检索结果-内蒙古大学图书馆

Ultra Reliable Load-Aware Connection Management(LACM)Algorithm in WIA-FA Systems

China Communications 2024年第8期21卷 142-161页

作者： Liu Gang Jiang Chunhao Ren Xiaochun Fan Pingzhi Liang Chengchao Ma Zheng Southwest Jiaotong University Chengdu 611756China State Key Laboratory of Rail Transit Engineering Informatization(FSDI) Xi’an 710043China Chongqing University of Posts and Telecommunications Chongqing 400065China

The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication *** an international standard based on 802.11,Wireless networks for Industrial Automation-Factory Automation(WIA-FA)greatly improves the reliability in factory automation scenarios by Time Division Multiple Access(TDMA).However,in ultra-dense WIA-FA networks with mobile users,the basic connection management mechanism is *** of the handover and resource management algorithms are all based on frequency division multiplexing,not suitable for the TDMA in the WIA-FA ***,we propose Load-aware Connection Management(LACM)algorithm to adjust the linkage and balance the load of access devices to avoid blocking and improve the reliability of the *** then we simulate the algorithm to find the optimal settings of the *** comparing with other existing algorithms,the result of the simulation proves that LACM is more efficient in reliability and maintains high reliability of more than 99.8%even in the ultra-dense moving scenario with 1500 field ***,this algorithm ensures that only a few signaling exchanges are required to ensure load bal-ancing,which is no more than 5 times,and less than half of the best state-of-the-art algorithm.

关键词： connection management load-aware multi-connectivity reliability retransmission WIAFA

来源：评论

学校读者我要写书评

暂无评论

Three-dimensional hydro-mechanical coupling numerical simulation of shield-driven cross-river twin tunnels:A case study

引用

Underground Space 2024年第3期16卷 106-125页

作者： Chengwen Wang Xiaoli Liu Danqing Song Enzhi Wang Guohui Yan Ran Zhou Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China YSD Rail Transit Construction Company Limited Guangzhou 510630China

With the rapid development of urban underground space,the construction of shield-driven cross-river twin tunnels is increasing,and the complex hydro-mechanical coupling effects and twin-tunnel interactions bring huge construction risks to such projects,which have attracted more and more *** study aims to understand the excavation effects induced by shield driving of cross-river twin tunnels through numerical simulation.A refined three-dimensional numerical model based on the fully coupled hydro-mechanical theory is *** model considers the main components of the slurry pressure balance shield(SPBS)machine,including support force,jacking thrust,grouting pressure,shield-rock interaction and lining-grouting interaction,as well as the detailed construction *** purpose is to examine the excavation effects during construction,including rock deformation around tunnels,the change in pore pressure,and the response of the *** results show the influence range of twin-tunnel excavation on rock deformation and pore pressure,as well as the modes of lining *** addition,this study also systematically investigates the effects of water level fluctuation and burial depth on twin-tunnel *** results indicate that the increase of water level or burial depth will enhance the excavation effects and strengthen the twin-tunnel *** results provide useful insights for estimating the construction impact range and degree of twin tunnels,and serve as basic references for the design of cross-river twin tunnels.

关键词： Numerical modeling Twin tunnels Crossing river Hydro-mechanical coupling Lining response

来源：评论

学校读者我要写书评

暂无评论

On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/rail Flexibility and Its Mitigation Measures

引用

Chinese Journal of Mechanical engineering 2024年第1期37卷 40-61页

作者： Yunfan Yang Feifan Chai Pengfei Liu Liang Ling Kaiyun Wang Wanming Zhai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway *** present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external *** this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is ***,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are *** results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and *** of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal *** research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

关键词： Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures

来源：评论

学校读者我要写书评

暂无评论

An Intelligent Optimization Method of Reinforcing Bar Cutting for Construction Site

引用

Computer Modeling in engineering & Sciences 2023年第1期134卷 637-655页

作者： Zhaoxi Ma Qin Zhao Tianyou Cang Zongjian Li Yiyun Zhu Xinhong Hei Department of Civil Engineering and Architecture Xi’an University of TechnologyXi’an710048China State Key Laboratory of Rail Transit Engineering Informatization(FSDI) Xi’an710043China Department of Computer Science and Engineering Xi’an University of TechnologyXi’an710048China

To meet the requirements of specifications,intelligent optimization of steel bar blanking can improve resource utilization and promote the intelligent development of sustainable *** one of the most important building materials in construction engineering,reinforcing bars(rebar)account for more than 30%of the cost in civil engineering.A significant amount of cutting waste is generated during the construction *** cutting waste increases construction costs and generates a considerable amount of CO_(2)*** study aimed to develop an optimization algorithm for steel bar blanking that can be used in the intelligent optimization of steel bar engineering to realize sustainable *** the proposed algorithm,the integer linear programming algorithm was applied to solve the *** was combined with the statistical method,a greedy strategy was introduced,and a method for determining the dynamic critical threshold was developed to ensure the accuracy of large-scale data *** proposed algorithm was verified through a case study;the results confirmed that the rebar loss rate of the proposed method was reduced by 9.124%compared with that of traditional distributed processing of steel bars,reducing CO_(2)emissions and saving construction *** the scale of a project increases,the calculation quality of the optimization algorithmfor steel bar blanking proposed also increases,while maintaining high calculation *** the results of this study are applied in practice,they can be used as a sustainable foundation for building informatization and intelligent development.

