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GLOBAL CONVERGENCE AND IMPLEMENTATION OF NGTN METHOD FOR SOLVING LARGE-SCALE SMARSE NONLINEAR PROGRAMMING PROBLEMS

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Journal of Computational Mathematics 2001年第4期19卷 337-346页

作者： Qin Ni (Department of Mathematics, nanjing university of aeronautics and astronautics, nanjing 210016, China) 南京航空航天大学江苏南京 210016

An NGTN method was proposed for solving large-scale sparse nonlinear programming (NLP) problems. This is a hybrid method of a truncated Newton direction and a modified negative gradient direction, which is suitable for handling sparse data structure and pos sesses Q-quadratic convergence rate. The global convergence of this new method is proved, the convergence rate is further analysed, and the detailed implementation is discussed in this paper. Some numerical tests for solving truss optimization and large sparse problems are reported. The theoretical and numerical results show that the new method is efficient for solving large-scale sparse NLP problems.

关键词： Nonlinear programming Large-scale problem Sparse.

HIGH RESOLUTION SCB SCHEME FOR HYPERBOLIC SYSTEMS OF 2-D CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第2期16卷 179-192页

作者： Ning Zhao (Department of Aerodynamics, nanjing university of aeronautics and astronautics, nanjing 210016, China) nanjing Univ Aeronaut & Astronaut Dept Aerodynam Nanjing 210016 Peoples R China

In this paper, a new class of high resolution schemes satisfying the 'condition A' (SCA) and the 'condition B' (SCB) for hyperbolic systems of conservation laws in one and two dimensions are constructed. Moreover, the results of the numerical experiments by using these schemes are given for the system of Euler equations in one and two dimensions.

关键词： SCB scheme hyperbolic system conservation law

A NEW CLASS OF UNIFORMLY SECOND ORDERACCURATE DIFFRENCE SCHEMES FOR 2D SCALAR CONSERVATION LAWS

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Journal of Computational Mathematics 1997年第4期15卷 311-318页

作者： Juan Cheng(Department of Aerodynamics, nanjing university of aeronautics & astronautics,nanjing, China)Jia-zun Dai (Department of Mathematics, Physics and Mechanics, nanjing university of aeronautics & astronautics, nanjing, China) 南京航空航天大学空气动力学系江苏南京南京航空航天大学数学系江苏南京

In this paper, concerned with the Cauchy problem for 2D nonlinear hyperbolic conservation laws,we construct a class of uniformly second order accurate finite difference schemes, which are based on the E-schemes. By applying the conver gence theorem of Coquel-Le Floch [1], the family of approximate solutions defined by the scheme is proven to converge to the unique entropy weak L∞-solution. Furthermore, some numerical experiments on the Cauchy problem for the advection equation and the Riemann problem for the 2D Burgers equation are given and the relatively satisfied result is obtained.

关键词： Math A NEW CLASS OF UNIFORMLY SECOND ORDERACCURATE DIFFRENCE SCHEMES FOR 2D SCALAR CONSERVATION LAWS high Ph

Statistic Characteristics of Logistic Iteration and its Application inGenerating Even Distributed Random Numbers

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Communications in Nonlinear Science and Numerical Simulation 1998年第2期3卷 3-5页

作者： Nailong GUO (Department of Aerodynamics, nanjing university of aeronautics and astronautics, nanjing 210016, China) Department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

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ＩｎｔｒｏｄｕｃｔｉｏｎＬｏｇｉｓｔｉｃｉｔｅｒａｔｉｏｎｐｒｏｖｉｄｅｓａｓｉｍｐｌｅｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｔｏｅｘｈｉｂｉｔｃｈａｏｔｉｃｂｅｈａｖｉｏｒａｎｄｈａｓｂｅｅｎｒｅｓｅａｒｃｈｅｄｂｙａｌｏｔｏｆｒｅｓｅａｒｃｈｅｒｓ［...

