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Applied principle of minimum potential energy in analyzing buckle phenomenon of cold rolled strip

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Computer Aided Drafting,Design and Manufacturing 2016年第3期26卷 33-38页

作者： yang guanghui Zhang Jie Yan Qintai School of Mechanical Engineering University of Science and Technology Beijing

When solving buckling type based on minimum potential energy, it is first to make hypothesis for strip buckling type. Under the simple strain condition, buckling type and strain distribution have a certain similarity, so the hypothesis is reasonable comparatively. However, under the complicated strain condition, it is difficult to give more reasonable buckling type. Moreover, the existing algorithms usually ignore the effect which the transverse stress and the shear stress have on the buckling type. After assuming strip was only affected by shear stress for the edge wave and affected by both transverse stress and the shear stress for the center wave in the paper, the buckling form of strip under simple strain situation was calculated. It was seen from the calculating result that wave height and half wavelength were smaller than those of the existing algorithms, and the wave height and half wavelength of edge wave were all bigger than those of center wave in the same stress distribution. Secondly, a more reasonable hypothesis method of buckling type for the complicated stress distribution was put forward. After analyzing, the result showed that it was more reasonable by using the optimizing algorithm.

关键词： cold rolled strip buckle minimum potential energy

Transverse distribution law of airflow excitation force for SI-FLAT contactless shapometer

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Computer Aided Drafting,Design and Manufacturing 2016年第4期26卷 41-47页

作者： yang guanghui Zhang Jie Li Hongbo School of Mechanical Engineering University of Science and Technology Beijing

Aiming at the shape problems in production, the finite element model was built with the Fluent software to analyze the transverse distribution laws of airflow excitation force under different factors which affected the detection precision. For analyzing the shape errors caused by the non-uniform transverse distribution of airflow excitation force, the finite element model of strip is built with the ANSYS12.0 software. It is found in the study results that the airflow excitation forces display the same distribution laws under different rolling conditions, i.e. have an obvious attenuation at the edge of strip~ which causes large shape measurement errors. For reducing shape errors, the compensation project is put forward, and it gives a good foundation for improving the detection precision.

关键词： contactless measurement flatness amplitude SI-FLAT shapometer airflow excitation force

High-Order Disturbance Observer-Based Attitude Control with Prescribed Performance for Hypersonic Vehicle

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High-Order Disturbance Observer-Based Attitude Control with ...

Introduction and analysis of shaping design of parts and some typical shaping method

第40届中国控制会议

作者： guanghui yang Xinming Wang Beijing Aerospace Automatic Control Institute School of Automation Southeast University Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Eduaction

This paper presents a high-order disturbance observer-based attitude tracking controller design with prescribed performance for hypersonic vehicle. The lumped disturbances caused by parameters perturbations, external disturbances and unmodelled dynamics are estimated accurately by utilizing high-order disturbance observers. Based on the disturbances estimation,a composite attitude tracking controller with guaranteeing prescribed transient and steady performance is proposed and the stability analysis of the closed-loop system is rigorously analyzed using the Lyapunov technique. The proposed controller not only ensures the tracking errors are within the desired performance envelope but also considering the disturbance rejection. Finally,the effectiveness of the proposed method is verified by simulations.

关键词： Hypersonic Vehicle Disturbance Observer Prescribed Performance Control Dynamics Surface Control

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Computer Aided Drafting,Design and Manufacturing 2016年第3期26卷 53-60页

作者： yang guanghui Chen Hua Liu Ziping Li Lixin School of Mechanical Engineering University of Science and Technology Beijing School of Mechanical and Electronic Engineering Beijing Union University

In order to improve the shaping design ability of students in mechanical drawing, it is necessary to introduce and analyze the shaping design of parts and some typical shaping method. Firstly, shaping designs of different structures of some parts such as installation part, connection part and so on are introduced, and then the shaping design procedure of the base of reducer is analyzed. Secondly, some typical shaping design methods such as shaping design based on the deformation of the basic body, profile design shaping design, complementary shaping design, equal volume shaping design, variation shaping design and combinatorial shaping design are introduced and analyzed. Finally, the design model of various pipe joints used in the exhibition hall is given as a design question. It will be helpful to improve the spatial imagination and shaping ability of students.

关键词： shaping method mechanical drawing spatial imagination

基于转子磁链优化的五相感应电机电子变极策略

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电工技术学报 2022年第14期37卷 3587-3597,3631页

作者：贾慧利杨家强杨光辉浙江大学电气工程学院杭州310027 芜湖职业技术学院芜湖241006

针对五相感应电机(FIM)指数响应转矩跟踪电子变极运行不平稳问题,分析得出转子磁链饱和是导致该问题的主要原因之一,计及磁链饱和提出一种转子磁链优化(RFO)电子变极控制策略。分析了FIM电子变极过程中两个控制平面转子磁链叠加是导致... 详细信息

针对五相感应电机(FIM)指数响应转矩跟踪电子变极运行不平稳问题,分析得出转子磁链饱和是导致该问题的主要原因之一,计及磁链饱和提出一种转子磁链优化(RFO)电子变极控制策略。分析了FIM电子变极过程中两个控制平面转子磁链叠加是导致磁链饱和的原因,设计了转子磁链控制函数,并采用磁链幅值和电磁转矩约束函数使转子磁链逼近临界值,优化了转子磁链控制。基于FIM的Speedgoat半实物实验平台,对所提RFO方法进行了实验验证,对采用和未采用RFO的指数响应转矩跟踪电子变极控制策略进行对比实验研究。实验结果表明,所提策略使转速波动减小了50%,转矩波动减小了67%,有效改善了电子变极过程中电机运行平稳性。

关键词：五相感应电机(FIM) 电子变极磁链饱和约束函数转子磁链优化(RFO)

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声信号特征融合的变压器故障判断方法

北京理工大学学报 2022年第3期42卷 233-241页

作者：杨光辉杨光粲黎宏锐北京科技大学机械工程学院北京100083

针对变压器故障种类繁多、故障样本不足的问题,提出了一种声信号特征融合的变压器故障判断方法.在正常变压器中提取大量正常声信号,从中找到符合变压器特性的特征.在时域、频域等不同空间域中对采集的变压器正常声信号进行特征提取,由... 详细信息

针对变压器故障种类繁多、故障样本不足的问题,提出了一种声信号特征融合的变压器故障判断方法.在正常变压器中提取大量正常声信号,从中找到符合变压器特性的特征.在时域、频域等不同空间域中对采集的变压器正常声信号进行特征提取,由最大相关-最小冗余算法找到最符合变压器声信号的特征集,并对特征集利用加权熵主成分法得到融合指标.对某变电站220 kV和110 kV变压器正常信号与故障仿真信号在噪声干扰的情况下对融合指标进行了比较,结果表明:该方法获取的融合指标在正常与仿真故障情况下区分明显,具有良好的识别效果,验证了该方法的可行性.

关键词：变压器声信号特征融合最大相关-最小冗余故障判断

5-7 Geometrical Research on the Flow Rate of the Gravity-driven Dense Granular Flow Target

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IMP & HIRFL Annual Report 2015年第1期 229-230页

作者： Wan Jiangfeng Zhang Sheng Tian Yuan Lin Ping yang guanghui yang Lei 不详

Following previous designs such as plate targets, rod targets, rotating targets and liquid metal targets, the gravity-driven dense granular-flow target (DGT), which combines the advantages of solid and liquid metal targets,becomes a new attractive choice[1]. The geometry of DGT consists of a cylindrical hopper and an internal coaxial cylindrical beam pipe as shown in Fig. 1. Using discrete element method (DEM) simulations on GPUs, we research into the relations of the flow rate with the geometrical parameters.

关键词： Granular Flow Target

Criteria for Beverloo’s Scaling Law

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IMP & HIRFL Annual Report 2018年第1期 206-208页

作者： Lin Ping Zhang Sheng yang guanghui Wan Jiangfeng Tian Yuan yang Lei 不详

Beverloo’s scaling law is capable to describe the flow rate of grains discharging from *** this paper it shows the Beverloo’s scaling law is valid for varying material *** the flow rates from a hopper with different hopper and orifice size(D,D0)are studied by running large-scale *** hopper size is fixed,numerical results show that Beverloo’s law is valid even if the orifice diameter is very large and then the criteria for this law are discussed.

关键词： parameters. scaling flow

Paternally imprinted LATE-FLOWERING2 transcription factor contributes to paternal-excess interploidy hybridization barriers in wheat∞

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Journal of Integrative Plant Biology 2023年第12期65卷 2587-2603页

作者： guanghui yang Man Feng Kuohai Yu Guangxian Cui Yan Zhou Lv Sun Lulu Gao Yumei Zhang Huiru Peng Yingyin Yao Zhaorong Hu Vincenzo Rossi Ive De Smet Zhongfu Ni Qixin Sun Mingming Xin State Key Laboratory for Agrobiotechnology Key Laboratory of Crop Heterosis Utilization(MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China Qingdao Agricultural University Qingdao 266109China Council for Agricultural Research and Economics Research Centre for Cereal and Industrial CropsBergamo 24126Italy Department of Plant Biotechnology and Bioinformatics Ghent UniversityGhent B‐9052Belgium VIB Center for Plant Systems Biology Ghent B‐9052Belgium

Interploidy hybridization between hexaploid and tetraploid genotypes occurred repeatedly during genomic introgression events throughout wheat evolution,and is commonly employed in wheat breeding *** wheat usually serves as maternal parent because the reciprocal cross generates progeny with severe defects and poor seed germination,but the underlying mechanism is poorly ***,we performed detailed analysis of phenotypic variation in endosperm between two interploidy reciprocal crosses arising from tetraploid(Triticum durum,AABB)and hexaploid wheat(Triticum aestivum,AABBDD).In the paternal‐versus the maternal‐excess cross,the timing of endosperm cellularization was delayed and starch granule accumulation in the endosperm was repressed,causing reduced germination *** expression profiles of genes involved in nutrient metabolism differed strongly between these endosperm ***,expression patterns of parental alleles were dramatically disturbed in interploidy versus intraploidy crosses,leading to increased number of imprinted *** endosperm‐specific TaLFL2 showed a paternally imprinted expression pattern in interploidy crosses partially due to allele‐specific DNA *** TaLFL2 binds to and represses a nutrient accumulation regulator TaNAC019,leading to reduced storage protein and starch accumulation during endosperm development in paternal‐excess cross,as confirmed by interploidy crosses between tetraploid wild‐type and clustered regularly interspaced palindromic repeats(CRISPR)–CRISPR‐associated protein 9 generated hexaploid *** findings reveal a contribution of genomic imprinting to paternal‐excess interploidy hybridization barriers during wheat evolution history and explains why experienced breeders preferentially exploit maternal‐excess interploidy crosses in wheat breeding programs.

关键词： imprinting interploidy cross wheat