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航天器轨道机动自适应逆向移动滑窗检测方法

国防科技大学学报 2024年第4期46卷 45-53页

作者：李泽越杨震李海阳罗亚中国防科技大学空天科学学院湖南长沙410073 空天任务智能规划与仿真湖南省重点实验室湖南长沙410073

以两行轨道根数为数据来源,提出采用逆向移动滑窗的自适应轨道机动检测方法。建立检测窗口的自适应配置模型以获得不同目标的检测窗口,采用交叉弧段预报思想更精确地估计机动时刻,通过逆向移动滑窗方法实现近实时机动检测。将检测结果... 详细信息

以两行轨道根数为数据来源,提出采用逆向移动滑窗的自适应轨道机动检测方法。建立检测窗口的自适应配置模型以获得不同目标的检测窗口,采用交叉弧段预报思想更精确地估计机动时刻,通过逆向移动滑窗方法实现近实时机动检测。将检测结果与真实机动以及已有文献中的检测结果进行比较,结果表明:新方法能够适应不同轨道空间目标机动检测的窗口配置,且在给定仿真条件下检测成功率可以达到90%以上,机动时刻估计准确度与已有方法对比有显著的提升;仿真结果表明新方法可以应用于近实时的轨道机动检测。

关键词：轨道机动移动滑窗轨道异常检测空间态势感知

FT5a interferes with the Dt1-AP1 feedback loop to control flowering time and shoot determinacy in soybean

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Journal of Integrative Plant Biology 2021年第6期63卷 1004-1020页

作者： lin Yue Xiaoming li Chao Fang liyu Chen Hui Yang Jie Yang Zhonghui Chen haiyang Nan linnan Chen Yuhang Zhang haiyang li Xingliang Hou Zhicheng Dong James LWeller Jun Abe Baohui liu Fanjiang Kong School of life Sciences Innovative Center of Molecular Genetics and EvolutionGuangzhou UniversityGuangzhou 510006China Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement&Guangdong Provincial Key Laboratory of Applied Botany South China Botanical Gardenthe Chinese Academy of SciencesGuangzhou 510650China University of the Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Crop Genetics and Germplasm Enhancement National Center for Soybean ImprovementNanjing Agricultural UniversityNanjing 210095China School of Natural Sciences University of TasmaniaHobartTasmania 7001Australia Research Faculty of Agriculture Hokkaido UniversitySapporo 060‐8589Japan The Innovative Academy of Seed Design Key Laboratory of Soybean Molecular Design BreedingNortheast Institute of Geography and Agroecologythe Chinese Academy of SciencesHarbin 1500000Chin

Flowering time and stem growth habit determine inflorescence architecture in soybean, which in turn influences seed yield. Dt1, a homolog of Arabidopsis TERMINAL FLOWER 1(TFL1), is a major controller of stem growth habit, but its underlying molecular mechanisms remain unclear.Here, we demonstrate that Dt1 affects node number and plant height, as well as flowering time,in soybean under long-day conditions. The b ZIP transcription factor FDc1 physically interacts with Dt1, and the FDc1-Dt1 complex directly represses the expression of APETALA1(AP1). We propose that FT5 a inhibits Dt1 activity via a competitive interaction with FDc1 and directly upregulates AP1. Moreover, AP1 represses Dt1 expression by directly binding to the Dt1 promoter, suggesting that AP1 and Dt1 form a suppressive regulatory feedback loop to determine the fate of the shoot apical meristem. These findings provide novel insights into the roles of Dt1 and FT5 a in controlling the stem growth habit and flowering time in soybean, which determine the adaptability and grain yield of this important crop.

关键词： AP1 Dt1 FDc1 flowering FT5a soybean stem growth habit

鼻腔微生物群对慢性鼻窦炎伴鼻息肉患者鼻内镜手术后鼻功能的影响

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中国耳鼻咽喉头颈外科 2024年第1期31卷 41-44页

作者：吴玉彬李倩李海洋北京市大兴区人民医院耳鼻咽喉科北京102600

目的探讨分析鼻腔微生物群对慢性鼻窦炎伴鼻息肉患者鼻内镜手术后鼻功能的影响。方法选取北京市大兴区人民医院2021年5月~2022年5月择期进行鼻内镜手术治疗的88例慢性鼻窦炎伴鼻息肉患者,采用高通量测序技术分析鼻腔内分泌物中微生物群... 详细信息

目的探讨分析鼻腔微生物群对慢性鼻窦炎伴鼻息肉患者鼻内镜手术后鼻功能的影响。方法选取北京市大兴区人民医院2021年5月~2022年5月择期进行鼻内镜手术治疗的88例慢性鼻窦炎伴鼻息肉患者,采用高通量测序技术分析鼻腔内分泌物中微生物群分布情况,将患者分为微生物阴性组24例、细菌阳性组42例和真菌阳性组22例。比较两组视觉模拟量表(VAS)评分、Lund-Kennedy内镜评分及Lund-Mackay CT评分评估患者鼻功能并采用鼻内镜评估鼻黏膜损伤程度,并检测鼻黏膜组织基底膜厚度。结果88例慢性鼻窦炎伴鼻息肉患者鼻腔分泌物中共检出病原菌64例,细菌占比47.73%,真菌占比25.00%。术后三组患者鼻功能评分较术前明显降低,组间两两比较差异具有统计学意义(P0.05)。结论鼻腔分泌物中细菌和真菌能影响慢性鼻窦炎伴鼻息肉患者鼻内镜手术后鼻功能恢复,影响鼻内镜手术效果。

关键词：微生物学鼻腔鼻窦炎鼻息肉内窥镜检查鼻功能

ITRF2014框架下顾及降雨量与水文负载的CMONOC坐标时间序列关系分析

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武汉大学学报（信息科学版） 2024年第6期49卷 960-969页

作者：何月帆聂桂根武曙光李海洋廖密郭雨武汉大学卫星导航定位技术研究中心湖北武汉430079 地球空间信息技术协同创新中心湖北武汉430079 湖北珞珈实验室湖北武汉430072

水文负载对中国大陆构造环境监测网络(crustal movement observation network of China,CMONOC)测站坐标时间序列具有重要的影响,而降雨量直接影响了水文负载的量级大小。利用ITRF2014(international terrestrial reference frame 2014)参考框架下CMONOC坐标时间序列、MERRA2(modern-era retrospective analysis for research and applications, version 2)水文负载模型以及中国区域降雨量数据来分析三者之间的关系。结果表明,水文负载对CMONOC测站的影响主要体现在垂直方向上,尤其在珠江流域、长江流域以南、西南以及东南诸河流域,水文负载对测站位移的影响尤为显著,水文负载序列的均方根最大可达5.47 mm。水文负载和降雨量都呈现出较为明显的纬度相关性,纬度越高,其量级越小,二者与纬度的线性拟合优度分别为0.63和0.55;同时,降雨量与水文负载也呈现明显的线性关系,拟合优度为0.49,且随着年均降雨量的增加,水文负载的量级会随之增大。对于周期性信号,降雨量、水文负载以及CMONOC坐标时间序列具有一致性,水文负载的周年振幅和CMONOC坐标时间序列的周年振幅与年均降雨量的拟合优度分别为0.64和0.37。在研究水文负载对GNSS坐标时间序列的影响时,除了土壤湿度、积雪以及冠层水,降雨量也是不可忽略的因素。

关键词：水文负载降雨量 CMONOC坐标时间序列拟合优度周年振幅

钢-铝及铝-铝接头自冲铆接和流钻螺钉连接对比研究

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锻压技术 2024年第4期49卷 138-145,160页

作者：丁志勇李海洋顾成波江铃汽车股份有限公司产品研发总院江西南昌330000 广西艾盛创制科技有限公司广西柳州545001

对汽车用高强度钢、挤压铝和两种压铸铝共4种材料,分别采用自冲铆接和流钻螺钉建立了钢-铝和铝-铝接头,并通过试验,对比研究了厚度、材料、搭接顺序对两类接头的成形质量和力学性能的影响。结果表明:钢-铝接头中,自冲铆接接头的峰值力... 详细信息

对汽车用高强度钢、挤压铝和两种压铸铝共4种材料,分别采用自冲铆接和流钻螺钉建立了钢-铝和铝-铝接头,并通过试验,对比研究了厚度、材料、搭接顺序对两类接头的成形质量和力学性能的影响。结果表明:钢-铝接头中,自冲铆接接头的峰值力整体上优于流钻螺钉接头,但能量吸收低于后者;流钻螺钉接头受到螺钉断裂的影响较小,而自冲铆接接头在铆钉断裂后,能量吸收显著降低;铝-铝接头中,流钻螺钉接头的峰值力和能量吸收均优于自冲铆接接头,厚板置于下层可提高流钻螺钉接头的峰值力和能量吸收;同类接头中,铝-铝接头的整体表现优于钢-铝接头。

关键词：钢-铝接头铝-铝接头自冲铆接流钻螺钉峰值力能量吸收

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辽宁灯塔兴顺铁矿地质特征及找矿方向

现代矿业 2024年第1期40卷 53-56页

作者：李海洋辽宁省地质矿产研究院有限责任公司

为摸清兴顺铁矿深部资源潜力,扩大矿山资源储量规模,在地质测量、磁法测量、钻探及巷道编录的基础上,对矿床地质特征和矿体赋存规律等进行综合研究,分析矿床成因、总结找矿标志。结果表明,矿体赋存层位为太古宙鞍山岩群茨沟岩组,矿石自... 详细信息

为摸清兴顺铁矿深部资源潜力,扩大矿山资源储量规模,在地质测量、磁法测量、钻探及巷道编录的基础上,对矿床地质特征和矿体赋存规律等进行综合研究,分析矿床成因、总结找矿标志。结果表明,矿体赋存层位为太古宙鞍山岩群茨沟岩组,矿石自然类型为磁铁石英岩,是典型的鞍山式沉积变质型铁矿。矿体向深部延伸趋势明显,具有良好的找矿潜力。

关键词：铁矿床地质特征找矿方向

Does access to credit reduce SMEs’tax avoidance?Evidence from a regression discontinuity design

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Financial Innovation 2021年第1期7卷 380-402页

作者： Xiaowei Kong Deng‑Kui Si haiyang li Dongmin Kong School of Economics and Management Dongguan University of TechnologyDongguanChina Department of Finance Qingdao UniversityQingdaoChina School of Finance Zhongnan University of Economics and LawWuhanChina School of Economics Huazhong University of Science and TechnologyWuhanChina

This study investigates the effect of targeted reserve requirement ratio cuts(TRRRCs)on tax avoidance among small and micro enterprises(SMEs)with operating revenues below specific cutoffs in China.Using a regression discontinuity design,we causally show that,by increasing loan availability,TRRRCs significantly alleviate the financial constraints and cash dependence of SMEs and consequently reduce tax avoidance.This is especially the case among firms with lower market power and higher entertainment and travel costs.Our findings provide evidence for the real effect of TRRRCs on corporate tax avoidance and show the inclusive effect of TRRRCs on SMEs.In doing so,we indirectly reveal a rent-seeking channel underlying bank lending,thus offering clear policy implications for regulators.

关键词： Access to finance Small and micro enterprises(SMEs) Tax avoidance Targeted reserve requirement ratio cuts(TRRRCs)

Radiofrequency field enhanced chemical ionization with vacuum ultraviolet lamp for miniature time-of-flight mass spectrometer

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Chinese Chemical Letters 2018年第5期29卷 707-710页

作者： lijuan Zhou Jichun Jiang Kun Zhao Jinxu li Chenxin Wu haiyang li Di Tian Keyong Hou College of Instrumentation & Electrical Engineering Jilin University Changchun 130023 China Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China University of Chinese Academy of Sciences Beijing 100039 China

It is difficult to rapidly and on-line detect trace volatile organic compounds for miniature massspectrometry due to its limited sampling volume at slow pumping speed. In this paper, we developed anew radiofrequency field enhanced chemical ionization source （RF-ECI） with vacuum ultraviolet （VUV）lamp by coupling radiofrequency electric field and direct-current field together. The experiment resultsshowed that the sensitivity of benzene, toluene, hydrogen sulfide and other compounds increased by 2-3orders of magnitude under the introduction of RF-ECI comparing to traditional single photon ionization（SPI）. At the same time, the reagent ion of O2＋ realized the charge transfer reaction chemical ionization,and the RF-ECI effectively expanded the detection range of the VUV lamp based SPI. The VUV lamp hasinherent advantages in the on-site analytical instrument for its small size and low power consumption,and the VUV lamp based RF-ECI miniature time-of-flight mass spectrometer （TOFMS） has a limit-of-detection for H2S as low as 0.0571 mg/m3, and it is expected to be used widely in the field of on-site rapidanalvsis.

关键词： Radio-frequency field enhanced chemical ionization Vacuum ultraviolet lamp Single photon ionization Miniature time-of-flight mass spectrometer On site analysis

A recent retrotransposon insertion of J caused E6 locus facilitating soybean adaptation into low latitude

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Journal of Integrative Plant Biology 2021年第6期63卷 995-1003页

作者： Chao Fang Jun liu Ting Zhang Tong Su Shichen li Qun Cheng lingping Kong Xiaoming li Tiantian Bu haiyang li lidong Dong Sijia Lu Fanjiang Kong Baohui liu Innovative Center of Molecular Genetics and Evolution School of Life SciencesGuangzhou UniversityGuangzhou 510006China The Innovative Academy of Seed Design Key Laboratory of Soybean Molecular Design BreedingNortheast Institute of Geography and Agroecologythe Chinese Academy of SciencesHarbin 150000China Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement South China Botanical Gardenthe Chinese Academy of SciencesGuangzhou 510650China National Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Collaborative Innovation Center for Modern Crop ProductionNanjing Agricultural UniversityNanjing 210095China

Soybean(Glycine max) is an important legume crop that was domesticated in temperate regions.Soybean varieties from these regions generally mature early and exhibit extremely low yield when grown under inductive short-day(SD) conditions at low latitudes. The long-juvenile(LJ) trait, which is characterized by delayed flowering and maturity,and improved yield under SD conditions, allowed the cultivation of soybean to expand to lower latitudes. Two major loci control the LJ trait: J and E6. In the current study, positional cloning, sequence analysis, and transgenic complementation confirmed that E6 is a novel allele of J, the ortholog of Arabidopsis thaliana EARLY FLOWERING 3(ELF3). The mutant allele e6^(PG), which carries a Ty1/Copia-like retrotransposon insertion, does not suppress the legume-specific flowering repressor E1, allowing E1 to inhibit Flowering Locus T(FT) expression and thus delaying flowering and increasing yields under SD conditions. The e6^(PG)allele is a rare allele that has not been incorporated into modern breeding programs.The dysfunction of J might have greatly facilitated the adaptation of soybean to low latitudes. Our findings increase our understanding of the molecular mechanisms underlying the LJ trait and provide valuable resources for soybean breeding.

关键词： E6 long-juvenile(LJ)trait J Ty1/copia-like retrotransposon