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控制理论与应用（英文版） 2011年第2期9卷 302-306页

作者： jianwei xia 1,2,hongbin zhang 3 1.school of automation,southeast university,nanjing jiangsu 210096,china 2.school of Mathematics Science,Liaocheng university,Liaocheng Shandong 252000,china 3.school of Electronic Engineering,university of Electronic Science and Technology,Chengdu Sichuan 610054,china school of automation Southeast University Nanjing Jiangsu China school of Mathematics Science Liaocheng University Liaocheng Shandong China school of Electronic Engineering University of Electronic Science and Technology Chengdu Sichuan China

The global robust exponential stability of a class of neural networks with polytopic uncertainties and distributed delays is investigated in this ***-dependent Lypaunov-Krasovskii functionals and free-weighting matrices are employed to obtain sufficient condition that guarantee the robust global exponential stability of the equilibrium point of the considered neural *** derived sufficient condition is proposed in terms of a set of relaxed linear matrix inequalities (LMIs),which can be checked easily by recently developed algorithms solving LMIs.A numerical example is given to demonstrate the effectiveness of the proposed criteria.

关键词： Neural networks Polytopic uncertainties Distributed delays Delay-dependent Global robust exponential stability

Simultaneous enhancements of strength and toughness by multiscale lamellar structure in Ti_(2)AlNb based intermetallic

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Journal of Materials Science & Technology 2024年第7期174卷 249-261页

作者： Fan zhang Weidong Zeng Penghui zhang Haoyuan Ma jianwei Xu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Defense Technologies Innovation Center of precision forging and ring rolling School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Multi-scale lamellar structure significantly improves toughness of Ti_(2)AlNb based alloys,which are inher-ently brittle intermetallics,without compromising their *** structure was achieved through-B2-transus-forging(TBTF)combined with O+B2 two-phase region heat *** types of multi-scale lamellar structures were obtained by controlling the cooling rate after *** variations were mainly attributed to differences in the distribution,content,and size of the thick lamellar O phase and the size and crystallographic orientation of B2 *** analyzing the microstructural characteristics and crystallographic orientation near the crack propagation path,it was found that the crack propaga-tion resistance of thick lamellae,sub grain and grain boundaries(GBs)O phase increased sequentially,accompanied by more tortuous crack propagation ***,B2 grains with high misorientation significantly deflected the crack propagation by cleavage ridges between adjoining cleavage ***-tionally,the development of numerous secondary cleavage ridges,resulting from the transition through varying secondary cleavage planes in distinct sub B2 grains,further hindered the quick propagation of *** was clarified that the cleavage planes were dominantly belonging to{110}.These findings pro-vided valuable guidance for the design of damage tolerance strategies for Ti_(2)AlNb-based intermetallics.

关键词： Multiscale lamellae structure Fracture toughness Crack propagation Ti_(2)AlNb-based intermetallic Through-B2-transus-forging

Machine Learning Security Defense Algorithms Based on Metadata Correlation Features

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Computers, Materials & Continua 2024年第2期78卷 2391-2418页

作者： Ruchun Jia jianwei zhang Yi Lin College of Computer Science Sichuan UniversityChengdu610065China

With the popularization of the Internet and the development of technology,cyber threats are increasing day by *** such as malware,hacking,and data breaches have had a serious impact on *** network security environment in the era of big data presents the characteristics of large amounts of data,high diversity,and high real-time *** security defense methods and tools have been unable to cope with the complex and changing network security *** paper proposes a machine-learning security defense algorithm based on metadata association *** control over unauthorized users through privacy,integrity,and *** user model is established and the mapping between the user model and the metadata of the data source is *** analyzing the user model and its corresponding mapping relationship,the query of the user model can be decomposed into the query of various heterogeneous data sources,and the integration of heterogeneous data sources based on the metadata association characteristics can be *** and classify customer information,automatically identify and perceive sensitive data,build a behavior audit and analysis platform,analyze user behavior trajectories,and complete the construction of a machine learning customer information security defense *** experimental results show that when the data volume is 5×103 bit,the data storage integrity of the proposed method is 92%.The data accuracy is 98%,and the success rate of data intrusion is only 2.6%.It can be concluded that the data storage method in this paper is safe,the data accuracy is always at a high level,and the data disaster recovery performance is *** method can effectively resist data intrusion and has high air traffic control *** can not only detect all viruses in user data storage,but also realize integrated virus processing,and further optimize the security defense effect of user big data.

