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A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： Tao hao School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

薄壁构件镜像加工支撑机构综合刚度的分析与优化

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机械设计与研究 2015年第2期31卷 155-159,163页

作者：郝金明赵勇王皓盛东义上海交通大学上海市复杂薄板数字化制造重点实验室上海200240 上海交通大学机械系统与振动国家重点实验室上海200140

薄壁构件的工件刚度随着装夹布局的变化而变化,在构件的不同位置,其刚度也是变化的。镜像加工装备是针对薄壁构件加工而设计的一种新型加工装备,其支撑机构可以起到对系统刚度的调节作用,支撑机构和工件的综合刚度变化越小,加工精度一... 详细信息

薄壁构件的工件刚度随着装夹布局的变化而变化,在构件的不同位置,其刚度也是变化的。镜像加工装备是针对薄壁构件加工而设计的一种新型加工装备,其支撑机构可以起到对系统刚度的调节作用,支撑机构和工件的综合刚度变化越小,加工精度一致性越高。针对自主设计的新型镜像支撑设备,建立了镜像支撑机构和工件的刚度模型,计算了综合刚度在加工表面的分布,并通过增加冗余驱动的方式优化综合刚度,结果表明优化后的整机平均支撑刚度提高大约1倍,综合刚度最小值提高37.6%,且分布更加均匀。

关键词：镜像支撑刚度分析冗余驱动刚度优化

Machine learning-assisted smart epitaxy ofⅢ-Ⅴsemiconductors

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Science China Materials 2024年第9期67卷 3041-3042页

作者： Yue hao Key Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an710071China

Semiconductor epitaxial growth is the front-end process for manufacturing microelectronic and optoelectronic *** beam epitaxy(MBE),capable of precisely controlling atomic layer deposition,has emerged as a crucial technique in chip atomic-level manufacturing[1].However,in semiconductor epitaxy,the heterogeneous nature of materials is complicated,and the growth condition fluctuations poses significant challenges in defect suppression[2],substantially impacting chip performance and yield.

关键词： optoelectronic smart semiconductors

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一种伪随机脉冲的快速参数估计方法

武汉大学学报（信息科学版） 2015年第11期40卷 1487-1492页

作者：刘伟平郝金明田英国于合理信息工程大学导航与空天目标工程学院河南郑州450001

在精密定轨中,附加伪随机脉冲能够很好地弥补力学模型精度不足的问题,然而由于伪随机脉冲数量通常较多,如果利用常规最小二乘方法直接进行参数估计,会严重降低计算效率。针对这一问题,给出了一种基于参数预消除与回代思想的伪随机脉冲... 详细信息

在精密定轨中,附加伪随机脉冲能够很好地弥补力学模型精度不足的问题,然而由于伪随机脉冲数量通常较多,如果利用常规最小二乘方法直接进行参数估计,会严重降低计算效率。针对这一问题,给出了一种基于参数预消除与回代思想的伪随机脉冲参数快速估计方法,实测算例表明,利用本文方法,能够获得与常规最小二乘方法相同的参数估值,但本文方法在计算效率上要明显优于后者。

关键词：伪随机脉冲参数快速估计参数预消除力学模型精密定轨

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北斗卫星多天轨道合成方法及其精度分析

测绘学报 2016年第10期45卷 1157-1164页

作者：刘伟平郝金明于合理田英国信息工程大学导航与空天目标工程学院河南郑州450001

目前,北斗卫星多天解轨道主要是通过常规的数据累积解算获得,处理效率较低。此外,由于开通运行不久,北斗卫星力学模型尚未完善,限制了多天解轨道精度的进一步提高。针对以上问题,本文提出了附加伪随机脉冲的北斗卫星多天轨道合成方法,... 详细信息

目前,北斗卫星多天解轨道主要是通过常规的数据累积解算获得,处理效率较低。此外,由于开通运行不久,北斗卫星力学模型尚未完善,限制了多天解轨道精度的进一步提高。针对以上问题,本文提出了附加伪随机脉冲的北斗卫星多天轨道合成方法,利用法方程叠加实现北斗卫星多天轨道合成,可有效提高轨道解算效率。同时,利用伪随机脉冲对力学模型的补偿作用,进一步提高了多天轨道合成的精度水平。实测数据分析表明:在多天轨道合成中,单天边界附加伪随机脉冲对北斗卫星轨道精度有明显改进作用。其中,3类卫星切向、法向轨道精度的改善程度大于径向,GEO和IGSO卫星轨道精度的提高幅度大于MEO卫星。一定范围内,随着定轨弧段的增长,北斗卫星定轨精度能够得到不同程度的改善,且主要表现在轨道切向。

关键词：北斗卫星导航系统精密定轨法方程叠加轨道合成伪随机脉冲

不同数据预处理方法对北斗卫星精密定轨精度的影响

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大地测量与地球动力学 2011年第6期31卷 84-88页

作者：周巍郝金明贾小林解放军信息工程大学测绘学院中国人民解放军63883部队西安测绘研究所

提出综合利用高次差法和多项式拟合法对COMPASS-MEO卫星进行周跳探测的原理及实现方法,并采用COMPASS监测站实测数据使用不同的数据预处理策略对COMPASS-MEO卫星进行精密定轨试验。结果表明,根据实测数据情况,合理选择周跳探测方法和预... 详细信息

提出综合利用高次差法和多项式拟合法对COMPASS-MEO卫星进行周跳探测的原理及实现方法,并采用COMPASS监测站实测数据使用不同的数据预处理策略对COMPASS-MEO卫星进行精密定轨试验。结果表明,根据实测数据情况,合理选择周跳探测方法和预处理策略,可以改善定轨精度。

关键词： COMPASS 周跳 φLC-PLC组合多项式拟合定轨

A review on numerical studies of airflow dynamics and particle deposition in human respiratory system Author links open overlay panel

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Particuology 2024年第8期91卷 351-377页

作者： hao Jing Xinguang Cui School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China

Accurate assessment and prediction of airflow dynamics and particle deposition in the human respiratory tract are essential for human health,involving inhaled drugs for treating various diseases and toxic particles that can cause *** intricate process involves complex multiphase flow with distinct respiratory *** fluid dynamics(CFD)acts as a bridge,overcoming the limitations of in vivo and in vitro experiments and providing a means to fully comprehend and reveal the fundamental mechanisms of respiratory flow and particle behavior on a microscopic *** paper provides a comprehensive overview and concise summary of recent advancements in the numerical simulation of airflow and particle deposition in the human respiratory ***,it summarizes the transition of respiratory tract models from segmented models to emerging physiological characteristic models and whole-lung airway models,and the latest developments on the effects of key factors such as geometric variations,respiratory patterns,and particle physical/chemical properties on respiratory flow and particle deposition.A notable focus of this review is on emerging physiological characteristics models and their associated complex airflow and particle dynamics inside *** paper concludes with recommendations for future research to further advance the development of this field.

关键词： Airflow dynamics Particle deposition Human respiratory system Numerical modeling

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a Lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： ZHOU hao HU Liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 L/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

Scalar Weighed Least Square Combination Model for Clock Offset Prediction

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Scalar Weighed Least Square Combination Model for Clock Offs...