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Journal of Systems Science & Complexity 2019年第5期32卷 1340-1357页

作者： GAO Jinhai HAO Lina cheng hongtai CAO Ruimin SUN Zhiyong School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Department of Industrial and Manufacturing Systems Engineering The University of Hong KongHong KongChina.

Micro/nano positioning technologies have been attractive for decades in industrial and scientific applications fields. The actuators have inherent hysteresis that can cause system unexpected behave in some extend. In this research, the authors used extented unparallel Prandtl-Ishlinshii(EUPI)models to represent the input-output relationship of a piezo-driven micro position stage. Integral inverse(I-I) compensator is used for compensating the hysteresis characteristics of the micro positioning stage and compared with direct inverse(D-I) compensator and inverse model(I-M) compensator. However,the accuracy and the robustness of the I-I compensator are worse when there is noisy in the system,a novel sliding-mode-like-control with EUPI(SMLC-EUPI) method was proposed and analyzed by different trajectory tracking experiments in Matlab environment. Though the above strategies can alleviate most deviation, the adjustment of the SMLC’s parameters is very complex. So the fuzzy method is used to adjust these parameters and be verified by trajectory tracking experiments. Finally,for validating the proposed control method, the paper did the corresponding experiment in microscope with CMOS and obtained convincing results.

关键词： EUPI fuzzy hysteresis compensation micro position stage sliding-mode-like-control

基于能量的欠驱动双臂机器人悬摆动态伺服控制

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西南交通大学学报 2009年第3期44卷 380-384页

作者：赵旖旎程红太张晓华哈尔滨工业大学电气工程及自动化学院黑龙江哈尔滨150001

针对欠驱动双臂机器人悬摆运动时,摆臂末端对目标点或目标轨迹的跟踪问题,提出动态伺服控制策略.利用灵长类动物悬摆运动的类单摆特性,基于李亚普诺夫稳定性理论,设计了基于能量和双臂空间构型的滑模变结构切换控制律,规划系统末端的动... 详细信息

针对欠驱动双臂机器人悬摆运动时,摆臂末端对目标点或目标轨迹的跟踪问题,提出动态伺服控制策略.利用灵长类动物悬摆运动的类单摆特性,基于李亚普诺夫稳定性理论,设计了基于能量和双臂空间构型的滑模变结构切换控制律,规划系统末端的动态空间轨迹.数值仿真实验验证了所述控制策略的有效性.

关键词：欠驱动双臂机器人悬摆运动控制动态伺服控制 Lyapunov稳定性理论滑模变结构控制

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灵长类仿生机器人悬臂飞跃运动控制研究

信息与控制 2010年第6期39卷 794-800页

作者：张晓华赵旖旎程红太哈尔滨工业大学黑龙江哈尔滨150001 中国空间技术研究院北京100094

研究了双臂式灵长类仿生机器人的悬臂飞跃运动仿生控制问题.基于角动量守恒原理,针对机器人进行悬臂飞跃时目标点的位置,规划机器人的空中姿态及身体旋转.基于逆运动学分析方法,获得起飞时刻系统位姿,提出了基于分层滑模控制的悬摆姿态... 详细信息

研究了双臂式灵长类仿生机器人的悬臂飞跃运动仿生控制问题.基于角动量守恒原理,针对机器人进行悬臂飞跃时目标点的位置,规划机器人的空中姿态及身体旋转.基于逆运动学分析方法,获得起飞时刻系统位姿,提出了基于分层滑模控制的悬摆姿态控制策略.仿真实验表明所述控制策略可以实现双臂悬摆机器人的悬臂飞跃运动控制.

关键词：双臂悬摆机器人悬臂飞跃运动分层滑模控制仿生悬摆

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基于ROS和QoS的云机器人研究

机械与电子 2020年第7期38卷 63-70页

作者：张伟郝丽娜程红太高乾东北大学机械工程与自动化学院辽宁沈阳110819

针对在云机器人系统中,机器人端和云端之间消息需要转换格式才能传递,对异构机器人的兼容性较差,并且对网络环境的鲁棒性有待提高的情况,提出了基于ROS并只在本地端部署主节点的云机器人系统CloudROS。首先,本地和云端的服务均采用标准... 详细信息

针对在云机器人系统中,机器人端和云端之间消息需要转换格式才能传递,对异构机器人的兼容性较差,并且对网络环境的鲁棒性有待提高的情况,提出了基于ROS并只在本地端部署主节点的云机器人系统CloudROS。首先,本地和云端的服务均采用标准的ROS节点形式进行封装,云端的服务节点可以动态加入到机器人端的ROS网络,节点之间的消息格式无需进行转换,提高了系统的兼容性;然后,在云端采用了授权认证和Docker虚拟化技术,保证了系统的安全性;最后,提出了服务质量(QoS)监测与调节策略,通过动态调整任务参数或切换本地与云端的服务,使QoS保持一个较优的值。实验结果表明,CloudROS可以有效地把机器人的计算任务卸载到云端,使机器人的性能得到提升,并对网络环境具有较好的鲁棒性。

关键词：云机器人 ROS 服务质量服务调度

Boosting polysulfide redox conversion of Li-S batteries by one-step-synthesized Co-Mo bimetallic nitride

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Journal of Energy Chemistry 2021年第10期30卷 336-346,I0010页

作者： Yingying Yan hongtai Li Chen cheng Tianran Yan Wenping Gao Jing Mao Kehua Dai Liang Zhang Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123JiangsuChina School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina College of Chemistry Tianjin Normal UniversityTianjin 300387China

Lithium-sulfur(Li-S)batteries are considered as one of the most promising next generation energy storage systems due to the high theoretical specific capacity,low cost,and environmental ***,the notorious shuttle effect of polysulfides hinders the practical application of Li-S ***,we have rationally designed and synthesized sea urchin-like Co-Mo bimetallic nitride(Co_(3) MO_(3) N)in the absence of additional nitrogen sources with only one step,which was applied as the sulfur host materials for Li-S *** results indicate that Co_(3) Mo_(3) N can efficiently anchor and catalyze the conversion of polysulfides,thus accelerating the electrochemical reaction kinetics and enabling prominent electrochemical *** a consequence,the S@Co_(3) Mo_(3) N cathode exhibits a high rate performance of 705 mAh g^(-1) at 3 C rate and an excellent cycling stability with a low capacity fading rate of 0.08%per cycle at 1 C over 600 *** at a high sulfur loading of 5.4 cmg cm^(-2),it delivers a high initial areal capacity of 4.50 mAh cm^(-2) which is still retained at 3.64 mAh cm^(-2) after 120 ***,the catalytic mechanism and structural stability of Co_(3) Mo_(3) N during cycling were elucidated by a combination of X-ray photoelectron spectroscopy and X-ray absorption fine *** work highlights the strategy of structure-catalysis engineering of bimetallic nitride,which is expected to have a wide application in Li-S batteries.

关键词： Lithium-sulfur batteries Co3Mo3N Shuttle effect Catalytic effect XAFS

Promoting effect of microwave irradiation on CeO2-TiO2 catalyst for selective catalytic reduction of NO by NH3

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Journal of Rare Earths 2020年第1期38卷 59-69页

作者： Jie cheng Liyun Song Rui Wu Shining Li Yanming Sun hongtai Zhu Wenge Qiu Hong He Key Laboratory of Beijing on Regional Air Pollution Control And Beijing Key Laboratory for Green Catalysis and SeparationBeijing University of TechnologyBeijing 100124China Collaborative Innovation Centre of Electric Vehicles in Beijing Beijing 100081China

In this work we prepared several CeO2-TiO2 catalysts for the NH3-SCR reactionusing co-precipitation with assistance of microwave *** catalytic NH3-SCR activities over CeO2-TiO2 catalysts at low temperatures are largely enhanced by the treatment of microwave irradiation,the operation temperature window is also *** better understanding the promotion mechanism,the catalyst prepared by conventional co-precipitation with and without microwave irradiation treatment was characterized with H2-TPR,NH3-TPD,XPS,XRD and *** irradiation treatment accelerates the crystallite rate of CeO2-TiO2 catalysts,and greatly enlarges their surface area by adjusting their *** resistance to SO2 and H2O is also improved via regulating the hierarchical pore structure by the microwave *** irradiation treatment can also improve the redox property and increase the acid sites over the catalyst *** result of in situ DRIFTS suggests that the microwave irradiation treatment generates more Br?nsted acid sites on CeO2-TiO2-2 h catalyst,helpful in SCR *** results show that after microwave irradiation on the CeO2-TiO2 catalysts,the surface demonstrates an elevated concentration of chemisorbed oxygen,consequently leading to better oxidation of NO to ***,the molar ratio of Ce3+/Ce4+has been elevated after being treated by microwave irradiation,a vital factor in enhancing the NH3-SCR activities.

关键词： SCR catalyst NH3-SCR Low temperature CeO2-TiO2 Microwave irradiation Rare earths

Effect of niobium content on irradiation microstructure and hardening in FeCrAl-based alloys

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Journal of Materials Science & Technology 2021年第36期95卷 181-192页

作者： Xiong Zhou Hui Wang Liping Guo Yiheng Chen Fang Li Yunxiang Long cheng Chen Ziyang Xie hongtai Luo Shaobo Mo Hubei Nuclear Solid Physics Key Laboratory Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education and School of Physics and TechnologyWuhan UniversityWuhan 430072China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China School of Mechanical Engineering Chengdu UniversityChengdu 610106China Analysis and Testing Center of Wuhan University Wuhan UniversityWuhan 430072China

Iron-chromium-aluminum(FeCrAl)alloys with different content of niobium(Nb)—0,0.4 wt%,0.8 wt%,and 1.2 wt%—were designed and *** samples were then irradiated with 2.4 MeV Fe^(2+)ion to the dose of 1 and 15 displacements per atom(dpa)at 400℃.The formations of dislocation loops induced by self-ion irradiation in these alloys were investigated by transmission electron microscopy(TEM).Nano-indentation tests were used to assess the hardness and irradiation hardening of *** the samples before irradiation,the(Fe,Cr)_(2)(Nb,Mo)Laves phases density and the nano-indentation hardness increased with increasing Nb content of the *** irradiation to 1 and 15 dpa,both of a/2and adislocation loops were produced but no voids orα’phase were found in all *** increasing Nb content of the samples,the size of dislocation loops increased first and then decreased,while the total volume number density decreased and then *** fraction of adislocation loops increased first and then decreased with increasing Nb content,and increased with increasing irradiation *** networks and the amorphization of the Laves phases were observed in the samples with irradiation dose of 15 *** hardening of Nb free samples was two to four times that of Nb containing samples,and the irradiation hardening increased with increasing Nb content of Nb containing *** experimental results indicate that the increase of Nb content in Fe Cr Al alloys can increase the density of Laves phases,leading to the decrease of Mo content and increase of Cr content in the *** competition between the two types of solutes affects the nucleation and growth of the dislocation loops.

关键词： FeCrAl alloy Dislocation loops Radiation damage Accident tolerant fuel cladding Laves phase

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基于相关滤波的高速图像旋转运动估计算法

激光与光电子学进展 2023年第10期60卷 259-264页

作者：杨赟辉朱鸿泰程虎刘丹中科芯集成电路有限公司江苏无锡214072

针对载体姿态变化引起的相机旋转运动,提出一种基于相关滤波的高速图像旋转运动估计算法(GPCF)。在灰度投影法的基础上,该算法采用相关滤波代替互相关运算进行角度估计。通过构建循环移位矩阵,扩充负样本数量,有效提高旋转运动估计的精... 详细信息

针对载体姿态变化引起的相机旋转运动,提出一种基于相关滤波的高速图像旋转运动估计算法(GPCF)。在灰度投影法的基础上,该算法采用相关滤波代替互相关运算进行角度估计。通过构建循环移位矩阵,扩充负样本数量,有效提高旋转运动估计的精度和鲁棒性。构建噪信比公式,以定量分析噪声对旋转运动估计算法的影响程度。理论分析和实验结果均表明,GPCF能够实时估计图像序列旋转角度,且精度和稳定性相比灰度投影法具有较大提升。