关键词： Logistic iteration even distributed random numbers statistic characteristics

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang College of Information Science and Technology,nanjing university of aeronautics and astronautics,nanjing 210016,China [a]College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2D fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2D FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform

Study on the Compatibility of SMA and Composite Materials by Holographic Interferometry

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Chinese Journal of Lasers 2000年第6期9卷 66-71页

作者： ZHAO Zhimin (Applied Optics Research Section, nanjing university of aeronautics & astronautics, nanjing 210016, China) Applied Opt. Res. Section Nanjing Univ. of Aeron. and Astron. Nanjing 210016 China

With the help of holographic interferometry a study is conducted on the compatibility of SMA (shape memory alloy) and epoxy resin composite material. The paper gives experiment results and analysis which show that after coupling SMA with the composite material, the flexural rigidity of composite material is somewhat reinforced. Under certain conditions, SMA and the epoxy resin composite material are compatible.

关键词： SMA composite material compatibili?

Three vortex motion in the slightly viscous flow

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 735-744页

作者： ZHU Hao & CHENG KeMing College of Aerospace Engineering, nanjing university of aeronautics and astronautics, nanjing 210016, China 1. College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The dynamics of three vortices moving in an ideal fluid in a plane can be expressed in Hamiltonian form. However, when viscosity can not be ignored, the system of point vortices has not this delicious structure. This investigation focuses on the viscosity effect on the motion of three vortices. Since the viscous diffusion of vortices is simulated by Brownian motion, the equations of intervortical distances are obtained by Ito formula. These equations show that there exist two viscosity effects on intervortical distances: stable expansion and random impulse. Furthermore, via employing the asymptotic solution to these equations, these two viscous effects have been shown to destroy the self-similar process of collapse and make it into a new configuration, which is similar to the near collapse in the ideal case.

关键词： point vortex slightly viscous flow Fokker-Planck equation collapse Ito formula

Global 4-D trajectory optimization for spacecraft

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Science China(Technological Sciences) 2010年第8期53卷 2097-2101页

作者： NAN Ying ,HUANG GuoQiang,LU YuPing&GONG Ping School of astronautics,nanjing university of aeronautics and astronautics,nanjing 210016,China 1. School of astronautics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Global 4-D trajectory(x,y,z,t)is optimized for a spacecraft,which is launched from the Earth to fly around the Sun,just as star-drift of 1437 asteroids in the solar *** spacecraft trajectory is controlled by low *** performance index of optimal trajectory is to maximize the rendezvous times with the intermediate asteroids,and also maximize the final *** paper provides a combined algorithm of global 4-D trajectory *** algorithm is composed of dynamic programming and two-point-boundary algorithm based on optimal control *** best 4-D trajectory is obtained:the spacecraft flies passing 55 asteroids,and rendezvous with(following or passing again)asteroids for 454 days,and finally rendezvous with the asteroid 2005SN25 on the day 60521(MJD),the final mass of the spacecraft is 836.53 kg.

关键词： spacecraft 4-D trajectory global optimization flight numerical simulation

Inner Attitude Integration Algorithm Based on Fault Detection for Strapdown Inertial Attitude and Heading Reference System

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Chinese Journal of aeronautics 2010年第1期23卷 68-74页

作者： Liu Jianye,Zhu Yanhua,Lai Jizhou,Yu Yongjun Navigation Research Center,nanjing university of aeronautics and astronautics,nanjing 210016,China [a] Navigation Research Center Nanjing University of Aeronautics astronautics Nanjing 210016 China

This article proposes a new inner attitude integration algorithm to improve attitude accuracy of the strapdown inertial attitude and heading reference system （SIAHRS） , which, by means of a Kalman filter, integrates the calculated attitude from the accelerometers in inertial measuring unit （IMU） , called damping attitudes, with those from the conventional IMU. As vehicle＇ s acceleration could produce damping attitude errors, the horizontal outputs from accelerometers are firstly used to judge the vehicle＇ s motion so as to determine whether the damping attitudes could be reasonably applied. This article also analyzes the limitation of this approach. Furthermore, it suggests a residual chi-square test to judge the validity of damping attitude measurement in real time, and accordingly puts forward proper information fusion strategy. Finally,the effectiveness of the proposed algorithm is proved through the experiments on a real system in dynamic and static states.

关键词： navigation strapdown inertial attitude and heading reference system inner attitude integration algorithm internal damping Kalman filter residual chi-square test