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Journal of Systems Science & Complexity 2024年第4期37卷 1507-1525页

作者： ZHANG Zhibing ZHOU Dapeng wang yeguang GAO Wanxin ZHANG Yanjun AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

The stability margin is a vital indicator for assessing the safety level of aircraft control *** should maintain sufficient stability margin to ensure safety during flight,especially in the process of large maneuver *** stability margin is generally quantified by the Bode diagram,which strictly depends on the system parameters and the open-loop transfer ***,due to the uncertain flight environments,transmission delays of sensors and mode switchings,etc.,there exist large parameter and structure uncertainties in the aircraft control systems,which make it difficult to precisely configure the stability margin to the desired value by the usual control *** address this problem,an indirect adaptive control strategy is proposed in this paper,where an adaptive PI control law with the capability of self-configuration of stability margin is *** developed control law not only achieves stable time-varying command tracking in the time domain,but also is able to automatically configure the phase margin and gain margin in the frequency ***,the simulation of the one-degree-of-freedom roll rate control model of the air vehicle verifies the validity of the proposed control method.

关键词： Adaptive control aircraft control parameter uncertainty stability margin configuration

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基于通用化等效模型的飞机系统辨识算法

北京航空航天大学学报 2024年第5期50卷 1454-1462页

作者：周大鹏李贺琦王业光王立新北京航空航天大学航空科学与工程学院北京100191 中国航空工业沈阳飞机设计研究所沈阳110035

针对舰载机等复杂动力学系统的高阶时滞模型拟配难题,提出了一种基于通用化等效模型的系统频域辨识算法。建立系统辨识通用化等效模型,引入自适应学习率梯度下降法对模型进行基于样本的迭代学习训练,使模型的频域参数自动收敛,辨识得到... 详细信息

针对舰载机等复杂动力学系统的高阶时滞模型拟配难题,提出了一种基于通用化等效模型的系统频域辨识算法。建立系统辨识通用化等效模型,引入自适应学习率梯度下降法对模型进行基于样本的迭代学习训练,使模型的频域参数自动收敛,辨识得到复杂系统的高阶时滞模型。以舰载机横航向荷兰滚等效拟配模型进行验证,与传统算法对比,并分析了系统的频域与时域响应,结果表明:所提算法具有较好的辨识效果,解决了高阶时滞模型的直接拟配难题,并通用于广泛的高阶时滞模型拟配。

关键词：梯度下降法频域建模高阶时滞模型自适应学习率等效拟配

Evolution and deformability of inclusions in Al-killed steel with rare earth-alkali metals(Ca or Mg) combined treatment

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稀土学报:英文版 2023年第9期41卷 1459-1466,I0007页

作者： yeguang wang Chengjun Liu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Northeastern UniversityShenyang 110819China

The quality of stainless steel is closely related to the deformability of inclusions,which is significantly affected by their *** present study first inve stigated the evolution of inclusion compositions in AI-killed steel with rare earth-alkali metals(Ca or Mg)combined treatme nt through four laboratory-scale *** Ce contents in the final steel are 0.0080 wt%,0.015 wt%,0.016 wt%and 0.010 wt%,*** Mg content is 0.0014 wt%in Ce-Mg combined treated steel,and the Ca content is0.0015 wt%in Ce-Ca combined treated *** deformability of inclusions in both Ce_(2)O_(3)-Al_(2)O_(3)-CaO and Ce_(2)O_(3)-Al_(2)O_(3)-MgO systems was subsequently evaluated by calculating their Young's modulus at low *** results show that irregular Al_(2)O_(3)and MgAl_(2)O_(4)with poor deformability are modified to CeAlO_(3)and Ce_(2)O_(3)by Ce treatment,resulting in the decrease of Young's modulus of *** deformability of inclusions is further improved due to the transformation from lumped-like CeAlO_(3)to spherical CaO-Al_(2)O_(3)-Ce_(2)O_(3)caused by Ca treatment,and some of these inclusions are the ones with low liquidus *** analysis was used to discuss the control condition of the formation and evolution of ***,the appropriate addition amounts of Al,Mg,Ce,and Ca are expected to control inclusion compositions and properties,including deformability and liquidus temperature,thereby improving the steel performance.

