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基于布拉格光栅传感器的桥墩基础冲刷动态监测试验

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中国公路学报 2014年第5期27卷 125-130页

作者：熊文 cai c s 叶见曙东南大学交通学院江苏南京210096 路易斯安那州立大学土木与环境工程系路易斯安那巴吞鲁日la70803

为长期有效监测桥墩基础冲刷作用,基于露出河床的布拉格光栅传感器(FBG传感器)的不同相对位置以及对水流力和结构弯曲的波长变化,提出了一种新的桥墩冲刷动态监测方法;详细介绍了其工作原理,并给出基于该工作原理的监测设计方案,同时介... 详细信息

为长期有效监测桥墩基础冲刷作用,基于露出河床的布拉格光栅传感器(FBG传感器)的不同相对位置以及对水流力和结构弯曲的波长变化,提出了一种新的桥墩冲刷动态监测方法;详细介绍了其工作原理,并给出基于该工作原理的监测设计方案,同时介绍了监测设备的制作步骤和设备保护措施设计;按照所提出的监测原理以及监测设备,采用足尺试验模型于实验室水槽中进行基础冲刷模拟试验,模拟了监测冲刷和冲刷回填全过程。结果表明:通过对2次典型试验工况结果的数据分析,证明FBG传感器可实现长期实时监测桥墩冲刷发展和冲刷后河床回填的全过程,为今后实际工程中的桥墩基础冲刷长期实时监测提供理论依据;该监测设备耐久性高,数据准确稳定,不受外界因素(如极端天气)干扰,具备良好的野外应用可行性与优越性。

关键词：桥梁工程桥墩试验研究布拉格光纤光栅传感器冲刷动态监测

基于力学与造价的cFRP-钢组合拉索斜拉桥设计理论

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中国公路学报 2012年第4期25卷 97-106页

作者：熊文肖汝诚 cai c s 叶见曙东南大学桥梁工程系江苏南京210096 路易斯安那州立大学土木与环境工程系路易斯安那巴吞鲁日la70803 同济大学桥梁工程系上海200092

针对1 400～2 800m主跨斜拉桥整体刚度不足的问题,提出一种新型结构方案——碳纤维增强塑料(cFRP)-钢组合拉索斜拉桥。该方案将cFRP斜拉索与传统钢斜拉索同时应用于斜拉桥中,组合2种材料高强轻质及弹性模量高的优点,以达到提高斜拉桥整... 详细信息

针对1 400～2 800m主跨斜拉桥整体刚度不足的问题,提出一种新型结构方案——碳纤维增强塑料(cFRP)-钢组合拉索斜拉桥。该方案将cFRP斜拉索与传统钢斜拉索同时应用于斜拉桥中,组合2种材料高强轻质及弹性模量高的优点,以达到提高斜拉桥整体刚度的设计目的。通过基于力学与造价的参数分析提出该组合拉索斜拉桥的3种设计原则:等安全系数等效刚度最优、等安全系数等效刚度性价比最优、等造价等效刚度最优,并分别给出详细的设计步骤及设计用图。最后,进行了多种方案1 400m主跨斜拉桥试设计。结果表明:cFRP-钢组合拉索斜拉桥在力学与经济性方面均具有一定优势,其工程应用具有可行性,是主跨为1 400～2 800m斜拉桥的优选方案之一。

关键词：桥梁工程 cFRP-钢组合拉索刚度经济性能斜拉桥设计理论

state-of-the-art review of the development and application of bridge rotation construction methods in china

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science china(Technological sciences) 2021年第6期64卷 1137-1152页

作者： sU Miao WANG Jun PENG Hui cai cs DAI GongLian school of civil Engineering Changsha University of Science and TechnologyChangsha 410114China Department of civil and Environmental Engineering University of CaliforniaBerkeleyCA 94720USA Department of civil and Environmental Engineering Louisiana State UniversityBaton RougeLA 70803USA school of civil Engineering Central South UniversityChangsha 410075China

This work provides a comprehensive review of the development and applications of bridge rotation construction methods(BRMs) and related critical construction technologies in china. A brief history of BRMs and an outline of their categories,including the rotating structural system, are given first. subsequently, a discussion on the recent practice of BRMs in china is carried out from three types of bridges:(1) continuous beam and rigid frame bridges;(2) arch bridges;(3) cable-stayed *** each group, a survey of the vital bridge cases that have adopted BRMs in china in the past two decades is provided. Key parameters, including the structure weight of rotation, maximum cantilever span, and rotation duration, are also compared and discussed. Afterward, the principles and applications of the weighing test and the spherical hinge stability, which are both related to the safety of the horizontal rotation construction process, are analyzed in the paper. Additionally, the limitations of BRMs are presented and discussed, and the article concludes with a summary of the current use and future trend of BRMs. The information and experience of BRMs provided in this work can be referenced by engineers and researchers who are devoted to the construction of bridges.

