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Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental validation.The experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly analyzed.The cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation formed.The formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of cavitation.In addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid change.This phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

OcBSA:An NGS-based bulk segregant analysis tool for outcross populations

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Molecular Plant 2024年第4期17卷 648-657页

作者： Lingkui zhang Yanfeng Duan Zewei zhang Lei zhang Shumin Chen Chengcheng Cai Shaoguang Duan kang zhang Guangcun Li Feng Cheng State Key Laboratory of Vegetable Biobreeding Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture and Rural AffairsKey Laboratory of Biology and Genetic Improvement of Tuber and Root Crop of Ministry of Agriculture and Rural AffairsSino-Dutch Joint Laboratory of Horticultural GenomicsInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081China

Constructing inbred lines for self-incompatible species and species with long generation times is challenging,making the use of F1 outcross/segregating populations the main strategy for genetic studies of such species.However,there is a lack of dedicated algorithms/tools for rapid quantitative trait locus(QTL)mapping using the F1 populations.To this end,we have designed and developed an algorithm/tool called OcBSA specifically for QTL mapping of F1 populations.OcBSA transforms the four-haplotype inheritance problem from the two heterozygous diploid parents of the F1 population into the two-haplotype inheritance problem common in current genetic studies by removing the two haplotypes from the heterozygous parent that do not contribute to phenotype segregation in the F1 population.Testing of OcBSA on 1800 simulated F1 populations demonstrated its advantages over other currently available tools in terms of sensitivity and accuracy.In addition,the broad applicability of OcBSA was validated by QTL mapping using seven reported F1 populations of apple,pear,peach,citrus,grape,tea,and rice.We also used OcBSA to map the QTL for flower color in a newly constructed F1 population of potato generated in this study.The OcBSA mapping result was verified by the insertion or deletion markers to be consistent with a previously reported locus harboring the ANTHOCYANIN 2 gene,which regulates potato flower color.Taken together,these results highlight the power and broad utility of OcBSA for QTL mapping using F1 populations and thus a great potential for functional gene mining in outcrossing species.For ease of use,we have developed both Windows and Linux versions of OcBSA,which are freely available at:https://***/Bioinformaticslab/OcBSA.

关键词： outcross BSA self-incompatible F1 population QTL mapping potato

Polarization-space joint mainlobe jamming countermeasure technique based on divided dimensions

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Journal of Systems Engineering and Electronics 2022年第3期33卷 594-599页

作者： SHA Minghui MAO Erke zhang kang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Radio Measurement Beijing 100854China

In order to solve the problem that the traditional space jamming countermeasure cannot deal with the mainlobe self-protecting jammings,a polarization-space joint mainlobe jamming countermeasure technique based on divided dimensions is proposed.Specifically,the digital beam of each row and column is firstly formed by using dual polarization digital receiving in multi-channel.Then,the polarization-space joint cancellation in both azimuth and elevation dimensions is carried out based on the polarization-space joint difference between the target echo and the jamming,as well as the divided dimension feature of the row and column beams.Finally,the sum and difference beams of the full array in the elevation or azimuth dimension are formed by the beams after jamming cancelling,and the monopulse angle measurement is further employed to obtain target angles.The effectiveness of the proposed technique is verified by simulations,indicating that the self-protecting jamming and multiple mainlobe following jammings can be both cancelled simultaneously with the angle measurement unchanged.

关键词： mainlobe jamming countermeasure self-protecting jamming following jamming polarization-space joint cancelling dimension-divided angle measurement

基于多窗口识别的多波长光信号峰值实时检测系统

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红外与激光工程 2024年第5期53卷 198-207页

作者：张康姜海明谢康广东工业大学机电工程学院精密电子制造技术与装备国家重点实验室广东广州510006

波分复用(Wavelength Division Multiplexing,WDM)作为光纤通信系统的核心技术之一,为多个波长光信号的复用和传输提供了强有力的解决方案,对复用光信号的解复用和识别是WDM系统需解决的重要问题之一。文中研制了一种针对多波长光信号... 详细信息

