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Neural Network Based Adaptive Tracking of Nonlinear Multi-Agent System

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Journal of Electronic Science and Technology 2021年第2期19卷 144-154页

作者： bo-xian Lin Wei-Hao Li Kai-Yu Qin xi Chen School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731

In this paper,the problems of robust consensus tracking control for the second-order multi-agent system with uncertain model parameters and nonlinear disturbances are *** adaptive control strategy is proposed to smooth the agent’s trajectory,and the neural network is constructed to estimate the system’s unknown *** consensus conditions are demonstrated for tracking a leader with nonlinear dynamics under an adaptive control algorithm in the absence of model ***,the results are extended to the system with unknown time-varying disturbances by applying the neural network estimation to compensating for the uncertain parts of the agents’*** laws are designed based on the Lyapunov function terms to ensure the effectiveness of robust ***,the theoretical results are verified by numerical simulations,and a comparative experiment is conducted,showing that the trajectories generated by the proposed method exhibit less oscillation and converge faster.

关键词： Coordinated tracking leader following consensus neural network based adaptive control robust control uncertain nonlinear system

Machine learning accelerated DFT research on platinum-modified amorphous alloy surface catalysts

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Chinese Chemical Letters 2023年第5期34卷 645-649页

作者： xi Zhang Kangpu Li bo Wen Jiang Ma Dongfeng Diao Institute of Nanosurface Science and Engineering Guangdong Provincial Key Laboratory of Micro/NanoShenzhen UniversityShenzhen 518060China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Research Center of Medical Plasma Technology Shenzhen UniversityShenzhen 518060China

Pt-modified amorphous alloy(Pt@PdNiCuP)catalyst exhibits excellent electro-catalytic activity and high experimental durability for hydrogen evolution reaction(HER).However,the physical origin of the catalytically active remains *** this paper,we constructed a distance contribution descriptor(DCD)for the feature engineering of machine learning(ML)potential,and calculated the Gibbs free energies(ΔGH)of 46,000*H binding sites on the Pt@Pd Ni Cu P surface by ML-accelerated density functional theory(DFT).The relationship betweenΔGHand DCD revealed that in the H-Pt distance region of 2.0-2.5 A where the parabolic tail and disordered scatters coexist,the H-metal bonding configuration is mainly the bridge-or hollow-bonding *** contribution analysis of DCD indicates that the joint effect of Pt,Pd and Ni atoms determines the catalytical behavior of amorphous alloy,which agrees well with experimental *** counting atomic percentages in different energy intervals,we obtained the atomic ratio for the best catalytic performance(Pt:Pd:Ni:Cu:P=0.33:0.17:0.155:0.16:0.185).Projected density of states(PDOS)show that H 1s orbital,Pt 5d orbital,and Pd 4d orbital form a bonding state at-2 e *** results provide new ideas for designing more active amorphous alloy catalysts.

关键词： Hydrogen evolution reaction Amorphous alloy Density functional theory Machine learning

A new scoring system for assessment of liver function after successful hepatectomy in patients with hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 265-269页

作者： Zheng-Gui Du,bo Li,Yong-Gang Wei,Jie yin,xi Feng and xi Chen Department of Liver and Vascular Surgery,West China Hospital,Sichuan University,Chengdu 610041,China Department of Liver and Vascular Surgery West China Hospital Sichuan University Chengdu 610041 China

BACKGROUND:Whether a major liver resection is safe has been judged mainly from the patient’s hepatic ***,a safe limit for liver resection does not exist *** study aimed to construct a new scoring system as a guide to determine a safe limit for liver resection and avoid liver dysfunction after ***:Eighty-six patients with hepatocellular carcinoma who had undergone hepatectomy in West China Hospital from March 2007 to June 2010 were *** patients were classified according to the levels of total bilirubin after hepatectomy and the parameters in the perioperative period were *** operating characteristic (ROC) analysis was made to assess the liver function compensatory (LFC) value to predict liver dysfunction of the patients after *** value is defined as the preoperative KICG value×22.487+standard remnant liver volume (SRLV)×***:Patients were classified into group Ⅰ (normal group,n=69) and group Ⅱ (with total bilirubin >85.5 μmol/L for 7 days after hepatectomy,n=17) based on the levels of total bilirubin after *** II was further divided into two subgroups:recovered subgroup (n=14) and fatal subgroup (n=3).There were no significant differences in preoperative data or intraoperative findings except the indocyanine green test parameters (KICG and ICG R15) and *** analysis showed that the sensitivity and specificity of an LFC value ≤13.01 were 94.1% and 82.6% respectively for predicting liver dysfunction of the patients after ***:The LFC value appears to be a good predictor of postoperative liver dysfunction in patients who undergo hepatectomy for *** expected LFC value of 13.01 seems to be a safe limit for liver resection.

关键词： indocyanine green test standard remnant liver volume hepatectomy liver dysfunction liver function reserve

Prevalence of hypertension and its associations with body composition across Chinese and American children and adolescents

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World Journal of Pediatrics 2024年第4期20卷 392-403页

作者： Li-Wang Gao Yi-Wen Huang Hong Cheng xi Wang Hong-bo Dong Pei xiao yin-Kun Yan xin-ying Shan xiao-Yuan Zhao Jie Mi Center for Non-Communicable Disease Management Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthNo.56 Nanlishi RoadXicheng DistrictBeijing100045China Department of Epidemiology Capital Institute of PediatricsNo.2 Yabao RoadChaoyang DistrictBeijing100020China Key Laboratory of Major Diseases in Children Ministry of EducationBeijingChina

Background The age of onset of hypertension(HTN)is decreasing,and obesity is a significant risk *** prevalence and racial disparities in pediatric HTN and the association between body composition and blood pressure are insufficiently *** study aimed to evaluate the prevalence of HTN in Chinese and American children and adolescents and to assess the relationship between various body composition indices and *** Seven thousand,five hundred and seventy-three Chinese and 6239 American children and adolescents aged 8–18 years from the 2013–2015 China Child and Adolescent Cardiovascular Health study and the 2011–2018 National Health and Nutrition Examination Surveys were *** pressure and body composition(fat and muscle)were measured by trained *** crude prevalence and age-standardized prevalence rate(ASPR)of primary HTN and its subtypes[isolated systolic hypertension(ISH)and isolated diastolic hypertension(IDH)]were calculated based on 2017 American Academy of Pediatrics ***-adjusted linear regression coefficients and odds ratios(ORs)were calculated to assess the associations of body composition indicators with HTN,ISH and *** The ASPR of HTN was 18.5%in China(CN)and 4.6%in the United States(US),whereas the obesity prevalence was 7.4%and 18.6%,and the population attributable risk of HTN caused by overweight and obesity was higher in the US than in *** fat mass,muscle mass and body fat percentage mass were associated with a higher risk of HTN in both *** percent of muscle body mass had a protective effect on HTN and ISH in both countries[HTN(CN:OR=0.83,95%CI=0.78–0.88;US:OR=0.72,95%CI=0.64–0.81);ISH(CN:OR=0.87,95%CI=0.80–0.94;US:OR=0.71,95%CI=0.62–0.81)],and the protective effect was more common among children and adolescents with high levels of physical *** The burden of HTN in Chinese children and adolescents was substantial and much greater than that in the US,and th

关键词： body composition Children and adolescents China Child and Adolescent Cardiovascular Health Hypertension National Health and Nutrition Examination Surveys

A visual awareness pathway in cognitive model ABGP

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High Technology Letters 2016年第4期22卷 395-403页

作者：马刚 Yang xi Lu Chengxiang Zhang bo Shi Zhongzhi The Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 P. R. China University of Chinese Academy of Sciences Beijing 100190 P. R. China

The cognitive model ABGP is a special model for agents,which consists of awareness,beliefs,goals and plans. The ABGP agents obtain the knowledge directly from the natural scenes only through some single preestablished rules like most agent architectures. Inspired by the biological visual cortex( V1) and the higher brain areas perceiving the visual feature,deep convolution neural networks( CNN) are introduced as a visual pathway into ABGP to build a novel visual awareness module. Then a rat-robot maze search simulation platform is constructed to validate that CNN can be used for the awareness module of ABGP. According to the simulation results,the rat-robot implemented by the ABGP with the CNN awareness module reaches the excellent performance of recognizing guideposts,which directly enhances the capability of the communication between the agent and the natural scenes and improves the ability to recognize the real world,which successfully demonstrates that an agent can independently plan its path in terms of the natural scenes.

关键词： ABGP visual cortex(V1) convolution neural networks(CNN) awareness visual pathway

Effect of rich air/fuel ratio and temperature on NO_x desorption of lean NO_x trap

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第11期14卷 835-842页

作者： Lei LIU Zhi-jun LI Hong-yang ZHANG Qing CHANG bo-xi SHEN State Key Laboratory of Engines Tianjin University

An experimental and model-based study of the effect of rich air/fuel ratios(AFRs) and temperature on the NOx slip of a lean NOx trap(LNT) was conducted in a lean-burn gasoline engine with an LNT after-treatment system. The emissions of the engine test bench and the inlet temperature of the LNT were used as the major inlet boundary conditions of the LNT. The engine periodically operated between a constant lean AFR of 23 with alterable rich AFRs of 10, 11, 12, 13, and 14. A decrease in the rich AFR of the engine strengthened the desorption atmosphere in the LNT, an effect closely related to the number of reductants, and further heightened the NOx desorption of the LNT, but with a penalty in fuel consumption. To eliminate that penalty, the inlet boundary conditions of the LNT were varied by adjusting the inlet temperature within a range between 200℃ and 400℃. An increase in inlet temperature heightened the NOx desorption of the LNT, and a NOx breakthrough occurred after the inlet temperature exceeded 390℃. To control NOx breakthrough, the inlet temperature can be adjusted to offset the strong desorption atmosphere in the LNT commonly created by a rich AFR.

关键词： Lean NOx trap (LNT) Air/fuel ratio (AFR) Temperature NOx adsorption NOx desorption

On Coupled KdV Equations with Self-consistent Sources

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Communications in Theoretical Physics 2008年第5期49卷 1091-1100页

作者： HUANG Ye-Hui WU Hong-xia xiE xi ZENG Yun-bo Department of Mathematical Sciences Tsinghua University Beijing 100084 China Department of Mathematics School of Science Jimei University Xiamen 361021 China

The coupled Korteweg-de Vries （CKdV） equation with self-consistent sources （CKdVESCS） and its Lax representation are derived. We present a generalized binary Darboux transformation （GBDT） with an arbitrary time- dependent function for the CKdVESCS as well as the formula for the N-times repeated GBDT. This GBDT provides non-auto-Biicklund transformation between two CKdVESCSs with different degrees of sources and enables us to construct more generM solutions with N arbitrary t-dependent functions. We obtain positon, negaton, complexiton, and negaton- positon solutions of the CKdVESCS.

关键词： coupled KdV equation with self-consistent sources generalized binary Darboux transformation positon negaton complexiton

A Chaotic Neural Network Model

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Chinese Physics Letters 1996年第3期13卷 185-188页

作者： SHUAI Jian-wei CHEN Zhen-xiang LIU Rui-tang WU bo-xi Department of Physics Xiamen UniversityXiamen 361005

A chaotic neural network model is introduced in this *** the variation of a controlling parameter,the model can process the input by a content-addressable means or fall into a chaotic *** the features of brain such as... 详细信息

关键词： state. chaotic letter

Total ionizing dose effects and annealing behaviors of HfO2-based MOS capacitor

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Science China(Information Sciences) 2017年第12期60卷 111-113页

作者： Yannan XU Jinshun BI Gaobo XU Kai xi bo LI Ming LIU Institute of Microelectronics Chinese Academy of Sciences University of Chinese Academy of Sciences

With the continuously scaling down of semiconductor technology,the traditional SiOas gate dielectric is approaching the physical and electrical *** problems,such as the increasing leakage current and reliability issues,seriously affect the transistor performance[1].HfOhas been considered to be one of the reasonable alternative solutions due to a suitable dielectric constant(about 25),the relatively large band gap(5.68 e V)

关键词： Figure Co MOS Si