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BEAM SHAPING BY MOVING THE PHASE CENTER OF ARRAY ANTENNA

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BEAM SHAPING BY MOVING THE PHASE CENTER OF ARRAY ANTENNA

1998 International Conference on Microwave and Millimeter Wave Technology

作者： Junaid Ul Islam Syed College of aeronautical Engineering National University of Science and TechnologyPakistan

＜正＞1 Introduction The phase pattern of an antenna can be expressed with reference to an arbitrary point in space such that the phase over the range of directions of interest becomes *** point is called the phase center of the array,from where the antenna radiation appears to *** general,an antenna does not have a unique phase center for all the

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Airport Management—Value of Customer Display Systems

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Intelligent Information Management 2015年第5期7卷 260-267页

作者： Adam Marks Maytha AL-Ali Kees Rietsema Zayed University Dubai UAE College of Business Embry-Riddle Aeronautical University Daytona Beach USA

By providing real-time updates of essential information, airports not only display and disseminate information but also help control the flow of traffic. In order to maximize available space, particularly in high traffic areas, Airport Display Information Systems should be integrated into the overall design of the airport and their positioning should be carefully planned to deliver optimal results. Airport Display Information Systems can help airports maximize space, increase customer satisfaction, and generate new revenue opportunities. The technology is designed not only to comply with environmental regulations, but also to help airports keep budgets in check. This paper discusses airport display systems, their connections and interoperability with other systems and who the key airport users of these airport display systems are.

关键词： Airport Aviation Management Information Systems Customer Display

Constitutionally adaptive crown ether-based macrocyclic bolaamphiphile with redox-responsive switching of lower critical solution temperature behaviors

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Chinese Chemical Letters 2021年第12期32卷 4024-4028页

作者： Qiangqiang Xu Zhiliyu Cui Jizhen Yao Bo Li Ping Lv Xin Shen Zhuo Yu Yan Ge Zhenhui Qi Sino-German Joint Research Lab for space Biomaterials and Translational Technology Synergetic Innovation Center of Biological Optoelectronics and Healthcare Engineering(BOHE)Xi'an 710072China

Constitutionally adaptive chemistry of selenium-containing crown ethers(CEs) offers a new platform for controlling/switching the hydration of bolaamphiphile skeletons in water in an effective and simple manner by the virtue of covalent bonding. The adaptive behaviour of the macrocyclic bolaamphiphiles(transformations between C7SeBola and C7SeOBola) in response to redox environment was found to be a decisive factor.

关键词： Macrocycle Crown ether Bola Amphiphiles Selenium

The Reduced space Method for Calculating the Periodic Solution of Nonlinear Systems

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Computer Modeling in Engineering & Sciences 2018年第5期115卷 233-262页

作者： Haitao Liao institute of advanced structure technology Beijing institute of technologyBeijing 100081China

A hybrid method combined the reduced Sequential Quadratic Programming(SQP)method with the harmonic balance method has been developed to analyze the characteristics of mode localization and internal resonance of nonlinear bladed *** the aid of harmonic balance method,the nonlinear equality constraints for the constrained optimization problem are *** reduced SQP method is then utilized to deal with the original constrained optimization *** the null space decomposition technique to the harmonic balance algebraic equations results in the vanishing of the nonlinear equality constraints and a simple optimization problem involving only upper and lower bound constraints on the optimization variables is formed and ***,numerical results are given for several test examples to validity the proposed *** efficiency of the solution method to trace the family of energy dependent nonlinear modes is *** localization nonlinear normal modes of bladed disks related to various types of internal resonances are explored.

关键词： Nonlinear normal modes internal resonances reduced SQP method harmonic balance method

Star Centroid Location Based on Information Entropy and Minimum Energy Difference

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Star Centroid Location Based on Information Entropy and Mini...

新型导航技术及应用研讨会

作者： Feng Liu Tong Sheng Shen Xinxing Ma Naval aeronautical and Astronautical University National Defense Science and Technology information center

Celestial navigation technology has entered a new stage of development with the development of electronic technology and computer technology. Otherwise it has been widely used in satellite, space shuttle, long-range missiles and other spacecraft. Star centroid location for celestial navigation is the key technologies. Due to the strong sky background, near-infrared stellar images which are taken during the day have the low signal noise ratio. First, this paper adopts the method of information entropy to make analysis the stellar images energy distribution. And then we proposed a method for star target centroid located based on multi-step minimum energy difference. This method uses the linear superposition to narrow the centroid area, using the symmetry of the stellar energy distribution to obtain the centroid when the minimum difference appears. We test the modal on natural pictures to verify the accuracy. Experiments show that it has good effect to calculate the centroid with low SNR conditions.

