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西藏科技 2009年第4期 58-60页

作者：陈忠旭西藏天路有限公司西藏拉萨850000

混凝土外加剂能有效地改善混凝土的性能、提高工程质量、提高技术经济效益,因而受到国内外的普遍重视。本文简要介绍了混凝土外加剂在西藏发展及应用。

关键词：混凝土外加剂西藏发展应用

Genome sequencing of Sitopsis species provides insights into their contribution to the B subgenome of bread wheat

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Plant Communications 2023年第4期4卷 208-224页

作者： Yuxin Yang Licao Cui Zefu Lu Guangrong Li Zujun Yang Guangyao Zhao Chuizheng Kong Danping Li Yaoyu chen Zhencheng Xie zhongxu chen Lichao Zhang Chuan Xia Xu Liu Jizeng Jia Xiuying Kong State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Center for Informational Biology School of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengdu 610054China Triticeae Research Institute Sichuan Agricultural UniversityChengdu 611130China

Wheat(Triticum aestivum,BBAADD)is an allohexaploid species that originated from two polyploidization *** progenitors of the A and D subgenomes have been identified as Triticum urartu and Aegilops tauschii,*** research suggests that Aegilops speltoides is the closest but not the direct ancestor of the B ***,whether *** has contributed genomically to the wheat B subgenome and which chromosome regions are conserved between *** and the B subgenome remain ***,we assembled a high-quality reference genome for ***,resequenced 53 accessions from seven species(Aegilops bicornis,Aegilops longissima,Aegilops searsii,Aegilops sharonensis,***,Aegilops mutica[*** muticum],and Triticumdicoccoides)and revealed their genomic contributions to the wheat B *** results showed that centromeric regions were particularly conserved between Aegilops and Triticum and revealed 0.17 Gb of conserved blocks between *** and the B *** classified five groups of conserved and non-conserved genes between Aegilops and Triticum,revealing their biological characteristics,differentiation in gene expression patterns,and collinear relationships between *** and the wheat B *** also identified gene families that expanded in *** during its evolution and 789 genes specific to *** genes can serve as genetic resources for improvement of adaptability to biotic and abiotic *** newly constructed reference genome and large-scale resequencing data for Sitopsis species will provide a valuable genomic resource for wheat genetic improvement and genomic studies.

关键词： Aegilops Sitopsis polyploid wheat B subgenome conserved blocks

Profile of Dr. Songlin chen

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Science China Life Sciences 2024年第10期67卷 2062-2063页

作者： chen, Songlin Yellow Sea Fisheries Res Inst Qingdao Peoples R China

For decades, Dr. chen has been engaged in fish germplasm preservation, sex control and research focusing on molecular breeding for disease resistance. He discovered the first sex-specific molecular marker of fish(chen et al., 2007),deciphered the first fish genome(Chinese tongue sole) in China, revealed the sex determination mechanism in fish(chen et al., 2014), and created molecular sex control technology. He also discovered the molecular mechanism of metamorphosis in flatfish(Shao et al., 2017) and developed China's first fish disease-resistant breeding gene chip, “YUXIN No.1”.

关键词： TURBOT SCOPHTHALMUS-MAXIMUS GENOMIC SELECTION JAPANESE FLOUNDER SEX-CHROMOSOME CELL-LINE CRYOPRESERVATION EVOLUTION EMBRYOS

Effect of Reclamation on the Groundwater-Lake Water Interaction in chen Lake

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Journal of Earth Science 2024年第3期35卷 1083-1086页

作者： Kun Lei Teng Ma Liuzhu chen Zhenxing Li Yu chen School of Environmental Studies State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan 430078China

0 INTRODUCTION To relieve the short supply of suitable land for residing,cultivating,and commerce,it is accepted to reclaim land from lakes,river estuaries,and coastal regions in many countries(Mancini et al.,2020).The large-scale reclamation activities have an irreversible effect on the mico-geomorphology and hydrodynamic system of seasonally flooded areas(Zhang et al.,2019;Yu et al.,2018).For example,coastal regions reclaimed extended the groundwater flow paths,as well as created groundwater level rise,resulting in water-logging in the reclaimed area(Hu et al.,2008).Similar changes in groundwater flow systems may alter groundwater-lake water interactions,and it can ultimately affect the water cycle in the lake ***,such detailed studies are presently *** addition,natural exchanges between the lake and groundwater systems can be strongly affected by physical hydrological processes(Javadzadeh et al.,2020),chemical properties(Kamtchueng et al.,2015),and bioto behavior(Hancock et al.,2005).

关键词： groundwater coastal logging

层厚/支撑角度及后处理对SLA零件性能的影响

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中国塑料 2017年第9期31卷 91-96页

作者：郭亮陈忠旭张庆茂冯加模华南师范大学广东省微纳光子功能材料与器件重点实验室广东广州510006 广州市光机电技术研究院广东广州510663

采用VisiJet~SL Black型光敏树脂,从成型过程及后处理工艺出发,研究了切片层厚、支撑角度对成型件尺寸精度和表面精度的影响及二次固化时间对拉伸性能的影响。结果表明,支撑角度越接近45°,试样尺寸精度越高,小支撑角度大层厚试样会... 详细信息

采用VisiJet~SL Black型光敏树脂,从成型过程及后处理工艺出发,研究了切片层厚、支撑角度对成型件尺寸精度和表面精度的影响及二次固化时间对拉伸性能的影响。结果表明,支撑角度越接近45°,试样尺寸精度越高,小支撑角度大层厚试样会出现上表面隆起现象;层厚越大,试样表面越粗糙;二次固化后的拉伸强度在9.33~22.84 MPa之间,断裂机制均为脆性断裂,二次固化时间为200min时,材料的拉伸强度为20.24 MPa,塑性最好,断裂伸长率最大为3.80%;二次固化时间为250min时,拉伸强度最大为22.84 MPa,但塑性降低。

关键词：光固化三维打印成型精度力学性能

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基于测地线的航天器集群隐蔽机动轨迹规划

宇航学报 2024年第4期45卷 513-522页

作者：王璟贤白玉铸陈致钧郑中旭赵勇陈小前国防科技大学空天科学学院长沙410073 军事科学院北京100091

针对航天器集群隐蔽机动问题,提出一种基于测地线的航天器集群轨迹规划方法。该方法将轨迹规划问题抽象到微分流形拓扑空间中,通过数学定义赋予空间结构度量。首先将集群的运动约束、避撞约束以及隐蔽构型约束等非凸约束集成到度量中,... 详细信息

针对航天器集群隐蔽机动问题,提出一种基于测地线的航天器集群轨迹规划方法。该方法将轨迹规划问题抽象到微分流形拓扑空间中,通过数学定义赋予空间结构度量。首先将集群的运动约束、避撞约束以及隐蔽构型约束等非凸约束集成到度量中,避免增加系统维度的同时无需进行约束凸化处理。进一步定义了一个依赖于流形度量的目标泛函,利用同伦变换将泛函局部极值问题转为偏微分方程求解问题。数值仿真结果表明,相比于模型预测-序列凸规划算法,该方法在解决了隐蔽机动非凸多约束问题的同时,具有不依赖于初始猜想、集群内部隐蔽覆盖性高和系统控制输入小的特点,能够为航天器集群提供有效的隐蔽机动轨迹。

关键词：航天器集群测地线隐蔽机动轨迹规划黎曼度量

Meridional deflection of global eddy propagation derived from tandem altimetry: Mechanism and implication

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Science China Earth Sciences 2024年第3期67卷 811-825页

作者： Ge chen Xiaoyan chen Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQindao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQindao 266237China

A common view on meridional deflection of eddy propagation is poleward for cyclones and equatorward for anticyclones. This widely accepted polarity-sensitive pattern has been increasingly undermined given that it is systematically violated on both zonal and regional scales as recently reported. Here, we approach the problem by exploring these violations in terms of eddy effects of spatiotemporal geostrophy, thermal fading, and flow dragging, yielding the following main conclusions.(1) The polarity-dependent deflection discrepancy is a pseudo feature resulting from a biased fit to the normalized eddy tracks which are spatially asymmetric(though azimuthally symmetric) between the two signs;Instead, the primary pattern of eddy deflection appears to be geographically correlated and polarity independent.(2) Geostrophic adjustment plays a critical role in defining the meridional movement of an eddy. Specifically, a consistent poleward(equatorward) trajectory bending of spatially(temporally) ageostrophic eddies is observed irrespective of their polarity.(3) The mechanism of eddy deflection is also determined by its zonal propagation direction. Westward propagating eddies are substantially affected by thermal fading, while opposite ones by flow dragging. A realistic and comprehensive understanding of eddy deflection mechanisms serves as a significant contribution to the prediction of eddy trajectory, and the protection of ocean environment.

关键词： Mesoscale eddies Eddy propagation Eddy meridional deflection Satellite observation Geostrophic adjustment

A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： Xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： chen Jinyang WANG Xuhua chen Xian Research Institute for National Defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for *** this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm ***, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network

Two-stage Planning Method for Energy Router Considering Its Optimal Operation in Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 605-616页

作者： Meifu chen Mingchao Xia Qifang chen School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

An energy router can effectively optimize the network loss and power quality of distribution networks. The optimal configuration of the energy router is relatively complex because issues dynamically influence each other, such as the location of the energy router, optimal number and capacity of its ports, and building new distribution lines for the ports. Presently, there has been very few research studies on the practical problems for the energy router. In this paper, a planning model of an energy router combined with the distribution network is established, which fully exploits the active and reactive power control abilities of the energy router to optimize the operation of the grid. The configuration problem is decoupled into two stages. The upper layer determines the location of the energy router and the parameters of the candidate new distribution lines for the ports. The lower layer calculates the optimal configuration of the energy router by minimizing the total annual cost. Because of the same rated bus voltage in the distribution network, the existing structure of the energy router is changed to be more applicable for the distribution network, and then the power flow model of the energy router is also modified. Due to the nonlinearity of the model, the planning model is converted into a mixed-integer second-order cone model to solve efficiently. In addition, some core factors influencing the optimal scheme of the energy router are also analyzed in this paper. Simulation results show that the optimal scheme of the energy router can significantly improve the economic deployment of the energy router, and optimize the network loss and power quality of the distribution network.

关键词： Capacity allocation distribution network energy router optimal operation