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International Journal of Extreme Manufacturing 2024年第2期6卷 325-376页

作者： Guohua Zhang Ming Huang Gangli Chen jiasheng li Yang liu Jianguo He Yueqing Zheng Siwei Tang Hailong Cui Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyangSichuan 621999People’s Republic of China

Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power *** all these applications,the equipment must deliver extreme working performances such as ultraprecise movement,ultrahigh rotation speed,ultraheavy bearing loads,ultrahigh environmental temperatures,strong radiation resistance,and high vacuum operation,which have challenged the design and optimization of reliable fluid lubricated *** of any related bottlenecks will promote the development course of high-end *** promote the advancement of high-end equipment,this paper reviews the design and optimization of fluid lubricated bearings operated at typical extreme working performances,targeting the realization of extreme working performances,current challenges and solutions,underlying deficiencies,and promising developmental *** paper can guide the selection of suitable fluid lubricated bearings and optimize their structures to meet their required working performances.

关键词： fluid lubricated bearings structural design performance optimization extreme working performances

New perspectives on the genetic structure of dotted gizzard shad(Konosirus punctatus)based on RAD-seq

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Marine life Science & Technology 2024年第1期6卷 50-67页

作者： Ying Peng Yifan liu jiasheng li Kun Zhang Xun Jin Sixu Zheng Yunpeng Wang Zhenming Lu liqin liu li Gong Bingjian liu National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization Zhejiang Ocean UniversityZhoushan 316022China National Engineering Research Center for Facilitated Marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean UniversityZhoushan 316022China

To maintain,develop and rationally utilize marine organisms,understanding their genetic structure and habitat adaptation pattern is *** punctatus,which is a commercial fish species inhabiting the Indo-west Pacific Ocean,has shown an obvious annual global capture and aquaculture production decline due to climate changes and human *** the present study,restriction-site associated DNA sequencing(RAD-seq)was used to describe its genome-wide single nucleotide polymorphisms panel(SNPs).Among 146 individuals collected at nine locations scattered in China,Korea and Japan,a set of 632,090 SNPs were *** genetic analysis showed that *** individuals were divided into two significant genetic ***,potential genetic differentiation between northern and southern population of *** was *** results indicated that gene flow existed among sampling locations of ***,especially from southern Japan to ***,candidate genes associated with habitat adaptations of *** were identified,which are involved in diverse physiological processes of *** including growth and development(e.g.,KIDINS220,PAN3),substance metabolism(e.g.,PGM5)and immune response(e.g.,VAV3,CCT7,HSPA12B).Our findings may aid in understanding the possible mechanisms for the population genetic structure and local adaptation of ***,which is beneficial to establish the management and conservation units of ***,guiding the rational use of resources,with reference significance for a profound understanding of the adaptative mechanisms of other marine organisms to the environment.

关键词： Population structure Konosirus punctatus SNP RAD-seq Local adaptation

基于GMM的压电驱动器磁滞特性建模及高精度抗扰跟踪控制

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中国科学：技术科学 2024年第3期54卷 443-458页

作者：黄鹏升李加胜丁烨上海交通大学机械与动力工程学院上海200240

包含压电驱动器的微定位平台可以用于减小飞切加工中的低频误差.本文针对该平台中的压电驱动单元,提出了一种新的系统建模方法,并基于此建立了完整的高性能抗扰跟踪控制策略.首先,利用高斯混合模型(Gaussian mixture model,GMM)对压电... 详细信息

包含压电驱动器的微定位平台可以用于减小飞切加工中的低频误差.本文针对该平台中的压电驱动单元,提出了一种新的系统建模方法,并基于此建立了完整的高性能抗扰跟踪控制策略.首先,利用高斯混合模型(Gaussian mixture model,GMM)对压电驱动器固有的磁滞特性建模,并根据该模型进行前馈补偿,以消除磁滞非线性对控制精度的影响.其次,建立扩张状态观测器,对所有外部扰动及未建模误差进行观测与补偿,以提高系统的抗扰能力.为了进一步提高系统的跟踪精度与控制带宽,建立状态反馈与零相跟踪前馈控制策略,以优化闭环系统特性.实验结果验证了基于所提磁滞模型建立的抗扰跟踪控制方法的有效性.在0~50 Hz输入信号频率范围内,在给定的测试集内该控制策略下的系统跟踪误差小于2.2%,能够满足目标控制带宽下的高精度跟踪要求.

关键词：压电驱动器磁滞非线性高斯混合模型扩张状态观测器抗扰控制

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末次冰盛期以来基于孢粉定量重建的植物多样性变化研究进展

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第四纪研究 2024年第3期44卷 837-846页

作者：梁琛李家胜李泉河北地质大学河北石家庄050031 中国科学院地理科学与资源研究所陆地表层格局与模拟院重点实验室北京100101

植物多样性变化及其对气候的响应机制是未来全球变化模拟和生物多样性保护决策的科学基础。对过去长时间尺度植物多样性变化的研究,可为预测未来类似幅度增温场景下生态系统的变化提供依据。国内外众多学者已在基于化石孢粉记录的过去... 详细信息

植物多样性变化及其对气候的响应机制是未来全球变化模拟和生物多样性保护决策的科学基础。对过去长时间尺度植物多样性变化的研究,可为预测未来类似幅度增温场景下生态系统的变化提供依据。国内外众多学者已在基于化石孢粉记录的过去植物多样性重建方面开展了大量工作。文章综述了多种孢粉多样性量化指数、末次冰盛期以来全球各地植物多样性变化趋势以及植物多样性的影响因素等。孢粉多样性重建指数可分为固有指数(丰富度和均匀度)和差异性指数(β指数),分别从多个侧面度量了多样性变化。末次冰盛期以来植物多样性变化可划分出5个阶段,总体呈上升趋势的背景下表现出明显的空间分异。影响过去植物多样性变化的因素主要来自气候等自然因素和人类活动等非自然扰动,表现为长时间尺度变化受到气候变化的主控,晚全新世日益增强的人类活动对植物多样性的影响已经极大地超过了气候变化驱动下的自然变率。人类世以来观测记录显示的生物多样性减少、甚至生物灭绝的主要原因应是人类活动,而非全球变暖。

关键词：古植物多样性孢粉多样性末次冰盛期多样性变化机制

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美国印太复合联盟的构建及影响评析

世界经济与政治论坛 2024年第1期 61-79页

作者：郑海琦李家胜中共中央党校(国家行政学院)国际战略研究院西安交通大学马克思主义学院、亚欧研究中心

联盟是美国“印太战略”的关键支柱。随着美国国内和地区形势的变化,拜登政府着眼于构建印太复合联盟。印太复合联盟综合了联盟和同盟的属性,包含联盟构成圈层化、联盟议程多元化、联盟目标制衡化和联盟基础弹性化四个维度。印太复合联... 详细信息

联盟是美国“印太战略”的关键支柱。随着美国国内和地区形势的变化,拜登政府着眼于构建印太复合联盟。印太复合联盟综合了联盟和同盟的属性,包含联盟构成圈层化、联盟议程多元化、联盟目标制衡化和联盟基础弹性化四个维度。印太复合联盟的产生主要基于分担霸权护持成本、发挥盟友主动性、重塑联盟关系和减少地区国家对“印太战略”的抵触等考量。印太复合联盟以美日韩印澳和欧洲主要盟友为“内核”,东南亚和南亚中小国家为“中间地带”,太平洋岛国为“外围”,综合了安全、经济和地区治理议题,借助议题合作的方式制衡中国,在所谓“民主”价值观下突出意识形态弹性化。美国构建的复合联盟导致印太地区内出现功能相似但成员相异的“平行体系”,加剧地区阵营化态势,还使地区公共产品俱乐部化,甚至与地区国家的需求出现错位,并引发治理冗余和治理失衡并存的现象,削弱了地区国家的获益前景。

关键词：美国印太战略复合联盟地区治理平行体系

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印度中亚政策的进展与局限

印度洋经济体研究 2024年第2期 1-20,152页

作者：李家胜西安交通大学马克思主义学院西安交通大学亚欧研究中心

印度与中亚五国举行领导人线上峰会后,各方构建了多领域对话机制并进一步深化合作。随着阿富汗变局和乌克兰危机爆发,主要大国愈加关注中亚地区,印度为了平衡中国影响力并体现其大国角色也加快推进中亚外交,但是中亚地区风险、大国博弈... 详细信息

印度与中亚五国举行领导人线上峰会后,各方构建了多领域对话机制并进一步深化合作。随着阿富汗变局和乌克兰危机爆发,主要大国愈加关注中亚地区,印度为了平衡中国影响力并体现其大国角色也加快推进中亚外交,但是中亚地区风险、大国博弈态势、印度周边环境及其外交优先事项等因素又进一步限制了印度在中亚影响力的发挥。印度参与中亚事务增强了中亚国家与域外大国合作的灵活性,同时也使中亚地区一体化的进程更具不确定性,并可能弱化地区合作组织的部分功能。中国需要投入更多精力开展中亚外交,与中亚各国携手构建中国-中亚命运共同体。

关键词：印度外交连接中亚政策中印关系一带一路

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汽车焊装车间循环冷却水运行问题分析与研究

工业水处理 2024年第4期44卷 210-214页

作者：陈炳彬卢科镍郑聪张晗历家声上汽大众汽车有限公司宁波分公司浙江宁波315327 宁波浙环科环境技术有限公司浙江宁波315048

汽车焊装车间采用闭式循环水系统对焊接等主要设备进行冷却。研究分析了其循环水系统工艺流程及运行过程中存在的问题,针对问题实施了提升循环水系统水质、增加主管排气阀、使用自主设计优化的气控阀并定期巡检等措施。结果表明,采用的... 详细信息

汽车焊装车间采用闭式循环水系统对焊接等主要设备进行冷却。研究分析了其循环水系统工艺流程及运行过程中存在的问题,针对问题实施了提升循环水系统水质、增加主管排气阀、使用自主设计优化的气控阀并定期巡检等措施。结果表明,采用的措施有效降低了循环水中悬浮物量,季度沉积物由最高720 g减少至32 g;稳定了水流量,降低水气互窜的影响,减少了为排除杂质和空气而排放的循环水,日均补水量由最高15.8 t减少至最低0.5 t,且稳定在2 t以内;降低了由循环水系统故障引起的设备损坏率,保证了自动焊装生产线的设备开动率,累计停线时间由2019年的2 514 min降低到2022年的73 min。

关键词：汽车焊装车间密闭式循环水系统气控阀水气互窜

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Abdominal Grey Color Variation along an Elevation Gradient in a lizard

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Asian Herpetological Research 2023年第2期14卷 156-166页

作者： Zian WEI jiasheng li Tao WANG Minglu YANG Yuanting JIN College of life Sciences China Jiliang UniversityHangzhou 310018ZhejiangChina College of life Sciences and Medicine Zhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina College of life Sciences Northwest Normal UniversityLanzhou 730070GansuChina

Color variation among populations is thought to be either due to genetic variation or phenotype *** this study,we found that an agamid lizard,Phrynocephalus theobaldi,inhabiting elevations greater than any other reptile,displayed a significantly darker spotted marking on the central ventral abdomen in higher populations than in lower *** grey spotted area only occurred in elevations>4200 m,and also increased with increased *** ratio of the size of the dark colored area to the degree of skin luminance/reflectance was used to test whether the lizard has a larger and darker spotted area at higher *** ratio was significantly positively associated with elevation rather than substrate *** lizard did not display sexual difference in this *** had a significant influence on the brightness of central abdomen,but temperature-related plasticity of this trait was much smaller than the magnitude of the difference between higher(>4200 m)and lower populations(<4200 m).Common garden experiments showed that genetic inheritance,rather than phenotype plasticity,played a dominant role in this *** research addressed the darkness of a body region that is rarely analyzed because it is shielded from direct *** idea that ventral color could be related to thermoregulation is shown to be worthy of further research.

关键词： central abdomen color variation common garden experiments elevation reptile temperature

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基于卷积神经网络算法的苹果疤痕识别技术

湖南城市学院学报（自然科学版） 2024年第4期33卷 55-59页

作者：宋如梦李加升张富城安徽新华学院大数据与人工智能学院合肥230000 湖南城市学院信息与电子工程学院湖南益阳413000

针对在苹果外部品质检测中,传统方法存在识别精度低、速度慢等问题,本文提出了一种基于卷积神经网络算法的图像处理技术。首先,采取7种数据增强方法对原数据进行增强处理,用以扩展数据集,降低模型训练过拟合的风险;其次,对Faster R-CNN... 详细信息

针对在苹果外部品质检测中,传统方法存在识别精度低、速度慢等问题,本文提出了一种基于卷积神经网络算法的图像处理技术。首先,采取7种数据增强方法对原数据进行增强处理,用以扩展数据集,降低模型训练过拟合的风险;其次,对Faster R-CNN中的特征提取网络进行优化,采用K-means聚类算法优化RPN网络,使数据集重新聚类生成新的anchor长宽比设置,并增加模型对苹果疤痕信息的提取;最后,以原始Faster R-CNN模型作为对照模型,以识别精度和速度为评价指标进行试验。结果表明:基于EfficientNet B7特征提取的K-means-Eff-CNN模型准确度达到了94.7%,且能够在0.1 s内识别出苹果疤痕。

关键词：卷积神经网络苹果疤痕图像 Eff-CNN RPN

Complete Mitochondrial Genome Analysis of Daphniopsis tibetana(Branchiopoda:Diplostraca):New Insights into the Taxonomy of the Genus and Its Phylogenetic Implications for Branchiopoda

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Journal of Ocean University of China 2022年第6期21卷 1622-1632页

作者： liU Bingjian PENG Ying liU Yifan li jiasheng ZHANG Kun CHEN Jian GONG li liU liqin LÜZhenming ZHANG Chi National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization Zhejiang Ocean UniversityZhoushan 316022China Institute of Fisheries Science Tibet Academy of Agricultural and Animal Husbandry SciencesLhasa 850002China Key Laboratory of Tropical Marine Bio-Resources and Ecology Chinese Academy of SciencesGuangzhou 510301China

Daphniopsis tibetana is widely distributed in Xinjiang,Qinghai,Tibet of China,as well as in Russia and India,which is the dominant zooplankton in many high-altitude(4000 m)salt *** can adapt to saline waters,whereas the other species of the superorder Cladocera can only inhabit in ***,the phylogenetic status of *** in Branchiopoda remains unclear primarily because of limited *** this study,complete mitochondrial genome sequences of *** were sequenced and annotated for the first time to obtain a comprehensive understanding of its phylogenetic *** complete mitogenome of *** is 16196 bp in *** contains 37 genes,including two ribosomal RNAs(12S and 16S rRNAs)genes,22 transfer RNA(tRNA)genes,13 protein-coding genes,and one non-coding *** overall base composition is 29.6%A,33.2%T,19.0%G,and 18.2%C with a high AT bias(62.8%).Except for trnS1(GCT),most tRNAs have a typical cloverleaf secondary *** analysis based on maximum likelihood and Bayesian inference generates identical phylogenetic topology and shows the phylogenetic status of ***,which reconfirm the distinction between the genera Daphniopsis and ***,the class Branchiopoda is clustered into three clades(Anostraca,Notostraca,and Diplostraca)with high support *** results provide not only a comprehensive understanding of the characteristics of *** mitogenome and its phylogenetic position in Diplostraca,but also information for future research on the phylogeny of Branchiopoda.

关键词： Daphniopsis tibetana mitogenome phylogenetic analysis Branchiopoda Diplostraca