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Survey and technological analysis of laser and its defense applications

Defence Technology（防务技术） 2021年第2期17卷 583-592页

作者： Syed Affan Ahmed Mujahid Mohsin Syed Muhammad Zubair Ali Department of Avionics Engineering-college of aeronautical Engineering(CAE) National University of Sciences and Technology(NUST)RisalpurKPKPakistan

The laser technology has made remarkable progress over the past couple of *** is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military *** to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive *** modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground ***,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial ***,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical ***,the developments in space sciences and laser technology have given synergistic potential outcomes to use laser systems in space *** paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in ***,a detailed analysis has been done on recent advancements of the laser technology for target indicators and *** also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and advancements in the domain of high energy directed laser weapons that have revolutionized the evolving military *** offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains.

关键词： Laser systems Laser military applications Directed energy weapons Non-lethal weapons Laser military projects Survey Taxonomy

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THE USAGE OF HERMITE POLYNOMIAL IN THE CALCULATION OF STRUCTUBAL DYNAMIC RESPONSES

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Applied Mathematics and Mechanics(English Edition) 1988年第3期9卷 241-251页

作者：张益松徐尹格高德平 Najing aeronautical Institute Nanjing Beijing Jiaotong Manager college Beijing Nanjing aeronautical Institute Nanjing

This paper employs the best approximation of part series sum of normal polynomials, and proposes a new method with the Fourier-Hermite polynomial expansion expressing structural dynamic responses. Analytic expressions of displacement and velocity responses of vibrational systems are established in this paper, and stability condition of the step-by-step algorithm is discussed. Finally, a computational example is demonstrated, and the precision of its results is compared with conventional methods.

关键词： THE USAGE OF HERMITE POLYNOMIAL IN THE CALCULATION OF STRUCTUBAL DYNAMIC RESPONSES exp In Zhang length PI CI

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Nonconforming stabilized combined finite element method for Reissner-Mindlin plate

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Applied Mathematics and Mechanics(English Edition) 2009年第2期30卷 197-207页

作者：冯民富杨艳周天孝 college of Mathematics Sichuan University School of Sciences Southwest Petroleum University Institute of aeronautical Computing Techniques

Based on combination of two variational principles, a nonconforming stabilized finite element method is presented for the Reissner-Mindlin plates. The method is convergent when the finite element space is energy-compatible. Error estimates are derived. In particular, three finite element spaces are applied in the computation. Numerical results show that the method is insensitive to the mesh distortion and has better performence than the MITC4 and DKQ methods. With properly chosen parameters, high accuracy can be obtained at coarse meshes.

关键词： Reissner-Mindlin plate energy-compatibility combined FEM nonconforming finite element

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Elastic Collisions Between two Ground-State P and D Atoms at Low and Ultralow Temperatures

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Communications in Theoretical Physics 2010年第2期53卷 331-338页

作者：施德恒张金平孙金锋马恒刘玉芳朱遵略 Department of Foundation The First Aeronautical College of Air Force college of Physics & Electronic Engineering Xinyang Normal University college of Physics & Information Engineering Henan Normal University

The PD（X^3∑^-） interaction potential is constructed using the CCSD（T） theory and the basis set, augcc-pV5Z. Using this potential, the spectroscopic parameters are accurately determined. The present Do, De, Re, ωe, ωeχe, αe, and Be are of 3.056 99 eV, 3.161 75 eV, 0.142 39 nm, 1701.558 cm^-1, 23.6583 cm^-1, 0.085 99 cm^-1, and 4.3963 cm^-1, respectively, which almost perfectly conform with the measurements. A total of 26 vibrational states is predicted when J = 0 by solving the radial Sehrodinger equation of nuclear motion. The complete vibrational levels, classical turning points, initial rotation and centrifugal distortion constants when J = 0 are reported for the first time, which favorably agree with the experiments. The total and various partial-wave cross sections are calculated for the elastic impact between two ground-state P and D atoms at 1.0 × 10^-12 - 1.0 × 10^-4 a.u. when they approach each other along the PD（X^3∑^-） potential. No shape resonances exist in the total elastic cross sections, though the peaks can be found for each partial wave until l=6. The shape of the total elastic cross sections is dominated by the s partial wave at very low temperatures. Due to the weakness of the shape resonances of each partial wave, they are all passed into oblivion by the strong total elastic cross sections.

关键词： elastic scattering total cross section shape resonance molecular constant

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Adaptive fuzzy tracking control for a class of uncertain MIMO nonlinear systems using disturbance observer

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Science China(Information Sciences) 2014年第1期57卷 246-258页

作者： CHEN Mou CHEN WenHua WU QinXian college of Automation Engineering Nanjing University of Aeronautics and Astronautics Department of aeronautical and Automotive Engineering Loughborough University Loughborough

In this paper,the adaptive fuzzy tracking control is proposed for a class of multi-input and multioutput(MIMO)nonlinear systems in the presence of system uncertainties,unknown non-symmetric input saturation and external *** logic systems(FLS)are used to approximate the system uncertainty of MIMO nonlinear ***,the compound disturbance containing the approximation error and the timevarying external disturbance that cannot be directly measured are estimated via a disturbance *** appropriately choosing the gain matrix,the disturbance observer can approximate the compound disturbance well and the estimate error converges to a compact *** control strategy is further extended to develop adaptive fuzzy tracking control for MIMO nonlinear systems by coping with practical issues in engineering applications,in particular unknown non-symmetric input saturation and control *** this setting,the disturbance observer technique is combined with the FLS approximation technique to compensate for the efects of unknown input saturation and control *** approach based analysis shows that semi-global uniform boundedness of the closed-loop signals is guaranteed under the proposed tracking control *** simulation results are presented to illustrate the efectiveness of the proposed tracking control schemes.

关键词： MIMO nonlinear system input saturation disturbance observer fuzzy logic systems tracking control

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Real-Time Rendering of Dynamic Clouds Using Multi-Resolution Adaptive Grids

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第4期32卷 428-437页

作者：范晓磊张立民钟兆根 Department of Electronics and Information Engineering Naval Aeronautical and Astronautical University Noncommissioned Officers Vocational and Technical Education college the Second Artillery Engineering University Department of Scientific Research Naval Aeronautical and Astronautical University

The multi-resolution adaptive grids method is proposed to solve the problems of inefficiency in the previous grid-based methods,and it can be used in clouds simulation as well as the interactive simulation between objects and *** bounding box(OBB)hierarchical trees of objects are established,and the resolutions of global and local grids can be selected *** motion equations of fluid dynamics are *** difference is applied to ensure the stability of the simulation process during the discrete process of partial differential *** solve the speed problem of existed phase functions,the improved phase function is applied to the illumination calculation of *** results show that the proposed methods can promote the simulation efficiency and meet the need for the simulation of large-scale clouds ***-time rendering of clouds and the interaction between clouds and objects have been realized without preprocessing stage.

关键词： real-time rendering multi-resolution adaptive grids clouds simulation phase function

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Mathematical modeling and analysis of gas torque in twin-rotor piston engine

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Journal of Central South University 2013年第12期20卷 3536-3544页

作者：邓豪潘存云徐小军张湘 college of Mechatronic Engineering and Automation National University of Defense Technology Naval aeronautical Engineering Institute Qingdao Branch

The gas torque in a twin-rotor piston engine(TRPE) was modeled using adiabatic approximation with instantaneous combustion. The first prototype of TRPE was manufactured. This prototype is intended for high power density engines and can produce 36 power strokes per shaft revolution. Compared with the conventional engines, the vector sum of combustion gas forces acting on each rotor piston in TRPE is a pure torque, and the combustion gas rotates the rotors while compresses the gas in the compression chamber at the same time. Mathematical modeling of gas force transmission was built. Expression for gas torque on each rotor was derived. Different variation patterns of the volume change of working chamber were introduced. The analytical and numerical results is presented to demonstrate the main characteristics of gas torque. The results show that the value of gas torque in TRPE falls to be less than zero before the combustion phase is finished; the time for one stroke is 30° in terms of the rotating angle of the output shaft; gas torque in one complete revolution of the output shaft has a period which is equal to 60° and it is necessary to put off the moment when gas torque becomes zero in order to export the maximum energy.

