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Secure Bipartite Tracking Control for Linear Leader-Following Multiagent Systems Under Denial-of-Service Attacks

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1512-1515页

作者： Lulu Chen Lei Shi Quan Zhou Hanmin Sheng Yuhua Cheng School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China china railway rolling stock corporation QINGDAO SIFANG CO.LTD.Qingdao 266311

Dear editor,This letter puts forward a secure feedback control scheme to bipartite tracking consensus for a set of generic linear autonomous agents subject to aperiodic and unknown denial-of-service(Do S)attacks.

关键词： bipartite letter autonomous

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling Lü Chunchi Zhang Dong Liang Lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of china Electronics Technology Group corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

Characteristic analysis of mechanical thermal coupling model for bearing rotor system of high-speed train

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Applied Mathematics and Mechanics(English Edition) 2022年第9期43卷 1381-1398页

作者： Yongqiang LIU Baosen WANG Shaopu YANG Yingying LIAO Tao GUO School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Traffic and Transportation Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Civil Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Tangshan Locomotive and rolling stock Co. Ltd.China Railway Rolling Stock CorporationTangshan 064000Hebei ProvinceChina

Based on Newton’s second law and the thermal network method,a mechanical thermal coupling model of the bearing rotor system of high-speed trains is established to study the interaction between the bearing vibration and *** influence of lubrication on the vibration and temperature characteristics of the system is considered in the model,and the real-time relationship between them is built up by using the transient temperature field *** considering the lubrication,the bearing outer ring vibration acceleration and node temperature considering grease are lower,which shows the necessity of adding the lubrication *** corresponding experiments for characteristics of vibration and temperature of the model are respectively *** the envelope spectrum obtained from the simulation signal and the experimental signal,the frequency values corresponding to the peaks are close to the theoretical calculation results,and the error is very *** the three stages of the temperature characteristic experiment,the node temperature change of the simulation model is consistent with the *** good agreement between simulation and experiments proves the effectiveness of the *** studying the influence of the bearing angular and fault size on the system node temperature,as well as the change law of bearing lubrication characteristics and temperature,it is found that the worse the working condition is,the higher the temperature *** the ambient temperature is low,the viscosity of grease increases,and the oil film becomes thicker,which increases the sliding probability of the rolling element,thus affecting the normal operation of the bearing,which explains the phenomenon of frequent bearing faults of high-speed trains in the low-temperature area of Northeast *** analysis shows that faults often occur in the early stage of train operation in the low-temperature environment.

关键词： high-speed train coupling dynamic model thermal network method track irregularity(TI) low temperature

Longitudinal train dynamics of electric multiple units under rescue

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Journal of Modern Transportation 2017年第4期25卷 250-260页

作者： Wei Shan Lai Wei Kai Chen Transport Bureau China Railway Corporation State Key Laboratory of Traction Power Southwest Jiaotong University CRRC Qingdao Sifang rolling stock Research Institute Co. LTD

Once operating trains are disabled on the railway lines,an efficient manner is to utilize the train for train *** to the different train and coupler types,it is difficult to formulate uniform regulations for train to train *** this paper,the longitudinal train dynamics of electric multiple units under rescue were analyzed by field and laboratory *** angling behavior of the brakinginduced coupler under compressed in-train forces was analyzed.A dynamic model for the train and draft gear system was developed considering accurate boundary limitations and braking *** safety indices and their limits for the coupled rescue train were *** evaluations of different train to train rescue scenarios were *** is indicated that the coupler vertical rotation occurs during the emergency braking applied by the assisting *** vertical force components of intrain forces lead to the carbody pitch behavior and even cause local destructions to the coupler *** carbody pitch motion can arise the inference of in-train *** on the safety evaluation of train and coupler system,the regulations for typical train to train rescue scenarios were formulated.

关键词： Electric multiple units Train rescue Coupler and draft gear Braking Coupler angling behavior

The Intelligent Beijing-Zhangjiakou High-Speed railway

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Engineering 2021年第12期7卷 1665-1672页

作者： Tongjun Wang china State railway Group corporation Limited Beijing 100844China

*** The Beijing–Zhangjiakou high-speed railway(HSR)is an important transport facility that will serve the Beijing 2022 Olympic Winter *** main line is 174 km long,and its maximum design speed is 350 km·h^(-1).It is the world’s first HSR to be designed based on the concept of an intelligent *** of the Beijing-Zhangjiakou HSR began on 29 April 2016,and the line was put into operation on 30 December 2019.

关键词： railway Beijing Speed

A novel diffusion model considering curvature radius at the bonding interface in a titanium/steel explosive clad plate

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 956-965页

作者： Hai-tao Jiang Qiang Kang Xiao-qian Yan National Engineering Research Center for Advanced rolling Technology University of Science and Technology Beijing china railway Materials Technologies Company Limited

This article introduces an element diffusion behavior model for a titanium/steel explosive clad plate characterized by a typical curved interface during the heat-treatment process. A series of heat-treatment experiments were conducted in the temperature range from 750℃ to 950℃, and the effects of heat-treatment parameters on the microstructural evolution and diffusion behavior were investigated by optical microscopy, scanning electron microscopy, X-ray diffraction analysis, and electron-probe microanalysis. Carbon atoms within the steel matrix were observed to diffuse toward the titanium matrix and to aggregate at the bonding interface at 850℃ or lower; in contrast, when the temperature exceeded 850℃, the mutual diffusion of Ti and Fe occurred, along with the diffusion of C atoms, resulting in the for- marion of Ti-Fe intermetallics （Fe2Ti/FeTi）. The diffusion distances of C, Ti, and Fe atoms increased with increasing heating temperature and/or holding time. On the basis of this diffusion behavior, a novel diffusion model was proposed. This model considers the effects of various factors, including the curvature radius of the curved interface, the diffusion coefficient, the heating temperature, and the holding rime. The experimental results show good agreement with the calculated values. The proposed model could clearly provide a general prediction of the elements＇ diffusion at both straight and curved interfaces.

关键词： explosive bonding metal cladding diffusion models interfaces heat treatment

Key Technologies and Applications of the Design and Manufacturing of Non-Circular TBMs

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Engineering 2017年第6期3卷 905-914页

作者： Jianbin Li china railway Hi-Tech Industry corporation Limited Beijing 100070 China

With the rapid development of the exploitation of underground space, more and more large- or super- large-diameter tunnel-boring machines （TBMs） are being employed to construct underground space projects. At present, because conventional circular TBMs cannot completely meet the requirements of underground space exploitation regarding the cross-section and space-utilization ratio, non-circular TBMs. which are the tunneling equipment for an ideal cross-section, have become the new market growth point. This paper first presents the technical features and development status of non-circular TBMs. Next, in reference to typical projects and technological innovation, this paper investigates key techniques including shield design optimization, multi-cutterhead excavation, special-shaped segment erection, and soil conditioning in loess strata for a rectangular pipe-jacking machine and a horseshoe-shaped TBM, in order to provide a set of feasible solutions for the design, manufacture, and construction of non-circular TBMs. Relevant engineering practice shows that non-circular TBMs with customized design and manufacture have great advantages in terms of construction schedule, settlement control, and space utilization.

关键词： Non-circular TBMs Rectangular pipe-jacking machine Horseshoe-shaped TBM Underground space exploitation

Investigation of cracking mechanism of the first tunnel lining during double-arch tunnel construction

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Underground Space 2024年第1期14卷 1-17页

作者： Yi Sui Xiaohui Cheng Zuozhou Zhao Weibin Ma railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China School of Civil Engineering Tsinghua UniversityBeijing 100084China

To solve the engineering problem of the first tunnel lining cracking caused by the second tunnel construction of double-arch highway tunnels,a research method combining distributed optical-fibre monitoring,inversion analysis and numerical simulation that can reflect lining cracking was *** fibres were laid on opposite sides of the steel arches inside the first tunnel *** optical-fibre monitoring was conducted continuously during the second tunnel *** on the fibre-optic strain profile,the lining cracking was deduced and warned in *** mechanical behaviour of the steel arch was investigated by the inversion analysis,which took into consideration the integrated impact of axial force and flexural moment.A two-dimensional(2D)load-structure method–based numerical model was established,considering the influence of different load distributions in each construction *** total strain rotating crack constitutive model was applied to reflect the cracking behaviour of concrete lining in the simulation,and the model was calibrated and verified in the *** analysis between the simulated strain distribution and the distributed optical-fibre monitoring results was carried *** deformation mode and crack distribution of the lining were *** cracking mechanism was ***,the second tunnel construction led to the loading at the top of the middle partition wall and the release of rock pressure in the first *** these load changes,the secondary lining of the first tunnel cracked on the inner side of the top of the middle partition wall owing to tension,and compression-bending failure occurred near the right arch ***,the influence of the parameters on the lining force was analysed,and a construction optimisation scheme was proposed.

关键词： Double-arch tunnel Cracking mechanism Distributed optical-fibre sensing Inversion analysis Total strain rotating crack model Loadstructure method

Efect of residual Al content on microstructure and mechanical properties of Grade B+Steel for castings for locomotives

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china Foundry 2013年第6期10卷 391-395页

作者： Wang Kaifeng Guo Erjun Cao Guojian Wang Liping Feng Yicheng Jiang Wenyong Tao Chunguo College of Materials Science and Engineering Harbin University of Science and Technology Qiqihar railway rolling stock (Group) Co. Ltd.

The bogie made of Grade B＋ steel is one of the most important parts of heavy haul trains. Some accidents were found to be the result of fracture failure of the bogies. It is very important to find the reason why the fracture failure occurred. Because AI was added for the final deoxidation during the smelting process of the Grade B＋Steel, residual AI existed to some extent in the castings. High residual AI content in the bogie casting was presumed to be the reason for the fracture. In this work, the influence of residual AI content in the range of 0.015wt.% to 0.3wt.% on the microstructure and mechanical properties of the Grade B＋ Steel was studied. The experimental results showed that when the residual AI content is between 0.02wt.% and 0.20wt.%, the mechanical properties of the steel meet the requirements of technical specification for heavy haul train parts, and the fracture is typical plastic fractures. If the residual AI content is less than 0.02wt.%, the microstructures are coarse, and the mechanical properties can not meet the demand of bogie steel castings. When the residual AI content is more than 0.2wt.%, the elongation, reduction of area, and low-temperature impact energy markedly deteriorate. The fracture mode then changes from plastic fracture to cleavage brittle fracture. Therefore, the amount of AI addition for the final deoxidation during the smelting process must be strictly controlled. The optimum addition amount needs to be controlled within the range of 0.02wt.% to 0.20wt.% for the Grade B＋Steel.

关键词： bogie Grade B+Steel AI content mechanical properties