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结构全场工作模态分析的计算机视觉测振方法

振动工程学报 2024年第2期37卷 226-236页

作者：王路倩王振宇王兴中山大学·深圳航空航天学院广东深圳518107 深圳市智能微小卫星星座技术与应用重点实验室广东深圳518107

介绍了一种基于计算机视觉的结构模态参数辨识方法,对于连续、长时间的采样视频,该方法通过设置局部“虚拟”测点、放大视频切片的处理方式,保证了测量结果的精度和分辨率,同时显著提高了数据处理效率。该方法具体步骤包括:拍摄被测结... 详细信息

介绍了一种基于计算机视觉的结构模态参数辨识方法,对于连续、长时间的采样视频,该方法通过设置局部“虚拟”测点、放大视频切片的处理方式,保证了测量结果的精度和分辨率,同时显著提高了数据处理效率。该方法具体步骤包括:拍摄被测结构在外激励下响应历程的一段视频;通过图像边缘检测算法在结构边缘处设置若干“虚拟”测点;通过光流法提取测点的表观运动响应,并利用随机子空间法辨识结构的模态参数;依次截取与每一阶模态对应的整周期运动视频,通过运动放大算法获得结构的全场工作模态振型。开展了模型飞机的单频振动试验,结果表明视觉测振的频率误差小于频率分辨率。开展了悬臂梁的模态分析试验,利用相机和激光多普勒测振仪同时进行动力学响应测量,结果显示提出的视觉方法与激光多普勒测振仪对悬臂梁结构前五阶模态频率的测量误差不超过0.35%,阻尼比的测量误差不超过14.6%,两者振型的MAC值高于94%,测量结果基本吻合。

关键词：视觉测振法光流法运动放大工作模态分析

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心血管成纤维细胞显像的现状和展望

首都医科大学学报 2024年第1期45卷 46-51页

作者：李丽娜杨敏福首都医科大学附属北京朝阳医院核医学科北京100020

心肌纤维化是众多心血管疾病共同的基础病理改变,与心脏不良预后密切相关。目前临床上评价心肌纤维化的技术存在有创、特异性欠佳、无法早期诊断等不足。近年来,靶向活化成纤维细胞的核素显像因其在检测心肌纤维化以及在评估疾病进展和... 详细信息

心肌纤维化是众多心血管疾病共同的基础病理改变,与心脏不良预后密切相关。目前临床上评价心肌纤维化的技术存在有创、特异性欠佳、无法早期诊断等不足。近年来,靶向活化成纤维细胞的核素显像因其在检测心肌纤维化以及在评估疾病进展和治疗反应方面的潜力而受到人们的关注。本文结合现有研究,重点介绍其应用现状、优势和局限性,探讨其在心血管疾病中的前景,旨在为进一步推动靶向活化成纤维细胞的核素显像在心血管疾病中的应用提供参考和启示。

关键词：心血管疾病成纤维细胞活化蛋白抑制剂心肌纤维化分子显像

Accelerating collaborative innovation in hydrological, engineering, and environmental fields

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Journal of Groundwater Science and Engineering 2024年第1期12卷 1-3页

作者： Min wang Vice Minister of the former Ministry of Land and Resources of the PRC BeijingChina

To fulfill the new requirements of geological work in the modern era and explore the latest advancements in hydrogeology,ecological geology,and geothermal geology that contribute to the development of an ecological civilization and effective natural resource management,the academic symposium on"Synergetic Innovation and Green Development in Water-Heat-Ecology"took place from October 14th to 15th,2023.Organized by the China Geological Society and collaboratively hosted by the Hydrogeology Professional Committee,Ecological Geology Professional Committee,and Geothermal Professional Committee,the event featured an insightful speech by Mr.wang Min,former Deputy Minister of the Ministry of Land and Resources of the PRC.His perspectives offer valuable insights for current geological endeavours,and we have compiled the content of this speech into this article.

