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Open-loop and closed-loop D^(α)-type iterative learning control for fractional-order linear multi-agent systems with state-delays

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Journal of Systems Engineering and Electronics 2021年第1期32卷 197-208页

作者： LI Bingqiang LAN Tianyi ZHAO Yiyun lyu shuaishuai School of Automation Northwestern Polytechnical UniversityXi’an 710129China School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi’an 710021China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

This study focuses on implementing consensus tracking using both open-loop and closed-loop Dα-type iterative learning control(ILC)schemes,for fractional-order multi-agent systems(FOMASs)with *** desired trajectory is constructed by introducing a virtual leader,and the fixed communication topology is considered and only a subset of followers can access the desired *** each control scheme,one controller is designed for one agent *** to the tracking error between the agent and the virtual leader,and the tracking errors between the agent and neighboring agents during the last iteration(for open-loop scheme)or the current running(for closed-loop scheme),each controller continuously corrects the last control law by a combination of communication weights in the topology to obtain the ideal control *** the rigorous analysis,sufficient conditions for both control schemes are established to ensure that all agents can achieve the asymptotically consistent output along the iteration axis within a finite-time *** numerical simulation results demonstrate the effectiveness of the control schemes,and provide some meaningful comparison results.

关键词： multi-agent system fractional-order consensus control iterative learning control virtual leader state-delay

Polymer-encapsulated metal complex catalysts:An emerging and efficient platform for electrochemical CO_(2) reduction

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Journal of Materials Science & Technology 2024年第5期172卷 33-50页

作者： Yingshuo Liu shuaishuai lyu Fuli Wen Weixuan Nie Shuqing Wang Sinopec Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China School of Engineering Westlake UniversityHangzhou 310024China

Over the past decade,electrocatalytic reduction of CO_(2)has gained substantial ***,hardly any of the previous reviews have focused on the systematic discussion of polymer-molecular catalyst composites as an emerging system for the electrochemical transformation of CO_(2)to value-added *** this review,we first give a brief overview of the general features of solid-state and molecular catalysts,and then advance the discussion to polymer-catalyst composite systems,with particular emphasis on polymer-encapsulated molecular catalysts,where the coordination environment surrounding molecular catalysts can be modified via polymer encapsulation to promote the overall performance of CO_(2)*** elucidation of the possible reaction mechanisms of this emerging electrocat-alytic system along with proposed optimization strategies is also summarized and discussed based on recently published reports,followed by the challenges and prospects of their industrial applications at the end of this *** this review,we hope the audience can gain a comprehensive understanding of the electrocatalytic mechanism of the coordinating polymers and valuable insights into engineering the microenvironment surrounding the metal complexes for potential future research directions.

关键词： Polymer-molecular catalyst composite Polymer encapsulation Coordination environment CO_(2)electrocatalysis Electrocatalytic mechanism

Manipulating metal-support interactions of metal catalysts for Fischer-Tropsch synthesis

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Chinese Journal of Chemical Engineering 2021年第7期34卷 220-230页

作者： Qingpeng Cheng Yunhao Liu shuaishuai lyu Ye Tian Qingxiang Ma Xingang Li Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) State Key Laboratory of Chemical EngineeringTianjin Key Laboratory of Applied Catalysis Science and TechnologySchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Advanced Membranes and Porous Materials Center Physical Sciences and Engineering DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering Ningxia UniversityYinchuan 750021China School of Chemical and Biological Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

For supported metal catalyst systems,the impact on catalysis originates from the interaction between metal nanoparticles and their ***-support interactions(MSI)can change electronic properties,geometric morphologies,or chemical compositions of metal nanoparticles to make active sites have specific properties and catalytic ***-Tropsch synthesis(FTS)is one of the most effective ways to convert cheap non-petroleum-based carbon sources into high value-added chemicals or ultraclean liquid *** this review,we summarize and classify the impact of MSI on the catalytic activity,selectivity and stability of FTS *** strategies to tune MSI are introduced in detail,and the recent development of high-efficiency FTS catalysts through the manipulation of SMI strategies has been *** is emphasized that the active metal sites,which are endowed with special functions by MSI,can change the strength of adsorption bond of adsorbates,consequently controlling the product distribution.