波分复用(Wavelength Division Multiplexing,WDM)作为光纤通信系统的核心技术之一,为多个波长光信号的复用和传输提供了强有力的解决方案,对复用光信号的解复用和识别是WDM系统需解决的重要问题之一。文中研制了一种针对多波长光信号峰值的实时检测系统,用于实时检测多波长光信号的峰值功率。首先,设计并研制了光纤法布里-珀罗可调谐滤波器(FFP-TF)的驱动控制器和微弱光信号探测器,分别控制FFP-TF的驱动电压使其滤出特定波长的光信号和对滤出光信号的功率进行实时探测;其次,对于光电探测器中实时探测的光信号功率,设计了一种基于多窗口识别的峰值检测方法,使用三个针对波形不同位置的数据筛选窗口,根据实时检测数据来识别波形的变化趋势从而得到峰值强度与位置,进而计算出对应的光信号峰值强度。实验结果显示,所研制的实时检测系统实现了对多波长光信号的实时检测以及峰值的识别,光信号检测强度范围为0~-60 dBm,识别速度较快,对于准周期或周期的多波长光信号的识别具有良好的识别效果。

关键词：光纤通信信号峰值检测系统光信号探测法布里-珀罗可调谐滤波器波分复用技术

The impact of tandem duplication on gene evolution in Solanaceae species

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Journal of Integrative Agriculture 2022年第4期21卷 1004-1014页

作者： HUANG Yi-le zhang Ling-kui zhang kang CHEN Shu-min HU Jian-bin CHENG Feng College of Horticulture Henan Agricultural UniversityZhengzhou 450002P.R.China Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesBeijing 100097P.R.China

Whole genome duplication(WGD) and tandem duplication(TD) are important modes of gene amplification and functional innovation, and they are common in plant genome evolution. We analyzed the genomes of three Solanaceae species(Solanum lycopersicum, Capsicum annuum, and Petunia inflata), which share a common distant ancestor with Vitis vinifera, Theobroma cacao, and Coffea canephora but have undergone an extra whole genome triplication(WGT) event. The analysis was used to investigate the phenomenon of tandem gene evolution with(S. lycopersicum) or without WGT(V. vinifera). Among the tandem gene arrays in these genomes, we found that V. vinifera, which has not experienced the WGT event, retained relatively more and larger tandem duplicated gene(TDG) clusters than the Solanaceae species that experienced the WGT event. Larger TDG clusters tend to be derived from older TD events, so this indicates that continuous TDGs(absolute dosage) accumulated during long-term evolution. In addition, WGD and TD show a significant bias in the functional categories of the genes retained. WGD tends to retain dose-sensitive genes related to biological processes, including DNA-binding and transcription factor activity, while TD tends to retain genes involved in stress resistance. WGD and TD also provide more possibilities for gene functional innovation through gene fusion and fission. The TDG cluster containing the tomato fusarium wilt resistance gene I3 contains 15 genes, and one of these genes, Solyc07g055560, has undergone a fusion event after the duplication events. These data provide evidence that helps explain the new functionalization of TDGs in adapting to environmental changes.

关键词： tandem duplication whole genome duplication Solanaceae species gene retention gene fusion

Genome-wide identification,evolutionary selection,and genetic variation of DNA methylation-related genes in Brassica rapa and Brassica oleracea

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Journal of Integrative Agriculture 2022年第6期21卷 1620-1632页

作者： AN Feng zhang kang zhang Ling-kui LI Xing CHEN Shu-min WANG Hua-sen CHENG Feng Collaborative Innovation Center for Efficient and Green Production of Agriculture in Zhejiang Mountainous Areas College of Horticulture ScienceZhejiang A&F UniversityHangzhou 311300P.R.China Institute of Vegetables and Flowers Chinese Academy of Agricul tural SciencesBeijing 100081P.R.China

DNA methylation plays an important role in plant growth and development,and in regulating the activity of transposable elements(TEs).Research on DNA methylation-related(DMR)genes has been reported in Arabidopsis,but little research on DMR genes has been reported in Brassica rapa and Brassica oleracea,the genomes of which exhibit significant differences in TE content.In this study,we identified 78 and 77 DMR genes in Brassica rapa and Brassica oleracea,respectively.Detailed analysis revealed that the numbers of DMR genes in different DMR pathways varied in B.rapa and B.oleracea.The evolutionary selection pressure of DMR genes in B.rapa and B.oleracea was compared,and the DMR genes showed differential evolution between these two species.The nucleotide diversity(π)and selective sweep(Tajima’s D)revealed footprints of selection in the B.rapa and B.oleracea populations.Transcriptome analysis showed that most DMR genes exhibited similar expression characteristics in B.rapa and B.oleracea.This study dissects the evolutionary differences and genetic variations of the DMR genes in B.rapa and B.oleracea,and will provide valuable resources for future research on the divergent evolution of DNA methylation between B.rapa and B.oleracea.

