导数

After the airdrop experiments of the system of the projectile and speed-down parachute, the balance velocity obtained from the optics apparatus on the ground、the balance spinning speed obtained from the gyroscope on the projectile and the image obtained from the infrared detector on the projectile are all used to simulate the six-dimension exterior trajectory of the projectile and identify the roll damping moment derivatives, and the identification can safely come to a conclusion that the absolute value of roll damping moment derivatives from the engineering calculation are on the low side.

对卷弧尾翼弹与减速伞系统进行空投试验，由地面光测系统给出平衡落速、弹上陀螺给出平衡转速、弹上红外探测器拍摄地面图像判断弹的姿态。通过六自由度弹道模拟，对弹滚转阻尼导数进行参数辨识，得到工程估算所得滚转阻尼导数绝对值偏小的结论。 5。对空投试验中出现弹姿态摆动现象，从受力分析及红外图像分析两个方面进行探讨，给出合理解释，并根据分析对弹外形进行修改，在后来的试验中收到很好的效果。

Firstly, this paper investigated roundly the basic theory of the ambient vibration method, analyzed systematically the main methods of ambient vibration identification, and discussed their advantages and disadvantages. Then we established the finite element model of structural dynamics and test model and analyzed their mutual relation, improved MUSIC method and correlation function method in the harmonic identification, and gave the subspace method and correlation function method based on continuous model, which is multi-harmonic retrieve technique. And then, this paper also puts forward least-squares method to estimate directly structural physical and modal parameters; this approach replaced the derivative operator in the continuous time model with an equivalent approximation, and estimated the physical parameters of structures by the least-squares method. And then, we discussed the approximation methods of derivative and their convergence. Finally, this paper researched the modal parameters of a frame structure by the simulation and test. The results demonstrated that subspace method, correlation function method and the least-squares method are effective and stable respectively.

全面地研究环境振动识别方法的基本理论，系统地分析环境振动识别方法的主要方法，讨论它们的优点和不足；建立结(来源：6666AB44C论文网www.abclunwen.com)构动力学的有限元模型和试验模型，分析有限元模型与试验模型之间的相互关系；改进谐波识别中的MUSIC识别方法和相关函数识别方法，给出大型结构模态识别的连续型的子空间分解识别方法和相关函数识别方法，这个方法是多元谐波识别方法；提出直接识别结构的物理参数和模态参数的最小二乘方法，这个方法利用导数的近似值代替导数值，并运用最小二乘方法识别结构的物理参数，讨论导数近似值的选择方法，分析算法的收敛性；通过仿真计算和模型实验，研究高层框架结构的模态参数识别，验证子空间分解识别方法、相关函数识别方法和最小二乘识别方法的有效性，算法的稳定性；从理论和试验两个方面分析和研究噪声对识别精度的影响，影响识别精度的因素，以及部分模态成分的模态参数不能够被识别的原因。

The tether was modeled using finite difference approximation. The balloon was modeled using rigid-body dynamic model including the static derivative, dynamic derivative and added mass.

缆绳采用有限差分法，球体采用经典的六自由度方程，其中气动力导数以静导数、动导数和附加质量表示。

Through model test and data analysis, it is found that the precision of the FFT method is much higher than that of the Fourier Series method in vertical derivative calculation.

通过模型试验和数据分析，发现在计算垂向导数时波数域求导算法的精度比傅氏级数的精度有明显改善；而水平导数的计算，2种方法的精度相当。

E. , the Frechet derivative is the first order of Zhang's integrated geometric factor. With the help of FEM, the calculation of the Frechet derivative is carried out conveniently, and its efficiency and accuracy are recommendable.

同时给出了均匀背景条件下Frechet导数结果，并且巧妙地解决了利用有限元素法计算Frechet导数的问题，获得了较高的运算效率和计算精度，从而使经典的有限元素法具备了求解测井响应和进行Frechet导数精确计算的双重功能。

The procedure estimating the regularization parameter is the same as that the adaptive Marquardt algorithm used. The Frechet derivative is directly derived from the forward methods: SAM and FEM. With the theory of SAM and Zhang′s geometric factor, the relationship between the Frechet derivative and the geometric factor is established, at the same time, one useful corollary is given, i.

选取正则化因子时，沿用自适应的Marquardt算法中阻尼因子的选取计算方法；计算Frechet导数时，根据逐次逼近解法和张氏几何因子理论，推导出了Frechet导数与张氏几何因子的关系，得出了Frechet导数为张氏一阶积分几何因子的结论。

The derivatives of the nonsmooth equations are computed to make the generalized derivative matrix nonsingular. Then the nonsmmoth damped Newton method is used to solve them.Analytic solutions of the KdV equation with variable coefficients: Shallow water wave problems belong to problems of free surface wave, and can be molded by the nonsmooth equations model given above in principle.

在前面建立的非光滑方程组数学模型和固定网格法基础上，利用广义导数的概念给出了求解渗流自由面的一种新方法-----非光滑阻尼牛顿法，该法是对非光滑方程组求导，适当的处理广义导数矩阵使其非奇异，利用非光滑牛顿法求解。

Because of the condition of 〓 for two neighbour parametricspline surfaces is too strong,here,instead of it,some simple and practicableconditions of 〓 resulted from the general theorem obtained by Prof.LiuDing Yuan in Chapter 1 were proved,and three 〓 triangular splinesurfaces schemes wre presented:one is piecewise cubic spline surface patcheshaving local 〓 and whole 〓 continuity based on the refined HCTtriangulation,another is the same degree spline surface patches but based onthe refined Powell-Sabin triangulation,the third is piecewise quartic splinesurface patches having local 〓 and whole 〓 continuity based on therefined P-S triangulation.

由于对参数曲面，一阶导数连续的要求较强，我们采用第一章从刘鼎元定理导出的简单实用的几何连续条件，讨论了基于HCT加细三角剖分和P-S加细三角剖分上的两种局部达一阶导数连续而整体有一阶几何连续的分片三次样条曲面构造算法，一种局部达二阶导数连续整体有一阶几何连续的分片四次样条曲面构造方法。

In order to solve the derivation of power exponent function,this paper has studied the derivation regulations on power function from the perspective of the differentiation of multi-variable function and in accordance with the derivation laws on multi-variable complex function.

为解决幂指函数的求导问题，从多元函数微分法的角度出发，根据多元复合函数的求导法则，探索幂指函数求导的规律，并揭示了幂指函数与幂函数及指数函数导数间的关系，给出了幂指函数求导的另一种方法。

It shows that the δ-derivative is identical with the derivative of finite discrete function when the sample points are increased.

引入了连续函数的δ导数新概念，研究表明，在采样点无限增多的情形下，它与有限离散函数导数概念相一致；在极限情形下，它与常规意义下连续函数导数概念相一致。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。