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Parameter effects on the dynamic characteristics of a super-long-span triple-tower suspension bridge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 305-316页

作者： Hao WANG Ke-guan ZOU ai-qun li Chang-ke JIAO College of Civil Engineering Southeast University Nanjing 210096 China

A 3D finite element model for the Taizhou Yangtze River Bridge,the first triple-tower long-span suspension bridge in China,is established based on the nonlinear finite element software ABAQUS,and the dynamic characteristics of the bridge are analyzed using the LANCZOS eigenvalue solution method. The study focuses on the effects of the vertical,lateral and torsional stiffness of the steel box girder,the rigid central buckle and the elastic restraints connecting the towers and the steel box girder on the dynamic characteristics of the triple-tower suspension bridge. Our results show that,in general,the dynamic characteristics of the triple-tower suspension bridge are similar to those of two-tower suspension bridges. The vertical,lateral and torsional stiffness of the steel box girder have different effects on the dynamic characteristics of triple-tower suspension bridges. The elastic re-straints have a more significant effect on the dynamic characteristics than the central buckle,and decreasing the stiffness of the elastic restraints results in the appearance of a longitudinal floating vibration mode of the bridge. Also,rigid central buckles have a greater influence on the dynamic characteristics of triple-tower suspension bridges than on those of two-tower suspension bridges. The results obtained could serve as a valuable numerical reference for analyzing and designing super-long-span triple-tower suspension bridges.

关键词： Suspension bridge Taizhou Bridge Triple-tower Dynamic characteristics Super-long-span

Design and experimental verification of a new multi-functional bridge seismic isolation bearing

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 904-914页

作者： Chen-xi XING Hao WANG ai-qun li Ji-rong WU MOE Key Laboratory of Concrete and Prestressed Concrete Structures Southeast UniversityNanjing 210096China

A new multi-functional bridge seismic isolation bearing(MFBSIB) is designed and its mechanical model is developed in this *** an upper sliding device and a lower energy dispassion isolation device effectively,the new MFBSIB can adjust the deformation caused by temperature,vehicle breaks,and concrete creep,etc.,in addition to dissipating *** switch of 'slide-isolation' is achieved and the efficiency of both upper and lower parts is validated through experiment with a *** shear performance curve established in this paper is verified to be efficient in describing the mechanical characteristics of the bearing through *** is proved through both numerical calculation and experimental analysis that the new MFBSIB is endowed with enough vertical rigidity,good energy dissipation ability,stable overall performance,and good realization in expected *** performance is slightly influenced by shear stress,while affected by vertical pressure,loading frequency,slide limit,etc.,*** results could provide reference for study and application of the new MFBSIB.

关键词： Seismic isolation bearing Sliding device Finite element analysis Model experiment Bridge

Digital simulation of 3D turbulence wind field of Sutong Bridge based on measured wind spectra

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 91-104页

作者： Hao WANG Zhou-hong ZONG ai-qun li Teng TONG Jie NIU Wen-ping DENG Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096China Key Laboratory of Environmental Impact and Structural Safety in Engineering China University of Mining&TechnologyXuzhou 221116China

Time domain analysis is an essential implement to study the buffeting behavior of long-span bridges for it can consider the non-linear effect which is significant in long-span bridges. The prerequisite of time domain analysis is the accurate description of 3D turbulence winds. In this paper, some hypotheses for simplifying the 3D turbulence simulation of long-span cable-stayed bridges are conducted, considering the structural characteristics. The turbulence wind which is a 3D multivariate stochastic vector process is converted into four independent 1D univariate stochastic processes. Based on recorded wind data from structural health monitoring system (SHMS) of the Sutong Bridge, China, the measured spectra expressions are then presented using the nonlinear least-squares fitting method. Turbulence winds at the Sutong Bridge site are simulated based on the spectral representation method and the Fast Fourier transform (FFT) technique, and the relevant results derived from target spectra including measured spectra and recommended spectra are compared. The reliability and accuracy of the presented turbulence simulation method are validated through comparisons between simulated and target spectra (measured and recommended spectra). The obtained turbulence si-mulations can not only serve further analysis of the buffeting behavior of the Sutong Bridge, but references for structural anti-wind design in adjacent regions.

