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Science China(Information Sciences) 2024年第1期67卷 312-313页

作者： Huan LIU Qiyu YANG Chengji JIN Jiajia CHEN Lulu CHOU Xiao YU Yan LIU Genquan HAN Research center for intelligent Chips School of Microelectronics Xidian University

The steep subthreshold swing (SS) could be achieved in negative capacitance field-effect transistors (NCFET) to reduce power dissipation in modern electronics. Polycrystalline Hf O2-based ferroelectric materials have attracted great interest due to their better thickness scalability and CMOS process compatibility [1].

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Optimal coordination of zero carbon building energy systems

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National Science Open 2024年第3期3卷 13-28页

作者： Wangyi Guo Zhanbo Xu Jinhui Liu Yaping Liu Jiang Wu Kun Liu Xiaohong Guan School of Future Technology Xi'an Jiaotong University Ministry of Education Key Lab for intelligent Networks and Network Security School of Automation Science and EngineeringXi'an Jiaotong University center for intelligent and networked systems Department of AutomationTNLISTTsinghua University

Optimal scheduling of renewable energy sources and building energy systems serves as a pivotal strategy for achieving zero carbon emission.However,the coordination of zero carbon building energy systems(ZCBS) is still challenging due to the complicated interactions among multi-energy hybrid storage and the complex coordination between seasonal and daily scheduling.Therefore,this study develops a coordination scheduling approach for ZCBS.An operation model and a seasonal-daily scheduling approach are developed to optimize the operation of hydrogen,geothermal,and water storage devices.The performance of the developed method is demonstrated using numerical case studies.The results show that the ZCBS can be achieved by using renewable energy sources with the system flexibility provided by hydrogen,geothermal,and water storage devices.It is also found that the developed scheduling approach reduces operation costs by more than 43.4%under the same device capacity,compared with existing scheduling approaches.

关键词： zero carbon building energy systems seasonal-daily scheduling multi-energy storage two-stage robust optimization

Resilient sliding mode control for 2D CPSs under denial-of-service attacks

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Science China(Information Sciences) 2024年第6期67卷 262-278页

作者： Lingling LI Rongni YANG Zhiguang FENG Ligang WU College of intelligent systems Science and Engineering Harbin Engineering University School of Control Science and Engineering Shandong University School of Astronautics Harbin Institute of Technology

This study addresses the resilient sliding mode control(SMC) problem for two-dimensional cyber-physical systems(2D CPSs) characterized by the Roesser model under denial-of-service attack(DoSA), which can interfere with signal transmission over the communication network. First, the DoS-A model is established by introducing constraints on the Do S frequency and duration. Then, based on active or silent attack situations, the considered system is described as a switched mode. Furthermore, together with Lyapunov theory, the average dwell time technique is employed to deduce sufficient criteria that assure the existence of the desired sliding mode controller. Finally, verification examples are provided to show the validity of the established SMC scheme.

关键词： two-dimensional systems cyber-physical systems denial-of-service attack resilient sliding mode control

D-scheduler:A scheduler in time-triggered distributed system through decoupling dependencies between tasks and messages

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Science China(Technological Sciences) 2024年第1期67卷 183-196页

作者： YANG TingTing ZHANG YuQi YUE FengLai WUNIRI QiQiGe TONG Chao School of Computer Science&Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Virtual Reality Technology and systems Beihang UniversityBeijing 100191China National Innovation center of intelligent and Connected Vehicles Beijing 100176China

Time-triggered architecture,as a mainstream design of the distributed real-time system,has been successfully applied in the aerospace,automotive and mechanical industries.However,time-triggered scheduling is a challenging NP-hard problem.There are few studies that could quickly solve the scheduling problem of large distributed time-triggered systems.To solve this problem,a communication affinity parameter is defined in this paper to describe the degree of bias of the shaper task towards sending or receiving messages.Based on this,an innovative task-message decoupling model named D-scheduler is built to reduce the computation complexity of the scheduling problem in large-scale systems.Additionally,we provide mathematical proof that our model is a convex optimization that is easy to solve with existing computational tools.Our experiments substantiate the efficacy of the D-scheduler.It dramatically reduces the scheduling complexity of large-scale real-time systems with a small loss of solving space compared to the federal scheduler.

