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Stability of stochastic switched epidemic systems with discrete or distributed time delay

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Journal of Systems Engineering and Electronics 2014年第4期25卷 660-670页

作者： Xiaoying Meng Feiqi deng Institute of Systems Engineering South China University of Technology School of Statistics and Mathematics Zhongnan University of Economics and Law

Stochastic switched epidemic systems with a discrete or distributed time delay are constructed and investigated. By the Lyapunov method and lto＇s differential rule, the existence and uniqueness of global positive solution of each system is proved. And stability conditions of the disease-free equilibrium of the systems are obtained. Numerical simulations are presented to illustrate the results.

关键词： stochastic switched epidemic system discrete timedelay distributed time delay stochastically stable Lyapunov functional.

Chebyshev spectral variational integrator and applications

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Applied Mathematics and Mechanics(English Edition) 2020年第5期41卷 753-768页

作者： Zhonggui YI Baozeng YUE Mingle deng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China China Academy of Space Technology Beijing 100094China

The Chebyshev spectral variational integrator(CSVI) is presented in this paper. Spectral methods have aroused great interest in approximating numerically a smooth problem for their attractive geometric convergence rates. The geometric numerical methods are praised for their excellent long-time geometric structure-preserving *** to the generalized Galerkin framework, we combine two methods together to construct a variational integrator, which captures the merits of both methods. Since the interpolating points of the variational integrator are chosen as the Chebyshev points,the integration of Lagrangian can be approximated by the Clenshaw-Curtis quadrature rule, and the barycentric Lagrange interpolation is presented to substitute for the classic Lagrange interpolation in the approximation of configuration variables and the corresponding derivatives. The numerical float errors of the first-order spectral differentiation matrix can be alleviated by using a trigonometric identity especially when the number of Chebyshev points is large. Furthermore, the spectral variational integrator(SVI) constructed by the Gauss-Legendre quadrature rule and the multi-interval spectral method are carried out to compare with the CSVI, and the interesting kink phenomena for the Clenshaw-Curtis quadrature rule are discovered. The numerical results reveal that the CSVI has an advantage on the computing time over the whole progress and a higher accuracy than the SVI before the kink position. The effectiveness of the proposed method is demonstrated and verified perfectly through the numerical simulations for several classical mechanics examples and the orbital propagation for the planet systems and the Solar system.

关键词： geometric numerical method spectral method variational integrator Clenshaw-Curtis quadrature rule barycentric Lagrange interpolation orbital propagation

An ECR-PCR rule for fusion of evidences defined on a non-exclusive framework of discernment

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Chinese Journal of Aeronautics 2022年第8期35卷 179-192页

作者： Xinyang deng Yebi CUI Wen JIANG School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China

In the research of uncertain information processing,Dempster-Shafer Theory(DST)provides a framework for dealing with uncertain information,where evidence is defined on a Frame of Discernment(FOD)consisting of mutually exclusive ***,the requirement of exclusiveness on FOD sometimes is not satisfied,as shown in Dezert-Smarandache Theory(DSm T),a derivative of *** DSm T,the non-exclusiveness is expressed by propositions’intersection and the fusion of evidence is realized through a Proportional Conflict Redistribution(PCR)*** order to handle non-exclusive FODs,a new framework called D Number Theory(DNT)has been proposed recently,which quantifies the non-exclusive degree between propositions different from DSm *** previous studies,an Exclusive Conflict Redistribution(ECR)rule has been designed in DNT to implement the fusion of evidence defined on a non-exclusive FOD,but there are some deficiencies in the ECR *** this paper,a new rule called ECR-PCR rule is proposed by combining the ECR and PCR rules to better implement the fusion of evidence defined on a nonexclusive *** the proposed rule,the definition of conflict utilizes the idea of ECR’s exclusive conflict,and the disposal of conflict is following the idea of PCR’s proportional *** of the ECR-PCR rule are *** effectiveness of the proposed new rule is verified through numerical examples and applications,in comparison with other fusion methods.