关键词： geology insight ecological

Genetic analysis and candidate gene identification of salt tolerancerelated traits in maize

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Journal of Integrative Agriculture 2024年第7期23卷 2196-2210页

作者： Hui Fang Xiuyi Fu Hanqiu Ge Mengxue Jia Jie Ji Yizhou Zhao Zijian Qu Ziqian Cui Aixia Zhang Yuandong wang Ping Li Baohua wang Scientific Observing and Experimental Station of Maize in Plain Area of Southern Region Ministry of Agriculture and Rural Affairs/School of Life SciencesNantong UniversityNantong 226019China Maize Research Institute Beijing Academy of Agriculture and Forestry Sciences(BAAFS)Beijing 100097China

Soil salinization poses a threat to maize production worldwide,but the genetic mechanism of salt tolerance in maize is not well understood.Therefore,identifying the genetic components underlying salt tolerance in maize is of great importance.In the current study,a teosinte-maize BC2F7 population was used to investigate the genetic basis of 21 salt tolerance-related traits.In total,125 QTLs were detected using a high-density genetic bin map,with one to five QTLs explaining 6.05–32.02%of the phenotypic variation for each trait.The total phenotypic variation explained(PVE)by all detected QTLs ranged from 6.84 to 63.88%for each trait.Of all 125 QTLs,only three were major QTLs distributed in two genomic regions on chromosome 6,which were involved in three salt tolerance-related traits.In addition,10 pairs of epistatic QTLs with additive effects were detected for eight traits,explaining 0.9 to 4.44%of the phenotypic variation.Furthermore,18 QTL hotspots affecting 3–7 traits were identified.In one hotspot(L5),a gene cluster consisting of four genes(ZmNSA1,SAG6,ZmCLCg,and ZmHKT1;2)was found,suggesting the involvement of multiple pleiotropic genes.Finally,two important candidate genes,Zm00001d002090 and Zm00001d002391,were found to be associated with salt tolerance-related traits by a combination of linkage and marker-trait association analyses.Zm00001d002090 encodes a calcium-dependent lipid-binding(CaLB domain)family protein,which may function as a Ca^(2+)sensor for transmitting the salt stress signal downstream,while Zm00001d002391 encodes a ubiquitin-specific protease belonging to the C19-related subfamily.Our findings provide valuable insights into the genetic basis of salt tolerance-related traits in maize and a theoretical foundation for breeders to develop enhanced salt-tolerant maize varieties.

关键词： maize salt tolerance-related traits QTL mapping region-based association analysis

Effects of Dietary Changes on the Gut Microbiota of Cynops orientalis

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Asian Herpetological Research 2024年第2期15卷 63-72页

作者： Yuting wang Yuning XIE Siyu WU Wenwen ZHANG Xiner CHENG Zixuan LI Fangfei HAN Jiayi SHI Yingying SHI Zhirong HE Chunna ZHANG Yixin JIANG Na ZHAO Jiaqi LI Supen wang College of Life Sciences Anhui Normal UniversityWuhu 241000AnhuiChina Nanjing Institute of Environmental Sciences Ministry of Ecology and Environment of ChinaNanjing 210042JiangsuChina School of Ecology and Environment Anhui Normal UniversityWuhu 241002AnhuiChina Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China

The gut microbiota plays a pivotal role in the maintenance of health for amphibians,and it has been fully recognized,but the effectiveness of various influencing factors has not yet been fully clarified.Although this association should be considered while the amphibian order Caudata is facing a severe situation of population decline and extinction,there is little understanding of the association between diets and the diversity of gut microbiota in the amphibian order Caudata.Here,we conducted an extensive analysis of the gut microbiota of Cynops orientalis fed different diets using functional prediction and 16S rRNA amplicon sequencing techniques.First,we found that wild individuals had greater gut microbial diversity and richness in comparison to captive individuals.Second,we identified the bacterial taxa associated with diets and observed differences in the relative abundance of gut microbiota among people on various diets.Finally,we have a predictive comprehension of the selection and adaptative significance of shared core ASVs in the gut microbiota in maintaining the healthy survival of C.orientalis in a large-scale spatiotemporal map.Our study emphasizes how diets alter the gut microbiota of Caudata and offers fresh perspectives on the conservation and captive management of species in Caudata.

关键词： 16S rRNA Caudata core microbiota diet gut microbiota

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基于BFGS方法的列车速度预测控制研究

铁道科学与工程学报 2024年第2期21卷 522-532页

作者：王玺邢科家王健王芃中国铁道科学研究院研究生部北京100081 中国铁道科学研究院集团有限公司通信信号研究所北京100081 国家铁路智能运输系统工程技术研究中心北京100081

列车速度控制是轨道交通发展领域的重要基础问题。面向真实列车速度控制应用场景的列车动力学模型及其控制器设计更具挑战性。一方面,传统基于反馈的无模型控制策略存在收敛速度慢、参数要求高、环境变化敏感等问题,目前难以从优化角度... 详细信息

