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Chinese Journal of Aeronautics 2024年第9期37卷 506-520页

作者： jianyu wang Heng ZHANG Qiang MIAO College of Electrical Engineering Sichuan UniversityChengdu 610065China

Health monitoring of electro-mechanical actuator(EMA)is critical to ensure the security of *** is difficult or even impossible to collect enough labeled failure or degradation data from actual *** autoencoder based on reconstruction loss is a popular model that can carry out anomaly detection with only consideration of normal training data,while it fails to capture spatio-temporal information from multivariate time series signals of multiple monitoring *** mine the spatio-temporal information from multivariate time series signals,this paper proposes an attention graph stacked autoencoder for EMA anomaly ***,attention graph con-volution is introduced into autoencoder to convolve temporal information from neighbor features to current features based on different weight ***,stacked autoencoder is applied to mine spatial information from those new aggregated temporal ***,based on the bench-mark reconstruction loss of normal training data,different health thresholds calculated by several statistic indicators can carry out anomaly detection for new testing *** comparison with tra-ditional stacked autoencoder,the proposed model could obtain higher fault detection rate and lower false alarm rate in EMA anomaly detection experiment.

关键词： Anomaly detection Spatio-temporal informa-tion Multivariate time series signals Attention graph convolution Stacked autoencoder

Progress of Taiji-2 Project

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空间科学学报 2024年第4期44卷 674-676页

作者： LUO Ziren ZHANG Min wang jianyu WU Yueliang Taiji Laboratory for Gravitational Universe University of Chinese Academy of SciencesBeijing 100049 Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024 Institute of Mechanics Chinese Academy of SciencesBeijing 100190 International Center for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100190 Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083

Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 *** feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced here.

关键词： Gravitational wave Taiji program Taiji-2 project

Effects of nano-metal oxide additives on ignition and combustion properties of MICs-boron rich fuels

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Defence Technology（防务技术） 2024年第9期39卷 157-167页

作者： Liang Hu Danyang Liu Kun Yang Jianying Lu Chao Shi jianyu wang Xinhang Liu Lang Chen State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing100081China

Boron has been considered a promising powdered metal fuel for enhancing composite propellants'energy output due to its high energy ***,the high ignition temperature and low combustion efficiency limit the application of boron powder due to the high boiling point of the boron oxide *** research is ongoing to overcome these shortcomings,and one potential approach is to introduce a small quantity of metal oxide additives to promote the reaction of *** study prepared boron-rich fuels with 10 wt%of eight nano-metal oxide additives by mechanical ball *** effect of metal oxides on the thermo-oxidation,ignition,and combustion properties of boron powder was comprehensively studied by the thermogravimetric analysis(TG),the electrically heated filament setup(T-jump),and the laser-induced combustion *** experiments at 5 K/min found that Bi_(2)O_(3),MoO_(3),TiO_(2),Fe_(2)O_(3),and CuO can promote thermo-oxidation of *** to pure boron,Tonsetcan be reduced from 569℃to a minimum of 449℃(B/Bi_(2)O_(3)).Infrared temperature measurement in T-jump tests showed that when heated by an electric heating wire at rates from 1000 K/s to 25000 K/s,the ignition temperatures of B/Bi_(2)O_(3) are the lowest,even lower than the melting point of boron *** images and SEM for the products further showed that the high heating rate is beneficial to the rapid reaction of boron powder in the single-particle combustion ***(B/Bi_(2)O_(3),B/MoO_(3),and B/CuO)were mixed with the oxidant AP and ignited by laser to study the combustion *** results showed that B/CuO/AP has the largest flame area,the highest BO_(2) characteristic spectral intensity,and the largest burn rate for powder *** combine the advantages of CuO and Bi_(2)O_(3),binary metal oxide(CBO,mass ratio of 3:1)was prepared and the test results showed that CBO can very well improve both ignition and combustion properties of *** B/CBO/AP has the h

