可近似性

The results suggest: the three culturalss pollen germination percentage were more than 60% 4 h after cultured in liquid culture medium composed 10% sucrose, 24℃; Florescence most concentrated April third-tenth (2003); For Zaomeisu and Qiyuesu ,their anthotaxy and flower self setting fruit percentage were more than 90%,except for China pear 1, anthotaxy self setting fruit percentage was 48.3%, flower self setting fruit percentage was 33.1%; Their cross-compatibility was higher, anthotaxy and flower self setting fruit percentage almost reached 100%, the lowest also reached 94.9%, but last self-compatible gathering fruit percentage was lower comparatively and fruit average seed numbers were lower, while cross-compatible gathering fruit percentage and fruit average seed numbers were closed to that of nature pollination.

对梨品种亲缘关系很近的早美酥、中梨1号、七月酥等进行的花粉发芽率、花期调查、自交亲和性、异交亲和性调查的结果表明：三者的花粉在10%的蔗糖液培养基上，24℃左右培养4h后花粉发芽率均能达到60%以上；三者的花期大都集中在4月3日-10日(2003年)；早美酥、中梨1号、七月酥的自花授粉坐果率，除中梨1号的花序自花授粉座果率为48.3%，花朵自交座果率为33.1%外，早美酥、七月酥的花序自交座果率和花朵自自花授粉座果率均达到90%以上；它们的异花授粉坐果率更高，在本试验中花序坐果率和花朵坐果率都可达到94%以上，但最终采果率自花授粉的相对低一些，果实平均种子数也低，异花授粉的最终采果率和果实平均种子数与自然授粉条件下的近似。

This value is prescribed only vaguely by many authors with no reference to any significance level. This paper will give out an asymptotic critical value in a fixed significance level and an asymptotic p-value for testing by means of extreme value theory in order to detect outliers in AR model.

本文运用极值理论给出诊断AR模型异常点选取临界值的分布近似方法，这种方法选取的临界值可保证控制在一定的显著性水平下，而且还可以计算出检验的渐近p值，比一般仿真选取的临界值更科学合理。

By means of deriving the approximate solution and a process of approaching iteration, we have shown that a general solution exists for a non-Newtonian compressible fluid in 3D bounded domains. The proof is based on an elementary energy method.

文章利用构造近似解和极限的过程证明了三维有界区域中非牛顿可压缩流体广义解的存在性，所用的证明方法为能量方法。

The question of searching characteristic points or straight lines on moving rigid body is decomposed into two relatively independent sub-questions. The first one is to evaluate the characteristic of points and straight lines on moving rigid body, whose mathematics model is a kind of special non-differential max-mini optimal problem with inequality constraints. By the method of Saddle-point Programming and maximum entropy, the problem can be transformed as a differential optimal problem with single objective. The second oner is to search approximative character points or straight lines on moving rigid body within design space, whose mathematic model is nonlinear and non-differential problem with multiple constraints.

本文将在运动刚体上寻找特征点或直线的优化问题分解为两个相对独立的子问题，一是对运动刚体上点或直线的特征性评定，其实质是平面曲线的圆度或直线度的评定问题，优化模型是以最大误差为最小作为优化目标的约束不可微的优化问题，本文采用鞍点规划和极大熵方法，将其转化为单目标可微优化模型；二是在设计空间内，寻找运动刚体上特征性评定指标最小的近似特征点或直线，其优化模型是非线性、多约束的不可微优化问题，本文提出用遗传算法和BFGS局部搜索法相结合来求解。

The main points of this thesis are as follows: It is presented that the key issue to constructing of the orthonormal wavelet on the basis of multiresolution analysis theory is to design the wavelet bases which can be used to decompose the signal into a two-band form, while the construction of wavelet bases is equivalent to designing a filter bank with perfect or nearly perfect property restricted by regularity.

论文工作在以下几个方面取得了进展：提出用多尺度分析理论构造正交小波，最终可归结为构造能进行两带分解的小波基，而小波基的构造又等价于在附加正则性条件约束下，设计一个完全恢复和近似完全恢复的滤波器组。

Chassis seals model batholith to seal model to be different from general antirust processing, be a kind of tall adherent sex flexible spray of rubber tree fat is on chassis, because of its spray or diaphragm of substance of approximate balata form is formed after brushing besmear, make chassis and outside completely cut off, not easy and weather-shack, fall off, can prolong automobile body life.

底盘封塑底盘封塑不同于一般的防锈处理，是将一种高附着性的柔性橡胶树脂喷涂在底盘上，因其喷涂或刷涂后形成近似橡胶状物质保护膜，使底盘与外界隔绝，不易干裂、脱落，可延长车身寿命。

By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.

在窄带条件下，GSC－SSF方法还可以提高阵列的虚拟孔径，从而提高估计的性能；可以证明，Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似； 3、提出了二维GSC－SSF方法和宽带谱相关DOA矩阵方法，利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题，并具有阵元数少、计算量较小的特点； 4、提出了时频子空间拟合和宽带时频DOA估计算法，将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中，利用时变滤波实现信号选择性测向和干扰抑制，特别适合于谱时变信号；可以证明传统特征结构法可看作是时频子空间拟合方法的特例； 5、提出了多用户环境下阵列响应的估计方法——CARE方法，该方法对信号结构和传播参数（主要是散射源分布与角度散布）的约束较少，适用于各种几何结构的阵列甚至未校准的阵列，能够直接得到阵列响应的闭式解，因此计算量小、稳健性好，不存在收敛问题； 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案，通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束，并保证各波束内的用户信号各不相同且相互干扰最小；其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点，其有效性已得到外场实测数据的证实。

The results indicate that polyborazine precursor prepared at 150℃ for 10 h and propylamine/isopropylamine molar ratio 2:1, could possess nearly linear molecule skeleton and he prone to melt spinnability. When melt at 90℃, the precursor fibers are prepared with average diameter 10-20μm and BC1.27 N1.52 H structure. After curing process and sintered in NH3 at 1200℃, the near-stoichiometric BN fibers was obtained, which proved this precursor is apt for preparation of BN fibers.

结果表明，当正丙胺／异丙胺摩尔比为2：1，聚合温度为150℃，反应时间为10h时，合成产物具有近似线性分子结构，熔点为90℃，具有良好的成丝性，可获得平均直径10~20μm，组成为BC1.27N1.52H的先驱体纤维，先驱体纤维再经不熔化处理及1200℃氨气高温锻烧等工艺可获得近化学计量比的氮化硼纤维。

In addition, this method is used in the motion control study of spinning machine tool, and achieve good control effect

机床的工作台可视为直角坐标型的机器人，这类机器人是近似线性系统，可以采用比较复杂的迭代学习控制方法，因此，本文提出了弹性移动关节机器人的混合PID迭代学习控制律，证明了该方法的收敛性，并将这种方法应用于旋压机床的学习运动控制，达到了良好的控制效果。

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。