关键词： Rare earths Alkali metals Inclusions evolution Inclusions deformability Thermodynamic analysis

Hydrothermal synthesis of calcium sulfate whisker from flue gas desulfurization gypsum

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Chinese Journal of Chemical Engineering 2016年第11期24卷 1552-1560页

作者： Chengjun Liu Qing Zhao yeguang wang Peiyang Shi Maofa Jiang Key Laboratory for Ecolocal Metallurgy of Multimetallic Ores (Ministry of Education) School of Metallurgy Northeastern University Shenyang 110819 China

Plenty of flue gas desulfurization(FGD) gypsum generated from coal-fired power plants for sulfur dioxide sequestration caused many environmental issues. Preparing calcium sulfate whisker(CSW) from FGD gypsum by hydrothermal synthesis is considered to be a promising approach to solve this troublesome problem and utilize calcium sulfate in a high-value-added way. The effects of particle size of FGD gypsum, slurry concentration,and additives on CSW were investigated in this work. The results indicated that fine particle size of FGD gypsum and moderately high slurry concentration were beneficial for crystal nucleation and growth. Three additives of magnesium chloride, citric acid, and sodium dodecyl benzene sulfonate(SDBS) were employed in this study. It was found that mean length and aspect ratio of CSW were both decreased by the usage of magnesium chloride,while a small quantity of citric acid or SDBS could improve the CSW morphology. When multi-additives of citric acid-SDBS were employed, the mean length and aspect ratio increased more than 20%. Moreover, surface morphology of CSW went better, and the particle size and crystal shape became more uniform.

关键词： Calcium sulfate whisker Hydrothermal Synthesis Environment

K405合金空心球泡沫的制备与压缩性能研究

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稀有金属材料与工程 2008年第1期37卷 135-138页

作者：李智伟王宏伟魏尊杰王叶广哈尔滨工业大学黑龙江哈尔滨150001

采用空心球法制备平均孔径约3mm、壁厚约0.1mm的K405合金空心球泡沫。首先在聚苯乙烯球上涂覆粉浆制备湿球,将其按体心立方结构排布,随后在真空条件下将堆跺好的球坯在300℃保温40min分解有机物,在1150℃保温150min烧结。制备的K405合... 详细信息

采用空心球法制备平均孔径约3mm、壁厚约0.1mm的K405合金空心球泡沫。首先在聚苯乙烯球上涂覆粉浆制备湿球,将其按体心立方结构排布,随后在真空条件下将堆跺好的球坯在300℃保温40min分解有机物,在1150℃保温150min烧结。制备的K405合金空心球泡沫的密度分别为0.987,0.999和1.085g/cm3;压缩试验结果表明:该泡沫试样的变形行为基本一致,屈服强度大于25MPa。

关键词：空心球金属泡沫 K405合金

高品质钢中稀土夹杂物聚合特征的在线观测分析

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钢铁研究学报 2022年第12期34卷 1379-1386页

作者：王野光刘承军东北大学多金属共生矿生态化冶金教育部重点实验室辽宁沈阳110819 东北大学冶金学院辽宁沈阳110819

高品质钢中大尺寸稀土夹杂物及其团簇的形成对浇注过程的工艺顺行与钢材产品质量均具有严重危害。为了研究高品质钢中稀土夹杂物的聚合特征,通过模拟实验研究了稀土处理不锈钢体系中夹杂物的成分演变,在此基础上,利用高温激光共聚焦显... 详细信息

高品质钢中大尺寸稀土夹杂物及其团簇的形成对浇注过程的工艺顺行与钢材产品质量均具有严重危害。为了研究高品质钢中稀土夹杂物的聚合特征,通过模拟实验研究了稀土处理不锈钢体系中夹杂物的成分演变,在此基础上,利用高温激光共聚焦显微镜对不同类型夹杂物的聚合行为进行了在线观测。研究结果表明,在铈处理铝脱氧钢中,随着夹杂物中Al2O3含量逐渐降低,Ce2O3含量逐渐升高,夹杂物由Al2O3转变为CeAlO3。在铈处理硅铝复合脱氧钢中,随着夹杂物中Ce2O3含量逐渐降低,SiO2含量逐渐升高,SiO2-Al2O3夹杂物逐渐转变为液相Ce2O3-SiO2-Al2O3夹杂物。固相Al2O3、SiO2-Al2O3和CeAlO3粒子在钢液中易聚合形成大尺寸团簇,导致夹杂物尺寸不断增大,液相Ce2O3-SiO2-Al2O3夹杂物不易聚合长大,其尺寸随观测时间的延长变化不大。实验条件下,钢中不同类型夹杂物的聚合趋势为:Al2O3>CeAlO3>SiO2-Al2O3>液相Ce2O3-SiO2-Al2O3。控制得到Ce2O3-SiO2-Al2O3夹杂物能够抑制大尺寸稀土夹杂物的形成,有望改善稀土钢的水口结瘤问题。