关键词： Metal-support interactions Fischer-Tropsch synthesis Modification strategies Activity Selectivity

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电动加载系统分数阶迭代学习复合控制

北京航空航天大学学报 2016年第9期42卷 1944-1951页

作者：吕帅帅林辉西北工业大学自动化学院西安710129

针对电动加载系统存在多余力矩扰动的问题,提出一种以位置闭环和力矩闭环为反馈控制、迭代学习控制为补偿控制的复合控制策略。为提高加载系统动态性能及降低建立模型的复杂性,驱动永磁同步电机采用直接转矩控制方式,建立加载系统频域... 详细信息

针对电动加载系统存在多余力矩扰动的问题,提出一种以位置闭环和力矩闭环为反馈控制、迭代学习控制为补偿控制的复合控制策略。为提高加载系统动态性能及降低建立模型的复杂性,驱动永磁同步电机采用直接转矩控制方式,建立加载系统频域模型。在位置闭环和力矩闭环采用分数阶PIλD~μ控制器代替常规PID控制器,迭代学习补偿控制采用分数阶迭代学习控制器,利用分数阶微积分的信息记忆特性提高控制系统的动态性能和鲁棒性,通过理论分析给出分数阶PD型迭代学习控制器的收敛条件。对正弦和梯形波载荷进行力矩加载实验及多余力矩抑制实验,验证了该控制方法的有效性。

关键词：电动加载系统分数阶PIλDμ 分数阶迭代学习控制多余力矩高精度力矩伺服

Boosting Fischer-Tropsch Synthesis via Tuning of N Dopants in TiO_(2)@CN-Supported Ru Catalysts

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Transactions of Tianjin University 2024年第1期30卷 90-102页

作者： Xincheng Li Yunhao Liu Dejian Zhao shuaishuai lyu Jingwei Ye Xiaoshen Li Peipei Wu Ye Tian Yingtian Zhang Tong Ding Song Song Qingpeng Cheng Xingang Li State Key Laboratory of Chemical Engineering Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Haihe Laboratory of Sustainable Chemical TransformationsTianjin Key Laboratory of Applied Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Zhejiang Institute of Tianjin University Shaoxing 312300China Sinopec Research Institute of Petroleum Processing Co. LTDBeijing 100083China Physical Sciences and Engineering Division Advanced Membranes and Porous Materials(AMPM)CenterKing Abdullah University of Science and Technology(KAUST)23955-6900 ThuwalSaudi Arabia

Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such as Fischer-Tropsch synthesis(FTS).Herein,we engineered ruthenium(Ru)FTS catalysts supported on N-doped carbon overlayers on TiO_(2)*** regulating the carbonization temperatures,we successfully controlled the types and contents of N dopants to identify their impacts on metal-support interactions(MSI).Our fi ndings revealed that N dopants establish a favorable surface environment for electron transfer from the support to the Ru ***,pyridinic N demonstrates the highest electron-donating ability,followed by pyrrolic N and graphitic *** addition to realizing excellent catalytic stability,strengthening the interaction between Ru sites and N dopants increases the Ru^(0)/Ru^(δ+)ratios to enlarge the active site numbers and surface electron density of Ru species to enhance the strength of adsorbed ***,it improves the catalyst’s overall performance,encompassing intrinsic and apparent activities,as well as its ability for carbon chain ***,the as-synthesized Ru/TiO_(2)@CN-700 catalyst with abundant pyridine N dopants exhibits a superhigh C_(5+)time yield of 219.4 mol CO/(mol Ru·h)and C_(5+)selectivity of 85.5%.

关键词： Fischer-Tropsch synthesis N-doped carbon materials Ruthenium catalyst Pyridinic N Metal-N interaction

Spacial hindrance induced recovery of over-poisoned active acid sites in pyridine-modified H-mordenite for dimethyl ether carbonylation

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Chinese Journal of Catalysis 2019年第6期40卷 895-904页

作者： Na Zhao Ye Tian Lifu Zhang Qingpeng Cheng shuaishuai lyu Tong Ding Zhenpeng Hu Xinbin Ma Xingang Li Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Tianjin Key Laboratory of Applied Catalysis Science and Engineering Tianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Zeolite catalysts,such as H-mordenite(H-MOR),are readily deactivated by coke deposition in carbonylation *** modification of H-MOR can improve its stability but can lead to an undesirable loss in catalytic ***,we report the intrinsic impact of the pyridine adsorption behavior on H-MOR and the spacial hindrance of the zeolite frameworks on dimethyl ether(DME)carbonylation at a molecular *** discovered that acid sites at O2 positions,located on common walls of eight-membered ring(8-MR)side pockets and 12-MR channels,were active in DME carbonylation,but were unfortunately poisoned during pyridine *** functional theory calculations revealed that the pyridine-poisoned acid sites at the O2 positions could be easily regenerated due to the spacial hindrance of the zeolite ***,they can be facilely regenerated by proper thermal treatment,which induces 60%promotion in the catalytic activity along with a high *** findings demonstrate the determining role of O2 positions in H-MOR for DME carbonylation and provide a new avenue for the rational design of other efficient zeolite-relevant catalytic systems.

