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Science China Mathematics 2017年第4期60卷 735-744页

作者： yue chao School of Economics and Trade Zhengzhou University of Aeronautics Zhengzhou 450015 China

We consider the mean-square stability of the so-called improved split-step theta method for stochastic differential equations. First, we study the mean-square stability of the method for linear test equations with real parameters. When 0 ≥ 3/2, the improved split-step theta methods can reproduce the mean-square stability of the linear test equations for any step sizes h 〉 0. Then, under a coupled condition on the drift and diffusion coefficients, we consider exponential mean-square stability of the method for nonlinear non-autonomous stochastic differential equations. Finally, the obtained results are supported by numerical experiments.

关键词： stochastic differential equations mean-square stability improved split-step theta methods expo-nential mean-square stability

Future forestation in China should aim to align the temporal service window of the forest carbon sink with the“carbon neutrality”strategy

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Science China Earth Sciences 2023年第12期66卷 2971-2976页

作者： Hao XU chao yue Shilong PIAO College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

*** Carbon sequestration in forest ecosystems worldwide dominates the current global terrestrial carbon sink,offsetting approximately 26% of global anthropogenic carbon emissions annually(Pan et al.,2011).

关键词： service annually forest

Resource allocation for D2D-assisted haptic communications

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Digital Communications and Networks 2024年第1期10卷 63-74页

作者： Yan Wu chao yue Yang Yang Liang Ao College of Telecommunication Engineering Army Engineering University of PLANanjing210000China

Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous *** the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic *** particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D ***,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet ***,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available *** this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error ***,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D *** game theory is introduced to solve the problem with low ***,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash *** results demonstrate the superiority of the proposed learning algorithm.

关键词： Haptic communications D2D Power control Contention-based access Potential game

Perspectives on the role of terrestrial ecosystems in the ‘carbon neutrality' strategy

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Science China Earth Sciences 2022年第6期65卷 1178-1186页

作者： Shilong PIAO chao yue Jinzhi DING Zhengtang GUO College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Chinese government has made a strategic decision to reach ‘carbon neutrality' before 2060. China's terrestrial ecosystem carbon sink is currently offsetting 7–15% of national anthropogenic emissions and has received widespread attention regarding its role in the ‘carbon neutrality' strategy. We provide perspectives on this question by inferring from the fundamental principles of terrestrial ecosystem carbon cycles. We first elucidate the basic ecological theory that, over the long-term succession of ecosystem without regenerative disturbances, the carbon sink of a given ecosystem will inevitably approach zero as the ecosystem reaches its equilibrium state or climax. In this sense, we argue that the currently observed global terrestrial carbon sink largely emerges from the processes of carbon uptake and release of ecosystem responding to environmental changes and, as such, the carbon sink is never an intrinsic ecosystem function. We further elaborate on the long-term effects of atmospheric CO_(2) changes and afforestation on China's terrestrial carbon sink: the enhancement of the terrestrial carbon sink by the CO_(2) fertilization effect will diminish as the growth of the atmospheric CO_(2) slows down, or completely stops, depending on international efforts to combat climate change, and carbon sinks induced by ecological engineering, such as afforestation, will also decline as forest ecosystems become mature and reach their late-successional stage. We conclude that terrestrial ecosystems have nonetheless an important role to play to gain time for industrial emission reduction during the implementation of the ‘carbon neutrality' strategy. In addition, science-based ecological engineering measures including afforestation and forest management could be used to elongate the time of ecosystem carbon sink service. We propose that the terrestrial carbon sink pathway should be optimized, by addressing the questions of ‘when' and ‘where' to plan afforestation projects, in

关键词： Carbon neutrality Terrestrial ecosystem carbon sink CO_(2)fertilization effect Afforestation Carbon sink pathway

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Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： chao-yue Sun Wen Li Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

The programmable CPG model based on Matsuoka oscillator and its application to robot locomotion

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第3期11卷 22-39页

作者： Qiang Lu Zhaochen Zhang chao yue College of Medical Information Engineering Shandong First Medical Universityand Shandong Academy of Medical SciencesTaian 271000Shandong ProvinceP.R.China

The central pattern generator(CPG)is an important functional unit in the spinal cord which can produce rhythmic signals to control ***,there has been a growing interest in programmable central pattern generators(PCPG).In this paper,a new PCPG oscillator and a generic PCPG model based on the Matsuoka oscillator are *** perturbation method is used to determine the convergence of the generic PCPG *** sine signal,the mix signal and chaotic signals are provided as inputs to the model,and the simulation results show that the generic PCPG can learn arbitrary periodic *** this paper,the generic PCPGs are allocated at each joint of the compass-like and the three-link robots and their outputs are chosen as joint position *** simulations show that the generic PCPG can be used to control robot locomotion *** contributions of this paper are as follows:(1)A new PCPG oscillator based on the Matsuoka oscillator is presented as a beneficial enhancement to the PCPG oscillators.(2)A generic PCPG model is built comprising three PCPG *** can learn any periodic input *** findings are a significant contribution to generic PCPG research.

关键词： Programmable central pattern generator rhythmic oscillator robot locomotion

Passive Localization of Multiple Sources Using Joint RSS and AOA Measurements in Spectrum Sharing System

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China Communications 2021年第12期18卷 65-80页

作者： Kang Li Yutao Jiao Yehui Song Jinghua Li chao yue College of Communication Engineering Army Engineering University of PLANanjing 210007China

In spectrum sharing systems,locating mul-tiple radiation sources can efficiently find out the in-truders,which protects the shared spectrum from ma-licious jamming or other unauthorized ***-pared to single-source localization,simultaneously lo-cating multiple sources is more challenging in prac-tice since the association between measurement pa-rameters and source nodes are not ***-over,the number of possible measurements-source as-sociations increases exponentially with the number of sensor *** is crucial to discriminate which measurements correspond to the same source before *** this work,we propose a central-ized localization scheme to estimate the positions of multiple ***,we develop two computa-tionally light methods to handle the unknown RSS-AOA measurements-source association *** method utilizes linear coordinate conversion to com-pute the minimum spatial Euclidean distance sum-mation of *** method exploits the long-short-term memory(LSTM)network to clas-sify the measurement ***,we propose a weighted least squares(WLS)approach to obtain the closed-form estimation of the positions by linearizing the non-convex localization *** re-sults demonstrate that the proposed scheme could gain sufficient localization accuracy under adversarial sce-narios where the sources are in close proximity and the measurement noise is strong.

关键词： multiple sources localization passive lo-calization received signal strength(RSS) angle of ar-rival(AOA) measurements-source association

Specific Emitter Identification for IoT Devices Based on Deep Residual Shrinkage Networks

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China Communications 2021年第12期18卷 81-93页

作者： Peng Tang Yitao Xu Guofeng Wei Yang Yang chao yue College of Communications Engineering Army Engineering University of PLANanjing 210007China

Specific emitter identification can distin-guish individual transmitters by analyzing received signals and extracting inherent features of hard-ware *** extraction is a key part of traditional machine learning-based methods,but manual extrac-tion is generally limited by prior professional *** the same time,it has been noted that the per-formance of most specific emitter identification meth-ods degrades in the low signal-to-noise ratio(SNR)*** deep residual shrinkage network(DRSN)is proposed for specific emitter identification,particularly in the low *** soft threshold can preserve more key features for the improvement of performance,and an identity shortcut can speed up the training *** collect signals via the receiver to create a dataset in the actual *** DRSN is trained to automatically extract features and imple-ment the classification of *** results show that DRSN obtains the best accuracy un-der different SNRs and has less running time,which demonstrates the effectiveness of DRSN in identify-ing specific emitters.

关键词： specific emitter identification IoT de-vices deep learning soft threshold deep residual shrinkage networks

Visual Superordinate Abstraction for Robust Concept Learning

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Machine Intelligence Research 2023年第1期20卷 79-91页

作者： Qi Zheng chao-yue Wang Dadong Wang Da-Cheng Tao University of Sydney Sydney 2008Australia JD Explore Academy Beijing 100176China DATA61 Commonwealth Scientific and Industrial Research OrganisationSydney 2122Australia

Concept learning constructs visual representations that are connected to linguistic semantics, which is fundamental to vision-language tasks. Although promising progress has been made, existing concept learners are still vulnerable to attribute perturbations and out-of-distribution compositions during inference. We ascribe the bottleneck to a failure to explore the intrinsic semantic hierarchy of visual concepts, e.g., {red, blue,···} ∈“color” subspace yet cube ∈“shape”. In this paper, we propose a visual superordinate abstraction framework for explicitly modeling semantic-aware visual subspaces(i.e., visual superordinates). With only natural visual question answering data, our model first acquires the semantic hierarchy from a linguistic view and then explores mutually exclusive visual superordinates under the guidance of linguistic hierarchy. In addition, a quasi-center visual concept clustering and superordinate shortcut learning schemes are proposed to enhance the discrimination and independence of concepts within each visual superordinate. Experiments demonstrate the superiority of the proposed framework under diverse settings, which increases the overall answering accuracy relatively by 7.5% for reasoning with perturbations and 15.6% for compositional generalization tests.

关键词： Concept learning visual question answering weakly-supervised learning multi-modal learning curriculum learning

The effect of non-storm time substorms on the ring current dynamics

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Earth and Planetary Physics 2021年第3期5卷 251-258页

作者： EunJin Jang chao yue QiuGang Zong SuiYan Fu HaoBo Fu Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

During geomagnetically active times such as geomagnetic storms,large amounts of energy can be released into the Earth’s magnetosphere and change the ring current *** studies showed that significant enhancement of the ring current was related to geomagnetic storms,while few studies have examined substorm effects on ring current *** this study,we examine the ring current variation during non-storm time(SYM-H>−50 nT)substorms,especially during super-substorms(AE>1000 nT).We perform a statistical analysis of ring current plasma pressure and number flux of various ion species under different substorm conditions,based on Van Allen Probe *** plasma pressure and ion fluxes of the ring current increased dramatically during supersubstorms,while little change was observed for substorms with AE<1000 *** results shown in this study indicate that a non-storm time super-substorm may also have a significant contribution to the ring current.

关键词： super-substorms ring current ion fluxes