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Voidage correction method for DEM study of 3D pebble flows in a bed of cycloidal base

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Particuology 2024年第10期93卷 30-40页

作者： Zirui Xia Minglei Shi Quan Zou Nan Gui Xingtuan Yang Jiyuan Tu Shengyao Jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationTsinghua UniversityBeijing100084China Department of Engineering Physics Tsinghua UniversityBeijing100084China Department of automation Tsinghua UniversityBeijing100084China School of Engineering RMIT UniversityMelbourneVIC3083Australia

Voidage(porosity or void fraction)in packed particles(or pebbles)is of fundamental importance in calculating the pressure drop,obtaining the drag,predicting the bed permeability,estimating the neutron streaming,*** the case when particles are deformed,a method of voidage correction during the packing state is proposed using a discrete Element Method(DEM)simulation of 3D pebble flow inside a bed of cycloidal base.A function to evaluate the remaining volume of a pebble intercepted by horizontal and vertical planes is proposed for voidage *** that,the process of solving voidage distribution is provided in *** this method,the voidage inside the cycloidal-base pebble bed is obtained to refer to reported similar data for *** method can be potentially used for dynamical voidage calculation in CFD-DEM simulation which can get suitable voidage distribution after the correction.

关键词： Voidage Pebbleflow Packed bed discreteelementmethod Cycloidal base KD-Tree Volume correction

Guaranteed cost control of networked control systems under limited communication capacity and variable sampling

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Journal of Central South University 2014年第3期21卷 978-986页

作者：刘英英褚云凯车伟伟 School of Information Engineering Shenyang University Shenyang Institute of automation Chinese Academy of Sciences Key Laboratory of Manufacturing industrial Integrated automation Shenyang University

The problem of guaranteed cost control for the networked control systems(NCSs) with time-varying delays, time-varying sampling intervals and signals quantization was investigated, wherein the physical plant was continuous-time one, and the control input was discrete-time one. By using an input delay approach and a sector bound method, the network induced delays, quantization parameter and sampling intervals were presented in one framework in the case of the state and the control input by quantized in a logarithmic form. A novel Lyapunov function with discontinuity, which took full advantages of the NCS characteristic information, was exploited. In addition, it was shown that Lyapunov function decreased at the jump instants. Furthermore, the Leibniz-Newton formula and free-weighting matrix methods were used to obtain the guaranteed cost controller design conditions which were dependent on the NCS characteristic information. A numerical example was used to illustrate the effectiveness of the proposed methods.

关键词： networked control systems (NCSS) quantization time-varying delays time-varying sampling guaranteed cost control

Confidence-weighted mutual supervision on dual networks for unsupervised cross-modality image segmentation

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Science China(Information Sciences) 2023年第11期66卷 54-68页

作者： Yajie CHEN Xin YANG Xiang BAI School of Electronic Information and communications Huazhong University of Science and Technology School of Artificial Intelligence and automation Huazhong University of Science and Technology

The unsupervised cross-modality image segmentation has gained much attention. Many methods attempt to align different modalities via adversarial learning. Recently, self-training with pseudo labels for the unsupervised target modality has also been widely used and achieved very promising results. The pseudo labels are usually obtained by selecting reliable predictions whose highest predicted probability is larger than an empirically set value. Such pseudo label generation inevitably has noise and training a segmentation model using incorrect pseudo labels could yield nontrivial errors for the target modality. In this paper, we propose a confidence-weighted mutual supervision on dual networks for unsupervised cross-modality image segmentation. Specifically, we independently initialize two networks with the same architecture, and propose a novel confidence-weighted Dice loss to mutually supervise the two networks using their predicted results for unlabeled data. In this way, we make full use of all predictions of unlabeled images and leverage the prediction confidence to alleviate the negative impact of noisy pseudo labels. Extensive experiments on three widely-used unsupervised cross-modality image segmentation datasets(i.e., MM-WHS 2017, Brats 2018, and Multi-organ segmentation) demonstrate that the proposed method achieves superior performance to some state-of-the-art methods.

关键词： domain adaptation pseudo label mutual supervision cross-modality image segmentation

Neural Network-Based State Estimation for Nonlinear Systems With Denial-of-Service Attack Under Try-Once-Discard Protocol

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2182-2184页

作者： Xueli Wang Shangwei Zhao Ming Yang Xin Wang Xiaoming Wu the Key Laboratory of Computing Power Network and Information Security Ministry of EducationShandong Computer Science CenterQilu University of Technology(Shandong Academy of Sciences)Jinan 250014 Shandong Provincial Key Laboratory of Computer Networks Shandong Fundamental Research Center for Computer ScienceJinan 250014China Department of automation Shanghai Jiao Tong UniversityShanghai 200240China

Dear Editor,This letter deals with state estimation issues of discrete-time nonlinear systems subject to denial-of-service(DoS)attacks under the try-once-discard(TOD)*** specifically,to reduce the communication burden,a TOD protocol with novel update rules on protocol weights is designed for scheduling measurement *** addition,unknown nonlinear functions vulnerable to DoS attacks are considered due to the openness and vulnerability of the network.