关键词： D number theory Dempster-Shafer theory Evidence combination Non-exclusiveness Proportional Conflict Redistribution rule Information fusion

Neogene integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 310-323页

作者： Tao deng Sukuan HOU Shiqi WANG Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment Department of Earth Sciences University of Chinese Academy of Sciences Department of Earth Sciences Nanjing University

The widely exposed Chinese Neogene terrestrial deposits provide the best circumstance for the establishment of an accurate chronostratigraphic system of Eurasia, and the rapidly evolved mammalian fossils contribute efficiently to the division and correlation of Asian Neogene strata. A uniform Neogene biostratigraphic framework for China has already been established,with seven mammalian ages named. With a developed stratigraphic basis for the geochronologic "ages", seven chronostratigraphic "stage" have been established for the Chinese Neogene terrestrial strata, namely the Miocene Xiejian, Shanwangian,Tunggurian, Bahean, and Baodean stages, and the Pliocene Gaozhuangian and Mazegouan stages. Based on a series of research achievements, refined biostratigraphic, paleomagnetic and isotopic methods were combined and applied to continuous sections,and a Chinese Neogene chronostratigraphic sequence with accurate geological ages was established and improved in recent years. The lower boundaries of most of the stages could be correlated with those of the marine stages in the International Chronostratigraphic Chart, except the Tunggurian Stage, which is correlated with the European land mammal age. The biostratigraphic markers of the Chinese Neogene stages are usually first appearance of a single taxon, some representing regional species replacement, others indicating intercontinental migration of certain taxa. Candidate stratotype sections have been proposed for all the Chinese Neogene stages according to the principle and rule of modern stratigraphy, and other Chinese Neogene strata in different regions are comprehensively correlated.

关键词： Neogene Stage/age Mammal Biostratigraphy Chronostratigraphy Magnetostratigraphy China

Stability of stochastic neural networks with Markovian jumping parameters

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Journal of Systems Engineering and Electronics 2009年第3期20卷 613-618页

作者： Hua Mingang deng Feiqi Peng Yunjian Coll. of Automation Science and Engineering South China Univ. of Technology Guangzhou 510640 P. R. China

The global asymptotical stability for a class of stochastic delayed neural networks （SDNNs） with Maxkovian jumping parameters is considered. By applying Lyapunov functional method and Ito＇s differential rule, new delay-dependent stability conditions are derived. All results are expressed in terms of linear matrix inequality （LMI）, and a numerical example is presented to illustrate the correctness and less conservativeness of the proposed method.

关键词： stochastic neural networks global asymptotical stability linear matrix inequality Markovian jumping parameters.

Influence rule of downtime on heat transfer in converters

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Journal of Iron and Steel Research International 2019年第3期26卷 251-258页

作者： Shuai deng An-jun Xu Rui-yu Yin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The models for calculating the heat transfer in converters allow the accurate control of heat dissipation caused by downtime,and thus help in crease scrap ratio and reduce energy consumptio *** 17 was used to establish such a model to analyse the coupling law between the downtime and heat dissipation of the converter and the temperature drop of molten *** was measured by infrared detection,and model accuracy was verified by comparative *** variation law of the amount of cold charge added for different downtimes under different process conditions was *** results show that the range of the variation of heat dissipation caused by downtime is 8.9-78.5 *** the downtime increases by 30 min,heat dissipation of dephosphorisation(deP)and decarburisation(deC)converters increases by about 23.4 and 41.3 GJ,*** a certain smelting cycle,the temperature drop of the molten iron for deP,deC and conventional converters increases by about 12.5,15.0 and 17.0 K,respectively;and the amount of scrap added in the double-linking and conventional smelting processes decreases by 0.93 and 0.75%,respectively.

关键词： Downtime Converter heat dissipation Scrap ratio Temperature field Finite element

Decoupled Wiener state fuser for descriptor systems

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维普期刊数据库

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控制理论与应用（英文版） 2008年第4期6卷 365-371页

作者： Chenjian RAN Zili deng Department of Automation Heilongjiang University Harbin Heilongjiang 150080 China

By the modem time series analysis method, based on the autoregressive moving average （ARMA） innovation models and white noise estimation theory, using the optimal fusion rule weighted by diagonal matrices, a distributed descriptor Wiener state fuser is presented by weighting the local Wiener state estimators for the linear discrete stochastic descriptor systems with multisensor. It realizes a decoupled fusion estimation for state components. In order to compute the optimal weights, the formulas of computing the cross-covariances among local estimation errors are presented based on cross-covariances among the local innovation processes, input white noise, and measurement white noises. It can handle the fused filtering, smoothing, and prediction problems in a unified framework. Its accuracy is higher than that of each local estimator. A Monte Carlo simulation example shows its effectiveness and correctness.

关键词： Multisensor information fusion Weighted fusion Decoupled fusion Descriptor system Wiener statefuser White noise estimator ARMA innovation model Modern time series analysis method

SIGNGD with Error Feedback Meets Lazily Aggregated Technique:Communication-Efficient Algorithms for Distributed Learning

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Tsinghua Science and Technology 2022年第1期27卷 174-185页

作者： Xiaoge deng Tao Sun Feng Liu Dongsheng Li National Laboratory for Parallel and Distributed Processing(PDL) College of ComputerNational University of Defense TechnologyChangsha 410073China

The proliferation of massive datasets has led to significant interests in distributed algorithms for solving large-scale machine learning ***,the communication overhead is a major bottleneck that hampers the scalability of distributed machine learning *** this paper,we design two communication-efficient algorithms for distributed learning *** first one is named EF-SIGNGD,in which we use the 1-bit(sign-based) gradient quantization method to save the communication ***,the error feedback technique,i.e.,incorporating the error made by the compression operator into the next step,is employed for the convergence *** second algorithm is called LE-SIGNGD,in which we introduce a well-designed lazy gradient aggregation rule to EF-SIGNGD that can detect the gradients with small changes and reuse the outdated ***-SIGNGD saves communication costs both in transmitted bits and communication ***,we show that LE-SIGNGD is convergent under some mild *** effectiveness of the two proposed algorithms is demonstrated through experiments on both real and synthetic data.

关键词： distributed learning communication-efficient algorithm convergence analysis

基于规则引擎的煤矿透明地质物联网接入系统开发研究

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煤炭技术 2025年第1期44卷 234-237页

作者：邓良晏俊生李鹏中煤科工西安研究院(集团)有限公司西安710077 西安煤科透明地质科技有限公司西安712000 煤炭科学研究总院北京100013

随着我国煤矿智能化建设的快速推进,以及海量煤矿地质相关数据的不断积累,统一、安全、智能、高效的煤矿透明地质平台建设已经成为了重要研发方向。以物联网,时序存储,规则引擎等技术为基础,分析了海量多源异构煤矿透明地质数据的接入... 详细信息

随着我国煤矿智能化建设的快速推进,以及海量煤矿地质相关数据的不断积累,统一、安全、智能、高效的煤矿透明地质平台建设已经成为了重要研发方向。以物联网,时序存储,规则引擎等技术为基础,分析了海量多源异构煤矿透明地质数据的接入、管理、存储,研发了煤矿透明地质物联网接入系统。设计了异构传感器设备动态数据的协议接入、存储、管理及推送服务。系统的研发有效降低了多源异构协议数据的接入与管理成本,提高了煤矿系统实时数据的可用性、可扩展性、可访问性。在察哈素煤矿透明地质保障系统建设中,系统高效完善了系统动态数据接入、存储和分析,将系统数据接入成本从5人/月降低至0.5人/月,极大提升了系统运行效率,缩减了系统运维成本,达到预期建设效果。

关键词：物联网时序数据透明地质规则引擎多源异构数据