关键词： Boron-rich fuel Mechanical ball milling Electrically heated filament Laser-induced combustion

Allotetraploidization event of Coptis chinensis shared by all Ranunculales

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Horticultural Plant Journal 2024年第1期10卷 288-303页

作者： Yan Zhang Weina Ge Jia Teng Yanmei Yang jianyu wang Zijian Yu Jiaqi wang Qimeng Xiao Junxin Zhao Shaoqi Shen Yishan Feng Shoutong Bao Yu Li Yuxian Li Tianyu Lei Yuxin Pan Lan Zhang Jinpeng wang Department of Bioinformatics School of Life SciencesNorth China University of Science and TechnologyTangshanHebei 063000China School of Life Sciences North China University of Science and TechnologyTangshanHebei 063000China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of ScienceBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Coptis chinensis Franch.,also named Chinese goldthread is a member of Ranunculaceae in the order Ranunculales and represents an important lineage of early eudicots with traditional medicinal *** our study,by using syntenic analysis combined with phylogenomic analysis of *** and four other representative genomes from basal and core eudicots,we confirmed that the WGD event in *** was shared by Aquilegia coerulea and Papaver somniferum *** quickly occurred after Ranunculales diverged from other eudicots,likely a Ranunculales common tetraploidization(RCT).The synonymous nucleotide substitutions at synonymous sites distribution of syntenic blocks across these genomes showed that the evolutionary rate of the *** genome is faster than that of the *** genome by approximately 13.7%,possibly due to Papaveraceaes having an additional special tetraploidization event(PST).After Ks correction,the RCT dated to 115—130 million years ago(MYA),which was close to the divergence of Ranunculaceaes and Papaveraceaes approximately115.45—130.51 ***,we identified homologous genes related to polyploidization and speciation and constructed multiple sequence alignments with different reference ***,the event-related subgenomes in the basal genomes all showed genomic fractionation bias,suggesting a likely allopolyploid nature of the RCT,PST and T-Alpha and T-Beta events in Tetracentron *** addition,we detected that the sixteen P450 subfamilies were markedly expanded in the genomes of Ranunculales,and most of them were related to the RCT and PST *** constructed a new platform for Early Eudicot Comparative Genomic Research(http://***/***)to store more *** summary,our findings support the WGD of *** shared by Ranunculales,which is likely an allotetraploidization *** present effort offered new insights into the evolution of key polyploidization events and the genes related to second

关键词： Coptis chinensis Ranunculales Polyploidization Genomic fractionation P450 genes

A likely paleo-autotetraploidization event shaped the high conservation of Nyssaceae genome

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Horticultural Plant Journal 2024年第3期10卷 911-930页

作者： Yishan Feng Zhenyi wang Qimeng Xiao Jia Teng jianyu wang Zijian Yu Jiaqi wang Qiang Xu Yan Zhang Shaoqi Shen Shoutong Bao Yu Li Zimo Yan Yue Ding Zihan Liu Yuxian Li Tianyu Lei Min Yuan Xiu-Qing Li Jinpeng wang Department of Bioinformatics School of Life SciencesNorth China University of Science and TechnologyTangshanHebei 063000China Fredericton Research and Development Centre Agriculture and Agri-Food CanadaFrederictonNew Brunswick E3B 4Z7Canada State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of ScienceBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Scientific knowledge about the ancestral genome of core eudicot plant kingdom can potentially have profound impacts on both basic and applied research,including evolution,genetics,genomics,ecology,agriculture,forestry,and global *** investigate which plant conserves best the core eudicots common ancestor genome,we compared Arcto-Tertiary relict Nyssaceae and 30 other eudicot plant *** genomes of Davidia involucrata(a known living fossil),Camptotheca acuminata and Nyssa sinensis,one per existent genus of Nyssaceae,were performed comparative genomic *** found that Nyssaceae originated from a single Nyssaceae common tetraploidization event(NCT)-autotetraploidization 28-31 Mya after the core eudicot common hexaploidization(ECH).We identified Nyssaceae orthologous and paralogous genes,determined its chromosomal evolutionary trajectory,and reconstructed the Nyssaceae most recent ancestor *** genome contained the entire seven paleochromosomes and 17 ECH-generated eudicot common ancestor chromosomes and was the slowest in mutation among the analyzed 42 species of 31 plant *** both its high retention of paleochromosomes and its low mutation rate,*** provides the best case in conservation of the core eudicot paleogenome.

