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Novel passive localization algorithm based on weighted restricted total least square

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Journal of Systems Engineering and Electronics 2013年第4期24卷 592-599页

作者： Changwen Qu Zheng Xu Changhai Wang department of Electronic and Information Engineering Naval Aeronautical and Astronautical University Science and Technology on avionics Integration Laboratory

A novel multi-observer passive localization algorithm based on the weighted restricted total least square （WRTLS） is proposed to solve the bearings-only localization problem in the presence of observer position errors. Firstly, the unknown matrix perturbation information is utilized to form the WRTLS problem. Then, the corresponding constrained optimization problem is transformed into an unconstrained one, which is a generalized Rayleigh quotient minimization problem. Thus, the solution can be got through the generalized eigenvalue decomposition and requires no initial state guess process. Simulation results indicate that the proposed algorithm can approach the Cramer-Rao lower bound （CRLB）, and the localization solution is asymptotically unbiased.

关键词： passive localization bearing weighted restricted total least square (WRTLS) generalized Rayleigh quotient.

The Negative Thermal Expansion Property of NdMnO_(3) Based on Pores Effect and Phase Transition

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 39-43页

作者：李玉成张扬 ZHANG Muqun DUAN Rong LIU Xiteng department of avionics Engineering Aviation Maintenance NCO Academy of Air Force Engineering UniversityXinyang 464000China

A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were investigated by variable temperature X-ray diffraction(XRD), scanning electron microscope(SEM) and variable temperature Raman spectra. The compound exhibits NTE properties in the orderly O' phase crystal structure. When the temperature is from 293 to 759 K, the ceramic NdMnO_(3) shows negative thermal expansion of-4.7×10^(-6)/K. As temperature increases, the ceramic NdMnO_(3) presents NTE property range from 759 to 1 007 K. The average linear expansion coefficient is-18.88×10^(-6)/K. The physical mechanism of NTE is discussed and clarified through experiments.

关键词： negative thermal expansion NdMnO_(3) pores effect phase transition

Survey and technological analysis of laser and its defense applications

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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

MODIFIED H-R MIXED VARIATIONAL PRINCIPLE FOR MAGNETOELECTROELASTIC BODIES AND STATE-VECTOR EQUATION

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Applied Mathematics and Mechanics(English Edition) 2005年第6期26卷 722-728页

作者：卿光辉邱家俊刘艳红 Aeronautical Mechanics & avionics Engineering College Civil Aviation University of China department of Mechanics and Engineering Measurement School of Mechanical Engineering

Based upon the Hellinger-Reissner (H-R) mixed variational principle for three-dimensional elastic bodies, the modified H-R mixed variational theorem for magnetoelectroelastic bodies was established. The state-vector equation of magnetoelectroelastic plates was derived from the proposed theorem by performing the variational operations. To lay a theoretical basis of the semi-analytical solution applied with the magnetoelectroelastic plates, the state-vector equation for the discrete element in plane was proposed through the use of the proposed principle. Finally, it is pointed out that the modified H-R mixed variational principle for pure elastic, single piezoelectric or single piezomagnetic bodies are the special cases of the present variational theorem.

关键词： magnetoelectroelastic body variational principle laminated plates state-vector equation semi-analytical solution

State-vector equation with damping and vibration analysis of laminates

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Applied Mathematics and Mechanics(English Edition) 2007年第2期28卷 253-259页

作者：卿光辉徐建新邱家俊 Aeronautical Mechanics and avionics Engineering College Civil Aviation University of China department of Mechanics and Engineering Measurement School of Mechanical EngineeringTianjin University

Based on the modified mixed Hellinger-Reissner（H-R） variational principle for elastic bodies with damping, the state-vector equation with parameters is directionally derived from the principle. A new solution for the harmonic vibration of simply supported rectangular laminates with damping is proposed by using the precise integration method and Muller method. The general solutions for the free vibration of underdamping, critical damp and overdamping of composite laminates are given simply in terms of the linear damping vibration theory. The effect of viscous damping force on the vibration of composite laminates is investigated through numerical examples. The state-vector equation theory and its application areas are extended.

关键词： laminted plates damping vibration H-R variational theorem statevector equation

How Properties that Distinguish Solids from Fluids and Constraints of Spherical Geometry Suppress Lower Mantle Convection

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Journal of Earth Science 2018年第1期29卷 1-20页

作者： Anne M. Hofmeister Everett M. Criss department of Earth and Planetary Sciences Washington University St. Louis MO 63130 USA Panasonic avionics Corporation Lake Forest CA 92630 USA

The large magnitude of the dimensionless Rayleigh number （Ra-10^8） for Earth＇s -3 000 km thick mantle is considered evidence of whole mantle convection. However, the current formulation assumes behavior characteristic of gases and liquids and also assumes Cartesian geometry. Issues arising from neglecting physical properties unique to solids and ignoring the spherical shapes for planets include：（1） Planet radius must be incorporated into Ra, in addition to layer thickness, to conserve mass during radial displacements. （2） The vastly different rates for heat and mass diffusion in solids, which result from their decoupled transport mechanisms, promote stability. （3） Unlike liquids, sub- stantial stress is needed to deform solids, which independently promotes stability. （4） High interior compression stabilizes the mantle in additional minor ways. Therefore, representing conditions for convection in solid, self-gravitating spheroids, requires modifying formulae developed for bottom- heated fluids near ambient conditions under an invariant gravitational field. To derive stability criteria appropriate to solid spheres, we use dimensional analysis, and consider the effects of geometry, force competition, and microscopic behavior. We show that internal heating has been improperly ac- counted for in the Ra. We conclude that the lower mantle is stable for two independent reasons： heat diffusion far outpaces mass diffusion （creep） and yield strength of solids at high pressure exceeds the effective deviatoric stress. We discuss the role of partial melt in lubricating plate motion, and explain why the Ra is not applicable to the multi-component upper mantle. When conduction is insufficient to transport heat in the Earth, melt production and ascent are expected, not convection of solid rock.