关键词： Building construction rebar work cutting stock problem optimization algorithm integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Blackening failure of poly-α-olefin impregnated porous polymide due to the splitting of lubrication oil catalyzed by iron

引用

Friction 2024年第9期12卷 1969-1979页

作者： Pengfei SHI Yang YIN Shaohua ZHANG Diankai ZHANG Yuanyuan JIANG Yang WANG Ningning ZHOU Tao QING Jintao WU Linmao QIAN Jiyang ZHANG Lei CHEN Tribology Research Institute State Key Laboratory of Rail Transit Vehicle SystemSchool of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100094China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Lubrication failure accompanying with blackening phenomenon significantly reduces the long-running operational reliability of porous polymide(PPI)lubricated with poly-α-olefin(PAO)***,the effects of lubrication condition and counter-surface chemistry on the blackening failure of PAO impregnated PPI were studied through the comparison of the tribological tests against GCr15 steel ball and Al_(2)O_(3)ceramic ball with and without PAO oil *** products were found to be formed on the PAO impregnated PPI surface slid against steel ball or Al_(2)O_(3)ball added with iron nano-particles,but be absent under the conditions without iron or PAO *** analysis indicated that the iron-catalyzed splitting of PAO oil into small molecule alkanes and following the formation of black organic matter should be mainly responsible for the blackening *** dynamic(MD)simulations demonstrated that the iron facilitated the separation of hydrogen atom and the following broken of C–C bonds in PAO molecules,final resulting in the splitting of PAO oil.

关键词： porous polyimide poly-α-olefin oil friction-induced blackening phenomenon tribological performance ReaxFF MD simulation

来源：评论

学校读者我要写书评

暂无评论

Comparative study on vibro-acoustic properties of sandwich shells containing functionally-graded porous materials in a thermal environment

引用

Applied Mathematics and Mechanics(English Edition) 2025年第5期46卷 947-964页

作者： Xinbiao XIAO Xinte WANG Jian HAN Yuanpeng HE State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 611756China School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 611756China

The dynamics of functionally-graded(FG) sandwich shells with varied pore distributions in thermal environments is investigated,focusing on their free vibration behaviors and sound transmission loss(STL) *** effective material parameters are calculated by integrating the graded distribution through three distinct pore distribution *** dynamic governing equations are derived by means of the first-order shear deformation theory,guided by Hamilton's *** solutions for the natural frequency and acoustic transmission loss factor are obtained from the shell's free vibration general solution and the acoustic displacement function,respectively.A detailed numerical analysis is conducted to assess the impacts of the structural and geometric parameters,as well as the ambient temperature,on the vibro-acoustic *** results indicate that vibro-acoustic coupling is most significant in shells with a symmetric non-uniform pore distribution,and the resonance frequency shifts towards lower frequencies as the power-law index *** findings offer valuable insights for enhancing the design of materials aimed at vibration damping and acoustic management.

关键词： functionally-graded(FG)porous material cylindrical shell thermal environment sound transmission loss(STL) vibro-acoustic coupling

来源：评论

学校读者我要写书评

暂无评论

Numerical Study on Reduction in Aerodynamic Drag and Noise of High-Speed Pantograph

引用

Computer Modeling in engineering & Sciences 2024年第5期139卷 2155-2173页

作者： Deng Qin Xing Du Tian Li Jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China School of Electrical Engineering Southwest Jiaotong UniversityChengdu610031China

Reducing the aerodynamic drag and noise levels of high-speed pantographs is important for promoting environmentally friendly,energy efficient and rapid advances in train *** computational fluid dynamics theory and the K-FWH acoustic equation,a numerical simulation is conducted to investigate the aerodynamic characteristics of high-speed pantographs.A component optimization method is proposed as a possible solution to the problemof aerodynamic drag and noise in high-speed *** results of the study indicate that the panhead,base and insulator are the main contributors to aerodynamic drag and noise in high-speed ***,a gradual optimization process is implemented to improve the most significant components that cause aerodynamic drag and *** optimizing the cross-sectional shape of the strips and insulators,the drag and noise caused by airflow separation and vortex shedding can be *** aerodynamic drag of insulator with circular cross section and strips with rectangular cross section is the *** insulators and optimizing the chamfer angle and height of the windward surface of the strips can improve the aerodynamic performance of the *** addition,the streamlined fairing attached to the base can eliminate the complex flow and shield the radiated *** contrast to the original pantograph design,the improved pantograph shows a 21.1%reduction in aerodynamic drag and a 1.65 dBA reduction in aerodynamic noise.