关键词：稀土夹杂物在线观察尺寸变化聚合特征

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基于LSTM的飞行数据挖掘模型构建方法

航空学报 2021年第8期42卷 255-264页

作者：王志刚王业光杨宁米禹丰曲晓雷航空工业沈阳飞机设计研究所沈阳110035

提出了一种基于LSTM(Long Short Time Memory)模型的飞行历史数据挖掘模型的构建方法,此模型可以将飞行数据中有价值的目标数据自动提取出来。首先,通过滑动窗口法获得待检测数据;然后,将预先做好的训练样本数据输入到所构造的LSTM模型... 详细信息

提出了一种基于LSTM(Long Short Time Memory)模型的飞行历史数据挖掘模型的构建方法,此模型可以将飞行数据中有价值的目标数据自动提取出来。首先,通过滑动窗口法获得待检测数据;然后,将预先做好的训练样本数据输入到所构造的LSTM模型中进行训练,得到数据挖掘模型;最后,将待检测数据导入到训练好的LSTM模型中进行模式识别,将目标数据片段挖掘出来。结果表明,基于LSTM模型的飞行数据挖掘模型构建方法通用化程度高,可用于挖掘不同类型的目标数据,且识别率高,具有很高的工程应用价值。

关键词： LSTM 飞行历史数据数据挖掘模式识别模型构建

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微创针刺旋切制备兔椎间盘退变模型

中国修复重建外科杂志 2016年第3期30卷 343-347页

作者：谭伟伟何升华孙志涛王业广王建赖居易安徽中医药大学研究生部合肥230000 深圳市中医院骨三科广州中医药大学

目的探讨微创针刺旋切制备兔椎间盘退变(intervertebral disc degeneration,IDD)模型的可行性。方法取40只新西兰大白兔,雌雄不限,体质量(2.9±0.3)kg;随机分为对照组和实验组(n=20)。对照组不予处理;实验组采用18G穿刺针在C臂X线机引... 详细信息

目的探讨微创针刺旋切制备兔椎间盘退变(intervertebral disc degeneration,IDD)模型的可行性。方法取40只新西兰大白兔,雌雄不限,体质量(2.9±0.3)kg;随机分为对照组和实验组(n=20)。对照组不予处理;实验组采用18G穿刺针在C臂X线机引导下经皮侧后方穿刺进入L4、5、L5、6椎间盘内,旋切髓核组织以促进椎间盘的退变。术后4、8、12、16周行大体观察、MRI观察并根据Pfirrmann分级法评价椎间盘退变情况,然后处死动物取材行Masson染色和番红O染色观察。结果实验组髓核组织颜色较对照组暗,弹性降低。对照组MRI T2加权像椎间盘信号强度早期未见明显改变,后期略减弱;实验组椎间盘信号强度随时间延长呈减弱趋势。根据Pfirrmann分级法评价椎间盘退变程度,两组随时间延长椎间盘退变程度均逐渐加重(P0.05)外,其余术后各时间点实验组椎间盘退变程度较对照组严重(P<0.05)。Masson染色示随时间延长,对照组纤维环出现排列不规整,但结构仍完整;实验组纤维环排列紊乱,甚至出现断裂现象。番红O染色示对照组髓核细胞未见明显减少,实验组髓核细胞明显减少。结论微创针刺旋切法可成功制备兔IDD模型。

关键词：微创造模针刺旋切椎间盘退变兔

《条例》颁布后县区计划生育服务站的生存与发展

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中国计划生育学杂志 2002年第2期10卷 78-79页

作者：葛秀英王野光吉林省松原市计生委办公室 131100 吉林省松原市前郭县计划生育药具站

《计划生育技术服务管理条例》(以下简称《条例》)的颁布实施,以法规形式明确了计划生育服务网络的法律地位和服务范围。它为计划生育技术服务机构围绕生育、节育、不育开展服务提供了法律依据,同时也明确了计划生育服务部门履行监督管... 详细信息

《计划生育技术服务管理条例》(以下简称《条例》)的颁布实施,以法规形式明确了计划生育服务网络的法律地位和服务范围。它为计划生育技术服务机构围绕生育、节育、不育开展服务提供了法律依据,同时也明确了计划生育服务部门履行监督管理的法律授权。《条例》的颁布和实施,结束了长期以来计划生育服务工作在国家一级没有法律规范的历史,标志着我国的计划生育技术服务工作开始进入依法管理、规范服务、有序发展的新阶段。

关键词：计划生育服务站计划生育技术服务县区生存与发展

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan wang Jiang wang Shaoming HE Fei wang Qi wang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence