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分段线性系统经典数学模型的修正与动力学分析

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力学学报 2024年第1期56卷 225-235页

作者：张瑞良申永军韩东石家庄铁道大学机械工程学院石家庄050043 省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043

由于间隙的存在,很多机械系统可以简化为分段线性模型,而简化后的模型中副簧系统通常包含阻尼.在大多数文献建立的数学模型中,主、副系统的接触点与分离点固定在间隙处.文章研究发现,由于副簧系统中弹簧与阻尼的力学特性不同,主、副系... 详细信息

由于间隙的存在,很多机械系统可以简化为分段线性模型,而简化后的模型中副簧系统通常包含阻尼.在大多数文献建立的数学模型中,主、副系统的接触点与分离点固定在间隙处.文章研究发现,由于副簧系统中弹簧与阻尼的力学特性不同,主、副系统的接触点与分离点位置实际上是随着系统参数和运动状态而变化的.若忽视这一点,后续的包括分岔和混沌在内的动力学分析就会出现误差甚至错误.首先基于经典的数学模型,用数值方法揭示了在简谐激励下主系统未返回到间隙处就与副簧系统提前分离,证明了经典数学模型的不当之处.进一步研究发现主系统不仅会出现提前分离,还会出现接触滞后的现象.因此对系统的接触与分离条件提出了修正,得到了更合理的数学模型.研究发现修正后的接触点、分离点位置与修正前相差较大,修正后的幅频响应曲线与修正前存在一定差别;在复杂运动中,修正前后的运动性质也可能发生改变,证明了修正后的模型更加合理,更能反映工程实际.然后,采用平均法并对平均法的积分区间进行推广,求得了修正模型的幅频响应的解析解,并通过龙格库塔法验证了解析解的正确性.对解析解进行稳定性分析,得到了解析解的稳定性判别式.最后,探究了修正模型的副簧系统参数对主系统幅频响应的影响.

关键词：非线性振动分段线性系统平均法动力学行为接触

分数阶Rayleigh-Duffing系统的主共振

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振动与冲击 2024年第16期43卷 111-117页

作者：陈聚峰王媛媛申永军李向红石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043 石家庄铁道大学数理系石家庄050043 石家庄铁道大学机械工程学院石家庄050043

利用多尺度法研究了谐波激励下分数阶Rayleigh-Duffing系统的主共振。首先,利用多尺度法得到系统的一次近似解析解,通过数值仿真发现解析解与数值解吻合较好,验证了近似解析解的准确性;然后,建立了稳态解的幅频方程及相频方程,基于Lyapu... 详细信息

利用多尺度法研究了谐波激励下分数阶Rayleigh-Duffing系统的主共振。首先,利用多尺度法得到系统的一次近似解析解,通过数值仿真发现解析解与数值解吻合较好,验证了近似解析解的准确性;然后,建立了稳态解的幅频方程及相频方程,基于Lyapunov稳定性理论得到了稳态解的稳定性条件;最后,通过数值仿真并结合幅频曲线,分析发现非线性刚度系数、线性阻尼系数以及分数阶阶次等参数对系统动力学特性有重要影响,这对此类系统的优化和控制有重要意义。

关键词：分数阶导数多尺度法 Rayleigh-Duffing系统主共振

Thirty years of research on driving behavior active intervention:A bibliometric overview

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第5期10卷 721-742页

作者： Miaomiao Yang Qiong Bao yongjun shen Qikai Qu School of Transportation Southeast UniversityNanjing 211189China

To better understand the research focus and development direction in the field of driving behavior active intervention,thereby laying a scientific foundation for further research,we used the combination of topic words and keywords to retrieve relevant articles from the Core Collection Database of Web of Science(WOS).A total of 578 articles published from1992 to 2022 were finally ***,the time distribution characteristics,country distribution,institution distribution and main source journal distribution of published articles were ***,by using the Cite Space and VOSviewer software,cited reference co-citation analysis,keyword co-occurrence analysis and burst detection analysis were carried out respectively to visually explore the knowledge base,research topic,research frontier and development trend of this *** results indicate that the USA,Australia and China are the three most active countries in the studies of driving behavior active *** Analysis&Prevention,Transportation Research Part F:Traffic Psychology and Behavior,and Journal of Safety Research are widely selected journals for publications related to this *** research frontiers in the field of driving behavior active intervention focus on:“traffic safety and crashes analysis,as well as enforcement intervention”,“driving risk and education for young drivers”,“information provision and driving behavior”,“workload and situation awareness for automated driving”.It is worth noting that in recent years,“warning system”,“time”,“work load”have become research hotspots in this *** sum up,by a bibliometric overview of research on driving behavior active intervention over the past thirty years,this paper clarifies the development skeleton of this research field,determines its hot topics and research progress,and provides a reference for the follow-up exploratory scientific research in this field.

