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基于银川电离层垂测仪电子浓度反演的一次强电离层暴观测

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空间科学学报 2024年第5期44卷 782-793页

作者：韩思佳梁珍珍郭伟王彩云方青钰李玲玲中国科学院国家空间科学中心微波遥感技术重点实验室北京100190 中国科学院大学北京100049 中国科学院空天信息创新研究院北京100094

根据银川电离层垂测仪的回波数据,采用脉冲压缩技术,使用Bernoulli映射序列对发射信号进行编码,解决实际探测中回波信号混合强杂波干扰的问题,从而获得高质量频高图.为从图中提取电离层的关键信息,将信号处理问题转换成计算机视觉中的... 详细信息

根据银川电离层垂测仪的回波数据,采用脉冲压缩技术,使用Bernoulli映射序列对发射信号进行编码,解决实际探测中回波信号混合强杂波干扰的问题,从而获得高质量频高图.为从图中提取电离层的关键信息,将信号处理问题转换成计算机视觉中的语义分割任务,构建原始频高图数据集,并进行离散化和人工标注等预处理.通过训练c GAN神经网络分析得到频高图中各层回波的特征参数,达到分割不同描迹的目的.采用改进式国际参考电离层底部反演模型和NeQuick顶部模型对垂测仪上空的电子浓度剖面进行反演,根据张衡一号卫星的实测数据对顶部的计算结果进行修正.通过将计算得到的总电子浓度与CDDIS公开的数据结果对比,验证了垂测仪数据的准确性.在此基础上,结合高沙窝磁通门的地磁数据,垂测仪于2023年4月23-24日的大地磁暴期间成功观测到电离层异常变化的全过程并给出了总电子浓度变化结果,为探究中国西部电磁环境变化提供准确可靠的观测数据.

关键词：电离层垂测仪 Bernoulli映射序列 cGAN网络频高图电子浓度反演磁暴观测

孕妇分娩自我效能在孕期生殖健康素养与分娩意向之间的中介效应

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复旦学报（医学版） 2024年第5期51卷 765-771页

作者：徐方萍朱新丽王晓娇朱春香顾春怡复旦大学附属妇产科医院护理部上海200011 复旦大学护理学院上海200032 复旦大学附属妇产科医院产科上海200090 复旦大学附属妇产科医院LDR病房上海200011

目的探讨孕妇分娩自我效能在孕期生殖健康素养与分娩意向间的中介效应,为产科医护人员开展科学合理的分娩决策支持干预提供参考依据。方法使用一般资料调查表、孕期生殖健康素养问卷、分娩自我效能量表,以复旦大学附属妇产科医院产科门... 详细信息

目的探讨孕妇分娩自我效能在孕期生殖健康素养与分娩意向间的中介效应,为产科医护人员开展科学合理的分娩决策支持干预提供参考依据。方法使用一般资料调查表、孕期生殖健康素养问卷、分娩自我效能量表,以复旦大学附属妇产科医院产科门诊为现场调查点,采用便利抽样法对2020年10月至2021年2月到院产检的孕晚期女性进行问卷调查。通过线性回归和Logistic回归分析法分别评估孕期生殖健康素养及分娩自我效能与分娩意向之间的关联,采用MacKinnon乘积分布法评估分娩自我效能在孕期生殖健康素养与分娩意向之间中介效应的相关性。结果共纳入343例孕妇,分娩意向回归分析显示:孕期生殖健康素养(c’=1.644,95%CI:2.223~12.059)、分娩自我效能(β=2.211,95%CI:6.300~13.215)与阴道分娩意向显著关联(P<0.001);分娩自我效能与孕期生殖健康素养呈显著正相关(β=1.280,95%CI:0.102~0.165,P<0.01);分娩自我效能是孕期生殖健康素养与分娩意向的中介变量,占总效应值的24.8%。结论分娩自我效能在孕期生殖健康素养与分娩意向的关联中具有中介作用,产科医护人员应注重孕产期保健和分娩教育,提高孕妇分娩自我效能和孕期生殖健康素养水平,支持其做出科学的分娩意向决策,促进正常分娩。

关键词：妊娠健康素养自我效能分娩意向中介效应

跳马训练所致膝前交叉韧带损伤与临床转归分析

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中国矫形外科杂志 2024年第12期32卷 1075-1082页

作者：徐健李中耀吴毅东甘露于康康许金芳曹丽董晨辉李春宝解放军联勤保障部队第九四〇医院运动医学科甘肃兰州730050 解放军联勤保障部队第九四〇医院神经外科甘肃兰州730050 解放军总医院第四医学中心骨科医学部北京100853 解放军海军军医大学军队卫生统计学教研室上海200435

[目的]探讨跳马训练致膝前交叉韧带损伤(anterior cruciate ligament injury, ACli)的风险因素和术后复训效果。[方法]回顾性分析2019年10月1日—2022年10月31日联勤保障部队第九四〇医院收治的因跳马训练致ACli的伤员,比较其一般信息... 详细信息

[目的]探讨跳马训练致膝前交叉韧带损伤(anterior cruciate ligament injury, ACli)的风险因素和术后复训效果。[方法]回顾性分析2019年10月1日—2022年10月31日联勤保障部队第九四〇医院收治的因跳马训练致ACli的伤员,比较其一般信息、损伤情况、随访及复训等资料。[结果]纳入356例因跳马训练致膝关节损伤伤员,其中跳马一训练致伤117例,跳马二训练致伤158例,跳马三训练致伤81例。与术前相比,术后不同年龄[0.05)。随访期间356例伤员中达到复训标准99例(27.8%),平均需16个月恢复至复训状态。[结论]跳马训练是ACli的重要致病因素,ACLR术后患者的膝关节功能恢复良好,但伤后恢复周期长、复训率低。

关键词：军事训练跳马训练前交叉韧带损伤复训预防

Load Balance Strategy of Data Routing Algorithm Using Semantics for Deduplication Clusters

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Journal of Electronic Science and Technology 2017年第3期15卷 277-282页

作者： Ze-Jun Jiang Zhi-Ke Zhang li-fang Wang Chin-Chen Chang li liu School of Computer Science Northwestern Polytechnical University Xi'an 710072 IBM China Systems &Technology Lab Beijing 100193 Department of Information Engineering and Computer Science Feng Chia University Taichung 40724

The backup requirement of data centres is tremendous as the size of data created by human is massive and is increasing *** node deduplication cannot meet the increasing backup requirement of data centres.A feasible way is the deduplication cluster,which can meet it by adding storage *** data routing strategy is the key of the deduplication ***（data routing strategy using semantics） improves the storage utilization of MCS（minimum chunk signature） data routing strategy a ***,for the large deduplication cluster,the load balance of DRSS is worse than *** improve the load balance of DRSS,we propose a load balance strategy used for DRSS,namely *** a node is overloaded,DRSSLB iteratively migrates the current smallest container of the node to the smallest node in the deduplication cluster until this overloaded node becomes non-overloaded.A container is the minimum unit of data *** files sharing the same features or file names are stored in the same *** ensures the similar data groups are still in the same node after rebalancing the *** use the dataset from the real world to evaluate *** results show that,for various numbers of nodes of the deduplication cluster,the data skews of DRSSLB are under predefined value while the storage utilizations of DRSSLB do not nearly increase compared with DRSS,with the low penalty（the data migration rate is only6.5% when the number of nodes is 64）.

关键词： Index Terms--Data routing strategy deduplicationcluster semantics load balance.

Extractable Fractions of Metals in Sewage Sludges from Five Typical Urban Wastewater Treatment Plants of China

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Pedosphere 2006年第6期16卷 756-761页

作者： WANG Chao li Xiao-Chen WANG Pei-fang ZOU li-Min MA Hai-Tao Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of Education Nanjing 210098 China School of Environmental Science and Engineering Hohai University Nanjing 210098 China

Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.

关键词： fractions heavy metals sequential extraction sewage sludge

The Role of Bottom Currents on the Morphological Development Around a Drowned Carbonate Platform,NW South China Sea

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Journal of Ocean University of China 2022年第4期21卷 801-812页

作者： YU Kaiqi ALVES Tiago M li Wei li Shuang li Jian ZHAO fang WU Shiguo ZHAN Wenhuan CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academyof SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China 3D Seismic Laboratory School of Earth and Ocean SciencesCardiff UniversityCardiff CF103ATUK Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

The seafloor around carbonate platforms is largely shaped and modified by downslope ***,the role of alongslope processes,including bottom currents,on the morphological development of carbonate platforms remains poorly ***,we use high-resolution multibeam bathymetric data and two-dimensional seismic profiles to investigate the detailed sea-floor morphology around the Zhongjianbei carbonate platform(ZCP)in the northwest South China Sea.A series of depositional bodies and erosional channels are identified to the south of the ZCP and are interpreted as contourite drifts and channels resulted from the interaction between bottom currents and bathymetric *** addition,active fluid seepages have led to the formation of widespread pockmarks on the ***,the contourite channels and widespread pockmarks also show a close relationship in their *** propose that the contourite channels around the ZCP are evolved from the coalescence of pockmarks under the persistent erosion of bottom *** on the morphological analysis,we reconstruct the past bottom-current pathways around the ZCP that are parallel to the platform slopes and heading to the *** study provides new insights into the formation of complex bathymetry and helps understanding how bottom currents and active fluid seepages can influence the morphological development around carbonate platforms.

