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Orbit and clock products for quad-system satellites with undifferenced ambiguity fixing approach

Satellite Navigation 2024年第1期5卷 125-139页

作者： Jiaqi Wu Xingxing Li Yongqiang Yuan Keke Zhang Xin Li Jiaqing Lou yun xiong School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China Hubei Luojia Laboratory 129 Luoyu RoadWuhan430079China German Research Centre for Geosciences GFZ Telegrafenberg14473PotsdamGermany Technische Universitat Berlin(TUB) Straße Des 17.Juni10623BerlinGermany

Integer Ambiguity Resolution(IAR)can significantly improve the accuracy of GNSS Precise Orbit Determination(POD).Traditionally,the IAR in POD is achieved at the Double Differenced(DD)level.In this contribution,we develop an Un-Differenced(UD)IAR method for Global Positioning System(GPS)+BeiDou Navigation Satellite System(BDS)+Galileo navigation satellite system(Galileo)+Global'naya Navigatsionnaya Sputnikovaya Sistema(GLONASS)quad-system POD by calibrating UD ambiguities in the raw carrier phase and generating the so-called carrier range.Based on this method,we generate the UD ambiguity-fixed orbit and clock products for the Wuhan Innovation Application Center(IAC)of the International GNSS Monitoring and Assessment System(iGMAS).One-year observations in 2020 from 150 stations are employed to investigate performance of orbit and clock products.Notably,the UD Ambiguity Resolution(AR)yields more resolved integer ambiguities than the traditional DD AR,scaling up to 9%,attributable to its avoidance of station baseline formation.Benefiting from the removal of ambiguity parameters,the computational efficiency of parameter estimation undergoes a substantial 70%improvement.Compared with the float solution,the orbit consistencies of UD AR solution achieve the accuracy of 1.9,5.2,2.8,2.1,and 2.7 cm for GPS,BeiDou-2 Navigation Satellite System(BDS-2),BeiDou-3 Navigation Satellite System(BDS-3),Galileo,and GLONASS satellites respectively,reflecting enhancements of 40%,24%,54%,34%,and 42%.Moreover,the standard deviations of Satellite Laser Ranging(SLR)residuals are spanning 2.5–3.5 cm,underscoring a comparable accuracy to the DD AR solution,with discrepancies below 5%.A notable advantage of UD AR lies in its capability to produce the Integer Recovered Clock(IRC),facilitating Precise Point Positioning(PPP)AR without requiring additional Uncalibrated Phase Delay(UPD)products.To assess the performance of quad-system kinematic PPP based on IRC,a network comprising 120 stations is utilized.In comparison to the float solution,the IR

关键词： Multi-GNSS Precise orbit determination Integer recover clock Undifferenced ambiguity resolution iGMAS innovation application center

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Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 221-233页

作者：刘生鹏 XU Zhi ZHANG Xinyuan WEI Huan xiong yun DING Yigang HUANG Wenbo 许莉莉 Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Key Laboratory for Green Chemical Process of Ministry of EducationSchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443007China School of Technology Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China

Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites.

关键词： polyphosphazene thermoplastic polyurethane flame retardancy aluminum hypophosphite surface polymerization

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Mammals of Gaoligong Mountain in China:Diversity,distribution,and conservation

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Zoological Research(Diversity and Conservation) 2024年第1期1卷 3-19页

作者： Quan Li Xue-You Li Wen-Qiang Hu Wen-Yu Song Shui-Wang He Hong-Jiao Wang Zhe-Chang Hu Meng-Cheng Li Kenneth Otieno Onditi Zhong-Zheng Chen Chang-Zhe Pu yun xiong Cai-Hong Rao Fu-You Zhang Chang-Sheng Zuo Xue-Long Jiang State Key Laboratory of Genetic Resources and Evolution&yunnan Key Laboratory of Biodiversity and Ecological Conservation of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Gaoligong Mountain Forest Ecosystem Observation and Research Station of yunnan Province&Dulongjiang Forest Ecosystem Research Station KunmingYunnan 650223China University of Chinese Academy of Sciences Beijing 101408China Vector Laboratory Institute of Pathogens and VectorsYunnan Provincial Key Laboratory for Zoonosis Control and PreventionDali UniversityDaliYunnan 671000China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui 241002China Gongshan Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673500China Fugong Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673400China Baoshan Administrative Bureau of Gaoligongshan National Nature Reserve BaoshanYunnan 678000China Administrative Bureau of Tongbiguan Provincial Nature Reserve DehongYunnan 679300China

Gaoligong Mountain(hereafter,GLGM)is located at the intersection of Myanmar and China’s yunnan Province and Xizang Zizhiqu,and spans three globally significant biodiversity hotspots:the Himalayas,Indo-Burma,and the Mountains of Southwest China.Although surveys of mammals in this ecologically important region have a long history,there is no comprehensive systematic checklist and distribution account of the mammals of GLGM.Here,we compiled a mammal species checklist of GLGM based on thorough field investigations and literature reviews.We also examined specimen collections and applied camera trapping surveys to explore the region’s mammal diversity and distribution patterns.We recorded 212 mammal species in nine orders,33 families,and 119 genera,which accounts for 30.5%of China’s mammal species,and a high proportion of nationally protected(50)and globally threatened(29)species.Mammal species richness showed a symmetrical unimodal curve along the elevation gradient,peaking at intermediate elevations(2000 to 2500 m above sea level(asl)),and increasing generally from south to north,slightly higher in the east slope than in the west.Cluster analysis and non-metric multidimensional scaling revealed three distinct elevational assemblages(3500 m asl)and significant south-to-north variation,but no substantial differences between the east and west slopes.The GLGM present a unique conservation value due to the high proportions of rare and endangered mammal species,complex faunal composition,high endemism,and being the distribution boundary for many species.This study is an important phased account of mammal diversity in GLGM and makes a prospect for future research.

关键词： Biodiversity hotspot Eastern Himalaya Gaoligong Mountain Endemism Mammal conservation Hengduan Mountains

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A revision of Dryopteris sect.Diclisodon(Dryopteridaceae)based on morphological and molecular evidence with description of a new species

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Plant Diversity 2022年第2期44卷 181-190页

作者： Zheng-Yu Zuo Ting Zhao Xin-Yu Du yun xiong Jin-Mei Lu De-Zhu Li Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan650201China Kunming College of Life Science University of Chinese Academy of SciencesKunmingYunnan650201China Gongshan Bureau of the Gaoligongshan National Nature Reserve GongshanYunnan673500China

Dryopteris sect.Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia.Here,we carried out morphological and phylogenetic analyses of this section.A new species from southwest China,D.gaoligongensis,is described and illustrated.Dryopteris gaoligongensis resembles D.indonesiana and D.sparsa,but differs by having a creeping rhizome and large 4-pinnate fronds.We also show that D.glabrior Ching&Z.Y.Liu is a distinct species;however,because it is a later homonym of D.glabrior Copel.,it should be renamed D.renchangiana.We conclude that a species previously known as D.nitidula,also an illegitimate homonym,should be recognized with a new name,D.sinonepalensis.We resolve the phylogenetic position of D.yoroii as sister to other sampled species of D.sect Diclisodon.Our phylogenetic analyses confirm the distinctiveness of D.gaoligongensis,D.renchangiana,and D.sinonepalensis.A key to species of D.sect Diclisodon in China is provided.

关键词： Dryopteris gaotigongensis Dryopteris renchangiana Dryopteris sect.Nephrocystis Dryopteris sinonepalensis Molecular phylogeny Nomenclatural novelties

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Multi-GNSS products and services at iGMAS Wuhan Innovation Application Center:strategy and evaluation

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Satellite Navigation 2022年第3期3卷 106-124,I0004页

作者： Xingxing Li Qingyun Wang Jiaqi Wu Yongqiang Yuan yun xiong Xuewen Gong Zhilu Wu School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China

Over the past years the International Global Navigation Satellite System(GNSS)Monitoring and Assessment System(iGMAS)Wuhan Innovation Application Center(IAC)dedicated to exploring the potential of multi-GNSS signals and providing a set of products and services.This contribution summarizes the strategies,achievements,and innovations of multi-GNSS orbit/clock/bias determination in iGMAS Wuhan IAC.Both the precise products and Real-Time Services(RTS)are evaluated and discussed.The precise orbit and clock products have comparable accuracy with the precise products of the International GNSS Service(IGS)and iGMAS.The multi-frequency code and phase bias products for Global Positioning System(GPS),BeiDou Navigation Satellite System(BDS),Galileo navigation satellite system(Galileo),and GLObal NAvigation Satellite System(GLONASS)are provided to support multi-GNSS and multi-frequency Precise Point Positioning(PPP)Ambiguity Resolution(AR).Compared with dual-frequency PPP AR,the time to first fix of triple-frequency solution is improved by 30%.For RTS,the proposed orbit prediction strategy improves the three dimensional accuracy of predicted orbit by 1 cm.The multi-thread strategy and high-performance matrix library are employed to accelerate the real-time orbit and clock determination.The results with respect to the IGS precise products show the high accuracy of RTS orbits and clocks,4–9 cm and 0.1–0.2 ns,respectively.Using real-time satellite corrections,real-time PPP solutions achieve satisfactory performance with horizontal and vertical positioning errors within 2 and 4 cm,respectively,and convergence time of 16.97 min.

关键词： iGMAS Wuhan Innovation Application Center GREAT software Precise orbit determination Precise clock estimation Observation-specific bias Precise point positioning Real-time service

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声纹信号-图形差分场增强和多头自注意力机制的变压器工作状态辨识方法

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应用声学 2024年第1期43卷 119-130页

作者：张寒熊云唐信王枭国网湖南超高压变电公司长沙410000 变电智能运检国网湖南省电力有限公司实验室长沙410000 上海睿深电子科技有限公司上海200237

为提升电力变压器工作状态的智能监测水平,提出声纹信号-图形差分场增强和多头自注意力机制的变压器工作状态辨识方法。基于图形差分场技术将声纹信号映射为二维图像,再借助多头注意力机制的视觉转换器实现图像信息的深层挖掘与状态辨识... 详细信息