关键词： rotor piston engine gas torque power density adiabatic process

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Effects of the Next Nearest Neighbor Hopping on Superconductivity and Antiferromagnetism of Gossamer Superconductivity

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Communications in Theoretical Physics 2012年第4期57卷 727-730页

作者：刘芬芬张勇袁峰夏临华 Physics and Chemistry Experiment Center Naval Aeronautical and Astronautical University college of Physics Science Qingdao University

The two dimensions hole-doped t-t '-J-U model was studied based on the Gutzwiller approach and the renormalized mean-field *** phase diagrams of gossamer superconductors and the effects of the next-nearestneighbor hopping(t ') on superconductivity and antiferromagnetism based on the t-t '-J-U model were *** results show that the qualitative feature of the phase diagrams in the t-t '-J-U model is the same as in the case of the t-J-U *** antiferromagnetic order coexists with the d-wave superconductivity(dSC) in the underdoped region below the doping δ≈ 0.1 and is enhanced by the t '.The dSC order is slightly suppressed by t ' in the underdoped region and greatly enhanced in the overdoped *** dSC order is pushed to a larger doping region and the coexistence region of the AF and dSC extends to higher doping.

关键词： gossamer superconductivity next-nearest-neighbor hopping antiferromagnetism d-wave superconductivity

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Microstructure inheritance of matrixes of SiC_(f)/Ti6242 composites from precursor wire coatings byα+βphase field consolidation

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Rare Metals 2021年第12期40卷 3676-3684页

作者： Wang-Teng-Fei Fang Xu Huang Hu Li Min-Juan Wan Mao Wen Hao Huang AECC Beijing Institute of aeronautical Materials Beijing 100095China college of Materials Science and Engineering Jilin UniversityChangchun 130012China

SiC_(f)/Ti composite owns the attractive advantages of lightweight and excellent high-temperature performance,which make it have great significance to the development of aerospace ***,the complicated fabrication route and novel architecture of SiC_(f)/Ti composite bring about more difficulties for controlling its *** this work,the method of regulating the structure and performance of the composite matrix by adjusting the characteristics of the precursor wire was *** physical vapor deposition(PVD)method was applied to fabricate precursor ***6242 coatings with bamboo leaf-shaped grains and chrysanthemumshaped grains were deposited on SiC fibers by changing the PVD *** is found that the original structure of the Ti6242 coating of precursor wire has significant impact on the microstructure of the composite matrix after hot isostatic pressing(HIP).The matrix transformed from the Ti6242 coating with bamboo leaf-shaped grains exhibits equiaxed grain *** the other matrix has a columnar crystal structure,and the inside of the columnar crystal inherits the original chrysanthemum-shaped *** columnar crystal matrix has lower hardness and modulus than the equiaxed grain matrix.

关键词： SiC_(f)/Ti composite physical vapor deposition(PVD) Ti6242 coating HIP consolidation Matrix

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Applications of modularized circuit designs in a new hyper-chaotic system circuit implementation

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Chinese Physics B 2015年第2期24卷 78-86页

作者：王蕊孙辉王杰智王鲁王晏超 Tianjin Key Laboratory for Civil Aircraft Airworthiness and Maintenance Department of Electrical EngineeringCollege of Aeronautical AutomationCivil Aviation University of China Department of Electrical Engineering College of Aeronautical AutomationCivil Aviation University of China college of Science Civil Aviation University of China Shandong GUOQIANG Hardware Technology Co. Ltd China Eastern Airlines Corporation Limited

Modularized circuit designs for chaotic systems are introduced in this ***,a typical improved modularized design strategy is proposed and applied to a new hyper-chaotic system circuit *** this paper,the detailed design procedures are *** simulations and physical experiments are conducted,and the simulation results are compared with Matlab simulation results for different system parameter *** results are consistent with each other and they verify the existence of the hyper-chaotic attractor for this new hyper-chaotic system.

关键词： modularized circuit design hyper-chaotic systems Multisim uniform compression transformation

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