关键词： carbonate platform seafloor morphology contourite channels bottom currents fluid seepages South China Sea

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汽油分类方法研究进展

化学研究与应用 2024年第4期36卷 689-695页

作者：张冠男刘占芳孙振文周正李光耀李亚军朱军公安部鉴定中心北京100038

汽油是放火犯罪中最常使用的助燃剂,其提取和检验有重要意义。通过牌号、品牌、产地等信息对汽油进行分类,有助于推断汽油来源和串并比对,缩小侦察范围。当前的汽油分类方法大多可以区分不同汽油的辛烷值、添加剂和地域信息,对放火案件... 详细信息

汽油是放火犯罪中最常使用的助燃剂,其提取和检验有重要意义。通过牌号、品牌、产地等信息对汽油进行分类,有助于推断汽油来源和串并比对,缩小侦察范围。当前的汽油分类方法大多可以区分不同汽油的辛烷值、添加剂和地域信息,对放火案件侦办具有借鉴作用。本文对汽油分类基础理论进行了介绍,概述了国内外近年来基于红外光谱、拉曼光谱、气相色谱、质谱等技术的汽油分类方法研究,旨在为汽油分类技术在法庭科学中的应用提供参考。文末讨论了现有汽油分类方法在实际检材中面临的问题,展望了相关研究方向和未来发展趋势。

关键词：汽油化学计量学法庭科学色谱光谱

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激光冲击强化技术在核电领域的研究进展

中国表面工程 2024年第1期37卷 41-58页

作者：蔡振兵周龙龙俞延庆方修洋余施佳周留成何卫锋李国杰何艳磊西南交通大学摩擦学研究所成都610031 空军工程大学等离子体动力学重点实验室西安710038 西安天瑞达光电技术股份有限公司西安710077

激光冲击强化技术属于改善金属性能的重要表面形变强化技术,因其独特的技术优势在航天及船舶领域获得广泛应用。随着科技的发展研发出多种激光冲击强化技术,并逐渐开始在核电装备领域获得应用,然而针对该技术在核电领域的研究进展缺乏... 详细信息

激光冲击强化技术属于改善金属性能的重要表面形变强化技术,因其独特的技术优势在航天及船舶领域获得广泛应用。随着科技的发展研发出多种激光冲击强化技术,并逐渐开始在核电装备领域获得应用,然而针对该技术在核电领域的研究进展缺乏系统的综述。先通过介绍不同表面形变强化技术,叙述激光冲击强化技术的发展,阐述激光冲击强化机制,最后综述激光冲击强化技术在核电领域的应用研究进展。总结发现,激光冲击强化技术可有效改善核电领域材料力学、摩擦磨损及腐蚀性能,但传统和添加辅助手段激光冲击强化技术受约束层和吸收层影响较大,无涂激光冲击强化技术对金属易产生热效应,飞秒激光冲击强化影响层浅且强化效果差,不同工艺技术在核电领域提升摩擦磨损性能研究较少。对不同工艺激光冲击强化机理及在核电领域材料不同性能的提升进行深入研究,为进一步提升激光冲击强化技术在核电领域材料的应用提供理论基础,可为核电领域关键装备进行强化、提升核电装备运行寿命提供参考。

关键词：激光强化核电装备摩擦磨损腐蚀极端环境先进制造

Maastrichtian Charophyte Flora from the Jiankou Section of the Jiaolai Basin

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 556-557页

作者： li Sha fang Yanan WANG He WANG Qifei ZHANG Haichun State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences.Nanjing 210008China Nanjing Institute of Geology and Palaeontology and Center for Excellence in life and Palaeoenvironment Chinese Academy of SciencesNanjing 210008China

The latest Cretaceous strata of the Jiaolai Basin were studied in two scientific cores,including LK-1 drilled by the Institute of Geology,Chinese Academy of Geological Sciences(li et al.,2018;li et al.,2020),and JK-1 drilled by the Shandong Institute of the Geological Survey and Institute of Geology,Chinese Academy of Geological Sciences(Xu et al.,2017).However,outcrop sections were poorly studied,and the latest Cretaceous charophyte flora in particular had not previously been adequately documented from outcrops in the Jiaolai area.

关键词： Cretaceous Basin strata