关键词： High-speed pantograph aerodynamic drag aerodynamic noise reduction optimizing

来源：评论

学校读者我要写书评

暂无评论

A Novel Vibration-Based Self-Adapting Method to Acquire Real-Time Following Distance for Virtually Coupled Trains

引用

IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 27-39页

作者： Qinglai Zhang Jianmin Gao Qing Wu Qinglie He Libin Tie Wanming Zhai Shengyang Zhu State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong University IEEE Centre for Railway Engineering Central Queensland University National Energy Railway Equipment Co. LTDNational Energy Group

Virtual coupling(VC) is an emerging technology for addressing the shortage of rail transportation capacity. As a crucial enabling technology, the VC-specific acquisition of train information, especially train following distance(TFD), is *** this paper, a novel method is proposed to acquire real-time TFD by analyzing the vibration response of the front and following trains, during which only onboard accelerometers and speedometers are required. In contrast to the traditional arts of train positioning, this method targets a relative position between two adjacent trains in VC operation, rather than the global positions of the trains. For this purpose, an adaptive system containing three strategies is designed to cope with possible adverse factors in train operation. A vehicle dynamics simulation of a heavy-haul railway is implemented for the evaluation of feasibility and performance. Furthermore, a validation is conducted using a set of data measured from in-service Chinese high-speed trains. The results indicate the method achieves satisfactory estimation accuracy using both simulated and actual data. It has favorable adaptability to various uncertainties possibly encountered in train operation. Additionally, the method is preliminarily proven to adapt to different locomotive types and even different rail transportation modes. In general, such a method with good performance, low-cost, and easy implementation is promising to apply.

关键词： Adaptive system train following distance (TFD) train positioning vehicle dynamics vibration response virtual coupling (VC)

来源：评论

学校读者我要写书评

暂无评论

Noise reduction mechanism of high-speed railway box-girder bridges installed with MTMDs on top plate

引用

railway engineering Science 2024年第4期32卷 518-532页

作者： Xiaoan Zhang Xiaoyun Zhang Jianjin Yang Li Yang Guangtian Shi School of Mechanical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Train and Track Research Institute State Key Laboratory of Rail Transit Vehicle SystemSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Service Environment and Intelligent Operation and Maintenance of Rail Transit Lanzhou Jiaotong UniversityLanzhou 730070China

The issue of low-frequency structural noise radiated from high-speed railway(HSR) box-girder bridges(BGBs) is a significant challenge worldwide. Although it is known that vibrations in BGBs caused by moving trains can be reduced by installing multiple tuned mass dampers(MTMDs) on the top plate, there is limited research on the noise reduction achieved by this method. This study aims to investigate the noise reduction mechanism of BGBs installed with MTMDs on the top plate. A sound radiation prediction model for the BGB installed with MTMDs is developed, based on the vehicle–track–bridge coupled dynamics and acoustics boundary element method. After being verified by field tested results, the prediction model is employed to study the reduction of vibration and noise of BGBs caused by the MTMDs. It is found that installing MTMDs on top plate can significantly affect the vibration distribution and sound radiation law of BGBs. However, its impact on the sound radiation caused by vibrations dominated by the global modes of BGBs is minimal. The noise reduction achieved by MTMDs is mainly through changing the acoustic radiation contributions of each plate of the bridge. In the lower frequency range, the noise reduction of BGB caused by MTMDs can be more effective if the installation of MTMDs can modify the vibration frequency and distribution of the BGB to avoid the influence of small vibrations and disperse the sound radiation from each plate.

关键词： High-speed railway Box-girder bridge MTMDs Noise control design Noise reduction mechanism

来源：评论

学校读者我要写书评

暂无评论

Integration of bio-inspired limb-like structure damping into motor suspension of high-speed trains to enhance bogie hunting stability

引用

railway engineering Science 2024年第3期32卷 324-343页

作者： Heng Zhang Liang Ling Sebastian Stichel Wanming Zhai State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China Department of Engineering Mechanics KTH Royal Institute of TechnologyStockholmSweden

Hunting stability is an important performance criterion in railway *** study proposes an incorporation of a bio-inspired limb-like structure(LLS)-based nonlinear damping into the motor suspension system for traction units to improve the nonlinear critical speed and hunting stability of high-speed trains(HSTs).Initially,a vibration transmission analysis is conducted on a HST vehicle and a metro vehicle that suffered from hunting motion to explore the effect of different motor suspension systems from on-track ***,a simplified lateral dynamics model of an HST bogie is established to investigate the influence of the motor suspension on the bogie hunting *** bifurcation analysis is applied to optimize the motor suspension parameters for high critical ***,the nonlinear damping of the bio-inspired LLS,which has a positive correlation with the relative displacement,can further improve the modal damping of hunting motion and nonlinear critical speed compared with the linear motor suspension ***,a comprehensive numerical model of a high-speed train,considering all nonlinearities,is established to investigate the influence of different types of motor *** simulation results are well consistent with the theoretical *** benefits of employing nonlinear damping of the bio-inspired LLS into the motor suspension of HSTs to enhance bogie hunting stability are thoroughly validated.

关键词： High-speed train Hunting stability Bio-inspired limb-like structure Motor suspension Nonlinear damping

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：