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Forming process chain for manufacturing complex conical-section profiled rings:On a co-design method

Chinese Journal of Aeronautics 2024年第6期37卷 485-503页

作者： lei liang Chaojiang ZOU lianggang GUO State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Guizhou Aviation Technology Development Co.Ltd Guiyang 550081China

The final quality of complex conical-section rings depends on co-design of multiple processes in forming process chain.In this study,for a complex aeroengine casing ring with a large slope and a flange on its end,a co-design method of the forming process chain is put forward towards the objective of precision forming,which not only proposes a standard process route composed of multiple processes of upsetting,punching,rectangular ring rolling,loose tooling forging and profiled ring rolling,but also presents co-design methods of dies and blanks for all the processes.For profiled ring rolling,a design method of preformed blank that makes the blank and the target conical-section ring have the same axial volume distribution is proposed.By the method,the axial metal redistribution during the process can be alleviated greatly thus improving the forming stability and precision of the ring.Based on the geometric features of designed preformed blank,design methods of blanks and dies for loose tolling forging,rectangular ring rolling,punching and upsetting are proposed sequentially.In view of the key roles of loose tooling forging(manufacturing the preformed blank)and profiled ring rolling on the final quality of the conical ring parts,inherited FE simulations for these two processes are performed to verify the proposed design methods and determine appropriate design parameter.It is demonstrated that the proposed design method has significant advantages in improving forming precision.Besides,a suggestive value 1.5 of the rolling ratio for profiled ring rolling(a key design parameter)is given based on comprehensive consideration of multiple indicators such as ring roundness,deformation uniformity and forming load.The corresponding industrial experiments performed illustrate that a high forming precision of the conical-section aeroengine casing ring is achieved.

关键词： Complex conical-section ring Co-design of forming process chain Profiled ringrolling Preformed blank Loose tooling forging

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SPATULA as a Versatile Tool in Plant:The Progress and Perspectives of SPATULA(SPT)Transcriptional Factor

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 517-531页

作者： lei liang Xiangyang Hu Shanghai Key Laboratory of Bio-Energy Crops Research Center for Natural ProductsPlant Science CenterSchool of Life SciencesShanghai UniversityShanghai200444China

With the rapid development of modern molecular biology and bioinformatics,many studies have proved that transcription factors play an important role in regulating the growth and development of plants.SPATULA(SPT)belongs to the bHLH transcription family and participates in many processes of regulating plant growth and development.This review systemically summarizes the multiple roles of SPT in plant growth,development,and stress response,including seed germination,ﬂowering,leaf size,carpel development,and root elongation,which is helpful for us to better understand the functions of SPT.

关键词： SPT bHLH plant growth plant development Arabidopsis thaliana

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True-temperature inversion algorithm for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization

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Nanotechnology and Precision Engineering 2024年第1期7卷 55-62页

作者： Mei liang Zhuo Sun Jiasong Liu Yongsheng Wang lei liang Long Zhang School of Electromechanical and Automotive Engineering Yantai UniversityYantai 264005China liangshan Mining Co. Ltd.Huili 615141China

Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difﬁcult inversion problems with unknown emissivity.Fractional-order calculus has the inherent advantage of easily jumping out of local extreme values;here,it is introduced into the particle-swarm algorithm to invert the true temperature.An improved adaptive-adjustment mechanism is applied to automatically adjust the current velocity order of the particles and update their velocity and position values,increasing the accuracy of the true temperature values.The results of simulations using the proposed algorithm were compared with three algorithms using typical emissivity models:the internal penalty function algorithm,the optimization function(fmincon)algorithm,and the conventional particle-swarm optimization algorithm.The results show that the proposed algorithm has good accuracy for true-temperature inversion.Actual experimental results from a rocket-motor plume were used to demonstrate that the true-temperature inversion results of this algorithm are in good agreement with the theoretical true-temperature values.

关键词： Fractional-order particle swarm True-temperature inversion algorithm Multi-wavelength pyrometer

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Expansion and improvement of ChinaMu by MuT-seq and chromosome-level assembly of the Mu-starter genome

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Journal of Integrative Plant Biology 2024年第4期66卷 645-659页

作者： lei liang Yuancong Wang Yanbin Han Yicong Chen Mengfei Li Yibo Wu Zeyang Ma Han Zhao Rentao Song State Key Laboratory of Maize Bio-breeding Frontiers Science Center for Molecular Design BreedingJoint International Research Laboratory of Crop Molecular BreedingNational Maize Improvement CenterCollege of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100091China Institute of Crop Germplasm and Biotechnology Jiangsu Provincial Key Laboratory of AgrobiologyJiangsu Academy of Agricultural SciencesNanjing 210014China Sanya Institute of China Agricultural University Sanya 572025China Hainan Yazhou Bay Seed Laboratory Sanya 572025China