关键词： DNA methylation Brassica rapa Brassica oleracea evolutionary selection genetic variation gene expression

高超声速飞行器指定时间时变高增益反馈跟踪控制

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自动化学报 2024年第6期50卷 1151-1159页

作者：张康康周彬蔡光斌侯明哲哈尔滨工业大学控制理论与制导技术研究中心哈尔滨 150006 火箭军工程大学导弹工程学院西安 710025

研究了高超声速飞行器控制通道存在未知环境干扰时的指定时间跟踪控制问题.基于高超声速飞行器的输入输出线性化模型,借助参量Lyapunov方程的一些性质,设计一种光滑、有界的时变高增益控制律.相比于现有的高超声速飞行器有限/固定时间... 详细信息

研究了高超声速飞行器控制通道存在未知环境干扰时的指定时间跟踪控制问题.基于高超声速飞行器的输入输出线性化模型,借助参量Lyapunov方程的一些性质,设计一种光滑、有界的时变高增益控制律.相比于现有的高超声速飞行器有限/固定时间控制方法,该算法不会出现抖振现象,同时收敛时间不依赖于初始状态且可以事先设定.当高超声速飞行器存在未知的有界环境匹配干扰时,该控制器能使高度和速度在指定时间跟踪上参考信号.仿真结果验证了方法的有效性.

关键词：高超声速飞行器指定时间控制时变反馈高增益反馈非线性控制

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静电成形薄膜反射面天线的裁剪设计

工程力学 2024年第6期41卷 224-234页

作者：杜雪林张瑞翔张康夏杰湖南工学院智能制造与机械工程学院湖南衡阳421002 西安电子科技大学电子装备结构设计教育部重点实验室陕西西安710071

该文通过裁剪和拼接平面薄膜片来对静电成形薄膜反射面天线的表面进行设计制作。由于抛物面型薄膜反射面是一个不可展开表面,通常由许多平面薄膜片制作而成,将不可避免地降低反射面表面的精度。因此,需要详细地分析裁剪和拼接过程对反... 详细信息

该文通过裁剪和拼接平面薄膜片来对静电成形薄膜反射面天线的表面进行设计制作。由于抛物面型薄膜反射面是一个不可展开表面,通常由许多平面薄膜片制作而成,将不可避免地降低反射面表面的精度。因此,需要详细地分析裁剪和拼接过程对反射面表面精度的影响,从而获得设计需要的表面精度。该文基于旋转抛物面的无矩理论建立了工作状态的反射面模型,采用常应变三角形单元离散反射面,建立了反射面的展平和拼接有限元模型。将同口径反射面沿经线划分若干组不同数量子曲面,通过子曲面进行展平和拼接数值仿真分析,对薄膜反射面进行裁剪设计。最后,制作了0.55 m口径的薄膜反射器,并进行了摄影测量实验。验证了该方法的有效性,并讨论了制造误差的影响。

关键词：机械工程结构设计数值仿真静电成形薄膜反射面三角形单元无矩理论裁剪设计摄影测量实验

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欧洲大型郁金香花瓶的中国塔起源探究

中国陶瓷 2024年第4期60卷 99-105页

作者：张康李雅谦淮阴师范学院淮安223000

欧洲17世纪后期到18世纪的油画、陶瓷工艺品和日常生活器皿中出现了大量中华文化元素。这是欧洲人在阅读有关中国的文献或图像资料和看到具有中国特色的实物之后选择性地撷取所产生的新变化。采用文献法、图像学和多元决定论等研究方法... 详细信息

欧洲17世纪后期到18世纪的油画、陶瓷工艺品和日常生活器皿中出现了大量中华文化元素。这是欧洲人在阅读有关中国的文献或图像资料和看到具有中国特色的实物之后选择性地撷取所产生的新变化。采用文献法、图像学和多元决定论等研究方法,从图像传播与接受角度切入,认为欧洲郁金香花瓶(tulip vases,塔形花瓶)是荷兰陶瓷设计师对约翰·尼霍夫《荷兰东印度公司使节团访华纪实》里中国塔图像的仿制和挪用,是“中国想象”的产物。指出荷兰国立博物馆2000年出版的《黄金时代的辉煌:荷兰17世纪绘画、雕塑和装饰艺术》将威廉三世花瓶烧制年代界定为约1690–1700年是错误的。期望对中华文化的多元价值和全球意义,尤其是17世纪至18世纪欧洲美术吸纳中华文化元素这一研究有补苴之功。

关键词：约翰·尼霍夫中国塔郁金香花瓶塔瓶