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On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

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Communications in Theoretical Physics 2007年第7期48卷 37-42页

作者： ZHAO Shu-Hong LIANG Li-Fuoi School of Civil engineering,harbin engineering university,harbin 150001,China2 engineering College,Northeast Agricultural university,harbin 150030,China School of Civil engineering Harbin Engineering University engineering College Northeast Agricultural University

In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived ***,an example is given to illustrate the application of the result.

关键词： form invariance Lie symmetry conserved quantity generalized classical mechanics Lagrange’s equation

New method for passive radar seeker to antagonize non-coherent radar decoy

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Journal of Systems engineering and Electronics 2010年第3期21卷 397-403页

作者： Weijian Si,Xicai Si,and Zhiyu Qu College of Information and Communication engineering,harbin engineering university,harbin 150001,P.R.China College of Information and Communication engineering Harbin Engineering University Harbin 150001 P. R. China

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（PRS） to antagonize non-coherent radar *** the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is *** this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated *** this new method,PRS can distinguish radar and non-coherent decoy with good *** the simulation result and the experimental data confirm the performance of the method.

关键词： radar countermeasures passive radar seeker(PRS) non-coherent decoy direction of arrival(DOA) estimation.

STRESS CONCENTRATIONS IN CYLINDRICAL SHELLS WITH LARGE OPENINGS

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Acta Mechanica Solida Sinica 1997年第3期10卷 220-234页

作者： Liu Diankui Song Tianshu, harbin engineering university, harbin 150001, China harbin engineering university Harbin 150001 China

Based on Donnell's shallow shell equation, a new method is given in this paper to analyze theoretical solutions of stress concentrations about cylindrical shells with large openings. With the method of complex variable function, a series' of conformal mapping functions are obtained from different cutouts' boundary curves in the developed plane of a cylindrical shell to the unit circle. And, the general expressions for the equations of a cylindrical shell, including the solutions of stress concentrations meeting the boundary conditions of the large openings' edges, are given in the mapping plane. Furthermore, by applying the orthogonal function expansion technique, the problem can be summarized into the solution of infinite algebraic equation series. Finally, numerical results are obtained for stress concentration factors at the cutout's edge with various opening's ratios and different loading conditions. This new method, at the same time, gives a possibility to the research of cylindrical shells with large non-circular openings or with nozzles.

关键词： cylindrical shell with large opening theoretical solution for single circular cutout conformal mapping and complex variable method

Interference Patterns of three-fiber Mach-Zehnder Interferometer and its Numerical Simulation

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Chinese Journal of Lasers 1998年第4期B7卷 89-97页

作者： YUAN Libo (Department of Physics, harbin engineering university, harbin 150001, China) harbin engineering Univ Harbin China

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１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｆｉｂｅｒｏｐｔｉｃＭａｃｈＺｅｈｎｄｅｒｉｎｔｅｒｆｅｒｏｍｅｔｅｒｉｓａｗｅｌｅｓｔａｂｌｉｓｈｅｄａｎｄｗｉｄｅｌｙｕｓｅｄｄｅｖｉｃｅ．Ｔｈｅｅｘｐｅｒｉｍｅｎｔａｌｂａｃｋｇｒｏｕｄｏｆｆｉｂｅｒｏｐｔｉｃ...

关键词： optical interfrence fiber Mach Zehnder interferometer interfence pattern

Dynamics Model of Carrier-based Aircraft Landing Gears Landed on Dynamic Deck

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Chinese Journal of Aeronautics 2009年第4期22卷 371-379页

作者： Zhang Wen,Zhang Zhi,Zhu Qidan,Xu Shiyue Department of Automation,harbin engineering university,harbin 150001,China Department of Automation Harbin Engineering University Harbin 150001 China

In order to study the carrier-based aircraft landing laws landed on the carrier, the dynamics model of carrier-based aircraft landing gears landed on dynamic deck is built. In this model, the interactions of the carrier-based aircraft landing attitude and the damping force acting on landing gears are considered, and the influence of dynamic deck is introduced into the model through the deck normal vectors. The wheel-deck coordinate system is put forward to solve the complex simulation problem of force-onwheel which comes from the dynamic deck. At last, by simulation, it is demonstrated that the model can be applied to landing attitude when the carrier-based aircraft is landing on the dynamic deck, it is also proved that the model is comprehensive and suitable for any abnormal landing situation.