关键词： Driving behavior Active intervention Bibliometric analysis Mapping knowledge domain Visualization

Recent advancement of flow-induced piezoelectric vibration energy harvesting techniques:principles,structures,and nonlinear designs

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Applied Mathematics and Mechanics(English Edition) 2022年第7期43卷 959-978页

作者： Dongxing CAO Junru WANG Xiangying GUO S.K.LAI yongjun shen Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures Beijing 100124China School of Automation Beijing Information Science and Technology UniversityBeiing 100192China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center The Hong Kong Polytechnic UniversityKowloonHong KongChina State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Energy harvesting induced from flowing fluids(e.g.,air and water flows)is a well-known process,which can be regarded as a sustainable and renewable energy *** addition to traditional high-efficiency devices(e.g.,turbines and watermills),the micro-power extracting technologies based on the flow-induced vibration(FIV)effect have sparked great concerns by virtue of their prospective applications as a self-power source for the microelectronic devices in recent *** article aims to conduct a comprehensive review for the FIV working principle and their potential applications for energy ***,various classifications of the FIV effect for energy harvesting are briefly introduced,such as vortex-induced vibration(VIV),galloping,flutter,and wake-induced vibration(WIV).Next,the development of FIV energy harvesting techniques is reviewed to discuss the research works in the past three *** application of hybrid FIV energy harvesting techniques that can enhance the harvesting performance is also ***,the nonlinear designs of FIV-based energy harvesters are reported in this study,e.g.,multi-stability and limit-cycle oscillation(LCO)***,advanced FIV-based energy harvesting studies for fluid engineering applications are briefly ***,conclusions and future outlook are summarized.

关键词： vibration-driven energy harvesting flow-induced vibration(FIV) piezoelectric approach nonlinear design

Modeling,analysis,and simulation of X-shape quasi-zero-stiffness-roller vibration isolators

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Applied Mathematics and Mechanics(English Edition) 2022年第7期43卷 1027-1044页

作者： Xiaoye MAO Mengmeng YIN Hu DING Xiaofeng GENG yongjun shen Liqun CHEN Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Existing quasi-zero stiffness(QZS)isolators are *** terms of their advantages,a novel X-shape QZS isolator combined with the cam-roller-spring mechanism(CRSM)is *** from the existing X-shape isolators,oblique springs are used to enhance the negative stiffness of the ***,the CRSM is used to eliminate the gravity of the loading mass,while the X-shape structure leaves its static *** existing QZS isolators are demonstrated and classified according to their nonlinearity mechanisms and classical *** is shown that the oblique spring can realize negative stiffness based on the simplest *** X-shape has a strong capacity of loading mass,while the CRSM can achieve a designed restoring force at any *** proposed isolator combines all these advantages *** on the harmonic balance method(HBM)and the simulation,the displacement transmissibilities of the proposed isolator,the X-shape isolators just with oblique springs,and the X-shape isolators in the traditional form are *** results show that the proposed isolator has the lowest beginning isolation frequency and the smallest maximum displacement ***,it still has some disadvantages similar to the existing QZS *** means that its parameters should be designed carefully so as to avoid becoming a bistable system,in which there are two potential wells in the potential energy curve and thus the isolation performance will be worsened.

关键词： quasi-zero stiffness(QZS) cam-roller X-shape isolator nonlinear isolation

G6911干线巫镇高速沿溪线与越岭线方案比选研究

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公路交通技术 2024年第3期40卷 12-18页

作者：申勇军祝建平吴志强邹云招商局重庆交通科研设计院有限公司重庆400067

巫镇高速地处渝东北陕鄂渝三省交界的大巴山弧形构造地带,连接重庆奉溪高速和陕西平镇高速,是重庆第一条直连陕西的高速通道。为优化特长隧道和特大桥规模、降低施工难度,方案论证阶段采用“无人机航拍+VR技术”的创新手段辅助精细化选... 详细信息

巫镇高速地处渝东北陕鄂渝三省交界的大巴山弧形构造地带,连接重庆奉溪高速和陕西平镇高速,是重庆第一条直连陕西的高速通道。为优化特长隧道和特大桥规模、降低施工难度,方案论证阶段采用“无人机航拍+VR技术”的创新手段辅助精细化选线,剖析了山区高速在沿溪线和越岭线方案选择的关键技术难点,通过综合比选后得到了安全、经济、环保的路线方案。该研究可供山区高速公路科学选线参考。

关键词：巫镇高速渝东北越岭线沿溪线

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SHT-based public auditing protocol with error tolerance in FDL-empowered IoVs

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Digital Communications and Networks 2024年第1期10卷 142-149页

作者： Kui Zhu yongjun Ren Jian shen Pandi Vijayakumar Pradip Kumar Sharma School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China Peng Cheng Laboratory Shenzhen518000China Department of Computer Science and Engineering University College of Engineering TindivanamTamil Nadu604001India Department of Computing Science University of AberdeenAberdeenAB243UEUK

With the intelligentization of the Internet of Vehicles(lovs),Artificial Intelligence(Al)technology is becoming more and more essential,especially deep *** Deep Learning(FDL)is a novel distributed machine learning technology and is able to address the challenges like data security,privacy risks,and huge communication overheads from big raw data ***,FDL can only guarantee data security and privacy among multiple clients during data *** the data sets stored locally in clients are corrupted,including being tampered with and lost,the training results of the FDL in intelligent IoVs must be negatively *** this paper,we are the first to design a secure data auditing protocol to guarantee the integrity and availability of data sets in FDL-empowered ***,the cuckoo filter and Reed-Solomon codes are utilized to guarantee error tolerance,including efficient corrupted data locating and *** addition,a novel data structure,Skip Hash Table(SHT)is designed to optimize data ***,we illustrate the security of the scheme with the Computational Diffie-Hellman(CDH)assumption on bilinear *** theoretical analyses and performance evaluations demonstrate the security and efficiency of our scheme for data sets in FDL-empowered IoVs.

关键词： Internet of vehicles Federated deep learning Data security Data auditing Data locating and recovery

Research on the Integration of Structural Design and Material Parameters of Long-life Asphalt Pavement

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Journal of World Architecture 2022年第3期6卷 63-69页

作者： yongjun shen China Merchants Chongqing Communications Technology Research&Design Institute Co. LTD.Chongqing 400067China

In order to reduce the disease risk stemming from asphalt concrete pavement and ensure the safety of road operation,we should pay attention to the structural design of long-life asphalt pavement,strengthen the selection of long-term pavement materials,scientifically set the pavement mechanical performance indexes based on the calculation results of pavement structure thickness combination and modulus combination,and ensure the stability and durability of road pavement structure through the real-time establishment of three-dimensional finite element calculation model,as well as the integrated design that takes into consideration the aspects of road subgrade,semi-rigid base and asphalt layer.

关键词： Long life asphalt pavement Modulus combination Thickness combination Structural design

Maintenance and Management of High Slope of the Mountain Expressway

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Journal of Architectural Research and Development 2022年第3期6卷 61-67页

作者： yongjun shen China Merchants Chongqing Communications Technology Research&Design Institute Co. LTDChongqing 400067China

In order to effectively reduce the incidence of expressway operation safety accidents,one should pay attention to expressway safety management,especially high slope maintenance and *** conjunction,with the current situation of operation safety management of some expressways,many mountain expressways have high slope incidences from time to time,due to the extension of operating time,and inadequate maintenance ***,vehicle damage,and human death accidents caused by the high slope collapse,landslide,debris flow,and other disasters are often ***,it is essential to strengthen the maintenance and management of high slope in the mountain *** paper,will further elaborate the issues,which are related to the maintenance and management of high slopes in the in mountainous expressways.

关键词： Expressway High slope Disease Maintenance management