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速度对低成本GNSS接收机互操作信号的性能影响
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作者 张家同 崔先强 +3 位作者 朱永兴 蔡昌盛 张鹏飞 甘雨 《大地测量与地球动力学》 CSCD 北大核心 2024年第6期577-583,共7页
收集低成本接收机3种速度区间路段的动态数据,分析多系统互操作信号B1C/L1/E1和B2a/L5/E5a在不同速度区间的数据接收能力、数据质量和导航定位性能。结果表明:1)随着速度加快,互操作信号的数据接收能力逐渐变差,其中BDS-3可以保持较多... 收集低成本接收机3种速度区间路段的动态数据,分析多系统互操作信号B1C/L1/E1和B2a/L5/E5a在不同速度区间的数据接收能力、数据质量和导航定位性能。结果表明:1)随着速度加快,互操作信号的数据接收能力逐渐变差,其中BDS-3可以保持较多的可见卫星数,平均在9颗以上;B1C/L1/E1数据完整率较优,但更容易发生数据中断。2)随着速度加快,互操作信号载噪比降低、周跳比增加,而伪距与载波相位噪声及多路径效应受速度影响较弱,其中B1C/L1/E1载波相位噪声与多路径效应值较小。3)载体速度对定位精度的影响没有明显的规律,速度与环境遮挡程度综合影响定位精度,其中多系统互操作信号组合定位较单系统定位性能提升较多;BDS-3在中低速度区间精度较高,PPP精度较其他系统高17%以上。 展开更多
关键词 BDS-3 数据质量分析 互操作信号 导航定位 PPP
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灌区节水改造及渠道防冻胀的设计研究 被引量:2
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作者 卞丙磊 《科学技术创新》 2023年第3期161-164,共4页
以微山县灌区小型农田水利工程为例,探究了渠道及渠系建筑物的节水改造方案,以及改造过程中的防冻胀设计要点。在节水改造方面,采用全断面C20混凝土预制块衬砌施工方案,有效解决了渠道流水的渗漏问题,节水效果明显。开敞式矩形断面结构... 以微山县灌区小型农田水利工程为例,探究了渠道及渠系建筑物的节水改造方案,以及改造过程中的防冻胀设计要点。在节水改造方面,采用全断面C20混凝土预制块衬砌施工方案,有效解决了渠道流水的渗漏问题,节水效果明显。开敞式矩形断面结构的分水闸和竖井式倒虹吸管在提高水资源利用率方面也有积极作用;在防冻胀设计方面,在渠道基础上使用砂砾石垫层提高其抗冻胀性能,同时设计了弧底梯形断面解决因为应力集中而导致的胀裂问题,切实保障了灌区渠道在冬季的使用安全。 展开更多
关键词 节水改造 渠道防冻胀 水闸
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Taxonomical notes on selected freshwater fish species described from northern and central Vietnam (Cypriniformes: Balitoridae, Cobitidae, Cyprinidae, Nemacheilidae; Perciformes: Channidae, Osphronemidae; Synbranchiformes: Mastacembelidae) 被引量:2
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作者 Marco Endruweit 《Zoological Research》 CAS CSCD 北大核心 2014年第2期142-159,共18页
Selected,little known taxa of northern and central Vietnamese freshwater fish species are reviewed.Nomenclatural acts are taken:Hemibarbus lehoai is placed in synonymy of H.maculatus,Paracobitis hagiangensis in synony... Selected,little known taxa of northern and central Vietnamese freshwater fish species are reviewed.Nomenclatural acts are taken:Hemibarbus lehoai is placed in synonymy of H.maculatus,Paracobitis hagiangensis in synonymy of Schistura caudofurca.A neotype of Micronemacheilus bacmeensis is assigned.The name Channa hanamensis is treated as a nomen nudum.Two labeonine species described from China are nomenclaturally affected:Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition;the specific epithet of Sinigarra napoense is corrected to napoensis. 展开更多
关键词 New species Ichthyology Taxonomy Nomenclature VIETNAM
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中医三联疗法治疗2型糖尿病患者的临床效果研究 被引量:7
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作者 陈斌 张苍 《实用临床医药杂志》 CAS 2019年第5期20-22,26,共4页
目的评价中医三联疗法治疗2型糖尿病患者的临床效果。方法选取本院180例2型糖尿病患者,按入院顺序尾号单双数分为对照组90例与观察组90例。对照组实施常规西医疗法,观察组给予中医三联疗法,比较2组患者血糖控制效果。结果观察组治疗后... 目的评价中医三联疗法治疗2型糖尿病患者的临床效果。方法选取本院180例2型糖尿病患者,按入院顺序尾号单双数分为对照组90例与观察组90例。对照组实施常规西医疗法,观察组给予中医三联疗法,比较2组患者血糖控制效果。结果观察组治疗后空腹血糖、餐后2 h血糖、糖化血红蛋白水平低于对照组(P <0. 05);一般自我效能感量表(GSES)评分高于对照组,焦虑、抑郁情绪评分低于对照组,差异均有统计学意义(P <0. 05)。结论中医三联疗法治疗2型糖尿病能显著控制血糖。 展开更多
关键词 中医三联疗法 2型糖尿病 血糖控制 一般自我效能感量表 糖化血红蛋白
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加味清眩降压汤在改善老年高血压中医证候和眩晕症状中的作用 被引量:5
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作者 陈斌 冯志刚 《现代中医药》 CAS 2019年第2期50-53,共4页
