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30th International Conference on Mechatronics and Machine Vision in Practice, M2VIP 2024

作者： Lyu, Xiaofan Wang, Pingjiang Gao, Chaoyang Zhao, Donglin Wei, Peng Luo, Wenbin Huazhong University of Science and Technology School of Mechanical Science and Engineering Wuhan China Quanzhou Hust Research Institute of Intelligent Manufacturing QuanZhou China Huazhong University of Science and Technology National Numerical Control System Engineering Research Center Wuhan China

ISBN: (纸本)9798350391916

Aiming at the flexibility and reconfigurability needs for fatigue test applications, the demand for a PLCopen-based development framework arises. In this study, we utilize the IEC 61131-3 programmable language and PLCopen specifications to design the controller for electro-hydraulic servo loading system. Firstly, PLCopen group function block diagrams are proposed in accordance with experiments. Multiple groups can manage different experiments simultaneously. Then, PLCopen channel function block diagrams are designed to manage district channels in a group. To correct tracking errors, each channel incorporates a peak-valley phase compensator. Peak-valley phase compensator could potentially be used to adjust for multi-frequency sinusoidal spectrum. Finally, simulation and experiment results verify that tracking error could be kept within a defined neighbourhood region. © 2024 IEEE.

关键词： Fatigue testing

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Analysis and modeling of the thermal errors of carriage system of a precision machine tool driven by linear motor

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Key engineering Materials 2014年 579-580卷 645-653页

作者： Yuan, Shuai Peng, Fangyu Zhou, Lin Yao, Peifeng National Numerical Control System Engineering Research Center Huazhong University of Science and Technology Wuhan 430074 China

ISBN: (纸本)9783037858271

The drive system with linear motor of precision machine tools can generate a lot of heat and part of it is conducted to machine tools structures. Therefore, it can lead to the thermal deformation of the structures and hence seriously influences the processing accuracy. In this paper, the finite element model (FEM) considering convection of the planes, the pipelines of the cooler system and thermal resistance is adopted to investigate the thermal distribution and thermal deformation of the carriage system of precision machine tools driven by linear motor. In addition, position-independent thermal errors models of the carriage system are proposed for the main heat source, the primary part of the linear motor, of the carriage system travels with the worktable;the feature genetic algorithm is used to procure the thermal key points of the carriage due to the great number of candidate points. At last, the experiment is conducted on the Y-axis carriage system of precision three-axis machine tool, which demonstrates the two geometric errors δx and Εz caused by the thermal deformation are significantly tiny. The mathematical models of three thermal errors are obtained through the temperatures of the key thermal points because the interferometer cannot measure the roll error Εy. Also, the comparison between the measurements and the thermal errors models indicates that the position-independent thermal models are capable of satisfactorily predicting the magnitude of the other three geometric errors of the carriage system caused by the thermal deformation and also being used in further study of compensation system.

关键词： Genetic algorithms

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Aqueous production of sulfur-containing aerosols from nitroaromatic compounds and SO2 in wintertime urban haze

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Science Bulletin 2025年

作者： Yang, Ning Wang, Junfeng Jacob, Daniel J. Ye, Jianhuai Sheng, Ming Niu, Mutong Qin, Yiming Ge, Xinlei Sun, Yele Wang, Zifa Wang, Yuhang Wu, Fengchang Liu, Cong-Qiang George, Christian Fu, Pingqing Institute of Surface-Earth System Science School of Earth System Science Tianjin University Tianjin300072 China School of Emergency Management Nanjing University of Information Science and Technology Nanjing210044 China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing210044 China John A. Paulson School of Engineering and Applied Sciences Harvard University CambridgeMA02138 United States School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen518055 China School of Energy and Environment City University of Hong Kong Hong Kong999077 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing100029 China School of Earth and Atmospheric Sciences Georgia Institute of Technology AtlantaGA02115 United States State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing100012 China Université Claude Bernard Lyon 1 CNRS IRCELYON VilleurbanneF-69626 France

Nighttime aqueous oxidation of fossil fuel emissions is a significant source of atmospheric secondary organic aerosols. However, the underlying mechanism of the aqueous processing remains unclear. Utilizing ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry of water-soluble organic carbon samples, we present field observations that reveal the aqueous-phase conversion of nitroaromatic compounds (NACs) and sulfur-containing aerosols from fossil fuel combustion at high relative humidity during a severe haze event in Beijing in the winter of 2016. We have confirmed that the ring-breaking oxidation of NACs can generate nitrous acid in the aqueous phase, which rapidly oxidizes sulfur dioxide (SO2) to sulfate. Subsequently, reactions between sulfate and unsaturated compounds contribute to the formation of aliphatic organosulfates. Our results elucidate a molecular-level understanding of the aqueous production of sulfur-containing aerosols from NACs and SO2 in wintertime urban haze. © 2025 Science China Press

关键词： Sulfur dioxide

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Drought frequency, intensity, and exposure have increased due to historical land use and land cover changes

