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UAV swarm formation reconfiguration control based on variable-stepsize MPC-APCMPIO algorithm

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Science China(Information Sciences) 2023年第11期66卷 222-243页

作者： Jian LIAO Jun CHENG Bin XIN Delin LUO lihui zheng Yuhang KANG Shaolei ZHOU School of Physics and Electronic Information Gannan Normal University Shenzhen Institute of Advanced Technology Chinese Academy of Sciences School of Automation Beijing Institute of Technology School of Aerospace Engineering Xiamen University School of Electronic Information Northwest University of Technology 6. School of Basic Science Naval Aviation University of PLA

For a complex operational environment, to actualize safe obstacle avoidance and collision avoidance, a swarm must be capable of autonomous formation reconfiguration. First, this paper introduces the basic pigeon-inspired optimization(PIO) algorithm, and establishes the unmanned aerial vehicle motion model and the virtual leader swarm formation control structure. Then, given the above knowledge, the basic error objective function of a UAV swarm, obstacle avoidance objective function, and collision avoidance objective function are devised based on the variable-stepsize model predictive control technique. Next,the adaptive perception Cauchy mutation PIO algorithm is proposed by introducing the Cauchy mutation operator, adaptive weight factor, and roulette wheel selection into the basic PIO. This algorithm is used to optimally solve the abovementioned swarm objective functions. Ultimately, a set of comparative simulations are performed to verify the effectiveness and reliability of the proposed algorithm.

关键词： unmanned aerial vehicle swarm formation reconfiguration variable-stepsize model predictive control (MPC) adaptive perception Cauchy mutation pigeon-inspired optimization (APCMPIO) obstacle avoidance

The mechanism for fuzzy-ball working fluids for controlling & killing lost circulation

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Chinese Science Bulletin 2010年第35期55卷 4074-4082页

作者： zheng lihui KONG LingChen CAO Yuan WANG HuiYun HE XiaoQing MOE Key Laboratory of Petroleum Engineering China University of Pet'roleum Beijing 102249 China

Lost circulation controlling & killing material has been a focused issue since a long time ago.A novel leak resistance fluid with the raw materials such as SDS,SDBS,HES,PAM and proprietary productions has been developed from *** experiment and application shows that the new leak resistance fluid can plug leaking passage of different sizes *** with 1000 to 2000 time microscope,it is found that the working liquid contains a kind of spherical material which has the microstructure of "one core,two layers,and three membranes".When it is in a static state,the inside of the material looks like an airbag and the outside looks like some fuzzy things which has high gel *** when it is in a dynamic state,the fuzzy thing is cut or scattered and flow ability becomes much *** is the reason why it is called *** the diameter or the width of the leak passage is greater than the fuzzy-ball's,the fuzzy-ball accumulates in conical shape to decompose the working fluid pressure of liquid column to achieve blocking;when the diameter or the width of the leak passage is equivalent to the fuzzy-ball's,the fuzzy-ball changes from sphere to oval-shape to increase the resistance to the leak passage and plug the holes;when the diameter or the width of the leak passage is smaller than the fuzzy-ball's,the leaks could be blocked up by the non-permeable membrane formed by the gel of high strength in the working *** these cases,the leak passages of different sizes could be blocked comprehensively.

关键词：模糊工作流体十二烷基苯磺酸钠泄漏通道十二烷基硫酸钠通道宽度机制制球

The associations between multiple circulating biomarkers and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy with or without left ventricular outflow tract obstruction

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中国循环杂志 2018年第S1期33卷 155-156页

作者： Limin Liu Lingmin Wu lihui zheng Ligang Ding Gang Chen Xiaohan Fan Yan Yao National Center for Cardiovascular Diseases Fuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Objective Atrial fibrillation(AF)is the most common arrhythmia that can portend adverse prognosis in patients with hypertrophic cardiomyopathy(HCM).Data regarding the correlations of different biomarkers and AF in HCM patients are rather *** this study,we sought to explore the associations between the occurrence of AF and circulating biomarkers reflecting cardiovascular function(N-terminal pro-Brain natriuretic peptide,NT-proBNP),endothelial function(big endothenlin-1,big ET-1),inflammation(high-sensitivity C-reactive protein,hs-CRP)and myocardial damage(cardiac troponin I,cTnI)in HCM patients with or without left ventricular outflow tract obstruction(LVOTO),respectively.