关键词： bridge engineering traffic engineering swing method vertical rotation weighting test spherical hinge

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高墩连续桥在移动车载作用下的横向振动分析

振动与冲击 2013年第3期32卷 35-40页

作者：殷新锋刘扬 cai c s 长沙理工大学土木与建筑学院长沙410004 Louisiana state University School of Civil and Environment EngineeringL ABaton Rougelouisiana 70803

将轮胎与路面之间的面接触引入车-桥耦合模型基础上,进一步考虑车辆的横向自由度,提出一种新的车辆模型研究移动车载作用下桥梁的横向振动。将车辆轮胎模拟成一个三维弹簧模型,轮胎与地面的接触面模拟成长方形,通过接触面间的位移协调... 详细信息

将轮胎与路面之间的面接触引入车-桥耦合模型基础上,进一步考虑车辆的横向自由度,提出一种新的车辆模型研究移动车载作用下桥梁的横向振动。将车辆轮胎模拟成一个三维弹簧模型,轮胎与地面的接触面模拟成长方形,通过接触面间的位移协调条件和力相互作用建立车-桥耦合振动方程。考虑影响接触面间横向力大小的三种重要参数如:滑移角、侧偏角、轮胎"s"形运动对耦合系统的影响;并与炉坪大桥实测数据比较,验证该方法的正确性,并分析接触面积、车速等对横向振动的影响。

关键词：车-桥耦合振动桥梁模型车辆模型横向振动面接触

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冲刷环境对桥墩冲刷空间形态影响的仿真分析

哈尔滨工业大学学报 2016年第3期48卷 108-114页

作者：熊文姚浩 cai c.s. 叶见曙东南大学交通学院南京210096 路易斯安那州立大学土木与环境工程系美国路易斯安那州巴吞鲁日70803

为研究环境对桥墩冲刷的影响,基于K-ε湍流模型建立了桥墩冲刷及冲刷环境数值仿真模型.对其三维仿真建模过程中的4个关键问题分别进行深入研究并提出优选的解决方法,特别关注三维边界条件的动态更新以及计算收敛性的算法改进.进而利用**... 详细信息

为研究环境对桥墩冲刷的影响,基于K-ε湍流模型建立了桥墩冲刷及冲刷环境数值仿真模型.对其三维仿真建模过程中的4个关键问题分别进行深入研究并提出优选的解决方法,特别关注三维边界条件的动态更新以及计算收敛性的算法改进.进而利用***经典实验对提出的桥墩冲刷精细化仿真方法从空间形态的角度进行多方面准确性验证.最后基于该精细化仿真方法,对cFD计算软件Fluent二次开发,进行精细化参数分析.计算结果表明:桥墩尺寸与最大冲刷深度以及流速与最大冲刷深度均存在近似线性关系,选择合适的桥墩形式、降低桥墩有效宽度、降低墩前水流流速以及选择合适的水流深度均可明显降低桥墩冲刷深度.不同冲刷环境参数取值对桥墩冲刷空间形态所产生的不同影响可以为桥墩主动抗冲刷设计与选型提供合理的理论基础与依据.

关键词：桥墩冲刷仿真建模几何参数流场形态参数参数分析抗冲刷设计

Experimental and theoretical analysis of loading characteristics of electret fi lter media for charged particles

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PARTIcUOLOGY 2024年第10期93卷 87-98页

作者： cai, Yiqi cai, Rongrong Zhang, Lizhi south china Univ Technol Sch Chem & Chem Engn Key Lab Enhanced Heat Transfer & Energy Conservat Educ Minist Guangzhou 510640 Peoples R China south china Univ Technol State Key Lab Subtrop Bldg Sci Guangzhou 510640 Peoples R China

The degradation of filtration performance in electret filter media during usage poses a significant challenge. Pre-charging of aerosols has been identified as an effective method to mitigate this issue. However, the effects of particle charging characteristics on the loading characteristics of electret filters still need a comprehensive understanding. In this study, a needle-cylinder corona charger was employed to pre-charge aerosols, and the particle charge state was determined by multiphysics simulation. The effects of particle charge polarity and charge quantity on the loading performance of the electret filter were quantitatively investigated. The results showed that the particle charge polarity had a negligible impact on the loading performance under the condition of the equivalent particle charge quantity. In addition, the charged particles effectively improved the efficiency degradation during the loading process of electret media, with higher charge quantities resulting in more pronounced improvements. The electrostatic attenuation factor showed a negative exponential correlation with the particle charge quantity. This was attributed to the uneven particle deposition on fiber surface due to the attraction of charged particles by the opposite charges on the electret fibers, which alleviated the effect of electrostatic shielding. (c) 2024 Published by Elsevier B.V. on behalf of chinese society of Particuology and Institute of Process Engineering, chinese Academy of sciences.

关键词： Electret filter charged particles Loading characteristic corona charging Electrostatic screening NUMERIcAL-sIMULATION FILTER FILTRATION AEROsOL PERFORMANcE cOLLEcTION TRANsPORT MODEL

shor's algorithm does not factor large integers in the presence of noise

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science china(Information sciences) 2024年第7期67卷 305-320页

作者： Jin-Yi cai college of Letters and science University of Wisconsin

We consider shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise shor's algorithm rotation gates quantum computing prime factorization

Key Technologies and Prospects for Electric Vehicles Within Emerging Power systems: Insights from Five Aspects

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csEE Journal of Power and Energy systems 2024年第2期10卷 439-447页

作者： Yalun Li Minggao Ouyang c.c.chan Xueliang sun Yonghua song Wei cai Yilin Xie Yuqiong Mao Department of Electrical Engineering and School of Vehicle and MobilityTsinghua UniversityBeijing 100084China school of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999077China Department of Mechanical and Materials Engineering University of Western OntarioLondonON N6A 3K7Canada state Key Laboratory of Internet of Things for smart city University of MacaoTaipaMacao 999078China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China school of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbin 150080China

The energy revolution requires coordination in energy consumption, supply, storage and institutional *** energy generation technologies, along with their associated costs, are already fully equipped for large-scale ***, energy storage remains a bottleneck, and solutions areneeded through the use of electric vehicles, which traditionallyplay the role of energy consumption in power systems. Toclarify the key technologies and institutions that support EVsas terminals for energy use, storage, and feedback, the csEEJPEs forum assembled renowned experts and scholars in relevantfields to deliver keynote reports and engage in discussions ontopics such as vehicle–grid integration technology, advancedsolid-state battery technology, high-performance electric motortechnology, and institutional innovation in the industry *** experts also provided prospects for energy storage andutilization technologies capable of decarbonizing new powersystems.

关键词： Electric vehicles engineering philosophy highpower density motor new power system solid state batteries vehicle grid integration.

Whittle’s Index Based sensor scheduling for Multiprocess systems Under Dos Attacks

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Journal of systems science & complexity 2024年第1期37卷 329-350页

作者： cai Zai DING Kemi shenzhen Key Laboratory of control Theory and Intelligent systems Southern University of Science and TechnologyShenzhen 518055China.

In this paper,the authors consider how to design defensive countermeasures against Dos attacks for remote state estimation of multiprocess *** each system,a sensor will measure its state and transmits the data packets through an unreliable channel which is vulnerable to be jammed by an *** limited communication bandwidth,only a subset of sensors are allowed for data transmission,and how to select the optimal one to maximize the accuracy of remote state estimation is the focus of the proposed *** authors first formulate this problem as a Markov decision process and investigate the existence of optimal ***,the authors demonstrate the piecewise monotonicity structure of optimal *** the difficulty of obtaining an optimal policy of large-scale problems,the authors develop a suboptimal heuristic policy based on the aforementioned policy structure and Whittle’s ***,a closed form of the indices is derived in order to reduce implementation complexity of proposed scheduling policy and numerical examples are provided to illustrate the proposed developed results.

关键词： Dos attacks Kalman filter remote state estimation Whittle’s index.