关键词： Nyssaceae Polyploidization Multigenome alignment Evolutionary rate Autotetraploidization Karyotype evolution

“对抗”还是“屈让”?——围岩挤压性大变形处治的基本理念

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现代隧道技术 2024年第3期61卷 1-7页

作者：王建宇中铁西南科学研究院有限公司成都611731

文章在对高地应力软弱围岩的挤压性机理进行探讨的基础上,着重论述了处治挤压性大变形的“屈让”理念以及与此相关的“恒阻释放”技术;同时,对无张拉锚杆和预应力锚索两种不同岩体锚固措施控制围岩挤压性变形的作用进行了分析和比较。此... 详细信息

文章在对高地应力软弱围岩的挤压性机理进行探讨的基础上,着重论述了处治挤压性大变形的“屈让”理念以及与此相关的“恒阻释放”技术;同时,对无张拉锚杆和预应力锚索两种不同岩体锚固措施控制围岩挤压性变形的作用进行了分析和比较。此外,文中还讨论了采用充填高变形材料的离壁式衬砌,缓解残余形变压力荷载,克服“等待”二次衬砌施作时机的困难。

关键词：软弱围岩挤压性大变形处治屈让恒阻释放离壁式衬砌

创新之树常青——《现代隧道技术》创刊60周年

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现代隧道技术 2024年第2期61卷 1-4页

作者：王建宇中铁西南科学研究院有限公司成都611731

时值《现代隧道技术》创刊60周年,本文回顾了60年来中国隧道工程技术进步,追赶现代化水平的历史,并展望未来,论述技术创新目标从“长隧道机械化快速施工”到“安全,优质和环境友好”的提升。

关键词：《现代隧道技术》创刊60周年中国隧道工程技术进步技术创新目标

SEVAR: a stereo event camera dataset for virtual and augmented reality

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 755-762页

作者： Yuda DONG Zetao CHEN Xin HE Lijun LI Zichao SHU Yinong CAOl Junchi FENG Shijie LIU Chunlai LI jianyu wang Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China University of Chinese Academy of Sciences Bejing 100049China Yongjiang Laboratory Ningbo 130021China

Event cameras,characterized by their low latency,large dynamic range,and extremely high temporal resolution,have recently received increasing *** features make them particularly well-suited for virtual/augmented reality(VR/AR)*** facilitate the development of three-dimensional(3D)perception and navigation algorithms in VR/AR applications using event cameras,we introduce the Stereo Event camera dataset for Virtual and Augmented Reality(SEVAR),which comprises a wide variety of head-mounted indoor sequences,including scenarios with rapid motion and a large dynamic range.

关键词： mounted dynamic camera

SiO_(2)-BNNSs杂化材料对磷酸盐复合涂层高温摩擦学性能的影响

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表面技术 2024年第15期53卷 34-44,76页

作者：魏文涛王全龙王剑宇王轶遥李啸江南大学机械工程学院江苏无锡214122 江南大学江苏省食品先进制造装备技术重点实验室江苏无锡214122 江南大学江苏省微纳增减材制造工程研究中心江苏无锡214122

目的通过在磷酸盐复合涂层中添加二氧化硅杂化氮化硼纳米片材料(SiO_(2)-BNNSs)来提升磷酸盐复合涂层的硬度和耐高温磨损性能。方法以正硅酸四乙酯(TEOS)为硅源,利用溶胶凝胶法制备SiO_(2)-BNNSs杂化材料,并作为纳米增强相加入到涂层中... 详细信息

