导数

The derivative of a function can be interpreted either as a function whose value at x is equal to the gradient of the tangent line to the graph of y=f at x, or, alternatively, as a function that describes the instantaneous rate of change of y with respect to x at the point x.

一个函数的导数可以理解为一个函数的值无论是在x是等于切线的梯度的y图二F在x，或者，或者，作为一个函数描述瞬时速度y的变化的关于x的点x在f关于x的也可以表示为导数

The pressure derivative curve will upwarp because of the existence of the threshold pressure gradient and the fault. The identification of the type of "upwarping" in the pressure derivative curve is crucial to the selection of the well testing model.

启动压力梯度和断层的存在都会使压力导数曲线发生"上翘"，对压力导数曲线"上翘"类型的识别，是正确选择试井解释模型的关键。

The fourth-derivative analysis was performed on the spectra to set up the uniform initial central wavelengths for excitation spectra of dinophyta and bacillariophyta,respectively,according to the position and number of maxima on the derivative spectra.

对其作四阶导数分析的基础上，根据导数光谱中出现的极大值位置和数量，对甲藻门和硅藻门的激发光谱分别设定统一的初始中心波长。

The databases of NIRDRS for Hypericum、 Eucalyptus globules and broussonetia papyrifera were established within suitable spectral ranges with three kinds of data block(original spectrum, first-order derivative spectrum and second-order derivative spectrum) to discriminate unknown samples.

分别用三种数据块(原谱、一阶导数光谱、二阶导数光谱)在不同的谱区范围建立了金丝桃、蓝桉、楮实子3种中药材的NIRDRS指纹图谱库，对未知样品进行鉴别。

Based on the improved Atiken iterative method and dimidiate method, a new algorithm of searching zero of derivative function is given, the simulation results show that if using the new algorithm to find the zero of derivative function, the convergence speed is faster than the improved Atiken iterative method .

采用二分法预报、改进的Aitken迭代校正的方法，构造了一种求导数零点的一种新算法。新算法在迭代过程中不用计算导数，且二阶收敛。数值试验表明，该算法具有较高的精度和较大的初值选择范

For high quality voice transformation, a novel parameter extraction scheme for glottal flow derivative is proposed based on Legendre orthogonal decomposition.

提出了一种用于源-目标说话人声门波导数参数转换的、基于勒让德正交分解的声门波导数波形参数提取方法。

By analyzing, an adaptive mode of linear filter based on DCT is given out. The curves of the vertical second derivative of gravity anomaly are matched well with those of the academic second derivative, and the calculating precision is much higher.

通过分析给出了基于DCT的合适的线性滤波方式，滤波后的重力异常垂向二阶导数与理论二阶导数拟合效果好，具有较高的计算精度。

In Chapter 1,some basic concepts and related qualities areintroduced,for example,Gateaux derivative,Fréchet derivative and the complexform for elliptic systems of equations etc.

第一章我们介绍了Gateaux导数和Fréchet导数的概念、有关性质以及椭圆型偏微分方程组的复形式与椭圆型条件等基础知识。

Measurirg indxes included:(1) Electrocardiograh;(2) Hemodynamics: cardiac output, pump output, aortic pressire, pulmo nary artery pressure, left atrium pressure, right atrium pressure, left ventricular end systolic pressure, left ventricular end diastolic pressure, LV-dp/dt, right ventricul ar end systolic pressure, RV-dp/dt, systolic pressure time index, diastolic pressure time index, endocardial viability ratio;(3) Myocardial metabolism: coronory sinus blood flow, myocardial oxygen consumption, myocardial lactate extractiorn;(4) Ischemic myocardial area;(5) Ultrastructure of myocardium.

测量指标包括：①心电图；②血流动力学：心输出量、泵输出量、主动脉压、肺动脉压、左房压、右房压、左室收缩末压、左室舒张末压、左室压的一阶导数、右室收缩末压、右室压的一阶导数、收缩压力时间指标、舒张压力时间指标、心内膜下心肌供血比率；③心肌代谢；冠状窦血流量、心肌氧耗量、心肌乳酸摄取量；④心肌缺血面积检查及缺血心肌的超微结构观察。

Several objective spins of solid cylinder torsion deformation were rendered and the large deformation elastoviscoplastic constitutive relationship s were derived for the Oldroyd stress rate,the generalizing Jaumann stress rate and the stress rate with respect to the spin of the frame of deformation rate with the aid of stress-strain curve from torsion test.

应用等向强化的J2流动塑性理论，建立了以扭转试验的应力—应变曲线为基准的，分别由Oldroyd、广义Jaumann应力导数和相对于变形率标架旋率的应力导数表述的大变形弹塑性本构关系。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