列车速度控制是轨道交通发展领域的重要基础问题。面向真实列车速度控制应用场景的列车动力学模型及其控制器设计更具挑战性。一方面,传统基于反馈的无模型控制策略存在收敛速度慢、参数要求高、环境变化敏感等问题,目前难以从优化角度设计控制器且应对复杂系统的约束。另一方面,传统的列车单质点动力学模型很难解决高速列车运行过程中的非线性特性。针对上述瓶颈,首先对列车各节车厢进行受力分析,且考虑车厢间的安全距离,将相对位置和相对速度作为可变状态构建列车多质点模型。然后采用模型预测控制策略,综合考虑列车速度控制的非线性成本函数,处理列车运行过程中的复杂约束,预测控制系统的未来动态行为。然后,针对列车预测控制中的复杂动态约束非线性优化问题,设计对数障碍函数处理不等式约束,进而从拟牛顿法角度设计一种具有稳定收敛性的基于BFGS方法的列车速度预测控制算法,完成列车速度的精准跟踪控制。最后,以国内某线站间列车运行数据为例,与其他先进控制方法进行对比实验,以验证所提出的BFGS列车速度预测控制算法的优越性能。实验结果表明,本文所设计的基于BFGS方法的列车速度预测控制算法能够有效地减小列车速度跟踪误差和位移误差,提升列车速度跟踪精度,有利于保障列车的安全、准点、高效、平稳运行,为轨道交通列车速度控制技术发展提供新思路。

关键词：多质点模型模型预测控制 BFGS 列车速度控制

Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN Huan-zhao CHANG Yuan-jiang SUN Bao-jiang wang Kang CHEN Guo-ming LI Hao DAI Yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production well.However,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during production.To fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate decomposition.Based on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is developed.The analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability deterioration.The higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even instability.This work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration

Experimental observation of multiple topological nodal structure in LaSb_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 138-145页

作者： Yuxi Qiao Fuyi wang Huaiqiang wang Zicheng Tao Zhicheng Jiang Zhengtai Liu Soohyun Cho Fayuan Zhang Qingkai Meng Wei Xia Yichen Yang Zhe Huang Jishan Liu Zhonghao Liu Zengwei Zhu Shan Qiao Yanfeng Guo Haijun Zhang Dawei Shen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China National Synchrotron Radiation Laboratory and School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China School of Physics and Technology Nanjing Normal UniversityNanjing 210023China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and TechnologyWuhan 430074China ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 201210China Institute of High-Pressure Physics School of Physical Science and Technology Ningbo UniversityNingbo 315211China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Unconventional fermions in the immensely studied topological semimetals are the source for rich exotic topological properties.Here,using symmetry analysis and first-principles calculations,we propose the coexistence of multiple topological nodal structure in LaSb_(2),including topological nodal surfaces,nodal lines and in particular eightfold degenerate nodal points,which have been scarcely observed in a single material.Further,utilizing angle-resolved photoemission spectroscopy,we confirm the existence of nodal surfaces and eightfold degenerate nodal points in LaSb_(2).The intriguing multiple topological nodal structure might play a crucial role in giving rise to the large linear magnetoresistance.Our work renews the insights into the exotic topological phenomena in LaSb_(2).

关键词： eightfold degenerate points multiple topological nodal structure angle-resolved photoemission spectroscopy linear unsaturated magnetoresistance

Targeted G-to-T base editing for generation of novel herbicide-resistance gene alleles in rice

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Journal of Integrative Plant Biology 2024年第6期66卷 1048-1051页

作者： Yifu Tian Xinbo Li Jiyong Xie Zai Zheng Rundong Shen Xuesong Cao Mugui wang Chao Dong Jian-Kang Zhu Ministry of Agriculture and Rural Affairs Key Laboratory of Gene Editing Technologies (Hainan) Institute of Crop Sciences and National Nanfan Research Institute Chinese Academy of Agricultural Sciences Hainan Seed Industry Laboratory Shanghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant Sciences The Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Advanced Biotechnology and School of Medicine Southern University of Science and Technology

Deaminase-based cytosine base editors (CBEs) and adenine base editors (ABEs) induce C-to-T and A-to-G transitions, respectively, enabling single-nucleotide variants(SNVs) in plants for research and crop enhancement (Li et al.,2023a). The C-to-G base editors (CGBEs) and A-to-Y base editors (AYBEs), developed by incorporating glycosylases with CBEs and ABEs, expand the repertoire of base editing products, allowing C-to-T/G and A-to-T/G transversions in plants (Li et al., 2023b, 2023c; Sretenovic et a., 2021;

关键词： TOLERANCE