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基于走航观测评估大气再分析中的南大洋大气河

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高原气象 2025年第1期44卷 83-94页

作者：项旭韩博张功刘长炜梁凯昕齐木荣江可悦林奕辰钟锐杨清华中山大学大气科学学院和南方海洋科学与工程广东省实验室(珠海) 广东珠海519082

大气河直接影响南极海-陆-冰-气相互作用,但对其开展的探空观测尚不多,造成数值模式和再分析数据的结论存在不确定性。本研究使用了中国第37次南极科考获得的走航探空数据,针对一次南大洋大气河事件评估了4种大气再分析数据——ERA5,CFS... 详细信息

大气河直接影响南极海-陆-冰-气相互作用,但对其开展的探空观测尚不多,造成数值模式和再分析数据的结论存在不确定性。本研究使用了中国第37次南极科考获得的走航探空数据,针对一次南大洋大气河事件评估了4种大气再分析数据——ERA5,CFSv2,JRA-55和MERRA-2。评估结果表明:虽然所有大气再分析数据对南大洋水汽通量(IVT)的描述都与观测比较接近——包括在大气河期间,但这部分是因为再分析数据高估了大气整层(地表至300 hPa)湿度场的同时低估了大气整层风速。进一步分析发现,大气湿度和风速在垂直方向的协变项被多数再分析数据显著低估甚至给出了与观测相反的结果;而协变项的偏差对IVT影响与整层大气湿度和风速相当。ERA5在协变项的表现显著优于其他再分析数据。与此同时,ERA5也给出了大气河期间与观测最为一致的逆湿和低空急流结构。因此,仅就本次观测而言ERA5对南大洋大气河的描述能力是最佳的。

关键词：南大洋大气河无线电探空大气再分析

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Reentry trajectory rapid optimization for hypersonic vehicle satisfying waypoint and no-fly zone constraints

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1277-1290页

作者： Lu Wang qinghua Xing Yifan Mao School of Air and Missile Defense Air Force Engineering University

To rapidly generate a reentry trajectory for hypersonic vehicle satisfying waypoint and no-fly zone constraints, a novel optimization method, which combines the improved particle swarm optimization （PSO） algorithm with the improved Gauss pseudospectral method （GPM）, is proposed. The improved PSO algorithm is used to generate a good initial value in a short time, and the mission of the improved GPM is to find the final solution with a high precision. In the improved PSO algorithm, by controlling the entropy of the swarm in each dimension, the typical PSO algorithm＇s weakness of being easy to fall into a local optimum can be overcome. In the improved GPM, two kinds of breaks are introduced to divide the trajectory into multiple segments, and the distribution of the Legendre-Gauss （LG） nodes can be altered, so that all the constraints can be satisfied strictly. Thereby the advan- tages of both the intelligent optimization algorithm and the direct method are combined. Simulation results demonstrate that the proposed method is insensitive to initial values, and it has more rapid convergence and higher precision than traditional ones.

关键词： hypersonic vehicle (HV) reentry trajectory optimization waypoint no-fly zone particle swarm optimization (PSO),Gauss pseudospectral method (GPM).

An Air Defense Weapon Target Assignment Method Based on Multi-Objective Artificial Bee Colony Algorithm

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Computers, Materials & Continua 2023年第9期76卷 2685-2705页

作者： Huaixi Xing qinghua Xing Air and Missile Defense College Air Force Engineering UniversityXi’an710051China

With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target *** achieve high-efficiency and lowloss defensive operations,a reasonable air defense weapon assignment strategy is a key *** this paper,a multi-objective and multi-constraints weapon target assignment(WTA)model is established that aims to minimize the defensive resource loss,minimize total weapon consumption,and minimize the target residual *** optimization framework of air defense weapon mission scheduling based on the multiobjective artificial bee colony(MOABC)algorithm is *** solution for point-to-point saturated attack targets at different operational scales is achieved by encoding the nectar with real *** are performed for an imagined air defense scenario,where air defense weapons are *** non-dominated solution sets are obtained by the MOABC algorithm to meet the operational *** the case where there are more weapons than targets,more diverse assignment schemes can be *** to the inverse generation distance(IGD)index,the convergence and diversity for the solutions of the non-dominated sorting genetic algorithm III(NSGA-III)algorithm and the MOABC algorithm are compared and *** results prove that the MOABC algorithm has better convergence and the solutions are more evenly distributed among the solution space.