关键词： H-mordenite Pyridine modification Dimethyl ether Carbonylation Regeneration Spacial hindrance

基于BF-Net与孪生分差的飞机结构裂纹检测方法

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振动．测试与诊断 2023年第1期43卷 9-15,194页

作者：王叶子吕帅帅杨宇王彬文中国飞机强度研究所西安710065

针对目前飞机结构疲劳试验损伤检测中计算机视觉识别模型面临的主要问题是如何从同为毫米级的表面纹理、划痕、污迹中识别出疲劳裂纹,提出了基于双向融合网络(bidirectional fusion network,简称BF-Net)和孪生分差的飞机结构裂纹检测方... 详细信息

针对目前飞机结构疲劳试验损伤检测中计算机视觉识别模型面临的主要问题是如何从同为毫米级的表面纹理、划痕、污迹中识别出疲劳裂纹,提出了基于双向融合网络(bidirectional fusion network,简称BF-Net)和孪生分差的飞机结构裂纹检测方法。首先,采用分级检测策略,提取出可能出现裂纹的重点区域;其次,设计面向微小目标识别的BF-Net,通过自上而下和自下而上的特征融合操作从区域图像中自动获取高质量的裂纹特征信息;最后,采用孪生分差法,基于重点区域的自身特征信息以及与模板间的特征差异信息来综合判别裂纹。试验结果表明,该方法能够实现对微小裂纹的精确检测,为飞机结构疲劳试验中裂纹的自动化检测提供了有效的技术途径。

关键词：裂纹检测计算机视觉深度学习双向融合网络孪生分差

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基于改进Mask-RCNN的飞行器结构裂纹自动检测方法

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振动．测试与诊断 2021年第3期41卷 487-494,620页

作者：吕帅帅杨宇王彬文裴连杰中国飞机强度研究所西安710065

计算机视觉的裂纹自动识别算法在飞机结构疲劳试验中具有较好的工程应用前景,但由于飞机结构构型多样及疲劳试验环境复杂,传统方法的裂纹识别准确率难以满足要求。针对此问题,设计了一种基于关键结构定位的检测策略,并以目标分割算法掩... 详细信息

计算机视觉的裂纹自动识别算法在飞机结构疲劳试验中具有较好的工程应用前景,但由于飞机结构构型多样及疲劳试验环境复杂,传统方法的裂纹识别准确率难以满足要求。针对此问题,设计了一种基于关键结构定位的检测策略,并以目标分割算法掩码-区域卷积神经网络(Mask-regionconvolutionalneuralnetwork,简称Mask-RCNN)为基础对模型架构和非极大值抑制模块进行了适应性改进,提出了一种裂纹自动识别方法。该方法具有主动避开干扰因素、对图片质量要求较低的特点,同时利用Mask-RCNN将像素信息引入参数优化的特性,具备更高的识别准确率。在元件疲劳试验中,该方法对铆钉、裂纹的识别准确率分别为100%和87.5%,相较于现有方法优势显著。

关键词：机器视觉裂纹深度学习目标分割算法掩码‐区域卷积神经网络

基于改进FaceNet的飞行器结构裂纹识别方法

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航空学报 2022年第6期43卷 341-349页

作者：吕帅帅杨宇王彬文殷晨飞中国飞机强度研究所西安710065

基于计算机视觉的裂纹自动识别算法在飞机全尺寸疲劳试验中具有较好的工程应用前景。但由于飞机结构构型多样、疲劳试验环境复杂,直接应用现有的目标检测算法会存在较高的误判率。因此,提出一种基于关键部位状态对比的裂纹识别方法,以... 详细信息

基于计算机视觉的裂纹自动识别算法在飞机全尺寸疲劳试验中具有较好的工程应用前景。但由于飞机结构构型多样、疲劳试验环境复杂,直接应用现有的目标检测算法会存在较高的误判率。因此,提出一种基于关键部位状态对比的裂纹识别方法,以人脸识别模型FaceNet为基础,利用对比机制消除结构表面纹理、划痕等干扰因素的影响,并通过对裂纹数据结构和特征分布规律的分析,对FaceNet模型的样本生成规则、网络架构和损失函数进行了适应性改进。该方法具有对裂纹敏感、对图像质量要求低的特点。在疲劳试验环境中,该方法对长度为0.2~5 mm裂纹的检测准确率为97.6%,相较于现有方法优势明显。

关键词：疲劳试验计算机视觉裂纹深度学习 FaceNet 目标检测