关键词： carrier-based aircraft landing gear deck wheel-deck coordinate system landing

AN ORDINARY DIFFERENTIAL EQUATION FOR THE 2D TRANSIENT FREE-SURFACE GREEN FUNCTIONS

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Journal of Hydrodynamics 2002年第2期14卷 24-28页

作者： Duan Wen-yang College of Shipbuilding engineering, harbin engineering university, harbin 150001, ChinaPrice W.G. School of engineering Sciences, Ship Science, university of Southampton, UK Coll. of Shipbuilding Eng. Harbin Eng. Univ. Harbin 150001 China Sch. of Eng. Sci. Ship Sci. Univ. of Southampton Southampton United Kingdom

Based on the Laplace transform an ordinary differential equation for the two-dimensional time-domain free-surface Green function in ship hydrodynamics is presented. The results for 2D Green function and its horizontal derivative are fifth-order ODEs and the vertical derivative satisfies a fourth-order ODE. All of these results may be used to accelerate the numerical computations for the time-domain BEM in marine hydrodynamics.

关键词： ship hydrodynamics time-domain Green function Laplace transform

Performance tests of multi-metal zincate solutions with zinc sulfate and zinc oxide

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Rare Metals 2007年第S1期26卷 99-104页

作者： HUANG Xiaomei,and ZHANG Milin College of Materials Science and Chemical engineering,harbin engineering university,harbin 150001,China harbin Engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron *** was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc ***,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was ***,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the *** results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating *** zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.

关键词： Al-Si alloy multi-metal zincating solution adhesion

A circular zone partition method for identifying Duffing oscillator state transition and its application to BPSK signal demodulation

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Science China(Information Sciences) 2011年第6期54卷 1274-1282页

作者： FU YongQing 1 , WU DongMei 1 , ZHANG Lin 2 & LI XingYuan 1 1 College of Information and Communication engineering, harbin engineering university, harbin 150001, China 2 College of Underwater Acoustic engineering, harbin engineering university, harbin 150001, China College of Information and Communication engineering Harbin Engineering University College of Underwater Acoustic engineering Harbin Engineering University

When a Duffing oscillator is applied to signal detection, identifying its state transition is indispensable. Due to lack of an effective method for automatically distinguishing the state transition, phase analysis is extensively used. However, it needs ocular estimation to identify phase pattern corresponding to transition of Duffing oscillator. Hence it is not fit for communication signal demodulation. To solve the problem, this paper proposes a method, called circular zone partition (CZP), for partitioning trajectory on the phase plane of Duffing oscillator. First, a computing model for Duffing oscillator is described. Then, the fundamental principle and algorithm for the CZP method are discussed. Meanwhile the equation of a circular zone divider and its realization are presented. Thus, by way of the divider, the two-dimensional phase trajectory pattern of Duffing oscillator driven by an external signal can be transformed into the one-dimensional time signal, whose envelop after being filtered is able to indicate the state transition, i.e. the presence or the absence of external signal. Finally, to verify the effect of the CZP method on binary phase shifted keying (BPSK) signal demodulation, two examples are presented and simulation results show that this CZP method is accurate and valid for BPSK signal demodulation.

关键词： chaos nonlinear oscillators signal detection digital communication receivers

Method for determining number of coherent signals in the presence of colored noise

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Journal of Systems engineering and Electronics 2010年第1期21卷 27-30页

作者： Jiaqi Zhen, Xicai Si, and Lutao Liu College of Information & Communication engineering, harbin engineering university, harbin 150001, P. R. China College of Information & Communication engineering Harbin Engineering University Harbin 150001 P. R. China

The approach of estimating the number of signals based on information theoretic criteria has good performance in the assumption of white noise, but it always leads to false estimation of the coherent sources in colored noise. An approach combining the combined information theoretic criteria and eigen- value correction, is presented to determine number of signals. The method uses maximum likelihood （ML） and information theoretic criteria to estimate coherent signals alternately, then eliminate the inequality of the eigenvalues caused by colored noise by correcting the noise eigenvalues. The computer simulation results prove the effective performance of the method.

关键词： determining the number of signals coherent signals colored noise information theoretic criteria.