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A Hot Cracking Initiation Criterion Based on Solidification Liquid Film Characteristic and Microstructure

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1776-1790页

作者： Ming Su Wentao Zheng chunyu yue Bowen Zheng Xiaojiao Zuo Mengyuan He Xiaoguang Yuan School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China School of Materials Science and Engineering Northeastern UniversityShenyang110870China

Herein,a hot cracking initiation criterion based on the characteristics of solidification liquid film and the microstructure was proposed,which integrated both the mechanical and non-mechanical factors during *** criterion also took the effect of the shrinkage volume of the solid-liquid two-phase in the mushy zone,the flow behavior of the liquid film and the microstructure on the feeding behavior into ***,the effect factors of hot cracking initiation such as alloy composition,microstructure,mold design and process condition were included in this criterion,and it could quantitatively calculate whether hot cracks occurred under a certain state or not during *** criterion was utilized to predict whether hot cracks occurred in Al-4.0 wt%Cu alloy in different initial solidification states or not,which was consistent with the experimental results and verified its *** to the criterion expression,Vfeeding*was related with five effect factors includingη,ΔP*,l*,r*and n,in which r*and n were in positive correlation with Vfeeding*whileη,ΔP*and l*were in negative correlation with that,which provided a good instructive significance for mold design,process optimization and composition and microstructure regulation of alloys and simultaneously further enriched the mechanism and influencing factors of hot cracking ***,a multiscale simulation method for calculating the characteristic parameters of hot tearing behavior during solidification was also provided in this study.

关键词： Hot cracking criterion Liquid film characteristic Microstructure Aluminum alloy Multiscale simulation

Experimental and numerical study of combustion characteristics of ammonia-hydrogen-air swirling flame with/without secondary air injection

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Chinese Journal of Aeronautics 2024年第4期37卷 243-255页

作者： chunyu LIU Chenhu GAO yue HUANG Hua JIN Dan ZHAO Wenjiang XU Yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361005China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand

Ammonia (NH_(3)) is currently considered to be a potential carbon-free alternative fuel,and its large-scale use as such would certainly decrease greenhouse gas emissions and meet increasingly stringent emission *** the low flame propagation speed and high NO production of NH_(3) hinder its direct application as a renewable fuel,co-combustion of NH_(3)–H_(2)is an effective way to overcome these *** this study,the combustion characteristics of NH_(3)–H_(2)swirling flames under different equivalence ratios and H_2blending ratios conditions are both numerically and experimentally ***,the One-Dimensional (1D) laminar flame computation presents a comparison base and the Three-Dimensional (3D) numerical simulation yields detailed flame property ***,the high-speed camera takes instantaneous swirl flame images and the gas analyzer measures the NO emission at the exit plane of the flame *** and quantitative analysis is performed on the flame structure and NO emission for a series of NH_(3)–H_(2)swirl *** variation trends of the NO emission calculated using different techniques agree very *** quantitative results show that the NO emissions are much higher at lean equivalence ratios than those at rich equivalence ratios,and such difference is closely related to the combustion flame ***,it is shown that the utilization of secondary air injection can achieve a significant reduction in NO emissions at the exit of the combustion chamber at equivalence ratios less than or equal to 0.9.

关键词： Ammonia combustion Swirling flow NO emission characteristics Secondary combustion Chemical reaction mechanism

基于Kriging模型的自适应多阶段并行代理优化算法

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计算机集成制造系统 2021年第11期27卷 3227-3235页

作者：乐春宇马义中南京理工大学经济管理学院江苏南京210094

为了充分利用计算资源,减少迭代次数,提出一种可以批量加点的代理优化算法。该算法分别采用期望改进准则和WB2(Watson and Barnes)准则探索存在的最优解并开发已存在最优解的区域,利用可行性概率和多目标优化框架刻画约束边界。在探索... 详细信息

为了充分利用计算资源,减少迭代次数,提出一种可以批量加点的代理优化算法。该算法分别采用期望改进准则和WB2(Watson and Barnes)准则探索存在的最优解并开发已存在最优解的区域,利用可行性概率和多目标优化框架刻画约束边界。在探索和开发阶段,设计了两种对应的多点填充算法,并根据新样本点和已知样本点的距离关系,设计了两个阶段的自适应切换策略。通过3个不同类型算例和一个工程实例验证算法性能,结果表明,该算法收敛更快,其结果具有较好的精确性和稳健性。

关键词： Kriging模型代理优化加点准则可行性概率多点填充

Design of line-of-sight stabilized control system using inertial and optical-mechanical combined method

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Design of line-of-sight stabilized control system using iner...

Particle Swarm Optimized Adaptive Dynamic Surface Control for PMSM Servo System

第36届中国控制会议

作者： Huang Gang Lin Zhe Ziyin Chen Jianbing Kang chunyu yue Beijing Institute of Space Mechanics ＆ Electricity

ISBN: (纸本)9781538629185

To improve the stabihty accuracy of stable platform of unmanned aerial vehicle（UAV）,a line-of-sight stabilized control system is developed by using an inertial and optical-mechanical（fast steering mirror） combined method in a closed loop with visual *** system is based on Peripheral Component Interconnect（PCI）,included an image-deviation-obtained system and a combined controller using a PQ *** method changes the series-wound structure to the shunt-wound structure of dual-input/single-output（DISO）,and decouples the actuator range and frequency of inertial stabilization and fast steering mirror *** results show the stability accuracy improves from 20μrad of inertial method to 5μrad of inertial and optical-mechanical combined method,and prove the effectiveness of the combined line-of-sight stabilization control system.

关键词： inertial stability optical-mechanical stability combined line-of-sight stabilization control system stability accuracy

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Particle Swarm Optimized Adaptive Dynamic Surface Control fo...

第36届中国控制会议

作者： Ziyin Chen Zhe Lin Gang Huang Heming Jia chunyu yue Beijing Institute of Space Mechanics & Electricity College of Mechanical and Electrical Engineering Northeast Forestry University

ISBN: (纸本)9781538629185

To solve the control problem of permanent magnet synchronous motor（PMSM） for servo system in the present of parameter uncertainties,we design an adaptive backstepping controller with dynamic surface method,the derivatives of virtual control variables can be approximated through a first-order filter,which can avoid the needs for repeated computing the derivatives of virtual control in backstepping design,meanwhile some nonlinear coupled terms are reserved instead of using directly nonlinear cancellation in feedback linearization,which can further simplify the resulted *** adaptation laws are designed through Lyapunov stability analysis with guaranteed uniformly ultimately bounded convergence for close-loop *** swarm optimization（PSO） algorithm is adopted to determine the optimal parameters for the controller by minimizing the objective ***,the simulation results are presented to prove the effectiveness and robustness of the proposed controller.

关键词： permanent magnet synchronous motor(PMSM) backstepping dynamic surface control(DSC) adaptive control particle swarm optimization(PSO)

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一种星载激光测高仪光斑内定位方法

武汉大学学报（信息科学版） 2019年第4期44卷 586-592页

作者：岳春宇孙世君何红艳北京空间机电研究所北京100094 先进光学遥感技术北京市重点实验室北京100094 清华大学精密仪器与机械学系北京100084

提出一种利用铅垂线轨迹法及高程结构信息约束的星载激光测高仪光斑内定位方法。在星载激光测高仪辅助立体摄影测量体制下,以激光回波中包含的高精度高程结构信息作为约束条件,在足印光斑内,配合立体图像匹配生成的数字高程模型,选取定... 详细信息

提出一种利用铅垂线轨迹法及高程结构信息约束的星载激光测高仪光斑内定位方法。在星载激光测高仪辅助立体摄影测量体制下,以激光回波中包含的高精度高程结构信息作为约束条件,在足印光斑内,配合立体图像匹配生成的数字高程模型,选取定位候选点,并通过铅垂线轨迹法优化定位候选点高程值,消除立体图像定位误差引起的高程误差,获取符合高程结构约束的一系列位置的三维坐标。试验结果表明,该方法能够实现大光斑星载激光测高仪足印内的定位,高程定位精度为0.16 m,平面定位精度与立体图像一致。

