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Control design under attacks of multi-agent switched systems via arbitrary switching

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Control design under attacks of multi-agent switched systems...

2022 Chinese Automation Congress, CAC 2022

作者： Li, Zhanjie Ma, Yajing Nanjing University of Posts and Telecommunications Institute of Advanced Technology for Carbon Neutrality Nanjing China Sichuan Xihua University Provincial Engineering Research Center for New Energy Vehicle Intelligent Control and Simulation Test Technology Chengdu China School of Internet of Things Jiangsu Key Laboratory of Broadband Wireless Communication and Internet of Things Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9781665465335

In this paper, the consensus control against attacks for a type of nonlinear multi-agent switched systems under arbitrary switching is studied. The attacks corrupt the information data, which cannot be used for the feedback design. Meanwhile, the switching logic is not allowed to be designed. To tackle the complicated effects, some intermediate variables and adaptive laws are introduced to compensate the uncertainties. By constructing a common Lyapunov function, an adaptive protocol is proposed such that the outputs of the agents achieve consensus against attacks under arbitrary switching. © 2022 IEEE.

关键词： Multi agent systems

Thermal Management of Turbine Disc Cavity System Using Ffbpnn and Nsga Ii Algorithm

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SSRN 2024年

作者： He, Zhenzong Zuo, Min Liang, Shuang Mao, Junkui College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing210016 China Collaborative Innovation Center for Advanced Aero-Engine Beijing100191 China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing211106 China

This study addresses the thermal management of the turbine disc cavity system (TDCS) by combining the feed-forward backward propagation neural network (FFBPNN) with the non-dominated sorting genetic algorithm II (NSGA II). First, the heat transfer analysis of the TDCS is carried out using the 1D fluid network method and the 2D finite element method. The impact of different cooling air inlet conditions on the heat transfer performance of the TDCS is investigated. The results show that changing the inlet pressure and temperature significantly affects the heat transfer performance of the TDCS, and the TDCS temperature field can be regulated by the inlet parameters. Then, the prediction model based on the FFBPNN is established to predict the heat transfer performance of the TDCS, and satisfactory result is obtained with mean relative error lower than 1.5% and a coefficient of determination higher than 0.998. Finally, the NSGA II is employed to optimize the cool air inlet condition to achieve thermal management of the TDCS. The Pareto solution set and the optimal solution are obtained. The results indicate that the most comprehensive improvement in the heat transfer performance of the TDCS can be achieved by the present technology. © 2024, The Authors. All rights reserved.

关键词： Temperature control

Controllable preparation and microwave absorption properties of shape anisotropic Fe_(3)O_(4) nanobelts

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Journal of Materiomics 2021年第5期7卷 957-966页

作者： Jialiang Pan Rujing Zhang Jun Ling Min Wang Zechen Li Zhen Zhen Limin He Hongwei Zhu State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China The First Scientific Research Institute of Wuxi Wuxi214035JiangsuChina Key Laboratory of Science and Technology on Advanced Corrosion and Protection for Aviation Material AECC Beijing Institute of Aeronautical MaterialsBeijing100095China

To substantially prevent electromagnetic threatens,microwave absorbing materials(MAMs)are required to eliminate surplus electromagnetic *** a typical MAM,Fe_(3)O_(4) particles with complex permittivity and permeability have been widely applied due to the coexistence of magnetic loss and dielectric ***,the necessary high mass fraction significantly limited its applications,thus Fe_(3)O_(4) nanostructures have been extensively investigated to overcome this *** this work,uniform Fe_(3)O_(4) nanobelts were prepared by electrospinning and two-step thermal *** controlling the composition and viscosity of the electrospinning precursor solution,Fe_(3)O_(4) nanobelts with tunable lateral sizes(200 nme1 mm)were *** samples with low content(only 16.7 wt%)Fe_(3)O_(4) exhibited wide maximum effective absorbing bandwidths(EAB)over 3 GHz,and Fe_(3)O_(4) nanobelts with smaller lateral sizes showed a maximum EAB of 4.93 ***,Fe_(3)O_(4) nanobelts with smaller lateral sizes presented superior reflection loss properties,the lowest reflection loss reached-53.93 dB at 10.10 GHz,while the maximum EAB was up to 2.98 *** excellent microwave reflection loss of Fe_(3)O_(4) nanobelts was contributed to the enhanced synergistic effect of magnetic loss,dielectric loss,and impedance matching,originated from the hierarchically cross-linked networks and shape *** study could broaden the practical applications of magnetic absorbers,and provided an approach for the development of shape anisotropic magnetic materials.

