** order to assign varying attention weights to various adjacent area nodes of the target node,the adjacent areas information of nodes in the road network is then aggregated using a graph *** data is output using a fully connected layer at the *** findings show that S-GNN can improve short-and long-term traffic prediction accuracy to a greater extent;in comparison to the control model,the RMSE of S-GNN is reduced by about 0.571 to 9.288 and the MAE(Mean Absolute Error)by about 0.314 to *** experimental results on two real datasets,Pe MSD7(M)and PEMS-BAY,also support this claim.

关键词： Urban traffic traffic temporal correlation GNN prediction

Quantized Decoders that Maximize Mutual Information for Polar Codes

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China Communications 2024年第7期21卷 125-134页

作者： Zhu Hongfei Cao Zhiwei Zhao Yuping Li dou School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

In this paper,we innovatively associate the mutual information with the frame error rate(FER)performance and propose novel quantized decoders for polar *** on the optimal quantizer of binary-input discrete memoryless channels(BDMCs),the proposed decoders quantize the virtual subchannels of polar codes to maximize mutual information(MMI)between source bits and quantized *** nested structure of polar codes ensures that the MMI quantization can be implemented stage by *** results show that the proposed MMI decoders with 4 quantization bits outperform the existing nonuniform quantized decoders that minimize mean-squared error(MMSE)with 4 quantization bits,and yield even better performance than uniform MMI quantized decoders with 5 quantization ***,the proposed 5-bit quantized MMI decoders approach the floating-point decoders with negligible performance loss.

关键词： maximize mutual information polar codes quantization successive cancellation decoding

Solvent effects on Diels-Alder reaction in ionic liquids:A reaction density functional study

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Chinese Journal of Chemical Engineering 2024年第2期66卷 180-188页

作者： Zijiang dou Weiqiang Tang Peng Xie Shuangliang Zhao Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and ***,the underlying microscopic mechanism remains *** this work,the multiscale reaction density functional theory is applied to explore the effect of 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM][PF_(6)])solvent on the reaction of cyclopentadiene(CP)with acrolein,methyl acrylate,or *** analyzing the free energy landscape during the reaction,it is found that the polarization effect has a relatively small influence,while the solvation effect makes both the activation free energy and reaction free energy *** addition,the rearrangement of local solvent structure shows that the cation spatial distribution responds more evidently to the reaction than the anion,and this indicates that the cation plays a dominant role in the solvation effect and so as to affect the reaction rates and selectivity of the DA reactions.

关键词： Solvent effect Ionic liquids Diels-Alder reaction Reaction density functional theory