关键词： Weapon target assignment multi-objective artificial bee colony air defense defensive resource loss total weapon consumption target residual effectiveness

A 5-DOF Model for Aeroengine Spindle Dual-rotor System Analysis

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Chinese Journal of Aeronautics 2011年第2期24卷 224-234页

作者： HU qinghua DENG Sier TENG Hongfei School of Mechanical Engineering Dalian University of Technology Dalian 116024 China School of Mechatronics Engineering Henan University of Science and Technology Luoyang 471003 China

This paper develops a five degrees of freedom（5-DOF） model for aeroengine spindle dual-rotor system dynamic *** this system,the dual rotors are supported on two angular contact ball bearings and two deep groove ball bearings,one of the latter-mentioned bearings works as the inter-shaft *** by respective motors,the dual rotors have different co-rotating *** proposed model mathematically formulates the nonlinear displacements,elastic deflections and contact forces of bearings with consideration of 5-DOF and coupling of dual *** nonlinear equations of motions of dual rotors with 5-DOF are solved using Runge-Kutta-Fehlberg *** order to investigate the effect of the introduced 5-DOF and nonlinear dy-namic bearing model,we compare the proposed model with two models：the 3-DOF model of this system only considering three translational degrees of freedom（Gupta,1993,rotational freedom is neglected）;the 5-DOF model where the deep groove ball bearings are simplified as linear elastic spring（Guskov,2007）.The simulation results verify Gupta＇s prediction（1993） and show that the rotational freedom of rotors and nonlinear dynamic model of bearings have great effect on the system dynamic *** quantitative results are given as well.

关键词： aeroengine dual-rotor ball bearing nonlinear dynamics five degrees of freedom

Neural Network Compact Ensemble and Its Applications

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 209-216页

作者： WANG qinghua ZHANG Youyun ZHU Yongsheng Key Laboratory for Modern Design and Rotor-Bearing System of Ministry of Education Xi ＇an Jiaotong University Xi＇an 710049 China School of Mechatronic Engineering Xi＇an Technological University Xi＇an 710032 China

There has been many methods in constructing neural network （NN） ensembles, where the method of simultaneous training has succeed in generalization performance and efficiency. But just like regular methods of constructing NN ensembles, it follows the two steps, first training component networks, and then combining them. As the two steps being independent, an assumption is used to facilitate interactions among NNs during the training stage. This paper presents a compact ensemble method which integrates the two steps of ensemble construction into one step by attempting to train individual NNs in an ensemble and weigh the individual members adaptively according to their individual performance in the same learning process. This provides an opportunity for the individual NNs to interact with each other based on their real contributions to the ensemble. The classification performance of NN compact ensemble （NNCE） was validated through some benchmark problems in machine learning, including Australian credit card assessment, pima Indians diabetes, heart disease, breast cancer and glass. Compared with other ensembles, the classification error rate of NNCE can be decreased by 0.45% to 68%. In addition, the NNCE was applied to fault diagnosis for rolling element bearing. The 11 time-domain statistical features are extracted as the properties of data, and the NNCE is employed to classify the data. With the results of several experiments, the compact ensemble method is shown to give good generalization performance. The compact ensemble method can recognize the different fault types and various fault degrees of the same fault type.

关键词： neural network compact ensemble(NNCE) combination weights classification performance fault diagnosis

Near-Field Source Localization Using Spherical Microphone Arrays

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Chinese Journal of Electronics 2016年第1期25卷 159-166页

作者： HUANG qinghua ZHANG Guangfei LIU Kai Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

A new method is proposed for joint range and bearing(azimuth and elevation) estimation of multiple near-field acoustic sources using observations collected by a spherical microphone array. First, Spherical Fourier transform(SFT) is used to construct the array signal model in the spherical harmonics domain to decouple range and bearing information. Then the relation among the spherical harmonics of three adjacent degrees is exploited to build the recursive relationship of the signal subspace. Using Eigenvalue decomposition(EVD), bearings are estimated based on the eigenvalues and simultaneously the steering matrix can be represented by the signal ***, range is estimated using the energy ratios of the elements of the steering matrix in the spherical harmonics domain. The algorithm can avoid parameter pairing and multi-dimensional searching. It has lower computational complexity than that of the Multiple signal classification(MUSIC) method. The performance is evaluated by Monte-Carlo simulations and the estimation root meansquare errors are compared to the corresponding CramerRao bounds(CRBs) and those of MUSIC range estimates,which demonstrate the validity of the proposed algorithm.

关键词： Spherical microphone array Source localization Near-field Spherical Fourier transform(SFT) Spherical harmonics

Effects of Qingguang'an(青光安)containing serum on the expression levels of autophagy-related genes in human Tenon's fibroblasts induced by transforming growth factor beta 1

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Journal of Traditional Chinese Medicine 2021年第2期41卷 236-245页

作者： YU Juan XIA Fei LI xiang PENG qinghua Ophthalmology Department the First Affiliated HospitalHunan University of TCMChangsha 410007China Eye Research Centre Hunan University of Traditional Chinese MedicineChangsha 410208China Hunan Provincial Key Laboratory for the Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Traditional Chinese Medicine Changsha 410208China

OBJECTIVE:To explore the effects of Qingguang'an(青光安)containing serum on the expression levels of autophagy related genes in the transforming growth factor beta 1(TGF-β1)-activated human Tenon's fibroblasts(HTFs).METHODS:(a)Primary HTFs were stimulated by TGF-β1 and underwent immunohistochemistry,which established a cell model after Glaucoma filtration surgery(GFS).(b)The cell models were divided into 4 group:normal group(normal cells),model group(+TGF-β1),treatment group(+TGF-β1+medicated serum),and positive control group(TGF-β1+rapamycin).Then,Qingguang'an medicated serum with optimum concentration was added to the corresponding *** autophagy positive cells were identified by the Cyto-ID autophagy detection kits under fluorescent microscope and Cytation 5 multifunctional instrument for cell *** the mean fluorescence intensity of autophagy positive cells was determined by flow *** expression levels of autophagy related genes—Beclin-1,autophagy related gene 5(ATG-5),and microtubule-associated protein 1 light chain 3(LC-3Ⅱ)were detected by quantitative reverse transcription-polymerase chain reaction and Western blot ***:Compared with the normal group and the model group,the relative mRNA expression levels of autophagy-related genes(Beclin-1,ATG-5 and LC-3Ⅱ)in the experimental group were notably increased(P<0.05,P<0.01),and with the extension of treatment time,it had an increasing trend(48 h was more obvious),which showed a certain time dependency;the protein expression levels of autophagy-related genes(Beclin-1,ATG-5,and LC-3Ⅱ)were significantly increased in the experimental group(P<0.05,P<0.01).With the prolongation of treatment time,there was an increasing trend(48 h was relatively obvious),and it revealed a certain time dependency CONCLUSION:The Qingguang'an medicated serum could up-regulate autophagy related genes(Beclin1,ATG5,and LC3Ⅱ)in the TGF-β1-activated HTFs.

关键词： Qingguang'an medicated serum Transforming growth factor beta 1 beclin-1 autophagy-related protein 5 microtubule-associated proteins Human Tenon's fibroblasts

Multi-dimensional EEF Criterion for Source Number Estimation

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Chinese Journal of Electronics 2014年第3期23卷 503-507页

作者： HUANG qinghua WANG Tong School of Communication and Information Engineering Shanghai University Institute of Computer and Information Shanghai Second Polytechnic University

When the number of snapshots is smaller than the dimension of the measured data, Exponential embedded family(EEF) rule fails to choose the correct model order. It is modified in this paper to enumerate sources in three-dimensional space unlimited by the number of snapshots. Then the modified EEF criterion is extended to RD version for the multi-dimensional data model based on Higher-order singular value decomposition(HOSVD). The R-D EEF criterion exploits the multi-dimensional structure of measurements and the eigenvalues of different mode sample covariance matrices jointly. It improves accuracy and robustness compared with the modified EEF criterion. Simulation results demonstrate the performance of the proposed enumerators.

关键词： Source enumeration Exponential embedded family Multi-dimensional structure Tensor model

Optimal Integrated Schedule of Entire Process of Dual-blade Multi-cluster Tools From Start-up to Close-down

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 553-565页

作者： qinghua Zhu Yan Qiao Naiqi Wu IEEE the School of Computer Science and Technology Guangdong University of Technology the Helen and John C. Hartmann Department of Electrical and Computer Engineering New Jersey Institute of Technology the Institute of Systems Engineering Macao University of Science and Technology the National Key Laboratory of Precise Electronic Manufacturing Technology and Equipment Guangdong University of Technology

Multi-cluster tools are widely used in majority of wafer fabrication processes in semiconductor industry. Smaller lot production, thinner circuit width in wafers, larger wafer size, and maintenance have resulted in a large quantity of their start-up and close-down transient periods. Yet, most of existing efforts have been concentrated on scheduling their steady *** from such efforts, this work schedules their transient and steady-state periods subject to wafer residency constraints. It gives the schedulability conditions for the steady-state scheduling of dual-blade robotic multi-cluster tools and a corresponding algorithm for finding an optimal schedule. Based on the robot synchronization conditions, a linear program is proposed to figure out an optimal schedule for a start-up period, which ensures a tool to enter the desired optimal steady state. Another linear program is proposed to find an optimal schedule for a closedown period that evolves from the steady state period. Finally,industrial cases are presented to illustrate how the provided method outperforms the existing approach in terms of system throughput improvement.

关键词： Multi-cluster tools robots scheduling transient periods semiconductor manufacturing systems