关键词： plasticity diffusion mantle convection stability criteria dimensional analysis geometry.

Asymptotic Magnitude Bode Plots of Fractional-Order Transfer Functions

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 1019-1026页

作者： Ameya Anil Kesarkar Selvaganesan Narayanasamy IEEE the Space Applications Centre (SAC) Indian Space Research Organization (ISRO)AhmedabadGujaratIndia the department of avionics Indian Institute of Space Science and Technology (IIST)ThiruvananthapuramKeralaIndia

Development of asymptotic magnitude Bode plots for integer-order transfer functions is a well-established topic in the control ***,construction of such plots for the fractional-order transfer functions has not received much attention in the existing *** the present paper,we investigate in this direction and derive the procedures for sketching asymptotic magnitude Bode plots for some of the popular fractional-order controllers such as PI^α,[PI]^α,PD^β,[PD]^β,and PI^αD^β.In addition,we deduce these plots for general fractional commensurate-order transfer functions as *** applications of this work,we illustrate 1)the analysis of the designed fractional-control loop and 2)the identification of fractional-order transfer function from a given plot.

关键词： Asymptotic magnitude Bode commensurateorder fractional-order

Hamiltonian parametric element and semi-analytical solution for smart laminated plates

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Applied Mathematics and Mechanics(English Edition) 2007年第1期28卷 51-58页

作者：卿光辉邱家俊刘艳红 Aeronautical Mechanics and avionics Engineering College Civil Aviation University of China Tianjin 300300 P. R. China department of Mechanics and Engineering Measurement School of Mechanical Engineering Tianjin University Tianjin 300072 P. R. China Aeronautical Mechanics and avionics Engineering College Civil Aviation University of China Tianjin 300300 P. R. China

Based on the Hellinger-Reissner （H-R） mixed variational principle for piezoelectric material, a unified 4-node Hamiltonian isoparametric element of anisotropy piezoelectric material is established. A new semi-analytical solution for the natural vibration of smart laminated plates and the transient response of the laminated cantilever with piezoelectric patch is presented. The major steps of mathematical model are as follows： the piezoelectric layer and host layer of laminated plate are considered as unattached three-dimensional bodies and discretized by the Hamiltonian isoparametric elements. The control equation of whole structure is derived by considering the compatibility of generalized displacements and generalized stresses on the interface between layers. There is no restriction for the side-face geometrical boundaries, the thickness and the number of layers of plate by the use of the present isoparametric element. Present method has wide application area.

关键词： piezoelectric material smart laminated plate vibration analysis Hamilto-nian isoparametric element semi-analytical solution

Hyperspectral anomaly detection:a performance comparison of existing techniques

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International Journal of Digital Earth 2022年第1期15卷 2078-2125页

作者： Noman Raza Shah Abdur Rahman M.Maud Farrukh Aziz Bhatti Muhammad Khizer Ali Khurram Khurshid Moazam Maqsood Muhammad Amin iVISION Lab Electrical Engineering DepartmentInstitute of Space TechnologyIslamabadPakistan AI Enabling Technologies Lab Center of Excellence in Artificial IntelligenceBahria UniversityIslamabadPakistan department of Electrical and Computer Engineering Pak-Austria Fachhochschule:Institute of Applied Sciences and TechnologyHaripurPakistan avionics Engineering department Institute of Space TechnologyIslamabadPakistan

Anomaly detection in Hyperspectral Imagery(HSI)has received considerable attention because of its potential application in several *** anomaly detection algorithms for HSI have been proposed in the literature;however,due to the use of different datasets in previous studies,an extensive performance comparison of these algorithms is *** this paper,an overview of the current state of research in hyperspectral anomaly detection is presented by broadly dividing all the previously proposed algorithms into eight different *** addition,this paper presents the most comprehensive comparative analysis to-date in hyperspectral anomaly detection by evaluating 22 algorithms on 17 different publicly available *** indicate that attribute and edge-preserving filtering-based detection(AED),local summation anomaly detection based on collaborative representation and inverse distance weight(LSAD-CR-IDW)and local summation unsupervised nearest regularized subspace with an outlier removal anomaly detector(LSUNRSORAD)perform better as indicated by the mean and median values of area under the receiver operating characteristic(ROC)***,this paper studies the effect of various dimensionality reduction techniques on anomaly *** indicate that reducing the number of components to around 20 improves the performance;however,any further decrease deteriorates the performance.

关键词： Anomaly detection algorithms hyperspectral imagery deep learning dimensionality reduction