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Composite Nonlinear Bilateral Control for Teleoperation Systems With External Disturbances

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IEEE/CAA Journal of Automatica Sinica 2019年第5期6卷 1220-1229页

作者： Zhenhua Zhao jun yang Shihua Li Wen-Hua Chen the College of Automation engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China the school of Automation Southeast UniversityKey Laboratory of Measurement and Control of School of Computer Science and Engineering (CSE)Ministry of EducationNanjing 210096China the Department of Aeronautical and Automotive engineering Loughborough UniversityLoughboroughLE11 3TUUK

This paper presents a new composite nonlinear bilateral control method based on the nonlinear disturbance observer(NDOB) for teleoperation systems with external disturbances. By introducing the estimations of NDOB and systems' nominal nonlinear dynamics into controller design, a NDOB based composite nonlinear bilateral controller is constructed to attenuate the influence of disturbance and uncertain nonlinearities. As compared with the existing bilateral control methods which usually achieve force haptic(i.e., contact force tracking)through a passive way, the newly proposed method has two major merits: 1) asymptotical convergence of both position and force tracking errors is guaranteed;2) disturbance influence on force tracking error dynamics is rejected through the direct feedforward compensation of disturbance estimation. Simulations on a nonlinear teleoperation system are carried out and the results validate the effectiveness of the proposed controller.

关键词： Bilateral control disturbance observer force haptic teleoperation

A Task Scheduling Algorithm Based on Clustering Pre-processing in Space-Based information Network

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Chinese Journal of Electronics 2024年第1期33卷 217-230页

作者： Yufei WANG jun LIU Shengnan ZHANG Sai XU Jingyi WANG school of computer Science and engineering Northeastern University

With the diversification of space-based information network task requirements and the dramatic increase in demand, the efficient scheduling of various tasks in space-based information network becomes a new challenge. To address the problems of a limited number of resources and resource heterogeneity in the space-based information network, we propose a bilateral pre-processing model for tasks and resources in the scheduling pre-processing stage. We use an improved fuzzy clustering method to cluster tasks and resources and design coding rules and matching methods to match similar categories to improve the clustering effect. We propose a space-based information network task scheduling strategy based on an ant colony simulated annealing algorithm for the problems of high latency of space-based information network communication and high resource dynamics. The strategy can efficiently complete the task and resource matching and improve the task scheduling performance. The experimental results show that our proposed task scheduling strategy has less task execution time and higher resource utilization than other algorithms under the same experimental conditions. It has significantly improved scheduling performance.

关键词： Scheduling algorithms Heuristic algorithms Clustering methods Clustering algorithms Simulated annealing Dynamic scheduling Search problems

A Fast Fractal Image Compression Coding Method

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Journal of Shanghai University(English Edition) 2001年第1期5卷 57-59页

作者： XU Chang man 1, ZHANG Zhao yang school of Communication and information engineering, Shanghai University, Shanghai 200072, china school of Communication and information engineering Shanghai University Shanghai China

Fast algorithms for reducing encoding complexity of fractal image coding have recently been an important research topic. Search of the best matched domain block is the most computation intensive part of the fractal encoding process. In this paper, a fast fractal approximation coding scheme implemented on a personal computer based on matching in range block's neighbours is *** results show that the proposed algorithm is very simple in implementation, fast in encoding time and high in compression ratio while PSNR is almost the same as compared with Barnsley's fractal block coding .

关键词： neighbour fractal block coding range block,domain block iterated function system

Fine classification of rice paddy using multitemporal compact polarimetric SAR C band data based on machine learning methods

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Frontiers of Earth Science 2024年第1期18卷 30-43页

作者： Xianyu GUO junjun YIN Kun LI Jian yang Huimin ZOU Fukun yang school of computer and Communication engineering University of Science and Technology BeijingBeijing 100083China Aerospace information Research Institute Chinese Academy of SciencesBeijing 100094China Department of Electronic engineering Tsinghua UniversityBeijing 100084China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China

Rice is an important food crop for human *** distinguishing different varieties and sowing methods of rice on a large scale can provide more accurate information for rice growth monitoring,yield estimation,and phenological monitoring,which has significance for the development of modern *** polarimetric(CP)synthetic aperture radar(SAR)provides multichannel information and shows great potential for rice monitoring and ***,the use of machine learning methods to build classification models is a controversial *** this paper,the advantages of CP SAR data,the powerful learning ability of machine learning,and the important factors of the rice growth cycle were taken into account to achieve high-precision and fine classification of rice ***,CP SAR data were simulated by using the seven temporal RADARSAT-2 C-band data ***,20-two CP SAR parameters were extracted from each of the seven temporal CP SAR data *** addition,we fully considered the change degree of CP SAR parameters on a time scale(ΔCP_(DoY)).Six machine learning methods were employed to carry out the fine classification of rice *** results show that the classification methods of machine learning based on multitemporal CP SAR data can obtain better results in the fine classification of rice paddies by considering the parameters ofΔCP_(DoY).The overall accuracy is greater than 95.05%,and the Kappa coefficient is greater than *** them,the random forest(RF)and support vector machine(SVM)achieve the best results,with an overall accuracy reaching 97.32%and 97.37%,respectively,and Kappa coefficient values reaching 0.965 and 0.966,*** the two types of rice paddies,the average accuracy of the transplant hybrid(T-H)rice paddy is greater than 90.64%,and the highest accuracy is 95.95%.The average accuracy of direct-sown japonica(D-J)rice paddy is greater than 92.57%,and the highest accuracy is 96.13%.

关键词： compact polarimetric(CP)SAR rice paddy machine learning fine classification multitemporal

平滑注意力与谱上采样细化的非等距三维点云模型对应关系计算

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电子与信息学报 2024年第8期46卷 3285-3294页

作者：杨军张思洋吴衍兰州交通大学电子与信息工程学院兰州730070 兰州交通大学测绘与地理信息学院兰州730070 福建技术师范学院大数据与人工智能学院福清350300

为了解决非等距3维点云模型对应关系计算易受模型大尺度形变影响而导致对应失真、准确率低且平滑性差的问题,该文提出一种结合平滑注意力与谱上采样细化的非等距3维点云模型对应关系计算新方法。首先,利用点所在表面的几何特征信息设计... 详细信息

为了解决非等距3维点云模型对应关系计算易受模型大尺度形变影响而导致对应失真、准确率低且平滑性差的问题,该文提出一种结合平滑注意力与谱上采样细化的非等距3维点云模型对应关系计算新方法。首先,利用点所在表面的几何特征信息设计平滑注意力机制与平滑感知模块,提高特征对大尺度形变区域非刚性变换的感知能力;其次,将深度函数映射模块与平滑正则化约束相结合,提升函数映射计算结果的平滑性;最后,在谱上采样细化模块中,以多分辨率重建的方式得到最终的逐点映射结果。实验结果表明,与已有算法相比,本算法在FAUST、SCAPE和SMAL数据集上构建的对应关系测地误差最小,处理大尺度形变模型时,能够提升逐点映射的平滑性和全局准确率。

关键词：对应关系非等距3维模型平滑注意力函数映射谱上采样细化

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优化谱对齐的三维模型簇一致性对应关系计算

哈尔滨工业大学学报 2024年第5期56卷 84-92页

作者：吴衍杨军张思洋兰州交通大学电子与信息工程学院兰州730070 福建技术师范学院大数据与人工智能学院福建福清350300 兰州交通大学测绘与地理信息学院兰州730070

为了解决非刚性三维模型簇对应关系计算准确率低、一致性差,且难以实现双射的问题,提出了一种采用优化谱对齐算法和规范一致潜在基的非刚性三维模型簇对应关系计算新方法。首先,利用函数映射的伴随算子实现模型间谱域信息的对齐,计算模... 详细信息

