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Equidistance point and difference theory in theory of function approximation are studied. Meanwhile, the relation among difference, difference quotient and derivate is revealed. By drawing Lagrange's and Cauchy's theorem of mean on difference and Taylor's formula into difference function, four theorems, such as Lagrange's theorem of mean on difference, are concluded in simple way. On the basis of these conclusions, the asymptotic property of middle point is studied, a series of new conclusions are drawn and the discussions on the asymptotic property of middle point in differential mid-value are summarized.

对函数逼近论中等距节点和差分理论进行了研究，揭示了差分、差商与导数之间的联系；将Lagrange中值定理、Cauchy中值定理、Taylor公式引入到差分函数中，简明地推导出Lagrange差分中值定理等4个定理，并在此基础上对"中间点"的渐近性进行了研究，得出了一系列"中间点"的渐近性的结果，概括了有关文献对微分中值公式的"中间点"的渐近性的讨论；给出的引理改进了函数逼近论的证明方法，精简了函数逼近论中的一些内容。

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。

In this paper, firstly, the embeddability of near-triangular graphs on the orientable surface is studied. By using Petersen's Theorem about 1-factor, we first prove that for a near-triangulation on the orientable surface, its geometry dual graph has a 1-factor; then after a procedure of operation leaded by the 1-factor, we show that if a graph G triangulates some orientable surface S_g, then G has a near-triangular embedding in S_h for h = g,g + 1,...,β(G/2」, where β is the Betti number of G. Hence we obtain a conclusion: A near-triangulation of the orientable surface is upper-embeddable. As a generalization, a class of near-quadrangulation is studied, and similar results are obtained.

本文首先研究了近三角剖分图的可定向曲面嵌入性质，通过运用Petersen关于1-因子的定理，首先证明了对于可定向曲面上的三角剖分图，其几何对偶图具有1-因子；然后在1-因子的导向下，通过做一系列增加亏格的手术，证明了如果一个图G三角剖分可定向曲面S_g，那么G可以近三角剖分可定向曲面S_h，这里h=g，g+1，…，「β(G／2」，β是指图G的Betti数，从而得出推论：可定向曲面上的三角剖分图是上可嵌入的，作为推广，又研究了一类近四角剖分图的可定向曲面嵌入性质，并得到类似的结论。

However, the stress load alters in the proximal femur following THA, leading to "adaptable bone reconstruction", which is characterized by thin cortical bone, decreased bone density, and bone loss surrounding prosthesis, in particular calcar femorale.

但是全髋关节置换后股骨近端应力负荷会发生改变，导致股骨近端的所谓"适应性骨重建"，其特点是皮质骨变薄，骨密度下降，引起股骨近端假体周围，尤其是股骨距区骨丢失。

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。

F〓 of transgenic allotetraploid fish containing"all-fish"transgene——pCAgcGHc was obtained respectively by inbreeding and gynogenesis. Positive rate of pCAgcGHc detected by PCR was 90％ in F〓 of transgenic allotetraploid fish produced by inbreeding, while most F〓 of transgenic allotetraploid fish produced by gynogenesis showed diploidy measured by flow cytometer. The results above imply that developing the pure line of transgenic allotetraploid fish through inbreeding is feasible, but the operation should be modified if gynogenesis is introduced.

采用近交和雌核发育方法培育出转pCAgcGHc基因异源四倍体鲫鲤F〓代，通过PCR检测，外源基因pCAgcGHc在近交转pCAgcGHc基因异源四倍体鲫鲤F〓中的整合率为90％，而流式细胞技术检测雌核发育转pCAgcGHc基因异源四倍体鲫鲤F〓的倍性多为二倍体，说明通过近交筛选转基因异源四倍体鲫鲤纯系的方法是可行的，但是通过雌核发育来筛选转基因异源四倍体鲫鲤纯系还要就方法上进一步的改进。

The problem of how the coherent structures in the wall region of a turbulent boundary layer could be excited by the disturbances from the outer region was investigated by using direct numerical simulation method.

应用直接数值模拟的方法，研究了湍流边界层近壁区由于外区扰动的作用而导致相干结构产生的问题·结果表明：在湍流边界层近壁区的上边界存在的速度扰动，可以在近壁区内激发出相干结构，从而完善了单个相干结构的理论模型

Four parts that compose the thesis are as following: The first part discusses the pragmatic differences of the symonymly monosyllable and disyllable nouns through analyzing and contrasting their meanings, and classifies them into several categories.

本文共分为四个部分：第一部分通过对近义单、双音节名词词义的对比分析讨论对应的近义单、双音节名词在语义上的差异，并归纳出近义单、双音节名词词义区别的若干类别。

This paper presents a new type control method-the mixture trending law,which based on the exponential trend law,variable rate trend law and the saturated function.

在分析2种控制不足的基础上，提出了基于指数趋近-变速趋近-饱和切换函数的混合趋近控制律，并进行了对比仿真试验分析和实验研究。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。