目的通过在磷酸盐复合涂层中添加二氧化硅杂化氮化硼纳米片材料(SiO_(2)-BNNSs)来提升磷酸盐复合涂层的硬度和耐高温磨损性能。方法以正硅酸四乙酯(TEOS)为硅源,利用溶胶凝胶法制备SiO_(2)-BNNSs杂化材料,并作为纳米增强相加入到涂层中。通过X射线光电子能谱(XPS)、场发射扫描电子显微镜(FE-SEM)和透射电子显微镜(TEM)对SiO_(2)-BNNSs杂化材料的化学组成和微观形貌进行表征。另外,采用喷涂法制备不同含量BNNSs和SiO_(2)-BNNSs的磷酸盐复合涂层,通过高温摩擦磨损试验探究涂层的摩擦磨损行为,对涂层磨痕形貌进行表征,并探讨涂层在高温条件下的磨损机理。结果XPS、SEM和TEM的分析结果表明,SiO_(2)成功修饰在BNNSs表面。SiO_(2)-BNNSs磷酸盐涂层相比零含量BNNSs涂层和纯BNNSs涂层表现得更加均匀致密,400℃条件下,质量分数为0.4%的SiO_(2)-BNNSs涂层硬度高达261.2HV。高温摩擦试验表明,BNNSs和SiO_(2)-BNNSs的加入,可以减轻涂层的磨损现象。同时,温度越高,涂层的耐磨损性能越好,400℃条件下,0.4%SiO_(2)-BNNSs涂层的摩擦因数和磨损率分别为0.48和66.24×10–6mm^(3)/(N·m),耐高温磨损性能表现为最佳。结论SiO_(2)-BNNSs杂化材料的添加可以明显提升磷酸盐复合涂层的耐高温磨损性能。

关键词：氮化硼纳米片二氧化硅杂化材料磷酸盐复合涂层耐高温磨损性能

DS-TransFusion:基于改进Swin Transformer的视网膜血管自动分割

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工程科学学报 2024年第10期46卷 1889-1898页

作者：杨本臣王建宇金海波辽宁工程技术大学软件学院葫芦岛125105

视网膜血管的准确分割在辅助筛查各种疾病方面具有重大意义.然而,当前流行的模型仍存在细小血管的分割不清晰,以及眼底血管分支末端与背景的对比度较低等问题.针对这些问题,本文提出了一种全新的视网膜血管分割模型,命名为Dual Swin Tra... 详细信息

视网膜血管的准确分割在辅助筛查各种疾病方面具有重大意义.然而,当前流行的模型仍存在细小血管的分割不清晰,以及眼底血管分支末端与背景的对比度较低等问题.针对这些问题,本文提出了一种全新的视网膜血管分割模型,命名为Dual Swin Transformer Fusion(DS-TransFusion).首先,DS-TransFusion采用基于Swin Transformer的双尺度编码器子网络,以提取视网膜血管的粗粒度和细粒度特征.其次,在跳跃连接处引入了Transformer交互融合注意力(TIFA)模块,用于丰富跨视图上下文建模和语义依赖,同时捕获来自不同图像视图的数据之间的长期相关性.最后,在编码器和解码器之间,DS-TransFusion采用了多尺度注意力(MA),用于收集多尺度特征表示的全局对应关系,进一步优化模型的分割效果.实验结果表明,DS-TransFusion在公共数据集STARE、CHASEDB1和DRIVE上表现出色,准确率分别达到了96.50%、97.22%和97.80%,灵敏度达到84.10%、84.55%和83.17%.实验表明DS-TransFusion能有效提高视网膜血管分割的精度,准确分割出细小血管.对视网膜血管分割的准确度、灵敏度和特异性都有大幅提高,与现有的SOTA方法相比具有更好的分割性能.

关键词：视网膜血管分割眼底图像多尺度注意力特征融合 Swin Transformer