查询词典 approximate partial derivative

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 definitions of generalized directional derivative and generalized gradient of Lipschitz functions defined on Riemannian manifold are presented. Some properties of the directional derivative and gradient are proved by using tangent and cotangent mapping. The minimization necessary condition of nonsmooth Lipschitz functions is given. Moreover, Fritz John necessary optimality condition in mathematical programming is provided on Riemannian manifold.

在黎曼流形上给出了Lipschitz函数的广义方向导数和广义梯度的概念，利用黎曼流形局部上与欧氏空间开集微分同胚的性质以及切映射和余切映射导出了广义梯度的性质和运算法则，证明了定义在黎曼流形上的函数取得极小值的必要条件是广义梯度包含零元素，并利用这些性质给出了黎曼流形上数学规划问题的Fritz John型最优性条件。

What's more the relations between different asset are classified to three groups which are the fundamental-derivative relation、the cross sectional relation and the comprehensive relation, on basis of which the asset pricing anomalies are classified individually to different groups.(2)The price model of the capital asset is constructed trailing the path of the asset value's incrementing and transferring. And then a three–factor model is established which can be utilized by the empirical researches. Concretely, under the capital chain, we conclude the relation between the stocks and the corporate assets is a fundamental-derivative one and the research object is the capital asset under the capital chain.

具体而言，本文在资产链的角度下分析股票和公司资产之间的"基础—衍生"关系，明确了本文的研究对象为资产链下的资本资产；建立了公司资产的价值，将公司资产和其基础资产公司的财产联系了起来，构造了资产链上第一个节点——公司资产的价值；将公司资产和资本资产进行了关联，在考虑公司资产变为资本资产的流动性增值后，建立了资本资产的价格模型；在前文资本资产价格模型的基础上进行了收益分解，基于此引入了具有长中短不同决策周期的三类投资者，在存在无风险资产和不存在无风险资产两种情况下分别建立了可用于实证的三因素模型。

This curriculum primary coverage includes: Function and limit, a circular function derivative and differential, theorem of mean and derivative application, indefinite integral, definite integral, definite integral application, space analytic geometry and vector algebra, function of many variables differential method and application, multiple integral, curvilinear integral and surface integral, infinite series, differential equation.

该课程的主要内容有：函数与极限，一元函数的导数与微分，中值定理与导数的应用，不定积分，定积分，定积分的应用，空间解析几何和向量代数，多元函数微分法及其应用，重积分，曲线积分与曲面积分，无穷级数，微分方程。

Week 5 The definition and nature of derivative, the geometric meaning of derivative, the relation between the derivability and the integral, derivation rule.

第4周 连续的定义，连续函数的性质，初等函数的连续性，闭区间上连续函数的性质。

On the basis of method of derivative on the left and the right of separable function,the derivability of separable function on demarcation point was simply distinguished,and derivative continuity on demarcation point discussed.

运用研究分段函数的导函数的左、右极限的方法，简便地判明分段函数在分界点处的可导性；同时讨论了分界点处导数的连续

Based on the quotient of difference being the grey derivative's whitening values in the GM(1,1) direct modeling method, direct modeling method of GM(1,1) with a step by step optimum grey derivative's whiting values is put forward.

在 GM(1，1)直接建模法以差商作为灰导数白化值的基础上，提出了一种逐步优化灰导数白化值的方法。

We get theexistence theorem of directional derivative of convex fuzzy mapping, and discuss the relationsamong directional derivative, differential, gradient and subdifferential.

得到了这类模糊映射的凸映射的方向导数的存在性定理。

Based on the simulated data produced by PROSAIL model and field test data, the authors respectively analyzed many kinds of factors which affect some representative inversion method s, such as VI, second derivative, model inversion and the directional second derivative.

以PROSAIL模型模拟数据和地面实测数据为基础，分别分析了土壤背景、冠层反射率非各向同性以及随机噪声等因素对几类代表性反演方法的影响(植被指数法、二阶微分法、模型反演法以及方向性二阶微分法)。

Since the B-spline is a locally supported function, the smoothing formula can be strictly limited in a neighborhood of each point. The smoothing surface defined by the smoothing formula has the same convexity as that of the original image. Secondly, the edge points are detected by either computing the local extremum points of the directional derivative or computing zero-crossing of the second-order directional derivative of the smoothing surface. Finally, an example of an edge detector is given.

针对反卷积视觉模型的病态性，增加了适当的约束，给出了基于低松弛迭代格式的快速自适应滤波算法，对于一个N×N输入图象，由于变换核的局部支撑性质以及低松弛迭代格式的引入，使得快速自适应滤波算法的计算复杂度降为象素个数N〓的线性量阶N〓，就最小二乘算法的复杂性而言，优于不动点迭代算法的O以及基于FFT的预处理共轭梯度算法的O。

The shaping method of noncircular part and the tool holder's radial motion characters in noncircular turning process are discussed in detail in the thesis.

论文详细研究了非圆零件的成型方法和加工过程中刀架的径向运动规律。

I have not really liked him,I do not like his this kind of disposition.

我没有真的喜欢他，我不喜欢他的这种性格。