关键词： Data-oriented architecture metadata correlation features machine learning security defense data source integration

Approximate Synchronization of Multi-Agent Systems over Finite Fields

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Journal of Systems Science & Complexity 2024年第4期37卷 1561-1580页

作者： YU Miao FENG Jun-e xia jianwei FU Shihua SHEN Hao school of Mathematical Sciences Liaocheng UniversityLiaocheng 252059China school of Mathematics Shandong UniversityJinan 250100China school of Electrical and Information Engineering Anhui University of TechnologyMaanshan 243002China

In this paper,the approximate synchronization of leader-follower multiagent systems(MASs) over finite fields is studied in regard to local and global ***,the approximately synchronous state set(ASSS) is ***,combined with ASSS and transient periods,some criteria for the local and global approximate synchronization of systems are ***,the algorithms for calculating the maximum approximately synchronous basin(MASB) and the maximum control invariant set(MCIS) are ***,the global approximate synchronization of the system is achieved by designing the state feedback control,and a design algorithm of the controller using the truth matrix method is ***,the results of approximate synchronization are degenerated to complete ***,two examples are shown to demonstrate the results of this paper.

关键词： Approximate synchronization finite field multiagent system semi-tensor product state feedback control

A rapid assessment of MWRI-RM/FY3G brightness temperature

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 42-46页

作者： Wenying He Xinran xia Shengli Wu Peng zhang hongbin Chen xiang'ao xia Yuquan Zhou Miao Cai LAGEO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina school of Hydrology and Water Resources Nanjing University of Information Science&TechnologyNanjingChina National Satellite Meteorological Centure Chinese Meteorological AdministrationBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Key Laboratory of Cloud-Precipitation Physics and Weather Modification CMABeijingChina

2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式... 详细信息

2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式进行双差分(DD)交叉定标分析,旨在快速评估新一代MWRI-RM观测数据质量.观测比较表明,MWR1-RM与GMI测量的Tb一致性很好,大多通道的平均偏差(MBE)和均方根误差(RMSE)均小于1K.两种传感器由于观测角度略有不同在水面产生约0.5 K差异.DD分析也展示出MWRI-RM的大多数通道性能与GMI相当接近,尤其是首次启用的高频166 GHz和183 GHz.

关键词： FY3G MWRI-RM GMI 亮度温度双差分方法

Seasonal thermal energy storage using natural structures:GIS-based potential assessment for northern china

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Building Simulation 2024年第4期17卷 561-574页

作者： Yichi zhang Jianjun xia Midea HVAC Heating&Ventilation Equipment Co. LtdFoshan528311China Building Energy Research Center Tsinghua UniversityBeijing100084China

Seasonal thermal energy storage(STES)allows storing heat for long-term and thus promotes the shifting of waste heat resources from summer to winter to decarbonize the district heating(DH)*** being a promising solution for sustainable energy system,large-scale STES for urban regions is lacking due to the relatively high initial investment and extensive land *** close the gap,this study assesses the potentials of using two naturally available structures for STES,namely valley and ground pit *** on geographical information system(GIS)methods,the available locations are searched from digital elevation model and selected considering several criteria from land uses and construction *** costs of dams to impound the reservoir and the yielded storage capacities are then quantified to guide the choice of suitable *** assessment is conducted for the northern china where DH systems and significant seasonal differences of energy demand *** total,2,273 valley sites and 75 ground pit sites are finally identified with the energy storage capacity of 15.2 billion GJ,which is much larger than the existing DH demand in northern *** results also prove that 682 valley sites can be achieved with a dam cost lower than 20 CNY/m^(3).By conducting sensitivity analysis on the design dam wall height and elevations,the choices of available natural structures are expanded but practical issues about water pressures and constructions are also ***,the identified sites are geographically mapped with nearest urban regions to reveal their roles in the DH *** general,560 urban regions are found with potential STES units and most of them have STES storage capacities larger than their own DH *** novel planning methodology of this study and publicly available datasets create possibilities for the implementations of large-scale STES in urban DH systems.