Communications Earth & Environment

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Communications Earth & Environment 2025年第1期6卷 1-13页

作者： Tao Tang Lin Wang Junji Cao Jun Ge Haiyun Shi Xuhui Lee State Key Laboratory of Earth System Numerical Modeling and Application Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Science Center for Earth System Numerical Simulation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric Sciences Nanjing University Nanjing China School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen China School of the Environment Yale University New Haven CT USA

Drought, a marked deficiency of surface water, has a wide adverse impact on the environment, agriculture, and the socio-economy. The global impact of land use changes on drought features and associated exposures to droughts, however, remains largely unknown. In this study, the changes of drought features are estimated by using the model simulations with and without land use change. We show that historical land use changes since 1850, mainly deforestation and crop expansion, has increased the drought frequency, duration, and severity over half of the global land area. Regions with greater activity tend to experience stronger exacerbation of drought events. Owing to their increasing frequency and prolonged duration, populations, croplands and forests are increasingly exposed to drought events, which poses serious potential impacts on human health, agriculture, and forest ecosystems. The enhanced drought events could be substantially alleviated by potential reforestation activity. Our results provide useful information for land-management-related policy-making.

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Model-based test case generation for function testing of CTCS-3 onboard subsystem

International Journal of Control and Automation

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International Journal of control and Automation 2015年第10期8卷 171-178页

作者： Lv, Jidong Ren, Pengcheng Lei, Chen Li, Kaicheng Tang, Tao National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China State1 Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China School Of Electronics Electrical and Computer Engineering The University of Birmingham Birmingham United Kingdom

The CTCS-3(Chinese Train control system level 3) is an automatic system which is an integrated of advanced control technology, advanced communication technology, advanced computer technology and railway signal technology. It plays an important role in assuring safety and improving efficiency in railway. As a core subsystem in CTCS-3, the onboard subsystem is a typical safety-critical system, in which any fault can lead to huge human injury or wealth losing. Function testing method which is mainly focus on the conformance relation between the specification and the system Under Test (SUT) has been widely used in testing onboard subsystem in the past few years. However, most of the test cases are manually generated which can 1 be reused and leads to repeated works when the specification is changed. To improve the testing efficiency and quality, model-based testing method is introduced. We use a tool chain to generate test case automatically based on Timed Automata theory and then apply in function testing of onboard subsystem. Firstly, we establish the scenario-tree by analyzing the specification of onboard subsystem and Vital Computer and Environment (V-E) timed automata network model of mode transition using tool Uppaal. Then, according to the relation between train modes and operational scenarios, test cases are automatically generated by tool CoVer with definition coverage criteria based on the Observer Automata theory. Finally, a selection algorithm is given to choose a complete test sequence from the test cases. Different test suitss of onboard subsystem are acquired and compared with different coverage criteria and coverage items. A complete model transition function test suits are derived which is proven very useful for testing the onboard subsystem. © 2015 SERSC.

关键词： Specifications

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A Modular numerical control system Based on Embedded Technology

A Modular Numerical Control System Based on Embedded Technol...

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International Conference on Computational Intelligence and Software engineering (CiSE)

作者： Zhengyi Li Xiaoqi Tang Xiangdong Zhou State Engineering Research Center of Numerical Control System School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China

This paper proposes a novel architecture of the numerical control (NC) system based on multiprocessor and real-time Ethernet. To comply with the trend of modular, open framework NC system, the hardware architecture is composed of ARM, DSP and FPGA modules, of which the ARM module is responsible for HMI (human-machine interface), the DSP module is in charge of core calculation, and the FPGA module plays the role of logical operation and constructs a real-time Ethernet for integrating servo drive modules, machine input/output units into the system. The proposed NC system has the advantages of smart reconfiguration, high performance but low cost. Finally, successful utilization of this system for a hoop bending machine control is briefly described.

关键词： Computer numerical control Real time systems Ethernet networks Digital signal processing Field programmable gate arrays Hardware Man machine systems Servomechanisms Costs Machine control

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Two-Stage Robust Optimization Under Decision Dependent Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2022年第7期9卷 1295-1306页

作者： Yunfan Zhang Feng Liu Yifan Su Yue Chen Zhaojian Wang João P.S.Catalão State Key Laboratory of Power System and Generation Equipment the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Automation Engineering the Chinese University of Hong KongHong Kong SARChina Ministry of Education Key Laboratory of System Control and Information Processing the Department of AutomationShanghai Jiao Tong Universityand also with Shanghai Engineering Research Center of Intelligent Control and ManagementShanghai 200240China Faculty of Engineering of the University of Porto and Institute for Systems and Computer Engineering Technology and Science(INESC TEC)Porto 4200-465Portugal IEEE

In the conventional robust optimization(RO)context,the uncertainty is regarded as residing in a predetermined and fixed uncertainty *** many applications,however,uncertainties are affected by decisions,making the current RO framework *** paper investigates a class of two-stage RO problems that involve decision-dependent *** introduce a class of polyhedral uncertainty sets whose right-hand-side vector has a dependency on the here-and-now decisions and seek to derive the exact optimal wait-and-see decisions for the second-stage problem.A novel iterative algorithm based on the Benders dual decomposition is proposed where advanced optimality cuts and feasibility cuts are designed to incorporate the uncertainty-decision *** computational tractability,robust feasibility and optimality,and convergence performance of the proposed algorithm are guaranteed with theoretical *** motivating application examples that feature the decision-dependent uncertainties are ***,the proposed solution methodology is verified by conducting case studies on the pre-disaster highway investment problem.

