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Evolution of suspension bridge structural systems,design theories,and shape-finding methods:A literature survey

Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 225-244页

作者： wenming zhang Genmin Tian Yupeng Chen Key Laboratory of Concrete and Pre-stressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096China State Key Laboratory of Safety Durability and Healthy Operation of Long Span BridgesSoutheast UniversityNanjing 210096China

Modern suspension bridges exhibit a trend of lighter structures,more diversified structural forms,and longer spans,the latter already exceeding two *** performance under dead and live loads depends on their structural and main cable systems,while cablesupported bridges especially rely on the design analysis and construction control of the main *** literary survey systematically analyzes the research progress and state-ofthe-art status quo in the structural systems and design theories of suspension bridges,focusing on the structural systems,main cable shape analyses,live load effect analyses,and emerging lucrative research *** than 100 reliable references have been surveyed.(1)Multi-span or multi-main cable schemes appeal to increasing attention,which may become a better choice in terms of structural systems in scenarios with extremely long spans and heavy *** cable layouts,such as spatial main cables and hybrid cable-stayed suspension systems have also become feasible approaches for enhancing structural stiffness.(2)The shape-finding analysis during the construction phase is more complex and has more essential factors than that of the completed bridge *** theories combining analytical methods and finite element methods are more suitable for the shape-finding analysis of complex cable systems than any single theory of the two,especially for novel cable systems.(3)The live load effect analysis methods based on traditional deflection theory or modified/improved deflection theories still have wide applications,but the refined theory of treating hangers as discrete members is also constantly developing,which is expected to provide new ideas for more complex structural analysis under the different types of live loads and their distribution forms.

关键词： Suspension bridges Structural system Cable analysis Shape-finding analysis Construction control and calculation Live load effect

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Thermal noise-driven resonant sensors

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Microsystems & Nanoengineering 2024年第3期10卷 259-271页

作者： Yan Qiao Alaaeldin Elhady Mohamed Arabi Eihab Abdel-Rahman wenming zhang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Systems Design Engineering University of WaterlooWaterlooONCanada

MEMS/NEMS resonant sensors hold promise for minute mass and force ***,one major challenge is that conventional externally driven sensors inevitably encounter undesired intrinsic noise,which imposes a fundamental limitation upon their signal-to-noise ratio(SNR)and,consequently,the ***,this restriction becomes increasingly pronounced as sensors shrink to the *** this work,we propose a counterintuitive paradigm shift that turns intrinsic thermal noise from an impediment to a constituent of the sensor by harvesting it as the driving force,obviating the need for external actuation and realizing‘noise-driven’*** sensors employ the dynamically amplified response to thermal noise at resonances for stimulus *** demonstrate that lightly damped and highly compliant nano-structures with high aspect ratios are promising candidates for this class of *** overcome the phase incoherence of the drive force,three noise-enabled quantitative sensing mechanisms are *** validated our sensor paradigm by experimental demonstrating noise-driven pressure and temperature ***-driven sensors offer a new opportunity for delivering practical NEMS sensors that can function at room temperature and under ambient pressure,and a development that suggests a path to cheaper,simpler,and low-power-consumption sensors.

关键词： noise resonant overcome

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Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan ZHAO Han YAN Ge YAN Ao CHEN wenming zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

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Enhancing I0/I-Conversion Efficiency by Starch Confinement in Zinc-Iodine Battery

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Energy & Environmental Materials 2024年第1期7卷 118-124页

作者： Danyang Zhao Qiancheng Zhu Qiancheng Zhou wenming zhang Ying Yu Shuo Chen Zhifeng Ren Institute of Nanoscience and Nanotechnology College of Physical Science and Technology Central China Normal University National & Local Joint Engineering Laboratory of New Energy Photoelectric Devices College of Physics Science and Technology Hebei University Department of Physics and Tc SUH University of Houston

The redox couple of I0/I-in aqueous rechargeable iodine-zinc（I2-Zn）batteries is a promising energy storage resource since it is safe and costeffective,and provides steady output ***,the cycle life and efficiency of these batteries remain unsatisfactory due to the uncontrolled shuttling of polyiodide（I3-and I5-） and side reactions on the Zn anode.

