渐

It is proved that, when the value of critical threshold less than 1, the disease free equilibrium point is globally asymptotically stable. Further more, Bursaphelenchtis Xylophilus is used to construct the Lyapunov function, and the stability theory of Lyapunov function is used to prove that the equilibrium point is Global asymptotic stable. It explains that the Bursaphelenchus Xylophilus wiil eventually disappear.

证明了当临界阈值小于1时，无病平衡点是局部渐近稳定的，进一步利用巴尔巴欣公式构造Lyapunov函数，运用Lyapunov稳定性理论证明了该平衡点的全局渐近稳定性，说明松材线虫病会最终消失；当临界阈值大于1时，病虫害平衡点是局部渐近稳定的。

First, in the construction asymptotic expansions, it does not need to perturbations of the structure so special series of assumptions, or the need for a asymptotic matching, but generated its own approaches applicable to the asymptotic series.

首先，在构造渐近展式时，它不需要对摄动序列的结构做特别的假设，也不需要使用渐近匹配，而是生成自己的适用于问题的渐近序列。

It is shown that a continuous flow with the AASP is chain transitive and some equivalent conditions of the continuous flow with the AASP to be chain recurrent are obtained.

对连续流引入渐近平均跟踪性质概念，证明具有渐近平均跟踪性质的连续流是链传递的，同时对具有渐近平均跟踪性质的连续流给出链回归的几个等价条件。

Third, the discussion of the corresponding relationship of the real angles to the apparent real angles is performed, the asymptotic bias and MSE of real angles are given. Fourth, based on above conclusions, the analysis of two typical cases is made by numerical analysis and computer simulation: Case A when the impinging signals are divided into desired signals and interfering signals: it is shown that similar to Cyclic estimation of DOA, the smaller the separation between interfering direction and signal direction, in general, the smaller the estimation variance.

首先，研究了无穷快拍时信号数目有误的最大似然估计，引入了视在真实角度的概念；其次，导出了视在真实角度最大似然估计大样本时的分布以及渐近均方误差的解析表达式，而且还证明了：Stoica性能分析结果是现在的分析结果在信号数目准确时的特例；第三，讨论了真实角度与视在真实角度的关系，给出了真实角度的渐近偏和渐近均方误差；第四，依据前面的结果，利用数值分析和模拟实验的方法对两种典型情况做了分析： 1 在入射信号被分为干扰信号和所需信号情况下：结果表明：与CyclicDOA估计一样，干扰方向与所需信号方向靠的越近，所需信号估计的方差越小，越远离，方差越大。

We build the model for the enveloping worm helix parametric equation and then analyze its relations with the enveloping worm helix tooth surface equation,thus establishing the characteristic model of the involute helicoid enveloping worm′s generative gears.

渐开面环面蜗杆的三维构建属复杂曲面造型，文章在环面蜗杆螺旋线参数方程建模的基础上，分析讨论了其与渐开面环面蜗杆螺旋齿面方程的对应关系，建立了渐开面包络环面蜗杆产型齿的特征模型。

We establish an asymptotic Lipschitz homotopy invariance theorem for these K-homology groups and K-theory groups. We show that the asymptotic index maps are isomorphisms for the asymptotically scaleable spaces, which include Euclidean cones, simply connected complete Riemannian manifolds with nonpositive curvature.

我们证明了这些K-同调群和K-理论群具有渐近Lipschitz同伦不变性；对于渐近可标度的几何空间（包括欧氏锥、单连通非正曲率完备黎曼流形等），证明了渐近指标映射为同构。

The deduced integral invariant is employed to study the 3D predator-prey Lotka-Volterra systems and some new results are obtained.

利用此积分不变量，对三维捕食被捕食 LVS解的渐近性进行讨论，得到了平衡点全局渐近稳定的新条件，推广了已有LVS正平衡点全局渐近稳定的结

Keywords asymptotic waveform evaluation;size dimension;Power/ground planar structure;impedance characteristics;adaptive sectional method;Laurent series expansion;broad-band asymptotic waveform evaluation;multi

渐近波形估计技术；尺寸维；电源/地平面结构；阻抗特性；自适应分段方法；洛朗级数展开；宽带渐近波形估计技术；多维渐近波形估计方法；自适应跳点技术；参数提取；电源完整性分析；参变分析

For the compressible materials, in order to satisfy the higher-order compatibility equation of the rate of deformation in the centered fan sector, which is a quite difficult problem unresolved in the previous studies, a particular term must be added to the expansions of the stress components in the regular logarithmic power series adopted by many researchers before. A higher-order near tip field with tangential velocity jump ahead of the crack tip is derived first, of which the dominant terms are the solution widely accepted.

对可压缩材料，本文首先采用非规则的对数幂级数渐近展开方法，克服了过去研究中存在的中心扇形区变形率协调方程的高次渐近式不能被满足的困难，并得到了一个切向速度在裂尖前方存在间断的高阶渐近解，该解的主项就是目前被广泛接受的关于可压缩材料的尖端场解。

The detailed comparisons between the higher—order near tip solution and the well—known modified Prandtl field are also given in this paper.For the compressible materials, in order to satisfy the higher-order compatibility equation of the rate of deformation in the centered fan sector, which is a quite difficult problem unresolved in the previous studies, a particular term must be added to the expansions of the stress components in the regular logarithmic power series adopted by many researchers before. A higher-order near tip field with tangential velocity jump ahead of the crack tip is derived first, of which the dominant terms are the solution widely accepted.

对可压缩材料，本文首先采用非规则的对数幂级数渐近展开方法，克服了过去研究中存在的中心扇形区变形率协调方程的高次渐近式不能被满足的困难，并得到了一个切向速度在裂尖前方存在间断的高阶渐近解，该解的主项就是目前被广泛接受的关于可压缩材料的尖端场解。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。