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Parallel Manufacturing for Industrial Metaverses:A New Paradigm in Smart Manufacturing

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2063-2070页

作者： Jing Yang Xiaoxing Wang yandong zhao The State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Beijing SANBODY Technology Company LtdBeijing 214000China North Automatic Control Technology Institute Taiyuan 030006China

To tackle the complexity of human and social factors in manufacturing systems, parallel manufacturing for industrial metaverses is proposed as a new paradigm in smart manufacturing for effective and efficient operations of those systems, where Cyber-Physical-Social Systems(CPSSs) and the Internet of Minds(Io M) are regarded as its infrastructures and the "Artificial systems", "Computational experiments"and "Parallel execution"(ACP) method is its methodological foundation for parallel evolution, closed-loop feedback, and collaborative optimization. In parallel manufacturing, social demands are analyzed and extracted from social intelligence for product R&D and production planning, and digital workers and robotic workers perform the majority of the physical and mental work instead of human workers, contributing to the realization of low-cost, high-efficiency and zero-inventory manufacturing. A variety of advanced technologies such as Knowledge Automation(KA), blockchain, crowdsourcing and Decentralized Autonomous Organizations(DAOs) provide powerful support for the construction of parallel manufacturing, which holds the promise of breaking the constraints of resource and capacity, and the limitations of time and space. Finally, the effectiveness of parallel manufacturing is verified by taking the workflow of customized shoes as a case,especially the unmanned production line named Flex Vega.

关键词： Parallel Manufacturing Digital Workers CPSS Smart Manufacturing Industrial Metaverses

A neighborhood median weighted fuzzy c-means method for soil pore identification

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Pedosphere 2021年第5期31卷 746-760页

作者： Qiaoling Han Lei Liu yandong zhao Yue zhao School of Technology Beijing Forestry UniversityBeijing 100083(China) Beijing Laboratory of Urban and Rural Ecological Environment Beijing Municipal Education CommissionBeijing 100083(China)

Complex soil pore geometry and heterogeneity determines the ability of a soil to retain moisture and *** soil properties are widely recognized as key factors of essential ecological functions and ***,until recently,the existing pore identification methods have the problems of low identification accuracy and operating efficiency,which has restricted the development of soil *** objective of this study was to propose a neighborhood median weighted fuzzy c-means method based on grayscale-gradient feature(NMFCM-G)to identify soil pore structure automatically and *** combining three-dimensional(3 D)printing technology with X-ray computed tomography technology,a 3D simulation model with known aperture(10-cm inner diameter)was adopted to evaluate the pore identification error rate of the NMFCM-G method *** to the methods commonly applied in previous studies,the NMFCM-G method had the smallest average area relative error(2.98%),which was only 1/6 of that of the Image J method with the largest area relative error(18.46%).The NMFCM-G method also had the smallest average perimeter(5.46%),about 3/5 of that of the Image-Pro Plus method with the largest perimeter relative error(8.35%).Meanwhile,the NMFCM-G method was successfully tested on undisturbed cylindrical soil samples,providing encouraging results in terms of identifying irregular pore structure from the complex hierarchical organization of *** results show that the NMFCM-G method had the smallest distribution entropy(0.81),the smallest inter-class correlation(0.1640),and the largest distribution coefficient(0.11),which proves that the NMFCM-G method performed the best in identifying different soil pore ***,the NMFCM-G method provides new insights into identifying pore structures and thus could provide an automatic and high-efficiency technique for studying the effects of tillage and freeze-thaw cycles on pore structure and soil quality in

关键词： computed tomography grayscale-gradient feature image segmentation pore structure soil physics visualization X-ray computed tomography

Soil pore identification with the adaptive fuzzy C-means method based on computed tomography images

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Journal of Forestry Research 2019年第3期30卷 1043-1052页

作者： Yue zhao Qiaoling Han yandong zhao Jinhao Liu School of Technology Beijing Forestry University

The complex geometry and topology of soil is widely recognised as the key driver in many ecological processes. X-ray computed tomography (CT) provides insight into the internal structure of soil pores automatically and accurately. Until recently, there have not been methods to identify soil pore structures. This has restricted the development of soil science, particularly regarding pore geometry and spatial distribution. Through the adoption of the fuzzy clustering theory and the establishment of pore identification rules, a novel pore identification method is described to extract pore structures from CT soil images. The robustness of the adaptive fuzzy C-means method (AFCM), the adaptive threshold method, and Image-Pro Plus tools were compared on soil specimens under different conditions, such as frozen, saturated, and dry situations. The results demonstrate that the AFCM method is suitable for identifying pore clusters, especially tiny pores, under various soil conditions. The method would provide an optional technique for the study of soil micromorphology.

关键词： CT soil images Fuzzy C-means Fuzzy clustering theory Pore identification rule

Robust Control for Uncertain Nonlinear Feedback Systems Using Operator-based Right Coprime Factorization

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 824-829页

作者： Ni Bu Wei Chen Longguo Jin yandong zhao IEEE the College of Automation and Electronic Engineering Qingdao University of Science and Technology Haier School of Qingdao Technical College

The robust control issue for uncertain nonlinear system is discussed by using the method of right coprime factorization. As it is difficult to obtain the inverse of the right factor due to the high nonlinearity, the proving of the Bezout identity becomes troublesome. Therefore, two sufficient conditions are derived to manage this problem with the nonlinear feedback system as well as that with the uncertain nonlinear feedback system under the definition of Lipschitz norm. A simulation of temperature control is given to demonstrate the validity of the proposed method.

关键词： Bezout identity nonlinearity right coprime factorization (RCF) robust control

Feedforward and feedback optimal control for linear time-varying systems with persistent disturbances

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Journal of Systems Engineering and Electronics 2006年第2期17卷 350-354页

作者： Tang Gongyou zhao yandong Zhang Baolin Coll. of Information Science and Engineering Ocean Univ. of China Qingdao 266071 P. R. China

The optimal control problem for linear time-varying systems affected by external persistent disturbances with known dynamic characteristics but unknown initial conditions is consider and a design procedure of a feedforward and feedbaek optimal controller is presented. The condition of existence and uniqueness of the control law is given. The disturbanee observer is proposed to make the feedforward control law realizable physically. Simulation results demonstrate that the feedforward and feedbaek optimal control law is more effective and robust than the elassical state feedbaek control law with respect to external disturbanees.

关键词： time-varying systems persistent disturbances optimal control feedforward control disturbance observer.

Approximate design of optimal tracking controller for time-delay systems

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Chinese Science Bulletin 2006年第17期51卷 2158-2163页

作者： TANG Gongyou LI Chao zhao yandong College of Information Science and Engineering Ocean University of China Qingdao 266071 China

Successive approximate design of the optimal tracking controller for linear systems with time-delay is developed. By applying the successive approximation theory of differential equations, the two-point boundary value (TPBV) problem with both time-delay and time-advance terms derived from the original optimal tracking control (OTC) problem is transformed into a sequence of linear TPBV prob- lems without delay and advance terms. The solution sequence of the linear TPBV problems uniformly converges to the solution of the original OTC problem The obtained OTC law consists of analytic state feedback terms and a compensation term which is the limit of the adjoint vector sequence. The com- pensation term can be obtained from an iteration formula of adjoint vectors. By using a finite term of the adjoint vector sequence, a suboptimal tracking control law is revealed. Numerical examples show the effectiveness of the algorithm.

关键词：线性系统延时系统最佳跟踪控制逐次近似计算法 TPBV 边界值

Three-dimensional visualization of soil pore structure using computed tomography

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Journal of Forestry Research 2019年第3期30卷 1053-1061页

作者： Qiaoling Han Xibo Zhou Lei Liu yandong zhao Yue zhao School of Technology Beijing Forestry University Beijing 100083People’s Republic of China Beijing Laboratory of Urban and Rural Ecological Environment Beijing Municipal Education Commission Beijing 100083People’s Republic of China Key Lab of State Forestry Administration for Forestry Equipment and Automation School of TechnologyBeijing Forestry UniversityBeijing 10083People’s Republic of China

The geometric and spatial characteristics of pore structures determine the permeability and water retention of soils, which have important effects on soil functional diversity and ecological restoration. Until recently, there have not been tools and methods to visually and quantitatively describe the characteristics of soil pores. To solve this problem, this research reconstructs the geometry and spatial distribution of soil pores by the marching cubes method, texture mapping method and the ray casting method widely used in literature. The objectives were to explore an optimal method for three-dimensional visualization of soil pore structure by comparing the robustness of the three methods on soil CT images with single pore structure and porosity ranging from low (2–5%) to high (12–18%), and to evaluate the reconstruction performance of the three methods with different geometric features. The results demonstrate that there are aliases (jagged edges) and deficiency at the boundaries of the model reconstructed by the marching cubes method and pore volumes are smaller than the ground truth, whereas the results of the texture mapping method lack the details of pore structures. For all the soil images, the ray casting method is preferable since it better preserves the pore characteristics of the ground truth. Furthermore, the ray casting method produced the best soil pore model with higher rendering speed and lower memory consumption. Therefore, the ray casting method provides a more advanced method for visualization of pore structures and provides an optional technique for the study of the transport of moisture and the exchange of air in soil.

关键词： Soil Pore structure X-ray computed tomography Three-dimensional reconstruction Pore visualization

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基于多尺度序列特征融合的林区害虫检测算法

林业科学 2025年第2期61卷 21-30页

作者：唐延龄韩巧玲赵玥刘卫平郑一力赵燕东徐钐钐北京林业大学工学院北京100091

【目的】针对虫情测报灯采集到的林区害虫样本种类多、尺寸复杂及密集遮挡问题,提出了一种多尺度序列特征融合检测算法(MPD-YOLO),用于提升林区害虫检测的精确度,为林区害虫监测和防护提供了新的技术路径。【方法】首先,以采集于北京、... 详细信息

【目的】针对虫情测报灯采集到的林区害虫样本种类多、尺寸复杂及密集遮挡问题,提出了一种多尺度序列特征融合检测算法(MPD-YOLO),用于提升林区害虫检测的精确度,为林区害虫监测和防护提供了新的技术路径。【方法】首先,以采集于北京、河北、山西等地的林区害虫图像为基础,构建包含18类林区害虫的数据集。数据集涵盖不同场景下的害虫图像,为算法的训练与测试提供了可靠的数据支撑。其次,为提高小目标害虫的检测效果,利用3D卷积对小目标进行更为深入的尺度序列特征提取,MPD-YOLO方法引入尺度序列特征融合模块(SSFF),有效提升模型对小目标的感知能力。最后,为解决密集遮挡和多尺度害虫并存情况下的模型检测能力,MPD-YOLO方法提出了三重特征编码高效聚合模块(TFE-ELAN),通过将不同尺寸特征图进行特征融合,增强多层特征图之间信息的关联性,提升了模型的检测性能。【结果】在相同试验条件下,本研究在构建的数据集上对MPD-YOLO进行大量试验,并与主流的目标检测算法(YOLO系列、Faster-CNN等)进行对比分析。MPD-YOLO方法具有最佳的害虫识别精度,其F1-score和m AP分别达到88.43%和91.92%,比次优方法YOLOv8x分别高1.45%和1.22%。相比于原网络模型YOLOv7,MPD-YOLO的F1-score与mAP分别比YOLOv7高0.72%和2.8%,证明了本文所提方法在处理复杂目标检测任务中的优势。此外,本研究中消融试验,分析了尺度序列特征融合模块和三重特征编码高效聚合模块对整体性能的贡献,验证了各模块设计的有效性。【结论】本文提出的MPD-YOLO算法,有效提升了复杂环境下多尺度害虫的检测性能,在处理复杂环境下的检测任务时表现出较高的鲁棒性。

关键词：林区害虫防控林区生态系统小目标检测 YOLOv7 特征融合

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Optimal disturbances rejection control for singularly perturbed systems with time-delay

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High Technology Letters 2008年第1期14卷 40-44页

作者：张宝琳 Tang Gongyou zhao yandong College of Science China Jiliang University Hangzhou 310018 P.R.China College of Information Science and Engineering Ocean University of China Qingdao 266100 P.R. China College of Automatic ＆ Electronic Engineering Qingdao Universisty of Science and Technology Qingdao 266071 P. R. China

The optimal control design for singularly perturbed time-delay systems affected by external distur-bances is *** on the decomposition theory of singular perturbation,the system is decom-posed into a fast subsystem without time-delay and a slow time-delay subsystem with *** disturbances rejection control law of the slow subsystem is obtained by using the successive ap-proximation approach(SAA)and feedforward compensation ***,the feedforward and feed-back composite control(FFCC)law for the original problem is *** FFCC law consists of lin-ear analytic terms and a time-delay compensation term which is the limit of the solution sequence of theadjoint vector equations.A disturbance observer is introduced to make the FFCC law physically *** examples show that the proposed algorithm is effective.

关键词： singularly perturbed systems time-delay optimal control feedforwad control successive approximation approach (SAA) disturbances observer