导数

Thirdly, in order to improve the learning efficiency and stability of feedforward neural network, a fast learning algorithm for neural networks based on CGM-OC approach is presented. Compared with other learning methods such as BP method, Broyden Flecher Goldfarl Shanno method and Powell method in which the derivative is replaced by the difference quotient etc, simulation results show that the proposed method is an efficient and fast one.

第三，为了提高前馈神经网络权值的学习效率及稳定性，提出一种基于正交校正共轭梯度优化方法的神经网络学习算法，通过与其它学习算法（如：BP算法、变尺度法、用差商近似代替导数的Powell法等）的比较，经仿真试验表明，本算法是一种高效、快速的学习算法。

The weight values in NLSM were adjusted automatically according to target data, which allowed the measured data with different dimensions or ranges to be treated at the same level, and thus the accuracy and stability of algorithm were improved accordingly. Derivative was replaced by the difference quotient in NLSM which further improved the algorithm speed.

非线性最小二乘法的权值根据目标数据自动调整，使得不同量纲和不同数值范围的观测数据可以在同一水平上进行，提高了计算的精度和稳定性；另一方面用差商近似代替导数加快了算法的收敛速度。

Theorem 1 Suppose the function is differentiable at,then its partial derivative at exist, and the total differential of

定理1如果函数在点可微分，则该函数在点的偏导数必定存在，且函数在点的全微分为。

As we all know, if the two partial derivations of binary function are continuous ,the function is differentiable.

摘要众所周知，当二元函数的两个偏导数都连续时，函数可微。

Theorem 2 If has continuous partial derivatives at , then is differentiable at .

定理2如果函数在点的偏导数连续，则函数在该点可微分。

Be differentiable at . Then has first partial derivatives at , and

可微，则复合函数在点的一阶偏导数存在，且有

The combined mathematics of differential calculus and integral calculus.

微积分学中有关用导数与微分的观念讨论函数随独立变量改变的部分。

By definition, we can see that the marginal analysis of differential calculus is essentially a derivative of the application.

由定义可知，边际分析法实质上是微分学中一阶导数的应用。

The high-rank differential coefficient of error is one of the necessary parts which influence the system track precision.

误差的高阶导数是影响系统跟踪精度不可缺的一部分。

Which is called the arc differential of the curve.

设函数在区间内具有连续导数，且曲线上点的弧长为，则弧长的微分是。

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。