关键词： Fe_(3)O_(4) Nanobelts Shape anisotropy Microwave absorption Reflection loss

Synergistic Adsorption of Extracellular and Intracellular Antibiotic Resistance Genes in Struvite Crystallization by Using Simulated Swine Wastewater

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SSRN 2025年

作者： Zhang, Tianyi Liao, Wenqian Ye, Zhi-Long Huang, Xuewei Lia, Yanlin Cai, Jiasheng State Key Laboratory of Advanced Environmental Technology Institute of Urban Environment Chinese Academy of Sciences No. 1799 Jimei Road Fujian Xiamen City361021 China University of Chinese Academy of Sciences Beijing100049 China Fujian Key Laboratory of Digital Technology for Territorial Space Analysis and Simulation Xiamen361021 China LIWET Department of Green Chemistry and Technology Ghent University Campus Kortrijk Graaf Karel De Goedelaan 5 KortrijkB-8500 Belgium

Struvite recovery from livestock wastewater may pose risks of spreading antibiotic resistance genes (ARGs) into the environment. There are two forms of ARGs existed in the wastewater, i.e. intracellular ARGs (iARGs) and extracellular ARGs (eARGs), which are typically carried by plasmid and bacteria, respectively. To date, few works has been reported on the simultaneous migration behavior of iARGs and eARGs in struvite recovery. In this work, the plasmid DNA and Escherichia coli carrying tetracycline resistance genes were selected as the typical eARGs and iARGs, correspondingly, and the synergistic adsorptions of eARGs and iARGs in struvite crystallization were examined by using simulated wastewater. The adsorption capacities of eARGs and iARGs by pure struvite crystals were 9.20×106 - 8.38×1012 copies/g and 3.45×105 - 1.60×106 CFU/g, respectively. The co-existence of eARGs and iARGs would amplify eARGs adsorption, while excessive Mg2+ ion in the liquid would impair eARGs adsorption, compared to negligible impacts on iARGs adsorption. XPS analysis revealed that the predominant forces of adsorption were weaker forces, such as electrostatic or ionic hydration forces, which was ascribed to magnesium octahedral in the faces of struvite crystallite. Increasing pH values would lead to an ascent of iARGs adsorption coupled with a descent of eARGs adsorption, which was contributed to the shift of Mg density in faces of struvite crystallite and the protonation/deprotonation of eARGs molecules. These outcomes provide new understanding on eARGs and iARGs transport in phosphate recovery from wastewater. © 2025, The Authors. All rights reserved.

关键词： Escherichia coli

Conjugated Bond-Based Peridynamic Model of Laminated Composite Materials with Arbitrary Poisson's Ratio and Shear Modulus

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SSRN 2023年

作者： Liu, Shuo Che, Lu Fang, Guodong Liang, Jun Institute of Advanced Structure Technology Beijing Institute of Technology Beijing100081 China School of Civil Aviation Northwestern Polytechnical University Xi’an710072 China Yangtze River Delta Research Institute of NPU Taicang215400 China Science and Technology on Advanced Composites in Special Environments Key Laboratory Harbin Institute of Technology Harbin150001 China

The bond-based peridynamic (BB-PD) theory is inadequate in describing the four independent engineering material constants of composite lamina, which results in fixed values its Poisson’s ratios and shear moduli. This study presents a novel lamina conjugated BB-PD model encompasses not only the fiber bond and matrix bond, but also the transverse bond and conjugated bond pair. By defining these four basic PD bonds, the improved conjugated BB-PD model can overcome the restriction of material properties. The determination of the four basic PD micro-modulus parameters is achieved through the utilization of the equivalent relationship of strain energy density. In addition, the lamina conjugated BB-PD model is extended to deal with composite laminates with different stacking sequences. The present study validates the accuracy and applicability of the conjugated BB-PD model for composite materials by conducting simulations of the elastic deformation and progressive damage behavior of unidirectional laminae and laminates. Moreover, the proposed model provides an elucidation of the damage modes and failure mechanisms of laminated composite materials subjected to uniaxial loading. © 2023, The Authors. All rights reserved.

关键词： Elastic moduli

Coupling Ga(OH)3 and chromate as a universal cocatalyst for CO2 photoreduction by H2O

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Catalysis Today 2025年 458卷

作者： Xu, Xuanwen Lu, Yuehao Wang, Shuying Fan, Lele Dong, Pengyu Wang, Zheng Jiang, Ruiyu Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of Technology Yancheng224051 China School of Chemistry and Chemical Engineering Yancheng Institute of Technology Yancheng224051 China School of Mechanics and Safety Engineering Zhengzhou University 100 Kexue Road Henan Zhengzhou450001 China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China

Development of effective and universal cocatalysts are very important to the photocatalytic conversion of CO2 by H2O. Herein, CO evolution from this reaction was successfully promoted by co-catalytic coupling featuring Ga(OH)3 loading onto photocatalyst surfaces and in situ addition of Na2CrO4. This strategy exhibited excellent universality for a series of Ta- and Ga-based photocatalysts. Modifications of Ga(OH)3 created active sites for CO production on the photocatalyst surfaces. The in situ addition of Na2CrO4 improved CO evolution activity when two factors were satisfied: (1) active sites for CO evolution were created using the proper cocatalysts and (2) the photocatalyst surfaces were sufficiently quenched by hydroxide ions. © 2025 Elsevier B.V.

关键词： Photocatalytic activity

Optimal Trajectory Planning and Tracking for Autonomous Vehicles Considering Chassis Nonlinearities

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Optimal Trajectory Planning and Tracking for Autonomous Vehi...

2021 China Automation Congress, CAC 2021

作者： Zhang, Yuxiang Lyu, Jidong Wang, Jinkun Gao, Bingzhao Wang, Yuhai The State Key Laboratory of Automotive Simulation and Control Jilin University Changchun China The Advanced Technology Department of SAIC Motor Shanghai China Clean Energy Automotive Engineering Center Tongji University Shanghai China

ISBN: (纸本)9781665426473

This paper proposes a new type of local trajectory planning method for autonomous vehicles. In this frame, a lane-change or lane-keeping operation passed by the upper module is performed. Then, the trajectory planning algorithm can directly optimize the control sequences and obtain a feasible trajectory considering chassis nonlinearities and obstacles avoidance. A more accurate nonlinear model that considers the chassis' nonlinearity based on the traditional linear bicycle model is realized using a cubic polynomial of slip angle to fit the magic formula. Constraint conditions are designed based on the traffic environment to avoid obstacles. With a more precise model, the control sequences can be used as feedforward control and accompany with fine feedback control to receive a good motion control performance even in a high-speed situation. Furthermore, different time-steps of the control variables are used to reduce the number of solving variables to decrease calculation time. simulation results verify the effectiveness of the proposed method and the accuracy of the proposed nonlinear vehicle model. © 2021 IEEE

关键词： Chassis

Effect of Overlap Pattern on the Residual Stress, Surface Morphology and Fatigue Properties of Ti-6al-4v Alloy by Multiple Laser Shock Peening

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SSRN 2024年

作者： Luo, Xuekun Tian, Kai Xu, Ziheng Wang, Yiming Wang, Xin Wang, Kun Yu, Yang Guo, Lulu Ye, Chang Dang, Ning Aviation Key Laboratory of Advanced Corrosion and Protection on Aviation Materials Beijing Institute of Aeronautical Material Beijing100095 China School of Mechanical Science and Engineering Huazhong University of Science and Technology Hubei Wuhan430074 China Shenyang Engine Research Institute Shenyang110000 China State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research Institute Shaanxi Xi’an710077 China

In this study, the effects of the laser shock peening (LSP) pattern on the fatigue properties of Ti-6Al-4V alloy were investigated. The residual stress distribution and surface morphology generated by LSP were analyzed using both experiments and numerical simulations. The results show that by optimizing the LSP patterns and overlap ratios, deep compressive residual stresses and beneficial surface morphology can be obtained, resulting in a significant improvement of the fatigue performance. Specifically, LSP without optimization improves the fatigue life by a factor of 1.68 when the stress level is 550 MPa and the stress ratio is 0.1, while LSP with optimized parameters improves the fatigue life by a factor of 29.67. It has been demonstrated that the optimization of LSP patterns and overlap ratios plays an important role in enhancing the surface integrity and, thus, the fatigue performance of the Ti-6Al-4V alloy. © 2024, The Authors. All rights reserved.

关键词： Surface morphology

Susceptibility of patients with chronic obstructive pulmonary disease to heart rate difference associated with the short-term exposure to metals in ambient fine particles:A panel study in Beijing,China

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Science China(Life Sciences) 2022年第2期65卷 387-397页

作者： Ke Gao Xi Chen Xiaoying Li Hanxiyue Zhang Mengxiao Luan Yuan Yao Yifan Xu Teng Wang Yiqun Han Tao Xue Junxia Wang Mei Zheng Xinghua Qiu Tong Zhu State Key Joint Laboratory for Environmental Simulation and Pollution Control and Beijing Innovation Center for Engineering Science and Advanced Technology College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Green Research Inspection and Certification Co. Ltd.Institute of Building Research Co.Ltd.in ShenzhenShenzhen 518071China Medical Research Council Centre for Environment and HealthImperial College LondonDepartment of Epidemiology and BiostatisticsLondon W21PGUK Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China

Susceptibility of patients with chronic obstructive pulmonary disease(COPD)to cardiovascular autonomic dysfunction asso-ciated with exposure to metals in ambient fine particles(PM2.5,particulate matter with aerodynamic diameter≤2.5µm)remains poorly *** on the COPDB(COPD in Beijing)panel study,we aimed to compare the associations of heart rate(HR,an indicator of cardiovascular autonomic function)and exposure to metals in PM2.5 between 53 patients with COPD and 82 healthy controls by using linear mixed-effects *** all participants,the HR levels were significantly associated with interquartile range increases in the average concentrations of Cr,Zn,and Pb,but the strength of the associations differed by exposure time(from 1.4%for an average 9 days(d)Cr exposure to 3.5%for an average 9 d Zn exposure).HR was positively associated with the average concentrations of PM2.5 and certain metals only in patients with *** between HR and exposure to PM2.5,K,Cr,Mn,Ni,Cu,Zn,As,and Se in patients with COPD significantly differed from those in health ***,association between HR and Cr exposure was robust in COPD *** conclusion,our findings indicate that COPD could exacerbate difference in HR following exposure to metals in PM2.5.

关键词： metal in fine particles chronic obstructive pulmonary disease(COPD) susceptibility heart rate cardiovascular auto-nomic function