关键词：图像处理旋转运动估计灰度投影法互相关相关滤波

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轻量级红外弱小目标检测算法

激光与光电子学进展 2022年第16期59卷 272-278页

作者：章琦朱鸿泰程虎张俊张晔中国电子科技集团公司第五十八研究所江苏无锡214072

针对现有方法难以在复杂背景下对缺乏内在特征的红外弱小目标进行检测并且存在检测耗时较高等问题,提出了一种适用于嵌入式边缘计算设备的红外弱小目标检测算法。将小目标检测问题转化为语义分割问题,模型使用轻量级主干网络提取特征,... 详细信息

针对现有方法难以在复杂背景下对缺乏内在特征的红外弱小目标进行检测并且存在检测耗时较高等问题,提出了一种适用于嵌入式边缘计算设备的红外弱小目标检测算法。将小目标检测问题转化为语义分割问题,模型使用轻量级主干网络提取特征,设计基于上下文调制的跨层间的特征融合方式,用于交换高层语义和低层细节,引入基于通道和位置的双注意力机制突出特征图中的弱小目标。通过实验验证了提出算法模型相较于现有先进的算法在复杂场景下具有更好的检测效果、更低的虚警以及更少的耗时等优势,且该模型大小只有100 KB,可以达到20 frame/s视频流实时检测,方便嵌入式部署及实际应用。

关键词：成像系统红外弱小目标检测语义分割注意力机制上下文调制 MobileNet-V3

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H Odé剪切变形理论在纳米尺度的表象

地球科学 2018年第5期43卷 1518-1523页

作者：孙岩琚宜文黄骋周巍晁洪太王志才南京大学地球科学与工程学院江苏南京210093 中国科学院大学地球与行星科学学院北京100049 山东省地震局山东济南250014

通常认为岩石是被剪破或张裂的,那么,为何我们能寻觅到位于同压力垂直方向的破裂构造呢?H Odé剪切变形理论给出一个精辟的回答:在塑性或粘-弹性变形中,由于介质的分异作用,存在一个从屈服条件中获得的速度不连续性,这样,其介质就能沿... 详细信息

通常认为岩石是被剪破或张裂的,那么,为何我们能寻觅到位于同压力垂直方向的破裂构造呢?H Odé剪切变形理论给出一个精辟的回答:在塑性或粘-弹性变形中,由于介质的分异作用,存在一个从屈服条件中获得的速度不连续性,这样,其介质就能沿着等速的特征面剪切滑移.该理论亦称为塑性剪切作用准则,之前是从宏观-直观力学表象予以验证,如构造挤压带的破裂面、正压力下Griffith裂隙端点裂开和垂直压力下的碎裂流动等.进而,我们对花岗岩标本实施高温/高压实验,并取其位于轴压垂直方向裂隙的薄壳表层做扫描电镜观测.然后把从其表层观察的具有H Odé力学表象的微纳米现象,同一般剪切作用的屈服效应结构,从3个方面相比较鉴别.(1)粘-弹性变形:高温-高压的实验样品更容易产生塑性压缩容积流动,不仅具粘性也具弹性变形,随之,样品可展现纳米涂层作用和纳米分层作用.(2)纳米尺度结构:纳米尺度颗粒能成为单一纳米粒-纳米线-纳米层结构,且复体的纳米粒可细分成粒状的、线状的和片粒状的结构等.(3)有序组构:尽管H Odé破裂的粒化流动和纹理流动的优选方位,同普通剪切作用相比,处于弱势范畴,然而综合分析观之,这两者的屈服特征是完全一致的.反之,我们应用H Odé剪切理论去研究一些非常规的变形现象,必能拓展纳米地质学的研讨范畴和认知能力.

关键词： H Odé剪切变形纳米尺度粘-弹性变形三轴压力实验有序组构构造地质