关键词： Service DoS service

AIoT for Aircraft Final Assembly:An Intelligent and Collaborative Framework

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Journal of communications and Information Networks 2024年第3期9卷 262-276页

作者： Cheng Ren Xiaojing Wen Xinping Guan Cailian Chen Yehan Ma Department of automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Aircraft final assembly line(AFAL)involves thousands of processes that must be completed before ***,the heavy reliance on manual labor in most assembly processes affects the quality and prolongs the delivery *** the advent of artificial intelligence of things(AIoT)technologies has introduced advancements in certain AFAL scenarios,systematically enhancing the intelligence level of the AFAL and promoting the widespread deployment of artificial intelligence(AI)technologies remain significant *** address these challenges,we propose the intelligent and collaborative aircraft assembly(ICAA)framework,which integrates AI technologies within a cloud-edge-terminal *** ICAA framework is designed to support AI-enabled applications in the AFAL,with the goal of improving assembly efficiency at both individual and multiple process *** analyze specific demands across various assembly scenarios and introduce corresponding AI technologies to meet these *** three-tier ICAA framework consists of the assembly field,edge data platform,and assembly cloud platform,facilitating the collection of heterogeneous terminal data and the deployment of AI *** framework enhances assembly efficiency by reducing reliance on manual labor for individual processes and fostering collaboration across multiple *** provide detailed descriptions of how AI functions at each level of the ***,we apply the ICAA framework to a real AFAL,focusing explicitly on the flight control system testing *** practical implementation demonstrates the effectiveness of the framework in improving assembly efficiency and promoting the adoption of AIoT technologies.

关键词： intelligent aircraft final assembly line AIoT cloud-edge-terminal framework design

Exact Solution in the New Inflation Scenario with Induced Gravity

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communications in Theoretical Physics 2001年第10期36卷 509-512页

作者： WANG Wen-Fu Department of industrial automation Southwest Petroleum Institute Nanchong 637001 Sichuan Province China

Taking the Hubble parameter directly as a function of the scalar field instead of as a function of time,H = H( ), we present a new exact solution in the new inflation model with induced gravity. This includes solution which is inflation for end, and develops smoothly towards radiation-like evolution for ≥ end. The inflation is driven by the evolution of the field with inflation potential, V( ) = λ 2 v2)***, ns, is computed and ns lies well inside the limits set by the cosmic background explorer (COBE) *** dex of the scalar effective cosmological constant Aeff tends to zero when inflation ends.

关键词： induced gravity, new inflation, exact solution, spectral indices, effective cosmological constant

Using Entropy Based Mean Shift Filter and Modified Watershed Transform for Grain Segmentation

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International Journal of automation and computing 2015年第2期12卷 199-207页

作者： Kun Zhang Min-Rui Fei Hui-Yu Zhou Shanghai Key Laboratory of Power Station automation Technology School of Mechatronic Engineering and AutomationShanghai University The Institute of Electronics Communications and Information TechnologyQueen's University Belfast

Life science research aims to continuously improve the quality and standard of human life. One of the major challenges in this area is to maintain food safety and security. A number of image processing techniques have been used to investigate the quality of food products. In this paper, we propose a new algorithm to effectively segment connected grains so that each of them can be inspected in a later processing stage. One family of the existing segmentation methods is based on the idea of watersheding, and it has shown promising results in practice. However, due to the over-segmentation issue, this technique has experienced poor performance in various applications, such as inhomogeneous background and connected targets. To solve this problem, we present a combination of two classical techniques to handle this issue. In the first step, a mean shift filter is used to eliminate the inhomogeneous background,where entropy is used to be a converging criterion. Secondly, a color gradient algorithm is used in order to detect the most significant edges, and a marked watershed transform is applied to segment cluttered objects out of the previous processing stages. The proposed framework is capable of compromising among execution time, usability, efficiency and segmentation outcome in analyzing ring die pellets. The experimental results demonstrate that the proposed approach is effectiveness and robust.

关键词： Robust segmentation cluttered grains mean shift filter entropy modified marked watershed transform.

Flocking fragmentation formulation for a multi-robot system under multi-hop and lossy ad hoc networks

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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1057-1076页

作者： Silan LI Shengyu ZHANG Tao JIANG The Research Center of 6G Mobile communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

We investigate the impact of network topology characteristics on focking fragmentation for a multi-robot system under a multi-hop and lossy ad hoc network,including the network's hop count features and information's successful transmission probability(STP).Specifically,we first propose a distributed communication calculation execution protocol to describe the practical interaction and control process in the ad hoc network based multi-robot system,where focking control is realized by a discrete-time Olfati-Saber model incorporating STP-related ***,we develop a fragmentation prediction model(FPM)to formulate the impact of hop count features on fragmentation for specific focking *** model identifies the critical system and network features that are associated with *** considering general focking scenarios affected by both hop count features and STP,we formulate the flocking fragmentation probability(FFP)by a data fitting model based on the back propagation neural network,whose input is extracted from the *** FFP formulation quantifies the impact of key network topology characteristics on fragmentation *** results verify the effectiveness and accuracy of the proposed prediction model and FFP formulation,and several guidelines for constructing the multi-robot ad hoc network are concluded.

关键词： Multi-robot flocking Flocking fragmentation probability Fragmentation prediction Multi-robot communication networks

Event-triggered impulsive synchronization of heterogeneous neural networks

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Science China(Information Sciences) 2024年第2期67卷 331-332页

作者： Zhengxin WANG Chongfang JIN Wangli HE Min XIAO Guo-Ping JIANG Jinde CAO College of Science Nanjing University of Posts and Telecommunications Jiangsu Engineering Lab for IOT Intelligent Robots (IOTRobot) Nanjing University of Posts and Telecommunications Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and Technology School of automation Nanjing University of Posts and Telecommunications School of Mathematics Southeast University Yonsei Frontier Lab Yonsei University

Synchronization is one of the most important dynamics in neural networks. Several scholars have studied the quasi-synchronization of heterogeneous neural networks [1],wherein external controllers play a significant role. Impulsive control, a kind of energy-saving control, is activated instantaneously only at specific discrete moments.

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