关键词： Benders decomposition decision-dependent uncertainty endogenous uncertainty robust optimization(RO)

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Effects and mechanisms of the main longitudinal beam shape on vortex-induced vibrations of Π-shaped composite girders

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Structures 2025年 78卷

作者： Kaiwen Li Yifei Sun Qingkuan Liu Yangxue Wang Qingcai Wang Binxuan Wang School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China Key Laboratory of Roads and Railway Engineering Safety Control Ministry of Education Shijiazhuang 050043 China Innovation Center for Wind Engineering and Wind Energy Technology of Hebei Province Shijiazhuang 050043 China Research Center for Wind Engineering and Engineering Vibration Guangzhou University Guangzhou 510006 China

As a typical blunt body cross-section, Π-shaped composite girders are notably susceptible to vortex-induced vibrations (VIVs). Therefore, it is crucial to investigate their VIV characteristics and develop corresponding aerodynamic countermeasures. In the present study, synchronous pressure and vibration measurements, combined with computational fluid dynamics (CFD) simulations, were conducted for various Π-shaped composite girder models with different main longitudinal beam shapes. The effects of the main longitudinal beam height ( h ), bottom plate width ( b ), and bottom plate inclination angle ( β ) on the vertical VIV were systematically investigated. The underlying mechanisms of VIV for these parameters were discussed by analyzing the time-frequency characteristics of aerodynamic forces, the relationship between local lift forces and vortex-excited forces (VEFs), and flow field characteristics. The results indicate that reducing h , increasing b , or setting β to 20° can suppress vertical VIV, but the suppressive effect varies and is related to the wind attack angle. From the perspective of the flow field, the formation and movement of the large separation vortices at the leading edge of the girder are responsible for the observed vertical VIVs. The aforementioned parameter adjustments that exhibit an excellent VIV suppression effect can reduce the size and suppress the development of the leading-edge vortices, thereby improving the stability of the flow field. From the perspective of aerodynamic force characteristics, these adjustments can reduce the RMS value of the surface pressure coefficient. They can also shift the dominant frequency of the pressure spectrum away from the vibration frequency, weaken the dominant role of the vibration frequency in the overall lift, and greatly reduce the contribution of local lift to the overall vortex-excited forces (VEFs). As a result, VIV is suppressed.

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Data-driven technology of fault diagnosis in railway point machines:review and challenges

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Transportation Safety and Environment 2022年第4期4卷 19-32页

作者： Xiaoxi Hu Yuan Cao Tao Tang Yongkui Sun State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China National Engineering Research Center of Rail Transportation Operation Control System Beijing Jiaotong UniversityBeijing 100044China.

Safety and reliability are absolutely vital for sophisticated Railway Point Machines(RPMs).Hence,various kinds of sensors and transducers are deployed on RPMs as much as possible to monitor their behaviour for detection of incipient faults and anticipation using data-driven *** paper firstly analyses and summarizes six RPMs’characteristics and then reviews the data-driven algorithms applied to fault diagnosis in RPMs during the past *** provides not only the process and evaluation metrics but also the pros and cons of these different ***,regarding the characteristics of RPMs and the existing studies,eight challenging problems and promising research directions are pointed out.

关键词： Railway point machine(RPM) fault diagnosis data-driven technology condition monitoring

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High-precision measurement of defocus amount for laser welding by analyzing image definition

High-precision measurement of defocus amount for laser weldi...

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International Conference on control, Automation and Robotics (ICCAR)

作者： WenJun Shao Gen Li ShiHua Gong Yu Huang PingJia Jia National Numerical Control System Engineering Research Center Huazhong University of Science and Technology Wuhan China

The defocus amount is of great importance to laser welding quality of tight butt joint formed by two sheet metal according to laser welding process. A high-precision measurement system mainly consists of microscopic enlarger lens, CCD camera and LED light source is presented in this article. This measure system which is based on the principle of depth from focus can ensure an accurate defocus amount in tight butt joint welding. The depth position of the weld seam in the optical axis direction is measured by analyzing image definition of the weld seam micrograph. Measurement range and precision of the seam centerline in depth direction are ±0.45mm and ±10μm respectively.

关键词： Welding Optical imaging Optical variables measurement Cameras Robot sensing systems Position measurement Measurement uncertainty

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