ChinaMu is the largest sequence-indexed Mutator(Mu)transposon insertional library in maize(Zea mays).In this study,we made significant improvements to the size and quality of the ChinaMu library.We developed a new Mu-tag isolation method Mu-Tn5-seq(MuT-seq).Compared to the previous method used by ChinaMu,MuT-seq recovered 1/3 more germinal insertions,while requiring only about 1/14 of the sequencing volume and 1/5 of the experimental time.Using MuT-seq,we identified 113,879 germinal insertions from 3,168 Mu-active F1 families.We also assembled a high-quality genome for the Mu-active line Mu-starter,which harbors the initial active MuDR element and was used as the pollen donor for the mutation population.Using the Mu-starter genome,we recovered 33,662(15.6%)additional germinal insertions in 3,244(7.4%)genes in the Mu-starter line.The Mu-starter genome also improved the assignment of 117,689(54.5%)germinal insertions.The newly upgraded ChinaMu dataset currently contains 215,889 high-quality germinal insertions.These insertions cover 32,224 pan-genes in the Mu-starter and B73Ref5 genomes,including 23,006(80.4%)core genes shared by the two genomes.As a test model,we investigated Mu insertions in the pentatricopeptide repeat(PPR)superfamily,discovering insertions for 92%(449/487)of PPR genes in ChinaMu,demonstrating the usefulness of ChinaMu as a functional genomics resource for maize.

关键词： ChinaMu Mutator MuT-seq PPR gene Zea mays

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PDDD-PreTrain:A Series of Commonly Used Pre-Trained Models Support Image-Based Plant Disease Diagnosis

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Plant Phenomics 2023年第2期5卷 313-332页

作者： Xinyu Dong Qi Wang Qianding Huang Qinglong Ge Kejun Zhao Xingcai Wu Xue Wu liang lei Gefei Hao State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang 550025China The School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou 510006China National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China

Plant diseases threaten global food security by reducing crop yield;thus,diagnosing plant diseases is critical to agricultural production.Artificial intelligence technologies gradually replace traditional plant disease diagnosis methods due to their time-consuming,costly,inefficient,and subjective disadvantages.As a mainstream AI method,deep learning has substantially improved plant disease detection and diagnosis for precision agriculture.In the meantime,most of the existing plant disease diagnosis methods usually adopt a pre-trained deep learning model to support diagnosing diseased leaves.However,the commonly used pre-trained models are from the computer vision dataset,not the botany dataset,which barely provides the pre-trained models sufficient domain knowledge about plant disease.Furthermore,this pre-trained way makes the final diagnosis model more difficult to distinguish between different plant diseases and lowers the diagnostic precision.To address this issue,we propose a series of commonly used pre-trained models based on plant disease images to promote the performance of disease diagnosis.In addition,we have experimented with the plant disease pre-trained model on plant disease diagnosis tasks such as plant disease identification,plant disease detection,plant disease segmentation,and other subtasks.The extended experiments prove that the plant disease pre-trained model can achieve higher accuracy than the existing pre-trained model with less training time,thereby supporting the better diagnosis of plant diseases.In addition,our pre-trained models will be open-sourced at https://***/and Zenodo platform https://***/10.5281/zenodo.7856293.

关键词： diagnosis Plant thereby

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基因编辑技术在不同国家生物安全法规下的应用实践与效果分析

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分子植物育种 2024年第13期22卷 4304-4309页

作者：梁磊河北环境工程学院秦皇岛066102

本研究对不同国家生物安全法规下基因编辑技术的应用及其效果进行了深入分析和比较,旨在探索如何在创新与安全、伦理与效率之间找到平衡;通过概述基因编辑技术,尤其是CRISPR-Cas9技术的基本原理和重要性,突显了该技术的前沿地位和潜力;... 详细信息

本研究对不同国家生物安全法规下基因编辑技术的应用及其效果进行了深入分析和比较,旨在探索如何在创新与安全、伦理与效率之间找到平衡;通过概述基因编辑技术,尤其是CRISPR-Cas9技术的基本原理和重要性,突显了该技术的前沿地位和潜力;进一步讨论了国际生物安全法规的背景和主要内容,以及它们如何影响科研和技术应用,特别是在美国、中国和欧洲联盟等地区的具体实践和效果;还考察了这些法规对研究机构、企业和国际合作的影响,以及在农业和医学领域中基因编辑技术应用的成效与挑战,并探讨了相关的潜在风险和伦理问题。本研究基于对不同国家生物安全法规的分析提出了未来研究方向和政策建议,目的是促进基因编辑技术的健康发展和形成有效的全球生物安全管理框架。

关键词：基因编辑技术生物安全法规国际合作技术应用实践伦理与风险管理

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MADM gives new insights into gliomagenesis

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分子细胞生物学报:英文版 2011年第5期3卷 273-275页

作者： liang lei Peter Canoll Department of Pathology and Cell Biology Columbia UniversityNew YorkNY 10032USA

In their recent paper,Liu et al.(2011)make use of an elegant genetic mouse model to study the formation of malignant brain tumors.Their findings add strong support to the growing body of evidence from several labs showing that some gliomas arise from oligodendrocyte precursor cells(OPCs).They also provide new insights,and raise new questions,regarding where,when,and how malignant gliomas form.