关键词： time-triggered architecture time-triggered scheduling communication affinity parameter task-message decoupling model

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Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research(International) 2024年第3期31卷 688-699页

作者： Wen-quan Sun Sheng-yi Yong Tie-heng Yuan Ting-song Yang An-rui He Chao Liu Rui-chun Guo National Engineering Research center for Advanced Rolling and intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation process.Given the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was investigated.To quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was established.Based on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental validation.The thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under stress.Subsequently,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 steel.The results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite transformation.Furthermore,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： Liang LU Zhongdong LIANG Yuming LIU Zhipeng WANG Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science center for intelligent Autonomous systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking conditions.Through a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these valves.The analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid structure.Variations in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow properties.This study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet valves.More specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking phenomenon.In contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking

Collective Movement Simulation:Methods and Applications

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Machine Intelligence Research 2024年第3期21卷 452-480页

作者： Hua Wang Xing-Yu Guo Hao Tao Ming-Liang Xu School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou450001China Engineering Research center of intelligent Swarm systems Ministry of EducationZhengzhou450001China National Supercomputing center in Zhengzhou Zhengzhou450001China China Ship Development and Design center Wuhan430060China

Collective movement simulations are challenging and important in many areas,including life science,mathematics,physics,information science and public safety.In this survey,we provide a comprehensive review of the state-of-the-art techniques for collective movement simulations.We start with a discussion on certain concepts to help beginners understand it more systematically.Then,we analyze the intelligence among different collective objects and the emphasis in different fields.Next,we classify existing collective movement simulation methods into four categories according to their effects,namely versatility,accuracy,dynamic adaptability,and assessment feedback capability.Furthermore,we introduce five applications of layout optimization,emergency control,dispatching,unmanned systems,and other derivative applications.Finally,we summarize possible future research directions.

关键词： Collective movement simulation multiple objects multiple discipline simulation effect collective intelligence

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of networked Control systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis method.However,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational effort.Additionally,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different moments.Thus,there is heterogeneity in field data,which can dramatically impair the diagnostic accuracy.To solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this paper.First,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC data.Subsequently,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data heterogeneity.Finally,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the 4S-TFSM.Experiments on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational cost.To the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

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Plotinus:A Satellite Internet Digital Twin System

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Journal of Communications and Information Networks 2024年第1期9卷 24-33页

作者： Yue Gao Kun Qiu Zhe Chen Wenjun Zhu Qi Zhang Handong Luo Quanwei Lin Ziheng Yang Wenhao Liu The intelligent Networking and Computing Research center and School of Computer Science Fudan UniversityShanghai 200433China

The development of space-air-ground integrated networks (SAGIN) requires sophisticated satellite Internet emulation tools that can handle complex, dynamic topologies and offer in-depth analysis. Existing emulation platforms struggle with challenges like the need for detailed implementation across all network layers, real-time response, and scalability. This paper proposes a digital twin system based on microservices for satellite Internet emulation,namely Plotinus,which aims to solve these problems. Plotinus features a modular design, allowing for easy replacement of the physical layer to emulate different aerial vehicles and analyze channel interference. It also enables replacing of path computation methods to simplify testing and deploying algorithms. In particular, Plotinus allows for real-time emulation with live network traffic,enhancing practical network models. The evaluation result shows Plotinus’s effective emulation of dynamic satellite networks with real-world devices. Its adaptability for various communication models and algorithm testing highlights Plotinus’s role as a vital tool for developing and analyzing SAGIN systems, offering a cross-layer,real-time,and scalable digital twin system.

关键词： network emulation framework dynamic topology adjustment microservice architecture

Low-Rank Optimal Transport for Robust Domain Adaptation

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1667-1680页

作者： Bingrong Xu Jianhua Yin Cheng Lian Yixin Su Zhigang Zeng IEEE the School of Automation Wuhan University of TechnologyWuhan 430070China intelligent Transportation systems Research center Wuhan University of TechnologyWuhan 430063 Chongqing Research Institute Wuhan University of TechnologyChongqingChina the School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 the Key Laboratory of Image Processing and intelligent Control of Education Ministry of China Wuhan 430074China

When encountering the distribution shift between the source(training) and target(test) domains, domain adaptation attempts to adjust the classifiers to be capable of dealing with different domains. Previous domain adaptation research has achieved a lot of success both in theory and practice under the assumption that all the examples in the source domain are welllabeled and of high quality. However, the methods consistently lose robustness in noisy settings where data from the source domain have corrupted labels or features which is common in reality. Therefore, robust domain adaptation has been introduced to deal with such problems. In this paper, we attempt to solve two interrelated problems with robust domain adaptation:distribution shift across domains and sample noises of the source domain. To disentangle these challenges, an optimal transport approach with low-rank constraints is applied to guide the domain adaptation model training process to avoid noisy information influence. For the domain shift problem, the optimal transport mechanism can learn the joint data representations between the source and target domains using a measurement of discrepancy and preserve the discriminative information. The rank constraint on the transport matrix can help recover the corrupted subspace structures and eliminate the noise to some extent when dealing with corrupted source data. The solution to this relaxed and regularized optimal transport framework is a convex optimization problem that can be solved using the Augmented Lagrange Multiplier method, whose convergence can be mathematically proved. The effectiveness of the proposed method is evaluated through extensive experiments on both synthetic and real-world datasets.

关键词： Domain adaptation low-rank constraint noise corruption optimal transport

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