关键词：星载激光测高仪全波形数据铅垂线轨迹法几何定位高程结构

天基大气环境观测激光雷达技术和应用发展研究

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红外与激光工程 2018年第3期47卷 8-21页

作者：郑永超王玉诏岳春宇北京空间机电研究所北京100094 北京空间技术研究院激光信息感知核心专业实验室北京100094

根据大气观测目标,从云-气溶胶、风场和大气分子三个主要方向对天基激光雷达在大气环境观测领域的应用、配置和相关技术发展进行了分析,研究了天基大气环境探测激光雷达的探测机制、技术体制、系统配置、应用现状、适用范围、约束条件等... 详细信息

根据大气观测目标,从云-气溶胶、风场和大气分子三个主要方向对天基激光雷达在大气环境观测领域的应用、配置和相关技术发展进行了分析,研究了天基大气环境探测激光雷达的探测机制、技术体制、系统配置、应用现状、适用范围、约束条件等,提出天基大气环境观测激光雷达载荷研制应根据任务应用需求、科学和工程目标、各技术体制特点和器件及处理技术特点合理制定指标体系,充分发挥激光技术长项,与其他载荷手段优化配置,技术研究方面应扬长补短短,并在此基础上展望了天基大气环境观测技术和应用的发展趋势、研究热点及其应用拓展。

关键词：激光雷达大气海洋环境

Dt1 inhibits SWEET-mediated sucrose transport to regulate photoperiod-dependent seed weight in soybean

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Molecular Plant 2024年第3期17卷 496-508页

作者： Xiaoming Li Zhonghui Chen Haiyang Li Lin yue Cuirong Tan Hongjie Liu Yilong Hu Yuhua Yang Xiani Yao Lingping Kong Xiang Huangi Bin Yu chunyu Zhang yuefeng Guan Baohui Liu Fanjiang Kong Xingliang Hou Guangdong Provincial Key Laboratory of Applied Botany&State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academyof SciencesGuangzhou510650China Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life SciencesGuangzhou UniversityGuangzhou 510006China University of Chinese Academy of Sciences Beijing 100049China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length *** weight is one of the key traits determining the soybean yield;how-ever,the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly *** this study,we identify SwW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1,an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit,as the causal gene of the SW19 *** showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in *** analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo,thus modulating seed weight under long ***,Dt1 does not function in seed development under short days due to its very low ***,we discovered a novel natural allelic variant of Dt1(H4 haplotype)that decouples its pleiotropic effects on seed size and growth habit;i.e.,this variant remains functional in seed development but fails to regulate the stem growth habit of ***,our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes,offering an ideal genetic component for improving soybean's yield by manipulating its seed weightandgrowth habit.

关键词： soybean seed weight photoperiod dt1 sucrose transport

以交叉累积剩余熵为准则的星载激光测高仪大光斑波形数据与地形匹配法

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测绘学报 2017年第3期46卷 346-352页

作者：岳春宇邢坤鲍云飞周楠何红艳北京空间机电研究所北京100094

提出了一种基于交叉累积剩余熵的星载激光测高仪大光斑波形数据与地形匹配方法。根据星载激光测高仪大光斑回波波形信号包含地形结构信息的特性,将激光回波波形数据和数字表面模型(DSM)投影到统计特征空间,建立数据的统计特征向量,消除... 详细信息

提出了一种基于交叉累积剩余熵的星载激光测高仪大光斑波形数据与地形匹配方法。根据星载激光测高仪大光斑回波波形信号包含地形结构信息的特性,将激光回波波形数据和数字表面模型(DSM)投影到统计特征空间,建立数据的统计特征向量,消除数据间维度差异,以交叉累积剩余熵为相似性测度匹配波形数据与地形的统计特征。试验结果表明,本方法能够较好地实现激光回波波形数据与地形的匹配,匹配精度达到一个像素以内。

关键词：星载激光测高仪大光斑回波信号地形匹配统计特征交叉累积剩余熵