查询词典 second derivative

The apparatus (40) further comprises a second mixer (42) with a second mixer input (45), a second local oscillator input (48), and a second mixer output.

该装置(40)进一步包括具有第二混频器输入(45)、第二本地振荡器输入(48)、和第二混频器输出的第二混频器(42)。

We applied ATR Fourier Transform Infrared spectra and second derivative spectra to analyze the alcoholicity and content of sugar of red wines produced by different manufacturers for the first time.

首次采用衰减全反射傅里叶变换红外光谱法并结合二级导数谱对市售的若干种不同厂家葡萄酒的酒精含量和糖含量进行了快速无损分析。

Three analysis methods were used in this study to analyze the content of amygdalin , and the effective components in bitter apricot kernel, namely, HPLC method, UV-Spectrophotometric method and Second-derivative spectra method.

苦杏仁的有效成分苦杏仁苷经提取、处理后，用HPLC法、紫外分光光度法、二阶导数光谱法测定其含量。

Mean angular acceleration and the increment of angular coordinate as well as the first and second derivative of angular with respect to time is not only the physical quantities which often being used but also important physical quantities.

无限小角位移、有限大角位移、角速度、平均角速度、角加速度、平均角加速度和角坐标的增量以及角坐标对时间的一阶和二阶导数不仅是物理学中常用的物理量，而且也是很重要的物理概念。

For another, reduced-space approaches allow to exploit problem-dependent structure and approximate second derivative information.

简约空间方法适合过程系统优化命题的高维、低自由度特征，并可利用问题结构和近似二阶信息求解，是该类优化命题的良好求解途径。

Local discontinuous Galerkin method for convection-dominated diffusion problems with periodic boundary conditions is constructed. To deal with the derivative of second order, an auxiliary variable is introduced. The stability and error estimations are presented simultaneously.

针对具有周期性边界条件对流占优的扩散问题中的二阶导数，引入辅助变量，构造了局部间断Galerkin方法，并给出了方法的稳定性结果和误差估计式。

Numerical simulations of the three dimension viscous flow over the SUBOFF-1 model provided by DARPA and other two models are processed by solving RANS equations withκ-εtwo-equation turbulence model and finite volume method, and with SIMPLEC method for pressure-linked terms, central difference shemes for temporal derivative terms, and second-order upwind schemes for convective and diffusive terms.

本文基于RANS方程，采用κ-ε两方程湍流模型来封闭控制方程，采用有限体积法离散控制方程，对于速度压力关联方程，应用协调一致的SIMPLEC算法求解，变化率项用中心差分，对流扩散项采用二阶迎风格式，分别对DARPA提出的裸艇体SUBOFF-1模型以及另外两种回转体模型进行了数值模拟计算。

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。

The observed pressure derivative curve shows a concave shaped curve like a dual porosity behavior, but the curve never reaches the second flat state.

观察到压力导数曲线呈凹状曲线就像一个双重介质行为，但该曲线从未到达的第二个单位。

The witness also told the jury at the Royal Courts of Justice in London that he saw a paparazzo fighting with a member of the public who was trying to stop him taking pictures in the minutes before the emergency services arrived.

他还告诉在伦敦皇家法庭的陪审团，在急救服务到来之前，他当时看见一个狗仔队正和一群阻止他拍照的人打架。

The entire N／C program on a tape is made up of an accumulation of these successive data blocks.

纸带上的整个数控程序由这些连续数据单元连接而成。