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The Earliest Normal Flower from Liaoning Province, China

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Journal of Integrative Plant Biology 2009年第8期51卷 800-811页

作者： Xin wang shaolin Zheng Nanjing Institute of Geology and Palaeontology the Chinese Academy of Sciences Nanjing 210008 China Fairylake Botanical Garden Shenzhen 518004 China Shenyang Institute of Geology and Mineral Resources Shenyang 110032 China

The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofioras. Despite multitudes of angiosperm fossils uncovered, including Archaefructus and Sinocarpus, no bona fide normal flower has been dated to 125 Ma （mega-annum） or older. Here we report Callianthus dilae gen. et sp. nov. from the Yixian Formation （Early Cretaceous） in western Liaoning, China as the earliest normal flower known to date. The flower demonstrates a typical floral organization, including tepals, androecium, and gynoecium. The tepals are spatulate with parallel veins. The stamens have a slender filament, a globular anther, bristles at the anther apex, and in situ round-triangular pollen grains. The gynoecium is composed of two stylate carpels enclosed in a fleshy envelope, and develops into a ＂hip＂ when mature. Since the well-accepted history of angiosperms is not much longer than 125 Ma, Callianthus together with Chaoyangia, Archaefructus and Sinocarpus from the Yixian Formation demonstrate a surprisingly high diversity of angiosperms, implying a history of angiosperms much longer than currently accepted.

关键词： angiosperm bisexual Callianthus Early Cretaceous flower Liaoning perianth Yixian Formation

基于迁移学习的Vision Transformer网络对伽马射线暂现源分类

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中国科学：物理学、力学、天文学 2024年第8期54卷 100-110页

作者：张燕婷马想黄跃刘佳聪熊少林张鹏赵小芸中国科学院高能物理研究所北京100049 中国科学院大学北京101408 同济大学电子与信息工程学院上海201804

伽马射线暂现源包括伽马射线暴(GRB)、软伽马射线重复暴(SGR)等极端天体爆发现象,主要由空间伽马射线监测器(例如GECAM卫星)开展探测研究,是天文学重要的研究前沿.另外,太阳活动和复杂的空间环境也会在空间伽马射线监测器产生各类爆发事... 详细信息

伽马射线暂现源包括伽马射线暴(GRB)、软伽马射线重复暴(SGR)等极端天体爆发现象,主要由空间伽马射线监测器(例如GECAM卫星)开展探测研究,是天文学重要的研究前沿.另外,太阳活动和复杂的空间环境也会在空间伽马射线监测器产生各类爆发事件(统称为触发).在诸多触发事件中对GRB和SGR进行快速分类识别是开展后续物理研究的重要前提.传统的分类研究常使用贝叶斯方法,利用多个特征信息建模计算各个类别概率,但其需要大量的先验知识与合理的模型设想,且不同卫星间的传统分类模型面临迁移难、适用窄等问题.为高效快速地对触发进行分类,本文提出利用Vision Transformer网络,基于迁移学习和单流多模态的思想,使用较少的计算资源和数据对触发进行分类.本文将该方法应用于GECAM触发数据,实验结果表明,模型在测试集中准确率达到了89%,且模型能够理解类别间的区分与相似性.本文结果表明,这种新的方法对于伽马射线暂现源以及其他天文现象的分类具有良好应用前景.

关键词：伽马射线暂现源迁移学习触发分类

Complete Parasitic Capacitance Model of Photovoltaic Panel Considering the Rain Water

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Chinese Journal of Electrical Engineering 2017年第3期3卷 77-84页

作者： shaolin Yu Jianing wang Xing zhang Fei Li School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

Common mode current suppression is important to grid-connected photovoltaic(PV)systems and depends strongly on the value of the parasitic capacitance between the PV panel and the *** parasitic capacitance models have been proposed to evaluate the magnitude of the effective parasitic ***,the proposed model is only for the PV panels under dry and clean environmental *** dependence of rain water on the capacitance is simply described rather than analyzing in ***,the effects of water are addressed quite differently in ***,this paper gives complete parasitic capacitance model of the PV panel considering the rain *** effect of the water on the capacitance is systematically investigated through 3D finite element(FE)electromagnetic(EM)simulations and ***,it is clarified how the water affects the parasitic capacitance and methods of minimization of the capacitance are proposed.

