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一种基于DTW-DP-GMM的工业机器人轨迹学习策略

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天津大学学报（自然科学与工程技术版） 2025年第1期58卷 68-80页

作者：肖洒陈旭阳叶锦华吴海彬福州大学机械工程及自动化学院福州350108 福建省特种智能装备安全与测控重点实验室福州350108

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法... 详细信息

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法.首先,针对示教过程中采集的多条轨迹在时间长度上存在差异的问题,采用DTW算法来统一示教轨迹在时域上的变化.其次,使用GMM算法对示教轨迹的特征进行提取,并利用高斯混合回归(GMR)算法将其重构为复现轨迹.在这个过程中采用DP算法来预估GMM算法的关键参数高斯分布的数量,与传统方法相比,能够简单直观地得到相对准确的参数值.利用DP算法对复现轨迹的数据点进行稀疏化并优化,不仅确保了机器人最终运动轨迹的精度,而且大幅减少了最终轨迹数据点的数量.最后,进行了不同形状的模拟焊接轨迹学习规划实验.结果表明:经由DTW对齐后的示教轨迹具有更加明显的运动特征,经过GMM-GMR学习输出的复现轨迹具有良好的表征结果;在使用GMM-GMR算法学习示教轨迹的过程中,采用DP算法可以有效预估高斯分布个数;经过DP算法稀疏化并优化的最终轨迹的平均位置误差均在0.500 mm以内,其最大误差可以控制在0.800 mm以内,可以满足焊接轨迹规划的精度要求,验证了该策略的有效性和优越性.

关键词：工业机器人示教编程高斯混合模型道格拉斯-普克算法动态时间规整轨迹复现

Effective regeneration of high-performance anode material recycled from the whole electrodes in spent lithium-ion batteries via a simplified approach

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Green Energy & Environment 2021年第5期6卷 725-733页

作者： Long ye Chunhui wang Liang Cao Hougui xiao Jiafeng Zhang Bao Zhang Xing Ou National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals School of Metallurgy and EnvironmentCentral South UniversityChangsha410083China

Along with the extensive application of energy storage devices,the spent lithium-ion batteries(LIBs)are unquestionably classified into the secondary resources due to its high content of several valuable ***,current recycling methods have the main drawback to their tedious process,especially the purification and separation ***,we propose a simplified process to recycle both cathode(LiCoO_(2))and anode(graphite)in the spent LIBs and regenerate newly high-performance anode material,CoO/CoFe2O4/expanded graphite(EG).This process not only has the advantages of succinct procedure and easy control of reaction conditions,but also effectively separates and recycles lithium from transition *** 98.43%of lithium is recovered from leachate when the solid product CoO/CoFe2O4/EG is synthesized as anode material for *** the product exhibits improved cyclic stability(890 mAh g^(-1) at 1 A g^(-1) after 700 cycles)and superior rate capability(208 mAh g^(-1) at 5 A g^(-1)).The merit of this delicate recycling design can be summarized as three aspects:the utilization of Fe impurity in waste LiCoO_(2),the transformation of waste graphite to EG,and the regeneration of anode *** approach properly recycles the valuable components of spent LIBs,which introduces an insight into the future recycling.

关键词： Spent lithium ion battery Regenerating Anode material Succinct procedure High-added value

Intake of tobacco nitrosamines of smokers in various provinces of China and their cancer risk:A meta-analysis

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Journal of Environmental Sciences 2024年第7期141卷 249-260页

作者： xiao Li Zhiwei ye Jun wang Pengfei Lin xiaojin Zhang Shuguang Xie Chao Chen Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhouJiangsu 215163China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Shenzhen Key Laboratory of Organic Pollution Prevention and Control State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyShenzhen 518055China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Science and EngineeringPeking UniversityBeijing 100871China

Nitrosamines are a class of carcinogens which have been detected widely in food,water,some pharmaceuticals as well as *** objectives of this paper include reviewing the basic information on tobacco consumption and nitrosamine contents,and assessing the health risks of tobacco nitrosamines exposure to Chinese *** searched the publications in English from“Web of Science”and those in Chinese from the“China National Knowledge Infrastructure”in 2022 and collected 151 literatures with valid *** content of main nitrosamines in tobacco,including 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK),N-nitrosonornicotine(NNN),N-nitrosoanatabine(NAT),N-nitrosoanabasine(NAB),total tobacco-specific nitrosamines(TSNA),and N-nitrosodimethylamine(NDMA)were *** information of daily tobacco consumption of smokers in 30 provinces of China was also ***,the intakes of NNN,NNK,NAT,NAB,TSNAs,and NDMA via tobacco smoke were estimated as 1534ng/day,591 ng/day,685 ng/day,81 ng/day,2543 ng/day,and 484 ng/day by adult smokers in30 provinces,*** cancer risk(CR)values for NNN and NNK inhalation intake were further calculated as 1.44×10^(-5)and 1.95×10^(-4).The CR value for NDMA intake via tobacco smoke(inhalation:1.66×10^(-4))indicates that NDMA is similarly dangerous in tobacco smoke when compared with the *** China,the CR values caused by average nitrosamines intake via various exposures and their order can be estimated as the following:smoke(3.75×10^(-4))>food(1.74×10^(-4))>drinking water(1.38×10^(-5)).Smokers in China averagely suffer 200%of extra cancer risk caused by nitrosamines in tobacco when compared with non-smokers.

关键词： N-nitrosamine Tobacco Cancer risk Tobacco specific nitrosamines(TSNAs) N-nitrosodimethylamine(NDMA)

Multiperiod optimization of cooling water system with flexible topology network

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Green Chemical Engineering 2024年第4期5卷 461-472页

作者： Bo Liu Ruimei Zhang ye Liu Yufei wang Ali Almansoori xiao Feng School of Chemical Engineering and Environment China University of PetroleumBeijing102249China Department of Chemical Engineering Khalifa University of Science and TechnologyAbu Dhabi127788United Arab Emirates CHN Energy Xinjiang Chemical Co.LTD UrumqiXinjiang830092China School of Chemical Engineering&Technology Xi'an Jiaotong UniversityXi'an710049China

Cooling water systems(CWSs)are extensively utilized in various industries to eliminate the excess heat and converse *** on CWSs mainly concentrated on finding the optimal cooler network *** addition,some works also considered the optimal design under varied operation ***,in these works,once the optimal design of the cooler's network is determined,its arrangement remains fixed and cannot be adapted to accommodate diverse operating *** this work,a flexible topology network concept is proposed to make the adjustment of network structure possible under different operation *** CWS with integrated air cooler and flexible topology network has better overall performance,represented by a mixed integer nonlinear programming(MINLP)model that require advanced tools such as GAMS *** studies revealed that the proposed methodology can realize better energy-saving performance,and improve the economic performance under varied operation *** impact of critical flexible nodes on system configuration and economy is achieved by sensitivity analysis.

关键词： Cooling water systems Flexible network Multiperiod optimization Air cooler

Distributed filtering for time-varying networked systems with sensor gain degradation and energy constraint: a centralized finite-time communication protocol scheme

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Science China(Information Sciences) 2018年第9期61卷 241-255页

作者： ye ZHAO xiao HE Donghua ZHOU National Laboratory for Information Science and Technology (TNList) and Department of Automation Tsinghua University College of Electrical Engineering and Automation Shandong University of Science and Technology

This paper focuses on the distributed filtering problem for a class of time-varying networked systems with sensor gain degradation and energy constrained communication protocol. To satisfy the requirement of power consumption and reduce the schedule computing complexity, centralized cyclic finite-time communication strategy optimization is taken into account. The networked system considered in this paper consists of spatially distributed sensors linked to their neighbor sensors, where each sensor node suffers from different gain degradation, and the transmission decisions of all the communication channels obey the centralized transmission schedule strategy identically. First, we present scattered communication action based on single-sensor transmission modeling with an energy constraint. Subsequently, an optimal communication protocol considering expected average error covariance is derived between the target system and each sensor node over the distributed sensor systems, based on a centralized finite-time scheme. Finally, by transforming the overall estimation error covariance of the systems at each sampling time into quadratic form, a conditionally unbiased least-square recursive distributed filtering technique over the networked system is designed at each sensor node. The system stability condition under such an optimal schedule is also accomplished with bounded covariance. A numerical example is provided to demonstrate the utility and effectiveness of the distributed filtering technique using the proposed optimized energy constrained communication protocol.

关键词： networked systems distributed filtering communication protocol centralized finite-time schedule energy constraint sensor gain degradation

Two new chalcones from Fordia cauliflora

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Chinese Chemical Letters 2010年第7期21卷 818-820页

作者： Zhi Yuan Liang xiao Sheng Yang ye wang xiao Jiang Hao Qian Yun Sun The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang 550002China School of Chemistry and Life Science Guizhou Normal CollegeGuiyang 550003China

Two new chalcones,β,2′,4′,5′-tetramethoxychalcone 1,andβ,2′,5′-trimethoxyfurano[4″,5″：3′,4′]-chalcone 2 were obtainedfrom an ethyl acetate-soluble fraction of ethanol extract of the stem of Fordia *** chem... 详细信息

关键词： Fordia cauliflora Chalcone Chemical structures

Modeling and compensation of hysteresis for pneumatic artificial muscles based on Gaussian mixture models

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Science China(Technological Sciences) 2019年第7期62卷 1094-1102页

作者： XU JiHao xiao MuBang DING ye State Key Laboratory of Mechanical System and Vibration School of Mechanical Engineering Shanghai Jiao Tong University

This paper presents a new data-driven model of length-pressure hysteresis of pneumatic artificial muscles(PAMs) based on Gaussian mixture models(GMMs). By ignoring the high-order dynamics, the hysteresis of PAMs is modeled as a first-order nonlinear dynamical system based on GMMs, and inversion of the model is subsequently derived. Several verification experiments are conducted. Firstly, parameters of the model are identified under low-frequency triangle-wave pressure ***, pressure signals with different amplitudes, shapes and frequencies are applied to the PAM to test the prediction performance of the model. The proposed model shows advantages in identification efficiency and prediction precision compared with a generalized Prandtl–Ishlinskii(GPI) model and a modified generalized Prandtl–Ishlinskii(MGPI) model. Finally, the effectiveness of the inverse model is demonstrated by implementing the feedforward hysteresis compensation in trajectory tracking experiments.

关键词： hysteresis modeling hysteresis compensation pneumatic artificial muscles (PAMs) Gaussian mixture model (GMM)

Risk factors and gene polymorphisms of inflammatory bowel disease in population of Zhejiang,China

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World Journal of Gastroenterology 2011年第1期17卷 118-122页

作者： Zi-Wei wang Feng Ji Wei-Jun Teng xiao-Gang Yuan xiao-Ming ye Department of Digestive Diseases First AffiliatedHospital College of Medicine Zhejiang University Hangzhou310003 Zhejiang Province China

AIM:To identify the risk factors and three single nucleotide polymorphisms(SNPs) of NOD2/CARD15 gene in inflammatory bowel disease(IBD) of the population in Zhejiang,***:A case-control study was conducted using recall questionnaire to collect data on demographic,socioeconomic,lifestyle characteristics and dietary behaviors from 136 determined IBD patients and 136 paired healthy *** regression method was used to screen the statistically significant risk factors for *** polymorphisms of NOD2/CARD15 gene Arg702Trp,Gly908Arg and Leu1007fsinsC were genotyped and further compared between 60 patients with IBD and 60 healthy controls by polymerase chain reaction and restriction fragment length ***:IBD occurred primarily in young and middle-aged *** mean age for IBD patients was 42.6 *** ratio of males to females was 1.23:*** regression indicated a higher statistical significance in milk,fried food and stress compared with the other postulated risk factors for *** of the patients with IBD and healthy controls had heterozygous or homozygous SNPs ***:Milk,fried food and stress are associated with increased risk of *** common variants in NOD2/CARD15 gene are not associated with IBD in China's Zhejiang population.

关键词： Inflammatory bowel disease Risk factors Epidemiology Gene polymorphism NOD2/CARD15 gene

An analysis of the mechanism underlying photocatalytic disinfection based on integrated metabolic networks and transcriptional data

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Journal of Environmental Sciences 2020年第6期32卷 28-37页

作者： xiao-Long Liang Zhan-Min Liang Shuo wang xiao-Hui Chen Yao Ruan Qing-ye Zhang Hong-Yu Zhang Hubei Key Laboratory of Agricultural Bioinformatics College of InformaticsHuazhong Agricultural UniversityWuhan430070PR China

Photocatalytic disinfection has long been used to combat pathogenic ***,the specific mechanism underlying photocatalytic disinfection and its corresponding targets remain *** this study,an analysis of the potential mechanism underlying photocatalytic disinfection was performed based on integrated metabolic networks and transcriptional *** sets of RNA-seq data(wild type and a photocatalysis-resistant mutant mediated by titanium dioxide(TiO2))were processed to constrain the genome scale metabolic models(GSMM)of *** analyzing the metabolic network,the differential metabolic flux of every reaction was computed in constrained GSMM,and several significantly differential metabolic fluxes in reactions were extracted and *** of these reactions were involved in the transmembrane transport of substances and occurred on the inner membrane or were an important component of the cell *** results,which are consistent with the reported information,validated our analysis *** addition,our work also identified other new and valuable metabolic pathways,such as the reaction ALCD2x,which has a great effect on the energy production process under bacterial anaerobic *** DHAK reaction is also related to the metabolic process of *** reactions with large differential metabolic fluxes merit further ***,to provide a strategy to address photocatalysis-resistant mutant bacteria,a metabolic compensation analysis was also *** metabolic compensation analysis results provided suggestions for a combined method that can effectively combat resistant *** method could also be used to explore the mechanisms of drug resistance in other microorganisms.

关键词： Photocatalytic disinfection Genome scale metabolic models(GSMM) RNA-seq analysis Mechanism Metabolic compensation