关键词： glioma al. malignant

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面向DAS系统的震源信号初至波到达时间拾取方法

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激光与光电子学进展 2024年第9期61卷 272-278页

作者：黄亮梁磊江轲杜尚明武汉理工大学光纤传感技术与网络国家工程研究中心湖北武汉430070 武汉理工大学信息工程学院湖北武汉430070

在基于相敏光时域反射计(Φ-OTDR)的光纤分布式声传感(DAS)系统定位震源二维空间位置方法中,由于干扰和噪声的影响,存在震源初至波到达光缆不同位置时间信息获取不准确的问题,带来较大的定位误差。针对DAS系统,提出了一种基于双边滤波... 详细信息

在基于相敏光时域反射计(Φ-OTDR)的光纤分布式声传感(DAS)系统定位震源二维空间位置方法中,由于干扰和噪声的影响,存在震源初至波到达光缆不同位置时间信息获取不准确的问题,带来较大的定位误差。针对DAS系统,提出了一种基于双边滤波边缘检测的震源初至波到达时间拾取方法。首先,将DAS系统采集的震源时空二维信号转换成灰度图,用双边滤波方法进行降噪,然后,应用基于Canny算子的边缘检测方法提取灰度图像中的边缘特征,来获得震源初至波到达时间。这种方法能够同时考虑时空二维数据的时间和空间整体特征,提高低信噪比信号初至波到达时间的拾取精度。现场实验表明,该方法对于受干扰和系统噪声影响的低信噪比信号,拾取的到达时间平均误差不超过3 ms,拾取精度比传统方法高,算法平均耗时仅需0.1 s,拾取时间短。

关键词：分布式声传感震源边缘检测双边滤波到达时间拾取

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Comparision of Methods for Polarimetric SAR Tomography with Small Number of Baselines in Forested Areas

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Chinese Journal of Electronics 2019年第5期28卷 1073-1079页

作者： liang lei ZHOU Chenghu LI Xinwu GAO Xizhang WU Wenjin State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Digital Earth Sciences Institute of Remote Sensing and Digital Earth (RADI) Chinese Academy of Sciences

Synthetic aperture radar Tomography(TomoSAR) provides scene reflectivity estimation of vegetation along elevation coordinates. However, the more multi-baselines acquisition, the longer the time span of acquisition, which will result in serious temporal decorrelation in forested area. In this way, we expect to use as smaller number of baselines as possible to obtain high estimation accuracy in elevation direction. We thus investigate the performance of Polarimetric SAR tomography(Pol-TomoSAR) with small number of baselines in forested areas. The results show that compressive sensingbased Pol-TomoSAR has higher estimation accuracy in elevation direction than conventional Pol-TomoSAR with small number of baselines.

关键词： Synthetic aperture radar(SAR) Polarimetric SAR SAR tomography Compressive sensing

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钢铁园区储位分配的多目标模型及算法研究

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机械设计与制造 2024年第6期400卷 70-74,80页

作者：梁晓磊郑丽兰梅磊武汉科技大学汽车与交通工程学院湖北武汉430065 江汉大学智能制造学院湖北武汉430056

针对钢铁物流园堆场内由于区储位分配不合理导致的车辆长时间排队等货、堆区作业堵塞等问题,提出以优化出入场时间和均衡园区堆场总作业量的多目标优化模型。模型中综合考虑需求量和受订频次因素对货位分配位置的影响,构建了以缩短运输... 详细信息

针对钢铁物流园堆场内由于区储位分配不合理导致的车辆长时间排队等货、堆区作业堵塞等问题,提出以优化出入场时间和均衡园区堆场总作业量的多目标优化模型。模型中综合考虑需求量和受订频次因素对货位分配位置的影响,构建了以缩短运输距离的单区货位布局优化子目标,同时为避免作业量过度集中,减少装卸作业堵塞,针对全堆场构建了基于出入库频率划分的货物堆场内作业均衡子目标。为高效求解该多目标模型,针对NSGA-II算法存在的Pareto前沿分布不均匀及局部拥挤区域的分布性优化不佳,提出了自适应分层保留和区间种群扩张的改进策略,构建了改进多目标优化算法(Hierarchical Retention and Interval Population Expansion NSGA-II,HRIPE-NSGA-II)。基于实际案例进行了模型和算法验证试验,结果表明该模型在HRIPE-NSGA-II求解下能够获得比对比算法更优的解方案,缩短车辆在园区内作业停留时间,平衡各区作业量,提高堆场运作效率。

关键词：钢铁物流园储位分配多目标优化改进NSGA-II

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