关键词： Turbulence simulation Spectral representation method Fast Fourier transform (FFT) Cable-stayed bridges Struc-tural health monitoring system (SHMS) Power spectral density

基于多重调谐质量阻尼器的苏通大桥抖振位移最优控制的数值模拟（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第10期15卷 798-812页

作者： Hao WANG Tian-you TAO Huai-yu CHENG ai-qun li Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education Southeast University

研究目的:为超大跨度斜拉桥抗风设计与抖振控制提供参考。研究方法:基于ANSYS建立了苏通大桥三维有限元模型,并在MATLAB平台模拟了苏通大桥三维脉动风场。考虑主梁断面气动自激力,进行了苏通大桥抖振时域分析。根据苏通大桥动力特性和... 详细信息

研究目的:为超大跨度斜拉桥抗风设计与抖振控制提供参考。研究方法:基于ANSYS建立了苏通大桥三维有限元模型,并在MATLAB平台模拟了苏通大桥三维脉动风场。考虑主梁断面气动自激力,进行了苏通大桥抖振时域分析。根据苏通大桥动力特性和抖振时域分析结果,重点分析了多重调谐质量阻尼器(MTMD)用于抖振控制的参数敏感性。考虑MTMD的控制效果、建造费用、施工难度及鲁棒性等因素建立了关于MTMD设计参数的目标函数,并基于一阶优化算法进行目标函数最优解的非线性搜索,据此获得了MTMD在约束条件下的最优设计参数。重要结论:1.苏通大桥侧向抖振位移主要由第一阶侧弯振型控制,竖向抖振位移主要由第一阶竖弯振型控制;***的控制效果对设计参数的变化十分敏感,其中质量比和频带宽敏感性更强;***的最优设计参数可以通过一阶优化算法获得,并可通过零阶优化算法对优化结果进行验证;4.采用优化后的MTMD设计参数,苏通大桥的抖振响应可以得到明显抑制,且侧向抖振控制效果更加明显。

关键词：大跨斜拉桥抖振响应振动控制多重调谐质量阻尼器(MTMD) 控制效果优化算法

一种可滑移式铅芯橡胶支座的显式数值模拟与试验验证(英文)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第5期18卷 363-376页

作者： Yi-feng WU Hao WANG ai-qun li Dong-ming FENG Ben SHA Yu-ping ZHANG School of Civil Engineering Southeast University Nanjing 210096 China Beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering and Architecture Beijing 100044 China Department of Civil Engineering and Engineering Mechanics Columbia University New York NY 10027 USA

目的:随着隔震技术在工程结构中的逐步推广应用,橡胶隔震支座的试验与数值模拟都得到国内外工程研究人员的重视。其中后者因支座大变形时计算较难收敛、铅芯与周边橡胶以及钢板的复杂接触关系较难模拟、采用隐式积分算法时计算规模较难... 详细信息

目的:随着隔震技术在工程结构中的逐步推广应用,橡胶隔震支座的试验与数值模拟都得到国内外工程研究人员的重视。其中后者因支座大变形时计算较难收敛、铅芯与周边橡胶以及钢板的复杂接触关系较难模拟、采用隐式积分算法时计算规模较难控制等问题,目前仍是这一方向的研究热点。本文旨在探讨基于显式积分算法对一种新型可滑移式铅芯橡胶支座进行准确可行的数值模拟的方法。创新点:1.探究基于显式积分算法的隔震支座数值模拟方法;2.采取多种方法有效地控制了数值模拟计算规模,同时实现了较高的数值模拟精度;3.采用程序中提供的3种接触方式较好地模拟了支座中存在的复杂接触关系。方法:本文主要采用4种方法减小数值模拟计算规模:1.激活程序内置的质量缩放功能;2.合理增大支座中对支座竖向刚度与水平剪切性能影响较小的非关键部件——叠层钢板的厚度;3.合理减小叠层钢板的弹性模量;4.考虑到支座中所有材料均未考虑材料的率变效应,即加载速率对支座的力学性能没有影响,本文数值模拟中所用加载频率为实际加载频率的10倍。此外,本文采用了一般接触、绑定接触与单边接触模拟支座中不同的接触关系。结论:1.显式积分的计算时间步长由2.4×10-7 s增大到3.5×10-6 s;2.与试验结果对比验证了本文提出的基于显式积分算法对该新型可滑移式铅芯橡胶支座进行数值模拟的方法的准确实用性;3.该支座在纯压作用下,部分铅芯发生塑性变形,而在最大剪切位移时,铅芯发生了很大的塑性流动变形;4.与采用隐式算法对该支座进行数值模拟研究所用时间相比,显式算法所用时间少很多。

关键词：显式算法可滑移式铅芯支座计算时间步长接触关系试验验证

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-qun Fu Hong-Wei li Jian-Hong Shi Tan li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

RASSF1A与GSTP1基因甲基化检测对前列腺癌诊断价值的研究

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中华肿瘤防治杂志 2017年第17期24卷 1220-1222页

作者：李爱群于静李晓鲲 ZHU ai-qing 滨州医学院烟台附属医院急诊科山东烟台264100 滨州医学院烟台附属医院病理科山东烟台264100

目的前列腺癌的早期诊断缺乏特异性,联合基因甲基化检测可能具有一定的价值。本研究探讨RASSF1A与GSTP1基因甲基化联合检测对前列腺癌的诊断价值。方法收集滨州医学院烟台附属医院泌尿外科行手术治疗并经过病理组织学确诊的前列腺癌患... 详细信息

目的前列腺癌的早期诊断缺乏特异性,联合基因甲基化检测可能具有一定的价值。本研究探讨RASSF1A与GSTP1基因甲基化联合检测对前列腺癌的诊断价值。方法收集滨州医学院烟台附属医院泌尿外科行手术治疗并经过病理组织学确诊的前列腺癌患者42例作为病例组,另选取同期健康体检者40名作为对照组。于术前或体检时获取血液标本,提取DNA后通过实时荧光定量甲基化特异PCR(MSP)法检测RASSF1A与GSTP1基因甲基化率,分析年龄、性别和临床分期等指标对甲基化的影响。探讨两类基因甲基化联合检测对前列腺癌诊断的敏感性和特异性。结果病例组RASSF1A基因甲基化率为66.67%(28/42),GSTP1基因甲基化率为61.90%(26/42);对照组RASSF1A基因甲基化率为15.00%(6/40),GSTP1基因为10.00%(4/40)。各临床病理特征与患者RASSF1A和GSTP1基因甲基化均不存在明显的相关性,均P值>0.05。RASSF1A和GSTP1基因甲基化均为前列腺癌发病的独立危险因素,均P值<0.05。联合检测RASSF1A和GSTP1基因甲基化能够明显提高诊断的敏感性(83.33%)及特异性(83.87%)。结论 RASSF1A和GSTP1基因甲基化联合检测可显著提升前列腺癌的诊断水平。

关键词：基因甲基化前列腺癌诊断

PS-CoT-Adapter: adapting plan-and-solve chain-of-thought for ScienceQA

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Science China(Information Sciences) 2025年第1期68卷 392-393页

作者： qun li Haixin SUN Fu XIAO Yiming WANG Xinping GAO Bir BHANU School of Computer Science Nanjing University of Posts and Telecommunications Purple Mountain Laboratories Department of Electrical and Computer Engineering University of California at Riverside

Large language models (LLMs) have recently shown remarkable performance in a variety of natural language processing (NLP) *** further explore LLMs'reasoning abilities in solving complex problems,recent research [1-3]has investigated chain-of-thought (CoT) reasoning in complex multimodal scenarios,such as science question answering (ScienceQA) tasks [4],by fine-tuning multimodal models through human-annotated CoT ***,collected CoT rationales often miss the necessary rea-soning steps and specific expertise.

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Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang liang Yu-Gang Ma Xin-li Sheng qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation