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跨走滑断层大跨度桁架悬索桥地震响应分析

铁道标准设计 2024年第7期68卷 92-100页

作者：邹作家郑史雄丁自豪贾宏宇余琦程维西南交通大学土木工程学院成都610031

跨越断层的长大跨度桥梁难免会受到断层错动作用,为探究跨走滑断层地震动参数对大跨度悬索桥地震响应的影响,以某主跨为538 m的钢桁架悬索桥为例,利用ABAQUS建立考虑桩-土相互作用(“m”法)的全桥有限元模型。通过叠加人工低频地震成分... 详细信息

跨越断层的长大跨度桥梁难免会受到断层错动作用,为探究跨走滑断层地震动参数对大跨度悬索桥地震响应的影响,以某主跨为538 m的钢桁架悬索桥为例,利用ABAQUS建立考虑桩-土相互作用(“m”法)的全桥有限元模型。通过叠加人工低频地震成分和实际高频地震成分,合成了跨走滑断层地震动,采用非一致激励位移时程法,重点分析永久位移、脉冲周期和跨断层角度对大跨度悬索桥的动力响应影响。结果表明:随着永久位移增大,桥塔动力响应呈不同幅度的增长,特别是横桥向位移、剪力,以及顺桥向弯矩增幅比较明显,分别增大97%、88%和95%,且剪力的增大加剧了桥塔发生剪切破坏的风险;随着脉冲周期减小,桥塔沿顺桥向和横桥向的动力响应增幅差距较大,当脉冲周期小于4 s时,桥塔横桥向位移、剪力,以及顺桥向弯矩相较于另一方向增幅更为明显,其增幅分别为492.5%、170%和189.2%;跨断层角度对桥塔的动力响应影响较大,且沿顺桥向和横桥向的响应变化趋势相反,跨断层角度为90°时,桥塔横桥向位移、剪力取得最大值,而弯矩取得最小值,且桥塔动力响应均在合理范围内,为最佳跨越角度。

关键词：大跨度悬索桥走滑断层地震动合成永久位移脉冲周期跨断层角度地震响应

Data-Driven Human-Robot Interaction Without Velocity Measurement Using Off-Policy Reinforcement Learning

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IEEE/CAA Journal of Automatica Sinica 2022年第1期9卷 47-63页

作者： Yongliang Yang zihao ding Rui Wang Hamidreza Modares Donald C.Wunsch Key Laboratory of Knowledge Automation for Industrial Processes Ministry of Education School of Automation&Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China School of Automation Beijng Institute TechnologyBeijing 100081China State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Mechanical Engineering Department Michigan State UniversityEast LansingMI 48824 USA Department of Electrical&Computer Engineering Missouri University of Science&TechnologyRollaMO 65401 USA

In this paper,we present a novel data-driven design method for the human-robot interaction(HRI)system,where a given task is achieved by cooperation between the human and the *** presented HRI controller design is a two-level control design approach consisting of a task-oriented performance optimization design and a plant-oriented impedance controller *** task-oriented design minimizes the human effort and guarantees the perfect task tracking in the outer-loop,while the plant-oriented achieves the desired impedance from the human to the robot manipulator end-effector in the ***-driven reinforcement learning techniques are used for performance optimization in the outer-loop to assign the optimal impedance *** the inner-loop,a velocity-free filter is designed to avoid the requirement of end-effector velocity *** this basis,an adaptive controller is designed to achieve the desired impedance of the robot manipulator in the task *** simulation and experiment of a robot manipulator are conducted to verify the efficacy of the presented HRI design framework.

关键词： Adaptive impedance control data-driven method human-robot interaction(HRI) reinforcement learning velocity-free

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基于耐震时程法的大跨度钢桁拱桥易损性分析

铁道标准设计 2024年第6期68卷 106-113页

作者：余琦郑史雄丁自豪陈志强邹作家贾宏宇西南交通大学土木工程学院成都610031 成都大学建筑与土木工程学院成都610106

为克服复杂桥梁结构在地震易损性评估时需要进行大量非线性时程分析的不足,提出一种基于耐震时程法(ETM)的易损性分析方法用于桥梁结构易损性的快速评估。首先,基于ETM合成了若干条耐震时程曲线(ETA),将其与概率地震需求模型相结合。随... 详细信息

为克服复杂桥梁结构在地震易损性评估时需要进行大量非线性时程分析的不足,提出一种基于耐震时程法(ETM)的易损性分析方法用于桥梁结构易损性的快速评估。首先,基于ETM合成了若干条耐震时程曲线(ETA),将其与概率地震需求模型相结合。随后,考虑桥梁模型的不确定性,借助OpenSEES建立一座大跨度上承式钢桁拱桥的有限元模型样本库,并分别使用ETM和增量动力分析(IDA)法对其中的桥梁模型进行时程分析并得到典型构件的易损性曲线,将二者结果进行对比以验证ETM的适用性。最后,利用验证后的方法分析该桥各构件纵向地震下的易损性。结果表明:ETM与IDA所得结果的相对误差基本控制在5%以内,说明基于耐震时程的易损性方法可有效兼顾分析效率和计算精度;在纵向地震作用下,上承式钢桁拱桥的引桥墩和交界墩在50%中等损伤概率下的地震动强度指标仅为0.597g和0.972g,远小于其他构件,说明混凝土桥墩为最易损构件;拱肋和立柱在地震作用下发生破坏的概率较小,但拱顶和拱脚相对薄弱;设置固定支座的短立柱在纵向地震作用下易发生损伤,可通过改变拱上立柱的支座布置形式进行优化。

关键词：大跨度拱桥地震易损性耐震时程法概率地震需求模型不确定性增量动力分析

Heat management technology for solid-state high voltage and high repetitive pulse generators:Towards better effects and reliability

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High Voltage 2024年第1期9卷 2-21页

作者： Yanan Wang Linyuan Ren zihao Yang Saikang Shen Zichen Deng Qi Yuan Weidong ding Zhenjie ding School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina School of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'anChina

Solid-state high voltage high repetitive pulse generators have a broad prospect in various *** high power and high-frequency operation of the pulse generator suffer from the massive heat dissipation problem,which limits the improvement of the output parameters and even affects the *** article focuses on heat management technology for high voltage high repetitive pulse ***,the typical circuit topology of the high repetitive pulse generators was *** the perspective of different application requirements,the demands of the heat management design were ***,the heat generation characteristics and difficulties of solid-state high voltage high repetitive pulse generators were ***,the different stateof-art cooling techniques were reviewed,and their applicability and limitations for the high voltage high repetitive generators were ***,a flow chart for heat management design was given.

关键词： pulse state high

Zinc oxide nanoparticles inhibit osteosarcoma metastasis by downregulatingβ-catenin via HIF-1α/BNIP3/LC3B-mediated mitophagy pathway

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生物活性材料(英文) 2023年第1期19卷 690-702页

作者： Guanping He Jing-Jun Nie Xiao Liu zihao ding Peng Luo Yu Liu Bo-Wen Zhang Renxian Wang Xiaoguang Liu Yong Hai Da-Fu Chen Department of Orthopedics Beijing Chao-Yang HospitalCapital Medical UniversityBeijing100020China Laboratory of Bone Tissue Engineering Beijing Laboratory of Biomedical MaterialsBeijing Research Institute of Traumatology and OrthopaedicsBeijing Jishuitan HospitalBeijing100035China Department of Orthopedics Peking University Third HospitalBeijing100191China

Osteosarcoma(OS)therapy faces many challenges,especially the poor survival rate once metastasis ***,it is crucial to explore new OS treatment strategies that can efficiently inhibit OS *** nanoparticles such as zinc oxide nanoparticles(ZnO NPs)can efficiently inhibit OS growth,however,the effect and mechanisms of them on tumor metastasis are still not *** this study,we firstly prepared well-dispersed ZnO NPs and proved that ZnO NPs can inhibit OS metastasis-related malignant behaviors including migration,invasion,and epithelial-mesenchymal transition(EMT).RNA-Seqs found that differentially expressed genes(DEGs)in ZnO NP-treated OS cells were enriched in wingless/integrated(Wnt)and hypoxia-inducible factor-1(HIF-1)signaling *** further proved that Zn^(2+)released from ZnO NPs induced downregulation ofβ-catenin expression via HIF-1α/BNIP3/LC3B-mediated mitophagy *** NPs combined with ICG-001,aβ-catenin inhibitor,showed a synergistic inhibitory effect on OS lung metastasis and a longer survival *** addition,tissue microarray(TMA)of OS patients also detected much higherβ-catenin expression which indicated the role ofβ-catenin in OS *** summary,our current study not only proved that ZnO NPs can inhibit OS metastasis by degradingβ-catenin in HIF-1α/BNIP3/LC3B-mediated mitophagy pathway,but also provided a far-reaching potential of ZnO NPs in clinical OS treatment with metastasis.

关键词： Zinc oxide nanoparticle HIF-1α/BNIP3/LC3B-mediated mitophagy pathway Metastasis Osteosarcoma

考虑温度影响的半刚性基层沥青路面裂缝处结构强度变化规律分析

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城市道桥与防洪 2024年第8期 237-240页

作者：樊云龙祝争艳卜勇丁子豪金光来臧国帅朱奇江苏高速公路工程养护技术有限公司江苏南京210000 江苏中路工程技术研究院有限公司江苏南京210000

裂缝病害是当前高速公路沥青路面出现的主要病害类型之一,裂缝对路面的结构强度产生一定程度的削弱。根据弯沉盆数据可以反演各结构层模量,评估结构强度。选取宁杭高速开展针对裂缝的弯沉检测,对裂缝处结构强度变化规律和受温度影响情... 详细信息

裂缝病害是当前高速公路沥青路面出现的主要病害类型之一,裂缝对路面的结构强度产生一定程度的削弱。根据弯沉盆数据可以反演各结构层模量,评估结构强度。选取宁杭高速开展针对裂缝的弯沉检测,对裂缝处结构强度变化规律和受温度影响情况进行分析。结果表明:裂缝对弯沉影响显著,裂缝处弯沉约是完好处弯沉的2.17倍,裂缝处基层和底基层模量衰减程度较为严重,基层衰减程度为81.49%,底基层衰减程度为77.45%;完好处的面层材料模量相较于裂缝处受温度影响较大,变化幅度可达到10.3倍,基层、底基层和路基的模量随温度变化并不明显。

关键词：道路工程裂缝结构强度弯沉检测温度模量反演

锈蚀RC柱的概率抗弯承载力模型与概率校准分析

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应用基础与工程科学学报 2022年第6期30卷 1468-1479页

作者：丁自豪桑卜久卢朝辉余波广西大学土木建筑工程学院广西南宁530004 西南交通大学土木工程学院四川成都610031 北京工业大学建筑工程学院北京100124

结合理论分析和209组试验数据,分别研究建立了锈蚀钢筋混凝土(RC)柱在大、小偏心受压条件下的概率抗弯承载力模型与概率校准分析方法.根据内力平衡条件,考虑锈蚀因素对钢筋和混凝土的材料性能及其二者粘结性能的影响,通过引入考虑不确... 详细信息

结合理论分析和209组试验数据,分别研究建立了锈蚀钢筋混凝土(RC)柱在大、小偏心受压条件下的概率抗弯承载力模型与概率校准分析方法.根据内力平衡条件,考虑锈蚀因素对钢筋和混凝土的材料性能及其二者粘结性能的影响,通过引入考虑不确定性的概率模型参数和模型误差,分别建立了锈蚀RC柱在大、小偏心受压条件下的概率抗弯承载力计算表达式,并利用Bayesian理论和马尔科夫链蒙特卡罗法确定了概率模型参数的后验信息,进而结合概率密度函数、置信区间和置信水平,校准了传统确定性抗弯承载力模型的计算精度.分析表明,概率抗弯承载力模型的计算精度较高,可以合理描述抗弯承载力所具有的随机性;对于大偏心受压锈蚀RC柱,现有模型的计算精度相对较高,而对于小偏心受压锈蚀RC柱,现有模型的计算精度较低、离散性较大.