关键词： seasonal thermal energy storage geographical information system district heating water reservoir

Strategy for suppressing abnormal grain growth of ZK60 Mg alloy during solution by pre-compression:A quasi-in-situ study

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Journal of Materials Science & Technology 2024年第4期171卷 115-128页

作者： Zhenxu Wang Liang Chen jianwei Tang Cunsheng zhang Guoqun Zhao Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinanShandong 250061China Department of Mechanical Engineering Kyushu UniversityFukuoka 819-0395Japan

Abnormal grain growth(AGG)easily takes place in Mg alloys during high-temperature solutions,result-ing in deterioration of mechanical ***,the compression prior to solution(pre-compression)was conducted to suppress AGG,and the microstructure evolution as well as suppressing mechanisms was investigated based on quasi-in-situ *** compression along the transverse direction,11-20>//ED grains preferentially nucleated and rapidly grew up,and the initial10-10>//ED texture was *** grain growth modes of heat-induced and strain-induced grain boundary migrations were *** former was attributed to the high interfacial energy of grain boundaries with large *** latter consumed the adjacent grains with high storage energy,forming abnormal grains with irregular *** compression with a reduction>6%could obviously suppress *** suppressing effects were mainly attributed to weakening the size advantage of11-20>//ED grains,increasing nucleation,reducing grain boundary character distribution,and redistributing storage energy *** 12%compression along the transverse direction,30°misorientation of11-20>//ED grains and high energy grain boundaries were ***{10-12}tensile twins and{10-15}high index twins induced by com-pression increased the nucleation of static ***,compression introduces high-density dislocations,which also contributed to suppressing AGG behavior during solution.

关键词： Quasi-in-situ analysis Mg alloy Abnormal grain growth Compression Microstructure

Distributed power conditioning unit of large-scale space solar power station

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Chinese Journal of Aeronautics 2024年第8期37卷 421-434页

作者： Xintong LI jianwei MI Yiqun zhang Guanheng FAN Jie DU school of Mechano-electronic Engineering Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Space Solar Power Station System Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China

In this paper,a multi-bus distributed Power Conditioning Unit(PCU)is proposed for the Space Solar Power Station with large scale photovoltaic(PV)array and power levels reaching MW *** this unit,there are multiple independent PV *** each PV array,there are multiple independent PV *** this paper,a V-P droop control method with adaptive droop coefficient is proposed,which modifies the droop intercept based on the bus voltage deviation and the power per unit value of the PV *** method ensures the accuracy of bus voltage and achieves proportional distribution of power between PV arrays based on the proposed topology structure in this *** the load changes or the output power of the PV array fluctuates,this method can ensure that power is distributed *** principle and control method of the proposed droop control method is analyzed in this *** effectiveness of the method is verified through MATLAB/Simulink simulation and *** and experimental results show that the proposed method can achieve power distributed proportionally when load changes and PV output power fluctuates,reduce bus voltage error caused by line impedance and differences in rated power of different PV arrays,and improve the performance of PV power generation system applied to space.

关键词： Space Solar Power Station Photovoltaics Droop control DC confluence Power conditioning unit

Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target

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Defence Technology（防务技术） 2024年第2期32卷 104-119页

作者： Fei zhang Xingling Shao Yi xia Wendong zhang National Key Laboratory for Electronic Measurement Technology School of Instrument and ElectronicsNorth University of ChinaTaiyuan030051China

Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external ***,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still *** this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching *** remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence ***,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational *** tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm.

关键词： Elliptical encirclement Reinforced performances Wind perturbations UAVs

Mesoporous polymers:soft-template self-assembly synthesis and applications

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Science china Chemistry 2024年第5期67卷 1442-1464页

作者： Facai Wei Tingting zhang jianwei Fu Chengbin Jing Jiangong Cheng Shaohua Liu State Key Laboratory of Precision Spectroscopy Engineering Research Center of Nanophotonics&Advanced Instrument(Ministry of Education)School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China school of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Mesoporous polymers combine the advantages of polymer materials(abundant polar functional groups,lightweight,flexibility,and processability)and mesoporous structures(high specific surface area,adjustable pore structure,and large pore volume);hence,they have great application potential in sensing,adsorption,catalysis,energy storage,biomedicine,***,developing advanced synthetic strategies for mesoporous polymers and investigating their intrinsic applications have become hot research ***-template-based self-assembly is regarded as a promising approach for synthesizing mesoporous *** work reviews recent progress in the synthetic strategy for producing various mesoporous polymers using soft-template selfassembly,focusing on the synthesis of conductive polymers,phenol-based polymers,and resin-based polymers and their potential ***,perspectives on future applications of mesoporous polymers,along with a few challenges that need to be resolved,are also discussed in this review.

关键词： mesoporous polymer porous material self-assembly soft templates interface synthesis