目的分析加味清眩降压汤在改善老年高血压中医证候和眩晕症状中的作用。方法选取2015年7月~2017年7月本院收治的99例老年高血压眩晕患者,随机分为对照组(49例)应用强力定眩片治疗,治疗组(50例)应用加味清眩降压汤。比较两组患者治疗前... 目的分析加味清眩降压汤在改善老年高血压中医证候和眩晕症状中的作用。方法选取2015年7月~2017年7月本院收治的99例老年高血压眩晕患者,随机分为对照组(49例)应用强力定眩片治疗,治疗组(50例)应用加味清眩降压汤。比较两组患者治疗前后收缩压、舒张压水平及治疗后中医证候疗效、眩晕症状疗效的差异。结果治疗后,对照组收缩压较治疗前明显下降(P <0. 05),而舒张压与治疗前比较,并无明显差异(P> 0. 05)。与治疗前相比,治疗组治疗后收缩压和舒张压均明显下降,且治疗后血压水平较对照组明显下降(P <0. 05)。治疗组中医证候治疗总有效率为92. 00%,较对照组的71. 43%明显升高(P <0. 05)。治疗组眩晕症状治疗总有效率为94. 00%,较对照组的75. 51%明显升高(P <0. 05)。结论加味清眩降压汤可有效改善老年高血压中医证候及眩晕症状,可明显减轻临床症状,且具有良好的降压效果,值得临床应用。 展开更多
关键词 高血压 老年 加味清眩降压汤 中医证候 眩晕症状 疗效
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六君子汤合丹参饮治疗气虚血瘀证冠心病临床研究 被引量:2
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作者 陈斌 赵红利 《现代中医药》 CAS 2019年第3期42-45,共4页
目的分析探讨六君子汤合丹参饮对气虚血瘀证冠心病患者经皮冠状动脉介入治疗术后支架内再狭窄的影响。方法选取我院于2015年1月~2017年1月期间收治的95例气虚血瘀证冠心病患者,按照随机数字表法将所有患者随机分为对照组和治疗组两组,... 目的分析探讨六君子汤合丹参饮对气虚血瘀证冠心病患者经皮冠状动脉介入治疗术后支架内再狭窄的影响。方法选取我院于2015年1月~2017年1月期间收治的95例气虚血瘀证冠心病患者,按照随机数字表法将所有患者随机分为对照组和治疗组两组,所有患者均采取经皮冠状动脉介入术进行治疗,其中对照组患者均给予硝酸酯类、他汀类、阿司匹林、氯吡格雷等药物进行治疗,而治疗组患者则在此基础上联合使用六君子汤合丹参饮进行治疗,所有患者均持续治疗3个月。记录两组患者治疗前后的气虚积分和证候积分、支架再狭窄率以及血瘀积分等指标,比较两组患者的临床治疗效果。结果两组患者治疗前的中医证候积分和气虚证积分、血瘀证积分等并无明显差异(均P>0.05);两组患者经过治疗后的中医证候积分和血瘀证积分均显著优于本组治疗前(均O<0.05);治疗组患者治疗后的气虚证积分显著优于本组治疗前,并且该组患者治疗后的中医证候积分和血瘀证积分均显著优于同期对照组患者(均P<0.05)。治疗组患者的再狭窄发生率为4.17%,显著低于对照组患者的19.15%(χ^2=9.374,P<0.05)。治疗组患者的总有效率为95.83%,显著高于对照组患者的87.23%(χ^2=11.444,P<0.05)。结论对气虚血瘀证冠心病患者经皮冠状动脉介入治疗术后采取六君子汤合丹参饮进行治疗能够有效改善其支架内再狭窄情况,治疗效果显著,值得在临床上加以推广运用。 展开更多
关键词 冠心病 六君子汤 介入治疗 支架 气虚血瘀
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Schistura sexnubes, a new diminutive river loach from the upper Mekong basin, Yunnan Province, China (Teleostei: Cypriniformes: Nemacheilidae)
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作者 Marco Endruweit 《Zoological Research》 CAS CSCD 北大核心 2014年第1期59-66,共8页
An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readil... An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters: 8+8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth (7.6%-9.6% SL; respectively caudal peduncle 1.76-1.95 times longer than deep), a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy. 展开更多
关键词 Schistura sexnubes New species Mekong basin Nemacheilidae Yunnan
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Four new records of fish species (Cypriniformes: Nemacheilidae, Balitoridae; Characiformes: Prochilodontidae) and corrections of two misidentified fish species (Tetraodontiformes: Tetraodontidae; Beloniformes: Belonidae) in Yunnan, China
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作者 Marco Endruweit 《Zoological Research》 CAS CSCD 北大核心 2014年第1期51-58,共8页
In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura arnplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe Rive... In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura arnplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe River subbasins, Mekong basin; the prochilodontid Prochilodus lineatus (Valenciennes, 1837), the balitorid Vanmanenia serrilineata Kottelat, 2000, and the tetraodontid Monotrete turgidus Kottelat, 2000, from Nanlahe River subbasin, Mekong basin; the balitorid Beaz^fortia daon (Mai, 1978), and the belonid Xenentodon canciloides (Bleeker, 1854), both, from Black River subbasin, Red River basin. The freshwater puffer M. turgidus and the needlefish ,E canciloides have been previously misidentified as Tettraodon leiurus (Bleeker, 1950) and Tylosurus strongylurus (van Hasselt, 1823), respectively. 展开更多
