近似方法

Using the directional derivative formula, the governing equation is discreted in the physical domain in which a nonorthogonal grid system is used. Two kinds of AF2 schemes, i. e. AF2-plane relaxation and full implicit AF2, for the TSD equation are proposed. Numerical results show that the full implicit AF2 scheme converges faster than AF2plane relaxation scheme. For the rectangular wing and swept wing, the results of the present method are compared with FP results, and the agreement is good.

采用适合于梯形机翼和后掠机翼的斜网格，利用方向导数公式直接在物理空间对主管方程进行离散；将近似因式分解方法应用于绕机翼的跨音速小扰动势流问题，提出AF2—面松弛和AF2全隐式两种迭代格式，并对它们的收敛速度进行比较，结果表明后者明显快于前者；直机翼和后掠机翼的算例表明，本文方法的结果与精确势流方法的结果吻合良好。

Imagine that you would like to implement the hypothetical fubar statistic, and that you know two ways to calculate fubar on a bunch of samples: an accurate but slow calculation and an approximate but fast calculation.

想象一下你要实现假设的 fubar 统计，你知道两种方法来计算一组样本的 fubar：一种方法精确但计算速度慢，另一种方法近似但计算速度快。

Bootstrapping method is such a method that resolves ambiguity integer solution without searching. It is a approximate algorithm of LAMBDA method too.

Bootstrapping 方法是一种不必搜索的模糊度整数解的求解方法，是 LAMBDA 方法的一种近似算法。

Based on MLS and direct collocation,themeshless methods for function interpolation and solving elastic-static problem areestablished.Combining the advantages of direct collocation method and Galerkinmethod,the method based on least-square collocation is also proposed.

基于MLS近似和直接配点格式，本文建立了函数插值、弹性静力问题求解的无网格方法；结合Galerkin方法和直接配点法的优点，提出了最小二乘配点型的无网格方法。

No additional data for frequency tracking are need, but higher estimation accuracy and low computational complexity can be obtained. Finally, a kind of optimizing joint algorithm for symbol timing, frequency synchronization and channel estimation is proposed. The false alarm probability and miss detect probability of the symbol timing are derived. We proved that the time－frequency offset domain random sequence sliding in the frequency offset direction is orthogonal with the original random sequence, and proposed a new integer frequency offset estimation algorithm. The coarse estimation methods for fractional frequency offset both in AWGN and multipath channels are proposed too.

最后，提出了一种优化的符号同步、频偏估计和信道估计的联合算法，推导了符号同步方法的虚警概率和漏检概率，给出了随机序列在时间－频率偏移域沿频率偏移方向滑动后与原序列近似正交的证明，提出了一种新的在时间－频率偏移域沿频率偏移方向进行滑动相关估计整数频偏的方法，提出了在AWGN信道和多径信道下进行小数频偏粗估计的方法，给出了小数频偏细估计的ML估计结果和利用频域PN序列取值特性的简洁的信道估计结果。

The paper discusses moment estimation of parameters on Copulas with two kind of methods-moment estimation and approximate moment estimation, and compares two methods by simulation.

本文研究了Gumbel Copula函数的参数佑计，提出了矩估计和近似矩估计两种方法，分别得到了未知参数的估计结果，并通过模拟研究对这两种方法进行了比较，结果显示矩估计方法更为合理。

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。

The root-cause for the synchronous error of multiple axes of the vehicle panoramic sight platform was found after analysis with the geometric method. Since the synchronous error is caused by the windage angle produced in the working process of the optoelectronic platform, the method to correct the angular deviation at any distance is proposed. The experiment for solving the problem was implemented. The experiment indicates that the method is valid.

针对车载周视观瞄平台异轴同步性问题采用几何作图法进行分析，得到异轴同步问题产生的根源是不同光电平台转动过程中由于存在偏差角所致，对校准距离情况下的角偏差，距离小于校准距离情况下的视差和距离大于校准距离情况下的角偏差在3中不同区间的修正方法进行分析并进行等效近似，给出程序实现方法，最后用实验验证了此方法的正确性。

We used different methods to calculate luminosity in order to assure its reliability. Structure function method is adopted to derive the radiatively corrected cross section whose accuracy is up to 1%. The corrections from vacuum polarization and effect of energy spread are also studied. The final analytical approximation formulaes of the observed cross sections are worked out. Different fitting methods are carried out to fit the resonances according to different requests.

模拟的分布图的仔细对比，并兼顾实验的要求，得到每种事例对应的选择条件，特别是在处理积分亮度时，更是采用了不同的方法，以保证亮度计算的可靠性；采用结构函数的方法推导出截面的辐射修正公式，精确度达到了1％的水平，研究了真空极化给拟合公式带来的修正，并考虑了束流能散的影响，计算出最终的观测截面的解析近似式；对于三个共振态的拟合，针对不同的要求，采用了不同的拟合方法；同时在M.C。

At the same time, pattern recognition has been used for abstracting characteristics、predicting the life and evaluating the properties of engine. This research contributes toward global diagnosis for the diesel engine in eight ways.(1) Put forward"the Arithmetic of distinguish the period automatically using auto-correlation method";(2) Separate the waves of continuous knocks using WV distribution;(3) Propose"the logarithmic spectrum approximate method"to analysis the response of the knock between the steel and steel;(4) Discuss the relationship between the time-frequency distribution and timescale distribution in detail, and give the principle of classification;(5) Use the wavelet method to analysis the pressure signal of exhaust、suction;(6) Use the shape of vibration signal to analyse the working situation of cylinder;(7) Use the pattern recognition to select the good samples and abstract the effective characteristics;(8) Develop the model of total properties evaluation and life prediction.

本文在广泛的、深入研究的基础上，应用多种信号处理手段来分析处理数据，同时利用模式识别方法对故障的特征提取、寿命预测以及性能评价作了探讨，本文进行了以下几项工作：（1）提出了基于自相关自动周期识别算法的柴油机振动信号预处理策略；（2）提出了基于WVD分布的连续撞击响应信号的分离策略；（3）提出了基于对数谱拟合方法的钢—钢撞击响应求解模型；（4）提出了基于波形分析的非正常燃烧振动信号的诊断模型；（5）提出了基于小波细节信息的进气压力信号和曲轴箱压力信号的诊断模型；（6）提出了基于小波近似的喷油正时信号中燃烧位置的自动定位；（7）提出了基于统计模式识别方法的故障诊断知识的自学习与自组织策略；（8）提出了基于特征压缩思想的柴油机总体性能评价及寿命预测模型。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。