关键词： Parasitic capacitance photovoltaic panel water 3D FE EM analysis electromagnetic field

基于混沌粒子群的双馈风电机组LVRT实测建模及暂态参数辨识

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中国电力 2024年第8期57卷 75-84页

作者：李丹秦世耀李少林贺敬可再生能源并网全国重点实验室(中国电力科学研究院有限公司) 北京100192

高准确度仿真模型是进行大规模风电并网暂态稳定分析的基础,然而双馈风电机组(DFIG)控制策略与参数属于技术秘密难以获取,模型仿真准确性难以保证。针对DFIG故障暂态精确建模难题,提出了基于实测数据的DFIG建模及参数辨识方法。首先,基... 详细信息

高准确度仿真模型是进行大规模风电并网暂态稳定分析的基础,然而双馈风电机组(DFIG)控制策略与参数属于技术秘密难以获取,模型仿真准确性难以保证。针对DFIG故障暂态精确建模难题,提出了基于实测数据的DFIG建模及参数辨识方法。首先,基于电力系统综合稳定程序(PSASP)中DFIG模型及控制结构,建立低电压穿越(LVRT)控制数学模型并分析故障暂态过程,明确LVRT暂态控制核心参数。其次,基于DFIG的LVRT部分现场实测工况数据,利用混沌粒子群算法实现了DFIG故障暂态控制参数辨识。最后,基于剩余实测工况数据进行辨识参数准确性分析与校验,仿真验证了所提参数辨识方法的有效性及准确性。所提方法辨识结果泛化能力强、准确度高,具有较高的工程应用价值。

关键词：双馈风电机组低压穿越参数辨识实测数据混沌粒子群

铸态Cu-1.16Ni-0.36Cr合金热变形行为及热加工图

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材料导报 2024年第2期38卷 220-227页

作者：孙文明李韶林宋克兴王强松丁宗业朱莹莹河南科技大学材料科学与工程学院河南洛阳471023 河南科技大学河南省有色金属材料科学与加工技术重点实验室河南洛阳471023 河南省科学院郑州450052 有研科技集团有限公司有色金属材料制备加工国家重点实验室北京100088 有研工程技术研究院有限公司北京101407 佛山科学技术学院机电工程与自动化学院广东佛山528225

利用Gleeble-1500型热模拟试验机,研究了Cu-1.16Ni-0.36Cr合金在变形量为50%、变形温度为750~950℃、变形速率为0.01~10 s^(-1)下的热压缩变形行为,建立该合金热变形的本构方程和热加工图。结果表明:Cu-1.16Ni-0.36Cr合金在700~900℃的... 详细信息

利用Gleeble-1500型热模拟试验机,研究了Cu-1.16Ni-0.36Cr合金在变形量为50%、变形温度为750~950℃、变形速率为0.01~10 s^(-1)下的热压缩变形行为,建立该合金热变形的本构方程和热加工图。结果表明:Cu-1.16Ni-0.36Cr合金在700~900℃的变形温度下以动态回复为主,在950℃下发生完全的动态再结晶。通过真应力应变曲线得到了该合金热变形的本构方程和热加工图。根据应变对流变应力的影响对本构方程进行修正,通过修正后的回归方程对流变应力进行模拟,模拟结果与实验结果吻合。热加工图表明,该合金适宜的热变形工艺参数为900~950℃和0.1~1 s^(-1),其中950℃和1 s^(-1)变形条件下组织状态最佳,为晶粒细小均匀的等轴晶。

关键词： Cu-Ni-Cr合金热压缩变形本构方程热加工图动态再结晶

考虑保护启动信息的电网故障诊断解析模型及告警方法

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现代电力 2024年第3期41卷 401-411页

作者：曹祺肖仕武焦邵麟周放歌新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 广东电网有限责任公司电力调度控制中心广东省广州市510032

当高压电网发生故障时,在关键保护或断路器元件出现误动或信息误报、漏报时,现有故障诊断解析模型会出现误判。为解决这一问题,提出考虑保护启动信息的电网故障诊断解析模型及告警方法。首先,在传统故障诊断解析模型的基础上,增加了保... 详细信息

当高压电网发生故障时,在关键保护或断路器元件出现误动或信息误报、漏报时,现有故障诊断解析模型会出现误判。为解决这一问题,提出考虑保护启动信息的电网故障诊断解析模型及告警方法。首先,在传统故障诊断解析模型的基础上,增加了保护期望启动状态与实际状态差异值,构建了考虑保护启动信息的电网故障诊断适应度函数,并基于粒子群算法进行寻优计算,得到故障元件,解决了关键保护或断路器元件出现误动作或信息误报、漏报时诊断错误的问题。然后,基于所得到的故障元件,利用保护启动信息生成保护启动层级图,对启动异常的保护进行告警。最后,利用推理链的方法对整个故障过程进行完整解析。新解析模型的灵敏度和准确度与传统方法相比有较大提升,且考虑保护启动信息的保护告警方法能对启动信息异常的保护进行提前告警,具有良好的应用前景。

关键词：故障诊断解析模型高压电网启动信息保护告警

A new species of Lepidopteris discovered from the Upper Permian of China with its stratigraphic and biologic implications

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Chinese Science Bulletin 2012年第24期57卷 3603-3609,3661页

作者： zhang Yi ZHENG shaolin NAUGOLNYKH Serge V College of Paleontology Shenyang Normal UniversityShenyang 110034China Geological Institute Russian Academy of SciencesMoscow 119017Russia

A new species Lepidopteris baodensis *** to the family Peltaspermaceae and represented by two ultimate pinnae in the collection under study,was recently discovered at the Baijiagou of Baode,Shanxi,China,from the Upper Permian Sunjiagou *** lower surface of the ultimate rachis,the midrib and secondary veins is covered with triangular,trapezoid,rounded,or ligulate subepidermal swellings,which show different natures from intercalary *** is one of typical elements of the Late Permian Euramerican *** Schimper erected the genus Lepidopteris in 1869,the entire epidermal structure of subepidermal swellings had been *** new species *** clearly showing the distinguished epidermal structure of subepidermal swellings,not only enlarges and supplements our knowledge in biology and taxonomy of Lepidopteris as well as the Upper Permian stratigraphy of China,but also provides an opportunity to understand the relationship between Euramerican floras and Cathaysian floras in paleoclimatic,paleoenvironmental and paleogeographic context.

关键词：生物学意义上二叠统地层学中国新种表皮结构欧美植物群华夏植物群

An Undercover Angiosperm from the Jurassic of China

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 895-902页

作者： ZHENG shaolin wang Xin Palaeontological Institute Shenyang Normal University Shenyang 110034 China Shenyang Center of Geological Survey and Institute of Geology and Mineral Resources. Ministry of National Land and Resources Shenyang 110034 China Nanjing Institute of Geology and Palaeontolog）. Nanjing 210008 China Fairylake Botanical Garden Shenzhen 518004 China

Searching for early angiosperms is a riveting activity in botany because it helps to resolve the phyiogenetic relationships among seed plants and among angiosperms themselves. One of the challenges for this job is what the target fossils look like. Most possibly early angiosperms may elude our scrutiny with gymnospermous appearances. This possibility becomes a reality in a Jurassic plant, Solaranthus gen. nov, which bears a peltaspermalean appearance and enclosed ovules. According to knowledge available hitherto, the latter feature makes it an angiosperm. However, such a feature is more likely to be eclipsed by its gymnospermous appearance. The early age and unexpected character assemblage of Solaranthus urge for a fresh look on the assumed-simple relationship between angiosperms and gymnosperms. Its resemblance to the order Peltaspermales favors the Mostly Male Theory.

关键词： bisexual flower Jurassic angiosperms Peltaspermales Mostly Male Theory

Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China

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Acta Geologica Sinica(English Edition) 2007年第3期81卷 357-364页

作者： zhang Lijun YANG Yajun zhang Lidong GUO Shengzhe wang Wuli ZHENG shaolin Shenyang Institute of Geology and Mineral Resources Ministry of Land and Resources Shenyang Liaoning 110032

Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of the formation in the Dachengzi, Chaoyang, *** and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous.

关键词： division correlation precious fossil-bearing beds Lower Cretaceous JiufotangFormation western Liaoning