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We investigate phenomenologically effects of the flavor-dependent quarkonia annihilation on the meson-meson mixing, and find that corrections due to the flavor-dependent quarknoia annihilation can be described by the constituent quark masses in the mixing model which holds for all the meson nonet. We also study the relation between Regge trajectory and meson spectrum, and therefore concluded that the quasi-linear Regge trajectory with the requirements of additivity of intercepts and inverse slopes can describe the meson spectroscopy with good accuracy, and it also holds for the radial excited mesons except for the bbbar mesons.

我们唯象地研究了味道有关的夸克偶素湮灭效应对混合的影响，发现味道有关的夸克偶素间的湮灭引起的修正可以通过组分夸克的质量来描述，考虑这种修正的混合模型可以用于所有的介子九重态；我们也研究了Regge轨迹和介子质量间关系，发现满足截距相加及斜率倒数相加的准线性Regge轨迹可以很好地描述介子的质量，除bbbar外，线性Regge轨迹也可以很好地描述介子激发态的质量；最后，我们借助于赝标介子和标量介子，讨论多个共振态的混合及衰变。

Secondly two different clutter suppression methods are proposed according to the clutter characteristic of airborne radar with cylindrical array antennas, which can resolve the problem of clutter spectrum's nonhomogeneity at range.

然后根据圆柱型阵机载雷达杂波分布特点提出了两种不同的杂波抑制方法，它们能够很好地解决圆柱型阵机载雷达杂波距离向分布非均匀的问题。

In this paper, firstly the differences between cylindrical array and uniform planar array are discussed in terms of eigenvalue distribution of the clutter covariance matrix and clutter distribution at range, and the conclusion of space-time clutter spectrum's nonhomogeneity at range for airborne radar with cylindrical array antennas is gained.

该文首先从圆柱型阵机载雷达杂波协方差矩阵特征值分布和杂波功率谱距离向分布两个方面分析了圆柱型阵列与均匀平面阵列之间的区别，得到杂波功率谱随距离变化的结论。

In chapter 7, the 2D-distribution of the clutter spectrum in non-sidelooking phased array airborne radar varies with cell range (this can be often called as clutter range dependence), which this kind of nonhomogeneity resulted by range dependence is more serious especially in short range.

第六章提出了一种基于最大似然估计的动目标检测的非均匀方法，首先利用自回归方法对雷达接收数据进行时域白化处理，然后利用最大似然方法逐距离单元估计目标回波幅度，最后由估计结果与自适应门限比较得到检测结果。

The model of nonhomogeneous clutter environment is the precondition of the following research.3、Clutter non-homogeneity detector is studied, and a new clutter non-homogeneity detector is proposed by using frequency center idea for clutter spectrum shifting and nonhomogeneity of clutter power.

适合非均匀杂波环境的机载雷达接收数据模型为后续的适合于非均匀杂波环境的STAP方法提供了基础。3、研究了杂波非均匀检测器，针对杂波谱移动非均匀和杂波功率非均匀，提出了"频心"法杂波非均匀检测器。

This article gives an analysis,simulation and comparison of the performance of square demodulation ,Hilbert transform,wavelet transform,and nonlinear operator methods in extracting envelope spectrum of ship noise,and comes to the conclusion that their performanes are close.

分析并仿真比较了检波滤波法、希尔伯特变换法、小波变换法与非线性算子法等在提取舰船噪声包络谱中的性能，得出了它们性能接近的结论。

Chaotic signals' some characteristics make t1hem have natural invisibility, for example, they have nonperiodic continuous broader frequency spectrum and they are similar to noise. So, recently, chaotic synchronization and its application for secure communications attract wide interest.

混沌信号的非周期性连续宽带频谱，类似噪声的特性，使它具有天然的隐蔽性，因此近年来混沌同步及在保密通信中的应用受到了广泛的关注。

A important result is the one-order expression of AR Yt = DYt-1 + E, from paralleling a high-order differential equation transformation into a one-order differential equation system, the one-order expression exposes that the AR is only a certain more-multivariable power series processAnd, if a process is described as an AR, the sufficient and necessary condition is the spectrum norm A of the coefficient matrix D less than one.

作者用高阶微分方程化一阶微分方程组的方法，获得多元弱平稳序列p阶自回归模型的一步滑动平均表达式，证明了AR的是一个更高维的幂级数的线性过程，从而，说明了AR关于序列依概率成立的充要条件是：该模型更高维的幂级数的线性过程的表达式中系数矩阵D的谱范数λ＜1。

The energy calculation of the noncoherent despreading/demodulation signal was extended into vector norm calculation based on the equivalence property theory of vector norm in the orthogonal codes spread spectrum system.

依据向量范数等价性原理，将正交码扩频系统中非相干解扩解调信号的能量计算推广为向量范数的计算。

While the part of spectrum in the normal dispersion region would be flatter.

但其在正常色散区的部分光谱却更平坦。

However it can often be frust ating for a child when people are unable to pronounce their name.

但它往往可以令人沮丧的一个孩子当人们无法断言他们的名字。

All these compounds were obtained from this genus for the first time. Compound, 4-cumylphenol, was a new nature product.

所有化合物均为首次从本属海藻中分离得到，其中4cumylphenol为新天然产物。