关键词： Celestial navigation Minimum energy difference information entropy Centroid location

Intelligent Maneuver Decision Method of UAV based on Reinforcement Learning and Neural Network

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Intelligent Maneuver Decision Method of UAV based on Reinfor...

第40届中国控制会议

作者： Huan Zhou Senyu Zhang Chu Sun Changjian Ru aeronautical Engineering College Air Force Engineering University 94019 Unit PLA

The efficiency of UAV maneuver decision-making based on the traditional maneuver control quantity is the key to restrict the improvement of UAV autonomous air combat game ability in complex battlefield *** refining pilots’ combat training and air combat thinking experience,the intelligent maneuver decision-making method for UAV autonomous air combat can effectively improve the UAV autonomous air combat *** at the problem of maneuver decision-making in continuous state space,this paper designs an autonomous maneuver decision-making model based on actor critical reinforcement learning theory,adopts NRBF neural network as the value function approximator,the action controller outputs continuous control variables,and introduces Gaussian random action variables to balance the problem of "exploration utilization" in strategy learning A state space adaptive adjustment method based on relative entropy distance is proposed to simplify the network structure and enhance the learning ability of the *** simulation results show that the proposed method has the ability of air combat confrontation,the output control quantity is smooth,and the strategy learning efficiency is higher.

关键词： UAV Intelligent Decision Reinforcement Learning Neural Network and Autonomous Air Combat

Improved SIFT Algorithm Image Matching

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光学应用（中英文版） 2013年第1期2卷 1-7页

作者： Can Ding Chang-wen Qu Jie Gao Department of Electronic and Information Engineering Naval Aeronautical & Astronautical University Yantai 26400 China 92840 Unit Qingdao 266405 China

Weighted Approximation of Kantorovich-Type Operator of Butzer-Hahn

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Journal of Southwest Jiaotong University(English Edition) 2005年第1期13卷 95-102页

作者：田军王绍钦王玉 School of Management Fudan University Shanghai 200433 ChinaDepartment of Commodities and Business TradeZhengzhou Institute of Aeronautical Industrial Management Zhengzhou 450015 China Seventh Faculty People's Liberation Army Foreign Language Institute Luoyang 471003 China School of Adult Education Southwest Jiaotong University Chengdu 610031 China

A kind of Kantorovich-type operator of Butzer-Hahn B*_n(f; x) on the bounded and integrable function space was introduced, and the properties of B*_n(f; x) were studied. Positive theorem, converse theorem, and the ord... 详细信息

关键词： Kantorovich-type operator of Butzer-Hahn Properties of approximation Weighted approximation

High-entropy ceramics:Present status,challenges,and a look forward

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Journal of Advanced Ceramics 2021年第3期10卷 385-441页

作者： Huimin XIANG Yan XING Fu-zhi DAI Hongjie WANG Lei SU Lei MIAO Guojun ZHANG Yiguang WANG Xiwei QI Lei YAO Hailong WANG Biao ZHAO Jianqiang LI Yanchun ZHOU Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China New Energy Technology Engineering Laboratory of Jiangsu Province Nanjing University of Posts and TelecommunicationsNanjing 210023China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Guangxi Key Laboratory of Information Materials Guangxi Collaborative Innovation Center of Structure and Property for New Energy and MaterialSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China institute of Functional Material College of Material Science and EngineeringDonghua UniversityShanghai 201620China institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210China College of Material Science and Engineering Shenzhen UniversityShenzhen 518060China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology CAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal *** in the infant stage,the emerging of this new family of materials has brought new opportunities for material design and property *** from metals,the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon *** from strengthening,hardening,and low thermal conductivity that have already been found in high-entropy alloys,new properties like colossal dielectric constant,super ionic conductivity,severe anisotropic thermal expansion coefficient,strong electromagnetic wave absorption,etc.,have been discovered in *** a response to the rapid development in this nascent field,this article gives a comprehensive review on the structure features,theoretical methods for stability and property prediction,processing routes,novel properties,and prospective applications of *** challenges on processing,characterization,and property predictions are also ***,future directions for new material exploration,novel processing,fundamental understanding,in-depth characterization,and database assessments are given.

关键词： high-entropy ceramics(HECs) processing structure properties applications