查询词典 first derivative

Douglas and Russell first presented the idea of characteristics in[13],in whichthe diffusion term is included in the derivative of characteristic direction of the solu-tion and the backward difference quotient along the time axis was replaced by it alongcharacteristic direction.

Douglas，Russell[13]最先提出了特征法的思想，其主要特点是将模型方程的对流项隐含在解沿特征方向的导数之中，以沿特征方向的向后差商逼近取代通常方法中沿时间方向的向后差商逼近。

In this paper, a method of analysis which was based on thin layer chromatography was introduced. Benzimidazole derivative and amine were separated at first.

文中采用薄层层析法分离苯并咪唑衍生物及杂质，首先分离出苯并咪唑衍生物，然后用非水滴定方法分析含量，得到了准确的分析结果。

It is first discovered that guazatine can react with benzoin and its derivative has strong fluorescence.

首次发现双胍辛胺与安息香可发生反应，产物具极强的萤光活性。

However, it is very toxic. Nocantharidin, a derivative of cantharidin first synthesized in China, is a new anti-tumor drug with strong anti-tumor activities and increases the number of while blood cells.

去甲基斑蝥素(noncantharidion， NCTD)为斑蝥素的衍生物，是我国首先合成的具有较强抗肿瘤活性和独特升高白细胞作用的新型抗肿瘤药物。

Based on Bezier curve continuance of first－order and second－order derivative, the characteristic vector equation of two Bezier curve is presented in point of intersection. The algorithm is not only of high accuracy with all of the interpolated points being on the curve theoretically, but also of very high speed in the real－time interpolation processes. The interpolation velocity does not change and the segment tolerance of interpolation can be control by selecting the parameter in cerement rationally every time.

为保证两段Bezier曲线在连接点处一阶导数、二阶导数连续，导出了两段Bezier曲线特征向量应满足的关系方程，Bezier插补法不仅在理论上可使所有的插补点落在曲线上，而且实时插曲补速度高，每次插补时可合理地选择参数增量，能使插补速度保证不变，也可控制弓高误差。

The first and second derivative plates of concave pressure build-up curve are presented in this paper.

本文提出了凹型压力恢复曲线的一阶导数图版和二阶导数图版。

Furthermore, the first-order optimality condition and its equivalent reformulations for generalized semi-infinite max-min programming with a non-compact set are presented using the lower-Hadamard directional derivative and subdifferential.2. Chapter 3 studies the gradient-type methods for unconstrained optimization problems. Section 1 proposes a new class of three-term memory gradient methods. The global convergence property of the method is established. Furthermore, in order to improve the convergence property of the method, a new class of memory gradient projection methods is presented with the property that the whole sequence of iterates converges to a solution to the problem under the conditions such as pseudo-convexity and continuous differentiability of objective function. In section 2, two new classes of methods, called gradient-type method with perturbations and hybrid projection method with perturbations, are proposed. In these methods, non-monotone line search technique is employed, which makes them easily executed in computer.

第3章研究了无约束优化问题的梯度型算法，第1节提出了一类新的三项记忆梯度算法，讨论了算法的全局收敛性，进一步提出了一类新的具有更好收敛性质的记忆梯度投影算法，并证明了该算法在函数伪凸的情况下具有整体收敛性，第2节在非单调步长搜索下提出了带扰动项的梯度型算法及其混合投影算法，这两类算法的一个重要特征就是步长采用线搜索确定而不象许多文献中那样要求步长趋于零，这样更容易在计算机上实现，在较弱的条件下证明了这些算法的全局收敛性，数值算例表明了算法的有效性。

The first part is the preparatory knowledge, introducing the contracting mapping principle which through the basis of vector and matrix norm, derivative and differential theorem of mean to thorough understanding the nature of soluble for nonlinear equations.

第一部分为预备知识，重点介绍压缩映象原理。通过引入向量与矩阵范数，导数与微分中值定理，以求深入理解非线性方程组可解性的基本理论。

First, the partial derivative is defined, based on the convergence in probability measure in the probability measure space.

本文首先在概率测度空间上，利用依概率测度收敛，定义了多随机变量函数的偏导数，并且偏导数的计算式可以通过替换实值函数的对应的偏导数中所有的实变量替换为随机变量得到。

ADAMS. According to a function with STEP5 has features of continuous first and second derivative,the higher degree of approximation,etc.,we test and verify feasibility of fore-and-aft movement and turning gait of the robot. Thus a solution of the Snake-like robot motion under the ADAM...

ADAMS软件对蛇形机器人进行了从样机模型建立到运动学仿真与分析等一系列研究；并根据STEP5函数具有一阶与二阶导数连续、较高的逼近程度等特性验证了蛇形机器人前后移动和左右转弯步态可行性；找到了一种在ADAMS环境下求解机器人运动的方法，简化了理论计算，提高了设计效率。

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。