关键词： aqueous battery conversion efficiency iodine–zinc battery starch confinement

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Enhancing I^(0)/I^(-)Conversion Efficiency by Starch Confinement in Zinc-lodine Battery

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Energy & Environmental Materials 2024年第1期7卷 114-120页

作者： Danyang Zhao Qiancheng Zhu Qiancheng Zhou wenming zhang Ying Yu Shuo Chen Zhifeng Ren Institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China National&Local Joint Engineering Laboratory of New Energy Photoelectric Devices College of Physics Science and TechnologyHebei UniversityBaoding 071002China Department of Physics and TcSUH University of HoustonHouston Texas 77204USA

The redox couple of I^(0)/I^(-)in aqueous rechargeable iodine–zinc(I^(2)-Zn)batteries is a promising energy storage resource since it is safe and cost-effective,and provides steady output ***,the cycle life and efficiency of these batteries remain unsatisfactory due to the uncontrolled shuttling of polyiodide(I_(3)^(-)and I_(5)^(-))and side reactions on the Zn *** is a very low-cost and widely sourced food used daily around the world.“Starch turns blue when it encounters iodine”is a classic chemical reaction,which results from the unique structure of the helix starch molecule–iodine *** by this,we employ starch to confine the shuttling of polyiodide,and thus,the I^(0)/I^(-)conversion efficiency of an I^(2)-Zn battery is clearly *** to the detailed characterizations and theoretical DFT calculation results,the enhancement of I^(0)/I^(-)conversion efficiency is mainly originated from the strong bonding between the charged products of I_(3)^(-)and I_(5)^(-)and the rich hydroxyl groups in *** work provides inspiration for the rational design of high-performance and low-cost I^(2)-Zn in AZIBs.

关键词： aqueous battery conversion efficiency iodine-zinc battery starch confinement

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Application of Perceived Teaching with Moderate Elimination of“Graphics”in Architectural Design Courses

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Journal of Landscape Research 2024年第1期16卷 43-47页

作者： LIU Hongyun WANG Xingyi LI Tianjiao CHEN Yongsheng zhang wenming School of Forestry&Landscape Architecture Anhui Agricultural UniversityHefeiAnhui 230036China School of Foreign Languages Anhui Agricultural UniversityHefeiAnhui 230036China

Starting from the traditional form of“graphic”architectural education,this paper explores a teaching method of entity construction experience,instrument assistance,and digital virtual expression symbiosis symbiosis from three aspects:environmental perception,ontology perception,and extension *** physical perception as a medium,and gradually rising from active perception to a comprehensive expression of visual audience perception through practical operation,it allows students to have a more comprehensive understanding of the meaning of architectural design on the basis of the“graphic”expression paradigm.

关键词： Graphics Beaux-Arts system Perceived teaching Digital technique Constructing Experience

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流动的非粮种植与二元土地流转市场——一项土地流转中农业经营模式的双案例分析

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山东大学学报（哲学社会科学版） 2024年第5期 97-109页

作者：张文明刘江华东师范大学社会发展学院上海200241

造成土地流转市场分化现象的因素不仅包括土地禀赋、流转主体和外在环境,农业经营模式本身也会产生影响。根据不同作物的种植特性,以作物-土地关联机制为切入点,对山东某地区的非粮种植及其参照案例进行比较。研究发现,非粮种植和粮食... 详细信息

造成土地流转市场分化现象的因素不仅包括土地禀赋、流转主体和外在环境,农业经营模式本身也会产生影响。根据不同作物的种植特性,以作物-土地关联机制为切入点,对山东某地区的非粮种植及其参照案例进行比较。研究发现,非粮种植和粮食种植之间不同的作物-土地关联机制影响经营流动性,非粮作物需要流动经营,粮食作物采取固定经营。不同的作物类型和经营模式对土地流转市场产生影响,导致流转对象、合约形式和流转价格发生分化,呈现出二元土地流转市场形态。特别是非粮作物与粮食作物在土壤损害、种植风险、关系强度和交易成本等方面的差异,导致非粮种植的土地流转价格远高于粮食种植。

关键词：农业经营模式二元流转市场作物-土地关联非粮化灵活合约

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制造景观:项目经营下的乡村建设

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华中农业大学学报（社会科学版） 2024年第3期 190-201页

作者：刘江张文明华东师范大学社会发展学院上海200241

项目下乡中的经营行为引发了景观化建设现象,研究以湖北T村为例,从空间实践、生产机制和治理效应三方面对此展开分析。从景观化的空间实践来看,T村在项目试点中的密集投入和差异化建设,导致景观密集生产和村庄空间分化,并凸显了景观的... 详细信息

项目下乡中的经营行为引发了景观化建设现象,研究以湖北T村为例,从空间实践、生产机制和治理效应三方面对此展开分析。从景观化的空间实践来看,T村在项目试点中的密集投入和差异化建设,导致景观密集生产和村庄空间分化,并凸显了景观的工具价值。从景观化的生产机制来看,主要源于对项目的经营。在决策层面,省级政府以行政发包配合项目下发,容易导致资源堆砌和重复试点;在下发过程中,县乡政府缺少代理人,强化了项目的集中下发冲动;在执行层面,项目捆绑产生了较强的执行压力,导致目标对照基础上的空间营造。从景观化的治理效应来看,一方面有利于空间更新、基础设施改善和组织权威强化,另一方面又导致景观的后续养护难题、对生活景观的排斥、对村民生计的影响以及村民隔阂等。这种好坏参半的治理效应体现了“项目悬浮”问题,即项目与村民需求脱节。最后,研究还提出了基层社会从“经营项目”向“经营空间”的延伸。

关键词：景观化建设经营项目美丽乡村新代理人经营空间

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基于深度强化学习算法的纯电动矿用汽车再生制动策略研究

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工程科学学报 2024年第3期46卷 503-513页

作者：杨威威罗登昊张文明北京科技大学机械工程学院车辆工程系北京100083

以载重50 t纯电动矿用汽车为研究对象,提出了一种基于深度强化学习优化算法的再生制动回馈策略.首先建立了纯电动矿用自卸车的数学模型.随后提出了一种考虑载重和坡度变化的基于自动熵调节Soft actor-critic (SAC)和深度确定性策略梯度... 详细信息

以载重50 t纯电动矿用汽车为研究对象,提出了一种基于深度强化学习优化算法的再生制动回馈策略.首先建立了纯电动矿用自卸车的数学模型.随后提出了一种考虑载重和坡度变化的基于自动熵调节Soft actor-critic (SAC)和深度确定性策略梯度算法(DDPG)的能量管理策略.其中车速、加速度、车辆质量与道路坡度、动力电池荷电状态(SOC)及充放电倍率作为状态变量;变速箱挡位作为动作变量;动力电池SOC及电池寿命作为奖励函数.仿真结果表明,基于动态规划的控制策略和所提出的基于SAC算法与基于DDPG算法的优化控制策略回馈效率分别提高了18.15%、17.18%和16.63%,电池寿命分别提升了57.31%、56.87%和57.38%.最后通过比较两种基于深度强化学习算法策略的奖励曲线,可以看出与基于DDPG算法的控制策略相比,所提出的基于SAC的能量管理控制策略的收敛速度提升了166.7%.

关键词：纯电动矿用汽车再生制动电池寿命控制策略强化学习

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新中国乡村教师媒介形象的国家叙事研究——基于《人民日报》报道的文本分析(1949-2021)

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华东师范大学学报（哲学社会科学版） 2024年第2期56卷 120-131,181页

作者：张文明陈嘉晟华东师范大学国家教育宏观政策研究院上海200062 华东师范大学教育学部上海教育科学研究院

1949年以来,乡村教师的媒介形象在国家叙事中是如何被呈现的?这是一个值得在推进一系列乡村教师支持计划之际深入探讨的问题。通过选取1949~2021年《人民日报》关于乡村教师的报道进行LDA主题建模与案例分析,可以呈现不同时代、不同阶... 详细信息

1949年以来,乡村教师的媒介形象在国家叙事中是如何被呈现的?这是一个值得在推进一系列乡村教师支持计划之际深入探讨的问题。通过选取1949~2021年《人民日报》关于乡村教师的报道进行LDA主题建模与案例分析,可以呈现不同时代、不同阶段乡村教师媒介形象的国家建构与国家期待。研究发现:其一,乡村教师的报道焦点从地方典型经验向国家视角转变并且数量持续上升,说明国家对乡村教师问题的重视度逐渐提升;其二,乡村教师媒介形象经历了从集体化时期的“国家集体主义奉献者”到改革开放时期的“地方实用主义奋斗者”再到乡村振兴时期的“城乡公平主义实践者”的变化;其三,“又红又专”的道德话语逐渐淡化,而基于教师个体乡土情感的在地化形象建构得到强化,塑造了“扎根泥土的向日葵”的职业知识分子理想形象,其价值导向意义鲜明。研究认为:新中国成立以来,乡村教师媒介形象的变迁折射出了乡村教育从“外生扶持”向“内生发展”模式转向,其动力机制是城乡均衡与教育公平的理念及政策。

关键词：乡村教师媒介职业形象人民日报国家建构价值导向

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