关键词 New record MISIDENTIFICATION Mekong basin Red River YUNNAN
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Schistura megalodon species nova, a new river loach from the Irrawaddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae)
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作者 Marco Endruweit 《Zoological Research》 CAS CSCD 北大核心 2014年第5期353-361,共9页
A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yuunan Province, China. The following combination of diagnostic char... A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yuunan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a broad and distinct basicaudal bar with forward extensions. 展开更多
关键词 Schistura megalodon Irrawaddy Dehong YUNNAN
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Bridging from the Sequence to Architecture: Graft Copolymers Engineering via Successive Latent Monomer and Grafting-from Strategies 被引量:2
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作者 Yajie Zhang Xiaohuan Cao +4 位作者 Yang Gao Yujie Xie Zhihao Huang Zhengbiao Zhang Xiulin Zhu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2021年第5期1273-1280,共8页
The on-demand building copolymer structures,from sequence to architecture,is crucial in understanding the relation between pol-ymer structure and property,meanwhile motivating the innovation of polymer hierarchy.Howev... The on-demand building copolymer structures,from sequence to architecture,is crucial in understanding the relation between pol-ymer structure and property,meanwhile motivating the innovation of polymer hierarchy.However,the challenge is conspicuous for,complicated polymer structures from inherently intricate polymerization.In this work,copolymers with tailored grafting density and distributions were achieved using successive latent monomer and grafting-from strategies.The hydroxyl group functionalized fu-ran/maleimide adduct(FMOH)was selected as the latent monomer for RAFT polymerization of an array of copolymers with tailored localization of hydroxyl group along the main chain.The hydroxyI group further initiated the ring opening polymerization(ROP)of L-lactide or ε-caprolactone,resulting in a library of multicomponent copolymers via grafting-from strategy.The initiating efficiency reached to-100% with variable molecular weight(21300-58600 Da)and narrow distributions(Ð_(M)<1.25),indicating that such graft copolymers possessed controlled density and distribution of side chains as its linear template.The investigation on thermal properties of the well-defined graft copolymers implied that the precise tailoring over copolymer structures at the molecule level could lead to tunable chemical/physical properties.This work bridged polymer from sequence to architecture,unveiled a new meth-od in creating graft copolymers with programmable structures and provided the insight into the structure/property relationship. 展开更多
关键词 Sequence determination Polymers Latent Monomer Polymerization MALEIMIDE
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