为提升电力变压器工作状态的智能监测水平,提出声纹信号-图形差分场增强和多头自注意力机制的变压器工作状态辨识方法。基于图形差分场技术将声纹信号映射为二维图像,再借助多头注意力机制的视觉转换器实现图像信息的深层挖掘与状态辨识,采用梯度加权类激活映射实现分类结果的可解释性分析。搭建了包含变压器4种典型工作状态下的实验模拟测试系统平台,实验结果表明:所提方法不仅能够有效表征变压器声纹信号的状态特征,且分类辨识精度相较于“时频图+引入多头注意力机制的变换网络”与“图形差分场+引入残差模块的卷积神经网络”的常规方法有显著提升,提升约6%,同时也具备较好的鲁棒性,可为电气设备的故障检测研究提供一定参考。

关键词：图形差分场多头自注意力机制变压器状态辨识

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A review of the neptis species group of the genus Lilioceris(Coleoptera:Chrysomelidae:Criocerinae)

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Zoological Systematics 2021年第4期46卷 300-316页

作者： Yuan Xu yun xiong Hongbin Liang Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Gongshan Protection Sub-Bureau Gaoligongshan National Nature ReserveGongshan 673500YunnanChina College of Life Science University of Chinese Academy of SciencesBeijing 100049China

A new species group of the genus Lilioceris Reitter,1913 is proposed and keyed as neptis group,characterized by adults with mesoventral process widened,tuberculate,and horizontally connected with mesoventrite.It includes six species:Lilioceris balyi Chujo,1962,L.cantonensis Heinze,1943 stat.rev.,L.fouana Pic,1932,L.neptis(Weise,1922),L.subpolita(Motschulsky,1861)and L.vietnamica Medvedev,1985.Among them,Lilioceris cantonensis Heinze,1943 is resurrected as a valid species from synonyms of L.neptis(Weise,1922);L.fouana Pic,1932 is transferred from the subgenus Chujoita Monrós,1959 to the subgenus Lilioceris Reitter,1913;L.vietnamica Medvedev,1985 is firstly recorded in China;some misidentifications of former literatures for L.neptis are provided.Redescriptions(if necessary),habitus photographs,geographic distributions,host plants and habitats(if known)are provided for these species.

关键词： Shining leaf beetle taxonomy key genitalia distribution

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康巴地区藏族圈舞形态成因探源

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四川民族学院学报 2024年第2期33卷 96-100页

作者：熊云绯四川民族学院四川康定626001

本文从历史遗存出发,指出康巴地区藏族民间舞蹈多以圈舞形态呈现的原因具有多元性。圈舞是藏族先民古老且常见的舞蹈构图形式的遗存,这种舞蹈形态因情感交流与社会秩序构建需要而形成,因地理环境和农牧业生产方式而造就。围圈舞蹈是多... 详细信息

本文从历史遗存出发,指出康巴地区藏族民间舞蹈多以圈舞形态呈现的原因具有多元性。圈舞是藏族先民古老且常见的舞蹈构图形式的遗存,这种舞蹈形态因情感交流与社会秩序构建需要而形成,因地理环境和农牧业生产方式而造就。围圈舞蹈是多民族文化交流融合的结果;是传统文化尚“圆”审美取向的反映;也是藏族人民宗教信仰和民族性格的体现。

关键词：康巴地区舞蹈构图舞蹈纹彩陶盆圈舞形态锅庄

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从肝论治痴呆的精神行为症状

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中国民间疗法 2024年第2期32卷 10-11,82页

作者：熊赟吴鹏广西中医药大学广西南宁530001 广西中医药大学第一附属医院广西南宁530023

痴呆的精神行为症状指痴呆患者出现知觉、情绪、行为等方面的紊乱,如易怒、抑郁、情感淡漠、睡眠障碍等。该文基于肝与痴呆精神症状的病理、生理联系,探讨从肝论治痴呆的精神行为症状。

关键词：痴呆精神行为症状郁证癫狂体阴用阳从肝论治

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基于图双向选择注意力的公司任职预测算法

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计算机应用与软件 2024年第6期41卷 38-44页

作者：潘文韬熊贇朱扬勇复旦大学计算机科学技术学院上海市数据科学重点实验室上海200438

基于员工与公司潜在的双向选择关系来预测未来员工的去向以及公司的人才引进情况,这些预测信息对于金融、招聘等从业人员在判断公司未来发展和寻找潜在求职者等工作具有指导意义。为了获得节点间的双向选择信息并强化节点信息以增强预... 详细信息

基于员工与公司潜在的双向选择关系来预测未来员工的去向以及公司的人才引进情况,这些预测信息对于金融、招聘等从业人员在判断公司未来发展和寻找潜在求职者等工作具有指导意义。为了获得节点间的双向选择信息并强化节点信息以增强预测效果,在公司与员工及其相关数据构建成的异质图下利用自编码器和三层注意力机制来生成用于任职预测的双向选择向量及节点向量。根据在真实数据集上的实验,该方法在任职预测任务下的预测效果要优于现有方法,同时提高了预测的可解释性。

关键词：异质图元路径自编码器注意力机制深度神经网络职业流动行为

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