关键词：钢筋混凝土柱锈蚀抗弯承载力概率校准大偏心受压小偏心受压

The lysine methyltransferase SMYD2 facilitates neointimal hyperplasia by regulating the HDAC3-SRF axis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 712-728页

作者： Xiaoxuan Zhong Xiang Wei Yan Xu Xuehai Zhu Bo Huo Xian Guo Gaoke Feng zihao Zhang Xin Feng Zemin Fang Yuxuan Luo Xin Yi ding-Sheng Jiang Division of Cardiovascular Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Key Laboratory of Organ Transplantation Ministry of EducationNHC Key Laboratory of Organ TransplantationChinese Academy of Medical SciencesWuhan 430030China School of Life Science and Technology Key Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjing 210096China Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060China

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart ***,we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum-and PDGF-BB-induced vascular smooth muscle cells(VSMCs),and in tissues of carotid artery injury-induced neointimal ***2 overexpression in VSMCs(Smyd2-vTg)facilitates,but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in *** sequencing revealed that SMYD2 knockdown represses the expression of serum response factor(SRF)target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC ***3 directly interacts with and deacetylates SRF,which enhances SRF transcriptional activity in ***,SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its ***966,a specific inhibitor of HDAC3,not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs,but also inhibits carotid artery injury-induced neointima formation in ***3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent *** results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

关键词： Neointimaformation Histonemethylation Histoneacetylation SRFacetylation SMYD2 HDAC3 LLY-507 RGFP966

基于部分分层抽样的高墩桥梁随机地震响应分析

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振动与冲击 2022年第7期41卷 214-222,234页

作者：陈志强郑史雄丁自豪张金西南交通大学土木工程学院成都610031 成都理工大学环境与土木学院成都610059

为了表征桥梁结构不确定性和随机参数相关性对桥梁结构抗震性能的影响,从概率角度对桥梁进行抗震性能分析,基于部分分层抽样原理建立了时-频非平稳地震作用下桥梁非线性随机地震响应分析方法。基于地震动演化功率谱,采用谱表示方法生成... 详细信息

为了表征桥梁结构不确定性和随机参数相关性对桥梁结构抗震性能的影响,从概率角度对桥梁进行抗震性能分析,基于部分分层抽样原理建立了时-频非平稳地震作用下桥梁非线性随机地震响应分析方法。基于地震动演化功率谱,采用谱表示方法生成非平稳地震动样本,并采用基于正交函数的思想对谱表示方法中的随机变量进行模拟,通过两个基本随机变量表征地震动的不确定性;采用基于数论的部分分层抽样方法对地震动-结构随机变量抽样,从而对桥梁非线性随机地震响应进行模拟,减小桥梁随机地震响应分析中的抽样方差;以一座实际高墩连续刚构桥为数值算例,对其进行了非线性随机地震响应分析,详细研究了桥梁结构不确定性和随机参数相关性对其地震可靠度的影响。研究结果表明:随机地震作用下,桥梁随机地震响应是典型的零均值非平稳随机过程,从地震动开始到结束,桥梁结构地震响应概率密度曲线存在由窄边宽,再由宽变窄的演化过程;随机地震作用下,桥梁结构关键响应的平均峰值因子存在一定差异,其通常在1.8~2.2变化;桥梁结构不确定性和随机参数相关性对高墩桥梁地震响应极值分布和地震可靠度的影响较为显著,忽略桥梁结构的不确定性和随机参数相关性将高估桥梁结构的地震可靠度。

关键词：非平稳随机地震响应极值分布地震可靠度部分分层抽样