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Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems

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自动化学报：英文版 2023年第4期10卷 997-1008页

作者： Wenji cao Lu Liu Gang feng Department of Biomedical Engineering City University of Hong KongHong Kong SARChina

This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed graphs.The dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative degrees.This is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control law.It is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader asymptotically.The effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example.

关键词： Adaptive pole placement control heterogeneous multi-agent systems leader-following output consensus non-minimum phase

Biome reconstruction on the Tibetan Plateau since the Last Glacial Maximum using a machine learning method

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Science China Earth Sciences 2022年第3期65卷 518-535页

作者： feng QIN Yan ZHAO Xianyong cao Key Laboratory ofLand Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Alpine Paleoecology and Human Adaptation(ALPHA)Group State Key Laboratory of Tibetan Plateau Earth System Science(LATPES)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Historical biome changes on the Tibetan Plateau provide important information that improves our understanding of the alpine vegetation responses to climate changes.However,a comprehensively quantitative reconstruction of the historical Tibetan Plateau biomes is not possible due to the lack of quantitative methods that enable appropriate classification of alpine biomes based on proxy data such as fossil pollen records.In this study,a pollen-based biome classification model was developed by applying a random forest algorithm(a supervised machine learning method)based on modern pollen assemblages on and around the Tibetan Plateau,and its robustness was assessed by comparing its results with the predictions of the biomisation method.The results indicated that modern biome distributions reconstructed using the random forest model based on modern pollen data generally concurred with the observed zonal vegetation.The random forest model had a significantly higher accuracy than the biomisation method,indicating the former is a more suitable tool for reconstructing alpine biome changes on the Tibetan Plateau.The random forest model was then applied to reconstruct the Tibetan Plateau biome changes from 22 ka BP to the present based on 51 fossil pollen records.The reconstructed biome distribution changes on the Tibetan Plateau generally corresponded to global climate changes and Asian monsoon variations.In the Last Glacial Maximum,the Tibetan Plateau was mainly desert with subtropical forests distributed in the southeast.During the last deglaciation,the alpine steppe began expanding and gradually became zonal vegetation in the central and eastern regions.Alpine meadow occupied the eastern and southeastern areas of the Tibetan Plateau since the early Holocene,and the forest-meadow-steppe-desert pattern running southeast to northwest on the Tibetan Plateau was established afterwards.In the mid-Holocene,subtropical forests extended north,which reflected the“optimum”condition.During the late Holocene,alpine meadows and alpine s

关键词： Biome reconstruction Random forest algorithm Biomisation method Pollen data Last Glacial Maximum Tibetan Plateau

Effects of sodium-glucose cotransporter 2 inhibitors on cardiovascular outcomes in elderly patients with comorbid coronary heart disease and diabetes mellitus

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Journal of Geriatric Cardiology 2021年第6期18卷 440-448页

作者： Hu XU Wen-Zhe cao Yong-Yi BAI Rui-Hua cao Lei TIAN Feng Cao Li FAN Chinese PLA Medical School Chinese PLA General HospitalBeijingChina Department of Cardiology the Second Medical CenterNational Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijingChina Institute of Geriatrics the Second Medical CenterChinese PLA General HospitalBeijingChina

OBJECTIVE To investigate the effects of sodium-glucose cotransporter 2 inhibitors(SGLT2i)on cardiovascular outcomes in elderly Chinese patients with comorbid coronary heart disease(CHD)and type 2 diabetes mellitus(T2DM).METHODS A retrospective cohort study was conducted on 501 elderly inpatients(≥60 years)with comorbid CHD/T2DM in Department of Cardiovascular Medicine and Endocrinology,Chinese PLA General Hospital from January 2018 to December 2019.These patients were divided into two groups according to the administration of SGLT2i.All the demographic characteristics and clinical data were collected.Cardiovascular outcomes,including all-cause mortality,major adverse cardiovascular events(MACE),and hospitalization for heart failure(HHF),were followed up.RESULTS In the cohort,there were 167 patients in the SGLT2i group and 334 patients in the control group.In the efficacy analyses,the incidence of MACE was lower in the SGLT2i group than in the control group:3.6%vs.9.3%(P=0.022).A lower risk of MACE was observed in the SGLT2i group[hazard ratio(HR)=0.40,95%CI:0.17-0.95].There was no significant difference in the incidence of all-cause mortality or HHF between the two groups.No significant difference of HR was observed for all-cause mortality(HR=0.41,95%CI:0.12-1.41)or HHF(HR=0.58,95%CI:0.12-2.81).CONCLUSIONS SGLT2i treatment exhibited benefits for elderly patients with comorbid CHD/T2DM with a lower risk for MACE.

关键词： patients morbid mortality

N-doped carbon nanofibers arrays as advanced electrodes for supercapacitors

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Journal of Materials Science & Technology 2020年第20期52卷 144-151页

作者： Guoxiang Pan Feng Cao Yujian Zhang Xinhui Xia Department of Materials Chemistry Huzhou UniversityHuzhou 313000China State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Provinceand Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The advancement of supe rcapacitors largely relies on the innovation of electrode materials with high-rate performance and ultra-long cycling stability.In this work,unique N-doped nanofibers on carbon cloth(NCNFs/CC) are prepared by an electrodepositio n-annealing method for application in supercapacitors.The as-prepared N-doped nanofibers(N-CNFs) show diameters of 100-150 nm and cross-link with each other fo rming porous conductive network.Due to enhanced conductivity and reinforced structural stability,the N-CNFs/CC arrays are demonstrated with better electrochemical performance than CNFs/CC counterpart,including higher specific capacitance(195.2 F g^-1 at a current density of 2.5 A g^-1),excellent rate capability(80.5.% capacity retention as the rate increases from 2.5-20 A g^-1) and good cycling stability(99.5.%retention after 10,000 cycles).These reinforced electrochemical properties are attributed to N-doped conductive architecture with faster ion/electron transfer paths and more active sites.Our findings may offe r a new way for construction of advanced high-rate electrodes for energy storage.

关键词： Supercapacitors Carbon fibers Electrode Porous materials Electrodeposition

Analysis for Multiple Cracks in 2D Piezoelectric Bimaterial Using the Singular Integral Equation Method

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Acta Mechanica Solida Sinica 2022年第2期35卷 261-272页

作者： Ting cao Xiaobin feng Taiyan Qin College of Engineering China Agricultural UniversityBeijing 100083China Department of CAE BYD Auto Industry Co.LtdShenzhen 518118China College of Science China Agricultural UniversityBeijing 100083China

A singular integral equation method is proposed to analyze the two-dimensional(2D)multiple cracks in anisotropic piezoelectric bimaterial.Using the Somigliana formula,a set of singular integral equations for the multiple crack problems are derived,in which the unknown functions are the derivatives of the generalized displacement discontinuities of the crack surfaces.Then,the exact analytical solution of the extended singular stresses and extended stress intensity factors near the crack tip is obtained.Singular integrals of the singular integral equations are computed by the Gauss-Chebyshev collocation method.Finally,numerical solutions of the extended stress intensity factors of some examples are presented and discussed.

关键词： Piezoelectric bimaterial Boundary element method(BEM) Singular integral equation Stress intensity factor(SIF)

Estimation of Hammerstein nonlinear systems with noises using filtering and recursive approaches for industrial control

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 260-271页

作者： Mingguang ZHANG feng LI Yang YU QingFeng Cao School of Electrical&Information Engineering Jiangsu University of TechnologyChangzhou213001China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225127China

This paper discusses a strategy for estimating Hammerstein nonlinear systems in the presence of measurement noises for industrial control by applying filtering and recursive approaches.The proposed Hammerstein nonlinear systems are made up of a neural fuzzy network(NFN)and a linear state`-space model.The estimation of parameters for Hammerstein systems can be achieved by employing hybrid signals,which consist of step signals and random signals.First,based on the characteristic that step signals do not excite static nonlinear systems,that is,the intermediate variable of the Hammerstein system is a step signal with different amplitudes from the input,the unknown intermediate variables can be replaced by inputs,solving the problem of unmeasurable intermediate variable information.In the presence of step signals,the parameters of the state-space model are estimated using the recursive extended least squares(RELS)algorithm.Moreover,to effectively deal with the interference of measurement noises,a data filtering technique is introduced,and the filtering-based RELS is formulated for estimating the NFN by employing random signals.Finally,according to the structure of the Hammerstein system,the control system is designed by eliminating the nonlinear block so that the generated system is approximately equivalent to a linear system,and it can then be easily controlled by applying a linear controller.The effectiveness and feasibility of the developed identification and control strategy are demonstrated using two industrial simulation cases.

关键词： Hammerstein nonlinear systems Neural fuzzy network Data filtering Hybrid signals Industrial control

The Brain Connectome for Chinese Reading

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Neuroscience Bulletin 2022年第9期38卷 1097-1113页

作者： Wanwan Guo Shujie Geng Miao cao Jianfeng feng Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghai200433China Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Ministry of Education) Fudan UniversityShanghai200433China

Chinese,as a logographic language,fundamentally differs from alphabetic languages like English.Previous neuroimaging studies have mainly focused on alphabetic languages,while the exploration of Chinese reading is still an emerging and fast-growing research field.Recently,a growing number of neuroimaging studies have explored the neural circuit of Chinese reading.Here,we summarize previous research on Chinese reading from a connectomic perspective.Converging evidence indicates that the left middle frontal gyrus is a specialized hub region that connects the ventral with dorsal pathways for Chinese reading.Notably,the orthography-to-phonology and orthography-to-semantics mapping,mainly processed in the ventral pathway,are more specific during Chinese reading.Besides,in addition to the left-lateralized language-related regions,reading pathways in the right hemisphere also play an important role in Chinese reading.Throughout,we comprehensively review prior findings and emphasize several challenging issues to be explored in future work.

关键词： Brain connectome Chinese reading Word recognition Reading comprehension Structural connectivity Functional connectivity

Do supply shocks in the audit partner labor market affect auditor choice?Evidence from a quasi-natural experiment

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China Journal of Accounting Research 2022年第1期15卷 5-25页

作者： Yanming cao Zhuoan feng Department of Accounting and Corporate Governance Macquarie UniversityNorth RydeNSWAustralia School of Accounting Finance and EconomicsUniversity of WaikatoHamiltonWaikatoNew Zealand

We examine whether supply shocks in the audit partner labor market induce clients to switch audit partners.We argue that audit partners in their early careers(i.e.,junior partners)charge low audit fees to attract clients,which induces client firms to switch from senior partners to junior partners when there are more junior partners available.Utilizing the Big4 localization policy,we find that Big4 clients are more likely to replace senior auditors with junior auditors to cut costs after the policy.Furthermore,the results are mainly driven by clients who are charged high fees.Our empirical evidence enriches the understanding of auditor choice determinants and informs the ongoing debates surrounding new regulations for Big4 firms in China.

关键词： Audit partner labor market Audit fees Auditor switch Big4 auditors Supply shock of audit labor market

Progress in prevention and treatment of myocardial injury induced by cancer therapy

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Chinese Medical Journal 2019年第22期132卷 2724-2728页

作者： Jia-Xin Miao Shan Gao Li Fan Feng Cao Department of Cardiology Chinese People's Liberation Army General HospitalBeijing 100853China National Clinical Research Center for Geriatrics Disease Beijing 100853China Beijing Key Laboratory of Chronic Heart Failure Precision Medicine Beijing 100853China

Objective:This article aims to present a brief profile of the advances in prevention and treatment of myocardial injury in therapy based on relevant literature or reports.Data sources:The data cited in this review were obtained from articles indexed in PubMed and China National Knowledge Internet(CNKI)up to June 2019.Study selection:Articles were selected with the following keywords "Anti-cancer therapy,M""Myocardial injury,""Breast cancer,5,44Echocardiography," and "Chemotherapy." Results:Due to the rapid development of novel cancer therapeutic approaches,the life expectancy of tumor patients has been prolonged continuously.Meanwhile,a large number of studies have found that among patients benefiting from precise management,some medications have exerted direct or indirect side effects on the cardiovascular system,leading to the occurrence of myocardial injury.Because there are many common risk factors between breast cancer and cardiovascular disease,and there is a special anatomical position between breast and heart,the cardiology related to breast cancer patients is relatively unique in onco-cardiology.Conclusions:Heart function monitoring is critical during anti-cancer therapy so that we can early identify cardiac abnormalities and actively adopt measures to prevent myocardial injury.

关键词： Myocardial injury Anti-cancer therapy Tumor