查询词典 differential method

Based on the governing differential equations of the transient problem of temperature fields with phase change, the two-dimensional finite element formula of computing temperature fields around a buried pipeline in permafrost regions are achieved by using Galerkin's method.

根据相变瞬态温度场的控制微分方程，应用Galerkin法推导出计算温度场的二维有限元公式，对中国东北多年冻土区运行30年的加热输油管道土壤温度场进行了计算分析和比较。

Based on conformal mapping and differential geometry theory,a triangular mesh parametrization method by optimizing deformation energy is proposed in the paper.

本文首先基于保形映射和微分几何相关理论，定义了一种统一衡量参数化的角度变形和面积变形的变形能量。

Based on the equilibrium equation of an arch element the cubic nonlinear dynamic model with second order is established and the nonlinear differential dynamic system without constant term is obtained through a transfer process of T=U+b. Hence three fixed points and the homoclinic orbits are found. The critical condition of the chaotic vibration of the elastic arch is given by using the method of Melnikov function. The numerical results of the stationary and chaotic motion are given and discussed.

首先利用拱的单元平衡方程建立了拱的二阶三次非线性动力学模型；然后通过变换使方程转化为不含常数项的非线性微分动力系统，并由此得到无扰动系统的3个不动点与同宿轨道；再用Melnikov函数法给出了发生混沌的临界条件；最后给出了该系统出现定常运动和混沌运动的数值结果。

Our approach consists of the following steps: providing a sketch based mapping between the sources and the target; deforming the target based on the deformations of the corresponding sources by means of differential mean value coordinates; smoothing the deformed target with constrained minimization method to form a key frame of the target animation; and interpolating between key frames created from to produce a complete 3D animation of the target.

该框架由以下几个步骤组成：使用草图在源网格和目标网格间建立映射；使用非闭合网格均值坐标，根据源动画的运动风格来变形目标网格；对变形后的目标网格求解最小化约束函数以获取光滑的目标网格，从而生成目标动画的关键帧；对由产生的结果进行插值，产生完整的目标对象的三维动画。

Derive the equations of continuity by using the method of infinitesimal based on the mass balance equations and the differential equations of gas and oil phase fluid flow.

再根据物质平衡原理，利用微元法分析凝析油气渗流规律，建立连续性方程，从而导出凝析油气渗流微分方程。

Via the stochastic averaging method, the four-dimensional system is reduced to a two-dimensional one. Through the logarithmic polar transformation , and then Girsanov theorem and Feynmann-Kac formula, the backword differential operator is then obtained. By expanding the eigenfunctions as a Fourier cosine series, the approximate analytic expansion of the moment Lyapunov exponent is then obtained.

首先在经典二元机翼颤振方程加入随机激励，通过随机平均法，Girsanov定理和Feynmann-Kac公式得到关于矩Lyapunov指数的特征值问题，其次采用Fourier余弦级数对特征函数进行正交展开得到系统矩Lyapunov指数的近似解析式。

At last, adsorbent and covalent Ag nanoparticles modified electrodes were prepared by adsorbent and covalent method, respectively. The electrochemical behaviours of SCN-, brilliant cresyl blue and nicotinamide adenine dinucleotide on modified electrode were studied by Cyclic voltammetry, differential pulse voltammograms and electrochemical impedance spectroscopy.

最后，用吸附法和共价键合法制备了吸附型和共价自组装银纳米修饰电极，采用循环伏安法、示差脉冲伏安法和交流阻抗谱等电化学方法研究了SCN-、灿烂甲酚蓝和还原型烟酰胺腺嘌呤二核苷酸的电化学行为。

This paper discusses the method of hypothesis testing on equation parameters,and the way of getting new equations to explain the speed, cceleration and jerk through calculating the differential coefficient of cubic equation.

该文还介绍了方程参数显著性检验的方法，并通过对方程进行多次求导，得到新的方程，来描述研究期间土地利用类型面积的变化速度、加速度以及加加速度。

The methods to calculate the differential current of fault phase and sound phase were discussed. The proposed method can eliminate the influence of capacitor current. The sensitivity and security can be realized.

在区外故障或者是区内串补安装点故障情况下，理论上新算法完全不受电容电流的影响，实现了差动保护安全性和灵敏性的统一。

Combining the functional analysis method with the heat conduction differential equations the finite element mathematic modal as the solution to the period cyclic symmetric structure temperature field was constructed.

试验研究了SiCp_A356复合材料在20℃～450℃之间的拉伸力学性能、循环应力应变响应以及应力松弛行为，以经典的弹塑性增量理论作为塑性模型、以经典的Dom幂率方程作为蠕变模型，引入温度效应，建立了适用于制动盘结构分析的热弹塑性-蠕变本构模型。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。