INERTIAL MANIFOLDS FOR NONAUTONOMOUS SEMILINEAR PARABOLIC PARTIAL DIFFERENTIAL EQUATIONS WITH TIME DELAYS

The present paper deals with the long-time behavior of a class of nonautonomous retarded semilinear parabolic differential equations. When the time delays are small enough and the spectral gap conditions hold, the inertial manifolds of the nonautonomous retard parabolic equations are constructed by using the Lyapunov-Perron method.     

DISSIPATIVE SCHEMES WITH PROPERTY OF INHERITING HOMOCLINIC ORBITS FOR 2N-DIMENSIONAL HAMILTONIAN SYSTEMS

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｉｓｐａｐｅｒｉｓｄｅｖｏｔｅｄｔｏｓｔｕｄｙｗｈａｔｋｉｎｄｏｆｄｉｓｃｒｅｔｅｓｃｈｅｍｅｓｏｆｔｈｅｆｏｌｌｏｗｉｎｇ 2ｎ ｄｉｍｅｎ ｓｉｏｎａｌＨａｍｉｌｔｏｎｉａｎｓｙｓｔｅｍｓｗｉｔｈｐａｒａｍｅｔｅｒｉｎｎｏｒｍａｌｆｏｒｍ ｕ=Ｊ2ｎ Ｈ ｕＴ,　　Ｈ =Ｈ(ｕ ,λ) ,(1 )ｗｈｅｒｅｕ∈Ｒ2ｎ,λ∈Ｒ ,Ｈ∈Ｃｋ+1(Ｒ2ｎ×Ｒ ,Ｒ) ,ｋ≥ 6,ａｎｄＪ2ｎ =0Ｉｎ-Ｉｎ 0 ,Ｉｎ:ｕｎｉｔｍａｔｒｉｘｏｆｏｒｄｅｒｎｈａｓｔｈｅｐｒｏｐｅｒｔｙｏｆｉｎｈｅｒｉｔｉｎｇｈｏｍ…     

改进形态学相关算法以识别高相似度灰度图像

从形态学角度定义了灰度联合图像相似度，提出两种基于位表示法形态学相关算法的改进算法，通过提取位表示法的图像片边缘特征或二元化位表示法的图像片功率谱，以提高位表示法形态学相关算法对高相似度灰度图像的识别能力。     

Recursive method for ARMA model estimation (II)

In this paper a new recursive method for ARMA model estimation is given. Same as in [1], the order's estimator is strongly consistent, and the pearameter's estimaters defer to CLT and LIL under a natural condition. Compared with the previous methods suggested by Hannan & Kavalieris (1984), Wang Shouren & Chen Zhaoguo (1985) and Franke (1985), this method has some advantages: the amount of calculat on work is smaller, the minimum-phase property of coefficient estimators can be guaranteed, the BAN estimators for MA or AR model can be obtained directly, and the simulation shows that this method is more accurate in estimating the order and parameters.     

Demonstration of Soliton Solutions of DNLS Equation by Liouville Theorem

In the inverse scattering transform (IST), the reflectionless Jost solutions are combined by their analytic properties in the complex spectrum parameter plane, and then can be shown to satisfy the two Lax equations indeed by Liouville theorem. So the corresponding soliton solutions certainly satisfy the nonlinear equation by compatibility condition. Especially the multi-soliton solutions of DNLS equation can be demonstrated in this way. PACS Numbers: 05.45.Yv, 02.30.-f, 11.10.Ef     

泛函梯度数值计算的一种新方法—正交试验法

本文研究并揭示了L_(2~a)(2~(2~a-1))型正交表行(列)间的递推规律,提出了一种泛函梯度数值计算的新方法——正交试验法,该方法在计算速度和精度上优于直接梯度法;在通用性及节省内存方面优于伴随算子法。     

~（23）Na~（39）K分子D~1∏→X~1∑~＋激光感生荧光光谱及强度研究

实验获得了Ａｒ＋激光５１４．５ｎｍ线诱导２３Ｎａ３９Ｋ分子产生的Ｄ１∏→Ｘ１∑＋跃迁荧光谱．通过测量激光感生荧光光谱强度随泵浦功率、热管炉温度及缓冲气压变化规律，详细研究了其跃迁机制．用最小二乘法拟合获得２３Ｎａ３９Ｋ分于Ｘ１∑＋态振动常数．理论计算了各跃迁谱支波长值及Ｆｒａｎｃｋ－Ｃｏｎｄｏｎ因子和光谱强度值，与实验观测值符合得相当好，充分表明本文对激光感生荧光光谱的归属以及对各支谱线振、转量子数的赋值是合理的．     

用峰面积判据改善Delsuc法预测的谱

基于Prony算法的Delsuc谱预测是目前NMR LPSVD(Linear Prediction SingularValue Decomposition)法中比较实用的方法。但在高噪声的条件下,时有失峰和假峰出现且要事先知道谱的峰数。本文通过跟踪迭代过程发现Delsuc法的判别因子r_(mis) 很难选定。如果它太小会失峰,而过大又会出现假峰。同时,由于噪声的影响,弱信号的采样点之间的相关性比强信号小,从而在迭代过程中会增加数值不稳定性。文中引入峰面积判据来改善Delsuc法,经模拟与实验均证明结果有效。     

偶氮苯衍生物三阶非线性的四波混频研究

用皮秒Ｎｄ：ＹＡＧ激光器的倍频光（５３２ｎｍ）对具有离域π－共轭电子云结构的偶氮苯类样品材料作简并四波混频补给，测得三阶非线性电极化率ｘ＾（３）和它们的时间响应分别为１０＾－９ｅｓｕ和２０ｐｓ，并对影响ｘ＾（３）的瞬时光栅作用和ｘ＾（３）的响应时间人了讨论。     

Multi-cracks problem for piezoelectric materials strip subjected to dynamic loading

This paper analyses and models the dynamic interaction among permeable multi-cracks in a piezoelectric strip under anti-plane shear waves by the Schmidt method. The Fourier transform is applied and then two pairs of triple integral equations can be solved using the Schmidt method. The results show that the stress and the electric displacement intensity factors of cracks depend on not only the crack length and the piezoelectric coefficient, but also the thickness of the piezoelectric strip, the distance between multi-cracks and the frequency of incident wave.