为了解决非刚性三维模型簇对应关系计算准确率低、一致性差,且难以实现双射的问题,提出了一种采用优化谱对齐算法和规范一致潜在基的非刚性三维模型簇对应关系计算新方法。首先,利用函数映射的伴随算子实现模型间谱域信息的对齐,计算模型簇中每个模型对的函数映射矩阵,解决函数映射与逐点映射方向不一致的问题;其次,使用改进的模型映射集合算法为每个模型对的函数映射矩阵赋予相应权重,降低初始化参数的噪声对模型簇对应关系计算结果的影响;最后,在模型簇的对应关系计算过程中加入极限模型的规范一致潜在基,极限模型可以看成模型簇中所有模型的类型结构,是一个具有几何可变性的中间模型,提高算法的一致性和双射性。实验结果表明:与已有算法相比,本算法在FAUST、SCAPE、TOSCA和SHERC’16 Topology数据集上构建的对应关系测地误差最小,能够减少初始化参数的噪声,解决模型自身对称性影响对应关系计算的问题,更加精确地构建出具有一致性和双射性的非刚性三维模型簇对应关系。

关键词：对应关系非刚性三维模型簇优化谱对齐规范一致潜在基函数映射

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Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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Science china(information Sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,yang XiaoLong1,2 & LONG KePing2 1 Research Center for Optical Internet and Mobile information Networks(COIMIN),University of Electronic Science and Technology of china,Chengdu 611731,china 2 school of computer and Communications engineering,University of Science and Technology Beijing,Beijing 100083,china Research Center for Optical Internet and Mobile information Networks (COIMIN) University of Electronic Science and Technology of China Chengdu China school of computer and Communications engineering University of Science and Technology Beijing Beijing China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

可学习动态分组卷积神经网络的大规模点云分割

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计算机工程与应用 2024年第10期60卷 217-226页

作者：康玥杨军兰州交通大学自动化与电气工程学院兰州730070 兰州交通大学电子与信息工程学院兰州730070

针对现有大规模点云语义分割算法提取特征时冗余干扰信息过多,导致神经网络分割性能较差的问题,提出可学习动态分组卷积神经网络架构,高效准确地实现大规模点云分割。对输入点云以分组的方式进行局部几何特征提取,并通过动态筛选和修剪... 详细信息

针对现有大规模点云语义分割算法提取特征时冗余干扰信息过多,导致神经网络分割性能较差的问题,提出可学习动态分组卷积神经网络架构,高效准确地实现大规模点云分割。对输入点云以分组的方式进行局部几何特征提取,并通过动态筛选和修剪冗余特征通道来减少无用特征信息对神经网络特征识别的干扰,进一步提高网络模型语义分割精度。构建位置编码模块,将点云位置特征映射到高维频域空间,使神经网络充分挖掘点云频域特征信息,增强特征的丰富性。对提取到的局部几何特征和全局单点位置特征进行融合,并构建可学习动态分组卷积神经网络,完成解码得到最终分割结果。实验结果表明,该算法在大规模点云分割数据集S3DIS和SemanticKITTI上的mIoU分别为69.6%和58.3%。与现有点云语义分割方法相比,所提出的网络模型具有更高的分割准确率和较低的参数量。

关键词：大规模点云语义分割可学习动态分组卷积位置编码

基于自适应平滑度策略的三维模型分类神经架构搜索

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智能科学与技术学报 2024年第2期6卷 272-280页

作者：周鹏杨军兰州交通大学电子与信息工程学院甘肃兰州730070 兰州交通大学测绘与地理信息学院甘肃兰州730070

针对人工设计三维模型分类网络架构过度依赖专家经验且泛化能力较差的问题,提出了一种自适应平滑度策略的神经架构搜索方法。首先,使用改进候选操作选择策略和连续松弛化方法将离散的搜索空间连续化,并利用权重共享机制提高搜索效率。其... 详细信息

针对人工设计三维模型分类网络架构过度依赖专家经验且泛化能力较差的问题,提出了一种自适应平滑度策略的神经架构搜索方法。首先,使用改进候选操作选择策略和连续松弛化方法将离散的搜索空间连续化,并利用权重共享机制提高搜索效率。其次,在损失函数中添加自适应平滑度策略的正则化,由温度参数控制损失函数的平滑程度。最后,使用指数归一化方法计算损失函数,以避免损失值溢出。在三维点云数据集和蛋白质间相互作用数据集上的实验结果表明,在相同的训练样本和迭代次数下,自适应平滑度策略的神经架构搜索方法的分类准确率更高,性能更稳定。

关键词：正则化神经架构搜索搜索空间点云分类