关键词： Atrial fibrillation HCM NT-proBNP

Portfolio Construction for Value Appreciation

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Journal of Applied Mathematics and Physics 2016年第4期4卷 662-668页

作者： Michael Ha George Z. Liu lihui zheng Financial Mathematics Programme Xi’an Jiaotong-Liverpool University Suzhou China Risk Strategy & Derivatives Asia Pacific Allianz Global Investors Hong Kong China Risk Management Department Huatai-Pinebridge Fund Management Co. Ltd. Shanghai China

Background: While working as risk consultants at Barra in 1990’s, the first two authors decided to start collaborating on a research project with its first paper titled “Application of Volatility in Portfolio Construction” [1]. The third author was then a risk manager of a financial institution which was a client of Barra’s. Bringing his expertise in portfolio risk management, he joined the research team. Aim: The core of this paper lies in the construction of an investment portfolio with a main objective of value appreciation while examining its tracking error [1]-[3], a risk measurement with reference to a benchmark [1] [4]. The authors believe, while tracking error measurement is a common tool for portfolio risk management, total risk measurement is more important. The management goal is to minimize drawbacks using the technique of risk budgeting. These topics will be discussed in future research papers.

关键词： Tracking Error Beta Valuation Exposure Monitoring Rebalance

Application of Volatility in Portfolio Construction

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Journal of Applied Mathematics and Physics 2015年第7期3卷 808-813页

作者： Michael Ha George Z. Liu lihui zheng Department of Mathematical Sciences Xi’an Jiaotong-Liverpool University Suzhou China Head of Risk Strategy & Derivatives Asia Pacific Allianz Global Investors Hong Kong China Head of Risk Management Department Huatai-Pinebridge Fund Management Co. Ltd Shanghai China

We studied the CBOE Market Volatility Index from 1995 to 2004 and the Cross-Sectional Volatility of MSCI US and MSCI AC Asia ex Japan of the same period. Tracking Error calculations and Market Volatility Analyses were performed. We selected a portfolio, Dragon, for Risk Analysis, Risk Decomposition and Risk Characteristics identification purposes. A conclusion relating Dragon’s Tracking Error and its Portfolio Size was drawn.

关键词： Volatility VIX Tracking Error Active Risk Risk Decomposition Risk Characteristics

流动注射-阴离子树脂富集光度法测定环境水中痕量钍

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工业水处理 2010年第10期30卷 78-80页

作者：罗道成郑李辉湖南科技大学化学化工学院湖南湘潭411201

研究了采用流动注射技术结合阴离子树脂分离富集痕量钍。在0.30mol/L的HCl介质中,Th(Ⅳ)与Cl-形成络阴离子,被阴离子树脂分离富集,用0.25mol/LHNO3-质量分数2.5%柠檬酸溶液洗脱富集在阴离子树脂上的Th(Ⅳ),Th(Ⅳ)能与偶氮氟胂-Ⅲ(FAsA-... 详细信息

研究了采用流动注射技术结合阴离子树脂分离富集痕量钍。在0.30mol/L的HCl介质中,Th(Ⅳ)与Cl-形成络阴离子,被阴离子树脂分离富集,用0.25mol/LHNO3-质量分数2.5%柠檬酸溶液洗脱富集在阴离子树脂上的Th(Ⅳ),Th(Ⅳ)能与偶氮氟胂-Ⅲ(FAsA-Ⅲ)发生显色反应,据此建立了测定痕量钍(Ⅵ)的流动注射-光度法的新方法。结果表明,在实验条件下,FAsA-Ⅲ与Th(Ⅳ)反应生成稳定的络合物,其最大吸收波长为656nm,钍的质量浓度在0～800μg/L内符合比耳定律,方法的检出限为1.0μg/L。经分离富集后对钍的测定灵敏度可提高数倍,大量共存离子不干扰钍的测定。该法已应用于环境水中痕量钍的测定,结果令人满意。

关键词：流动注射光度法偶氮氟胂-Ⅲ 钍富集

电动拖拉机电驱系统故障预测模型——基于深度学习

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农机化研究 2024年第10期46卷 254-258页

作者：郑丽辉衢州职业技术学院浙江衢州324000

电动拖拉机作为一种新型农业机械之一,具有环保、节能、高效和控制灵活等应用优势,适用于温室大棚和生态农业环境,且其机电驱动系统是保证拖拉机运行可靠性和田间工作质量的重要条件。探究一种高效且精确的电驱动系统故障预测模型与识... 详细信息

电动拖拉机作为一种新型农业机械之一,具有环保、节能、高效和控制灵活等应用优势,适用于温室大棚和生态农业环境,且其机电驱动系统是保证拖拉机运行可靠性和田间工作质量的重要条件。探究一种高效且精确的电驱动系统故障预测模型与识别方法,对于保证电动拖拉机运行稳定性具有重要意义。针对以上问题,建立了电动拖拉机振动信号采集装置,基于经验模态分解出各个关键部件振动信号潜在故障分量,并将其作为神经网络输入变量进行模型训练,从而建立基于人工神经网络模型的电动拖拉机电驱系统故障故障预测模型。研究结果表明:预测精准度较高,可以满足实际生产需求。

关键词：电动拖拉机电驱动总成模态分解故障预测模型

心脏神经消融术治疗功能性窦房结功能障碍的研究进展

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中国循环杂志 2024年第11期39卷 1140-1144页

作者：陈爱月郑黎晖中国医学科学院、北京协和医学院、国家心血管病中心、阜外医院心律失常中心北京100037

对于功能性窦房结功能障碍(SND)患者,心脏自主神经系统(ANS)的调节失衡可能是其发病机制。心脏神经消融术(CNA)作为一种新疗法,通过消融心脏自主神经节可提升功能性心动过缓患者的心率、改善患者症状。本文从患者选择、ANS、消融技术及... 详细信息

对于功能性窦房结功能障碍(SND)患者,心脏自主神经系统(ANS)的调节失衡可能是其发病机制。心脏神经消融术(CNA)作为一种新疗法,通过消融心脏自主神经节可提升功能性心动过缓患者的心率、改善患者症状。本文从患者选择、ANS、消融技术及临床疗效及安全性四个方面总结了近年来国内外应用CNA治疗功能性SND患者的研究。CNA可能作为SND患者起搏器植入的潜在替代方案,但仍需要具备更大样本量及更长随访时间的研究来进一步证实。

关键词：心动过缓窦房结功能障碍窦性心动过缓心脏自主神经系统心脏神经消融术

仿生绒囊钻井液煤层气钻井应用现状与发展前景

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石油钻采工艺 2011年第3期33卷 78-81,90页

作者：郑力会中国石油大学石油工程教育部重点实验室北京102249

仿照细菌结构开发了含仿生绒囊的钻井液。CLY-A井欠平衡钻井表明,无需附加设备,调整钻井液密度0.8～1.0g/cm3即可循环;CLY-B井空气钻井表明,空气钻井过程中添加不同绒囊处理剂,可实现空气、雾、泡沫和绒囊不停钻转换钻井工作流体;DFS-C... 详细信息

仿照细菌结构开发了含仿生绒囊的钻井液。CLY-A井欠平衡钻井表明,无需附加设备,调整钻井液密度0.8～1.0g/cm3即可循环;CLY-B井空气钻井表明,空气钻井过程中添加不同绒囊处理剂,可实现空气、雾、泡沫和绒囊不停钻转换钻井工作流体;DFS-C井防漏堵漏钻井表明,分压、耗压、撑压方式可控制钻井液漏失速度;FL-D分支井钻井表明,该钻井液具有低剪切速率下高黏度和高剪切速率下低黏度的特性,能够提高井眼清洁效率和机械钻速;J-E井不同压力系统共存于同一裸眼的井下复杂处理表明,该钻井液可以提高低压井段承压能力,满足动态窄密度窗口地层安全钻井。绒囊钻井液应加强绒囊结构微观研究、绒囊钻井液类型开发和低密度循环极限评价等,满足更多地层条件钻井需要。

关键词：绒囊钻井液煤层气钻井应用